GB2501486A - Work machine having a hydraulic system comprising variable orifice ratios - Google Patents

Work machine having a hydraulic system comprising variable orifice ratios Download PDF

Info

Publication number
GB2501486A
GB2501486A GB1207161.9A GB201207161A GB2501486A GB 2501486 A GB2501486 A GB 2501486A GB 201207161 A GB201207161 A GB 201207161A GB 2501486 A GB2501486 A GB 2501486A
Authority
GB
United Kingdom
Prior art keywords
orifice
ratio
mode
pressure
pump
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Withdrawn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
GB1207161.9A
Other languages
English (en)
Other versions
GB201207161D0 (en
Inventor
Harish Narotham
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.)
JC Bamford Excavators Ltd
Original Assignee
JC Bamford Excavators 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 JC Bamford Excavators Ltd filed Critical JC Bamford Excavators Ltd
Priority to GB1207161.9A priority Critical patent/GB2501486A/en
Publication of GB201207161D0 publication Critical patent/GB201207161D0/en
Priority to EP13162367.0A priority patent/EP2657537A3/en
Priority to US13/866,757 priority patent/US20130280097A1/en
Priority to JP2013089397A priority patent/JP2013228101A/ja
Priority to CN2013101460436A priority patent/CN103375450A/zh
Publication of GB2501486A publication Critical patent/GB2501486A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • 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
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/165—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for adjusting the pump output or bypass in response to demand
    • 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
    • E02F9/2264—Arrangements or adaptations of elements for hydraulic drives
    • 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
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force 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
    • 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
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
    • F15B11/168—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load with an isolator valve (duplicating valve), i.e. at least one load sense [LS] pressure is derived from a work port load sense pressure but is not a work port pressure itself
    • 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
    • F15B2211/20538—Type of pump constant 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
    • F15B2211/20—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
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/25—Pressure control functions
    • F15B2211/253—Pressure margin control, e.g. pump pressure in relation to load 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
    • F15B2211/40507—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
    • F15B2211/50—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
    • F15B2211/50536—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using unloading valves controlling the supply pressure by diverting fluid 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/605—Load sensing circuits
    • F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
    • 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/605—Load sensing circuits
    • F15B2211/6058—Load sensing circuits with isolator 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/65—Methods of control of the load sensing pressure
    • F15B2211/651—Methods of control of the load sensing pressure characterised by the way the load pressure is communicated to the load sensing circuit
    • 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/65—Methods of control of the load sensing pressure
    • F15B2211/653—Methods of control of the load sensing pressure the load sensing pressure being higher than the load pressure

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Operation Control Of Excavators (AREA)
GB1207161.9A 2012-04-24 2012-04-24 Work machine having a hydraulic system comprising variable orifice ratios Withdrawn GB2501486A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
GB1207161.9A GB2501486A (en) 2012-04-24 2012-04-24 Work machine having a hydraulic system comprising variable orifice ratios
EP13162367.0A EP2657537A3 (en) 2012-04-24 2013-04-04 A hydraulic system
US13/866,757 US20130280097A1 (en) 2012-04-24 2013-04-19 Hydraulic system
JP2013089397A JP2013228101A (ja) 2012-04-24 2013-04-22 油圧システム
CN2013101460436A CN103375450A (zh) 2012-04-24 2013-04-24 液压系统

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1207161.9A GB2501486A (en) 2012-04-24 2012-04-24 Work machine having a hydraulic system comprising variable orifice ratios

Publications (2)

Publication Number Publication Date
GB201207161D0 GB201207161D0 (en) 2012-06-06
GB2501486A true GB2501486A (en) 2013-10-30

Family

ID=46261777

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1207161.9A Withdrawn GB2501486A (en) 2012-04-24 2012-04-24 Work machine having a hydraulic system comprising variable orifice ratios

Country Status (5)

