WO2013114980A1 - 流体圧制御装置 - Google Patents
流体圧制御装置 Download PDFInfo
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- WO2013114980A1 WO2013114980A1 PCT/JP2013/050981 JP2013050981W WO2013114980A1 WO 2013114980 A1 WO2013114980 A1 WO 2013114980A1 JP 2013050981 W JP2013050981 W JP 2013050981W WO 2013114980 A1 WO2013114980 A1 WO 2013114980A1
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- WIPO (PCT)
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- pressure
- valve
- pilot
- pressure chamber
- control device
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- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01B—SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
- A01B63/00—Lifting or adjusting devices or arrangements for agricultural machines or implements
- A01B63/02—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors
- A01B63/10—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors operated by hydraulic or pneumatic means
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- 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
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/08—Characterised by the construction of the motor unit
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- 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
- F15B11/003—Systems with load-holding valves
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- 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
- F15B11/006—Hydraulic "Wheatstone bridge" circuits, i.e. with four nodes, P-A-T-B, and on-off or proportional valves in each link
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
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- 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
- F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
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- 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
- F15B13/028—Shuttle valves
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- 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
- F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
- F15B13/0422—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with manually-operated pilot valves, e.g. joysticks
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- 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
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
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- 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
- F15B2211/30515—Load holding valves
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- 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
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- 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
- F15B2211/30575—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 in a Wheatstone Bridge arrangement (also half bridges)
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- 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
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- 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
- F15B2211/35—Directional control combined with flow control
- F15B2211/351—Flow control by regulating means in feed line, i.e. meter-in control
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- 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
- F15B2211/35—Directional control combined with flow control
- F15B2211/353—Flow control by regulating means in return line, i.e. meter-out control
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- 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
- F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
- F15B2211/7051—Linear output members
- F15B2211/7052—Single-acting output members
Definitions
- the present invention relates to a fluid pressure control device for controlling fluid pressure work equipment such as a tractor.
- a fluid pressure control device that drives an actuator using a working fluid discharged from a fluid pressure pump is used in a fluid pressure working device such as a tractor.
- JP08-261206A discloses a hydraulic control device that controls the lifting and lowering of a lift cylinder of an agricultural tractor.
- the hydraulic control device includes an ascending valve provided between the hydraulic pump and the lift cylinder and controlled by an adjustment valve, a descending proportional solenoid valve provided between the lift cylinder and the tank, and the lifting cylinder and the descending valve.
- a check valve provided between the proportional solenoid valve and controlled to be opened and closed by a pilot valve.
- the present invention has been made in view of the above-described problems, and an object thereof is to simplify the configuration of a fluid pressure control device that controls a fluid pressure working device.
- a fluid pressure control device capable of driving a load by extending and contracting a cylinder by a working fluid supplied from a pump, wherein the cylinder is in a state where supply and discharge of the working fluid is blocked.
- the operation check valve that shuts off the discharge of the working fluid from the engine and the second control valve are pilot operated with a pilot pressure, and the operation check valve is opened with the pilot pressure.
- a pilot valve changing Ri, fluid pressure control device comprising a provided.
- FIG. 1 is a configuration diagram of a tractor to which a fluid pressure control device according to an embodiment of the present invention is applied.
- FIG. 2 is a fluid pressure circuit diagram of the fluid pressure control apparatus according to the embodiment of the present invention.
- the hydraulic control device 100 controls the operation of a fluid pressure work device such as a tractor.
- hydraulic oil is used as the working fluid.
- the tractor 1 includes a tank 9 in which hydraulic oil is stored, a pump 10 that discharges hydraulic oil sucked from the tank 9, a cylinder 3 that expands and contracts by hydraulic oil from the pump 10, and a cylinder 3
- the working machine 2 as a load that moves up and down according to the expansion and contraction of the cylinder 3 and a hydraulic control device 100 that controls the expansion and contraction operation of the cylinder 3 are provided.
- the work machine 2 is provided at the rear part of the tractor 1 so as to be replaceable.
- the work machine 2 moves up and down when the expansion and contraction motion of the cylinder 3 is transmitted via the link mechanism 2a.
- a leveler or the like for leveling the ground may be attached as the work machine 2 instead of the rotary to which a plurality of claws for tillage operation as shown in FIG.
