DE3268852D1 - Control system for hydraulic circuit apparatus - Google Patents

Control system for hydraulic circuit apparatus

Info

Publication number
DE3268852D1
DE3268852D1 DE8282109083T DE3268852T DE3268852D1 DE 3268852 D1 DE3268852 D1 DE 3268852D1 DE 8282109083 T DE8282109083 T DE 8282109083T DE 3268852 T DE3268852 T DE 3268852T DE 3268852 D1 DE3268852 D1 DE 3268852D1
Authority
DE
Germany
Prior art keywords
control system
hydraulic circuit
circuit apparatus
hydraulic
control
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.)
Expired
Application number
DE8282109083T
Other languages
English (en)
Inventor
Hiroshi Watanabe
Eiki Izumi
Yukio Aoyagi
Kazuo Honma
Kichio Nakajima
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.)
Hitachi Construction Machinery Co Ltd
Original Assignee
Hitachi Construction Machinery Co Ltd
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 Hitachi Construction Machinery Co Ltd filed Critical Hitachi Construction Machinery Co Ltd
Application granted granted Critical
Publication of DE3268852D1 publication Critical patent/DE3268852D1/de
Expired legal-status Critical Current

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2221Control of flow rate; Load sensing arrangements
    • E02F9/2239Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance
    • E02F9/2242Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance including an electronic controller
    • 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
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66CCRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C13/00Other constructional features or details
    • B66C13/18Control systems or devices
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/2025Particular purposes of control systems not otherwise provided for
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2221Control of flow rate; Load sensing arrangements
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2292Systems with two or more pumps
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2278Hydraulic circuits
    • E02F9/2296Systems with a variable displacement pump
    • 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
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • 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
    • F15B21/00Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08Servomotor systems incorporating electrically operated control means
    • F15B21/087Control strategy, e.g. with block diagram
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20546Type of pump variable capacity
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20561Type of pump reversible
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/27Directional control by means of the pressure source
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/305Directional control characterised by the type of valves
    • F15B2211/30505Non-return valves, i.e. check valves
    • F15B2211/30515Load holding valves
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/305Directional control characterised by the type of valves
    • F15B2211/3056Assemblies of multiple valves
    • F15B2211/3059Assemblies of multiple valves having multiple valves for multiple output members
    • F15B2211/30595Assemblies of multiple valves having multiple valves for multiple output members with additional valves between the groups of valves for multiple output members
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/30Directional control
    • F15B2211/32Directional control characterised by the type of actuation
    • F15B2211/327Directional control characterised by the type of actuation electrically or electronically
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/63Electronic controllers
    • F15B2211/6303Electronic controllers using input signals
    • F15B2211/6333Electronic controllers using input signals representing a state of the pressure source, e.g. swash plate angle
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/665Methods of control using electronic components
    • F15B2211/6652Control of the pressure source, e.g. control of the swash plate angle
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/665Methods of control using electronic components
    • F15B2211/6654Flow rate control
    • 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
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71Multiple output members, e.g. multiple hydraulic motors or cylinders

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Operation Control Of Excavators (AREA)
DE8282109083T 1981-10-02 1982-10-01 Control system for hydraulic circuit apparatus Expired DE3268852D1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56156176A JPS5857504A (ja) 1981-10-02 1981-10-02 油圧回路の制御方法

Publications (1)

Publication Number Publication Date
DE3268852D1 true DE3268852D1 (en) 1986-03-13

Family

ID=15622011

Family Applications (1)

Application Number Title Priority Date Filing Date
DE8282109083T Expired DE3268852D1 (en) 1981-10-02 1982-10-01 Control system for hydraulic circuit apparatus

Country Status (5)

Country Link
US (1) US4561249A (de)
EP (1) EP0076485B1 (de)
JP (1) JPS5857504A (de)
KR (1) KR860001715B1 (de)
DE (1) DE3268852D1 (de)

