US3908375A - Hydraulic load sensitive pressure and flow compensating system - Google Patents

Hydraulic load sensitive pressure and flow compensating system Download PDF

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Publication number
US3908375A
US3908375A US508977A US50897774A US3908375A US 3908375 A US3908375 A US 3908375A US 508977 A US508977 A US 508977A US 50897774 A US50897774 A US 50897774A US 3908375 A US3908375 A US 3908375A
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Prior art keywords
pressure
flow
valve
compensating
pump
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Expired - Lifetime
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US508977A
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English (en)
Inventor
John E G Young
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SPX Corp
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General Signal Corp
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Publication date
Application filed by General Signal Corp filed Critical General Signal Corp
Priority to US508977A priority Critical patent/US3908375A/en
Priority to CA235,056A priority patent/CA1028922A/en
Priority to JP50114632A priority patent/JPS6110686B2/ja
Priority to IT51468/75A priority patent/IT1047558B/it
Priority to SE7510659A priority patent/SE414526B/sv
Priority to GB39146/75A priority patent/GB1485887A/en
Priority to DE19752542809 priority patent/DE2542809A1/de
Priority to FR7529366A priority patent/FR2286299A1/fr
Application granted granted Critical
Publication of US3908375A publication Critical patent/US3908375A/en
Anticipated expiration legal-status Critical
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
    • F16H61/38—Control of exclusively fluid gearing
    • F16H61/40—Control of exclusively fluid gearing hydrostatic
    • F16H61/46—Automatic regulation in accordance with output requirements
    • 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
    • F15B13/022—Flow-dividers; Priority 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
    • F15B2211/20553—Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
    • 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
    • F15B2211/255—Flow control functions
    • 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
    • F15B2211/31—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
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40523—Flow control characterised by the type of flow control means or valve with flow dividers
    • F15B2211/4053—Flow control characterised by the type of flow control means or valve with flow dividers using 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
    • F15B2211/45—Control of bleed-off flow, e.g. control of bypass flow 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups
    • 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
    • F15B2211/78—Control of multiple output members
    • F15B2211/781—Control of multiple output members one or more output members having priority

