GB2224780A - Hydraulic control circuit for a motor vehicle - Google Patents

Hydraulic control circuit for a motor vehicle Download PDF

Info

Publication number
GB2224780A
GB2224780A GB8917320A GB8917320A GB2224780A GB 2224780 A GB2224780 A GB 2224780A GB 8917320 A GB8917320 A GB 8917320A GB 8917320 A GB8917320 A GB 8917320A GB 2224780 A GB2224780 A GB 2224780A
Authority
GB
United Kingdom
Prior art keywords
valve
consumer
priority
pressure
hydraulic
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.)
Granted
Application number
GB8917320A
Other versions
GB8917320D0 (en
GB2224780B (en
Inventor
Wolfgang Kauss
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.)
Bosch Rexroth AG
Original Assignee
Mannesmann Rexroth AG
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 Mannesmann Rexroth AG filed Critical Mannesmann Rexroth AG
Publication of GB8917320D0 publication Critical patent/GB8917320D0/en
Publication of GB2224780A publication Critical patent/GB2224780A/en
Application granted granted Critical
Publication of GB2224780B publication Critical patent/GB2224780B/en
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/12—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid
    • B60T13/16—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid using pumps directly, i.e. without interposition of accumulators or reservoirs
    • B60T13/168—Arrangements for pressure supply
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/321—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration deceleration
    • B60T8/328—Systems sharing components with other fluid systems onboard the vehicle
    • 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
    • B62D5/07—Supply of pressurised fluid for steering also supplying other consumers ; control thereof
    • 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
    • F15B2211/50554—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure downstream of the pressure control means, e.g. pressure reducing 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
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50563—Pressure control characterised by the type of pressure control means the pressure control means controlling 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
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5151—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source 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
    • F15B2211/60—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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Power Steering Mechanism (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Valves And Accessory Devices For Braking Systems (AREA)

