WO2023050660A1 - 放油阀、蓄能装置、液压系统和作业机械 - Google Patents

放油阀、蓄能装置、液压系统和作业机械 Download PDF

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Publication number
WO2023050660A1
WO2023050660A1 PCT/CN2022/073532 CN2022073532W WO2023050660A1 WO 2023050660 A1 WO2023050660 A1 WO 2023050660A1 CN 2022073532 W CN2022073532 W CN 2022073532W WO 2023050660 A1 WO2023050660 A1 WO 2023050660A1
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WIPO (PCT)
Prior art keywords
oil
valve
port
working position
valve core
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Application number
PCT/CN2022/073532
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English (en)
French (fr)
Inventor
罗斌
苏广煜
汪锋维
Original Assignee
三一汽车制造有限公司
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Application filed by 三一汽车制造有限公司 filed Critical 三一汽车制造有限公司
Priority to EP22874063.5A priority Critical patent/EP4379220A1/en
Publication of WO2023050660A1 publication Critical patent/WO2023050660A1/zh
Priority to US18/596,311 priority patent/US20240209874A1/en

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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
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • 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
    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F15B1/04—Accumulators
    • 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
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • F15B13/0402—Valve members; Fluid interconnections therefor for linearly sliding valves, e.g. spool 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
    • 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
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/005—Filling or draining of fluid systems
    • 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
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • F15B13/0407—Means for damping the valve member movement
    • 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
    • F15B2201/00—Accumulators
    • F15B2201/40—Constructional details of accumulators not otherwise provided for
    • F15B2201/41—Liquid ports
    • 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
    • F15B2201/00—Accumulators
    • F15B2201/40—Constructional details of accumulators not otherwise provided for
    • F15B2201/41—Liquid ports
    • F15B2201/411—Liquid ports 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
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • 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
    • F15B2211/40515—Flow control characterised by the type of flow control means or valve with variable throttles or orifices
    • 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
    • F15B2211/41—Flow control characterised by the positions of the valve element
    • F15B2211/413—Flow control characterised by the positions of the valve element the positions being continuously variable, e.g. as realised by proportional valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41572—Flow control characterised by the connections of the flow control means in the circuit being connected to a pressure source and an output member
    • 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
    • F15B2211/42—Flow control characterised by the type of actuation
    • F15B2211/428—Flow control characterised by the type of actuation actuated by fluid pressure

Definitions

  • the present application relates to the technical field of hydraulic systems, in particular to an oil discharge valve, an energy storage device, a hydraulic system and an operating machine.
  • accumulators are usually set up to store or recover the hydraulic energy in the hydraulic system and release it when needed, so as to achieve the purpose of energy saving.
  • a group of hydraulic cylinders of the hydraulic system drives the S pipe valve to reciprocate in the hopper, so as to transport the concrete in the hopper through the delivery cylinder to the concrete pumping pipe to realize the delivery of concrete Function.
  • an accumulator is arranged on the oil inlet of the hydraulic cylinder, and hydraulic energy is collected when the accumulator is filled with oil, and hydraulic oil is replenished to the hydraulic cylinder when the accumulator is discharged.
  • the application provides an oil discharge valve, an energy storage device, a hydraulic system and a working machine, which are used to solve the problem in the prior art that the accumulator of the hydraulic system easily causes impact damage to the oil cylinder during the oil discharge process.
  • the present application provides an oil discharge valve, which includes a valve body, a valve core and an elastic element, the valve body is provided with a first oil port and a second oil port, and between the first oil port and the second oil port
  • the spool is provided and communicated with the first oil port and the second oil port, and the spool can move in the valve body so that the spool is in the first working position and the second working position switch between positions;
  • the elastic element is provided between the first end of the spool and the valve body, the first end of the spool communicates with the first oil port, and the first end of the spool communicates with the first oil port.
  • the two ends communicate with the second oil port;
  • valve core When the hydraulic oil in the oil drain valve flows from the first oil port to the second oil port, the valve core can be switched from the second working position to the first oil port under the action of the elastic element a working position;
  • the valve core can compress the elastic element and switch from the first working position to the second working position position; the flow rate of the oil drain valve when the spool works at the second working position is smaller than the flow rate when the spool works at the first working position.
  • the elastic elements when the spool works in the first working position and the second working position, the elastic elements are in a compressed state, and the elastic elements are in the
  • the elastic force of the spool when it works in the first working position is smaller than the elastic force when the spool works in the second working position.
  • the valve body is provided with a limiter, and when the valve core is working at the first working position, the limiter prevents the valve core from moving away from the first working position. The direction of the two working positions moves.
