EP0684388B1 - Système de commande hydraulique de détection de la charge - Google Patents

Système de commande hydraulique de détection de la charge Download PDF

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Publication number
EP0684388B1
EP0684388B1 EP95202288A EP95202288A EP0684388B1 EP 0684388 B1 EP0684388 B1 EP 0684388B1 EP 95202288 A EP95202288 A EP 95202288A EP 95202288 A EP95202288 A EP 95202288A EP 0684388 B1 EP0684388 B1 EP 0684388B1
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EP
European Patent Office
Prior art keywords
pressure
load
valve
actuator
valves
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 - Lifetime
Application number
EP95202288A
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German (de)
English (en)
Other versions
EP0684388A2 (fr
EP0684388A3 (fr
Inventor
Hideshi Koiwai
Hisato Naito
Yoshitake Yonekubo
Kenichi Nishiumi
Yoshimi Hasegawa
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KYB Corp
Original Assignee
Kayaba Industry Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP03357128A external-priority patent/JP3124094B2/ja
Priority claimed from JP21224492A external-priority patent/JPH0633904A/ja
Priority claimed from JP04250517A external-priority patent/JP3128775B2/ja
Application filed by Kayaba Industry Co Ltd filed Critical Kayaba Industry Co Ltd
Publication of EP0684388A2 publication Critical patent/EP0684388A2/fr
Publication of EP0684388A3 publication Critical patent/EP0684388A3/fr
Application granted granted Critical
Publication of EP0684388B1 publication Critical patent/EP0684388B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2232—Control of flow rate; Load sensing arrangements using one or more variable displacement pumps
    • 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
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
    • 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
    • F15B11/16—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
    • 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
    • F15B11/163—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for sharing the pump output equally amongst users or groups of users, e.g. using anti-saturation, pressure compensation
    • 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
    • F15B11/166—Controlling a pilot pressure in response to the load, i.e. supply to at least one user is regulated by adjusting either the system pilot pressure or one or more of the individual pilot command pressures
    • 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
    • F15B2211/25—Pressure 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
    • F15B2211/30555—Inlet and outlet of the pressure compensating valve being connected to the 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
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/329—Directional control characterised by the type of actuation actuated by fluid pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40576—Assemblies of multiple valves
    • F15B2211/40584—Assemblies of multiple valves the flow control means arranged in parallel with a check valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/46—Control of flow in the return line, i.e. meter-out control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/47—Flow control in one direction only
    • F15B2211/473—Flow control in one direction only without restriction in the reverse direction
    • 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
    • F15B2211/50518—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means 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
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5153—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/575—Pilot pressure control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—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
    • F15B2211/635—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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/65—Methods of control of the load sensing pressure
    • F15B2211/654—Methods of control of the load sensing pressure the load sensing pressure being lower than the 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders

Definitions

  • This invention relates to a load-sensing active hydraulic control device which is suitable for use for a power shovel or the like and includes a service port which permits a specific actuator as well as a main actuator constantly used to be connected thereto.
  • a known load-sensing active hydraulic control device generally comprises a variable discharge pump, a plurality of actuators provided with change-over valves, respectively, which are connected in parallel to each other with respect to the variable discharge pump, a variable orifice of which a degree of opening is controlled depending on the amount of changing-over of each of the change-over valves, pressure compensating valves each arranged on a downstream side of the variable orifice for keeping a pressure difference between a load pressure and a pressure on the downstream side of the variable orifice constant, a loading detecting passage for detecting a load pressure of each of the actuators, and shuttle valves each connected to the load detecting passage, whereby a maximum pressure selected by the shuttle valves is introduced into a regulator of the variable discharge pump to keep an output of the pump constant.
  • a load-sensing active hydraulic control device which is characterized in that the load detecting passage communicating directly with the shuttle valve positioned on the most downstream side is provided with an on-off valve which is closed when a pressure on an upstream side of the shuttle on the most downstream side is equal to or exceeds a set pressure.
  • the on-off valve when a pressure on the upstream side of the shuttle valve positioned on the most downstream side is equal to or exceeds a set pressure, the on-off valve is closed. Closing of the on-off valve prevents, even when a load pressure of the actuator connected to the shuttle valve on the most downstream side is increased, the load pressure from being introduced into the regulator of the variable discharge pump. Therefore, after the on-off valve is closed, the pressure compensating valve is caused to operate to exhibit a load-sensing function.
  • a conventional load-sensing active hydraulic control device includes a main actuator 20 connected to normal actuator ports 17a and 18a and a specific sub-actuator 19 connected to service ports 17b and 18b.
  • an actual power shovel includes in addition to the main actuator 20, a plurality of additional main actuators connected thereto, which are not shown in Figure 3 for the sake of brevity.
  • the conventional control device further includes a variable discharge pump 1 provided with a main passage 2 to which a change-over valve 4 of the main actuator 20 and a change-over valve 3 of the sub-actuator 19 are connected in parallel.
  • the change-over valves 3 and 4 are constructed in substantially the same manner, therefore, corresponding parts of the valves 4 and 3 are designated by like reference numerals.
  • pressure compensating valves 8 respectively connected to the valves 3 and 4 are constructed in substantially the same manner, therefore, corresponding parts of the pressure compensating valves 8 are designated by the same reference numerals.
  • the above-described change-over valves 3 and 4 are constructed into a seven-port and three-position structure. More particularly, the change-over valves 3 and 4 each include a first port 5 connected to the main passage 2, a second port 40, a third port 9 connected through the pressure compensating valve 8 to the second port 40, and a fourth port 41 connected to a return passage 12 connected to a tank T1.
  • the change-over valves 3 and 4 each include fifth and sixth ports 10 and 11 connected to the main actuator 20 or sub-actuator 19 through the actuator ports 17a and 18a or service ports 17b and 18b. Further, the change-over valves 3 and 4 each include a seventh port 13 connected to shuttle valves 30, 31 and 32.
  • the shuttle valves 30-32 are connected to all the change-over valves 3 and 4 one by one and adapted to select a high pressure from the change-over valves.
  • the shuttle valve 30 positioned on the right side in Figure 3 is defined as being an upstream side of the system.
  • reference character V designates a pilot valve, which functions to control a pilot pressure for changing over the change-over valve 4.
  • a control cylinder 16 and a valve 15 co-operate with each other to constitute a regulator. Also, changing-over of each of the change-over valves 3 and 4 causes communication of the first port 5 and a second port 40 and a degree of opening of each of the ports 5 and 40 is determined depending on the amount of changing-over of the change-over valves 4 and 3. The communication of the first and second ports 5 and 40 forms a variable orifice.
  • variable discharge pump 1 is adapted to control its tilting angle which is proportional to its discharge quantity depending on operation of the control cylinder 16.
  • the control cylinder 16 is controlled depending on a change-over position of the valve 15.
  • the valve 15 includes a first pilot chamber 15a connected to the shuttle valve 32 on the most downstream side and a second pilot chamber 15b connected to a discharge side of the variable discharge pump 1.
  • the valve 15 thus constructed is kept at a normal position shown in Figure 3 by the action of a spring 42.
  • the valve causes the control cylinder 16 to communicate with the tank T1 to keep the discharge quantity minimum when it is at the normal position.
  • valve 15 When a discharge pressure or the pump 1 is increased to cause a build up of a pressure at the pilot chamber 15b to overcome the pressure at the pilot chamber 15a and the spring 42, the valve 15 is changed over (i.e. moved down in Figure 3) to a position so that its upper side in Figure 3 is operative, thereby to introduce the discharge pressure of the pump into the control cylinder 16.
  • Such an action of the pressure on the control cylinder 16 causes the tilting angle of the variable discharge pump 1 to be reduced, resulting in the discharge quantity of the pump 1 being decreased.
  • changing-over of each of the change-over valves 3 and 4 to a left side position causes communication of the first and second ports 5 and 40 through the variable discharge orifice.
  • the degree of opening of the orifices, and hence of the communication depends on the amount of changing-over of each of the change-over valves 3 and 4.
  • ports 5 and 40 Such communication between ports 5 and 40 causes hydraulic fluid to flow from the main passage 2 through the pressure compensating valves 8 (which are moved to the right) and then through the third port 9 to the fifth port 10. Also, on the side of the main actuator 20, the hydraulic fluid thus flowing to the fifth port 10 is then fed through the actuator port 17a to the main actuator 20. At this time, the fifth port 10 is caused to communicate with the seventh port 13 as well, so that a load pressure of the main actuator 20 is introduced through the seventh port 13 into the shuttle valve 31.
  • the shuttle valve 31 compares the load pressure of the main actuator 20 with a load pressure selected by the shuttle valve 30 positioned on an upstream side of the shuttle valve 31, selecting higher one of both load pressures, which is then introduced into the shuttle valve 32 positioned on a downstream side of the shuttle valve 31.
  • the shuttle valve 32 connected to the seventh port 13 of the change-over valve 3 on the side of the sub-actuator 19 is positioned on the most downstream side of the system, so that a maximum pressure of the system selected by the shuttle valve 32 is introduced into the pilot chamber 15a of the valve 15 functioning to control the tilting angle and hence the output of the variable discharge pump 1.
  • the maximum pressure of the system and the discharge pressure of the variable discharge pump 1 are compared with each other to cause the discharge pressure of the variable discharge pump 1 to be kept increased in an amount of ⁇ corresponding to elastic force of the spring 42 as compared with the maximum pressure of the system. Also, the variable discharge pump 1 is controlled in such a manner that the power thereof is kept constant.
  • the sub-actuator 19 is connected to the service ports 17b and 18b may typically comprise a breaker or scissors in the case of a shovel.
  • the conventional control device constructed as described above exhibits the following disadvantages, for example, when a required maximum pressure or the sub-actuator 19 connected to the service ports 17b and 18b is lower than a required maximum pressure of the main actuator 20.
  • the load pressure on the side of the sub-actuator 19 is increased to a level exceeding the required maximum pressure.
  • the load pressure on the side of the sub-actuator 19 is caused to increase to a set maximum pressure of the system or the required maximum pressure of the main actuator 20.
  • a load detecting passage 33 through which the seventh port 13 of the change-over valve 3 is connected to the shuttle valve 32 is provided with an on-off valve 34.
  • the on-off valve 34 is kept an open position shown in Figure 1 by an action of a spring 35 and changed over to a closed position when a pilot pressure acting on a pilot chamber 34a overcomes elastic force of the spring 35.
  • the pilot chamber 34a is connected through a passage 43 to an upstream side of the shuttle valve 32.
  • P F is equal to or below P sp (P F ⁇ P sp )
  • the on-off valve 34 is kept open, so that the pressures P f and P F are compared with each other in the shuttle valve 32, resulting in higher one of the pressures P f and P F being selected, which is then fed back to the regulator.
  • a maximum value of a load pressure of each of all the actuators is selected.
  • a pressure fed back to the regulator depends on the pressure P F on the upstream side of the shuttle valve 32 irrespective of a value of the load pressure P f of the sub-actuator 19.
  • the load pressure P f of the sub-actuator 19 is P F + ⁇ which is a discharge pressure of the pump or is fixed to a load pressure of the sub-actuator 19 which is a pressure within the discharge pressure of the pump 1.
  • a pressure compensating valve 8 functions to carry out load-sensing control.
  • the load-sensing active hydraulic control device of the present invention effectively prevents excessive consumption of energy when an additional actuator is used at a pressure lower than a maximum circuit pressure of the system, resulting in improving economical efficiency.