Definitions

  • a hydraulic load sensitive pressure and flow compensating system for selectively controlling operation of a plurality of hydraulic motors.
  • the system includes a variable delivery pump having a stroke control cylinder and supplying fluid to the motors through respective motor control valves having variable restricted flow orifices.
  • Pressure sensitive flow dividing valves connect the control valves for delivering surplus flow from one control valve to the next in order according to priority.
  • a pressure and flow compensating valve senses a differential pressure across the last of the control valves in the order of priority and governs the delivery of the variable delivery pump by selectively alternately applying pressure to and releasing pressure from the stroke control cylinder.
  • This invention relates to hydraulic load sensitive pressure and flow compensating systems, and while the invention is subject to a wide range of applications, it will be particularly described as a system for controlling a plurality of hydraulic motors including a variable delivery pump.
  • the present invention is an improvement over the hydraulic load sensitive system disclosed in a Sievenpiper application Ser. No. 393,901, filed Aug. 30, 1973, now abandoned, which is assigned to the same Assignee as the present invention and is herein incorporated by reference.
  • the system according to the Sievenpiper invention provides load sensitive pressure and flow compensating control for a variable delivery pump providing fluid power for operating a plurality of hydraulic motors. Fluid pressure supplied from the pump to the motors is governed by control valves having variable restricted flow orifices. A flow dividing valve is associated with each control valve for delivering surplus flow from one control valve to the next in an order according to priority. Surplus fluid flow from the flow dividing valve associated with the last of the control valves in the order of priority is applied through a restricting orifice to an atmospheric pressure reservoir. The delivery of the pump is controlled by a compensator sensing the rate of flow through the restricting orifice.
  • An object of the present invention is to provide a hydraulic load sensitive pressure and flow compensating system which substantially simplifies the described prior art arrangements.
  • Another object of the present invention is to provide a hydraulic load sensitive pressure and flow compensating system requiring a reduced number of flow dividing valves than is required according to the prior art arrangements.
  • a hydraulic load sensitive pressure and flow compensating system for selectively controlling operation of a plurality of hydraulic motors including a 'variable delivery pump having a stroke control cylinder and supplying fluid to the motors through respective motor control valves having variable restricted flow orifices.
  • Pressure sensitive flow dividing valves are provided connecting the control valves for delivering surplus flow from one control valve to the next in order according to priority.
  • a pressure compensating valve sensing a differential pressure across the last of the con- 'trol valves in the order of priority is provided for gov-
  • FIG. 1 is a schematic drawing illustrating a hydraulic load sensitive pressure and flow compensating system as a preferred embodiment of the present invention
  • FIG. 2 is a schematic longitudinal view, partly in cross section, illustrating a typical valve unit structure that can be used in the preferred embodiment of the present invention as illustrated in FIG. 1;
  • FIG. 3 is a schematic longitudinal view, partly in cross section, illustrating a valve unit structure that can be used in the preferred embodiment of the present invention as illustrated in FIG. 1.
  • a hydraulic load sensitive pressure and flow compensating system for selectively controlling a plurality of operating motors or actuators typically illustrated by motors l0 and 11.
  • the system includes a variable delivery pump 12 having a stroke control cylinder 13 and supplying fluid to the motors and 11 through respective motor control valves 14 and 15 having variable restricting orifices 16.
  • Pressure sensitive flow dividing valves such as valve 17 are provided for connecting the control valves for delivering surplus flow from one control valve to the next in order according to priority.
  • valve 17 is used in delivering surplus flow from control valve 14 to control valve 15.
  • a pressure and flow compensating valve 18 is provided for sensing a differential pressure across the last of the control valves 15 in the order of priority. This valve governs the delivery of the variable delivery pump 12 by selectively alternately applying pressure to, and releasing pressure from, the stroke control cylinder 13.
  • a maximum pressure compensating valve 19 is provided for selectively connecting the pump control cylinder 13 alternately to output of the pump 12 and output to the pressure and flow compensating control valve 18.
  • the pump 12 and maximum pressure compensating valve 19 are combined in a pump unit 20; the control valve 14 and the flow divider valve 17 are combined in an integral valve unit 21; and the control valve 15 and the pressure and flow compensating valve 18 are combined in an integral valve unit 22.
  • control valve 14 has a manually operable plunger or spool 23 having an input control land 24 and exhaust control lands 25 and 26 which cooperate in a conventional manner with an input chamber 27 and exhaust chambers 28 respectively.
  • the lands 24, 25 and 26 have variable restricting orifices 16 for manually determining the rate of flow for an associated motor 10 that is connected to control ports 29 and 30 of the control valve 14.
