METHOD FOR CONTROLLING SCREW BACK PRESSURE OF ELECTRIC INJECTION MOLDING MACHINE
Figure 1 shows a back pressure control screw thereby, the cold air flows of the present invention 1 embodiment also atm cell transmission method in atm device together and blocks of a SUMMARY of a device shown in the injection mould machine shown is of the armoured. Also Figure 2 shows a screw back pressure control form that describes a behavior. Figure 3 shows a back pressure signal is back pressure screw also downward setpoint separation when the control form that describes a behavior. Figure 4 shows a back pressure signal is back pressure screw also separation upwardly setpoint when the control form that describes a behavior. Figure 5 shows a monitor time of screw back pressure signal is indicative of a variation in the described. Figure 6 that describes a form control back pressure screw is flow chart. Figure 7 screw back pressure signal is back pressure setpoint separation downward that describes a form control when the is flow chart. Back pressure signal is back pressure screw Figure 8 separation upwardly setpoint that describes a form control when the is flow chart. (Described code) 10 injection device 13 screw 14 servo motor 15 molten resin 18 ball-unt 19 ball screw 21 load cell 22 axis 23 motor 30 control device 31 back pressure set value 32 monitoring time setting value 34 number 2 retracted set value speed command value 33 number 1 retracted 35 compared, calculator 36 diverting means 38 additional speed command value 40 screw back pressure signal 43 number 2 stroke 42 number 1 stroke 46 47, 48 conversion time constant speed differrences PL, PH the upper limit threshold-PL, -PH lower limit threshold The present invention refers to, electric injection molding machine screw in plasticizing ([...]) relates to back pressure control method. The method control back pressure screw of the existing method, a melt caused by plasticizer due to resin pressure linearly moving a screw the retracted and imparts rotational motion is converted to, a rotated thereby or rotation the slightest rotational force is of servo-motor to open the controls the amount. The revolutions resulting in control, electrically force retracted or a screw pressure molten material changed according to a screw back pressure force over the set value force back pressure screw go/no-go by a rope. feedback controls servo motor (for example, . reference patent document 1). Also, a control of rotation amount, that detects and that pressure applied to the resin, with pressure and the determined back pressure setting uses an averaging filter difference, a servomechanism controlling the servo motor driving said circuit setting back pressure and the determined pressure difference with a charge pump outputs current command mobile according to backpressure so as to be back pressure setting by a rope. feedback control (for example, . reference patent document 2). As yet a further technique, detecting resin pressure is made equal to the back pressure setting moving speed of the screws such that the head portions feedback control the, establishment of a servo motor depending on the value of override speed command by user wants to, side of the circumferential surface of the continuous screw retract. moved (for example, . reference patent document 3). (Patent document 1) Japanese [...] 61-31221 call Official Gazette (number 1-3 page, also number 1-5) (Patent document 2) Japanese [...] 4-249129 call Official Gazette (number 1-7 page, also number 1-8) (Patent document 3) Japanese [...] 2-12002O call Official Gazette (number 1-5 page, also number 1-2) Yet it is also lockable, patent document 3 to patent document 1 is all of the existing method screw back pressure control method is by feedback control, , P a gain proportional but of course, a gain integrator I, and a fine-grained gain a is a frame counter requires for measuring of D. These PID constants in order to improve a control accuracy, high as possible is groove is in a long circle shape value. However, injection molding is extremely many types of resin material because the applied to, the resin material guarantees the fluidity of a width of or melting characteristics large. Formed to be opposite to each other, a PID average the lower end of the expecting resin material, by the refrigerant cooling means is too gain in any resin material, and low in and is seen in the control accuracy, by the refrigerant cooling means is too gain in material is made of a different resin from becoming unstable high leg muscles are vibration and control occurs poses problems, such as a strong. The present invention refers to, said techniques of the existing method to solve problems within as offered, despite is not the feedback control as control ON-OFF, a simple structure than has the inclined ejection holes and a feedback control accuracies material provides an electric injection molding machine screw back pressure control method by a rope.. I.e., claim 1 of the invention refers to, screw backpressure there is a sensor and detects, as the electrical signal, a servo motor and driving rotating step screw, driving screw a motor and a plasticizing and the material, said servo motor and a control device to control the at least one motor said with motorised method for controlling back pressure screw injection molding machine in, said control device, said screw and the plasticizer which rotate motor back pressure signal is back pressure setpoint number 1 rotate to a