GB1243380A - Hydraulic flow amplifier valve assembly - Google Patents

Hydraulic flow amplifier valve assembly

Info

Publication number
GB1243380A
GB1243380A GB61894/68A GB6189468A GB1243380A GB 1243380 A GB1243380 A GB 1243380A GB 61894/68 A GB61894/68 A GB 61894/68A GB 6189468 A GB6189468 A GB 6189468A GB 1243380 A GB1243380 A GB 1243380A
Authority
GB
United Kingdom
Prior art keywords
rams
valve
spool
fluid
pressure
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
GB61894/68A
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.)
Caterpillar Inc
Original Assignee
Caterpillar Tractor 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 Caterpillar Tractor Co filed Critical Caterpillar Tractor Co
Publication of GB1243380A publication Critical patent/GB1243380A/en
Expired 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
    • F15B13/022—Flow-dividers; Priority valves
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D12/00—Steering specially adapted for vehicles operating in tandem or having pivotally connected frames
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/061—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle provided with effort, steering lock, or end-of-stroke limiters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/08—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by type of steering valve used
    • 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
    • F15B11/162—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for giving priority to particular servomotors or users
    • 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
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/0416—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor with means or adapted for load sensing
    • F15B13/0417—Load sensing elements; Internal fluid connections therefor; Anti-saturation or pressure-compensation 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
    • 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
    • F15B2211/3053—In combination with a pressure compensating valve
    • F15B2211/30535—In combination with a pressure compensating valve the pressure compensating valve is arranged between pressure source and 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
    • 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
    • F15B2211/50—Pressure control
    • F15B2211/57—Control of a differential 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
    • F15B2211/60—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
    • F15B2211/6054—Load sensing circuits having valve means between output member and the load sensing circuit using shuttle 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
    • F15B2211/605—Load sensing circuits
    • F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
    • F15B2211/6055—Load sensing circuits having valve means between output member and the load sensing circuit using 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
    • F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve means
    • 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
    • F15B2211/7114—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators
    • F15B2211/7128—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators the chambers being connected in parallel
    • 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
    • F15B2211/75—Control of speed of the output member

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Power Steering Mechanism (AREA)

