CONTROL FOR ELECTRO-PNEUMATIC BRAKE

The invention concerns a control consisting for an electro-pneumatic brake, in particular booster brake of rail-mounted vehicles, of an electro-pneumatic brake valve and an electro-pneumatic release valve, and preferably a pressure control valve, a pressure intensifier and a bleed valve, whereby in a Bremsstromkreis an electrical operating organ of the electro-pneumatic brake valve and a switching contact are arranged in series, and in a release Rome circle an electrical operating organ of the electro-pneumatic release valve and both a switching contact and an electrical Selbsthaltteinrichtung in series it is arranged, whereby the switching contact of the release Rome circle and the electrical self retaining mechanism are to each other joined in parallel. la in particular in the tandem processing of locomotives as well as at arbitrary number of flight compartments of a traction vehicle it is simplest to steer a booster brake on electrical way. To the place of the pneumatic Führerbremsventile step electrical switching contacts, which are connected with electro-pneumatic valves by an electrical control unit, which are in a so-called electro-pneumatic auxiliary brake unit and which electrical instructions convert in the long run into Bremszylinderdruek. The electrical commands for brakes, release and automatic release from the flight compartment of a locomotive and/or a traction vehicle out take place in practice by means of the switches of a so-called five-position rocker switch, with a rastierten Vollbremsste! lung, a neutral position and positions for brakes, release as well as automatic release. The electrical control unit is in such a manner trained thereby that a brief locking of a switching contact of the five-position rocker switch causes a complete loosening of the brakes in the position for automatic release over an electro-pneumatic release valve, how this automatic release action only by a Bremsste! lung the five-position rocker switch, thus with the introduction of brake applications, one terminates. When well-known controls this is reached by a self retaining mechanism with an electromechanical auxiliary relay and a hold circuit, whereby the auxiliary relay is held after brief InsteIIungbringen of the five-position rocker switch into the position for automatic release over a hold circuit so for a long time under tension and so that over a elektropneumatisehes release valve a loosening of the brakes causes, until the hold circuit is interrupted by a Instellungbringen of the five Stellungskippsohalters into the brake position and such dropping the auxiliary relay causes, so that the automatic release action is terminated. The disadvantage of such a control with a self retaining mechanism and an auxiliary relay consists of that the contacts of the electromechanical auxiliary relay are subject to mechanical wear and lose thus also in the course of the time at switching security. The task of the invention consists from there of creating a control for electro-pneumatic brakes with which the disadvantage specified above is avoided and which by a favorable purchase price is characterised. This is solved according to invention thereby that the electrical self retaining mechanism consists of a thyristor, whose anode and cathode lie parallel to the switching point of the Lösestromkreisos and whose control port over a further switching contact is controllable, and that in series with the switching contact of the release Rome circle and parallel to anode and cathode of the thyristor at least electrically, a voltage drop causative construction unit is arranged, at that the Spannungsabfal! is larger than the voltage drop between anode and cathode of the leading thyristor. The advantages of a thyristor are in the contactless circuit, which is not subject to mechanical wear. In addition thyristors are smaller and cheaper than the relays used so far. The invention insists however not only in substitution of an electromechanical auxiliary relay by a thyristor, but in a special gate circuit, whereby in particular on the reaction of the operating circuit for the electro-pneumatic release valve on the controlling of the thyristor consideration was to be taken. The invention is more near described below on the basis the designs by remark examples to be limited ohhe to it. Fig.1 the Sehema of an electro-pneumatic auxiliary brake unit, Fig.2 the connection diagram of a remark example of the control and Fig.3 according to invention the connection diagram of a further remark example according to invention shows. The usual electro-pneumatic auxiliary brake unit represented in Fig.1 consists ektropneumatischen brake valve of the e] --1-- and the e] ektropneumatischen Löseventi] --2--, furthermore from a pressure control valve --3--, which is adjusted according to the maximum brake cylinder printing, one between feeder --4-- and Bremszyllnderleitung --5-- arranged pressure intensifier --6--, that, according to Bremsund release impulse elektrepneumatischen Bremsund of release valve, compressed air into the brake cylinder line --5-- and/or the brake cylinder line steers --5-- aired out, as well as a bleed valve -7--, which possible leakages of the electro-pneumatic brake valve --1-- in the free to divert lets. From the connection diagram in accordance with Fig.2 are three switches --I, II, III-- evidently, which correspond to the positions brakes, release and automatically release of a