EP0074581A1 - Device for regulating a hub or an angular displacement independently of the load and proportionally to an input signal - Google Patents

Device for regulating a hub or an angular displacement independently of the load and proportionally to an input signal Download PDF

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Publication number
EP0074581A1
EP0074581A1 EP82108132A EP82108132A EP0074581A1 EP 0074581 A1 EP0074581 A1 EP 0074581A1 EP 82108132 A EP82108132 A EP 82108132A EP 82108132 A EP82108132 A EP 82108132A EP 0074581 A1 EP0074581 A1 EP 0074581A1
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EP
European Patent Office
Prior art keywords
control
piston
actuator
main control
pilot
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP82108132A
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German (de)
French (fr)
Inventor
Wolfgang Prof. Dr.-Ing. Backé
Original Assignee
Wolfgang Prof. Dr.-Ing. Backé
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Priority to DE3135855 priority Critical
Priority to DE3135855A priority patent/DE3135855A1/en
Application filed by Wolfgang Prof. Dr.-Ing. Backé filed Critical Wolfgang Prof. Dr.-Ing. Backé
Publication of EP0074581A1 publication Critical patent/EP0074581A1/en
Withdrawn legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B9/00Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member
    • F15B9/02Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type
    • F15B9/08Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor
    • F15B9/09Servomotors with follow-up action, e.g. obtained by feed-back control, i.e. in which the position of the actuated member conforms with that of the controlling member with servomotors of the reciprocatable or oscillatable type controlled by valves affecting the fluid feed or the fluid outlet of the servomotor with electrical control means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F15B13/043Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves
    • F15B13/0435Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with electrically-controlled pilot valves the pilot valves being sliding valves

Abstract

The device has an actuator (3) in the form of a slide or piston and a force feedback (29, 30) provided between the actuator (3) and the control valve. The control valve is designed in two stages and has a main control stage (9) in the form of a piston with at least one control surface and a pilot stage (10) centrally located therein in the form of a pilot piston, the pilot stage (10) and main control stage (9) being in a follow-up control loop. The control side (18) of the piston of the main control stage (9) is coupled to a connecting line in which there are two resistors, at least one of which can be controlled by the pilot piston. Furthermore, the control side (6) of the actuator (3) is provided with a further connecting line, in which there is at least one control cross section (16) of the piston of the main control stage (9), while the other side of the actuator is directly or indirectly connected to the inlet (31) connected is. Finally, a force feedback (30) is provided between the actuator (3) and pilot piston (9), and a restoring force (29) acts on the main control piston

Description

  • The invention relates to a device for load-independent, an input signal proportional stroke and angle control with a housing, an oil inlet and an oil outlet and an actuator in the form of a piston or slide, which is in a control circuit with a pressure-balanced control valve cooperating with a control device, wherein A force feedback is arranged between the actuator and the control valve.
  • Such a device is already known, in which a piston slide controls a connection between an inlet, two consumers and a return via four control edges. A control valve piston acts on this piston slide via a spring force feedback, the other side of which is acted upon by a magnetically actuated tappet of an electrically controlled control device.
  • Devices of this type have disadvantages in their stationary behavior, particularly in the case of larger dimensions. The actuator does not respond sufficiently quickly and with the desired stability to setpoint changes. Other disadvantages are the susceptibility to flow forces, the sensitivity to contamination and the high manufacturing requirements.
  • The object of the present invention is to eliminate, in particular, the disadvantages and shortcomings indicated above in a device of the type mentioned at the outset.
  • This object is achieved according to the invention in a device of the type mentioned at the outset in that the control valve is of two stages and has a main control stage in the form of a piston with at least one control surface and a pilot stage arranged centrally therein in the form of a pilot piston, the pilot stage and main control stage in a follow-up control loop lie that the control side of the piston of the main control stage is coupled to a connecting line in which Resistors are located, of which at least one can be controlled by the pilot piston, that the control side of the actuator is provided with a further connecting line in which there is at least one control cross section of the piston of the main control stage, while the other side of the actuator is connected directly or indirectly to the inlet that a force feedback is provided between the actuator and pilot piston and that a restoring force acts on the main control piston.
  • According to a further proposal of the invention, the device can be designed such that an electrical feedback of the variable to be controlled is provided to the electrical input signal of the control device. In addition to the force feedback, this also results in a corrective action, which leads to an exact adherence to the setpoint value, which is particularly important with smaller setpoint values.
  • According to a further proposal of the invention, the device can be designed so that the piston of the main control stage is designed as a differential piston.
  • According to a further proposal of the invention, the device can be designed such that a fixed orifice is connected upstream of the control side in the connecting line to the control side of the piston of the main control stage.
  • According to a further proposal of the invention, the device can be designed so that the actuator is designed as a differential piston.
  • According to a further proposal of the invention, the device can be designed such that the actuator is supported on the housing via a spring.
  • According to a further proposal of the invention, the device can be designed such that the force feedback between the actuator and the pilot piston is formed by a feedback spring provided directly between these components.
  • According to a further proposal of the invention, the device can be designed so that the force feedback spring is a compression spring and the control device converts the input signal into a compression force.
  • According to a further proposal of the invention, the device can be designed so that the return spring is a tension spring and the control device converts the input signal into a tension force. This arrangement enables position control even with large strokes of the actuator, since a tension spring cannot buckle.
  • According to a further proposal of the invention, the device can be designed such that the return spring is a spiral spring.
  • Such an embodiment is particularly useful when the device is intended for angle control.