Abstract

1,243,380. Power steering mechanism. CATERPILLAR TRACTOR CO. 31 Dec., 1968 [13 March, 1968], No. 61894/68. Heading B7H. In vehicle steering mechanism including an amplifier valve assembly 26 for regulating flow of pressure fluid from a pump 18 to hydraulic steering rams 16, 17 in response to operation of a metering unit 21 by a steering wheel to transfer fluid across the metering unit at a rate proportional to the desired rate of operation of the steering rams, the amplifier valve assembly 26 comprises a steering control valve 29 operated by fluid flow from the metering unit 21 to direct fluid from the pump 18 to the rams 16, 17 at an amplified rate proportional to the flow from the metering unit, and a compensating valve 33 bleeds fluid from an inlet passage 61 fed by the pump 18 to regulate the pressure therein. The control valve 29 includes a spool 42 centralized in a bore 44 by springs 51, 52 and having at its ends chambers 48, 49 which communicate through conduits 53, 54, a lock valve 37 and conduits 23, 24 with the metering unit 21. Each end of the spool 42 has a slot 73 which is just out of communication with a respective recess 57, 59 connected by a passage 56, 58 with the opposite chamber 48, 49. A central land 66 on the spool 42 prevents communication between the inlet passage 61 and two chambers 67, 68 connected to the rams 16, 17 through a blocker valve 36, outlet passages 76, 77 and conduits 31, 32. Two further lands 69, 71 on the spool 42 control communication between the chambers 67, 68 and drain passages 62, 63 connected through a conduit 64 to a drain tank 27. When the metering unit 21 is operated by rotation of the steering wheel fluid is delivered to one of the chambers 48, 49 so that increased pressure therein displaces the spool 42 to such an extent that the corresponding groove 73 communicates sufficiently with the respective recess 57, 59 to relieve the pressure. Such movement of the spool 42 results in the land 66 opening communication between the inlet passage 61 and the appropriate chamber 67, 68 by the necessary amount for fluid from the pump 18 to flow to the rams 16, 17 at an amplified rate proportional to the rate of flow through the groove 73. The compensating valve 33 regulates the pressure in the inlet passage 61 in such a way that the pressure drop across the land 66 varies according to the resistance encountered by the rams 16, 17 and is loaded by a spring 92 and subjected to the pressure in the chamber 67 or 68 through a shuttle valve 94 and a passage 93. The blocker valve 36 includes a spool 43 which prevents communication between the chamber 67, 68 and outlet passages 76, 77 to fix the position of the rams 16, 17 unless the control valve 29 is operated. Should external forces create excessive pressure in the rams 16, 17 the blocker valve 36 opens to vent fluid from the rams through the shuttle valve 94 and passage 93 to a relief valve 41. The lock valve 37 includes a spool 98 which is normally moved against spring loading 104 by pump output pressure acting thereon through a conduit 102 and a slug 103 into a position wherein the conduits 23, 24 and 53, 54 are in respective communication. The spool 98 is further moved against additional spring loading 106 in the event of excessive pressure to isolate the conduits 23, 24, and when the pump 18 is not operating the spring loading 104 moves the spool 98 into a position wherein the conduits 23, 24 are connected to the conduits 31, 32 through conduits 38, 39 so that the rams 16, 17 can be manually operated from the metering unit 21. The rams 16, 17 are connected between the frame sections 12, 13 of an articulated vehicle wherein limiting valves 112, 113 connected in the conduits 23, 24 cooperate with stops 116, 117 to limit relative turning of the frame sections. Each limiting valve 112, 113 includes a spool, Fig. 2 (not shown), displaceable upon engagement with the respective stop 116, 117 to vent the conduit 23 or 24 and halt the turning movement. The amplification ratio of the control valve may be made variable by providing solenoid-controlled means, Fig. 3 (not shown), for varying the spring loading acting on the compensating valve. In another embodiment, Fig. 4 (not shown), the control valve includes a pair of spools each having therein a first orifice through which the metering unit communicates with the steering rams and a second orifice through which fluid from the pump flows to the rams, flow through the first orifice creating a pressure drop which shifts the spool so that fluid flows across the second orifice with an equivalent pressure drop. In a further embodiment, Fig. 5 (not shown), the control valve and blocker valve comprise a single spool which moves in response to fluid flow from the metering unit to maintain equal pressure drops across first and second fixed orifices through which the metering unit and the pump respectively communicate with the steering rams.
GB61894/68A 1968-03-13 1968-12-31 Hydraulic flow amplifier valve assembly Expired GB1243380A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US71274768A 1968-03-13 1968-03-13

Publications (1)

Publication Number Publication Date
GB1243380A true GB1243380A (en) 1971-08-18

Family

ID=24863401

Family Applications (1)

Application Number Title Priority Date Filing Date
GB61894/68A Expired GB1243380A (en) 1968-03-13 1968-12-31 Hydraulic flow amplifier valve assembly

Country Status (5)