Description

2224780 1 - HYDRAULIC CONTROL CIRCUIT FOR A MOTOR VEHICLE The invention
relates to a hydraulic control circuit for a motor vehicle.
Hydraulic brake systems and steering systems in vehicles must be supplied with the respective pressure fluid controlled with respect to is pressure level in such a way that reliable functioning is guaranteed under all operating conditions. At the same time, at least one further secondary consumer is generally supplied via the hydraulic system, which in the simplest embodiment has only one supply pump. Where two priority valves are used for supplying three consumers, the hydraulic pressure protection is here ensured only for two of the consumers while a third consumer, which, for example, operates at a lower pressure, makes a pressure protection by non- hydraulic means necessary.
An object on which the invention is based is to create a hydraulic control circuit of the above- indicated type which makes possible a hydraulic limitation of the maximum pressure to the individual consumers for different working pressures.
The invention includes a hydraulic control circuit for a motor vehicle for one or more consumers to be supplied as a matter of priority. such as f or example for a brake valve supplied via a priority valve by a pump which is simultaneously used for supplying at least one secondary consumer and one 2 further consumer, e.g. the steering circuit, said circuit comprising two priority valves connected in series, of which the upstream priority valve supplies at least one secondary consumer and divides off a common preferential flow for two further consumers to the downstream priority valve for supplying as a matter of priority the first of said two further consumers wherein the maximum pressures of the secondary consumer and of the first further consumer are in each case limited by a respective pressure relief valve, and the maximum pressure of the second further consumer is limited to below that of the first further consumer by the downstream priority valve, being co.nzrolled on both sides by pressure in the supply line to the first further consumer, the pressure on the spring side of the downstream priority valve being increased via a control line by a control valve in order to bring the priority valve into a throttling position for the supply line to the second further consumer, which, via a load-indicating line thereof, controls the control valve.
Whereas pressure relief valves which are known per se limit the maximum pressures of a third consumer and a first consumer, the control valve makes it possible to limit the maximum pressure of the second consumer to below the maximum pressure of the first consumer. If the pressure in the load-indicating line of the second consumer reaches the value set by the spring of the control valve, the control sides of the second priority valve are connected to one another to such an extent that this valve only permits the volumetric flow to the second consumer which is necessary in order to maintain at the second consumer the maximum pressure set by the control valve.
The invention also includes a hydraulic control arrangement for controlling hydraulic fluid supply to two consumers such that the supply to one has priority, the arrangement comprising a priority valve with respective supply lines for supplying hydraulic fluid to the two consumers and having a slidable valve element on one end of which a spring f orce acts to bias the valve element in one direction, respective hydraulic lines j'or enabling hydraulic f luid at the pressure in the supply line to the consumer having priority to act on both ends of the slidable valve element, and a control valve in the hydraulic line associated with said one end of the valve element for controlling hydraulic fluid flow therein, the operation of which control valve is controlled by the pressure of the hydraulic f luid in a load indicating line of the other consumer.
In order that the invention may be well understood, an embodiment thereof, which is given by way of example only, will now be described with reference to the accompanying drawing of a hydraulic circuit.
In the drawing, 20 indicates a hydraulic pump which, via a differential pressure regulator 1, supplies the overall hydraulic system of a commercial vehicle with a trailer. In particular, the pump 20 supplies a first consumer V I, e.g. the steering system, a second consumer V II, e.g. brakes, and at least one secondary consumer V III. The load state of these consumers is in each case detected via an orifice plate which is linked, when the consumer is not loaded, to the tank and, otherwise, to an associated load-indicating line 15 or 17 or 18 respectively, via which the maximum pressure at the consumers is limited. Thus the consumer V III is connected by its load-indicating line, via a throttle 7 and a shuttle valve 14, to the pressure relief valve 4, which, via the control line 30, determines the pressure for actuating the differential pressure regulator 1 and sets the system pressure at, for example, P III = 200 bar. The consumers V II and V I are jointly connected by their respective loadindicating line 17 and 18 respectively, via a throttle 10 and 8 respectively and a common shuttle valve 16, to a pressure relief valve 5 which limits their maximum pressure to, for example, P I = 175 bar, the maximum pressure P II of consumer V II being limited in a manner to be explained later to below that of consumer V I, for which purpose a continuously variable 2/2-way control valve 6 is used.
For supplying as a matter of priority consumer V I (steering) and consumer V II (brake), the hydraulic control circuit has two priority valves 12 and 13, which are connected in series and are in each case formed by continuously variable 3/2-way valves. At the upstream, first priority valve 12, the system volumetric flow supplied by the pump 20 is divided into a supply line 19 leading to consumer V III and, preferably, into a supply line 21, referred to below as priority line, the pressure of which has a retroaction on the priority valve 12 against the spring prestress of the valve via a control line 22. The first priority valve 12 is springprestressed into the position shown and controlled on the spring side by the load-indicating lines 17, 18, the maximum pressure of which is limited by the pressure relief valve 5.
The priority line 21 carries a common preferential flow for consumer V I and consumer V II to the second, downstream priority valve 13. At this priority valve, this preferential flow is divided into a volumetric flow leading to consumer V II and, preferably, into a steering circuit flow, for which purpose the respective supply lines 23 and 24 are used. This priority valve is spring-prestressed into the position illustrated. Via the further control line 25, the steering circuit pressure prevailing in the supply line 24 acts on the tubular slide of the second priority valve 13, counter to the spring prestress, as a result of which, if the steering circuit is provided with a suffi cient supply, an immediate pressurization of the supply line 23 to consumer V II is guaranteed. Furthermore, the second priority valve 13 is controlled on its spring side via the control valve 6, one connection of which acts via the control line 26 on the tubular slide of the priority valve 13 and the other connection of which leads to the supply line 24. The control valve 6 is furthermore actuated via the control line 27 by the load-indicating line 17 of the second consumer V II, while the loadindicating line 18 is connected via a throttle 9 to the control line 26.
It is evident from the above that the downstream priority valve 13 no longer has to be designed for the full pump delivery flow of, for example, 150 1/min - but only for the preferential volumetric flow which consumer V I and consumer V II, i.e. for example the steering circuit and the brake circuit, require. Consumer V III. at all times receives only the residual volumetric flow. In addition, the control valve 6 makes it possible to limit the maximum pressure of consumer V II to below the maximum pressure of consumer V I, e.g. to P II = 150 bar.
If the pressure in the load-indicating line 17 reaches the value set by the spring prestress of the control valve 6, the control sides of the priority valve 13 are connected to one another to such an extent that this valve only allows the volumetric flow to consumer V II which is required in order to maintain the maximum pressure set in the load- indicating line 17 by the control valve 6.
By means of the pressure relief valves 4 and 5 and the control valve 6, the maximum pressure to the individual consumers is limited in the following order:
P III > P I > P II Consumer V I is supplied with the highest priority, consumer V II is in second position and consumer V III is supplied with the lowest priority.