- the pump 10 is a gear pump that is rotationally driven by the engine 8.
- the engine 8 that drives the pump 10 is the same as the engine that drives the wheels of the tractor 1.
- the pump 10 is always driven to rotate when the engine 8 is in an operating state.
- the cylinder 3 is a ram cylinder fixed to the main body of the tractor 1.
- the cylinder 3 includes a piston rod 4 that is connected to the work machine 2 via a link mechanism 2a and moves the work machine 2 up and down.
- both the rod-side pressure chamber 6 and the piston-side pressure chamber 7 correspond to pressure chambers.
- a pair of cylinders 3 is provided in the present embodiment, but may be single when the load is relatively small.
- the hydraulic control device 100 controls the expansion and contraction of the cylinder 3 with hydraulic oil supplied from the pump 10 to drive the working machine 2 up and down.
- the hydraulic control device 100 discharges hydraulic oil discharged from the pump 10 to the piston-side pressure chamber 7 when the cylinder 3 is extended, and is discharged from the piston-side pressure chamber 7 when the cylinder 3 is contracted. And a discharge passage 42 for guiding the hydraulic oil to the tank 9.
- the hydraulic control device 100 switches the piston-side pressure chamber 7 so that hydraulic oil is supplied and controls the extension operation of the cylinder 3 and pilot-operates the first control valve 11 with the pilot pressure.
- the first pilot valve 12, the check valve 13 that allows only the hydraulic oil supplied from the pump 10 to the piston-side pressure chamber 7, and the pump when the differential pressure across the first control valve 11 rises to the set pressure.
- an unload valve 14 for guiding the hydraulic oil discharged from the tank 10 to the tank 9.
- the first control valve 11, the check valve 13, and the unload valve 14 are interposed in the supply passage 41.
- the first control valve 11 has a supply position 11 a through which the hydraulic oil from the pump 10 can pass, and a cutoff position 11 b that shuts off the hydraulic oil from the pump 10 and guides the downstream hydraulic oil to the tank 9.
- the first control valve 11 includes an adjustment spring 11c that can adjust the urging force and a pilot portion 11d to which the pilot pressure from the first pilot valve 12 is guided.
- the first control valve 11 is switched to the cutoff position 11b by the urging force of the adjustment spring 11c when the pilot pressure is not guided from the first pilot valve 12 to the pilot portion 11d (state shown in the figure).
- the first control valve 11 is a proportional valve that can adjust the opening of the supply passage 41 steplessly in accordance with the magnitude of the pilot pressure guided to the pilot section 11d.
- the first pilot valve 12 is an electromagnetic valve that is switched based on an operation of an operation lever (not shown) by a user.
- the first pilot valve 12 branches from the supply passage 41 and supplies the hydraulic oil in the high pressure passage 44 to which the discharge pressure of the pump 10 is guided to the pilot portion 11d of the first control valve 11 and the operation of the high pressure passage 44. And a shutoff position 12b for shutting off the oil and guiding the hydraulic oil led to the pilot portion 11d to the tank 9.
- the first pilot valve 12 is switched to the cutoff position 12b by the urging force of the spring 12c when the operation lever is not operated by the user (the state shown in the figure).
- the first pilot valve 12 can steplessly adjust the magnitude of the pilot pressure guided to the pilot portion 11d according to the operation amount of the operation lever by the user.
- the check valve 13 is a load check valve interposed between the first control valve 11 and the piston side pressure chamber 7.
- the check valve 13 is closed by the urging force of the spring 13a because the upstream hydraulic oil is guided to the tank 9.
- the check valve 13 is pushed open by the high-pressure hydraulic oil discharged from the pump 10 and is opened.
- the unload valve 14 is interposed between the pump 10 and the first control valve 11.
- the unload valve 14 is operated from the pump 10 by introducing the hydraulic oil pressure between the first control valve 11 and the check valve 13 as a pilot pressure.
- the oil is switched so as to be guided to the cylinder 3.
- the unload valve 14 is switched so that the hydraulic oil discharged from the pump 10 is unloaded to the tank 9 when the first control valve 11 is in the shut-off position 11b.