  • the flow dividing valve 17 has a valve spool 31 biased in a lefthand direction in a bore 32 in the valve unit 12 by a spring 33.
  • the spool 31 has a control land 34 that selectively permits fluid to flow from the input chamber 27 through a chamber 35 and a surplus flow port 36.
  • the port 36 is connected over line 37 of FIG. 1 to the input port of valve unit 22.
  • a chamber 38 at the right of the spool 31 of the flow dividing valve 17 is subjected to pressure in control chamber 39 or control chamber 40, whichever pressure is higher, in accordance with the position of a shuttle valve 41, output of which is connected to chamber 38 through a passage 42.
  • the left-hand end of the spool 31 is subjected to input pressure in chamber 27 by application of such pressure through an axial passageway 43 to the lefthand end of the spool 31.
  • a conventional relief valve 46 is provided in the valve unit 21 to protect the system in case the motor becomes stalled or reaches the end of its stroke.
  • valve unit 22 is similar to valve unit 21 except that the flow divider valve 17 of FIG. 2 is replaced by the pressure compensating valve 18.
  • This valve has a spool 47 having lands 48 and 49 spaced axially by a narrow cavity 50.
  • the lands 48 and 49 have variable restricting orifices 51 adjoining the cavity 50.
  • the spool 47 is subject to actuation by a difference in pressure across the variable restricting orifices 16 the same as for operation of the flow dividing spool 31 (see FIG. 2) in the valve unit 21.
  • Fluid in input chamber 27 of valve unit 22 is applied through an axial passage 52 and an orifice 53 in the spool 47 while fluid pressure on the opposite side of a restricting orifice 16 is applied to the right of the spool 47 through the shuttle valve 41 and passage 42.
  • a port 55 communicates with cavity 50 in the spool 47 and a passage 56 connects port 55 with the maximum pressure compensating valve 19 in pump unit 20 through a stabilizing orifice 57.
  • Maximum pressure compensating valve 19 has a centrally located port 60 communicating with passageway 56 extending to the valve unit 22. It has a right-hand port 61 connected by a passage 62 to output of pump 12 (see FIG. 1). Valve 19 has a spool 63 that is biased by a spring 64 in opposition to pump discharge pressure applied through port 61 to the right of a land 65. Thus spool 63 is normally in its right-hand position as shown where it provides an open passageway to connect the passageway 56 through ports 60 and 66 and passage 67 to the stroke control cylinder 13 of pump 12 (see FIG. 1).
  • a pilot signal is applied to passage 73 for compressing spring 74 in the pressure and flow compensating valve 18 to actuate spool 47 (see FIG. 3) and deliver fluid pressure from exhaust port 55 over passage 56 to input port of the maximum pressure compensating valve 19 in pump unit 20.
  • the spool 63 (see FIG. 3) of maximum pressure compensating valve 19 is in its right-hand position at this time and the land has uncovered the output port 66 to permit pilot pressure to be applied over passage 67 to the stroke control cylinder 13 (see FIG. 1) for destroking pump 12 in accordance with the pressure on flow compensating valve 18 sensing a pressure in excess of I00 p.s.i. input to valve unit 22.
  • This compensation can be provided in valve unit 22 because this is the valve unit for the control of motor 11 that is considered to be the motor having the least priority in the succession of motor control circuits in the system. Should the pilot pressure applied to passage 73 be less than I00 p.s.i., the spool 47 (see FIG.
  • valve 18 is moved to the left to a position to exhaust fluid from stroke control cylinder 13 of the pump 12 over passage 67, through maximum pressure compensator valve 19, over passage 56 through cavity 50 to annular exhaust chamber 75 and to an atmospheric pressure tank 76 that is common to the system.
  • the spool 47 of the pressure and flow compensating valve 18 is reciprocated in a narrow range to alternately apply pressure to and release pressure from the stroke control cylinder 13 as required to maintain the normal minimum pres sure and flow conditions which have been considered, for the purpose of illustration, to be approximately 100 psi. and 1 gallon per minute respectively. This of course maintains minimum wear on the pump 12 and minimum loss due to heating of the fluid under no load conditions.
  • control valve 14 is manually actuated to govern operation of the motor 10 (see FIG. 1). Actuation of this valve in either direction from its center position variably opens a passageway through a restricting orifice 16 to provide the flow desired for operation of the motor 10.
  • the valve unit 21 has its input applied at its pressure port direct from the pump 12
  • the motor 10 has the highest priority, and the flow dividing valve 17 adjusts itself to maintain a constant pressure across the orifice 16 such as a pressure of 100 p.s.i., and any surplus flow is delivered over passage 37 to the input pressure port 72 of valve unit 22.
  • motors l0 and 11 may be controlled by intermediate valve units that are sequentially connected between the first priority valve unit 21 and the last priority valve unit 22, these intermediate units being substantially the same as the typical valve unit 21 that has been described. No matter how many of these intermediate valve units are operated, the valve unit 22 will be operated as has been described to govern by its compensating valve 18 fluid control of the pump 12 through the stroke control cylinder 13 to deliver pressure and flow to meet requirements of the entire system.
  • the associated control valve 15 is manually operated to govern operation of motor 11 in either direction, and such operation, the same as for motor 10, applies fluid to the motor 11 through a variable orifice 16.