Claims (1)

  1. Dispositif de commande hydraulique active de détection d'une charge, comprenant une pluralité d'actionneurs équipés respectivement de soupapes de commutation (3, 4), une pompe à refoulement variable (1), lesdites soupapes de commutation (3, 4) étant branchées en parallèle par rapport à la pompe à refoulement variable (1), et possédant un orifice variable, dont le degré d'ouverture est commandé en fonction de la quantité de commutation de chacune des soupapes de commutation, des soupapes de compensation de pression (8) disposées chacune sur un côté aval de l'orifice variable pour maintenir constante une différence de pression entre une pression de charge et une pression présente sur le côté aval de l'orifice variable, un passage (33, 33a) de détection de la charge servant à détecter une pression de charge de chacun des actionneurs, et des soupapes à alternance (30, 31, 32) raccordées chacune au passage (33) de détection de la charge, ce qui a pour effet qu'une pression maximale sélectionnée par les soupapes à alternance est introduite dans un régulateur de la pompe à refoulement variable de manière à maintenir constante un débit de sortie de la pompe caractérisé en ce que le passage (33) de détection de la charge, qui communique directement avec la soupape à alternance (32) disposée sur le côté le plus en aval, est pourvu d'une soupape marche-arrêt (34), qui est fermée lorsqu'une pression sur le côté amont de la soupape à alternance (32) sur le côté le plus en aval est égale ou dépasse une pression de consigne.
EP95202288A 1991-12-25 1992-12-23 Système de commande hydraulique de détection de la charge Expired - Lifetime EP0684388B1 (fr)

Applications Claiming Priority (7)

Application Number Priority Date Filing Date Title
JP357128/91 1991-12-25
JP03357128A JP3124094B2 (ja) 1991-12-25 1991-12-25 複数アクチュエータの制御装置
JP21224492A JPH0633904A (ja) 1992-07-16 1992-07-16 負荷感応形制御装置
JP212244/92 1992-07-16
JP250517/92 1992-08-26
JP04250517A JP3128775B2 (ja) 1992-08-26 1992-08-26 負荷感応形制御装置
EP19920311770 EP0550257B1 (fr) 1991-12-25 1992-12-23 Dispositif de commande pour plusieurs servomoteurs

