Hydraulic pressure regulator for driving an adjustable hydraulic displacement unit.

[0001] The invention relates to a hydraulic pressure regulator for an adjustable hydraulic displacement unit.

[0002]Ahydraulic pump or a hydraulic motor as a hydraulic displacement unit is understood. These are adjustable, so that the receiving torque and the output torque can be adjusted at a hydraulic pump in a hydraulic motor.

[0003] The receiving torque of a hydraulic pump can the size of the skew angle, which on the position of the power piston is specified, are adjusted. Equally the output torque of a hydraulic motor can be adjusted the size of the oblique angle, which is set on the position of the control piston, . Such adaptation of the receiving - or delivery torque of the can for the generalized Pumpenbzw. the motors operating at a displacement unit in a hydraulic axial piston machine and again be generalized.

[0004]Ahydraulic pump by the swash plate angle the receiving torque is adjusted. This angle is effected by the position of an actuator piston the default. This position is defined, by a certain predetermined oil pressure, the so-called setting pressure acts on the actuating piston by a hydraulic pressure regulator. The restoring force of a compression spring in a direction opposite thereto acts on the actuating piston.

[0005]Acorresponding contraction of the compression spring therefore by the present oil pressure actually can take place, a correspondingly large bearing surface must have the power piston. It is clear, that the hydraulic pressure regulator must be capable, corresponding quantities represent oil, with which the displacement of the control cylinder can be filled or emptied in a acceptable immersion time.

[0006] Is the required position of the power piston in the cylinder reaches the required pressure level equivalent, can the oil connection from the output of the hydraulic controller to approximately are disabled. Building a completely tight system would achieve not, because maintaining the components in a hydraulic system always operated a small leakage requires lubrication, which is in turn for avoiding increased wear necessarily.

[0007] To achieve a revised receiving torque reference value is an increase in the actuating piston stroke required of the hydraulic pump, the output pressure of the regulator must be increased from its output for oil connection of the actuating cylinder and simultaneously a continuous or a correspondingly low flow resistance with a large oil connection oürschnitt released, allowing a correspondingly high oil flow, the movement of the power piston within the immersion time is required.

[0008] To achieve a revised receiving torque set value however a shortening of the piston stroke of the hydraulic pump adjustment necessary, then the output pressure of the regulator must be lowered from its output for oil connection of the actuating cylinder and simultaneously with a continuous large oürschnitt oil connection are released, so that the volume in the cylinder to be filled by the reduction of the amount of hydraulic oil for the excess supply tank can drain.

[0009] In the so-called medium pressure range, the order of a few hundred bar and the insert in a region corresponding to mobile working machines, the drive of a hydraulic pressure regulator requires, the hydraulic oil is provided for acting upon the adjusting piston via whose output, a comparatively high pressure level and a comparatively high oil flow output side input side already. For these reasons such pressure regulator being established generally in two stages. The so-called precursor can then are controlled by an actuator, based on a electromagnet and described as proportional solenoid in the hydraulic bspwbspw. is, . The default on-board network voltage of 24 V and then satisfies therefor at a maximum activation of the proportional magnet a current of 1a, what can be expected of today's as standard control devices. The precursor output pressure is already existing on a sufficiently high pressure level for driving the main stage then. (The for driving the main stage required oil flow, is significantly less than the position piston for driving said.)

[0010] Can of course system failures, such as a defective electronic or electrical connection failure of components in the hydraulic system or leak or whole etc, never be excluded. Safety rather malfunctions, and upon the occurrence of technical errors must be avoided secondary error risks. Ideally even should an error be possible a further operating the mobile working machine case.

[0011] Such a long embodiment for the latter is reacted by a hydraulic motor driven fan is operating a fair needs.

[0012] Only a small heat dissipation is required, in the hydraulic motor is correspondingly less than the need for comparatively high hydraulic power fed in is the case cooling benefits. The relevant hydraulic motor or the fan would be damaged, this cooling function would clearly no longer function corresponding to or restricted, which could damage by overheating as a secondary drawing itself. A defect in the chain of driving the fan would effect a failure of the actuator for driving the hydraulic motor before but before the precursor of the hydraulic e.g. pressure regulator, then this would not lead to a fan failure, when its control is advantageously designed such, that the actuating piston of the fan hydraulic motor adjusts automatically to a stroke position and remains there in this case error, wherein a maximum skew angle is concerned the mechanical maximum power outputs and whereby the hydraulic motor for driving the fan. In a corresponding overheating is avoided.

[0013] The concept is also applicable for positioning of hydraulic pump power piston. On the given example a demand fair return fan operation, of a so-called Fixmotor may, i.e. a hydraulic motor, whose oblique angle is not adjustable, are operated, and the desired variability by the presence of a specially Fixmotor adjustable hydraulic pump associated with this are achieved. Here is the Fixmotor connected to the hydraulic pump via an oil circulation, by means of such a pressure regulator whose actuating piston is positioned, wherein the absence of driver driving the fan to a maximum outward pivoting of the associated hydraulic pump leads, which - with the proviso, that the coupling path on this hydraulic pump, the oil circuit, the Fixmotor up to the fan works - is ensured, leading to a failure of the fan not driving the same that a failure.

[0014] Is in principle the latter approach existing cooling demand in all stationary systems (e.g. in industrial plants or units for power generation etc) operated and operated in all mobile systems and in particular to such systems for vehicles e.g. possible offers, which hydraulic components are already present, such as in mobile working machines. It is also the concept of fan operation previously described embodiment a total of many inserts, in which the position setting of the power piston by a so-called regulator advantageously with falling characteristic (see) takes place.

[0015] Clearly also exist under participation of hydraulic displacement units such functions which operates at the failure driving must avoid mandatory for avoiding damage. Examples of such functions from the scope would be a mobile working machines for the traction drive or for moving of equipment e.g. rotating a superstructure or moving a boom displacement unit used. For such functions is necessarily used a controller used with increasing displacement units each characteristic.

[0016] Driving the precursor of a hydraulic pressure regulator by so-called proportional magnet is widespread. A drive by a different but can also electric or other actuator or a purely mechanical coupling to a control lever take place. A hydraulic pressure regulator may also be a hydraulic pressure regulator with case end with increasing characteristic not only in scope also characteristic mobile working machines limited, but generally for fixed or mobile operated systems in a system controller or a system controller are used. In the use of the controller in a system controller the output value as a function of the actual value takes a certain system operation in response to a size or different sizes clearly defined value. In the use of the controller in a system controller or remains on those whose output size value tends, wherein the controlled variable has reached its set point is reached or.

[0017] Figfig. 1 (slightly idealized) shows current-to-pressure characteristics of a hydraulic pump and a hydraulic unit consisting of a pressure regulator. It is a two-stage hydraulic pressure regulator in both cases, its precursor a of current/electric actuator includes for example a proportional magnet to be driven. The dashed line refers to the characteristic such a registered hydraulic pump controller unit with increasing characteristic. The other, line indicates the characteristic represented by the juxtaposed dash-points a hydraulic pump controller unit with falling characteristic. In the shown diagram over the drive current I is the output pressure P_{IS H} D of the hydraulic pump applied. The maximum drive current I=Imax is such a regulator is typically about 1a. In hydraulic pumps for the so-called medium pressure is the maximum output pressure P scope_{IS H} D is=PhDs, max at about 320 bars.

[0018] The two mapped characteristics are idealized so, that within the entire current range, in which a change of the hydraulic pump output pressure is PhDs, each hydraulic pump output pressure P as a function of a linear_{IS H} D and the drive current is /. In practice such a linear dependency is sought, but not achieved. Existing non-linearity at high tends the primary drive, the power drive supplying hydraulic pumps to speed fluctuations. The linearity is therefore particularly important for such hydraulic pump regulator units, a high proportion of the output power of the prime mover relating.

[0019] Described herein can also be amended to show the operation of hydraulic motors and hydraulic displacement units transmitted generalise, also outside the pressure area such. In the characteristic curve of a motor controller unit 1 figfig. corresponding representations on the abscissa the delivery torque of the hydraulic motor must instead of the pressure P_{IS H} d is the pressure level at the high pressure outlet of the hydraulic pump>, are applied.

[0020] 2 Shows the schematic view of a hydraulic pump 1 and a figfig. the hydraulic pressure regulator 2 existing unit, to the further components of the hydraulic system by the demarcation of which total outer dotted line is represented. This border within the delineated oil connections between those existing switching symbols inside the pressure-tight housing of the hydraulic pump screwed together extend both 1 and 2 of the pressure regulator. The ölanschlüsse this unit are the suction line sec, coming from the storage tank to the hydraulic pump by the promoting oil and their high pressure related to exit a, via which the hydraulic consumer and a return duct for storage tank are supplied, so that at a corresponding actuation of the power piston and the leakage oil can be returned to the drain 1 a is there. The return line itself is not shown in the figfig. 2. The operation of the hydraulic pressure regulator 2 essential compounds for storage tank by the tank symbols are a hydraulic switching picture can be seen.

[0021] Is the precursor 2a is located extending right down sub, whose two hydraulic inputs (leads) on the underside of the control slide switch character are entered. The left this is the hydraulic oil storage tank with the inputs, i.e. connected with the low pressure side. The other hydraulic input via a throttle is connected with the high pressure outlet of the hydraulic pump 1 2c. On the left side of the control slide is a proportional solenoid, against the restoring force of the right side of the slide by its energizing compression spring located therein can be moved. In the imaged state of the slide in that position of end stop, the proportional magnet is energized or deenergized at a correspondingly weak, whereby the force of the compression spring is not overcome by the bias outgoing. This end stop position is present in the hydraulic oil tank presence, i.e. the low pressure level, directly on the on the upper side of the control slide switch symbol mapped hydraulic output terminal of said precursor 2a passed, whereas the pressure level of the high-pressure output of the hydraulic pump from the hydraulic output terminal of said precursor 2a is completely decoupled. In this end stop position of the slide of the precursor is in a stationary state at the output thereof relative oil pressure of 2a 0 bar in front. Before reaching the steady state flows from the range, with respect to the precursor output by a direct oil connection this part of the main stage contained excess hydraulic oil for storage tank 2b standing back towards. This reflux via the precursor 2a. The oil inlet on the then be designated as the outlet port and the precursor output by the tank marked with the symbol of the symbol. With respect to the oil flow from the oil can therefore designated as precursors output terminal from the precursor flow into and flow out 2a. Therefore the name as a signal or control technical abstraction precursor output - to understand.

