EP0057526A2 - Hydraulische Wahlschaltung mit Stromsteuerung - Google Patents

Hydraulische Wahlschaltung mit Stromsteuerung Download PDF

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Publication number
EP0057526A2
EP0057526A2 EP82300228A EP82300228A EP0057526A2 EP 0057526 A2 EP0057526 A2 EP 0057526A2 EP 82300228 A EP82300228 A EP 82300228A EP 82300228 A EP82300228 A EP 82300228A EP 0057526 A2 EP0057526 A2 EP 0057526A2
Authority
EP
European Patent Office
Prior art keywords
line
actuator
hydraulic
valve
flow
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Withdrawn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
EP82300228A
Other languages
English (en)
French (fr)
Other versions
EP0057526A3 (de
Inventor
Willard Lyle Chichester
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Doosan Bobcat North America Inc
Original Assignee
Clark Equipment Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Clark Equipment Co filed Critical Clark Equipment Co
Publication of EP0057526A2 publication Critical patent/EP0057526A2/de
Publication of EP0057526A3 publication Critical patent/EP0057526A3/de
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/05—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed specially adapted to maintain constant speed, e.g. pressure-compensated, load-responsive
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/20—Means for actuating or controlling masts, platforms, or forks
    • B66F9/22—Hydraulic devices or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/3059—Assemblies of multiple valves having multiple valves for multiple output members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40507—Flow control characterised by the type of flow control means or valve with constant throttles or orifices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40515—Flow control characterised by the type of flow control means or valve with variable throttles or orifices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41527—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41527—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve
    • F15B2211/41536—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve being connected to multiple ports of an output member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/45—Control of bleed-off flow, e.g. control of bypass flow to the return line
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
    • F15B2211/50518—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using pressure relief valves
    • F15B2211/50527—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using pressure relief valves using cross-pressure relief valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5153—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve
    • F15B2211/5154—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve being connected to multiple ports of an output member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/52—Pressure control characterised by the type of actuation
    • F15B2211/528—Pressure control characterised by the type of actuation actuated by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7053—Double-acting output members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/78—Control of multiple output members