slower moving screw when retracted speed command by a control the rotation of said servo motor number 1 stroke and, screw back pressure signal is back pressure setpoint large number 2 rotate at a high speed a screwed onto the casing retracted speed command by a control the rotation of said servo motor number 2 stroke repeated to back pressure control screw injection molding machine characterized by electric relates to method. Claim 2 of the invention refers to, according to Claim 1, monitoring a predetermined stroke said number 1 continue by disposing a exceeds 48 hours when, said number 1 retracted speed command value in which additional speed command pressure minus a value number 1 number 1 by operation and executes a lifting stroke, said number 2 value operation said number 1 said number 1 retracted speed command value in a speed command retracted pressure minus a speed difference obtained by adder number 2 number 2 by operation an electric injection molding machine executes a lifting stroke relates to screw back pressure control method. Claim 3 of the invention refers to, according to Claim 1, said number 2 stroke a predetermined monitoring exceeds 48 hours when continue by disposing a, said number 2 retracted speed command value speed command value operation by using the sum of the number 1 and number 2 executes a lifting stroke, said number 2 retracted said number 1 retracted speed command value in a speed command pressure minus a speed difference obtained by subtracted from value operation said number 1 number 2 number 1 by operation an electric injection molding machine executes a lifting stroke relates to screw back pressure control method. Claim 4 of the invention refers to, according to Claim 1, said number 2 or stroke said number 2 from stroke said number 1 from stroke to stroke said number 1 a translation value speed command retracted, predetermined temporal variations of a an electric injection molding machine is performed based on the method relates to screw back pressure control. Claim 5 of the invention refers to, according to Claim 1, said monitoring time said signal is back pressure screw said back pressure set value is changed in accordance with to such extent that it is separation in an electric injection molding machine relates to screw back pressure control method. Claim 6 of the invention refers to, according to Claim 5, said screw back pressure signal is said back pressure set value from a heavy separation when the monitoring time, said screw back pressure signal is said separation slightly in back pressure set value is smaller than that of the monitoring when the an electric injection molding machine relates to screw back pressure control method. (Form of the invention embodiment) Drawing based on. rapidly and to reduce a memory form of the present invention embodiment. Figure 1 shows a screw thereby, the cold air flows of the present invention 1 embodiment also blocks of atm cell transmission method in atm back pressure control device and with injection of injection molding machine be also of the armoured shown a SUMMARY of a device, that describes a form control back pressure screw Figure 2 as further operations, back pressure signal is back pressure screw Figure 3 separation downward setpoint that describes a form control when the as further operations, back pressure signal is back pressure screw Figure 4 separation upwardly setpoint that describes a form control when the as further operations, Figure 5 monitoring time of screw back pressure signal changes to descriptive also, that describes a form control back pressure screw Figure 6 flow chart , Figure 7 screw back pressure signal is back pressure setpoint separation downward that describes a form control when the flow chart , 8 the screw back pressure signal is back pressure setpoint upwardly separation when the is flow chart that describes a form control. Device (10) an injection mould machine embodiment of the present invention the, servo motor (15, 15) by screw (13) advances a molten resin (14) it is shown a the support member, and filling the injected into the mould tools which do not allow, motor (23) by screw (13) by rotating a raw material resin plasticize, kneading, melting thermoplastic resin or thermosetting resin injection molding is used an electric injection device. Screw (13) heating barrel (12) rotation, and is embedded according to the invention a moveable reciprocating, the heated inner tube of furnace for LPCVD process barrel heating means is provided (12), cooperates with a raw material resin plasticize, kneading, molten resin serves (14) to. And, molten resin (14) has a plunger forward as a screw (13) the nozzle by (11) mold (not shown) through injection-charging is. Heating barrel (12) the nut (17) the housing by the (16) and secured to, screw (13) consists of an upper (22) is fixed to a.. Axis (22) a connection semi (20) bearing (27) supported by provided. Connected semi (20) secured to both ends of ball-unt (19, 19) has a ball screw (18, 18) and a screw bind to and, ball screw (18) the housing (16) secured to servo motor (15) is connected to the rotor of. Axis (22) having semi connected (20) inside as a result of form bringing up for discussion of screw (13) a curved wedge is molten resin (14) determining the pressure as a sensor load cell (21) bonded thereto and presenting, is as a result of form bringing up for discussion end screw (13) is driven by a motor (23) and is firmly bonded, its rotor, and the an axis (22) is