[0022] An energization of the proportional magnet is a threshold current (magnitudes) exceeded the height of, sets in another (excessive amount) of current I increasing in the direction of a movement of said pusher a compression spring subject to contraction. The current I reaches a certain height I₂ , which magnitudes greater than is H, then reaches the slide in a position in which the pressure level of the remains and hydraulic oil supply tank is completely decoupled from the precursor output, whereas the high pressure outlet of the hydraulic pump 1 via which the precursor 2a 2c the precursor output is supplied upstream throttle, whereby the pressure relative to the pressure level of the high-pressure present there - output of the hydraulic pump - takes its maximum value. Is said current I between the values H and H, then moderate current increase amount causes movement of the slider to the right, which in turn causes an increase in the precursor output pressure level. Is said current I between the values of L-I and L₂ , then according to amount causes a lowering of the current I movement of the slider to the left, which in turn causes a decrease in the precursor output pressure. By a corresponding sequence described in the text and oil volume within the geometric configuration of the oil connections 2a precursor flow resistors in such a dependence on the arising there position of the spool, that within the current range of L and L₂ a linear correlation between the current difference approximately L L I and the precursor output pressure is (see para course of size_{V IS} 3 figfig. s).

[0023] From the diagram it can be seen, that the axial position of the slide of the pressure spring and not solely by the proportional magnet produces forces. On the contrary the slide so that the precursor output pressure impressed, that this additional, in the same direction as the compression spring of the outgoing force acts. To thereby form an automatic control of the precursor output pressure and a damping leading to its maximum value limit. Leads to an unwanted increase in the precursor output bspwbspw. interference pressure, increases the pressure of the restoring force of the compression spring due to said return - by the proportional magnet on the slide support counterforce to outgoing force acting. Bspwbspw. leads to a decrease in unwanted interference precursor output pressure, reduced by the described mechanism the counterforce to the proportional magnet on the slide from existing outgoing force acting. By abrupt load change corresponding disorders appear especially, i.e. transient changes in the power consumption of the hydraulic consumers.

[0024] For the indication given at this point 2a precursor was closing, that each position of the spool that sets, wherein a balance of the following forces is:

the restoring force of the compression spring - depending on the slide position

- the force of the proportional magnet current as a function of the

- the force, the precursor output pressure to a defined mating by recirculating the sets on the slide.

(Wherein a non-occurrence of contraction of the compression spring is the slide on its bearing surface at, hence also a defined position results. from the point of view forces viewing is a bearing force added, whereby a Gleichgeweicht of the four mentioned forces ultimately present.)

[0025] Above the previously considered in the diagram the main stage 2b 2a precursor is entered. The precursor output pressure via a hydraulic control input of the main stage, more precisely its so-called control surface formulated, supplied. The remaining control input of the main stage is directly connected with the high pressure outlet of the hydraulic pump 1 2b. These two control signals meet their respective control surface on, from which two super, on the slide of the main stage 2b acting forces arise, the restoring force of the spring belonging to the main stage 2b adjustable counter. According to the balance of forces f_{IS H} p + f_{V IS} s=f_{f is} a defined axial position of the slide resulting. With F_{IS H} P is that force is indicative, at the high pressure outlet of the hydraulic pump 1 to the pressure level present on the slide exerts its control surface. With F_{V IS} s denotes that force, the present pressure level on its control surface exerts on the slide at the precursor output. F IS_{f is} the restoring force of the compression spring is.

Case 1:

[0026] Is initially due to low pressure level corresponding to the forces sum f is_{IS H} p + f_{V IS} s is low for the time being such, that in the primary stage or a contraction of the compression spring is not hardly 2b there, - with respect to the existing arrangement remains in the diagram - the slide on its right stop position first. In the circuit diagram corresponding to the indicated position of said pusher, wherein a direct connection between the main stage output and the hydraulic oil storage tank is. In this case the counter spring of the hydraulic pump power piston has at its end stop 1a these pressed. In a further to the previous text of this portion have a value of the relative precursor output pressure conformal adoption 0 bars.

The actuating piston is currently considered the likelihood end stop (in the symbolic representation of the adjusting cylinder into a position on the adjusting piston 2 shows figfig. 1a 1a, which mapped to the slide position of the main stage is not consistent 2b there. The slide position of the main stage 2b provides a direct connection of the actuating-cylinder lnnenvolumens for hydraulic oil storage tank. The symbolism of the engine and the hydraulic pump 1 is by inscription to recognize, that the existing situation at maximum skew angle a and thus this maximum stroke of the engine piston operates under. Since the pressure level of the high-pressure output of the hydraulic pump 1 via the corresponding control surface is impressed on the slide, is acted upon by a force exerted, the restoring force of the compression spring which counteracts there. This may be compressed a certain length, sets a movement of the slide a, the oil connection between the high pressure outlet of the hydraulic pump and the main a stage output is prepared. The thereby causing a rising oil pressure in the oil flow from the main insertion end stage output into the interior of the adjusting cylinder 1a existing volume. In such an arrangement wherein the volume pressure prevailing there described setting pressure. An increase of the actuating pressure on the power piston 1 leads swung back A to a swash plate, whereby the pressure level of the high-pressure output of the hydraulic pump 1 decreases. On this principle of feedback while maintaining the respective bias the actuating piston return spring resulting and the compression spring in the main stage at the high pressure outlet of the hydraulic pump 1 a defined pressure level 2b. This is its maximum value time and the constellation, which adjusts, if a relative pressure level present on the precursor output 0 bars. By the adjustability of their bias in the main stage situated on the application of the regulator 2 compression spring 2b may be adjusted maximum value.

Case 2:

[0027] From the successes achieved an increase in the final stationary case scenario described under 1 precursor output pressure. Inserting an increase in forces sum f is_{IS H} p + f_{V IS} in the main stage leads to such a slider 2b sec first movement, through which the flow resistance and the pressure drop from the high pressure outlet of the hydraulic pump along the equally 1 for main stage output reduced existing oil connection, an increase of the actuating pressure with a further contraction associated what therefore leads to the power piston return spring, because on the main stage output the corresponding quantity of oil for filling the volume in the cylinder can flow there are coming. Movement of the power piston but in this arrangement leads lain that direction, wherein an increase in the contraction of the power piston return spring is, the swash plate of the hydraulic pump 1 to a pivoting back and thus pressure decrease at its high pressure output. That in turn leads to a relief of the main stage return spring, so that after a certain setting pressure-raising a stationary equilibrium of forces f is_{IS H} p + f_{V IS} s=f_{f is} in the same slide position sets, wherein a broad main stage output to said high pressure output of the blockade of the hydraulic pump 1 and the tank return is.

Case 3:

[0028] This has just described feedback exists in an analogous manner upon the reduction of the forces sum f is_{IS H} this movement of the slide takes place first Fvs + para -, the hydraulic oil from the power piston velocity on the main stage output for storage tank 1a causes. In servo-pressure lowering the insertion end of the swash plate of the hydraulic pump 1 will give rise to greater pivoting and thus to an increase in oil pressure at its high-pressure output to over time such a reduced setting pressure results, wherein a stationary equilibrium of forces f is_{IS H} p + f_{V IS} s=f_{f is} in the same slide position adjusts, in the broad main stage output to said high pressure output of the blockade of the hydraulic pump 1 and the tank return is present.

[0029] With respect to the oil flow from the main stage output terminal can therefore designated as oil from the main stage flow into and flow out 2b. Therefore the term main stage output as a signal - or regulatory abstraction to understand and not as marking a flow direction.

Case 4:

[0030] At maximum output pressure of the precursor on the slide in the main stage is 2a 2b acting forces sum Fhp + Fvs still correspondingly large, the skew angle a of the hydraulic pump over the already stated mechanism 1 to a low value, although the force F thereby_{IS H} p has a comparatively low value.

[0031] Figfig. 3 shows the current-to-pressure characteristics of the pressure level (slightly idealized) at the high pressure outlet of the hydraulic pump 1 and the hydraulic pump regulator unit such a precursor output pressure with falling characteristic.

[0032]Astatement by the electrically controllable two-stage hydraulic pressure regulator subsequently with increasing characteristic for driving a hydraulic pump on the basis of a switching picture:

[0033] Although the said two different characteristic types of Hesse from the controller and the pump unit using two identical hydraulic pressure regulator and respective different existing total hydraulic pump speech realize. Is the same as part but usefully pump used, as their structure is much more complex than that of a regulator. That is why the two different for Hydrau-type likpumpen regulator units a) with falling (figfig. 2: pressure regulator 2) and b) with increasing current-to-pressure characteristic (figfig. 4:

Pressure regulator 2'), the hydraulic pump 1, 1a situated in the upper frame corresponding symbols and inscriptions (see figfig. 2 and 4) identical switching. It compares the two in the lower frame controller switching images located 2.2 ' (2 and 4 figfig.), one finds such, that these are identical for the two main stages 2b also. The switching images based on the differences between the two controller types limited only the precursor 2a, 2a '.

[0034] Actually would be the construction of pressure regulator 2, 2a ') with falling and b) with increasing pressure - possible - current characteristic, in the structure of its precursor 2a, 2a' same but instead have different main stages and 2b. Such manufacturing techniques have the disadvantage would be speech but consuming and, in the lower pressure range is not that regulation is possible.

In the easiest implementation would it, independently of the type of automatic controller to use identical hydraulic controller and only driving the electric primary actuator to adjust, as needed to achieve thereby a rising or falling characteristic. Independently thereof, whether the regulator is operated with rising or falling characteristic, would with a breakdown of the egg. Primary actuator on the main stage output result the same pressure level. As stated to initially, but in the case of a failure of the egg to for safety reasons. Primary actuator on the main stage output the maximum pressure level are present then, when a controller 2 with falling characteristic is represented. Should present the minimum pressure level however, when a controller 2' with increasing characteristic is represented.

[0035] Wherein the controller increases the output pressure characteristic is the precursor 2a ' such returned on this, that this together with the proportional magnet force on the pilot piston against the restoring force of the compression spring there outgoing acts.