Country Link
US (1) US3566749A (en)
BE (1) BE728135A (en)
DE (1) DE1912612A1 (en)
FR (1) FR2003760A1 (en)
GB (1) GB1243380A (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3903787A (en) * 1971-12-23 1975-09-09 Caterpillar Tractor Co Low-effort proportional control valve
US3847180A (en) * 1971-12-23 1974-11-12 Caterpillar Tractor Co Low effort, proportional control valve
US3799200A (en) * 1972-06-12 1974-03-26 Gardner Denver Co Flow and pressure regulating control for hydraulic motors
DE2249181C3 (en) * 1972-10-06 1979-07-19 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen Hydraulic steering limitation for power steering systems, in particular for motor vehicles
DE2257230C3 (en) * 1972-11-22 1975-06-26 Danfoss A/S, Nordborg (Daenemark) Hydraulic steering device
US3862643A (en) * 1973-02-26 1975-01-28 Caterpillar Tractor Co Pilot pump bleed control for earthmoving scrapers
US3880181A (en) * 1973-05-03 1975-04-29 Finn Feroy Hydraulic control system
JPS5032624U (en) * 1973-07-18 1975-04-09
US3995532A (en) * 1974-07-15 1976-12-07 Caterpillar Tractor Co. Proportional control valve with preconditioned inlet modulating relief valve
US4148248A (en) * 1975-03-11 1979-04-10 Maxton Manufacturing Company Hydraulic valve control system
US4204460A (en) * 1976-01-21 1980-05-27 Danfoss A/S Arrangement for influencing the operating quantity of a servo-motor
US4109748A (en) * 1977-02-28 1978-08-29 Towmotor Corporation Steering apparatus
USRE31125E (en) * 1977-04-06 1983-01-18 Massey-Ferguson Inc. Articulated vehicle steering system
DE2932847C2 (en) * 1979-08-14 1982-05-13 Danfoss A/S, 6430 Nordborg Hydraulic control device for a servomotor, in particular for vehicle steering
US4336687A (en) * 1980-04-21 1982-06-29 Eaton Corporation Load sensing controller
DE3107915C2 (en) * 1981-03-02 1985-12-05 Danfoss A/S, Nordborg Hydraulic control device, in particular steering device
US4917205A (en) * 1987-03-23 1990-04-17 Mitsubishi Jidosha Kogyo Kabushiki Kaisha Four-wheel steering system
DE3817031C2 (en) * 1988-05-19 1994-02-24 Danfoss As Steering damper for a kink-controlled vehicle with hydraulic steering
US4914913A (en) * 1989-05-03 1990-04-10 Caterpillar Inc. Load responsive flow amplified control system for power steering
US5117935A (en) * 1990-12-21 1992-06-02 Caterpillar Inc. Load sensing hydrostatic steering system
US7306071B2 (en) * 2002-04-25 2007-12-11 Bosch Rexroth Ag Hydraulic steering apparatus
DE10254246B4 (en) * 2002-08-08 2013-03-21 Bosch Rexroth Aktiengesellschaft control arrangement
US7984785B2 (en) 2008-02-28 2011-07-26 Eaton Corporation Control valve assembly for electro-hydraulic steering system
US7931112B2 (en) * 2008-05-02 2011-04-26 Eaton Corporation Isolation valve for a load-reaction steering system
US8316757B2 (en) * 2009-12-04 2012-11-27 Walvoil Fluid Power Corp. Hydraulic control valve assembly with monolithic body and single spool port lock
CN102673640B (en) * 2012-06-14 2014-08-13 航天重型工程装备有限公司 Hydraulic steering system
IL230327B (en) 2014-01-01 2019-11-28 Israel Aerospace Ind Ltd Interception missile and warhead therefor
CN108468671B (en) * 2018-05-04 2023-09-26 贵阳海之力液压有限公司 Flow matching valve suitable for asymmetric closed loop
JP7095589B2 (en) * 2018-12-26 2022-07-05 株式会社豊田自動織機 Hydraulic drive for industrial vehicles
CN114576228B (en) * 2022-05-06 2022-07-22 英轩重工有限公司 Flow amplifying valve and steering hydraulic control system thereof

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US2020951A (en) * 1933-05-20 1935-11-12 Joseph R Lemon Hydraulic steering system
USRE25036E (en) * 1957-04-19 1961-09-12 Fluid power steering system
US2936037A (en) * 1959-02-25 1960-05-10 Allis Chalmers Mfg Co Hydraulic control system
US3198088A (en) * 1963-08-13 1965-08-03 Caterpillar Tractor Co Fluid motor control system
GB1051690A (en) * 1963-08-19
US3249173A (en) * 1963-12-20 1966-05-03 Clark Equipment Co Power steering system
US3320745A (en) * 1965-10-04 1967-05-23 Weatherhead Co Hydraulic steering control
US3326317A (en) * 1965-10-22 1967-06-20 Int Harvester Co Fluid power steering system
US3347041A (en) * 1965-10-23 1967-10-17 Weatherhead Co Hydraulic steering system
US3410306A (en) * 1966-10-27 1968-11-12 Gen Signal Corp Control valve with lockout element
DE163870C (en) * 1966-12-30
US3394545A (en) * 1967-03-02 1968-07-30 Weatherhead Co Hydraulic steering system

Also Published As

Publication number Publication date
BE728135A (en) 1969-08-07
DE1912612A1 (en) 1969-10-09
FR2003760A1 (en) 1969-11-14
US3566749A (en) 1971-03-02

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