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR910009257B1 (ko) * 1985-09-07 1991-11-07 히다찌 겡끼 가부시기가이샤 유압건설기계의 제어시스템
CN1007632B (zh) * 1985-12-28 1990-04-18 日立建机株式会社 液压建筑机械的控制系统
US5029067A (en) * 1987-01-30 1991-07-02 Kabushiki Kaisha Komatsu Seisakusho Operation control device
US6758356B1 (en) 1989-10-10 2004-07-06 Manitowoc Crane Companies, Inc. Liftcrane with synchronous rope operation
US5189605A (en) * 1989-10-10 1993-02-23 The Manitowoc Company, Inc. Control and hydraulic system for a liftcrane
US5579931A (en) * 1989-10-10 1996-12-03 Manitowoc Engineering Company Liftcrane with synchronous rope operation
US5297019A (en) * 1989-10-10 1994-03-22 The Manitowoc Company, Inc. Control and hydraulic system for liftcrane
GB2250611B (en) * 1990-11-24 1995-05-17 Samsung Heavy Ind System for automatically controlling quantity of hydraulic fluid of an excavator
JP2932892B2 (ja) * 1993-05-27 1999-08-09 ダイキン工業株式会社 超高圧発生装置
US6018895A (en) * 1996-03-28 2000-02-01 Clark Equipment Company Valve stack in a mini-excavator directing fluid under pressure from multiple pumps to actuable elements
AU720849B2 (en) * 1996-03-28 2000-06-15 Clark Equipment Company Multifunction valve stack
US6131751A (en) * 1996-04-26 2000-10-17 Manitowoc Crane Group, Inc. Counter weight handling system and boom parking device
US6481202B1 (en) 1997-04-16 2002-11-19 Manitowoc Crane Companies, Inc. Hydraulic system for boom hoist cylinder crane
US6109030A (en) * 1998-02-13 2000-08-29 Sauer Inc. Apparatus and method for ganging multiple open circuit pumps
US6145287A (en) * 1998-03-05 2000-11-14 Sauer Inc. Hydrostatic circuit for harvesting machine
GB0614534D0 (en) 2006-07-21 2006-08-30 Artemis Intelligent Power Ltd Fluid power distribution and control system
US8966892B2 (en) 2011-08-31 2015-03-03 Caterpillar Inc. Meterless hydraulic system having restricted primary makeup
US8863509B2 (en) 2011-08-31 2014-10-21 Caterpillar Inc. Meterless hydraulic system having load-holding bypass
US8944103B2 (en) 2011-08-31 2015-02-03 Caterpillar Inc. Meterless hydraulic system having displacement control valve
US9057389B2 (en) 2011-09-30 2015-06-16 Caterpillar Inc. Meterless hydraulic system having multi-actuator circuit
US8966891B2 (en) 2011-09-30 2015-03-03 Caterpillar Inc. Meterless hydraulic system having pump protection
US9051714B2 (en) 2011-09-30 2015-06-09 Caterpillar Inc. Meterless hydraulic system having multi-actuator circuit
US9151018B2 (en) 2011-09-30 2015-10-06 Caterpillar Inc. Closed-loop hydraulic system having energy recovery
US8910474B2 (en) 2011-10-21 2014-12-16 Caterpillar Inc. Hydraulic system
US9080310B2 (en) 2011-10-21 2015-07-14 Caterpillar Inc. Closed-loop hydraulic system having regeneration configuration
US8919114B2 (en) * 2011-10-21 2014-12-30 Caterpillar Inc. Closed-loop hydraulic system having priority-based sharing
US8893490B2 (en) * 2011-10-21 2014-11-25 Caterpillar Inc. Hydraulic system
US8978374B2 (en) * 2011-10-21 2015-03-17 Caterpillar Inc. Meterless hydraulic system having flow sharing and combining functionality
US8978373B2 (en) * 2011-10-21 2015-03-17 Caterpillar Inc. Meterless hydraulic system having flow sharing and combining functionality
US8973358B2 (en) * 2011-10-21 2015-03-10 Caterpillar Inc. Closed-loop hydraulic system having force modulation
US9068578B2 (en) 2011-10-21 2015-06-30 Caterpillar Inc. Hydraulic system having flow combining capabilities
US8984873B2 (en) 2011-10-21 2015-03-24 Caterpillar Inc. Meterless hydraulic system having flow sharing and combining functionality
US20130098463A1 (en) * 2011-10-21 2013-04-25 Jeffrey L. Kuehn Meterless hydraulic system having sharing and combining functionality
US8943819B2 (en) 2011-10-21 2015-02-03 Caterpillar Inc. Hydraulic system
US20130098011A1 (en) * 2011-10-21 2013-04-25 Michael L. Knussman Hydraulic system having multiple closed-loop circuits
US20130098013A1 (en) * 2011-10-21 2013-04-25 Brad A. Edler Closed-loop system having multi-circuit flow sharing
US9279236B2 (en) 2012-06-04 2016-03-08 Caterpillar Inc. Electro-hydraulic system for recovering and reusing potential energy
US9290912B2 (en) 2012-10-31 2016-03-22 Caterpillar Inc. Energy recovery system having integrated boom/swing circuits
US9290911B2 (en) 2013-02-19 2016-03-22 Caterpillar Inc. Energy recovery system for hydraulic machine
JP6134614B2 (ja) * 2013-09-02 2017-05-24 日立建機株式会社 作業機械の駆動装置
JP5973979B2 (ja) 2013-11-21 2016-08-23 日立建機株式会社 作業機械の駆動装置
US20150192149A1 (en) * 2014-01-03 2015-07-09 Caterpillar Inc. Apparatus and method for hydraulic systems
CN104006037B (zh) * 2014-06-06 2016-05-11 山东中川液压有限公司 一种三泵式液压挖掘机供油装置
EP3009689B1 (de) 2014-10-15 2021-03-31 Danfoss Power Solutions ApS Hydrauliksystem eines Fahrzeugs
JP6510396B2 (ja) * 2015-12-28 2019-05-08 日立建機株式会社 作業機械
AT518192B1 (de) * 2016-01-22 2017-11-15 Engel Austria Gmbh Hydraulikvorrichtung für eine Formgebungsmaschine
EP3460258B1 (de) * 2017-09-22 2020-09-02 Caterpillar Inc. Maschine mit hydrauliksteuerungssystem und verfahren
DE102019132845A1 (de) * 2019-12-03 2021-06-10 Danfoss Scotland Ltd. Weichenventilbock für eine hydraulisch betätigbare Arbeitsmaschine
DE102019132884A1 (de) * 2019-12-03 2021-06-10 Danfoss Scotland Ltd. Hydrauliksystem mit einem Weichenventilblock für eine hydraulisch betätigbare Arbeitsmaschine