  • the spool 47 (see FIG. 3) is now positioned in accordance with a pressure differential across the orifice 16 the same as the control of spool 31 (see FIG. 2) of the flow dividing valve 17 of the valve unit 21. This will cause the spool 47 to adjust fluid applied to the stroke control cylinder 13 of the pump to a point where the differential pressure across the orifice 16 of the valve unit 22 is substantially the normal value which has been assumed to be approximately 100 p.s.i.
  • valve 18 is controlled in a manner similar to the control of valve 17, the lands of spool 47 are different than the lands of spool 31 of flow dividing valve 17. This is because there is no flow dividing action in the pressure and flow compensating valve 18 and thus there is no surplus flow output of valve unit 21.
  • the spool 47 is actuated within a relatively narrow range as determined by the width of the recess 50 and the size of the restricting orifices 51. The extent of reciprocal operation of spool 47 is also limited by end stops 80 and 81 that are spaced relatively short distances from the ends of the spool 47 as is illustrated in FIG. 3.
  • a hydraulic load sensitive pressure and flow compensating sytem for selectively controlling operation of a plurality of hydraulic motors including a variable delivery pump having a stroke control cylinder and supplying fluid to the motors through respective motor control valves having variable restricting orifices .
  • the improvement comprises;
  • pressure sensitive flow dividing means connecting the control valves for delivering surplus flow from one control valve to the next in order according to priority.
  • pressure and flow compensating valve means sensing a differential pressure across a restricting orifice of the last of the control valves in the order of priority for governing the delivery of the variable delivery pump by selectively alternately applying pressure to and releasing pressure from the stroke control cylinder.
  • a hydraulic load sensitive pressure and flow compensating system wherein the pressure compensating valve means selectively connects the pump control cylinder alternately to an atmospheric reservoir and to an upstream passage of the last of the control valves in accordance with the differential pressure across the last of the control valves.
  • a hydraulic load sensitive pressure and flow compensating system comprising a valve that delivers an access flow output in accordance with sensing a difference in upstream and downstream pressures across the restricting orifice of an associated motor control valve.
  • a hydraulic load sensitive pressure and flow compensating system according to claim 1 wherein pump output maximum pressure compensating valve means is provided for selectively connecting the pump control cylinder alternately to output of the pump and output to the pressure compensating control means.
  • a hydraulic load sensitive pressure and flow compensating system according to claim 4 wherein the maximum pressure compensating valve means is operable in response to an overload pressure output of the pump to destroke the pump.
  • a hydraulic load sensitive pressure and flow compensating system according to claim 1 wherein:
  • a first of the control valves comprises a control valve spool for governing the motor having highest priority and a flow divider valve spool disposed in respective bores of an integral valve structure, and
  • the last of the control valves comprises a control spool for governing the motor having the least priority and a pressure compensating valve spool disposed in respective bores of another integral valve Structure.
  • a hydraulic load sensitive pressure and flow compensating system according to claim 6 wherein longitudinal movement of the compensating valvespool selectively alternately applies pressure to and releases pressure from the pump control cylinder.
  • a hydraulic load sensitive pressure and flow compensating system wherein longitudinal movement of the compensating valve spool selects alternately application of fluid pressure to the pump control cylinder and release of pressure from the pump control cylinder to an atmospheric pressure reservoir in accordance with reciprocation of the compensating spool.
  • a hydraulic load sensitive pressure and flow compensating system wherein means is provided for reciprocating the compensating spool by variation of the differential pressure across the restricting orifice of the control valve for the motor having the least priority.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Fluid-Pressure Circuits (AREA)
US508977A 1974-09-25 1974-09-25 Hydraulic load sensitive pressure and flow compensating system Expired - Lifetime US3908375A (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US508977A US3908375A (en) 1974-09-25 1974-09-25 Hydraulic load sensitive pressure and flow compensating system
CA235,056A CA1028922A (en) 1974-09-25 1975-09-09 Hydraulic load sensitive pressure and flow compensating system
JP50114632A JPS6110686B2 (sv) 1974-09-25 1975-09-22
SE7510659A SE414526B (sv) 1974-09-25 1975-09-23 Hydrauliskt belastningskensligt system for kompensering av tryck och flode for selektivt reglerande manovrering av ett flertal hydrauliska motorer i serie
IT51468/75A IT1047558B (it) 1974-09-25 1975-09-23 Perfezionamento nei sistemi di controllo di pressione idraulica
GB39146/75A GB1485887A (en) 1974-09-25 1975-09-24 Hydraulic load sensitive pressure and flow compensating system
DE19752542809 DE2542809A1 (de) 1974-09-25 1975-09-25 Lastgesteuerte kompensationseinrichtung fuer druck und durchsatz in einem hydrauliksystem
FR7529366A FR2286299A1 (fr) 1974-09-25 1975-09-25 Circuit hydraulique a compensation de pression et de debit sensible a la charge