[0036] In the state that the pilot piston 4 figfig. imaged in the end stop positions, the proportional magnet is energized or deenergized at a correspondingly weak, whereby the force of the compression spring extending from it for contraction is not sufficient. This end stop position is the level of the present hydraulic pump high pressure output on the precursor 2a ' upstream throttle 2c the precursor output supplied. With this and the high pressure outlet of the hydraulic pump in the existing pressure level directly on main stage 2b on their respective control surfaces and forming one of the main control piston acted upon by the adjustable compression spring restoring force against outgoing directed forces sum f is_{IS H} p + f_{V IS} these forces leads to a strong contraction of the sum - sec adjustable compression spring, it follows a correspondingly high actuating pressure, its increase in hydraulic pump 1 to a approaches the swash plate leads, whereby the pressure level at the output of the hydraulic pump 1 high pressure reduced. In the presence of a low pressure at the high pressure level is considered arrangement output of the hydraulic pump 1 the forces sum f is_{IS H} p + f_{V IS} sec tends to low, because each of the two forces from a direct or indirect ultimately returning the high pressure outlet of the hydraulic pump 1 is based on the existing pressure levels. Therefore leads the forces sum f is_{IS H} p + f_{V IS} only seconds to a significantly limited contraction of the adjustable compression spring. In turn this means a limitation of the maximum possible control pressure, which in turn decrease a skew angle a is thereby increasing the pressure level at discourage Flochdruckausgang causes the hydraulic pump 1.

With this embodiment the existing principle of self-regulation in this arrangement was also shown.

[0037] At a maximum current of the proportional magnet is a direct oil connection between the hydraulic oil supply tank and the precursor output. Accordingly there makes the oil pressure level to contribute to a contraction of the adjustable compression spring 2b of the main stage. In the primary stage as long as the pressure level of the high-pressure output of the hydraulic pump 2b on its control surface adjacent alone are not sufficient for a contraction of the adjustable compression spring 1 there, is the relative actuating pressure at 0 bars. That means a strong outward pivoting of the hydraulic pump 1, whereby a high pressure level at its high pressure output results. The latter is correspondingly high pressure level, a contraction of the adjustable compression spring located in the main stage 2b cause, a certain pivoting back of the swash plate is carried out. Thus an automatic throttling of the high pressure outlet of the hydraulic pump is at maximum pressure level before.

[0038] The figfig. 5 shows a longitudinal section of a two-stage pressure regulator 2 corresponding axial technology in addition to a hydraulic connection to indicate its occupancy. The output of the pressure regulator 2, the so-called setting pressure bore 3 is a an hydraulic displacement unit 1 with the actuating cylinder 1, here in the example with an operating hydraulic pump connected in 1 type Ouadranten operation. The applied pressure in the cylinder of the hydraulic pump 1 a defined positioning of the corresponding member 1a effected in - in the case of axial piston pump is a swash plate - this is in the direction of its zero position. When the member is in its zero position or the swash plate, wherein rotation of the engine is a very small axial movement of the engine piston, whereby the hydraulic oil support on for their own lubrication required amount is limited. In this situation the hydraulic consumers/mode is, e.g. a hydraulic motor or a lifting cylinder hydraulic active power not supplied. Is located on the high pressure outlet of the hydraulic pump then a pressure level of the order of 20 bar in front. The pressure regulator 2 itself is the so-called high-pressure bore with the high pressure outlet of the hydraulic pump 1 and 4 connected with the tank via the tank by means of the so-called 5th bore these three terminals 2 - as previously described - can the pressure regulator in the case of a pressure increase (I in) the power piston 1a and supplying oil intended there from the high pressure bore 4 via which the setting pressure bore 3 coming in the case of a pressure reduction and vacating (II to) the power piston 1a removing excess oil intended there across the setting pressure bore 3 and the tank bore 5 abstracting rendering.

[0039] Components of the two-stage pressure regulator with its primary actuator 2a are the precursor 6, 7 the actuating device, the primary stage 2b, various oil connections 8a, 8b, 8c - 2 inside the regulator 9 and closure and seal systems also systems 10.

[0040] The precursor 2a consists of a primary actuator 6 and a counterpart, the control slide/control piston, often referred to as pilot - or pilot piston, along a hydraulic controller axis, which in turn (see) to different oil connections exist, to defined positioning. The primary actuator is often performed based on an electromagnet 6 from a proportional magnet. But it might have other electrical or non-electrical actuator also a a to a direct mechanical transfer a manual positioning action. As players are predominantly applied against compression springs.

[0041] Wherein in figfig. 5 illustrated and hereinafter stated main stage 2b is it a corresponding embodiment technology. The main stage 5 comprises a main control piston 11 figfig. 2b according to, the master piston bore 12 through which the closure screw 10 in its opposite actuating device 7 is stamped a biasing force. As mentioned above, the adjusting device 7 is mostly from a compression spring, whose bias is adjustable manually.

Without the diameter along certain portions of its circumferential surface taper would main control piston 11 by the corresponding bores 3, 4, 5, 8a, 8b, 8c in the regulator housing between the outer terminal of the regulator 2 (I in) created oil passages for connecting the hydraulic pump 1 and the precursor 8b with the high pressure outlet and the oil connection between the outer terminal 8c 2a (II to) 5 of the controller 2 for the hydraulic oil supply tank and the precursor 2a each block. With a marked along its surface being the outside diameter of the main control piston 11 such portions to the inner diameter of the master piston bore 12 incorporated in the regulator housing 2d adapted, that the main control piston 11 can move therein over a pronounced oil film, but not regular along these two Flächenangrenzungen oil flow, but only a small leakage occurs. The main control piston 11 has its circumferential surface along said portion T is on a reduced diameter. From the main piston 12 and the bore to thereby form a main control piston 11 confined volume tonnes, a so-called control volume, which is extended along the piston longitudinal direction to an appropriate extent, so that the main control piston 11 installed in a controller housing 2d independently of its position inside the pressure regulator 2 from its outer terminal 5 for the hydraulic oil storage tank oil connection to the corresponding terminal of the precursor remains a 2a. Along the portion of its circumferential surface is H has a reduced diameter on the main control piston 11, whereby a between the main piston bore 12 and the main control piston 11 along the piston longitudinal direction limited control volume is H, is present. The longitudinal side this control volume is H such extended, so that the main control piston 11 installed in a controller housing 2d, independently of its position inside the pressure regulator 2 from its outer terminal 4 for the high-pressure output of the hydraulic pump 1 to the corresponding terminal of the precursor remains a oil connection 2a.

The adjusting device 7 on the opposite surface of the main control piston 11 is based on a stamp these introduced centrally axial bore. Irrespective of the position of the main control piston 11 projects into this bore in the closure screw 13 injected into a needle roller 10. Upon reaching the end position of the main control piston also left side 11 is a remaining portion on the right side of the needle roller 13 its longitudinal bore not filled, because the drilling depth greater than the corresponding length of the needle roller 13 is. Characterized along the longitudinal bore remains always a volume n is obtained, this longitudinal bore and projecting from the end face of the needle roller 13 thereinto is limited. The main control piston 11 also is in a transverse bore 14, which connects the volume n with the volume is H. The needle roller 13 is a pin with a tolerance of a few microns precision as regards their diameter, the left side of the main control piston 11 centrally contained almost leakage free axial longitudinal bore closure represents.

[0042] In the shown axial position of the main control piston 11 is neither with the high-pressure bore 3 setting pressure bore 4 connected with the tank still bore 5. It is therefore the situation described previously, that the oil pressure in the actuating cylinder 1 a of the hydraulic pump 1 has reached those value, wherein the setpoint value at high pressure output is present.

[0043] According to the naming of this portion remains in it - except their hydraulic connections for main stage 2a - the precursor itself outside the viewing.

First performed under the pressure level with the viewing of the oil contained in the main stage 2b standing PhDs loaded surfaces components. The walls of the high-pressure bore 4 are to be considered as rigidly in the housing 2d integrated controller, so that no influence on the axial piston position thereof is exerted. By the presence of the two inner bores and those described in the previous section on the main control piston 11 tapers of the outside diameter, which in its installed state in the regulator housing in the region of the high-pressure bore 2d are 4, exist in the corresponding portion of the main piston bore on the main control piston 12 and 11 with the oil under the pressure level PhDs loaded surfaces such standing. This leads - with respect to the direction of the longitudinal axis of the main control piston to axially and radially - 11 - forces, wherein the latter cancel each other out.

At the left end of the main control piston in the axial bore of the centrally located 11 causes there present

from the high pressure outlet of the hydraulic pump 1 - - the occurrence of a resulting force F derived from oil pressure per_{IS H} para on the main control piston, the latter against the restoring force from the actuator 7 f is outgoing_{f is} presses. In volume n is the oil pressure P is applied_{IS H} D is the righthand end of the internal bore is located and thus the main control piston, which is supported on the compression spring of the actuating device 7. End of this internal bore has a conical shape to be detected is on, what results due to the manufacturing. For the height of the pressurization force caused by the height of the oil pressure and the size of the cross sectional area of the internal bore only considerably. This cross-sectional area of the main control piston is the control surface 11 for the pressure level at the output of the hydraulic pump 1 is high pressure. Diametrically, i.e. on the link side open end 11 of the main control piston is in its internal bore surface of the needle roller 13 projecting into the punch with the oil pressure P is_{IS H} D is acted upon, said on the closure screw 10 as to be considered is fixed rigidly to the controller housing 2d.

[0044] In the region of the closure screw 10 a by these results, the master piston bore 12, the main control piston 11 and the needle roller 13 surrounded volume V, that in turn is connected with the control pressure bore 8a. The latter is that bore, the pressure level of the precursor on the output of the main stage is passed to the corresponding input 2b. Therefore lies in the volume V of the pre-output pressure P permanently_{V IS} seconds before. With respect to the main control piston 11 is this pressure P_{V IS} s through the presence of the needle roller 13 from the (pressure-tight) not concealed part of its die surface, which in this context represents the output pressure of the control surface for precursor 2a, impressed. The force f applied to the main control piston 11 thereby_{V IS} also contained in the actuator compression spring supported on the s 7.