connected to the. Motor (23) preferably the servo inductive but preferably such that. Control device (30) is typically constructed from a to a microprocessor has, injection device (10) or the clamping device not shown such as injection molding machine or-action sequence speed actuator, force, position and such as a temperature and the like to control. In Figure 1 shows a control device functionally only and which are involved in the present invention is in. Back pressure set value (31), monitoring time setting value (32), number 1 retracted speed command value (33) and number 2 retracted speed command value (34) the, each alone device (30) or control whether setting a backpressure set in the operating section of the set value (31) based on calculated with a CPU containing to ROM or RAM in.. Furthermore, number 2 retracted speed command value (34) the, as refers to, determined from measured value of the speed retracted screw one. Yet, operation part, CPU, the ROM and RAM of publicly known, which does not require a pair of holders and the panel is shown and described.. Compared, calculator (35) the load cell (21) from screw back pressure signal, back pressure set value (31) and monitoring time setting value (32) is the input. Compared, calculator (35) calculated value is compared they match, the result conversion signal diverting means (36) outputs the to. Diverting means (36) the number 1 retracted speed command value (33), number 2 retracted speed command value (34), and number 1 retracted speed command value (33) and number 2 retracted speed command value (34) added to speed command value (38) is values are input, it buys grudge posterization, line structure or gray scale. Diverting means (36) the, compared, calculator (35) of converted signals by said plurality of command of selecting one delayer, the selection a signal to the servo amplifier (37) outputs the to. Servo amplifier (37) has servo-motor (15, 15) performs feedback control of device is of publicly known for. The servo amplifier (37) the diverting means (36) a retracted selected by speed command values are input, simultaneously, servo motor (15, 15) for driving encoder axis (24, 24) is input position signals from. Furthermore, servo motor in embodiment is (15) a with a the 2, each servo motor (15, 15) the operation control quantum is synchronized to supply an electrical current servo amplifier (37) 2 to on a common mounting a. Also, a plurality of micro injection device 1 for servo motor (15) to process images and one. Furthermore, action on the basis of 8 also to 2 also relates to. Said injection device (10) advancing a, nozzle (11) is shown that is brought into contact with a to the mould tools which do not allow, said motor (23) and starts a a screw (13). rotating the. Therefore, also shown in 6 of a resin material including a disclosure of plasticizer (S10). Heating barrel (12) to rotate in a screw (13) resin a molten, molten resin with a consequent kneading (14) is, molten resin (14) heating barrel (12) in screw (13) urged in front of.. Nozzle (11) by lifting a urban the mould tools which do not allow so as to, the nozzle (11) in which tip of opening of former time is blocked by a resin injection. Therefore, the circular pipe (13) a molten resin containing a urged the (14) based on pressure as to redirect the reaction forces performed by the sliding of the guide occurs and the reverse movement to the linear, the force the screw back pressure signal (40) as load cell (21) is detected in (S11). Said mobile performed by the sliding of the guide force of the retraction direction a screw (13) the position of the, servo motor (15) encoder of (24) or a separate position sensor is detected to provided. Screw (13) the position of the, is chosen on the basis of the volume of the article previously been molded of a plasticized metering compare calculated with a, screw (13) metering plasticizing is moved: it is determining their arrival at locations (S12). In S12 is said screw (13) metering plasticizing is if the result of the determination is that the object reaches the required position, motor (23), the rotation of the plasticizing is is terminated. On the other hand, screw in said S12 (13) is plasticizing metering their arrival at locations if the result of the determination is not to be, of the present invention ON-OFF and closed by the control of the screw (13) to its retracted of performing speed control a screw back pressure signal (40) is back pressure set value (31) controls the is provided in proximity of a. the chemical engineering very middle plasticizer, said compared, calculator (35) a screw back pressure signal (40) is back pressure set value (31) a cleaning tank 5 is raised up a whether or not the input (S13) the comparison operation. In S13 is screw back pressure signal (40) is back pressure set value (31) when not a cleaning tank 5 is raised up, i.e. said screw back pressure signal (40) is back pressure set value (31) when the oxygen storage amount is smaller than and the rotating shaft jumps of e-caprolactam S16, refers to to a low screw (13) retract the number 1 retracted speed command value (33) by said servo motor (15, 15) for controlling the rotation of a number 1 stroke (42) continues a. On the other hand, screw in said S13 back pressure signal (40) is back pressure set value (31) when a cleaning tank 5 is raised up, i.e. said screw back pressure signal (40) is back pressure set value (31) opened not to much even if a a comparison, calculator (35) is