Claims (7)

CLAIMS:
1. A hydraulic control circuit f or a motor vehicle f or one or more consumers to be supplied as a matter of priority, such as for example f or a brake valve supplied via a priority valve by a pump which is simultaneousl: used for supplying at least one secondary consumer and one further consumer, e.g. the steering circuit, said circuit comprising two priority valves connected in series, of which the upstream priority valve supplies at least one secondary consumer and divides off a common preferential flow for two further consumers to the downstream priority valve for supplying as a matter of priority the first of said two further consumers wherein the maximum pressures of the secondary consumer and of the first further consumer are in each case limited by a respective pressure relief valve, and the maximum pressure of the second further consumer is limited to below that of the first further consumer by the downstream priority valve, being controlled on both sides by pressure in the supply line to the first further consumer, the pressure on the spring side of the downstream priority valve being increased via a control line by a control valve in order to bring the priority valve into a throttling position for the supply line to the second further consumer, which, via a load-indicating line thereof, controls the control valve.
2. A hydraulic control circuit according to claim 1, wherein the secondary consumer is connected via a load-indicating line and a throttle to said pressure -relief valve therefor which limits the system pressure and the first further consumer is connected via a. throttle to said pressure relief valve therefor which determines the control pressure on the spring side of the downstream priority valve, the other side of which is controlled by the pressure in the supply line to the downstream priority valve.
3. A hydraulic control circuit according to claim 2, wherein a pump is connected to the downstream priority valve via a differential pressure regulator controlled by the load-indicating line of the secondary consumer.
4. A hydraulic control circuit according to any one of the preceding claims, wherein between the control valve and the spring side of the downstream priority valve, the control line is connected via a throttle to the load-indicating line of the first further consumer.
5. A hydraulic control circuit according to any one of the preceding claims, wherein the maximum pressures of the individual consumers are set such that the maximum prssure of the secondary consumer is greater than that of the first further consumer which is greater than that of the second further consumer.
6. A hydraulic control arrangement for controlling hydraulic fluid supply to two consumers such that the supply to one has priority, the arrangement comprising a priority valvb with respective supply lines for supplying hydraulic fluid to the two consumers and having a slidab29 valve element on one end of which a spring force acts to bias the valve element in one direction, respective hydraulic lines for enabling hydraulic fluid at the pressure in the supply line to the consumer having priority to act on both ends of the slidable valve element, and a control valve in the hydraulic line associated with said one end of the valve element for controlling hydraulic fluid flow therein, the operation of which control valve is controlled by the pressure of the hydraulic fluid in a load indicating line of the other consumer.
7. A hydraulic control circuit substantially as herein described with reference to the accompanying drawing.
Pubhshed 1990 at The Patent Office. State House. 66 71 Hig) ' 7Holborn. London WC1R4TP Further copies maybe obtained from The -Patentoffim Sales Branch. St MaT7 Cray. Orpington. Kent ERB 3RD. Printed by Multiplex techniques ltd- St Mary Cray. Kent. Con 18-,
GB8917320A 1988-08-01 1989-07-28 Hydraulic control circuit for a motor vehicle Expired - Lifetime GB2224780B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19883826164 DE3826164A1 (en) 1988-08-01 1988-08-01 HYDRAULIC CONTROL CIRCUIT FOR A MOTOR VEHICLE FOR PRIORLY SUPPLYING ONE OR MORE CONSUMERS

Publications (3)

Publication Number Publication Date
GB8917320D0 GB8917320D0 (en) 1989-09-13
GB2224780A true GB2224780A (en) 1990-05-16
GB2224780B GB2224780B (en) 1992-08-26

Family

ID=6360052

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8917320A Expired - Lifetime GB2224780B (en) 1988-08-01 1989-07-28 Hydraulic control circuit for a motor vehicle

Country Status (2)

Country Link
DE (1) DE3826164A1 (en)
GB (1) GB2224780B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110252778A1 (en) * 2010-04-20 2011-10-20 Marcus Bitter Hydraulic system
CN110526140A (en) * 2019-09-16 2019-12-03 江苏建筑职业技术学院 Tyre crane auxiliary system and control method