  • an oil discharge valve the valve body is provided with an oil passage, a first back cavity is formed between the first end of the valve core and the valve body, and the elastic element is arranged on the first In a back chamber, the oil passage communicates with the first back chamber and the first oil port to form a first feedback oil passage;
  • the second end of the valve core is provided with a cavity, and the cavity communicates with the second oil port, and the side wall of the cavity is provided with a first oil hole, and the cavity is connected with the first oil port.
  • the oil ports are connected through the first oil hole; the opening of the first oil hole when the spool works at the first working position is larger than that when the spool works at the second working position. The opening of the first oil hole.
  • an oil discharge valve further comprising a damping element, and the damping element is arranged on the first feedback oil circuit.
  • the damping element is any one of a damping hole, a damper and an electronically controlled proportional flow valve.
  • the damper is an adjustable damper.
  • the valve body includes a valve seat and a valve sleeve, the first oil port and the second oil port are both arranged on the valve seat, and the valve seat is provided with a valve core cavity, the valve sleeve is fixed in the valve core cavity, and the valve core is slidably arranged in the valve sleeve; the side wall of the valve sleeve is provided with a second oil hole, and the second oil The hole communicates with the first oil port and the first oil hole.
  • the first back chamber is formed between the first end of the valve core and the first end of the valve sleeve, and the valve sleeve is provided with a damping hole, so The damping hole communicates with the first back cavity and the oil passage.
  • a first annular flow guide groove is provided on the inner surface of the valve core cavity
  • a second annular flow guide groove is provided on the inner surface of the valve sleeve
  • the first oil port , the first annular diversion groove, the second oil hole, the second annular diversion groove and the first oil hole communicate in sequence
  • the first oil hole includes a plurality of first through holes distributed on the side wall of the cavity along the circumferential direction of the valve core
  • the second oil hole includes a plurality of first through holes distributed on the side wall of the cavity along the circumferential direction of the valve sleeve.
  • the first oil hole includes a plurality of first through holes distributed on the side wall of the cavity along the axial direction of the valve core, and is close to the first through hole of the valve core.
  • the diameter of the first through hole at the two ends is smaller than the diameter of the first through hole at the second end away from the valve core.
  • the elastic element is a return spring.
  • the present application also provides an energy storage device, including an accumulator and any of the above-mentioned oil discharge valves, the oil discharge valve is installed on the oil outlet of the accumulator, and the oil outlet of the accumulator is connected to the The second oil ports are connected.
  • the present application also provides a hydraulic system, including an oil pump, an actuator, an accumulator, and any of the above oil discharge valves, the first oil port is connected to the oil outlet of the oil pump and the working oil of the actuator respectively.
  • the second oil port communicates with the oil outlet of the accumulator; or, the hydraulic system includes an oil pump, an actuator and the energy storage device.
  • the present application also provides a work machine, including the above-mentioned hydraulic system.
  • the oil discharge valve, energy storage device, hydraulic system and working machine connect the first oil port and the second oil port on the valve body through the valve core, and connect the first end of the valve core with the first oil port to form a
  • the first feedback oil passage connects the second end of the spool with the second oil port to form the second feedback oil passage, and an elastic element is set between the first end of the spool and the valve body so that when the When the flow direction of hydraulic oil changes, it can realize the automatic switching of the working position of the spool, and change the flow of hydraulic oil flowing through the oil discharge valve through the flow setting of different working positions, so as to realize its automatic control of the output flow.
  • the oil drain flow of the oil drain valve can be reduced by automatically switching the working position when the accumulator is switched from oil charging to oil draining , to prevent damage to the actuator due to rigid impact.
  • Fig. 1 is one of schematic diagrams of the working principle of the oil drain valve provided by the present application.
  • Fig. 2 is the second schematic diagram of the working principle of the oil drain valve provided by the present application.
  • Fig. 3 is the third schematic diagram of the working principle of the oil drain valve provided by the present application.
  • Fig. 4 is one of structural representations of the oil drain valve provided by the present application.
  • Fig. 5 is the second structural diagram of the oil drain valve provided by the present application.
  • Oil drain valve 1. Valve body; 11. The first oil port;
  • Valve seat 16. Valve sleeve; 161. Damping hole;
  • Second feedback oil circuit 6. Damping element; 200. Accumulator.
  • connection should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, Or integrally connected; it can be directly connected, or indirectly connected through an intermediary, and it can be the internal communication of two components.
  • FIG. 1 one of the schematic diagrams of the working principle of the oil discharge valve provided by the present application is shown, and in FIG. 2 , the second schematic diagram of the working principle of the oil discharge valve provided by the present application is shown.