[0045] Is the main control piston 11 of the adjusting device 7 of the pressure regulator 2 (to the left) sufficiently far away, are the adjusting output of the pressure regulator and the internal volume of the adjusting cylinder 3 so that the hydraulic oil storage tank 1a connected. As long as the main control piston 11 remains in such a position in the hydraulic oil storage tank flows from the actuating cylinder 1a hydraulic oil from, with a corresponding movement of the power piston of the adjusting what clearly associated cylinder 1a, to the actuating piston (i.e. the left side) its corresponding stop position has reached.

The main control piston 11 presses against the actuator 7 (to the right) appropriate weight of the pressure regulator 2, compressing the compression spring located therein sufficiently, the control output of the pressure regulator 2 and 3 are the internal volume of the actuating cylinder with the high pressure outlet of the hydraulic pump 1 1a connected. As long as the main control piston 11 flows from the high pressure outlet of the hydraulic oil remains in such a position in its cylinder 1 a is coming into hydraulic pump 1, with a corresponding movement of the power piston what clearly associated, corresponding to the power piston (i.e. the right side) its has reached a position stop.

There is a central position of the main control piston 11, in which the control output 3 of the pressure regulator 2 with the high pressure outlet of the hydraulic pump 1 nor with the neither hydraulic oil storage tank is connected. Apart from a leakage path for maintaining said oil lubrication is required then the control piston of the hydraulic pump 1 on both sides necessary from the hydraulic oil main circuit separated. As a result of the rams 1 a is its axial position holds, since the hydraulic oil (almost) is incompressible and the surrounding walls are rigidly considered oil volume.

The compression spring in the actuating device 7 is (approximately) proportional to return action exerted by the contained by the displacement of the main control piston 11 induced contraction length. This restoring force acts against the sum of the two forces, the pressure level of the high-pressure output of the hydraulic pump by the abutment of the 1 and the precursor output pressure of the precursor on the main control piston 11 shown on their respective control surfaces 2a. Such a contraction length of these three forces is a Gleichgeweicht in the actuator compression spring contained before 7, in which the main control piston 11 in this position as designated position, then operates with the proviso, that the mechanical side of the hydraulic pump 1 present on the speed torque trajectory is constant, the hydraulic pump regulator unit 2 in a stationary operating point.

Operation of the hydraulic pump regulator unit when there is in a stationary operating point 2 by a corresponding activation of the electric actuator 6 the primary precursor output pressure increases, moves the main control piston (to the right) for actuating device 7 of the pressure regulator 11 towards 2, compressing the coil spring therein to an appropriate extent, so that the adjusting output 3 of the pressure regulator 2 and thus the internal volume of the adjusting cylinder of the hydraulic pump 1 are connected with the high pressure outlet 1a. As long as the main control piston remains in such a position, hydraulic oil flows from the high pressure outlet of the hydraulic pump 1 in their coming into cylinder 1a, with a corresponding movement of the power piston is accompanied by what clearly, the swash plate of the hydraulic pump 1 triggers a swung back. This in turn leads to a decrease in the pressure level at the high pressure outlet of the hydraulic pump is reduced as a result of the resetting unit 7 at the 1st main control force opposing piston 11, so that the main control piston 11 reaches its center position again and then the oil pressure in the actuating cylinder 1a remains elevated.

Operation of the hydraulic pump regulator unit when there is in a stationary operating point 2 by a corresponding activation of the electric actuator 6 the primary precursor output pressure reduced, acting on the main control piston 11 decreases, the contraction of the coil spring contained in the setting device 7 of the pressure regulator 2 leader. The main control piston 11 moves consequent to the left, so that the adjusting output 3 of the pressure regulator 2 and thus the internal volume of the adjusting cylinder with the hydraulic oil storage tank 1a are connected. As long as the main control piston 11 remains in such a position, hydraulic oil flows from the cylinder into the hydraulic oil storage tank 1 a is coming into, with a corresponding movement of the power piston what clearly associated, pivoting of the swash plate of the hydraulic pump 1 triggers a stronger. This in turn leads to a pressure level of increase at the high pressure outlet of the hydraulic pump as a result of the resetting unit increases the 1st on the main control piston force opposing 11, so that the main control piston 11 reaches its center position again and then the reduced oil pressure is maintained in the cylinder 1a.

[0046] On the main control piston by the support surfaces respectively the control surface for the precursor output pressure corresponding to large area than the output of the hydraulic pump 1 are designed for the high-pressure can simply be achieved, according to the need that the required forces balances with a correspondingly high influence of precursor output pressure result.

[0047] It is clear from the considerations discussed, that

the high pressure output of the hydraulic pump 1 - 2 and a minimum pressure level determined by the controller a maximum exist.

between these two pressure levels - a linear operating range of the pressure regulator 2 is approximately.

7 - on the actuator displacement this operating range is possible.

[0048] As from the preceding description of the circuit diagrams of a pressure regulator and a corresponding embodiment of a regulator stage technology can be seen, the described pressure regulator 2 is applied the principle of a cascading. This can with a comparatively very low force level of the electrically driven actuator for actuating the main control piston 11 primary 6 of comparatively high control pressure required are applied. The movement of the power piston of the hydraulic pump 1 comparatively high oil volume for streams are from the main stage 2b, the substantially greater than that of the precursor 2a are, managed.

[0049] Described in the aforesaid pressure regulators 2, 2' is the disadvantage, that this characteristic must be constructed differently for realizing a rising or falling. Constructive differences arise in the design of the pilot piston of the precursor, but also in the design of the controller housing.

[0050] The task of the present invention consists, whereas a genus to develop further pressure regulator, which is not only cheaper but also can be simplified manufacturing. Here is a desirable efficient strategy mögliehst identical parts, i.e. as many as possible, ideally all components of the regulator can be of different types (falling/rising characteristic) controller for mounting use.

[0051]Ahydraulic pressure regulator according to this task is achieved by the features of claim 1st advantageous configurations of the pressure regulator to the main claim are the subject of the subsequent dependent claims.

[0052] From a correct hydraulic pressure regulator for driving an adjustable hydraulic displacement unit genus is the precursor of the modified hydraulic pressure regulator, the pressure regulator to thereby define the characteristic curve course. Driving the mechanical or electrical actuator can be primary precursor preferably by means, the desired change of the conveying volume of the hydraulic displacement unit to achieve.

[0053] Therefor comprises the precursor two terminals, their fluid connection by means of a pilot piston of the precursor is controllable proportionally.

[0054] The core of the invention is, that the pilot piston is surrounded by a stepped bushing. The interplay of stepped bushing defines at least one control surface of the pilot piston and pilot piston. The from the pilot piston and the stepped bushing component combination formed in at least two differing mounting positions or differing installation can orientations are introduced into the controller housing. By the chosen from the pilot piston and the stepped bushing installed position within the regulator housing formed component combination is determined, whether a rising or a falling characteristic line selectively alternatively comprises the pressure regulator. Further components, such as return means and primary actuator can not only be constant for both controller types, but also identically into the controller housing are used. The same goes for the implementation of the controller housing preferably also including the corresponding connecting bores between the pre - and the main stage. Of course the main stage is also constant for both controller types.

[0055] Ideally all components of the pressure regulator according to the invention are independent of the mode of operation with positive or negative characteristic identical. This simplifies not only the production cost in the production but may or reduces the also allows a simple conversion controller optionally subsequent times.

[0056] The addition also simplifies the production of the regulator the stepped bushing, in particular of the regulator housing, since the stepped bushing as a separate component with the tolerances allowed easier by folding, while the internal bore of the regulator housing for accommodating in the regulator difficult to reach the stepped bushing can be made comparatively high by comparison under measure. It must merely be ensured, that the stepped bushing is fixed at the intended location.

[0057] According to a preferred embodiment of the invention comprises the stepped bushing, i.e. their internal bore longitudinally, at least two stages, with respect to its inner diameter the distinction. Here is it necessary, that the transition between the stages, i.e. the step between the different internal diameters, the stepped bushing is arranged centrally in the axial direction. This ensures, regardless of the type of mounting that step or the shoulder within the regulator housing with respect to the regulator housing is always at the same position.

[0058] Alternative is possible, the stepped bushing having at least three stages execute, their middle stage the largest inner diameter. It is not necessary, that each stage a constant diameter over its entire length.

[0059] Further comprises the at least one radial groove on its outside surface stepped bushing, via at least one radial bore with an internal volume of this stepped bushing is connected. The radial bore opens in the heel area at a two-stage bushing or sleeve in the region of the middle stage of a three-stage. Even with this radial groove it makes sense, these centrally on the longitudinal axis of the stepped bushing to be arranged, so that the same position regardless of their installation orientation within the regulator housing is. In particular in the region of a first pressure port of the radial groove is provided this precursor. The inflowing fluid to the radial groove and the radial bore is the internal volume of the stepped bushing.

[0060] It is also considered appropriate, the pilot piston when the step socket adjacent the longitudinal bore for continuous longitudinal bore has at least one further Beherbung, subsequently also designated as the longitudinal drain bore. At least two longitudinal bores are preferably provided drain. The longitudinal bores extend continuously from an end face opposite end face of the stepped bushing. The overall development of the stepped bushing may, apart from the at least one radial bore and the at least one longitudinal drain bore be rotationally symmetrical.

[0061] At their end faces comprising the steps preferably bushing recesses, in particular circular depressions, wherein their radii and/or depth mass can be variable. The recesses and/or radii are ideally identical on both ends. At least one of the longitudinal bores is a fluidic connection between the two recesses of the drain end faces is, i.e. the openings of the drain holes of within the recesses.

[0062] The pilot piston of the hydraulic pressure regulator comprises the precursor used preferably at least three longitudinally arranged one behind sections of different outer diameter. It should be noted here, that a constant outside diameter over its entire longitudinal dimension the individual sections not necessarily must have. Wherein the considered portions of the pilot piston it is preferably the sections of the piston, the operatively connected with the stepped bushing, i.e. depending on the position within the stepped bushing can lie. Preferably all three portions are independent of the selected installation orientation at least partially within the stepped bushing, wherein preferably the middle section has the smallest outer diameter. This central portion is thus an internal volume by the corresponding inner wall of the stepped bushing and the middle portion of the pilot piston formed, between the radial bore and a radial groove in the stepped bushing on the existing fluid connection to said first pressure port is the precursor. The outer peripheries of the outer longitudinal sections of the pilot piston are preferably selected in such a way, so that the inner diameter of the outer sleeve or the steps of the step at these stages at a two-stage bushing adjusting. These sections can be cylindrical in shape, but be provided optionally with one or more contours. Between the outer portions of the pilot piston and the resulting thereby respectively opposite inner wall of the stages a gap dimension, the leakage to the usual hardly allows fluid flow.