- the pressure of hydraulic oil in the supply passage 41 upstream of the first control valve 11 is guided to the unload valve 14 as a pilot pressure, and on the other hand, the pressure of hydraulic oil in the supply passage 41 downstream of the first control valve 11. Is introduced as pilot pressure through the orifice 14a.
- the unload valve 14 is a pressure compensation valve that unloads hydraulic oil from the pump 10 to the tank 9 when the differential pressure between the upstream and downstream of the first control valve 11 exceeds a set pressure.
- the hydraulic control device 100 selects one of the hydraulic oil pressure supplied from the pump 10 and the hydraulic oil pressure in the piston-side pressure chamber 7 of the cylinder 3 and introduces it to the second pilot valve 22.
- a shuttle valve 45 for switching is provided.
- the hydraulic oil of the cylinder 3 is guided to one input port of the shuttle valve 45 through the high pressure passage 43 branched from the supply passage 41. Hydraulic fluid is guided from the high pressure passage 44 through the pilot passage 46 to the other input port of the shuttle valve 45.
- the hydraulic control device 100 performs pilot operation of the second control valve 21 that controls the contraction operation of the cylinder 3 by switching so that the hydraulic oil in the piston-side pressure chamber 7 is discharged, and pilot pressure.
- An operation check valve that is interposed between the second pilot valve 22 and the piston-side pressure chamber 7 and the second control valve 21 and shuts off the discharge of hydraulic oil from the piston-side pressure chamber 7 when switched to the closed state. 30.
- the second control valve 21 and the operation check valve 30 are interposed in the discharge passage 42.
- the second control valve 21 has a discharge position 21a through which hydraulic oil from the piston-side pressure chamber 7 can pass, and a blocking position 21b through which hydraulic oil from the piston-side pressure chamber 7 cannot pass.
- the second control valve 21 includes an adjustment spring 21c that can adjust the urging force and a pilot portion 21d to which the pilot pressure from the second pilot valve 22 is guided.
- the second control valve 21 is switched to the cutoff position 21b by the urging force of the adjustment spring 21c when the pilot pressure is not guided from the second pilot valve 22 to the pilot portion 21d (state shown in the drawing).
- the second control valve 21 is a proportional valve that can adjust the opening degree of the discharge passage 42 in a stepless manner in accordance with the magnitude of the pilot pressure guided to the pilot portion 21d.
- the second control valve 21 is a spool valve that is opened and closed as a spool (not shown) moves. Therefore, even when the second control valve 21 is switched to the cutoff position 21b, the hydraulic oil in the discharge passage 42 may leak from the pilot portion 21d. Therefore, an operation check valve 30 is provided upstream of the second control valve 21 to completely shut off the hydraulic oil in the discharge passage 42.
- the second pilot valve 22 is an electromagnetic valve that is switched based on an operation of an operation lever (not shown) by a user.
- the second pilot valve 22 shuts off the hydraulic fluid guided from the shuttle valve 45 and tanks the downstream hydraulic fluid while supplying the hydraulic fluid guided from the shuttle valve 45 to the pilot portion 21d of the second control valve 21. 9 and a blocking position 22b leading to 9.
- the second pilot valve 22 is switched to the cutoff position 22b by the urging force of the spring 22c when the operation lever is not operated by the user (the state shown in the figure).
- the second pilot valve 22 can steplessly adjust the magnitude of the pilot pressure guided to the pilot portion 21d according to the operation amount of the operation lever.
- the pilot pressure introduced through the second pilot valve 22 was selected by the shuttle valve 45 among the pressure of the hydraulic oil supplied from the pump 10 and the pressure of the hydraulic oil in the piston-side pressure chamber 7 of the cylinder 3. This is the higher pressure.
- the operation check valve 30 is a check valve that is opened by the pilot pressure from the second pilot valve 22 that pilot-operates the second control valve 21.
- the operation check valve 30 is provided immediately downstream of the piston side pressure chamber 7 of the cylinder 3. As a result, the operation check valve 30 can block the discharge of the hydraulic oil from the piston-side pressure chamber 7 when switched to the closed state.