Country Link
US (1) US20130280097A1 (ja)
EP (1) EP2657537A3 (ja)
JP (1) JP2013228101A (ja)
CN (1) CN103375450A (ja)
GB (1) GB2501486A (ja)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9435105B2 (en) * 2014-05-07 2016-09-06 Deere & Company Method and system for controlling pump outlet pressure between different operating modes
US10378184B2 (en) 2015-06-16 2019-08-13 Volvo Construction Equipment Ab Load sensing hydraulic system for a working machine
US9662787B1 (en) * 2015-09-25 2017-05-30 Google Inc. Hydraulic pressure variation in a legged robot
US10323458B2 (en) * 2016-10-21 2019-06-18 Caterpillar Inc. Dual pressure logic for a track drill circuit
US11313388B1 (en) 2021-01-29 2022-04-26 Cnh Industrial America Llc System and method for controlling hydraulic fluid flow within a work vehicle
US11530524B2 (en) 2021-01-29 2022-12-20 Cnh Industrial America Llc System and method for controlling hydraulic fluid flow within a work vehicle
US11261582B1 (en) 2021-01-29 2022-03-01 Cnh Industrial America Llc System and method for controlling hydraulic fluid flow within a work vehicle using flow control valves
US11143211B1 (en) 2021-01-29 2021-10-12 Cnh Industrial America Llc System and method for controlling hydraulic fluid flow within a work vehicle
US11921525B1 (en) 2022-11-25 2024-03-05 Pratt & Whitney Canada Corp. System and method for controlling fluid flow with a pressure relief valve

Citations (4)

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Publication number Priority date Publication date Assignee Title
WO2010046723A1 (en) * 2008-10-23 2010-04-29 Volvo Compact Equipment Sas Skid steer machine with automatic operating ratio change system
CN201553113U (zh) * 2009-08-27 2010-08-18 天津建筑机械厂 一种履带式牵引机的液压系统
JP2011075048A (ja) * 2009-09-30 2011-04-14 Hitachi Constr Mach Co Ltd 油圧建設機械の油圧駆動装置
WO2012005391A1 (ko) * 2010-07-06 2012-01-12 볼보 컨스트럭션 이큅먼트 에이비 하이브리드식 굴삭기의 마력제어 시스템 및 그의 제어방법

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JPS54162353A (en) * 1978-06-13 1979-12-22 Toshiba Corp Hydraulic circuit for driving cargo handling apparatus
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DE3722083C1 (de) * 1987-07-03 1988-09-15 Heilmeier & Weinlein Hydraulische Steuervorrichtung
DE3807583C1 (ja) * 1988-03-08 1989-03-09 Heilmeier & Weinlein Fabrik Fuer Oel-Hydraulik Gmbh & Co Kg, 8000 Muenchen, De
DE3844401C2 (de) * 1988-12-30 1994-10-06 Rexroth Mannesmann Gmbh Regeleinrichtung für eine Verstellpumpe
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JP4128482B2 (ja) * 2002-04-30 2008-07-30 東芝機械株式会社 油圧制御システム
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SE534002C2 (sv) * 2009-06-24 2011-03-29 Nordhydraulic Ab Förfarande och anordning för styrning av ett hydraliskt system
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Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010046723A1 (en) * 2008-10-23 2010-04-29 Volvo Compact Equipment Sas Skid steer machine with automatic operating ratio change system
CN201553113U (zh) * 2009-08-27 2010-08-18 天津建筑机械厂 一种履带式牵引机的液压系统
JP2011075048A (ja) * 2009-09-30 2011-04-14 Hitachi Constr Mach Co Ltd 油圧建設機械の油圧駆動装置
WO2012005391A1 (ko) * 2010-07-06 2012-01-12 볼보 컨스트럭션 이큅먼트 에이비 하이브리드식 굴삭기의 마력제어 시스템 및 그의 제어방법

Also Published As

Publication number Publication date
CN103375450A (zh) 2013-10-30
GB201207161D0 (en) 2012-06-06
JP2013228101A (ja) 2013-11-07
EP2657537A3 (en) 2016-03-09
EP2657537A2 (en) 2013-10-30
US20130280097A1 (en) 2013-10-24

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