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4020561A1 (en) * 1990-06-28 1992-01-09 Man Nutzfahrzeuge Ag COMPRESSED AIR SYSTEM IN A COMMERCIAL VEHICLE
DE4105144A1 (en) * 1991-02-20 1992-08-27 Teves Gmbh Alfred Six-piston radial pump - is driven by vehicle IC engine circuit providing power to servo steering, camshaft adjustment and wheel brakes
US5241821A (en) * 1991-04-08 1993-09-07 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Hydraulic system for a vehicle
DE4337210A1 (en) * 1993-10-30 1995-05-04 Rexroth Mannesmann Gmbh Central hydraulic installation for a motor vehicle
DE4337819A1 (en) * 1993-11-05 1995-05-11 Fichtel & Sachs Ag Hydraulic system for a motor vehicle
DE19536663A1 (en) * 1995-09-30 1997-04-03 Wabco Gmbh Device for controlling the pressure in pressure medium lines
DE19542275B4 (en) * 1995-11-13 2006-07-27 Bosch Rexroth Aktiengesellschaft Priority flow circuit
DE19703997A1 (en) 1997-02-04 1998-08-06 Mannesmann Rexroth Ag Hydraulic control circuit for a priority and for a subordinate hydraulic consumer
GB2324575B (en) * 1997-04-24 2000-08-09 Caterpillar Inc Load sense hydraulic system
DE10027734A1 (en) * 2000-06-03 2001-12-06 Hydraulik Ring Gmbh Hydraulic system for actuating at least two functional areas in a vehicle, preferably for steering and switching a motor vehicle
DE102011115805B4 (en) 2011-10-12 2021-12-09 Robert Bosch Gmbh Hydraulic system with a main pump and a charge pump
CN109236781B (en) * 2018-11-14 2023-07-21 浙江丰州精密制造有限公司 Time sequence valve

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3916932A (en) * 1974-03-28 1975-11-04 Eaton Corp Flow divider valve assembly
US4343151A (en) * 1980-05-16 1982-08-10 Caterpillar Tractor Co. Series - parallel selector for steering and implement
US4665695A (en) * 1981-03-13 1987-05-19 Trw Inc. Hydrostatic load sense steering system
DE3149026A1 (en) * 1981-12-11 1983-06-30 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen CONTROL DEVICE FOR TWO OVER ONE BRANCH HYDRAULIC ACTUATORS SUPPLIED BY A HIGH PRESSURE PUMP
DE3507122A1 (en) * 1985-02-28 1986-08-28 Mannesmann Rexroth GmbH, 8770 Lohr PRIORITY CONTROL FOR HYDRAULIC CONSUMERS

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110252778A1 (en) * 2010-04-20 2011-10-20 Marcus Bitter Hydraulic system
US9084388B2 (en) * 2010-04-20 2015-07-21 Deere & Company Hydraulic system
CN110526140A (en) * 2019-09-16 2019-12-03 江苏建筑职业技术学院 Tyre crane auxiliary system and control method

Also Published As

Publication number Publication date
GB8917320D0 (en) 1989-09-13
DE3826164A1 (en) 1990-02-08
GB2224780B (en) 1992-08-26
DE3826164C2 (en) 1990-09-06

Similar Documents

Publication Publication Date Title
GB2224780A (en) Hydraulic control circuit for a motor vehicle
US2892311A (en) Hydraulic apparatus
US6848255B2 (en) Hydraulic fan drive system
US4470260A (en) Open center load sensing hydraulic system
EP0044065A2 (en) Load sensing hydraulic system
EP1760325B1 (en) Hydraulic load sensing system for agricultural tractors
JPH045841B2 (en)
CA2219207A1 (en) Pressure compensating hydraulic control system
GB2199385A (en) Anti-skid apparatus for an automotive vehicle
EP0911529A3 (en) Hydraulic control valve system with non-shuttle pressure compensator
CA2255991A1 (en) Hydraulic control valve system with load sensing priority
EP1843047B1 (en) Hydraulic supply systems
KR960007217B1 (en) Hydraulic brake circuit for a motor vehicle equipment with a wheel antilock device
JPH05501600A (en) Load pressure replication circuit
US4665939A (en) Priority control for hydraulic consumers
US3212523A (en) Fluid system and relief valve assembly therefor
US20100187900A1 (en) Hydraulic power brake system
US4955444A (en) Hydrostatic steering device
CA1244742A (en) Pressure supply device for a hydraulic system
EP0020105B1 (en) Hydraulic braking system
GB2325446A (en) Vehicle hydraulic system
US5779324A (en) Towed vehicle brake system
US6029531A (en) Gear control system intended in particular for an electrically operated automatic transmission of layshaft design
US8006490B2 (en) Hydraulic control device
AU593458B2 (en) Method and apparatus for braking heavy vehicles

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19950728