- the operation check valve 30 includes a valve body 31 that shuts off the discharge of hydraulic oil from the piston-side pressure chamber 7 when switched to the closed state, a spool 32 that faces the back surface of the valve body 31, A back pressure chamber 33 defined between one end and the back surface of the valve body 31 and a switching pressure chamber 34 defined to face the other end of the spool 32 and through which the pilot pressure is guided via the second pilot valve 22.
- the pressure of the hydraulic oil in the discharge passage 42 acts on the front surface of the valve body 31.
- the valve body 31 is formed with an orifice 31 a as a throttle that constantly guides the hydraulic oil in the discharge passage 42 to the back pressure chamber 33. As a result, the pressure of the hydraulic oil guided from the discharge passage 42 through the orifice 31 a acts on the back surface of the valve body 31.
- the working fluid from the piston side pressure chamber 7 flows into the back pressure chamber 33 through the orifice 31a.
- a spring 33a that urges the valve body 31 in the valve closing direction is accommodated.
- the pressure of the back pressure chamber 33 and the biasing force of the spring 33a act so that the valve body 31 is seated on the valve seat.
- the operation check valve 30 functions as a check valve that blocks the flow of hydraulic oil from the piston-side pressure chamber 7 to the tank 9. As a result, the hydraulic fluid in the piston-side pressure chamber 7 is prevented from leaking and the load pressure is maintained. Therefore, the stopped state of the piston rod 4 and the work machine 2 is maintained.
- the spool 32 is movable by a pilot pressure guided to the switching pressure chamber 34 via the second pilot valve 22.
- the spool 32 has a poppet valve 32a that seals the back pressure chamber 33 while being seated on the valve seat.
- the spool 32 moves in a direction to close the poppet valve 32 a by the pressure of the hydraulic oil in the back pressure chamber 33.
- the spool 32 moves in a direction to open the poppet valve 32 a by the pressure in the switching pressure chamber 34.
- the spool 32 is formed such that the pressure receiving area of the surface facing the switching pressure chamber 34 is larger than the pressure receiving area of the surface facing the back pressure chamber 33. Therefore, when the pressure of the hydraulic oil in the back pressure chamber 33 and the switching pressure chamber 34 is the same, the spool 32 moves in the direction in which the poppet valve 32a is opened due to the difference in pressure receiving area.
- the pilot pressure is guided to the switching pressure chamber 34 via the second pilot valve 22.
- the valve body 31 moves the spool 32 and opens the poppet valve 32a, and the hydraulic oil in the back pressure chamber 33 is discharged to the tank 9. Is switched to the open state.
- This set pressure is set to a low pressure compared to the pressure at which the pilot operation of the second control valve 21 is started.
- the user When raising the work machine 2, the user operates the operation lever to switch the first pilot valve 12 to the supply position 12a. Thereby, the pilot pressure is guided to the pilot portion 11d of the first control valve 11.
- the first control valve 11 is switched to the supply position 11a when the pilot pressure guided to the pilot portion 11d overcomes the urging force of the adjustment spring 11c. At this time, the opening degree of the first pilot valve 12 and the opening degree of the first control valve 11 are adjusted steplessly based on the operation amount of the operation lever by the user.
- the hydraulic oil that has passed through the first control valve 11 overcomes the urging force of the spring 13 a of the check valve 13 and is supplied to the piston-side pressure chamber 7 of the cylinder 3 through the supply passage 41.
- the piston 5 moves in the direction in which the piston rod 4 retracts due to the pressure receiving area difference between the rod-side pressure chamber 6 and the piston-side pressure chamber 7. Therefore, the cylinder 3 extends and the work implement 2 rises.
- the check valve 13 is in a closed state. Since the second pilot valve 22 is not operated by the user, the operation check valve 30 is also closed. Therefore, the hydraulic oil in the piston side pressure chamber 7 of the cylinder 3 is not discharged from anywhere. Therefore, the cylinder 3 maintains a constant length, and the work machine 2 is maintained at a constant height.
- the user When lowering the work machine 2, the user operates the operation lever to switch the second pilot valve 22 to the supply position 22a. As a result, the pilot pressure is guided to the switching pressure chamber 34 of the operation check valve 30 and the pilot portion 21 d of the second control valve 21.