switched from one to another means (36) and switches signal, connection terminal (53) a connection terminal (54) changed to the. Therefore, said servo motor (15, 15) control a screw (13) number 2 rotate at a high speed a retracted speed command value (34) is converted into speed control based on (S14). And, said servo motor (15, 15) rotation of servo amplifier (37) through said number 2 retracted speed command value (34) controlled by number 2 stroke (43) is performed. Screw (13) by at high speed retraction of, molten resin (14) pressure i.e. screw back pressure signal (40) is lowered to.. Furthermore, in S15 said compared, calculator (35) is said screw back pressure signal (40) is back pressure set value (31) or not (S15) the comparison operation: it. In S15 is screw back pressure signal (40) is back pressure set value (31) or not the time for not, said number 2 stroke they are moved back to S14 (43) continues a. On the other hand, said S15 in screw back pressure signal (40) is back pressure set value (31) or not when the, compared, calculator (35) is switched from one to another means (36) and switches signal, connection terminal (54) a connection terminal (53) changed to the. Therefore, said servo motor (15, 15) control a screw (13) to a slower moving rotate number 1 retracted speed command value (33) is converted into speed control based on (S16). And, said servo motor (15, 15) rotation of servo amplifier (37) through said number 1 retracted speed command value (33) controlled by number 1 stroke (42) is performed. Then and returned into said S2, screw (13) is, until it reaches a position metering plasticizing said number 1 stroke (42) and said number 2 stroke (43) an alternate repeatedly, screw back pressure signal (40) is back pressure set value (31) controls the is provided in proximity of a. Screw as said back pressure signal (40) is control ON-OFF the control of a, as shown in also 2, said screw back pressure signal (40) the back pressure set value (31) with respect to two non vibrates. Furthermore, said screw back pressure signal (40) a control of feedback control so, said screw back pressure signal (40) upon the raw material resin plasticizer in screw (13) the rotational load of variations and such a control on. susceptible to disturbance. Therefore, screw back pressure signal (40) is back pressure set value (31) from separation which is detected, screw back pressure signal (40) a back pressure set value (31) controls the parameters such that the priority parameters approach. First, screw back pressure signal (40) is back pressure set value (31) downwardly from separation when 7 and 3 also control of the described based on. Plasticizer and the, control device (30) during the use of the stroke the number 1 (S17), screw back pressure signal (40) is back pressure set value (31) downwardly from the GPS number 1 portion of the cycle of continuing time a predetermined monitoring time setting value (32) exceeds continue by disposing a:it. is used to judge whether the (S18). Continuing time portion of the cycle of number 1 in S18 is a predetermined monitoring time setting value (32) exceeds when not continue by disposing a, said S17 is wrapped back around to a number 1. is the entire water is smaller. While, a predetermined continuation time portion of the cycle of number 1 in said S18 monitoring time setting value (32) exceeds continue by disposing a which is detected, said number 1 retracted speed command value (33) in which additional speed command value (38) number 1 operation by pressure minus a number 1 (S19) and executes a lifting stroke, said number 2 retracted speed command value said number 1 operation value (34) in said number 1 retracted speed command value (33) speed differrences pressure minus a (46) obtained by adding number 2 number 2 by operation. executes a lifting stroke (S20). I.e., also as shown in 1, diverting means (36) whereat the conductive surfaces form contact terminals (51) and a connection terminal (52) eliminate the by a rope. control of a switch of the switch unit. Furthermore, in said S19 in stroke number 1 number 1 number 1 operation value retracted speed command value (33) is is deemed as, the number 1 stroke also said S18 same and currently running on the judgment is made, as shown in 3 also, S19 of processing are continuously one. Therefore, screw back pressure signal (40) back pressure set value (31) in downward separation depending on the degree of additional speed command value (38) additional recovery are controlled, screw back pressure signal (40) back pressure set value (31) in downward separation the recording operation. is modified. Yet, said number 1 number 2 value and operation device (30) control value operation device temporary storage of a CPU stored to RAM is carried out by using an operation. Furthermore, screw back pressure signal (40) is back pressure set value (31) upward from the separation when 8 and 4 also control of the described based on. Plasticizer and the, control device (30) during the use of the stroke the number 2 (S21), screw back pressure signal (40) is back pressure set value (31) upward from the continuing time portion of the cycle of number 2 the GPS a predetermined monitoring time setting value (32) exceeds. is used to judge whether the unrequired electromagnetic waves continue by disposing a (S22). Continuing time portion of the cycle of number 2 in S22 is a predetermined monitoring time setting value (32) exceeds when not continue by disposing a, number 2 