EP1387089A3 - Hydraulic actuator circuit - Google Patents

Hydraulic actuator circuit Download PDF

Info

Publication number
EP1387089A3
EP1387089A3 EP03254648A EP03254648A EP1387089A3 EP 1387089 A3 EP1387089 A3 EP 1387089A3 EP 03254648 A EP03254648 A EP 03254648A EP 03254648 A EP03254648 A EP 03254648A EP 1387089 A3 EP1387089 A3 EP 1387089A3
Authority
EP
European Patent Office
Prior art keywords
valve
circuit
hydraulic actuator
opening
holding
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Withdrawn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
EP03254648A
Other languages
German (de)
French (fr)
Other versions
EP1387089A2 (en
Inventor
Yutaka Kobelco Const. Machinery Co. Ltd. Toji
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.)
Kobelco Construction Machinery Co Ltd
Original Assignee
Kobelco 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 Kobelco Construction Machinery Co Ltd filed Critical Kobelco Construction Machinery Co Ltd
Publication of EP1387089A2 publication Critical patent/EP1387089A2/en
Publication of EP1387089A3 publication Critical patent/EP1387089A3/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Withdrawn legal-status Critical Current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
    • F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • F15B20/005—Leakage; Spillage; Hose burst
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/226—Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2296—Systems with a variable displacement pump
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20546—Type of pump variable capacity
    • 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
    • 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
    • F15B2211/30515—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
    • 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
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/30565—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve
    • F15B2211/3058—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-valve having additional valves for interconnecting the fluid chambers of a double-acting actuator, e.g. for regeneration mode or for floating mode
    • 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
    • F15B2211/3116—Neutral or centre positions the pump port being open in the centre position, e.g. so-called open 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
    • F15B2211/3138—Directional control characterised by the positions of the valve element the positions being discrete
    • 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
    • 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
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40576—Assemblies of multiple valves
    • F15B2211/40584—Assemblies of multiple valves the flow control means arranged in parallel with a check 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
    • F15B2211/41—Flow control characterised by the positions of the valve element
    • F15B2211/413—Flow 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
    • F15B2211/40—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
    • F15B2211/42—Flow control characterised by the type of actuation
    • F15B2211/421—Flow control characterised by the type of actuation mechanically
    • F15B2211/422—Flow control characterised by the type of actuation mechanically actuated by biasing means, e.g. spring-actuated
    • 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
    • F15B2211/42—Flow control characterised by the type of actuation
    • F15B2211/428—Flow 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
    • F15B2211/40—Flow control
    • F15B2211/46—Control of flow in the return line, i.e. meter-out control
    • 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
    • F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/863—Control during or prevention of abnormal conditions the abnormal condition being a hydraulic or pneumatic failure
    • F15B2211/8636—Circuit failure, e.g. valve or hose failure

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Civil Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Structural Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Operation Control Of Excavators (AREA)
  • Component Parts Of Construction Machinery (AREA)

Abstract

This invention provides with a hydraulic actuator circuit comprising a holding valve (17) disposed in a boom extension-side pipeline (13) in the circuit an opening of which is controlled by a control valve (15) and an assist cylinder (20) for controlling an opening of the holding valve in such a way that, in a condition wherein a holding pressure drops to a valve of not larger than a given value, the opening of the holding valve is reduced, whereby the circuit can prevent an unusual sudden lowering of a boom with a load.
EP03254648A 2002-07-30 2003-07-25 Hydraulic actuator circuit Withdrawn EP1387089A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2002222000 2002-07-30
JP2002222000A JP3915622B2 (en) 2002-07-30 2002-07-30 Load holding device for hydraulic actuator circuit

Publications (2)

Publication Number Publication Date
EP1387089A2 EP1387089A2 (en) 2004-02-04
EP1387089A3 true EP1387089A3 (en) 2008-03-05

Family

ID=30112942

Family Applications (1)

Application Number Title Priority Date Filing Date
EP03254648A Withdrawn EP1387089A3 (en) 2002-07-30 2003-07-25 Hydraulic actuator circuit

Country Status (2)

Country Link
EP (1) EP1387089A3 (en)
JP (1) JP3915622B2 (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE502005000989D1 (en) * 2005-08-11 2007-08-16 Hawe Hydraulik Gmbh & Co Kg Electrohydraulic device
JP4890147B2 (en) * 2006-08-04 2012-03-07 日立建機株式会社 Load holding device for hydraulic actuator circuit
JP5091034B2 (en) * 2008-07-03 2012-12-05 日立建機株式会社 Hydraulic circuit equipment for construction machinery
JP5266150B2 (en) * 2009-06-18 2013-08-21 太平電業株式会社 Hydraulic circuit for high pressure hydraulic system
JP6397715B2 (en) * 2014-10-06 2018-09-26 Ｋｙｂ−Ｙｓ株式会社 Fluid pressure control device
CN205154812U (en) * 2015-10-28 2016-04-13 民航协发机场设备有限公司 Two -way ferry vehicle lock bridge hydraulic system that traveles
IT201600106112A1 (en) * 2016-10-21 2018-04-21 Atlantic Fluid Tech S R L ANTI-TUBE BREAK DEVICE
JP6982517B2 (en) * 2018-02-27 2021-12-17 Ｋｙｂ−Ｙｓ株式会社 Fluid pressure controller
CN111868338B (en) * 2018-03-22 2022-07-26 住友重机械工业株式会社 Excavator
IT201800004555A1 (en) * 2018-04-16 2019-10-16 PIPE BREAKAGE PROTECTION DEVICE
JP7171249B2 (en) 2018-06-08 2022-11-15 株式会社アイチコーポレーション Safety device for aerial work platform
EP3862576A1 (en) * 2020-02-10 2021-08-11 Robert Bosch GmbH Control system for an actuator cylinder of a crane

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0331076A1 (en) * 1988-03-03 1989-09-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for cylinder
DE4342565A1 (en) * 1993-12-14 1995-06-22 Bosch Gmbh Robert Vertical operating support axis
JPH10267009A (en) * 1997-03-25 1998-10-06 Toshiba Mach Co Ltd Load hold switching valve device
EP0952358A2 (en) * 1998-04-21 1999-10-27 Hitachi Construction Machinery Co., Ltd. Hose rupture control valve unit
US6173639B1 (en) * 1999-05-07 2001-01-16 Caterpillar Inc. Fluid control system having float control

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0357507A (en) 1989-07-26 1991-03-12 Kobe Steel Ltd Method for controlling meandering of plate under rolling

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0331076A1 (en) * 1988-03-03 1989-09-06 KABUSHIKI KAISHA KOBE SEIKO SHO also known as Kobe Steel Ltd. Hydraulic circuit for cylinder
DE4342565A1 (en) * 1993-12-14 1995-06-22 Bosch Gmbh Robert Vertical operating support axis
JPH10267009A (en) * 1997-03-25 1998-10-06 Toshiba Mach Co Ltd Load hold switching valve device
EP0952358A2 (en) * 1998-04-21 1999-10-27 Hitachi Construction Machinery Co., Ltd. Hose rupture control valve unit
US6173639B1 (en) * 1999-05-07 2001-01-16 Caterpillar Inc. Fluid control system having float control

Also Published As

Publication number Publication date
EP1387089A2 (en) 2004-02-04
JP3915622B2 (en) 2007-05-16
JP2004060821A (en) 2004-02-26

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