  • According to a further proposal of the invention, the device can be designed such that a spring supported on the actuator acts on the main control piston. This spring is used to return the main spool to its original position.
  • According to a further proposal of the invention, the device can be designed such that a spring supported on the housing acts on the main control piston. This spring also serves the purpose of returning the main control piston to its starting position.
  • According to a further proposal of the invention, the device can be designed so that both ends of the main and pilot pistons communicate with a control side of the actuator directly or via a damping orifice. This results in pressure equalization for main and pilot spool.
  • According to a further proposal of the invention, the device can be designed such that there are two control cross sections of the piston of the main control stage in the connecting line on the control side of the actuator, which control a connection to the inlet or outlet. This design enables a higher adjustment speed of the actuator.
  • According to a further proposal of the invention, the device can be designed such that the control side of the actuator is connected to the inlet via a fixed panel.
  • According to a further proposal of the invention, the device can be designed such that the main control piston has two further control cross sections which control a connection between the side of the actuator opposite the control side on the one hand and the inlet and outlet on the other.
  • According to a further proposal of the invention, the device can be designed such that the actuator is designed as a rotary cylinder piston with two control spaces.
  • According to a further proposal of the invention, the device can be designed such that the control chambers of the rotary piston are controlled by at least one control cross section of the main control piston.
  • According to a further proposal of the invention, the device can be designed so that each control chamber of the rotary piston is assigned a control valve with a control device.
  • According to a further proposal of the invention, the device can be designed such that the actuator consists of two coupled rotary cylinders with unequal piston surfaces, a small surface with the supply pressure and that surface in the other rotary cylinder against overlying large area is connected to at least one control cross section of the main control piston, while the other two rooms of the rotary cylinder are connected to the drain.
  • According to a further proposal of the invention, the device can be designed such that the actuator is designed as a symmetrically designed control slide, which is supported at both ends by a spring on the housing and cooperates with a control device and a control valve.
  • According to a further proposal of the invention, the device can be designed such that the end faces of the main control piston are of different sizes to generate the restoring force of this piston.
  • In such an embodiment, the use of springs to generate the restoring force can be dispensed with. This means that the follow-up control of the main spool is still functional even at very low system pressure.
  • According to a further proposal of the invention, the device can be designed so that the actuator is designed as a built-in valve piston of a proportional throttle valve.
  • According to a further proposal of the invention, the device can be designed such that a volume flow sensor is connected downstream of the actuator and the force feedback is formed by a return spring arranged between the sensor and pilot piston. The actuator is also stroke-controlled here 1, which is converted into a force of the return spring by changing the position of the sensor.
  • According to a further proposal of the invention, the device can be designed such that the actuator is a variable displacement pump controlled by the main control piston.
  • Finally, according to a further proposal of the invention, the device can be designed such that the actuator is a slide valve piston.
  • In the following part of the description, some embodiments of the subject matter of the invention are described with reference to drawings. It shows:
    • 1 shows an axial section through a first embodiment of the device according to the invention, the actuator being designed as a linear cylinder and both stages of the control valve each having a control edge,
    • 2 shows an axial section similar to FIG. 1 through a further embodiment, the pilot piston having one control edge and the main control piston having two control edges,
    • 3 shows an axial section through an embodiment largely similar to FIG. 2, in which the actuator is supported on the pilot piston, on the main control piston and on the housing via a helical spring,
    • 4 shows an axial section similar to FIGS. 2 and 3 through a further embodiment of the device according to the invention, in which the main control piston is supported on the housing via a plate spring,
    • 5 shows an axial section through a further embodiment of the subject matter of the invention, a coil spring being arranged between the main control piston and the control device fastened to the housing,
    • 6 shows an axial section through a further embodiment, the pilot piston having one control edge and the main control piston having four control edges for controlling the spaces on both sides of the actuator piston,
    • 7 shows an axial section through a further embodiment, in which no return spring acts on the main control piston,
    • 8 shows an axial section through a further embodiment of the subject matter of the invention, the force feedback between the actuator and pilot piston being effected by a tension spring,
    • 9 shows a section through a further embodiment of the subject matter of the invention, the actuator being designed as a rotary piston and the main control piston having four control edges,
    • 10 shows a section through an embodiment of the subject matter of the invention similar to FIG. 9, a rotary cylinder with two piston surfaces of different sizes being axially offset relative to one another being used,
    • 11 shows a section through a further embodiment of the device according to the invention, the actuator being designed as a rotary cylinder and both control spaces being controlled by two symmetrically arranged control valves,
    • 12 shows an axial section through a further embodiment of the subject matter of the invention, the actuator being designed as a built-in valve piston,
    • 13 shows an axial section through a further embodiment of the subject matter of the invention, in which the actuator is designed as a variable displacement pump with a downstream volume flow sensor in the form of a built-in valve piston,
    • 14 shows an axial section through a further embodiment of the subject matter of the invention, in which the actuator is designed as a built-in valve piston with a downstream volume flow sensor,
    • 15 shows an axial section through a further embodiment of the subject matter of the invention, in which the actuator is designed as a symmetrical piston slide, which is centered by springs and cooperates with a control valve on both sides, and
    • 16 shows a signal flow diagram with an electrical feedback of the variable to be controlled.
  • 1 has a two-part housing 1, which in its part 2 has a bore for a differential piston 3 serving as an actuator. This differential piston 3 has a piston rod 4 which protrudes from section 2 and can be connected to any actuator. The control chamber 6 lies on the larger piston surface 5 of the differential piston 3. The smaller surface 7 of the differential piston 3 is referred to as the rear of the actuator.