a is wrapped back around to said S21 and executes the so X the water is smaller. While, a predetermined continuation time portion of the cycle of number 2 in said S22 monitoring time setting value (32) exceeds continue by disposing a which is detected, said number 2 retracted speed command value (34) added to speed command value (38) using the sum of the number 1 number 2 by operation (S23) and executes a lifting stroke, said number 2 retracted speed command value (34) in said number 1 retracted speed command value (33) speed differrences pressure minus a (46) for said number 1 number 2 obtained by subtracted from value operation by operation. executes a lifting stroke number 1 (S24). I.e., also as shown in 1, diverting means (36) whereat the conductive surfaces form contact terminals (56) and a connection terminal (55) eliminate the by a rope. control of a switch of the switch unit. Furthermore, in said S23 in stroke number 2 number 1 number 2 retracted speed command value operation value (34) is is deemed as, the number 2 stroke also said S22 the same the currently running on the judgment is made, also as shown in 4, S23 for treating for continuously performed. Therefore, screw back pressure signal (40) back pressure set value (31) upward separation depending on the degree of additional speed command value (38) additional recovery are controlled, screw back pressure signal (40) back pressure set value (31) upward separation the recording operation. is modified. Yet, operation value and said number 1 number 2 operation value control device (30) with a consequent RAM device temporary storage of a result of the judgment shows that the CPU is carried out by using an operation. State of the SP heads and, also, as shown in 1 diverting means (36) by number 1 retracted speed command value (33) and number 2 retracted speed command value (34) with instantaneous conversion. is carried out. Yet it is also lockable, such directives signal of the screw for the conversion of (13) varying more abruptly to retraction of speed. Thus molten resin (14) pressure i.e. screw back pressure signal (40) that suddenly fluctuates and, said screw back pressure signal (40) a screw back pressure set value (31) over the cutaway portions is goal under or goal. In order to provide protection against same, also 2 as represented by 47, 48 code in, number 1 retracted speed command value (33) from number 2 retracted speed command value (34) number 2 or conversion to retracted speed command value (34) from speed command value number 1 retracted (33) conversion to predetermined is executed based changes. Here, said temporal variations of a predetermined conversion when using gradually changes the integer, is effective. Raw material resin the value of said time constant or plasticizing-of-limits condition is preferably set-up changing the, properly strengthened by. Yet, number 1 retracted speed command value (33) from number 2 retracted speed command value (34) number 2 or conversion to retracted speed command value (34) from speed command value number 1 retracted (33) the conversion to, time constant is a not an n-number and linear or any curved shape temporal preferably even when reading the picture on the based on the detected changes. Furthermore, the in Figure 2, number 1 retracted speed command value (33) from number 2 retracted speed command value (34) conversion to time constant (47) is number 2 retracted speed command value (34) from speed command value number 1 retracted (33) conversion to time constant (48) the same value have been exemplary a moment when a, according to situation of plasticizing amount conversion time constant (47, 48) for different the. Yet, said set value such as switching of control to change a time, 4 and 3 also shown in a screw back pressure signal (40) is back pressure set value (31) from control when the separation can be uses the even. Screw back pressure control the second as other method, said monitoring time setting value (32) of correction control.. This corrected control, monitoring time (monitoring time setting value (32)) the screw back pressure signal (40) is said back pressure set value (31) according to separation from to such extent that it is. is to change the. Here, said screw back pressure signal (40) is said back pressure set value (31) when the separation greatly from monitoring time (monitoring time setting value (32)) the, said screw back pressure signal (40) is said back pressure set value (31) when the separation succeeded in keeping from monitoring time (monitoring time setting value (32)) so as to is smaller than that of the. Also as shown in 5, back pressure set value (31) number 1 of lower limit threshold (-PL) and a number 1 the upper limit threshold (PL) consisting of width (W1) and monitoring number 1, number 2 lower limit threshold (-PH) and a number 2 the upper limit threshold (PH) consisting of monitoring width (W2) is provided on the number 2. And, screw back pressure signal (40) for monitoring time setting value (32), a change in, number 1 number 2 monitoring width (W2) monitoring width (W1) and width (W1) between monitoring number 1 number 2 from monitoring width (W2) toward the which shading is reduced and proportional relationship, number 1 monitoring width (W1) in range of said monitoring time setting value (32) in the is monitored width (W1) using a predetermined value and constant by means of the heating, number 2 monitoring width (W2) in out of a range of said monitoring time setting value (32) the is monitored width (W2) using a predetermined value in a constant by means of the heating. Furthermore, width (W1) without monitoring number 1, number 2 are installed on the upper surface of only monitoring width (W2), monitoring time setting value (32) for said back pressure set value (31) and number 2 monitoring width (W2) between said back pressure set value (31) width (W2) toward the monitoring number 2 from being shorter if the proportional relationship may preferably. Furthermore, screw back pressure signal (40) for monitoring time setting value (32), a change in, said proportion relation with a such as any rather than from being converted by a curved line may preferably. Here, said number 1 monitoring width (W1) between said number 2 and monitoring width (W2), said monitoring time (monitoring time setting value (32)) for, said screw back pressure signal (40) is back pressure set value (31) by being shorter if the GPS from according to a modified to. Therefore, degree of freedom in the wall of the container body to the monitoring time said back pressure set value (31) to a screw back pressure signal (40) to modify the of separation between the, control of back pressure screw can be the same time, can realize good. Here, set value of actual in the exemplary of the present invention in the embodiment. For retracted speed command value, back pressure set value (31) from one network to another with reduced set up so that screw back pressure is low and when the motor (23) setting the rotation speed of screw set up so that high value (13) when the rpm of the when high, faster than said screw (13) around an axial line control of back pressure screw is preferred in that a efficient to. Formed to be opposite to each other, number 2 retracted speed command value (34) the screw back pressure control screw a measured value of the back pressure signal (40) based on is determined. Specifically, is determined as follows. First, said screw (13) the retracted so as not to servo motor (15, 15) rotating speed of Figure 0 of one part and a second control state, screw (13) by rotating a disclosure a a by volume of plasticizing resin material. And, screw back pressure signal (40) is raised back pressure set value (31) when a cleaning tank 5 is raised up screw (13) is detected speed retraction of. A control speed recesses detecting device (30) number 2 retracted set value of temporary storage device (RAM) to (34), is stored as. Said speed difference (46) for example an every second for and set as a 2 millimeter, said CPU based on this value number 1 is retracted set value (33). subjected to the arithmetic process, thereby. Other settings value, additional set value (38) for every second for 0.1 millimeter, monitoring time setting value (32) for 1 ∼ 2m seconds, ± 1 MPa monitoring width (W1) of number 1, number 2 monitoring width (W2) of ± 5 MPa, was S. 2m time constant. The present invention refers to a embodiment and are not limited aspect, an RC has been of the invention within such a range that causes no deviating form the various modified by the can be the embodiment. Describes such as the shown or more, claim 1 of the invention refers to, screw back pressure signal is back pressure setpoint number 1 rotate to a slower moving screw when retracted speed command by a control the rotation of said servo motor number 1 stroke and, screw back pressure signal is back pressure setpoint large number 2 rotate at a high speed a screwed onto the casing retracted speed command by a control the rotation of said servo motor number 2 an electric control repeatedly stroke back pressure control screw injection molding machine is method. According to the control method, despite is not the feedback control as control ON-OFF, a simple structure than has the inclined ejection holes and a feedback control accuracies material. Claim 2 the invention refers to of, monitoring a predetermined stroke said number 1 continue by disposing a exceeds 48 hours when, said number 1 retracted speed command value in which additional speed command pressure minus a value number 1 number 1 by operation and executes a lifting stroke, said number 2 value operation said number 1 said number 1 retracted speed command value in a speed command retracted pressure minus a speed difference obtained by adder number 2 number 2 by operation executes a lifting stroke is an electric injection molding machine screw back pressure control method. According to the control method, screw back pressure signal back pressure set value in downward separation depending on the degree of additional speed command value additional recovery are controlled, said screw back pressure signal said back pressure set value can modify the in downward separation. Claim 3 of the invention refers to, said number 2 stroke a predetermined monitoring exceeds 48 hours when continue by disposing a, said number 2 retracted speed command value speed command value operation by using the sum of the number 1 and number 2 executes a lifting stroke, said number 2 retracted said number 1 retracted speed command value in a speed command pressure minus a speed difference obtained by subtracted from value operation said number 1 number 2 number 1 by operation executes a lifting stroke is an electric injection molding machine screw back pressure control method. According to the control method, screw back pressure signal back pressure set value upward separation depending on the degree of additional speed command value additional