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE448762B (sv) * 1979-02-26 1987-03-16 Hitachi Construction Machinery Hydraulisk drivanordning for konstruktionsmaskinerier, innefattande ett flertal slutna hydraulkretsar
US4369625A (en) * 1979-06-27 1983-01-25 Hitachi Construction Machinery Co., Ltd. Drive system for construction machinery and method of controlling hydraulic circuit means thereof
US4321014A (en) * 1979-12-31 1982-03-23 Polaroid Corporation Constant flow pumping apparatus

Also Published As

Publication number Publication date
JPS5857504A (ja) 1983-04-05
EP0076485A1 (de) 1983-04-13
EP0076485B1 (de) 1986-01-29
KR860001715B1 (ko) 1986-10-18
JPS6319724B2 (de) 1988-04-25
KR840001723A (ko) 1984-05-16
US4561249A (en) 1985-12-31

Similar Documents

Publication Publication Date Title
DE3276254D1 (en) Control system for hydraulic circuit apparatus
DE3268852D1 (en) Control system for hydraulic circuit apparatus
GB2102921B (en) Hydraulic control apparatus
GB2057580B (en) Hydraulic control circuit system
DE3268040D1 (en) Control apparatus for d.c. power transmission system
IL61719A (en) Hydraulic control system
GB8327703D0 (en) Hydraulic control system
GB8319734D0 (en) Fluid system control apparatus
DE3273856D1 (en) Position control apparatus
GB8332882D0 (en) Hydraulic control system
GB2084357B (en) Stabilizing circuit for controlled invertermotor system
DE3260888D1 (en) Hydraulic control apparatus
DE3277576D1 (en) Control circuit system for automobiles
DE3273763D1 (en) Control apparatus
GB2102518B (en) Brake control apparatus
GB2093223B (en) Electro-hydraulic control apparatus
DE3274280D1 (en) Hydraulic control system
DE3364878D1 (en) Hydraulic control system
DE3275399D1 (en) Hydraulic control apparatus
GB2074759B (en) Hydraulic control system
GB2108640B (en) Control apparatus
GB8301585D0 (en) Hydraulic control apparatus
GB8302067D0 (en) Hydraulic control apparatus
AU561166B2 (en) Control unit for phase-contacting apparatus
GB8315137D0 (en) Hydraulic control system

Legal Events

Date Code Title Description
8364 No opposition during term of opposition
8339 Ceased/non-payment of the annual fee