  • In the second part 8 of the housing 1 is the control valve, which consists of a main control piston 9 and a pilot piston 10. On one side, the end face of the main control piston 9 and the pilot piston 10 lies directly on the control chamber 6, so that these end faces are acted upon by the pressure prevailing in the control chamber 6. A line 11 connects the control chamber 6 with the chamber 12 facing the opposite end faces of the main control piston 9 and pilot piston 10, so that the pressure of the control chamber 6 is present on all end faces of the two pistons.
  • The pilot piston 10 has a control edge 13, which controls a passage 14 into an outer annular groove 15 of the main control piston 9. This annular groove 15 is in turn delimited by a control edge 16 which controls a passage cross section to the line 11 and thus to the control chamber 6 of the actuator.
  • The main control piston 9 forms, through a radially outwardly projecting shoulder 17, a control chamber 18 which communicates via a bore 19 with an outer annular groove of the pilot piston 10, which can be connected to the outer annular groove 15 of the main control piston 9 via the control edge 13 ".
  • The housing 1 has an inlet 20 which communicates directly with the rear of the differential piston 3. The inlet 20 is also connected to the control side 6 of the differential piston 3 via a line 21 and a fixed orifice 22. Another fixed orifice 23 connects the inlet 20 to the control chamber 18 of the main control piston 9 via the line 21. The external annular groove 15 of the main control piston 9 communicates with a drain 31.
  • A control device 24 is attached to the part 8 of the housing 1 and converts an electrical signal via an electromagnet 25 into a proportional pressure force which acts on the pilot piston 10 via a tappet 26. The control device 24 is equipped in a known manner with an adjusting device 27.
  • At the rear 7 of the differential piston 3 engages a coil spring 28, the other end of which is supported on the housing 1. In the control chamber 6 of the differential piston 3, two coil springs 29, 30 are provided, each of which is supported with one end on the differential piston 3. The other end of the coil spring 29 lies against the end face of the main control piston 9. The spring 30, on the other hand, is supported on the pilot piston 10 and forms a return spring.
  • If an electrical signal is now given to the control device 24, which results in a pressure force on the tappet 26, which leads to a displacement of the pilot piston 10 to the left in FIG. 1, the control edge 13 gives the passage 14 to the annular groove 15 and thus to the outlet 31 free. This means that the pressure in the control chamber 18 of the main control piston 9 drops and that consequently the main control piston 9 tracks the pilot piston 10. This displacement of the main control piston 9 in turn has the consequence that the line 11 via the control edge 16 of this main control piston comes into contact with the annular groove 15 and the outlet 31. The pressure in the control chamber 6 of the differential piston 3 drops. Consequently, the differential piston 3 moves to the right until the force of the return spring 30 corresponds to the force exerted by the plunger 26 of the control device 24.
  • If an interference force now acts on the piston rod 4 ′ of the differential piston 3, this leads to an increase or reduction in the force acting on the pilot piston 10 via the return spring 30. There is then a comparison between this spring force and the pressure force of the plunger 26 which is proportional to the input signal of the control device 24 and which initially results in a displacement of the pilot piston 10 in one direction or the other. The main control piston 9 follows the movement of the pilot piston 10, and its control edge 16 opens or closes the passage cross section to the line 11 in order to bring the differential piston 3 into its position corresponding to the input signal of the control device 24 by changing the pressure in the control chamber 6.
  • The device according to FIG. 2 largely corresponds to that according to FIG. 1. Only the deviations of this embodiment compared to that according to FIG. 1 are described below. For this purpose, it should only be mentioned that the main control piston 9 has two control edges 35, 36, the control edge 35 delimiting an outer annular groove 37 which is connected via a line 38 to the line 21 and the inlet 20. The control edge 36 of the main control piston 9 delimits, as described in connection with FIG. 1, an annular groove 15 which communicates with the outlet 31.
  • In the starting position of the main control piston 9 shown in FIG. 2, the control edges 35, 36 block every connection between the line 11 and the annular grooves 37, 15. However, if the main control piston 9 is moved to the left in FIG. 2, the line 11 and thus the control chamber 6 are connected to the outlet 31 via the annular groove 15. A shift of the main control piston 9 to the right, on the other hand, leads via _ - the control edge 35 to a connection between the inlet 20, the line 21, the line 38, the line 11 and the control chamber 6. This control of the passage cross section by the active control edge 35 leads to Control room 6 takes the place of the fixed panel provided in the embodiment according to FIG. 1.
  • The embodiment according to FIG. 2 works as described in connection with FIG. 1.
  • The embodiment according to FIG. 3 will now be described insofar as it differs from that according to FIG. 2.
  • Such a deviation lies solely in the fact that a further coil spring 40 is arranged in the control chamber 6 in addition to the spring 29 and the return spring 30, which is located at one end on the larger piston surface 5 of the differential piston 3 and at its other end on the housing 1 supports.
  • This device operates as described in connection with the embodiment of FIG. 1.
  • The embodiment according to FIG. 4 is described below insofar as it differs from that according to FIGS. 2 and 3.
  • On the one hand, the return spring 30 acts on the differential piston 3, the other end of which is supported on the pilot piston 10. On the smaller piston surface 7 of the differential piston 3, as in the embodiment according to FIG. 2, a coil spring 28 engages, which is supported on the housing 1. Deviating from the previously described embodiments, no spring is provided, which is one is supported on the main control piston 9 and on the other hand on the differential piston 3. However, in order to be able to exert a corresponding force on the main control piston 9, a disc spring 45 is arranged in its control chamber 18, which is supported on the one hand on the housing and on the other hand on the shoulder 17 of the main control piston 9 and thus exerts a spring force on the main control piston 9.