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
EP92311770.9 Division 1992-12-23
EP19920311770 Division EP0550257B1 (fr) 1991-12-25 1992-12-23 Dispositif de commande pour plusieurs servomoteurs

Publications (3)

Publication Number Publication Date
EP0684388A2 EP0684388A2 (fr) 1995-11-29
EP0684388A3 EP0684388A3 (fr) 1996-11-06
EP0684388B1 true EP0684388B1 (fr) 1999-02-24

Family

ID=27329339

Family Applications (4)

Application Number Title Priority Date Filing Date
EP19920311770 Expired - Lifetime EP0550257B1 (fr) 1991-12-25 1992-12-23 Dispositif de commande pour plusieurs servomoteurs
EP95202288A Expired - Lifetime EP0684388B1 (fr) 1991-12-25 1992-12-23 Système de commande hydraulique de détection de la charge
EP95202286A Expired - Lifetime EP0684387B1 (fr) 1991-12-25 1992-12-23 Système de commande hydraulique de détection de la charge
EP95202287A Expired - Lifetime EP0684389B1 (fr) 1991-12-25 1992-12-23 Système de commande pour appareil hydraulique avec plusieurs consommateurs

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP19920311770 Expired - Lifetime EP0550257B1 (fr) 1991-12-25 1992-12-23 Dispositif de commande pour plusieurs servomoteurs

Family Applications After (2)

Application Number Title Priority Date Filing Date
EP95202286A Expired - Lifetime EP0684387B1 (fr) 1991-12-25 1992-12-23 Système de commande hydraulique de détection de la charge
EP95202287A Expired - Lifetime EP0684389B1 (fr) 1991-12-25 1992-12-23 Système de commande pour appareil hydraulique avec plusieurs consommateurs

Country Status (2)

Country Link
EP (4) EP0550257B1 (fr)
DE (4) DE69229968T2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19831595B4 (de) * 1998-07-14 2007-02-01 Bosch Rexroth Aktiengesellschaft Hydraulische Schaltung

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19719228A1 (de) * 1997-05-07 1998-11-12 Bosch Gmbh Robert Hydraulische Steuereinrichtung zur lastdruckunabhängigen Steuerung eines doppeltwirkenden Motors
FR2807118B1 (fr) * 2000-03-28 2002-07-05 Mannesmann Rexroth Sa Circuit hydraulique pour l'actionnement de recepteurs hydrauliques multiples
CN103221617B (zh) * 2010-11-01 2015-09-16 沃尔沃建筑设备公司 用于控制工程机械的液压系统的方法
CN104627880B (zh) * 2014-12-31 2017-02-22 中联重科股份有限公司 闭式系统、控制方法、卷扬系统和履带式车辆行走系统
CN110671376B (zh) * 2019-09-29 2021-03-12 中国矿业大学 工程机械负载敏感-进出口独立液压系统及其控制方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3710699C1 (de) * 1987-03-31 1988-08-18 Heilmeier & Weinlein Hydraulische Steuervorrichtung fuer eine Verbrauchergruppe
SE8803181D0 (sv) * 1988-09-09 1988-09-09 Atlas Copco Ab Hydraulic driving system with a priority function for hydraulic motors
DE69025462T2 (de) * 1989-05-24 1996-09-26 Komatsu Mfg Co Ltd Hydraulische schaltungsvorrichtung

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19831595B4 (de) * 1998-07-14 2007-02-01 Bosch Rexroth Aktiengesellschaft Hydraulische Schaltung

Also Published As

Publication number Publication date
EP0684389B1 (fr) 1999-09-08
DE69228489T2 (de) 1999-09-30
EP0684389A2 (fr) 1995-11-29
DE69229966T2 (de) 2000-03-09
EP0684387A2 (fr) 1995-11-29
DE69228489D1 (de) 1999-04-01
EP0684389A3 (fr) 1996-10-30
EP0550257B1 (fr) 1998-05-06
DE69229968T2 (de) 2000-03-09
EP0684387A3 (fr) 1996-10-30
DE69225392T2 (de) 1998-09-03
EP0684388A2 (fr) 1995-11-29
DE69229966D1 (de) 1999-10-14
DE69229968D1 (de) 1999-10-14
EP0550257A1 (fr) 1993-07-07
EP0684388A3 (fr) 1996-11-06
DE69225392D1 (de) 1998-06-10
EP0684387B1 (fr) 1999-09-08

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