- the operation check valve 30 moves the spool 32 to open the poppet valve 32a, discharges the hydraulic oil in the back pressure chamber 33, and releases the valve body. 31 is switched to the open state. As a result, the hydraulic oil in the piston-side pressure chamber 7 of the cylinder 3 passes through the operation check valve 30 and is guided to the second control valve 21.
- the second control valve 21 is switched to the discharge position 21a when the pilot pressure guided to the pilot portion 21d overcomes the urging force of the adjustment spring 21c.
- the second control valve 21 is switched to the discharge position 21a after the operation check valve 30 is opened. At this time, the opening degree of the second pilot valve 22 and the opening degree of the second control valve 21 are adjusted steplessly based on the operation amount of the operation lever by the user.
- the operation check valve 30 is opened to release the blocking of the discharge passage 42, so that the work implement 2 can be lowered. Then, by adjusting the opening degree of the discharge passage 42 by the second control valve 21, the work implement 2 is lowered while adjusting the lowering speed.
- the operation check valve 30 is opened by the pilot pressure of the second pilot valve 22 that pilot-operates the second control valve 21. Therefore, it is not necessary to separately provide a solenoid valve for opening the operation check valve 30. Therefore, the configuration of the hydraulic control device 100 that controls the tractor 1 can be simplified, and the cost of the hydraulic control device 100 can be reduced.
- the unload valve 14 is switched so as to unload the hydraulic oil in the same manner as when the work machine 2 is maintained at a constant height. Therefore, the hydraulic oil discharged from the pump 10 is prevented from increasing the pressure of the hydraulic oil in the supply passage 41 more than necessary.
- the operation check valve 30 is opened by the pilot pressure of the second pilot valve 22 that pilot-operates the second control valve 21, it is not necessary to separately provide a solenoid valve for opening the operation check valve 30. Therefore, the configuration of the hydraulic control device 100 that controls the tractor 1 can be simplified, and the cost of the hydraulic control device 100 can be reduced.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Soil Sciences (AREA)
- Environmental Sciences (AREA)
- Fluid-Pressure Circuits (AREA)
- Lifting Devices For Agricultural Implements (AREA)
Abstract
Description
Claims (5)
- ポンプから供給される作動流体によってシリンダを伸縮させて負荷を駆動可能な流体圧制御装置であって、
前記シリンダは、作動流体の給排が遮断された状態で前記負荷による負荷圧が作用する圧力室を有し、
前記圧力室に作動流体が供給されるように切り換わって前記シリンダの伸長動作を制御する第一制御弁と、
前記圧力室の作動流体が排出されるように切り換わって前記シリンダの収縮動作を制御する第二制御弁と、
前記圧力室と前記第二制御弁との間に介装され、閉状態に切り換えられた場合に前記圧力室からの作動流体の排出を遮断するオペレートチェック弁と、
前記第二制御弁をパイロット圧によってパイロット操作するとともに、当該パイロット圧によって前記オペレートチェック弁を開状態に切り換えるパイロット弁と、を備える流体圧制御装置。 - 請求項1に記載の流体圧制御装置であって、
前記第一制御弁と前記圧力室との間に介装され、前記ポンプから前記圧力室に供給される作動流体の通過のみを許容するチェック弁を更に備える流体圧制御装置。 - 請求項1に記載の流体圧制御装置であって、
前記オペレートチェック弁は、
閉状態に切り換えられた場合に前記圧力室からの作動流体の排出を遮断する弁体と、