  • 4 results from the functional description of the embodiment according to FIG. 1.
  • In the embodiment according to FIG. 5, a return spring 30 and a further coil spring 28 work together with the differential piston 3 according to the embodiment according to FIG. 4. The line 11 connected to the control chamber 6 of the differential piston 3 is connected to either the inlet 20 or the outlet 31 via the two control edges 35, 36 of the main control piston 50. The embodiment according to FIG. 5 initially differs from that according to FIG. 4 in that the main control piston 50 has at its end facing the control chamber 6 a radially outwardly projecting collar 51, the shoulder surface 52 of which forms a control chamber 49 with the housing 1. A pilot piston 53 is arranged concentrically in the main control piston 50 and has two control edges 54, 55, each of which controls a passage 56, 57 between an annular groove 58 of the pilot piston 53 and annular grooves 59, 60 of the main control piston 50. The annular groove 59 is connected to the inlet 20 via a line 61, while the annular groove 60 is connected to the outlet 31. A bore 62 connects the control chamber 49 with the annular groove 58 of the pilot piston 52.
  • One end of a spring 63, the other end of which acts on the associated end face of the main control piston 50, is supported on the control device 24, which is firmly connected to the housing 1, and thus virtually on the housing 1 itself.
  • In this device, in which the control chamber 49 cooperates with two active control edges 54, 55 of the pilot piston 53, this takes place Connection between the control chamber 6 of the differential piston 3 with the inlet 20 or the outlet 31 as described in connection with the embodiments according to FIGS. 2 to 4.
  • The embodiment according to FIG. 6 has, in accordance with the embodiment according to FIG. 1, for example, a housing 1, in which a differential piston 3 is arranged, on which a return spring 30 and further springs 28 and 29 in the context of FIG. Attack 1 described way. A control device 24 is also placed on the housing.
  • A variation of the embodiment according to FIG. 6 compared to that according to FIG. 1 essentially consists in the fact that a main control piston 79, which has a control chamber 80, cooperates with a pilot piston 77 having a control edge 78, which has a control chamber 80, as used in connection with FIGS. 1 to 4 has been described. This control chamber 80 is connected to an inlet 82 via a fixed panel 81. It is connected via bores 83 to an annular groove 84 of the pilot piston 77. The control edge 78 of the pilot piston 77 establishes a connection between the annular groove 84 and an outlet 86 via a passage 85 in the main control piston.
  • The pilot piston 77 sits centrally in the main control piston 79, which has four control edges 88, 89, 90 and 91. The control edges 88 and 89 connect a connecting line 92 communicating with the rear side 7 of the differential piston 3 either via a line 93 to the inlet 82 or else directly to the outlet 86. The control chamber 6 of the differential piston 3 is connected via a line 94 and the control edges 90, 91 either connected to the outlet 86 or the inlet 82. The essential difference of these embodiments compared to the previously described embodiments is that both sides of the differential piston 3 are controlled by active control edges of the main control piston 79.
  • The function of this embodiment follows from the description made above for FIG. 1.
  • The embodiment according to FIG. 7 has a housing 98, in the part 99 of which a differential piston 3 is arranged, on which, as was described in connection with FIGS. 4 and 5, a return spring 30 and a coil spring 28 act on the one hand. The housing 98 also has the housing parts 100 and 101, with a control device 24 being attached to the housing part 101.
  • In this embodiment, a pilot piston 102 is provided, which has an annular groove 108 of the pilot piston via two control edges 103, 104 and associated passage openings 105, 106 of a main control piston 107 arranged concentrically with it. connects the main control piston 107 with two annular grooves 109, 110. The annular groove 108 of the pilot piston 102 is otherwise connected via a bore 110 a in the main control piston 107 and via a line 111 with a fixed orifice 112 to a control chamber 113 of the main control piston 107.
  • The main control piston 107 is formed in two parts. Its part 114 has two control edges 115, 116 which connect a line which communicates with the control space 117 of the differential piston either to the inlet 20 or to the outlet 31. The main control piston 107 also has a section 118 which sits in the housing part 101 and is designed as a plunger. It forms the control room 113 already mentioned, the rear side 119 of which is connected to the outlet via a line 120. In the part 118 of the main control piston 107, a slidingly guided transmission piece 121 sits centrally, which transmits the force of the tappet 26 of the control device 24 to the pilot piston 102. -
  • If the pilot piston 102 is moved to the left by the force of the tappet 26 in this device, the control edge 103 of this pilot piston provides a connection between the inlet 20, the passage opening 105, the annular groove 108, the bore 110 a, the line 111 via the Fixed panel 112 to the control room 113 free. This leads to a tracking of the main control piston 107, which is limited by the interaction of the control edge 104 with the passage opening 106. The two control edges 115 and 116 of the main control piston now connect the line communicating with the control chamber 117 of the differential piston either to the inlet or to the outlet.
  • The embodiment according to FIG. 8 largely corresponds to that according to FIG. 4. Only the deviations which are present in comparison with this are to be described below.
  • The differential piston 3 is supported via its smaller surface 7 on a spring 28, the other end of which rests on the housing 1. A return spring 130 is designed as a tension spring and is connected at one end to the differential piston 3 and at the other end to the pilot piston 10. The control device 24 is provided with a pull magnet 131, which converts an electrical signal into a proportional pull force, which acts via a pull element 132 on the end of the pilot piston 10 facing away from the return spring 130.