five Stellungskippsehalters. In the Bremsstromkreis lie from a coil --SP1-- existing operating organ of the electro-pneumatic brake valve --1-- and in series in addition the Schaltkentakt --l/1 -- the switch trained as change over switches --I--. In the release Rome circle lie from a coil --SP2-- existing operating organ of the electro-pneumatic release valve --2-- as well as in series in addition on the one hand the diodes --D--, the switching contact --II/1 -- the switch --II-- and the switching contact --I/1 -- the switch --DL--, on the other hand the Anodo --A-- and cathode --K-- the thyristor --Th-- and the switching contact --l/1 -- the switch --I--, whereby the control port --G-- over the switching contact--III [-- the switch --III-- one wires. The change over switch --I-- is in Fahrtund Lösestellung, if its first switching contact --l/1 -- closed and its second --I/2 -- is open. Thus is the coil --SP1-- the electro-pneumatic brake valve --1-- excited, whereby the electro-pneumatic brake valve represented in Fig.1 --1-- on its seat and such introducing the pressure of the feeder locks --4-- into the brake cylinder line prevents. Only in the brake position of the change over switch --I--, with its first switching contact --I/1 -- openly and its second --I/2 -- , becomes the coil is closed --SP1-- the electro-pneumatic brake valve --1-- dead, whereby a feather/spring the electro-pneumatic brake valve represented in Fig.1 --1-- opens and so the brake applications introduces. The advantage of a such brake valve working according to the quiescent current principle is in that with complete power failure in any case a braking is introduced and so a failure of the brakes is prevented. By the duration of the Instellungbringens of the change over switch --I-- into the brake position the brake cylinder printing up to maximum pressure can be increased steplessly, whereby when dropping the elektropneumatisehen brake valve --1-- arising voltage peaks by the protection diode --DL-- are compensated. Is the change over switch --I-- in Fahrtund Lösestellung, then is with locking of the switching contact --II/1 -- the release Rome circle the coil --SP2-- the electro-pneumatic release valve --2-- excited, whereby compressed air from the brake cylinders can divert into the atmosphere. By the duration of the locking of the switching contact --II]-- the release Rome circle can gradate in such a way! OS the braking action to be waived, whereby with the waste of the electro-pneumatic release valve --2-- arising voltage peaks by the protection diode --D2-- are compensated. Is the change over switch --1-- in Fahrtund Lösestellung, then can by brief closing of the switching contact --III! -- an automatic release action to complete L sung the brakes on to be set. Arrives by brief closing of the switching contact --III/1 -- a short current pulse to the control inlet --G-- the Thyristets --Th--, by it of anode --A-- to the cathode --K-- and thus the coil becomes leading --SP2-- the electro-pneumatic release valve --2-- excited. There the thyristor --Th-- also after opening the switching contact --llI/1 -- remains leading - in it exists the straight automatic release action -, if the full load current of anode --A-- to cathode --K-- the thyristor --Th-- not under a certain holding current value, becomes the automatic release action falls only by Instellungbringen of the Weehsclschalters --I-- into the brake position terminates, there in the brake position D s of change over switch --I-- over its second switching contact --I/2 -- at the anode --A-- the thyristor --Th-- the same potential as at its cathode --K-- lies close, so that the full load current by the thyristor --Th-- on zero and thus under its holding current value falls. Closing the switching contact --II/1 -- the release Rome circle is not influence on the situation “release” automatically to have. Therefore are in series with the switching contact --II/1 -- and parallel to the anode --A-- and cathode --K-- the Thyrtstors --Th-- two diodes switched into series --D-- angordnet, at those the voltage drop is larger than between anode --A-- and cathode --K-- the leading thyristor --Th--. Thus flows also with locking of the switching contacts --II/1 -- a full load current over the thyristor --Th--, so that this and is not interrupted the automatic release action remains leading. Without the diodes --D-- became with locking of the switching contact --II/1 -- the release Rome circle during the automatic release action at the anode --A-- and the cathode --K-- the thyristor --Th-- the same tension lie close and so the thyristor --Th-- it closes whereby the automatic release action would be terminated. The remark example shown in Fig.3 differs from in Fig.2 by the replacement of the two diodes --D-- by a Ohm's resistance --R--. The value the honour ashes of the resistance --R-- it is so large with the fact that with closed switching contact --II/1 -- the release Rome circle the voltage drop at it is larger than the leading Thyristore --Th--. The advantage of the remark example with the diodes, shown in Fig.2 --D-- it lies in the fact that the voltage drop at the diodes --D-- always nearly approximately directly is independent, of the height of the supply voltage of the entire circuit, during for another supply voltage and thus another current flow over the Ohm's resistance --R-- with closed switching contact --II/1 -- generally also another Ohm's resistance --R-- to be used must.