Definitions

  • This invention relates to a hydraulic circuit selector with flow control.
  • each actuator is connected to the main pressure and return lines by a hydraulic circuit selector which is operator controlled and determines which of the hydraulic actuators will be supplied with pressurized hydraulic fluid.
  • the main lines transfer fluid to and from the circuit selector, and individual hydraulic line pairs connect each of the actuators to the circuit selector.
  • One of the principal objects of the present invention is to provide a hydraulic circuit selector having an automatic flow control which permits selectively operating one of a plurality of hydraulic actuators having different fluid flow requirements from a single pair of pressure and return lines connected to a hydraulic pump, and which automatically bypasses the excess fluid flow to the fluid reservoir when an actuator having a lesser fluid flow requirement than the flow supplied from the pump is being operated.
  • Another object of the present invention is to provide a hydraulic circuit selector with flow control which can be adjusted to provide the required fluid flo.
  • a hydraulic circuit selector with flow control which can be adjusted to provide the required fluid flo.
  • various types of hydraulic actuators and which requires only a single pair of lines to the circuit selector valve, each of which may operate as a fluid pressure line or as a fluid return line, with the bypassed fluid flowing from a flow control valve in the line operating as a pressure line to the line of the pair functioning as a return line.
  • the present invention provides a hydraulic circuit selector with an automatic flow control to bypass the excess fluid flow to the fluid reservoir when operating hydraulic actuators requiring a lesser fluid flow than the maximum supplied from a source.
  • Two operator controlled valves are provided in a hydraulic system embodying the present invention, the first valve being for selecting the direction of operation of the hydraulic actuators, and the second valve being a circuit selector valve for determining which of a plurality of actuators is operated.
  • a connection is provided between the hydraulic pump and an actuator requiring the maximum flow rate.
  • An actuator requiring less than the maximum flow supplied from the pump is connected to the pump through a bypass type flow control valve, two of which are provided if the actuator is double acting.
  • the flow control valve includes an orifice and a bypass valve responsive to a minimal pressure drop across the orifice.
  • the bypass valve opens when the required pressure drop is detected, and the excess fluid flow over that required to operate the actuator is bypassed from the upstream side of the orifice to the fluid return line.
  • the orifice in each of the bypass type flow controls may be of the variable tuning type, so that the present hydraulic circuit selector with flow control can be used for various devices, and the orifice can be tuned for the flow requirements of the hydraulic actuators on the device.
  • numeral 10 designates a hydraulic circuit having the automatic flow control feature embodying the present invention, for selectively operating one hydraulic actuator of a plurality of actuators, and for bypassing the excess fluid to the reservoir when an actuator requiring less than the maximum fluid flow is being operated.
  • Circuit 10 includes a hydraulic pump 12 and an operator controlled auxiliary valve assembly, indicated in the drawing by the box designated by numeral 14, which, on a fork lift truck, for example, normally will be on the body of the truck.
  • Hydraulic lines 16 and 18 connect the auxiliary valve to a circuit selector assembly, represented by the box designated by the numeral 20 in the drawing.
  • the circuit selector is connected to, for the selective operation of, hydraulic actuators 22 and 24, which may be hydraullc motors, hydraulic piston-and-cylinder assemblies or other hydraulic devices.
  • Auxiliary valve assembly 14 includes a valve means 26 having a neutral section 28 and fluid communicating sections 30 and 32 which are selected for the desired direction of operation for actuators 22 and 24.
  • Pump 12 pumps fluid from a reservoir or sump 34 through a pressure line 36 to valve 26.
  • valve 26 When valve 26 is in the neutral position the fluid pumped by pump 12 flows through the neutral section to a return line 38 and back to sump 34.
  • the fluid communicating sections 30 and 32 operate to transfer the fluid through the valve so that in one of the positions, i.e., that designated by numeral 30 in the figure, hydraulic line 16 operates as the pressure line to the circuit selector assembly, and hydraulic line 18 operates as a return line from the assembly.
  • hydraulic line 18 operates as a pressure line to the circuit selector assembly, and hydraulic line 16 as a return line from the assembly.
  • a pressure control valve 40 is disposed between hydraulic line 36 and return lines 42 and 38 and is connected to line 36 by line 43 for sensing the pressure in line 36 and thus operating the valve to maintain a preselected fluid pressure in line 36 to valve means 26.
  • Circuit selector assembly 20 includes a circuit valve 50 for selectively operating either of actuators 22 or 24, and flow control valves 52 and 54 for bypassing the excess fluid to sump 34 when operating actuator 24.
  • Circuit valve 50 has two operating positions wherein hydraulic fluid may flow therethrough to the hydraulic actuators. The positions are shown in the drawing as sections 56 and 58, one of which is in flow communication with hydraulic lines 16 and 18 when either actuator is operated. Section 58 connects hydraulic lines 16 and 18 to hydraulic lines 60 and 62 for direct flow communication with actuator 22, which, for purposes of illustration, operates at the maximum flow from valve assembly 14. Operation of actuator 22 in either direction as selected by valve 26 will occur at substantially the same pressure and displacement as that supplied from line 36, in that no flow restriction is interposed between line 36 and actuator 22.
  • Section 56 connects hydraulic lines 16 and 18 to hydraulic lines 64 and 66, and places actuator 24 in flow communication with valve assembly 14.
  • the hydraulic fluid passes through one or the other of flow control valves 52 and 54 when actuator 24 is operated, and the excess fluid beyond that flow required to operate actuator 24 is bypassed back to sump 34.
  • Hydraulic line 64 is connected to one side of actuator 24 and is connected by section 56 of circuit valve 50 to hydraulic line 16.
  • Flow control valve 52 is disposed in line 64 between circuit valve 50 and actuator 24 for reducing the flow of fluid to actuator 24 when line 64 is the pressure line.
  • Hydraulic line 66 is connected to the other side of actuator 24, and is connected by section 58 of circuit valve 50 to hydraulic line 18.
  • Flow control valve 54 is disposed in line 64 between circuit valve 50 and actuator 24 for reducing the fluid flow to actuator 24 when line 66 is the pressure line.
  • One or the other of the flow control valves operates whenever fluid flows to actuator 24, depending upon the direction in which the actuator is being operated and which of the lines 64 or 66 is the pressure line, as controlled by valve 26.
  • Flow control valve 52 includes a tuning orifice 80 which may be tuned to the flow requirements of actuator 24.
  • a hydraulic line 82 connects hydraulic line 64 anterior to orifice 80 to a relief valve 84 which in turn is connected to hydraulic line 66 by line 85.
  • the relief valve 84 is responsive to a pressure drop across orifice 80, sensed through pilot lines 86 and 88 connecting, respectively, relief valve 84 with hydraulic line 82 and relief valve 84 with hydraulic line 64 downstream from orifice 80.
  • a pressure drop across orifice 80 as determined by the size of the orifice and the force of a calibrated spring 89, opens relief valve 84, and the excess fluid not required for operation of actuator 24 passes through valve 84 and hydraulic line 85 to hydraulic line 66.
  • the pressure drop across the orifice sufficient to open the relief valve can be relatively small, such as a 3.53kg/cm 2 (50 P S I ) drop.
  • Flow control valve 54 is similar to valve 52, and includes a tuning orifice 90 which may be tuned to the flow requirements of actuator 24.
  • a hydraulic line 92 connects hydraulic line 66 anterior to orifice 90 to a relief valve 94 which in turn is connected to hydraulic line 64 by line 95.
  • Relief valve 94 is responsive to a pressure drop across orifice 90, sensed through pilot lines 96 and 98 connecting, respectively, relief valve 94 with hydraulic line 92, and relief valve 94 with hydraulic line 66 downstream from orifice 90.
  • a pressure drop across orifice 90 as determined by the size of the orifice and the force of a calibrated spring 99, opens relief valve 94, and the excess fluid not required for operation of actuator 24 passes through valve 94 and hydraulic line 95 to hydraulic line 64.
  • circuit valve 50 is operated to place hydraulic lines 16 and 18 in flow communication with hydraulic lines 60 and 62 through valve section 58. If valve 26 is in the neutral position, hydraulic fluid from pump 12 circulates freely back to sump 34 through return line 38. If section 30 of valve 26 connects the various hydraulic lines, line 16 functions as a pressure line, line 18 functions as a return line and actuator 22 will operate to move the piston in the actuator to the left as shown in the drawing. If section 32 is used to connect the hydraulic lines, line 18 functions as the pressure line, and line 16 functions as the return line, so that actuator 22 will sequence to the right.
  • the fluid supplied from pump 12 to actuator 22 will be at substantially the same pressure as it is when it is in line 36 coming from the pump, the pressure being determined by the setting selected for control valve 40 by a calibrated spring therein opposing the fluid pressure transmitted through line 43.
  • actuator 24 operates by a fluid flow less than the flow supplied from pump 12.
  • Tuning orifices 80 and 90 are adjusted to restrict the fluid flow to meet the requirements of actuator 24.
  • circuit valve 50 is operated to place section 56 in communication with lines 16 and 18, thereby connecting lines 16 and 18 with lines 64 and 66. If valve 26 is in a position so that line 16 is a pressure line and line 18 a return line, the hydraulic fluid will flow through line 64 and flow control valve 52 to actuator 24.
  • the pressure drop across the orifice is detected by relief valve 84, and the relief valve will open to bypass the excess fluid not required for the operation of actuator 24, through hydraulic lines 82 and 85 to line 66 and return line 18 to sump 34.
  • valve 26 If valve 26 is in a position so that line 18 is a pressure line and line 16 is a return line, the hydraulic fluid will flow through line 66 and flow control valve 54 to actuator 24, and the actuator will operate in the opposite direction from that just described. As the fluid flows through orifice 90, the pressure drop across the orifice is detected by relief valve 94, and the relief valve will open and bypass the excess fluid not required for operation of actuator 24 through hydraulic lines 92 and 95 to line 64 and return line 16 to sump 34.
  • Orifices 80 and 90 being tuning orifices, permit the flow control valves to be tuned for the flow requirements of the actuator being operated, and the valves can be adjusted for use with different attachments.
  • Relief valves 84 and 94 respond to a predetermined pressure drop across the orifices to bypass the excess fluid flow to sump.
  • the present hydraulic circuit selector with automatic flow control can be used whenever a plurality of actuators are selectively operated and have differing fluid flow requirements. The same general principals may be applied to duplicate the flow control assembly when three, four or more actuators are being operated, even if each has a different flow requirement than the others. If the hydraulic actuator is of the single acting type, so that only one of the lines to the actuator functions as a pressure line, only one flow control valve is required.