前記弁体の背面に臨んで設けられ、前記パイロット弁を介して導かれるパイロット圧によって移動可能なスプールと、
前記スプールの一端と前記弁体の背面との間に画成され、前記圧力室からの作動流体が前記弁体に形成された絞りを通じて導かれる背圧室と、
前記スプールの他端に臨んで画成され、前記パイロット弁を介してパイロット圧が導かれる切換圧力室と、を備え、
前記弁体は、前記切換圧力室に導かれたパイロット圧が設定圧力を超えた場合に、前記スプールが移動して前記背圧室の作動流体が排出されることで開状態に切り換えられる流体圧制御装置。 - 請求項3に記載の流体圧制御装置であって、
前記設定圧力は、前記第二制御弁のパイロット操作が開始される圧力と比較して低圧に設定される流体圧制御装置。 - 請求項1に記載の流体圧制御装置であって、
前記パイロット弁を介して導かれるパイロット圧として、前記ポンプから供給される作動流体の圧力と、前記圧力室の作動油の圧力とのうちいずれか高圧の方を選択するシャトル弁を更に備える流体圧制御装置。
Priority Applications (4)
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EP13743398.3A EP2778435A4 (en) | 2012-02-03 | 2013-01-18 | DEVICE FOR REGULATING FLUID PRESSURE |
CN201380004205.0A CN103987970B (zh) | 2012-02-03 | 2013-01-18 | 流体压控制装置 |
KR1020147015986A KR101647571B1 (ko) | 2012-02-03 | 2013-01-18 | 유체압 제어 장치 |
US14/370,958 US9683587B2 (en) | 2012-02-03 | 2013-01-18 | Fluid pressure control device |
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JP2012-021993 | 2012-02-03 | ||
JP2012021993A JP5860711B2 (ja) | 2012-02-03 | 2012-02-03 | 流体圧制御装置 |
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WO2013114980A1 true WO2013114980A1 (ja) | 2013-08-08 |
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US (1) | US9683587B2 (ja) |
EP (1) | EP2778435A4 (ja) |
JP (1) | JP5860711B2 (ja) |
KR (1) | KR101647571B1 (ja) |
CN (1) | CN103987970B (ja) |
WO (1) | WO2013114980A1 (ja) |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5948260B2 (ja) * | 2013-01-24 | 2016-07-06 | Kyb株式会社 | 流体圧制御装置 |
CN104196803B (zh) * | 2014-09-11 | 2016-04-27 | 中国农业大学 | 一种用于重型拖拉机电液提升器的多功能螺纹插装阀 |
CN104782258A (zh) * | 2015-04-23 | 2015-07-22 | 山东常林道依茨法尔机械有限公司 | 一种小功率轮式拖拉机强压装置 |
JP6603560B2 (ja) * | 2015-12-04 | 2019-11-06 | 川崎重工業株式会社 | 圧力補償ユニット |
US10641388B2 (en) * | 2015-12-07 | 2020-05-05 | Kubota Corporation | Hydraulic system of work machine and work machine |
US10487474B2 (en) | 2017-06-23 | 2019-11-26 | Deere & Company | System and method for hydraulic actuator lock valve |
AU2019231887A1 (en) * | 2018-03-08 | 2020-06-04 | Precision Planting Llc | Fluid control system |
GB2575480A (en) * | 2018-07-11 | 2020-01-15 | Parker Hannifin Emea Sarl | A control valve assembly for a load handling vehicle |
DE102019214228A1 (de) * | 2019-09-18 | 2021-03-18 | Deere & Company | Verfahren zur Erkennung unzulässiger Betriebszustände einer Arbeitshydraulik eines landwirtschaftlichen Traktors |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5330094U (ja) * | 1976-07-28 | 1978-03-15 | ||
JPS6386404U (ja) * | 1986-11-25 | 1988-06-06 | ||
JPS6434879A (en) * | 1987-07-28 | 1989-02-06 | Kawasaki Heavy Ind Ltd | Hydraulic elevator valve gear |
JPH0544702A (ja) * | 1991-08-19 | 1993-02-23 | Nachi Fujikoshi Corp | 昇降シリンダ比例制御回路 |
JPH08182406A (ja) * | 1995-01-09 | 1996-07-16 | Kubota Corp | 作業車の作業装置用操作構造 |
JPH08261206A (ja) | 1996-03-26 | 1996-10-08 | Iseki & Co Ltd | 油圧制御装置 |
JPH09208160A (ja) * | 1996-02-02 | 1997-08-12 | Toyooki Kogyo Co Ltd | エレベータ弁装置 |
JPH10101277A (ja) * | 1996-09-27 | 1998-04-21 | Fujitec Co Ltd | 油圧エレベータ装置 |
Family Cites Families (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2840104A (en) * | 1953-08-03 | 1958-06-24 | Shafer Valve Co | Pressure relief valve |