  • FIG. 4 is one of the structural schematic diagrams of the oil discharge valve provided by the present application
  • FIG. 5 is the second structural schematic diagram of the oil discharge valve provided by the present application.
  • the oil drain valve 100 provided in the embodiment of the present application includes a valve body 1 , a valve core 2 and an elastic element 3 .
  • the valve body 1 is provided with a first oil port 11 and a second oil port 12 .
  • a valve core 2 is provided between the first oil port 11 and the second oil port 12 and the valve core 2 communicates with the first oil port 11 and the second oil port 12 .
  • the valve core 2 can move in the valve body 1 so that the valve core 2 can switch between the first working position and the second working position.
  • An elastic element 3 is provided between the first end of the valve core 2 and the valve body 1 .
  • the first end of the valve core 2 communicates with the first oil port 11
  • the second end of the valve core 2 communicates with the second oil port 12 .
  • Figures 1 and 4 show the state of the oil drain valve 100 when the spool 2 is working at the first working position
  • Figures 2 and 5 show the state of the oil draining valve 100 when the spool 2 is working at the second working position status.
  • the valve core 2 can be switched from the second working position to the first working position under the action of the elastic element 3 .
  • the valve core 2 can compress the elastic element 3 and switch from the first working position to the second working position.
  • the flow rate of the oil drain valve 100 when the spool 2 works at the second working position is smaller than the flow rate when the spool 2 works at the first working position.
  • the cavity formed between the first end of the valve core 2 and the valve body 1 communicates with the first oil port 11 to form the first feedback oil passage 4 .
  • the cavity formed between the second end of the valve core 2 and the valve body 1 communicates with the second oil port 12 to form the second feedback oil passage 5 .
  • the elastic element 3 is arranged in the cavity formed between the first end of the valve core 2 and the valve body 1 .
  • the oil discharge valve provided in the embodiment of the present application can be installed on the oil outlet of the accumulator 200 so that the oil outlet of the accumulator 200 is connected to the oil inlet of the actuator through the oil discharge valve 100 .
  • the second oil port 12 is used to connect with the oil outlet of the accumulator 200
  • the first oil port 11 is used to connect with the working oil port of the actuator and the oil outlet of the oil pump.
  • the oil filling and oil discharge of the accumulator 200 both pass through the oil discharge valve 100.
  • the oil pump pumps hydraulic oil to the accumulator 200 for energy storage.
  • the accumulator 200 supplies hydraulic energy to the actuator, and
  • the output hydraulic oil volume of the accumulator 200 is controlled through the oil discharge valve 100 .
  • the valve core 2 works at the first working position.
  • the hydraulic pressure of the hydraulic oil in the first feedback oil passage 4 on the first end of the spool 2 is equal to the hydraulic pressure of the hydraulic oil in the second feedback oil passage 5 on the second end of the spool 2 .
  • the accumulator 200 still has a pressure-holding stage after the oil filling is completed. In the pressure-holding state, the hydraulic pressure on both ends of the valve core 2 is also equal.
  • the elastic element 3 exerts a leftward force on the first end of the valve core 2 to keep it working at the first working position.
  • the hydraulic oil in the first feedback oil circuit 4 acts on the second end of the valve core 2 with a greater force than the second feedback oil circuit.
  • the hydraulic oil in 5 exerts force on the first end of the spool 2, thereby pushing the spool 2 to move to switch to the second working position, so that the output flow of the oil drain valve 100 decreases.
  • the oil drain valve provided by the embodiment of the present application connects the first oil port 11 and the second oil port 12 on the valve body 1 through the valve core 2, and connects the first end of the valve core 2 with the first oil port 11 to form a first
  • the feedback oil passage 4 communicates the second end of the spool 2 with the second oil port 12 to form the second feedback oil passage 5, and an elastic element 3 is provided between the first end of the spool 2 and the valve body 1, so that
  • the flow direction of the hydraulic oil in the oil drain valve 100 changes, the automatic switching of the working position of the spool 2 can be realized, and the flow rate of the hydraulic oil flowing through the oil drain valve 100 can be changed through the flow setting of different working positions to realize its output. Automatic control of flow.
  • the oil drain valve 100 When the second oil port 12 of the oil drain valve 100 is used in communication with the oil outlet of the accumulator 200, when the accumulator 200 is switched from oil charging to oil draining, the oil drain valve can be reduced by automatically switching the working position.
  • the oil discharge flow rate of 100 can prevent the actuator from being damaged due to rigid impact.
  • the elastic element 3 when the valve core 2 is working at the first working position and the second working position, the elastic element 3 is in a compressed state, and the elastic force of the elastic element 3 is smaller than that of the valve when the valve core 2 is working at the first working position.