  • A plate spring 133 is supported on the one hand on the control device 24 firmly connected to the housing 1 and thus also on the housing itself and on the other hand on the end face of the main control piston 9 facing the control device 24.
  • The working of this device results from the functional description of the embodiment according to FIG. 1.
  • The embodiment according to FIG. 9 has a housing 136 with a rotary cylinder 137. A rotary piston 139, which is connected to a shaft 138 and which seals the rotary cylinder, is arranged in this housing. divided into two control rooms 140 and 141, the control room 140 in FIG. 9 lying in front of the rotary piston when the rotary piston 139 moves clockwise.
  • A control formed by a pilot piston 142 and a main control piston 143 is accommodated in the housing 136, the pilot piston 142 lying centrally within the main control piston 143.
  • The pilot piston 142 has a control edge 144 and an annular groove 145. The control edge 144 controls a connection between the annular groove 145 and passage openings 146 of the main control piston 143.
  • The main control piston 143 forms, via a radially outwardly projecting shoulder, flat 147 with the housing 136, a control chamber 148, which is connected to an inlet 151 via a line 149, in which a fixed orifice 150 is arranged. In the control chamber 148 there is a plate spring 152 which is supported on the one hand on the shoulder surface 147 of the main control piston 143 and on the other hand on the housing 136. Furthermore, the control chamber 148 is connected to the annular groove 145 of the pilot piston 142 via bores 153, so that, as already described in connection with other embodiments, the main control piston 143 exactly follows each axial displacement of the pilot piston 142.
  • The main control piston forms four control edges 154, 155, 156, 157. The control edges 154, 155 connect a line 158, which communicates with the control chamber 140 of the rotary piston 139, either to the inlet 151 or to an outlet 159. The control edges 156 and 157, on the other hand, transfer a line 160 communicating with the control room 141 establishes a connection between this control room 141 and the inlet 151 or the outlet 159.
  • The line 160 also brings about a pressure compensation on the two end faces of the pilot piston 142 and the main control piston 143. The pressure present in the control chamber 141 is present on both surfaces.
  • With the shaft 138, the radially inner end 161 of a spiral spring 162 is connected, the radially outer end of which carries a pressure rod 163 which transmits the force of the spring 162 to the pilot piston 142.
  • A control device 24 is attached to the housing 136, as was described, for example, in connection with FIG. 1. Their tappet 26 acts on the end of the pilot piston 142 opposite the pressure rod 163.
  • If, in this device, the pilot piston 142 is moved to the left against the force exerted by the pressure rod 163 in FIG. 9 due to the pressure force transmitted by the stub 26 and proportional to an input signal, the control edge 144 releases the through bores 146 and thus connects via the Bores 153 the control chamber 148 with the drain 159. As a result of the drop in pressure in the control chamber 148, the main control piston 143 follows the pilot piston 142.
  • If the main control piston 143 is consequently also shifted to the left, the control edge 154 opens a passage between the inlet 151 and the line 158 to the control chamber 140. At the same time, the control chamber 141 is connected to the outlet 159 via line 160 and the control edge 156. As a result, the pressure in the control room 141 drops. A rotation of the rotary piston 139 counterclockwise and thus one The result is an increase in the compressive force transmitted from the spiral spring 162 to the pressure rod 163. This pressure force is compared with the pressure force transmitted by the tappet 26 of the control device 24.
  • The embodiment of the invention according to FIG. 10 has a housing 170 in which two rotary cylinders 171 and 172 are arranged coaxially. A rotary piston 173 is located in the rotary cylinder 171, the radius of which is larger than that of the rotary cylinder 172. A rotary piston 174 is seated in the rotary cylinder 172.
  • Both rotary pistons 173, 174 are arranged on a shaft 175 in a rotationally fixed manner, the area of the rotary piston 174 being smaller than that of the rotary piston 173.
  • One end 176 of a spiral spring 177 is fixedly connected to the shaft 175, the other end of which is coupled to a pressure rod 178 which acts on an end face of a pilot piston 179, which is seated centrally in a main control piston 180.
  • The pilot piston 179 has a control edge 181 which controls through openings 182 of the main control piston to an annular groove 183. The pilot piston 179 also has an annular groove 184, which communicates via bores 185 with a control chamber 186, in which a plate spring 187 is arranged, as was described, for example, in connection with FIG. 4.
  • The main control piston 180, which tracks every movement of the pilot piston 179, has two control edges 188 and 189.
  • In this embodiment, an inlet 190 is provided which communicates via a line 191 with the space of the rotary cylinder 172, which lies in front of this rotary piston when the rotary piston 174 moves clockwise. The space arranged behind this rotary piston 174 is over a Line 193 connected to an outlet 194.
  • The control edges 188 and 189 control, via a line 192, a connection of the inlet 190 to the space of the rotary cylinder 171, which lies behind it when the associated rotary piston 173 rotates clockwise. The space of the rotary cylinder 173, which lies on the other side of the rotary piston 173, is in constant communication with the outlet 194 via a line 195.
  • The control edge 189 of the master control cylinder controls a connection between the line 192 and an outlet 196. A line 197 ensures that the same pressures are present on the end faces of the pilot piston 179 and of the master control piston 180.
  • A tappet 26 of a pilot control device 24 acts on the end of the pilot piston 179 opposite the pressure rod 178.