[0063] By the stepped transition of the central section to the respective external portions each a control surface of the pilot piston is formed, on the fluid located in the interior volume can act. The control surfaces differ from each other with regard to area accessible from the internal volume, in particular by the choice of different outer radii of the outer portions, at least in the following region directly to the central portion.

[0064] At least one opening provided in the outer circumference of the pilot piston can be notch, extending from the central portion at an outer portion of said pilot piston toward its end face extends. Through this opening notch is an appropriate position of the pilot piston a fluid flow from the internal volume into the respective recess of the stepped bushing possible, into which the corresponding piston position wherein opening notch opens. The arrangement of a plurality of notches in an outer portion of the opening is conceivable piston, preferably distributed over the jacket circumference, particularly preferably two or four 90° offset opening notches 180 deg to are provided. The geometric configuration of the opening notch is arbitrary, as prove appropriate forms a rectilinear shape, a convex shape, a concave shape or a mixture of the aforementioned courses of arbitrarily or generalized curved and straight forms.

[0065] The outer portion of the pilot piston does not notch opening having one or more split ring seals before the other hand, the fluid flow in the opposite direction from the internal volume to a minimum (leakage) reducing opening notch.

[0066] It is also considered appropriate, that the pilot piston at its from the at least one mounting location for mounting each stepped bushing projecting ends of at least one stop comprises. This can stop at a stop of the stepped bushing, whose end face bspwbspw., striking, the axial movement of the pilot piston caused by a return means the precursor to limit. Here it is useful, in that on both projecting ends a respective mounting location on the each of the pilot piston is provided efficient length position, depending on the installation orientation to provide the required mounting location with a suitable stop. For example suitable as mounting location a radial groove, serving as a stop ring is insertable into the ideally. In this embodiment the two radial grooves are advantageously carried out those lengths positions, so that the depending on its orientation at the end of the securing ring installation present exactly the longitudinal position of the pilot piston stepped bushing abuts with the end position wherein the opening width of the opening notch on the accompanying Pilotkolebn is present. By this embodiment the hydraulic controller can independently thereof, whether this be performed with falling or rising characteristic as regulator, without having to resort to different components are provided with stops. In an especially advantageous construction because the two radial grooves have the same diameter, so that identical circlips can be used. Alternatively can also be configured with suitable beads of the pilot piston, the adequately serve as a stop at the end of the stepped bushing.

[0067] The return means may comprise for example a compression spring or alternatively a spring plate precursor, their or its bias is adjustable by means of a screw adjusting device ideally. The return means an axially acting force against the pilot piston brings on.

[0068] The mounting the stepped bushing is ideally suitable clamping means for fixing and by clearance fit within the regulator housing. This allows not only simple assembly, but also allows subsequent modification of installation position of the stepped bushing. The mounting is possible but the stepped bushing press fit, but what difficult retrofit conversion. It is also possible by means of screwing in the fixation into the controller housing.

[0069] The invention relates to an alternative embodiment of the controller in addition to the presented invention also hydraulic pressure regulator. This integration is not a separate stepped bushing, wherein their function by the constructional configuration of the internal bore of the regulator housing instead is formed. In this case the pilot piston immediately within the internal bore of the controller housing lie. Here too can be at least a majority of the controller components for creating different (increasing/decreasing) characteristics used, but different for different types of regulator housing members may be necessary.

[0070] With respect to the previously described features can be equally for the controller housing stepped bushing reading. The stepped shape of the stepped bushing can in particular with a corresponding adaptation of internal bore of the regulator housing be formed. Only the outer radial groove the stepped bushing is not necessarily at the corresponding implementation of the controller housing.

[0071] The following advantageous constructions for the pre - and main stage interconnection relate to both variants with and without regulator in the regulator housing stepped bushing.

[0072] The first pressure port of the precursor is preferably via a throttle with the high pressure input of the main stage connected via mating housing bores. An external terminal of the regulator on this compound can output a displacement unit be connectable with a high pressure. Further is the pressure immediately above a housing bore with a control input terminal of the precursor of the main stage.

[0073] The second pressure port of the precursor can also directly or indirectly on the main stage with a low pressure connection of the controller housing be connected.

[0074] The present invention concerns also a method in addition to the hydraulic pressure regulator of a pressure regulator according to the present invention for mounting the precursor or an advantageous embodiment of the invention. Invention boasts method of, first that the pilot piston into the stepped bushing and the combination is used together in the controller housing is mounted pilot piston and stepped bushing. Prior to insertion of the pilot piston into the stepped bushing or before inserting the combination of both components in the controller housing is ideally required the pilot piston nor the stop this applied.

[0075] Before inserting the stepped bushing preferably a mounting of the restoring means for generating the restoring force in the regulator housing, during attachment of the primary actuator after insertion of stepped bushing is required.

[0076] Additional advantages and characteristics of the invention are hereinafter explained in more detail with reference to an embodiment example shown in Figures be. It show:

Figure 1.:

Figure 2.:

Figure 3.:

Figure 4.:

Figure 5.:

Figure 6.:

Figure 7.:

Figure 8.:

Fig.9,

Fig.10:

Fig.11:

Fig.12:

Fig.13:

Fig.14:

a two-stage pressure regulator of a conventional current-to-pressure characteristic idealized,

a circuit diagram of a conventional pressure regulator with falling characteristic,

a linear relationship between the current difference characteristic for clarifying the L L I and the precursor output pressure at a pressure regulator example falling characteristic,

a circuit diagram of a conventional pressure regulator with increasing characteristic,

a longitudinal section through the housing of a conventional pressure regulator with falling characteristic,

a longitudinal section through the precursor of the invention pressure regulator with falling characteristic,

a longitudinal section through the precursor of the invention with increasing pressure regulator characteristic,

a close-up view of the precursor according to figfig. 7,

9b: a detail receiving the precursor according to the figfig. 7, 8 with a cross-section along the axis e s, detailed representations of the pilot piston according to what the figfig. 6 to 9,

a representation of the pressure regulator 6 figfig. according to characteristics,

a representation of the pressure regulator according to characteristics figfig. 7 to 9,

a close-up view of the precursor of the pressure regulator according to an alternative embodiment without stepped bushing and

a close-up view of the precursor of the pressure regulator according to a further alternative embodiment.

[0077] On the basis of the figfig. 1 to 5 have already been detailed explanations for technical base made in the introductory part. On these Figures should therefore not be made again at this point. The core idea of the present invention mainly concerns the constructive embodiment of the precursor or their connection to the main stage in the common controller housing.

[0078] The various details of the invention and modifications thereof are represented in the following advantageous constructions or regulator should.

[0079] 6 Shows the axial longitudinal section of the two-stage invention figfig. pressure regulator in the vicinity of the pilot piston 20 with falling characteristic 21 such a precursor 20a, the component of the invention is. The other hydraulic components of the pressure regulator 20, in particular the main stage 20b, with their switching characters are represented.

[0080] The precursor has only two hydraulic connections 20a 22, 23 on. On the right side of the pilot piston 21 the compression spring 24 located on the spring plate to the left from this exercise on a directed force. The proportional solenoid 26 is shown left of the cut (not shown in the figfig. 6). In the case of energizing of its plunger 27 is a rightwardly directed force on the pilot piston 21.

At this point was anticipated, that the precursor on the throttle and thus reduced pressure level of the supplied 20a 20c high pressure output of the hydraulic pump on the pilot piston 21 exerts a force directed to the right.

[0081] This link is subsequently under examination of existing oil flow within the precursor compounds in detail explained 20a. Are the two opposing forces of the compression spring 24 too low, causing a contraction of the compression spring 24, the stop 28 of the pilot piston 21 is based, which by a circlip mounted on its peripheral surface 28, its preset position is fixed by a groove 29a, on the left side surface of the cover member 30 as a stepped bushing that is the case designated off., is the pilot piston 21 except for maintaining the required components in a - such a lubrication oil existing

- sealing position. As a result almost no pressure drop over the throttle 20c resulting viewed. In the main stage 20b both control inputs are characterized b is, the pressure level of the high-pressure output of the hydraulic pump c with PhDs acted upon.

[0082] In the precursor are the two opposing forces corresponding to high compression spring 20a 24, causing a strong contraction of the compression spring 24, the pilot piston 21 takes a position, a flow of oil in the tank bore 23 by the precursor 20a is possible. Here is, the further the pilot piston 21 is pressed to the right, the flow resistance along the passage channel of the precursor is less the 20a. This means, the further the pilot piston 21 is pressed to the right, is the proportion of the higher pressure levels, starting from the high pressure outlet of the hydraulic pump pressure levels which existing 20c along the throttle falls. This means, the further the pilot piston 21 is pressed to the right, is a constant pressure level at the high pressure output more further - the hydraulic pump - the main control piston of the main stage 20b pressed to the right.

[0083] The axial longitudinal section of the two-stage pressure regulator 20 figfig. 7 shows increases in the vicinity of the pilot piston 21 20a precursor on such a characteristic, the component of the invention is. Here only the mounting orientation of the stepped bushing 30 and the pilot was piston 21 opposite the figfig. 6 amended. In particular were 180° about an axis extending to both components extends perpendicular to the plane rotated in the controller housing is used. An enlarged view of the precursor 20a shows figfig. 8, a detail view of the precursor with a sectional view along the cutting axis 20a-E 9th figfig. shows the non-mentioned to the immediately above-described pressure regulator 20 with falling apply equally characteristic.

On the right side of the pilot piston 21 the compression spring 24 located on the spring plate 25 a force directed to the left on this exercise from. The proportional solenoid 26 is shown left of the cut. In the case of energizing of its plunger 27 is a rightwardly directed force on the pilot piston 21. At this point was anticipated, that the precursor on the throttle and thus reduced pressure level of the high-pressure output supplied 20c on the pilot piston of the hydraulic pump 21 exerts a force directed to the left. This link is subsequently under examination of the existing oil flow within the precursor compounds in detail explained 20a.