  • the elastic force of the core 2 when working in the second working position.
  • the elastic restoring force of the elastic element 3 is used to limit the valve core 2 to the first working position.
  • the elastic element 3 is compressed.
  • the elastic element 3 can be a return spring or a return elastic piece, which can act on the valve core 2 through an elastic restoring force to limit it to the first working position.
  • One end of the return spring abuts against the first end of the valve core 2 , and the other end abuts against the valve body 1 .
  • valve body 1 is provided with a limiting member (not shown in the figure), and when the valve core 2 is working at the first working position, the limiting member prevents the valve core 2 from moving away from the second working position.
  • the elastic element 3 pushes the valve core 2 against the limiter, that is, the valve core 2 is limited between the elastic element 3 and the limiter.
  • the valve body 1 is provided with a spool cavity 13, and the limiting member can be a limiting boss or a limiting convex ring protruding from the inner wall of the spool cavity 13; Wall circlips.
  • the valve body 1 of the oil drain valve 100 is provided with an oil passage 14 .
  • a first back cavity is formed between the first end of the valve core 2 and the valve body 1, and the elastic element 3 is disposed in the first back cavity.
  • the oil passage 14 communicates with the first back cavity and the first oil port 11 to form the first feedback oil passage 4 .
  • the second end of the valve core 2 is provided with a cavity 21 , and the cavity 21 communicates with the second oil port 12 .
  • the side wall of the cavity 21 is provided with a first oil hole 211 , and the cavity 21 communicates with the first oil port 11 through the first oil hole 211 .
  • the opening of the first oil hole 211 when the spool 2 works at the first working position is greater than the opening of the first oil hole 211 when the spool 2 works at the second working position.
  • valve body 1 is provided with a valve core cavity 13, and the valve core 2 is slidably installed in the valve core cavity 13 along its axial direction.
  • the first end of the valve body 1 along the sliding direction of the valve core 2 is closed, and the first oil port 11 is opened on one side of the valve body 1 along the sliding direction of the valve core 2 .
  • the cavity formed between the first end of the valve body 1 and the first end of the valve core 2 is the first back cavity, and the first back cavity communicates with the first oil port 11 through the oil passage 14 to form the first feedback oil Road 4.
  • the second oil port 12 is opened at the second end of the valve body 1 along the sliding direction of the valve core 2 , and an axially open cavity is formed between the valve body 1 and the valve core 2 .
  • the cavity communicates with the second oil port 12 and the cavity 21 to form an oil passage along the axial direction of the valve core 2 , and the oil passage is the second feedback oil passage 5 .
  • the cavity 21 is always in communication with the first oil port 11 and the second oil port 12.
  • the oil drain valve 100 is installed on the oil outlet of the accumulator 200 , and the second oil port 12 is connected with the oil outlet of the accumulator 200 .
  • the hydraulic oil in the accumulator 200 enters the oil drain valve 100 along the axial direction of the spool 2 , and then is discharged from the first oil port 11 through the cavity 21 along the radial direction of the spool 2 .
  • the accumulator 200 is filled with oil, external hydraulic oil enters the cavity 21 from the first oil port 11 along the radial direction of the valve core 2 , and then fills into the accumulator 200 from the second oil port 12 along the axial direction of the valve core 2 .
  • the second oil port 12 can also be opened on one side of the valve body 1 along the sliding direction of the valve core 2, and the second end of the valve body 1 along the sliding direction of the valve core 2 is closed, so that the second end of the valve body 1
  • the cavity formed between the two ends and the second end of the valve core 2 is a second back cavity, and the second back cavity communicates with the second oil port 12 to form the second feedback oil passage 5 .
  • the oil discharge valve provided by the embodiment of the present application further includes a damping element 6 , and the damping element 6 is arranged on the first feedback oil passage 4 .
  • the damping element 6 may be a damping hole or a damper or a proportional flow valve arranged on the first feedback oil passage 4 .
  • the hydraulic pressure acting on the first end of the spool 2 decreases.
  • the hydraulic pressure acting on the second end of the spool 2 is greater than the hydraulic pressure acting on the first end of the spool 2, the spool 2 switches to the second working position to realize oil discharge with a small flow rate, so as to avoid the actuator at the end of the stroke. Produce a large rigid impact.
  • Fig. 3 is the third schematic diagram of the working principle of the oil drain valve provided by the present application.
  • the damping element 6 is an electronically controlled proportional flow valve, which can also adjust the delay time when the oil discharge valve 100 is switched from the first working position to the second working position.
  • the valve body 1 includes a valve seat 15 and a valve sleeve 16 .