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  • Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Civil Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Geology (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
EP82300228A 1981-01-30 1982-01-15 Hydraulische Wahlschaltung mit Stromsteuerung Withdrawn EP0057526A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US22967781A 1981-01-30 1981-01-30
US229677 1981-01-30

Publications (2)

Publication Number Publication Date
EP0057526A2 true EP0057526A2 (de) 1982-08-11
EP0057526A3 EP0057526A3 (de) 1982-08-25

Family

ID=22862242

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82300228A Withdrawn EP0057526A3 (de) 1981-01-30 1982-01-15 Hydraulische Wahlschaltung mit Stromsteuerung

Country Status (7)

Country Link
EP (1) EP0057526A3 (de)
AR (1) AR225582A1 (de)
AU (1) AU7923082A (de)
BR (1) BR8200246A (de)
CA (1) CA1164314A (de)
ES (1) ES509114A0 (de)
ZA (1) ZA82152B (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2846718A1 (fr) * 2002-10-31 2004-05-07 Linde Ag Vanne installee sur un verin

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1987000589A1 (en) * 1985-07-15 1987-01-29 Cave Holdings Pty. Ltd. Hydraulic control unit

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2436899A1 (fr) * 1978-09-22 1980-04-18 Clark Equipment Co Circuit hydraulique de commande

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2436899A1 (fr) * 1978-09-22 1980-04-18 Clark Equipment Co Circuit hydraulique de commande

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
K.KASPERBAUER: "Stromventile" vol. 19, 1972, Otto Krausskopf verlag., Mainz (DT); *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2846718A1 (fr) * 2002-10-31 2004-05-07 Linde Ag Vanne installee sur un verin

Also Published As

Publication number Publication date
AU7923082A (en) 1982-08-05
ES8302222A1 (es) 1982-12-16
ZA82152B (en) 1982-12-29
ES509114A0 (es) 1982-12-16
CA1164314A (en) 1984-03-27
EP0057526A3 (de) 1982-08-25
AR225582A1 (es) 1982-03-31
BR8200246A (pt) 1982-11-23

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Inventor name: CHICHESTER, WILLARD LYLE