[0084] By the proportional magnet 26 on the pilot piston 21 is outgoing force too low on it, causing a contraction of the compression spring 24, the stop 28 of the pilot piston 21 is based on the stepped bushing 30 in this case is the pilot piston 21 into off. that position, wherein along the passage channel of the lowest possible flow resistance and therefore the proportion of the precursor 20a present pressure level, starting from the high pressure outlet of the hydraulic pump pressure levels which existing 20c along the throttle falls, has reached its maximum value. Then has the main control piston of the main stage while maintaining the pressure level at the high pressure outlet of the 20b this hydraulic pump the right side end position reached.

By the proportional magnet 26 is outgoing force corresponding to high, the sum of the two forces against opposing forces (these are the restoring force of the compression spring 24 and by the pressurization of the pilot control piston 21 by the on the throttle 20c supplied and thus reduced pressure level of the high-pressure output of the hydraulic pump) to shift the pilot piston 21 to the right, is an increase in flow resistance along the passage channel of the precursor 20a.

[0085] Should subsequently be described details of the stepped bushing 30. These statements apply to the precursor de controller 20a of both types.

[0086] The pilot piston 21 has no direct contact with the regulator for receiving the axle bore 40 of the regulator housing on existing precursor 20a 20d. The outer surface of the pilot piston 21 is located in a so-called instead stepped bushing 30, which axle bore 40 in the regulator housing 20d within a controller in a precisely defined mounting position is mounted (see figfig. 7 for the de regulator with increasing characteristic and see figfig. 6 for the de-regulator with a falling characteristic curve). The high pressure bore 22 extends in the regulator housing 20d up to this controller axle bore. At this (from the high-pressure bore and the controller axle bore 22 formed) has a radial groove 31 on the beech stages shock location. In the region of this radial groove 31 there is at least one of continuous radial bore for inner volume V of the stepped bushing 30 outgoing, whereby in the regulator from the high pressure port 30 a stepped bushing inserted at oil connection 22 of the controller 20 into the inner volume V of the stepped bushing 30 is. The axial installation position of the precursor 20a, starting with proportional magnet 26 mounted on the regulator housing 20d, the stepped bushing 30 with the inserted pilot piston 21 and its - parts from the spring plate 23, compression spring 24, seal and adjusting screw 41 and the entry angle of the high-pressure bore - existing resetting unit 22 into the controller housing 20d adapted together to, to create the necessary oil connection required that the radial groove 31 in the stepped bushing 30 in a central position. Thus the stepped bushing 30 with respect to their vertical can, in two different orientations in the regulator housing are mounted in both orientations of the stepped bushing 30 and 20d installation remains the previously described oil connection from the high pressure bore 22 for volume V are. The stepped bushing 30 are longitudinally on the two in the figfig. 9a, 9b oürschnitten represented two so-called ölabflussbohrungen 33 visible. At least one such ölabflussbohrung 33 is needed, the number of such ölabflussbohrung 33 can also be higher than two. Apart from the at least one of the at least one radial bore and the opening edge 33 and ölabflussbohrung 44 can be embodied as a stepped bushing 30 rotationally symmetrical component.

[0087] Figfig. into 8 is apparent, that the stepped bushing 30 on both punch faces each centrally arranged circular depressions 34a, 34b are. Both recesses 34a, 34b have the same diameter and the same depth. It is the diameter greater than the radial distance between the two ölabflussbohrungen these recesses 33. To ensure characterized in, that between the two punch faces mounted in the controller housing is a stepped bushing 30 oil connection. As in recognizable figfig. 8, has the stepped bushing 30 from the radial groove 31 - apart from the detected range - a constant external diameter over its entire length, whereas the axially through the stepped bushing bore passing through three sections 35a, 35b, 35c respectively having different diameters. This is in the central region before 35b the largest interior diameter. The respective transition of two different internal diameters is stepped, by what title reflected stepped bushing. The length portions 35a, 35c along the socket axis stages, on the two from each other slightly different, but smaller than in the central region extend this internal diameter, have the same length. The diameter differences of these two lengths 35a, 35c are relatively small and is difficult to distinguish by a Augenscheinnahme. One of the two stages socket ends is therefore advantageously provided with a marking. Because of the above-described configuration of the female outer boundaries stages shows, that this in terms of a central radially cut apart from said marking - - are symmetrical. Characterized in two different orientations in the regulator housing 30 can the stepped bushing 20d are mounted. This orientation is crucial for the type of automatic controller. Precisely for this reason is the mounting of said marking assembly error to avoid very useful.

[0088] Should the pilot piston 21 with its details are described subsequently. The statements apply to both de controller types.

[0089] 10A shows a three-dimensional view of the pilot piston 21 figfig., a longitudinal section through the pilot piston 31 10b figfig.. The proximity of the pilot piston 21 inserted in the stepped bushing 30 in the form of its central axial cut through the de regulator is to see bspwbspw. figfig. into 8. In the recognizable as bspwbspw. figfig. 8, 21 over its length has the pilot piston, via which the pilot piston 21 based on the an axial actuating range inside the internal bore of the stepped bushing 30 is over or may be located, are indistinguishable from three sections 42a, 42b, 42c on. Apart from said Radialnuten29a as reinforcements, 29b, the split ring seals 43 and 44 of the pilot piston 21 facing the opening notch in each of these portions 42a, 42b, 42c on a constant diameter. In the transition region from the outer diameter of the pilot piston within the border of each portion are different portions of different size. The outer diameter of the pilot piston 21 in the central portion 42b is smaller than that of the internal bore of the stepped bushing 30 35b in the section. Thereby to the confined volume V to the controller housing located in a high-pressure bore 20d oil connection 22, taking into account the previous section as from, the description of the stepped bushing 30 given information is clear. In this volume V corresponds to the existing oil pressure on the throttle 20c and thus reduced the high pressure outlet of the hydraulic pump fed at this pressure level (see bspwbspw. figfig. 7).

In the other two longitudinal sections 42a, 42c, in which the pilot piston 21 over its axial actuating range across the internal bore of the stepped bushing 30 or are in contact can, the outside diameter of the pilot piston 21 are in sections 42a, 42c and the inner diameter of the stepped bushing 30 in the portions 35a, 35c exactly matched, i.e. where the stepped bushing 30 having the smaller inner diameter as in their length 35c - 7 - 9 on the side facing the compression spring 24 - has figfig. pilot piston 21 a correspondingly smaller outer diameter. This area of the pilot piston begins at the central portion 42b 42c for existing stage to a length immediately behind the last split ring seal 43, here the fourth split ring seal. The latter is still snugly against the inside wall of stepped bushing 30, when the pilot piston 21, as in figfig. 8 shown, has reached its end position almost, wherein the compression spring 24 provided in the system undergoes its maximum contraction. With the smaller cross-sections along the length 35c between the pilot piston 21 is the gap dimension and the stepped bushing 30 accordingly so matched, the pilot piston 21 that independently of the axial adjusting position only a small leakage to maintain the ölschmierfilms is given. In the arrangement shown in the precursor by the installation orientation 20a figfig. 8 the stepped bushing 30 and the pilot piston 21, the leakage from the high pressure bore 22 located on the right side on the gap between the portion and the portion of the pilot piston 21 42c 35c the internal bore of the stepped bushing 30 substantially avoiding tank bore 23. This split ring seals on the pilot piston as supporting the four radial grooves 43 at present. By the compression spring 24 from the righthand for arranged for adjusting screw 41 associated seal, 8 is not shown in figfig., the escape of hydraulic oil at that end of said regulator housing 20d is prevented. Such leakage path between the pilot piston 21 and on the previously considered the internal bore of the stepped bushing 30, i.e. on the split ring 43 seals across the pilot piston 21 reaches the right end oil through creep region, of the stepped bushing 30 protrudes therefrom, from where a spring plate 25 and on the compression spring 24 past oil connection on the tank 23 is to bore.

[0090] The two ends of the pilot piston 21 are shaped correspondingly, a tilting between the latter and the spring plate 25 and the righthand side of the tappet rod 27 arranged left arranged to prevent proportional magnet 26.

On the aforementioned split ring seals 43 on the piston 21 are two further radial grooves 29a, 29b mounted. Depending on the pilot piston 21 (configuration of the controller 20) is installed position on one of the two radial grooves 29a, 29b secured a circlip 28. In the into the securing ring 28 on the right 8 figfig. mapped configuration outside the radial groove 29b of the pilot piston 21 located stepped bushing 30 placed. Thus the pilot piston 21 for both controller types (rising or falling characteristic) is equal to a part, must each of its both sides in such a distance corresponding to the piston end radial groove 29a, 29b have, since the stop 28 on the opposite side of the pilot piston 26 always proportional magnet 21 needs to be at. Hence the securing ring 28 remains equal to a part, the outer diameter of both grooves 29a must, of equal size 29b be. The groove depth on the side of the pilot piston 21 must therefore with the (slightly) larger diameter be greater.

In the axial position of the pilot piston 21 is represented in the figfig. 8 this due to the energization of the proportional magnet and the pilot piston 26 at this present comparatively far to the right against the restoring force of the compression spring 21 oil-presses 24 pressed. As a result thereof the opening notches 44 on the pilot piston 21 (substantially) closed. A creative possibility an opening notch 44 with rectilinear edges 10a figfig. is to see.

The proportional solenoid 26 is not energized and the absence of the pilot piston 21 at high oil-presses, is this - as regards the orientation of the compression spring 24 - 8 given figfig. pushed that far to the left, that the securing ring 28 on the cover surface (at the end of its recess and) the stepped bushing 30 rests. From the high pressure bore 22 is then, via the radial groove 31 and the radial bore the stepped bushing 30 on the volume V, by the internal bore by the stepped bushing 30 and the taper 35b external diameter of the pilot piston 21 and its opening 42b notch 44 is given, a connection to the adjacent recesses of the controller 30 and the stepped bushing 34a together housing 20d. From there the hydraulic oil on the right side recess 33 can ölabflussbohrungen for the stepped bushing 30 reach 34b, which in turn with the bore in the regulator housing 20d, in which the adjusting screw 41 and the compression spring 24 are supported by it. The latter bore for an impact location of the tank bore 23.