  • The embodiment of the invention according to FIG. 11 has a housing 200, which forms a rotary cylinder with two control spaces 201, 202, which are separated from one another by a rotary piston 203. The rotary piston 203 sits on a shaft 204 to which one end of a coil spring 205 is attached. The other end carries a pressure rod 206, which is arranged between lugs 207 of pilot pistons 208 of two control devices arranged symmetrically to one another. In each of these tax. devices, the pilot piston 208 is centrally located in a main control piston 209. The pilot piston 208 and the main control piston 209 are each, as already described, in a follow-up control loop. The main control piston 209 has two control edges 210 and 211, respectively. A line 212 ensures that pressure equalization exists in the end faces of the pilot piston 208 and the main control piston 209.
  • The device has an inlet 213 communicating with the line 212 and an outlet 214. In the right part of the figure, the control edge 210 of the main control piston 209 controls a connection between the inlet 213, line 215 and line 216, which is connected to the control room 20 2 . On the same side of the figure, the control edge 211 controls a connection between the line 216 and the outlet 214. The control device shown on the left in the figure is constructed accordingly and controls a connection between the control chamber 201 and either the inlet 213 or the outlet 214. Both Control devices are provided with control devices 24 of the type described.
  • In the embodiment of the device according to the invention according to FIG. 12, it is designed as a proportional throttle valve. It has a housing 220 which is formed from the parts 221, 222. A pilot piston 223 and a main control piston 224 are seated in the housing part 222 and, as in the previously described embodiments, are arranged concentrically. Pilot spool 223 and main spool 224 are in a slave control loop and are pressure balanced. The main control piston 224 has two control edges 225, 226, which connect a line 229 to a supply line 228 or an outlet 230 communicating with an inlet 227. The line 229, which ensures the pressure equalization of the two control cylinders, is connected to a control side 231, which is located on one side of an installation valve piston 232. The built-in valve piston is supported by a return spring 233 on the pilot piston 223 and by a further spring 234 on the main control piston 224. The built-in valve piston controls a passage cross-section between the inlet 227 and a connection 235. The inlet is coupled to a control chamber 237 of the main control piston 224 via the line 228 and and a fixed blends 236.
  • As already described, a control device 24 is attached to the housing part 222, the plunger 26 of which transmits a compressive force to the pilot piston 223 which is proportional to the electrical input signal of the control device. If this compressive force is sufficient to displace the pilot piston 223 and, as a result, the main control piston 224 downward in the figure, the control chamber 231 of the built-in valve piston 232 becomes via the line 229 and the control edge 226 connected to the drain 230. This means a decrease in the pressure in the control chamber 231 and consequently a lifting of the built-in valve piston 232. On the other hand, if the pilot piston 232 is deflected upwards by the return spring 233, the control edge 225 controls a connection between the feed line 228 and the line 229 and thus to the control side 231. This then results in a downward movement of the built-in valve piston 232. The position of the built-in valve piston 232 corresponding to the electrical signal applied to the control device 24 results from the comparison between the force on the tappet 26 of the control device and the force of the return spring 233.
  • The embodiment according to FIG. 13 has a two-part housing 240 with the housing parts 241 and 242. A control device 24 of the type described is attached to the housing part 241, the tappet 26 of which acts on a pilot piston 243, which is arranged in a follow-up control loop with a concentrically arranged one Main control piston 244 is located. The control pistons 243 and 244 are located in the housing part 241. The main control piston 244 is supported by a spring 245 on the control device 24 and thus on the housing 240 itself. The main control piston 244 forms a control chamber 246.
  • A volume flow sensor 247 in the manner of a built-in valve piston is arranged in the housing part 242. It is located between an inlet 248 and an outlet 249. The volume flow sensor 247 has a control side 250 on which a return spring 251 supported on the pilot piston 243 and a spring 253 supported on an intermediate ring 252 act. A variable displacement pump ' -254, which is controlled by an actuating cylinder 255, is connected upstream of the inlet 248.
  • The pilot piston 243 has two control edges 256, 257, which connect the control chamber 246 of the main control piston 244 either to an outlet 258 or to the line 259, which communicates with the inlet 248. The control chamber 246 is also pressurized via a line 260 tion device 261 connected.
  • The main control piston 244 has two control edges 262 and 263. A line 264 is also provided which connects the main control piston 244 directly to one side of the actuating cylinder 255 and to the other side 266 of the piston 265 via an orifice 267.
  • If the pressure force corresponding to an electrical input signal on the plunger 26 of the control device 24 leads to a displacement of the pilot piston 243 and as a result thereof to a corresponding displacement of the main control piston 244, the inlet 248 is connected to the line 264 via the line 259 and the control edge 262 , which results in a displacement of the pressure piston 255 in the figure to the left and thus an increase in the delivery flow of the variable displacement pump 254. This delivery flow results in a corresponding stroke of the volume flow sensor 247, which in turn is fed back as a force to the pilot piston 243 via the spring 251 and is thus compared with the pressure force of the control device 24.
  • The embodiment according to FIG. 14 has a two-part housing 280 with the parts 281 and 282. A control device 24 of the type described is attached to the housing part 281. A pilot piston 283 is located in the housing part 281 in a follow-up control loop with a main control piston 284.
  • The housing part 282 has an inlet 285 and an outlet 286. The inlet 285 is followed by an actuator 287 designed as a built-in valve 287, which is followed by a volume flow sensor 288. The built-in valve piston 287 has a control chamber 289 which is connected to the main control piston 284 via a line 290. A line 291 also connects the inlet 285 to the main control piston 284.