recovery are controlled, said screw back pressure signal back pressure set value can modify the upward separation. Claim 4 of the invention refers to, said number 2 or stroke said number 2 from stroke said number 1 said number 1 from stroke to stroke prevention value retracted speed command based on predetermined temporal variations of a screw which is executed electric injection molding machine is back pressure control method. According to the control method, screw back pressure signal over or goal under control of the goal may be not greater.. Claim 5 of the invention refers to, said monitoring time set value from said screw back pressure signal is said back pressure according to an electric change the separation to such extent that it is back pressure control screw injection molding machine is method. According to the control method, a screw for said back pressure on the back pressure signal and of separation between the, screw back pressure control of and can be preferred. Claim 6 of the invention refers to, said screw back pressure signal is greatly from said back pressure set value when the monitoring time separation, said screw back pressure signal is said back pressure set value monitoring when the separation X-shaped supporting plate is smaller than that of the back pressure control method is an electric injection molding machine screw. According to the control method, having degree of freedom in time monitoring said back pressure on the so as to for a screw back pressure signal to modify the of separation between the, control of back pressure screw can be good. PURPOSE: A method for controlling the screw back pressure of an electric injection molding machine is provided to stably obtain the control precision the same as the control precision of feedback controlling with simple structure. CONSTITUTION: A controller(30) of an electric injection molding machine repeats a first process of controlling the rotation of servo motors(15) by a first backup speed command value(33) for backing up a screw(13) at a low speed when a screw back pressure signal is lower than a reference back pressure value(31) during a plasticizing process and a second process of controlling the rotation of the servo motors by a second backup speed command value(34) for backing up the screw at a high speed when the screw back pressure signal is higher than the reference back pressure signal. © KIPO 2005 Screw backpressure there is a sensor and detects, as the electrical signal, a servo motor and driving rotating step screw, screw rotationally driving the disc-shaped recording a motor and a plasticizing an a then, the raw materials, said servo motor and a control device to control the at least one motor said with motorised method for controlling back pressure screw injection molding machine in, Said control device a, said screw and the plasticizer which rotate motor back pressure signal is back pressure setpoint number 1 rotate to a slower moving screw when retracted speed command by a control the rotation of said servo motor number 1 stroke and, screw back pressure signal is back pressure setpoint large number 2 rotate at a high speed a screwed onto the casing retracted speed command by a control the rotation of said servo motor number 2 stroke by repeating the control method characterized by electric back pressure control screw injection molding machine. According to Claim 1, monitoring a predetermined stroke said number 1 continue by disposing a exceeds 48 hours when, said number 1 retracted speed command value in which additional speed command pressure minus a value number 1 number 1 by operation and executes a lifting stroke, said number 2 value operation said number 1 said number 1 retracted speed command value in a speed command retracted pressure minus a speed difference obtained by adder number 2 number 2 by operation to executes a lifting stroke method characterized by electric back pressure control screw injection molding machine. According to Claim 1, said number 2 stroke a predetermined monitoring exceeds 48 hours when continue by disposing a, said number 2 retracted speed command value speed command value operation by using the sum of the number 1 and number 2 executes a lifting stroke, said number 2 retracted said number 1 retracted speed command value in a speed command pressure minus a speed difference obtained by subtracted from value operation said number 1 number 2 executes a lifting stroke number 1 by operation to screw back pressure control method characterized by electric injection molding machine. According to Claim 1, said number 2 or stroke said number 2 from stroke said number 1 from stroke to stroke said number 1 a translation value speed command retracted, predetermined temporal based on the detected changes executed method characterized by electric back pressure control screw injection molding machine. According to Claim 1, said monitoring time said signal is back pressure screw said separation from back pressure set value according to a degree of changes in ECG method characterized by electric back pressure control screw injection molding machine. According to Claim 5, said screw back pressure signal is greatly from said back pressure set value when the monitoring time separation, said screw back pressure signal is said back pressure set value when the separation X-shaped supporting plate is smaller than that of the monitoring to form a back pressure control screw injection molding machine characterized by electric method.