Along this oil path from the high pressure tank to bore 22 described bore 23 by the hydraulic oil is flowing to the pilot piston 44 through the opening notch portion by the determining flow resistance is considerably oürschnittsverengung 21. In order to enable this oil path along the flow resistance and thus also the precursor output pressure for loading the main stage as a function of the axially position of the pilot piston 21 20b defined are influenced.

The presence of oil pressure (this is the precursor 20a on the throttle 20c supplied and thus reduced pressure level of the high-pressure output of the hydraulic pump) into that volume, by the internal bore of the stepped bushing 30 and by the taper of the outside diameter of the pilot piston 21 and its opening 42b notch 44 is given, the hydraulic oil pressure level leads to mutually canceling radial forces and this standing to axial forces. The controller housing fixedly anchored in the stepped bushing 30 axial forces acting 20d do not have function-determining impact. But the axial forces acting on the pilot piston 21 bioterrorism result: tone: #8 - configuration as found at a emergency figfig. present a resultant force, which has the same direction as the restoring force of the compression spring 24. The direction of the resultant force on the basis of current is caused by the oil pressure, because the left side bearing surface 45a (see figfig. 10) on the pilot piston 21 is greater than the right side bearing surface 45b.

[0091] In the configuration of the precursor figfig. 20a according to 6, wherein the stepped bushing 30 and accordingly the pilot piston 21 in the other installation orientation in the controller housing is mounted with respect to the orthogonal to the longitudinal axis and 20d located 180° plane are rotated, the controller 20 has a falling characteristic line. Here via the throttle 20c and thus reduced pressure level of the exercise supplied high pressure output of the hydraulic pump on the pilot piston 21 and a rightwardly directed force from, because the right side bearing surface is greater than the left side bearing surface 45a 45b. In this configuration the hydraulic oil flows at a by appropriate activation of notch 44 on that side of the pilot piston 21 already open opening from, at which the tank 23 is bore. In this configuration the ölabflussbohrungen 33 at the stepped bushing have therefore 30 and its recess 34b on the side facing the purpose 26 proportional magnet, the gap between the internal bore of the stepped bushing 30 and along the corresponding cylindrical surface of the pilot piston 21 embrace the split ring seals in the direction of the proportional magnet 43 26 moving tank leaked due. A certain leakage is to maintain the necessary lubrication. The pilot piston 21 would be from the lefthand existing volume, the leakage oil flow is achieved by just stated, not for the oil recirculation capability into the tank, with respect to atmospheric pressure - - this leaked would form pressure in the volume and the pressure at the accumulating there there outgoing end face of the pilot piston 21 and therefore concerned within a very short time to a defect concern 20a lead precursor.

[0092] 6 And 8 by the longitudinal cuts in the figfig. representations of the pilot piston 21 and thus the components such a mapped in reality invention differ only built up regulator, shown in figfig. 8 that in a de controller with increasing characteristic is used in figfig. 6 and shown in a DE regulator with falling characteristic is used.

[0093] For both configurations according to figfig. 6, 8 exist possibilities of influencing magnetic current-to-pressure characteristic about the hydraulic precursor 20, while maintaining the proportional magnet 26 and the main stage i.e. 20b. Wherein energization of the proportional magnet 26 remains below a first threshold value the pressure level at the high pressure outlet of the hydraulic pump of this electrical current operated unchanged. The threshold current is dependent on the biasing force of the actuator 24 this, and thus dependent on the deformation length and the hardness of the 25 contained in the coil spring 24 and the path length of about which the pilot piston 21 must be shifted, to the opening width of the opening notch 44 changes.

A strong enough proportional magnet 26 provided the pressure level at the high pressure outlet of the hydraulic pump remains unchanged from a further increase the electrical current operated, because achieving this second threshold from the opening width of the opening notch 44 not more changes (e.g. a de-regulator with falling characteristic is fully closed the opening edge) or yet not affect the precursor output pressure level has this amendment.

Depending on the type of automatic controller leads an increase of magnetic flux of the electric current to a between these two thresholds (approximately) linear increase or reduction of the pressure level at the high pressure outlet of the hydraulic pump. (Positive or negative) of the pitch characteristic is dependent on the spring hardness of the coil spring 24 and the size of the precursor contained in the 20a control surface on the pilot piston 21 and the reduction of the pressure level of the hydraulic pump with the output from the high pressure applied to the pilot piston control surface.

Thus an extended linear characteristic region exists, said influence by a corresponding component or component selection factors must nature be matched. This vote can in principle by the use of a proportional magnet 26 again be calibrated appropriately thick. With increasing size of which increase the cost of the construction space required increases and the proportional solenoid 26 similarly high forces applying 26th proportional magnet must, accordingly high electrical services are clearly needed, ultimately the primary drive under fuel provides more consumption.

In the embodiment of the pilot piston 21 can be proposed here such a tare relatively easy adjustment of the effective control surface via a reach. The effective control surface results from the difference of the oürschnittsflächen 45a, 45b in the control chamber of the pilot piston 21 volts. As shown, the pilot piston 21 has on the side with the opening notch 44 equipped Ouerschnittsfläche a greater than on the opposite side with the split ring seals 45a incorporated on 43.

With a magnification between the larger and the smaller the Ouotienten (relative size) Ouerschnittsfläche 45a, 45b, the adaptation of the diameter in the corresponding length here by 42a, 42c of the pilot piston 21 is feasible simply, is a de-regulator characteristic by the present oil pressure in the control chamber increases by the proportional magnet 26 increasingly more outgoing force V is supported. In the latter case a greater pitch of the resulting current-to-pressure characteristic (see film 51). In contrast leads to a reduction of the said Ouotienten rising current-to-pressure characteristic (see figfig. 11) flat.

[0094] With a magnification between the larger and the smaller the Ouotienten (relative size) Ouerschnittsfläche 45a, 45b, the adaptation of the diameter in the corresponding length here by 42a, 42c of the pilot piston 21 is feasible simply, is a de-regulator with falling characteristic by the oil pressure in the control chamber V to a force on the pilot piston 21 applied this, the outgoing force by the proportional magnet 26 increasingly discourage. In the latter case results in a current-to-pressure characteristic (see figfig. 12) flatter. In contrast leads to a reduction of the current-to-pressure characteristic curve steeper Ouotienten said descending.

[0095] In the embodiment of the invention is a change in the size of the effective control surface 20a precursor of the pilot piston 21 determining size ratio with a comparatively low difference in production possible and concerns only the pilot piston 21 and stepped bushing 30. The pump housing 20d must not be altered, since the inner diameter of the pilot piston 21 to be changed for accommodation in the stepped bushing 30 are carried out.

[0096] The invention article, the presented here might also be used without a primary actuator 26 20a precursor, the precursor by a mechanically or manually transmitted by 20a - is actuated directly by an operator or by a simple foot moving mechanical driver is triggered. Then would be a influencing the transfer characteristic between the adjusting width of the operating lever and the pressure level at the high pressure outlet of the hydraulic pump by the described possibility of dimensioning the effective control surface in the control chamber of the pilot piston 21 V is an effective instrument.

[0097] With the listed embodiments can subsequently both with a current-to-pressure characteristic covered by the de regulator as well as those with a rising current-to-pressure characteristic are represented.

[0098] In the preceding embodiment according to figfig. 6 to 10 a stepped bushing 30 was used. But there is also the possibility, the controller 20 to operate without stepped bushing 30. A corresponding embodiment shows a longitudinal section of the pilot piston short range shown figfig. 13th for a DE regulator with falling characteristic. The control axle bore for the pilot piston 21 is carried out directly in the controller housing 50d. It is a bore 55 with airborne, because in view from the axial central region is a larger internal diameter than the controller axle bore 55b in the two remaining longitudinal sections 55a, 55c axle bore before the regulator. The pilot piston 21 has two radial grooves 29a, 29b, be displayed by the controller 50 in accordance therewith and the ensuing installation orientation at a characteristic characteristic these grooves 29a, 29b a circlip 28 can be placed. On the right end of the Figure is mounted in the controller axle bore 24 actuator, 25, in a larger inner diameter than the controller housing 50d accommodate them requires continued part of this regulator axle bore, wherein the pilot piston 21 is housed. This is a further movement of the pilot piston bore sections at the transition 21 due to the securing ring 29 in the direction for proportional magnet 26 mounted blocked. Although the left side of the plunger 27 to be detected does not contact the pilot piston 26 proportional magnet 21, is its zero position by the bias of the compression spring 24 is located on the right clearly defined. The section is further apparent, that the pilot piston 21 opening 44 has at least two notches.

[0099] The use of a stepped bushing 30 allows 100% identical parts for the two types of control strategy, i.e. the de regulator with a) rising and b) with falling characteristic. In terms of manufacturing a de-regulator in a version, the 30 has a stepped bushing, outweigh the advantages:

In the manufacture of a stepped bushing 30 can from a round material - apart from the longitudinal bores (these are the central longitudinal bore 35 for accommodating the pilot piston 21 and the at least one ölabflussbohrung 33) and the at least one radial bore and the stepped bushing 30 by rotating and thus by a marking - economical method are prepared.

(i) enters into the central longitudinal bore 35 a the radial bore. The burrs are removed thereby generated must drill very carefully.

(ii) the diameter of the longitudinal bore 35 high precision must be respected.

(III to) all inner and outer surfaces must be completely free of metal chips.

The requirements (I in), and (III to) can be much easier (II to) meet, as in the case of a stepped bushing when the controller housing is often handy component instead of comparatively larger 20d. Wherein the stepped bushing 30 absence, should this previously all processing steps inside the regulator housing and thus to 50d circumscribed for the machining tools clearly be made more difficult to access locations. Further quality control is a necessary Augenscheinnahme said processing positions inside the regulator housing 50d much more time-consuming and the risk of unrecognized shortcomings significantly higher.

In the controller housing for accommodating the stepped bushing 30 20d can the large part of the required material recesses with a comparatively high are produced under measure. It must only be ensured, that the stepped bushing 30 is fixed at the intended location.