  • The volume flow sensor 288 is supported on the pilot piston 283 via a return spring 292, on the main control piston 284 via a further spring 293 and on the housing via a third spring 294.
  • The main control piston 284 has two control edges 295,296. The control edge 295 controls a connection between the inlet 285, the line 291 and the line 290 connected to the control chamber 289. The control edge 296, on the other hand, connects the control chamber 289 via line 290 to an outlet 297. The pressure in the control chamber corresponds to the volume flow sensor 288 the pressure at the outlet 286, since this is connected via a line 298 to the control side of the volume flow sensor.
  • This embodiment, which represents a current regulator of large nominal size, works as follows: If the pressure force on the tappet 26 of the control device 24, which is proportional to an electrical input signal, is sufficient to move the pilot piston 283 and thus also the main control piston 284 downward, the control chamber 289 becomes also via the line 290 associated with drain 297. The pressure in the control room drops and the built-in valve piston 287 releases an inlet cross section. The resulting volume flow in turn results in a stroke of the volume flow sensor 288, which is returned as a force to the pilot piston 283 via the return spring 292 and is compared with the force of the tappet 26.
  • Fig. 15 shows an embodiment of the invention which serves as a proportional directional valve spool. This embodiment is provided with two control devices 24 and two pilot controls, each of which corresponds to the embodiment according to FIG. 3. Only in place of the differential piston 3 is a valve slide 300 arranged here, which has four control edges 301, 302, 303, 304. This embodiment is particularly suitable for large valve designs.
  • 16 is only intended to show schematically that, in addition to the force feedback described, an electrical feedback can also be provided, with which the variable to be controlled is given to the electrical input signal of the control device 24. The difference that is added to the setpoint is formed between the setpoint of the electrical signal and the variable to be controlled. As a result, the force of the plunger 26 of the control device 24 described is increased or decreased in accordance with the control deviation, so that the target value is maintained with greater accuracy.

Claims (26)

1.Device for load-independent, an input signal proportional stroke and angle control with a housing, an oil inlet and an oil outlet and an actuator in the form of a piston or slide, which is in a control circuit with a pressure-compensated control valve cooperating with a control device, between actuator and Control valve a force feedback is arranged, characterized in that the control valve is designed in two stages and has a main control stage in the form of a piston with at least one control surface and a centrally located pilot stage in the form of a pilot piston, the pilot stage and main control stage being in a follow-up control loop that the control side the piston of the main control stage is coupled to a connecting line in which two resistors lie, at least one of which can be controlled by the pilot piston, that the control side of the actuator is connected to a further connection ungsleitung is provided in which at least one control cross section of the piston of the main control stage ', while the other side of the actuator is directly or indirectly connected to the inlet, that a force feedback is provided between the actuator and pilot piston and that a restoring force acts on the main control piston.
2. Device according to claim 1, characterized in that an electrical feedback of the variable to be controlled to the electrical input signal of the control device is provided (Fig. 16).
3. Device according to claim 1 or 2, characterized in that the piston (9; 50; 79; 107; 143; 180; 209; 224; 244; 284) of the main control stage is designed as a differential piston (Fig. 1 to 15).
4. Device according to one of the preceding claims, characterized in that in the connecting line to the control side (18; 80; 148; 186; 237) of the piston (9; 79; 143; 180; 209; 224; 284) of the main control stage a fixed orifice ( 23; 81; 150; 236) is connected upstream of the control side (FIGS. 1 to 4, 6, 8 to 12, 14, 15). -
5. Device according to one of the preceding claims, characterized in that the actuator (3) is designed as a differential piston (Fig. 1 to 8).
6. The device according to claim 5, characterized in that the actuator (3) via a spring (28; 40) on the housing (1; 98) is supported (Fig. 1 to 7).
7. Device according to one of the preceding claims, characterized in that the force feedback between the actuator (3; 139; 173,174; 203; 232; 300) and pilot piston (10; 53; 77; 102; 142; 179; 208; 223) by a return spring (30; 130; 162; 177; 205; 233) provided directly between these components is formed (FIGS. 1 to 12, 15).
8. The device according to claim 7, characterized in that the return spring (30; 233) is a compression spring and the control device (24) converts the input signal into a compressive force (Fig. 1 to 7, 12, 15).
9. The device according to claim 7, characterized in that the return spring (130) is a tension spring and the control device (24) converts the input signal into a tensile force (Fig. 8).
10. The device according to claim 7, characterized in that the return spring (162; 177; 205) is a spiral spring (Fig. 9 to 11).
11. Device according to one of the preceding claims, characterized in that on the main control piston (9; 79; 224) engages on the actuator (3; 232) supporting spring (29; 234) (Fig. 1,2,3,6, 12, 15).
12. Device according to one of claims 1 to 10, characterized in that on the main control piston (9; 50; 143; 180; 209) a spring (45; 63; 133; 152; 187) supported on the housing (1; 136) attacks (Fig. 4,5,8 to 11).
13. Device according to one of the preceding claims, characterized in that both ends of the main and pilot piston communicate with a control side (6; 117; 231; 252) of the actuator directly or via a damping diaphragm (Fig. 1 to 12.15).
14. Device according to one of the preceding claims, characterized in that in the connecting line of the control side of the actuator (3; 139; 174; 203; 232; 254; 237) two control cross sections (35,36; 90,91; 115,116; 154,155,156,157; 188,189; 210,211; 225,226; 262, 263; 295,296) of the piston (9; 50; 79; 107; 143; 180; 209; 224; 244; 284) of the main control stage, which control a connection to the inlet or outlet (Fig . 2 to 15).