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US508977A US3908375A (en) 1974-09-25 1974-09-25 Hydraulic load sensitive pressure and flow compensating system

Publications (1)

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US3908375A true US3908375A (en) 1975-09-30

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Application Number Title Priority Date Filing Date
US508977A Expired - Lifetime US3908375A (en) 1974-09-25 1974-09-25 Hydraulic load sensitive pressure and flow compensating system

Country Status (8)

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US (1) US3908375A (sv)
JP (1) JPS6110686B2 (sv)
CA (1) CA1028922A (sv)
DE (1) DE2542809A1 (sv)
FR (1) FR2286299A1 (sv)
GB (1) GB1485887A (sv)
IT (1) IT1047558B (sv)
SE (1) SE414526B (sv)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987623A (en) * 1976-01-23 1976-10-26 Caterpillar Tractor Co. Controlled priority fluid system of a crawler type vehicle
US4011721A (en) * 1976-04-14 1977-03-15 Eaton Corporation Fluid control system utilizing pressure drop valve
US4074528A (en) * 1976-08-02 1978-02-21 J. I. Case Company Hydraulic control system with priority flow control
US4116587A (en) * 1977-10-12 1978-09-26 Caterpillar Tractor Co. Load plus differential pressure compensator pump control assembly
US4199942A (en) * 1978-09-28 1980-04-29 Eaton Corporation Load sensing control for hydraulic system
US4479349A (en) * 1981-11-19 1984-10-30 General Signal Corporation Hydraulic control system
US5029067A (en) * 1987-01-30 1991-07-02 Kabushiki Kaisha Komatsu Seisakusho Operation control device
EP1069317A3 (de) * 1999-07-10 2001-11-07 Mannesmann Rexroth AG Wegeventilscheibe, insbesondere für ein mobiles Arbeitsgerät
US20040089496A1 (en) * 2002-11-08 2004-05-13 Nacco Materials Handling Group, Inc. Integrated hydraulic control system
US20120151909A1 (en) * 2010-12-17 2012-06-21 Ace, Accent Controles Electroniques Inc. Load sensing hydraulic system
US20150192151A1 (en) * 2014-01-03 2015-07-09 Danfoss Power Solutions Aps Hydraulic valve arrangement
US20150308625A1 (en) * 2014-04-29 2015-10-29 Robert Bosch Gmbh Hydraulic Control Arrangement for a Plurality of Actuators
US20160377098A1 (en) * 2014-04-11 2016-12-29 Kyb Corporation Valve structure
ITUB20153574A1 (it) * 2015-09-11 2017-03-11 Studio Tecnico 6M Srl Dispositivo di controllo load sensing per valvole prioritarie
US20180187787A1 (en) * 2015-07-10 2018-07-05 Kyb Corporation Rod-shaped member and valve device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2799995A (en) * 1954-04-13 1957-07-23 Vickers Inc Power transmission
US2892311A (en) * 1958-01-08 1959-06-30 Deere & Co Hydraulic apparatus
US3465519A (en) * 1967-08-18 1969-09-09 Webster Electric Co Inc Hydraulic flow controlling apparatus

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3602104A (en) * 1969-07-08 1971-08-31 Eaton Yale & Towne Pressure-compensated flow control
US3878679A (en) * 1973-08-30 1975-04-22 Gen Signal Corp Compensated multi-function hydraulic system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2799995A (en) * 1954-04-13 1957-07-23 Vickers Inc Power transmission
US2892311A (en) * 1958-01-08 1959-06-30 Deere & Co Hydraulic apparatus
US3465519A (en) * 1967-08-18 1969-09-09 Webster Electric Co Inc Hydraulic flow controlling apparatus

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987623A (en) * 1976-01-23 1976-10-26 Caterpillar Tractor Co. Controlled priority fluid system of a crawler type vehicle
US4011721A (en) * 1976-04-14 1977-03-15 Eaton Corporation Fluid control system utilizing pressure drop valve
FR2348526A1 (fr) * 1976-04-14 1977-11-10 Eaton Corp Systeme de commande de fluide utilisant un detendeur
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Also Published As

Publication number Publication date
CA1028922A (en) 1978-04-04
JPS5157380A (sv) 1976-05-19
SE414526B (sv) 1980-08-04
FR2286299A1 (fr) 1976-04-23
SE7510659L (sv) 1976-03-26
FR2286299B1 (sv) 1979-06-29
GB1485887A (en) 1977-09-14
DE2542809A1 (de) 1976-04-08
JPS6110686B2 (sv) 1986-03-31
IT1047558B (it) 1980-10-20

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