(At least one ölabflussbohrung 33 would for both controller types are needed, because at a de-regulator with rising characteristic this connection for the function determining oil path is required and wherein a de-regulator with falling characteristic proportional magnet 26 on the side facing obtained leaked.) Wherein the corresponding incorporation of the necessary material cutouts, and compounds in the controller housing bearing surfaces 20d itself, could only 30 as a separate component and the stepped bushing for its installation in the controller housing 20d facilities required (the clamping components or a thread or screw connection.

the processing steps for the preparation an interference fit) omitted.

The external diameter of the pilot piston 21 by simple geometric adjustments and the inner diameter of the stepped bushing 30 a defined slope change the controller characteristic can be achieved.

[0100] In the preceding embodiment according to figfig. 6 to 10 was the pilot piston 21 provided with a stop, i.e. it was a pilot piston 21 with a at the corresponding radial groove 29a, 29b used circlip mounted 28.

[0101] The controller 20 would be even without the pilot piston stop 29 operatively. The presence of a stop 29 but offers two large advantages:

(i) with respect to its zero position (the position here is meant unbestromtem proportional magnet 26) takes the pilot piston 21 always a well-defined position.

(ii) at low current is the current force characteristic of a proportional magnet 26 strengthen nonlinear. In the adjusting unit is biased by the compression spring 24 present appropriate weight, can be achieved, only that their contraction in the linear region of the proportional magnet and therefore only in its linear characteristics used for the controller is used actuating range operation.

[0102] In the preceding embodiment according to figfig. 6 to 10 was the pilot piston 21 with an opening notch, an even contour, used. Alternatively here would be equally as possible a curved contour.

[0103] In the preceding embodiment according to figfig. 6 to 10 is the stepped bushing 30 with an off-hook carried out, whereby in their internal bore three longitudinal sections 35a, 35b, 35c each having different diameters shown. An alternative embodiment of the stepped bushing 30' is shown figfig. 14. Shown here the stepped bushing 30 'has no such removal, only why these two lengths 35a', 35b ' has different internal diameters. In the execution according to figfig. also has 6 to 10v erwendete pilot piston 21 on two opening notches 44, whereas the pilot piston 21 according to figfig. 14 only via a single opening notch 44' has. Further have the two pilot piston 21.21 ' on a different number of split ring seals 43.

[0104] The variant without removal of the stepped bushing 30 may be also implemented in the previously stated figfig. variant according to 13, wherein the controller housing with only two sections with different inner diameters the regulator 50d axle bore is configured.

[0105] Different embodiments of the stepped bushing 30 may of course just discussed, 30 'and the pilot piston 21.21' both in a de-controller in each increases a de-regulator with falling characteristic are used.

[0106] The number of notches may vary opening, see bspwbspw. figfig. figfig. 8 and 14.

[0107] The stepped bushing can by clearance fit, press fit or screwing 20d are mounted within the regulator housing. A clearance fit is preferably by spring-like elements, e.g. plate - or coil springs.

G of: marking the stepped bushing 30, 30'

[0108] As mentioned according to the importance of this concept is not decisive and marking function. The presence of this marking the large advantage however effected, that during assembly the required installation orientation simply is recognizable.

[0109] The guided features clearly under d to g can occur only variants, in which the controller 20 when in a configuration with a stepped bushing 30 is used 20a precursor.

It is a precursor 20a ' without stepped bushing, all permutations of all variants of features of b to d can then occur.

It is a precursor with stepped bushing 30 20a, then all permutations of all variants of features of b to g can occur.

[0110] (I) controller 20 with stepped bushing 30 and clearance fit

With respect to the representation and orientation of the figfig. 8:

The first controller axis bore of the spring plate 25 righthand are concerned, the compression spring 24 and the set screw provided with the oil seal into the controller housing 20d mounted. The securing ring 29 is then on that for the type of radial groove 29b of the pilot piston 21 provided de regulator placed. Thereafter these parts unit into said stepped bushing 30 used. The clamping elements for fixing the stepped bushing 30 are subsequently exposed to this. This enlarged parts of the left side coming into the relevant controller unit is used axle bore. The seal is provided with the proportional solenoid 26 closing, as the already assembled actuator for mounting passes, fixed on the controller housing 20d.

[0111] (Ii) controller 20 with stepped bushing 30 and press fitting or screwing

The stepped bushing 30 is first installed into the controller housing 20d. The pilot piston 21 depending on type of automatic controller must already with one of the right or left side of the securing ring 29 placed the relevant controller into its stop position in the already-installed from axle bore stepped bushing 30 are used. Mounting the actuator 24, 25 and 26 as described be proportional magnet (I in).

[0112] (III to) controller 50 without stepped bushing

Depending on the type of automatic controller 21 with the pilot piston ring 29 can already one of the right or the left side of placed the relevant controller into its stop position on the basis axis bore 50d controller housing are used. Mounting the actuator 24, 25 and 26 as described be proportional magnet (I in).

[0113] The constructive fundamental principle, a two-stage hydraulic regulator which previously for building the precursor 20a 20 with egg. Primary actuator 26 has been presented, may also on single stage, three-stage hydraulic valves or be applied etc controller. The presence of a non-hydraulic actuator 26 is optional primary. Instead of a primary hydraulic actuator 26 could also mechanically transmitted by a manual or foot moving 20a precursor - are controlled by a simple mechanical entrainment of the operator directly and are triggered.

[0114] The egg. 26 directly or a converted signal of a primary actuator can control lever/joystick obtained. Designated converted signal is meant, that in the simplest case the the egg. 26 Primary actuator signal supplied from a superposition between the output of the joystick and a characteristic curve is obtained. (Bspw. it may be advantageous for a specific application, a parabolic response characteristic knocking. the joystick stick position and the pressure level of the high-pressure output of the hydraulic pump to obtain, the hydraulic pump or the function to be performed in the lower drive area specifically it particularly delicate to use metered. In a further development stage by an additional dependent on system conditions and/superposition may be influenced or ambient conditions. (The latter could bspwbspw. are used, the stall as a primary drive combustion engine which serves to prevent. the superposition could be set by a software, A) the instantaneous rotation speed of the internal combustion engine is supplied via a sensor detected and B) a map of speed torque dynamics of the internal combustion engine is deposited. The software can be stored in a specially allocated here on an already existing controller or otherwise be implemented controller.)

[0115] Another example:

The de regulator is used, the power supply to a fan set actuated by a hydraulic motor. For supplying a primary function are briefly (e.g. for the traction drive about during start-up or a working tool about a lifting movement during insertion) particularly high performance needs, the hydraulic fan drive power supply could used make a Abregelung briefly de controller.

[0116] The invention article corresponding HydraulikventilsVReglers cannot only part of a component of a control as previously described, but also be part of a control loop. Here it is clearly irrelevant, whether the control loop exclusively from hardware components (hydraulic, electrical mechanism and) or whether the control loop is carried out additionally also includes software circumferences.

In case of application of the invention would in a regulation or even a complete article there a defect e.g. by damage to a sensor failure, by a software error, by a failure of the data communication or a signal interruption occur etc, to the proper selection of the de regulator type is a fail-safe strategy for supporting.

[0117] With the preferred embodiment are all components of such a pressure regulator 20 with identical positive and negative characteristic. A pressure regulator 20 already assembled with a comparatively low expense without a positive characteristic can exchange of components to a pressure regulator 20 with a negative characteristic are converted and vice versa.

This is possible by the addition of the stepped bushing 30 and its corresponding component designated as the particular design of the pilot piston 21 and the configuration and conceptual layout the hydraulic oil supply from the high pressure side represented coming from the displayed conceptual layout of the expiration of oil and the hydraulic oil return bore in the regulator housing 20d 20a outside the precursor, the precursor is applied which for 20a.

By the design and number of opening (s) contained in the pilot piston notch 44 can be influenced the response of the controller 20. As basic forms of design an opening notch 44 in its radial direction come into question: a straight shape, a convex shape, a concave shape and a mixture of any curved and straight forms generalized. The depth or the depth profile further can of course the pilot piston 21 and length of the opening notch 44 longitudinally varying. This notch 44 into the central opening may also strongly tapered longitudinal section of the pilot piston 21 42b project.

[0118]Astop 29 is advantageously provided for the pilot piston 21, whose position at a non-energization by the energizing of the primary actuator 26 or weak electrical indicate clearly. A particularly advantageous embodiment is the presence of a radial groove 29a, 29b on the pilot piston 21 is. The pilot piston 21 before installation can this in a clearly defined and well visible position locking ring 29 are placed. According to the strategy is equal to part 21 at two positions said radial groove on pilot piston 29a, 29b mounted. Depending on the type of automatic controller is required then the securing ring 28 mounted on the mating side. Of course said radial grooves 29a, 29b respectively mounted at a longitudinal position be precisely defined, since by this the zero current situation (concerning. the electric) current is determined. A locking ring 28 can be used also constructionally, must the groove depth, the placement on the side of the pilot piston 21 for the (slightly) larger outer diameter is provided, a slightly greater depth.

By applying correspondingly dimensioned and positioned in the region of the outer surface of the pilot piston 21 corresponding to radial grooves, the apart from a small leakage oil flow be sealingly - this is the side with the slightly smaller outside diameter can split ring seals are represented - 43, whereby this leakage can be considerably reduced; ideally Ouantität such a limit, just sufficient, for lubricating oil flow with the necessary to maintain safety.

Mention of a spring plate 25 is further, a compression spring 24, by a set screw which can be adjusted to different bias voltages, adjusting device formed, which in turn by a screw connection in the regulator housing 20d in which the control axis of the pilot piston 21 is installed opposite the bore 20a precursor representing. Provided on the adjusting device is a position, a seal can be placed on the clearly defined and visible. Once this setting device at the intended location in the regulator housing 20d with proposed tightening torque is screwed, is an oil-tight closure.

[0119] The primary actuator 26 can be provided at a position, a seal can be mounted on the clearly defined and visible. The primary actuator 26 is screwed on the controller housing. This connection between the regulator housing and is then the primary actuator 26 with the cooperation of the aforementioned seal 20d an oil-tight closure before, also within the precursor at high öldrücken 20a is effective.

[0120] The hydraulic pressure control unit 20 can in all Hydraulikreglern/invention - valves, independently thereof, whether these in mobile applications such as road vehicles, mobile working machines, ship building or in the field of aeronautical or in stationary applications are used. The new principle of valve can also be applied to the corresponding components of the pneumatic Hydraulikreglers/transmitted.