EP0756089A3 - Hydraulic control system - Google Patents

Hydraulic control system Download PDF

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Publication number
EP0756089A3
EP0756089A3 EP96117035A EP96117035A EP0756089A3 EP 0756089 A3 EP0756089 A3 EP 0756089A3 EP 96117035 A EP96117035 A EP 96117035A EP 96117035 A EP96117035 A EP 96117035A EP 0756089 A3 EP0756089 A3 EP 0756089A3
Authority
EP
European Patent Office
Prior art keywords
valve
control valve
outlet
liquid
lock
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Withdrawn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
EP96117035A
Other languages
German (de)
French (fr)
Other versions
EP0756089A2 (en
Inventor
Matthew Thomas Miller
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.)
Deere and Co
Original Assignee
Deere and 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 Deere and Co filed Critical Deere and Co
Publication of EP0756089A2 publication Critical patent/EP0756089A2/en
Publication of EP0756089A3 publication Critical patent/EP0756089A3/en
Withdrawn legal-status Critical Current

Links

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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • 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
    • F15B11/003—Systems with load-holding 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
    • 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
    • F15B11/024—Systems essentially incorporating special features for controlling the speed or actuating force of an output member by means of differential connection of the servomotor lines, e.g. regenerative circuits
    • 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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/021—Valves for interconnecting the fluid chambers of an actuator
    • 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
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/20576—Systems with pumps with multiple pumps
    • 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
    • F15B2211/30505—Non-return valves, i.e. check valves
    • F15B2211/3051—Cross-check 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
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-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
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3105—Neutral or centre positions
    • F15B2211/3111—Neutral or centre positions the pump port being closed in the centre position, e.g. so-called closed centre
    • 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
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3144—Directional control characterised by the positions of the valve element the positions being continuously variable, e.g. as realised by proportional 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
    • F15B2211/30—Directional control
    • F15B2211/315—Directional control characterised by the connections of the valve or valves in the circuit
    • F15B2211/3157—Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source, an output member and a return line
    • F15B2211/31576—Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source, an output member and a return line having a single pressure source and a single 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
    • F15B2211/30—Directional control
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/329—Directional control characterised by the type of actuation actuated by fluid pressure

Abstract

Ein druckgesteuertes Hauptsteuerventil (18) verteilt Flüssigkeit zwischen einem hydraulischen Stellglied (12), einer Pumpe (20) und einem Vorratsbehälter (22). Zwischen jedem Arbeitsanschluß (26, 28) des Hauptsteuerventils (18) und einem zugehörigen Stellgliedanschluß (14, 16) ist ein Aussperrventil (44, 46) angeordnet, welches die Flüssigkeitsleckage der Stellgliedanschlüsse (14, 16) vermindert. Jedes Aussperrventil (44, 46) enthält ein durch Druck beeinflußbares Sitzventilteil (56), welches dem Flüssigkeitsdruck in einer Aussperrkammer (50) ausgesetzt ist. Zwischen jedem Aussperrventil (44, 46) und einem zugehörigen Steuerventil (40, 42) ist ein Auslaßsteuerventil (60, 62) angeordnet. Jedes Auslaßsteuerventil (60, 62) enthält ein Auslaßrückschlagventil (66), welches die aus der Aussperrkammer (50) abgelassene Flüssigkeit steuert, sowie einen Auslaßventilkolben (68), der durch Federmittel (72) in eine Lage gedrückt wird, in der er das Auslaßrückschlagventil (66) in seine geschlossene Stellung drängt, so daß die Flüssigkeit nicht aus der Aussperrkammer (50) entweichen kann. Hiedurch können bei einer mittleren Schwimmstellung des Hauptsteuerventils (18) Leckagen an den Stellgliedanschlüssen (14, 16) klein gehalten werden.

Figure 00000001
A pressure-controlled main control valve (18) distributes liquid between a hydraulic actuator (12), a pump (20) and a reservoir (22). A lock-out valve (44, 46) is arranged between each working connection (26, 28) of the main control valve (18) and an associated actuator connection (14, 16), which reduces the fluid leakage of the actuator connections (14, 16). Each lock-out valve (44, 46) contains a pressure-controllable seat valve part (56) which is exposed to the liquid pressure in a lock-out chamber (50). An outlet control valve (60, 62) is arranged between each lockout valve (44, 46) and an associated control valve (40, 42). Each outlet control valve (60, 62) includes an outlet check valve (66) which controls the liquid drained from the lockout chamber (50) and an outlet valve piston (68) which is urged by spring means (72) to position the outlet check valve (66) urges into its closed position so that the liquid cannot escape from the lockout chamber (50). In this way, with a medium floating position of the main control valve (18), leaks at the actuator connections (14, 16) can be kept small.
Figure 00000001
EP96117035A 1993-04-05 1994-03-24 Hydraulic control system Withdrawn EP0756089A3 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US43059 1993-04-05
US08/043,059 US5331882A (en) 1993-04-05 1993-04-05 Control valve system with float valve
EP94104714A EP0623754B1 (en) 1993-04-05 1994-03-24 Hydraulic control system