15. The device according to one of claims 1 to 13, characterized in that the control side (6) of the actuator (3) via a fixed panel (22) with the inlet (20) is in communication (Fig. L).
16. The device according to one of the preceding claims, characterized in that the main control piston (79; 143) has two further control cross sections (88.89; 154.155, 156, 157) which have a connection between the side of the control side (6; 140, 141) (7) of the Control the actuator (3; 139) on the one hand and the inlet (82; 151) and the outlet (86; 159) on the other hand (Fig. 6,9).
17. The device according to one of claims 1 to 4,9, 13 to 16, characterized in that the actuator (139; 173; 203) is designed as a rotary cylinder piston with two control spaces.
18. The apparatus according to claim 17, characterized in that the thrust spaces of the rotary piston are controlled by at least one control cross section of the main control piston.
19. The apparatus according to claim 17, characterized in that each control chamber (201, 202) of the rotary piston (203) is assigned a control valve with a control device (24) (Fig. 11).
20. Device according to one of claims 1 to 4, 10, 13 to 16, characterized in that the actuator consists of two coupled rotary cylinders with unequal piston surfaces, with a small surface with the supply pressure and the large surface opposite this surface in the other rotary cylinder with at least one control cross section of the main control piston (180) is connected, while the other two spaces of the rotary cylinder are connected to the outlet (194) (FIG. 10).
21. Device according to one of claims 1 to 4,7,8,11 to 16, characterized in that the actuator is designed as a symmetrically formed control slide (208; 300) which is supported at both ends by a spring on the housing and cooperates with a control device (24) and a control valve (Fig. 11, 15).
22. Device according to one of claims 1 to 10 and 13 to 21, characterized in that the end faces of the main control piston (107) for generating the restoring force of this piston (118) are of different sizes (Fig. 7).
23. Device according to one of claims 1 to 4, 7 to 9, 11 to 16, characterized in that the actuator is designed as a built-in valve piston (232) of a proportional throttle valve (Fig. 12).
24. The device according to one of claims 1 to 4, characterized in that the actuator (244; 287) is followed by a volume flow sensor (247; 288) and the force feedback through a return spring (253; 283) arranged between the sensor and pilot piston (243; 283). 292) is formed (Fig. 13, 14).
25. The device according to claim 24, characterized in that the actuator is a variable displacement pump (254) controlled by the main control piston (244) (Fig. 13).
26. The apparatus according to claim 24, characterized in that the actuator is a slide valve piston (287) (Fig. 14).
EP82108132A 1981-09-10 1982-09-03 Device for regulating a hub or an angular displacement independently of the load and proportionally to an input signal Withdrawn EP0074581A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE3135855 1981-09-10
DE3135855A DE3135855A1 (en) 1981-09-10 1981-09-10 Device for load-independent lift and angle control proportional input signal

Publications (1)

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EP82108132A Withdrawn EP0074581A1 (en) 1981-09-10 1982-09-03 Device for regulating a hub or an angular displacement independently of the load and proportionally to an input signal

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GB2141262A (en) * 1983-06-08 1984-12-12 Dowty Hydraulic Units Ltd Servo valve
DE3428708A1 (en) * 1984-08-03 1986-02-13 Rexroth Mannesmann Gmbh Device for the adjustment, proportional to an electrical input signal and independent of the load, of a control valve for a control mechanism
US5248642A (en) * 1992-05-01 1993-09-28 W. R. Grace & Co.-Conn. Catalytic cracking catalysts and additives
DE4236505A1 (en) * 1992-10-29 1994-05-05 Teves Gmbh Alfred Valve block for slip-regulated vehicle braking system - with additional brake pressure regulator for rear brakes with pressure reduction valve and electromagnetic blocking device
US5366202A (en) * 1993-07-06 1994-11-22 Caterpillar Inc. Displacement controlled hydraulic proportional valve
CH710237A1 (en) * 2014-10-15 2016-04-15 Liebherr Machines Bulle Sa Self-regulating servovalve.

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DE3402352A1 (en) * 1984-01-24 1985-07-25 Rexroth Mannesmann Gmbh Method and device for electro-hydraulic pressure adjustment
DE102012106626B3 (en) 2012-07-20 2013-09-26 Krauss-Maffei Wegmann Gmbh & Co. Kg Weapon platform, military vehicle with a weapons platform and method of operating a weapons platform

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2141262A (en) * 1983-06-08 1984-12-12 Dowty Hydraulic Units Ltd Servo valve
DE3428708A1 (en) * 1984-08-03 1986-02-13 Rexroth Mannesmann Gmbh Device for the adjustment, proportional to an electrical input signal and independent of the load, of a control valve for a control mechanism
US5248642A (en) * 1992-05-01 1993-09-28 W. R. Grace & Co.-Conn. Catalytic cracking catalysts and additives
DE4236505A1 (en) * 1992-10-29 1994-05-05 Teves Gmbh Alfred Valve block for slip-regulated vehicle braking system - with additional brake pressure regulator for rear brakes with pressure reduction valve and electromagnetic blocking device
US5366202A (en) * 1993-07-06 1994-11-22 Caterpillar Inc. Displacement controlled hydraulic proportional valve
CH710237A1 (en) * 2014-10-15 2016-04-15 Liebherr Machines Bulle Sa Self-regulating servovalve.

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