US3952509A (en) * | 1975-04-10 | 1976-04-27 | Allis-Chalmers Corporation | Hydraulic system combining open center and closed center hydraulic circuits |
JPS62194201U (ja) * | 1986-05-30 | 1987-12-10 | ||
JP2575535B2 (ja) | 1990-04-25 | 1997-01-29 | 三菱電機株式会社 | 周波数変換装置 |
JPH0842512A (ja) * | 1994-08-04 | 1996-02-13 | Showa:Kk | 油圧システムの回路構造 |
US6502393B1 (en) * | 2000-09-08 | 2003-01-07 | Husco International, Inc. | Hydraulic system with cross function regeneration |
JP3651442B2 (ja) | 2001-02-02 | 2005-05-25 | 日本電信電話株式会社 | 血流計及び血流計のセンサ部 |
JP3882756B2 (ja) | 2003-01-30 | 2007-02-21 | 日本電信電話株式会社 | 血流計のセンサ部及び血流計 |
DE10344480B3 (de) * | 2003-09-24 | 2005-06-16 | Sauer-Danfoss Aps | Hydraulische Ventilanordnung |
DE202004014029U1 (de) * | 2004-09-08 | 2006-01-12 | Hawe Hydraulik Gmbh & Co. Kg | Elektrohydraulische Steuervorrichtung |
US7614336B2 (en) * | 2005-09-30 | 2009-11-10 | Caterpillar Inc. | Hydraulic system having augmented pressure compensation |
KR20070090361A (ko) | 2006-03-02 | 2007-09-06 | 가야바코교 가부시기가이샤 | 오퍼레이트 체크 밸브, 유압 구동 유닛 |
DE102007028864A1 (de) * | 2007-03-27 | 2008-10-02 | Robert Bosch Gmbh | Hydraulische Steueranordnung |
US8584453B2 (en) * | 2009-05-01 | 2013-11-19 | Atlas Copco Drilling Solutions, Inc. | Hydrostatic circuit lock valve components, circuits, systems, and method |
JP5330094B2 (ja) | 2009-05-22 | 2013-10-30 | テクノポリマー株式会社 | 多色成形方法及び多色成形品 |
-
2012
- 2012-02-03 JP JP2012021993A patent/JP5860711B2/ja active Active
-
2013
- 2013-01-18 KR KR1020147015986A patent/KR101647571B1/ko active IP Right Grant
- 2013-01-18 CN CN201380004205.0A patent/CN103987970B/zh not_active Expired - Fee Related
- 2013-01-18 WO PCT/JP2013/050981 patent/WO2013114980A1/ja active Application Filing
- 2013-01-18 US US14/370,958 patent/US9683587B2/en not_active Expired - Fee Related
- 2013-01-18 EP EP13743398.3A patent/EP2778435A4/en not_active Withdrawn
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5330094U (ja) * | 1976-07-28 | 1978-03-15 | ||
JPS6386404U (ja) * | 1986-11-25 | 1988-06-06 | ||
JPS6434879A (en) * | 1987-07-28 | 1989-02-06 | Kawasaki Heavy Ind Ltd | Hydraulic elevator valve gear |
JPH0544702A (ja) * | 1991-08-19 | 1993-02-23 | Nachi Fujikoshi Corp | 昇降シリンダ比例制御回路 |
JPH08182406A (ja) * | 1995-01-09 | 1996-07-16 | Kubota Corp | 作業車の作業装置用操作構造 |
JPH09208160A (ja) * | 1996-02-02 | 1997-08-12 | Toyooki Kogyo Co Ltd | エレベータ弁装置 |
JPH08261206A (ja) | 1996-03-26 | 1996-10-08 | Iseki & Co Ltd | 油圧制御装置 |
JPH10101277A (ja) * | 1996-09-27 | 1998-04-21 | Fujitec Co Ltd | 油圧エレベータ装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2778435A4 |
Also Published As
Publication number | Publication date |
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CN103987970B (zh) | 2016-04-13 |
US9683587B2 (en) | 2017-06-20 |
CN103987970A (zh) | 2014-08-13 |
US20150013322A1 (en) | 2015-01-15 |
EP2778435A4 (en) | 2015-08-05 |
EP2778435A1 (en) | 2014-09-17 |
KR20140097351A (ko) | 2014-08-06 |
KR101647571B1 (ko) | 2016-08-10 |
JP2013160289A (ja) | 2013-08-19 |
JP5860711B2 (ja) | 2016-02-16 |
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