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP94104714.4 Division 1994-03-24
EP94104714A Division EP0623754B1 (en) 1993-04-05 1994-03-24 Hydraulic control system

Publications (2)

Publication Number Publication Date
EP0756089A2 EP0756089A2 (en) 1997-01-29
EP0756089A3 true EP0756089A3 (en) 1998-03-25

Family

ID=21925249

Family Applications (2)

Application Number Title Priority Date Filing Date
EP96117035A Withdrawn EP0756089A3 (en) 1993-04-05 1994-03-24 Hydraulic control system
EP94104714A Expired - Lifetime EP0623754B1 (en) 1993-04-05 1994-03-24 Hydraulic control system

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP94104714A Expired - Lifetime EP0623754B1 (en) 1993-04-05 1994-03-24 Hydraulic control system

Country Status (7)

Country Link
US (1) US5331882A (en)
EP (2) EP0756089A3 (en)
JP (1) JP3476533B2 (en)
BR (1) BR9401332A (en)
CA (1) CA2119616C (en)
DE (1) DE59403208D1 (en)
ES (1) ES2103514T3 (en)

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US5577532A (en) * 1994-07-11 1996-11-26 Palmer; Thomas W. Valve actuator
JP3478931B2 (en) * 1996-09-20 2003-12-15 新キャタピラー三菱株式会社 Hydraulic circuit
KR100474259B1 (en) * 1996-11-26 2005-06-20 볼보 컨스트럭션 이키프먼트 홀딩 스웨덴 에이비 Hydraulic devices for cylinders for work tools of construction machinery
AT406357B (en) * 1998-10-15 2000-04-25 Hoerbiger Hydraulik ARRANGEMENT FOR HYDRAULICALLY OPERATING A COVER, A REAR COVER OD. DGL.
US6622939B2 (en) * 1999-02-01 2003-09-23 Exactrix Global Systems Apparatus for applying liquid fertilizers and pesticides using a dual stage variable rate distribution manifold
US6186044B1 (en) 1999-03-08 2001-02-13 Caterpillar Inc. Fluid control system with float capability
DE19919015C2 (en) * 1999-04-27 2001-11-15 Sauer Danfoss Nordborg As Nord Hydraulic valve arrangement with locking and floating function
US6173639B1 (en) 1999-05-07 2001-01-16 Caterpillar Inc. Fluid control system having float control
US6389952B1 (en) * 1999-05-28 2002-05-21 Caterpillar Inc. Apparatus and method of operating a fluid cylinder of a work machine
DE19931142C2 (en) * 1999-07-06 2002-07-18 Sauer Danfoss Holding As Nordb Hydraulic valve arrangement with locking function
US6282893B1 (en) 1999-08-19 2001-09-04 Delaware Capital Formation, Inc. Self-contained actuator
US6516706B2 (en) 1999-08-19 2003-02-11 Delaware Capital Formation, Inc. Actuator having internal valve structure
DE19958341A1 (en) * 1999-12-03 2001-07-12 Claas Industrietechnik Gmbh Harvester with front attachment attached
DE10045404C2 (en) * 2000-09-14 2002-10-24 Sauer Danfoss Holding As Nordb Hydraulic valve arrangement
AUPR170400A0 (en) * 2000-11-28 2000-12-21 Ifield Technology Ltd Emergency energy release for hydraulic energy storage systems
JP2004301214A (en) * 2003-03-31 2004-10-28 Hitachi Constr Mach Co Ltd Hydraulic driving device for work vehicle
US7004090B2 (en) * 2003-09-09 2006-02-28 Exactrix Llc Fertilizer injector wing for disc openers
US20050220596A1 (en) * 2004-03-30 2005-10-06 Cnh America Llc Method and apparatus for hydraulically produced ground following of an unloading ramp for a cotton harvester
DE102004020371A1 (en) * 2004-04-23 2005-11-10 Botschafter-Knopff, Ilse Hydraulic control device
CN101253335B (en) * 2005-08-19 2010-06-16 布奇尔液压公司 Oil circuit for controlling a double-action hydraulic drive cylinder
US8424836B2 (en) * 2006-06-16 2013-04-23 Caterpillar Inc. Bidirectional force feedback poppet valve
US20070290152A1 (en) * 2006-06-16 2007-12-20 Pengfei Ma Poppet valve
US20070290151A1 (en) * 2006-06-16 2007-12-20 Matthew Thomas Muller Valve
EP1895169A1 (en) * 2006-09-04 2008-03-05 OIL CONTROL S.p.A. A high pressure relief and control valve assembly
US8893818B2 (en) * 2010-12-17 2014-11-25 Caterpillar Inc. Hydraulic system having dual tilt blade control
US8925439B2 (en) * 2011-01-13 2015-01-06 Husco International, Inc. Valve control valve circuit for operating a single acting hydraulic cylinder
US9725882B2 (en) 2013-01-24 2017-08-08 Volvo Construction Equipment Ab Device and method for controlling flow rate in construction machinery
JP6159629B2 (en) * 2013-09-13 2017-07-05 Ｋｙｂ株式会社 Fluid pressure control device
CN104675780A (en) * 2013-12-02 2015-06-03 江苏神通阀门股份有限公司 Isolating valve for blast-furnace gas power generation pipe network system
CN104482248B (en) * 2014-11-03 2017-05-10 济南数锐电子科技有限公司 Hydraulic operated directional valve
US20170023149A1 (en) * 2015-07-22 2017-01-26 Cnh Industrial America Llc Hydraulic signal control system and method
DE102017117335A1 (en) * 2017-07-31 2019-01-31 Bürkert Werke GmbH & Co. KG Actuation unit for a process valve and process valve
DE112017008022T5 (en) * 2017-09-12 2020-07-02 Shimadzu Corporation CONTROL VALVE
CN108980129B (en) * 2018-07-24 2020-04-07 中国航空工业集团公司西安飞行自动控制研究所 Load holding control valve
US11286643B2 (en) 2018-08-30 2022-03-29 Volvo Construction Equipment Ab Hydraulic circuit for construction equipment
CN117570081A (en) * 2019-02-06 2024-02-20 克斯美库股份有限公司 Air pressure cylinder device with holding valve

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US3943825A (en) * 1972-04-17 1976-03-16 Caterpillar Tractor Co. Hydraulic control system for load supporting hydraulic motors
FR2459894A1 (en) * 1979-06-26 1981-01-16 Poclain Sa Control system for hydraulic ram - contains load limiting device formed by a piloted progressively opening valve
EP0066151A2 (en) * 1981-05-28 1982-12-08 Vickers Incorporated Hydraulic control system comprising a pilot operated check valve
GB2113310A (en) * 1982-01-20 1983-08-03 Rexroth Mannesmann Gmbh Device for controlling a hydromotor
EP0330575A1 (en) * 1988-02-25 1989-08-30 Marrel Hydraulic circuit comprising a safety valve for a hydraulic actuator
EP0331076A1 (en) * 1988-03-03 1989-09-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for cylinder
WO1991019108A1 (en) * 1990-05-26 1991-12-12 Robert Bosch Gmbh Piston-cylinder control device

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Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3943825A (en) * 1972-04-17 1976-03-16 Caterpillar Tractor Co. Hydraulic control system for load supporting hydraulic motors
FR2459894A1 (en) * 1979-06-26 1981-01-16 Poclain Sa Control system for hydraulic ram - contains load limiting device formed by a piloted progressively opening valve
EP0066151A2 (en) * 1981-05-28 1982-12-08 Vickers Incorporated Hydraulic control system comprising a pilot operated check valve
GB2113310A (en) * 1982-01-20 1983-08-03 Rexroth Mannesmann Gmbh Device for controlling a hydromotor
EP0330575A1 (en) * 1988-02-25 1989-08-30 Marrel Hydraulic circuit comprising a safety valve for a hydraulic actuator
EP0331076A1 (en) * 1988-03-03 1989-09-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for cylinder
WO1991019108A1 (en) * 1990-05-26 1991-12-12 Robert Bosch Gmbh Piston-cylinder control device

Also Published As

Publication number Publication date
EP0623754A2 (en) 1994-11-09
EP0623754A3 (en) 1995-03-01
EP0756089A2 (en) 1997-01-29
BR9401332A (en) 1994-10-18
CA2119616A1 (en) 1994-10-06
ES2103514T3 (en) 1997-09-16
US5331882A (en) 1994-07-26
EP0623754B1 (en) 1997-06-25
JPH074403A (en) 1995-01-10
DE59403208D1 (en) 1997-07-31
JP3476533B2 (en) 2003-12-10
CA2119616C (en) 1998-09-01

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