  • the first oil port 11 , the second oil port 12 and the valve core cavity 13 are all arranged on the valve seat 15 , and the valve sleeve 16 is fixed in the valve core cavity 13 .
  • the valve core 2 is slidably disposed in the valve sleeve 16 .
  • a second oil hole 162 is provided on the side wall of the valve sleeve 16 , and the second oil hole 162 communicates with the first oil port 11 and the first oil hole 211 .
  • first end of the valve sleeve 16 corresponds to the first end of the valve core 2 and both communicate with the first oil port 11
  • second end of the valve sleeve 16 corresponds to the second end of the valve core 2 and both communicate with the second oil port.
  • Port 12 is connected.
  • the first back cavity is formed between the first end of the valve core 2 and the first end of the valve sleeve 16 .
  • the valve sleeve 16 is provided with a damping hole 161 , and the damping hole 161 communicates with the first back chamber and the oil passage 14 .
  • the damping hole 161 is used as the damping element 6 on the first feedback oil circuit 4 shown in Fig. 1-Fig. Switch from the first working position to the second working position under the action.
  • a buffer chamber 17 is formed between the first end of the valve sleeve 16 and the valve seat 15 , and the buffer chamber 17 communicates with the damping hole 161 and the oil passage 14 .
  • the damping hole 161 is disposed at the first end of the valve sleeve 16 .
  • the central axis of the damping hole 161 coincides with the central axis of the valve core 2 .
  • the first oil port 11, the oil passage 14, the buffer chamber 17, the damping hole 161 and the first back chamber are connected in sequence to form the first feedback oil passage 4.
  • the inner surface of the valve core cavity 13 is provided with a first annular guide groove 18
  • the inner surface of the valve sleeve 16 is provided with a second annular guide groove 163
  • the first oil port 11 , the first annular guide groove 18 , the second oil hole 162 , the second annular guide groove 163 and the first oil hole 211 are connected in sequence.
  • the first oil hole 211 includes a plurality of first through holes distributed on the side wall of the cavity 21 along the circumferential direction of the valve core 2
  • the second oil hole 162 includes a plurality of first through holes distributed on the side wall of the valve sleeve 16 along the circumferential direction of the valve sleeve 16 . multiple second vias.
  • the hydraulic oil that enters the cavity 21 from the second oil port 12 can enter the first annular guide groove 18 from a plurality of first through holes arranged circumferentially on the valve core 2 , and then flow from the circumferentially arranged holes of the valve sleeve 16 A plurality of second through holes enter the second annular guide groove 163 and finally flow out from the first oil port 11 .
  • the first oil hole 211 includes a plurality of first through holes distributed on the side wall of the cavity 21 along the axial direction of the valve core 2, and the diameter of the first through holes near the second end of the valve core 2 is smaller than The diameter of the first through hole at the second end away from the spool 2 .
  • the second oil hole 162 includes a plurality of second through holes distributed on the side wall of the valve sleeve 16 along the axial direction of the valve sleeve 16 .
  • a plurality of first through holes distributed on the side wall of the cavity 21 along the circumferential direction of the valve core 2 form a first oil hole group
  • the first oil holes 211 include A plurality of first oil hole groups in the wall. That is, a plurality of first through holes are arranged in a matrix on the side wall of the cavity 21 .
  • a plurality of second through holes distributed on the side wall of the valve sleeve 16 along the circumferential direction of the valve sleeve 16 form a second oil hole group
  • the second oil holes 162 include the axial distribution along the valve sleeve 16 and the A plurality of second oil hole groups in the wall. That is, a plurality of second oil holes are arranged in a matrix on the side wall of the valve sleeve 16 .
  • the present application also provides an energy storage device, which includes an accumulator 200 and any of the above oil discharge valves 100, the oil discharge valve 100 is installed on the oil outlet of the accumulator 200, and the accumulator 200 The oil outlet communicates with the second oil port 12 .
  • the second oil port 12 of the oil drain valve 100 and the oil outlet port of the accumulator 200 can be fixedly connected so that the oil drain valve 100 and the accumulator 200 are integrated as a whole, which facilitates the installation of the energy storage device.
  • the second oil port 12 of the oil drain valve 100 is detachably connected to the oil outlet of the accumulator 200 through threads or flanges, so as to facilitate installation, disassembly and replacement of the oil drain valve 100 and the accumulator 200 .
  • the present application also provides a hydraulic system.
  • the hydraulic system includes an oil pump, an actuator, an accumulator 200 and the oil discharge valve 100 described in any of the above-mentioned embodiments.
  • the first oil port 11 communicates with the oil outlet of the oil pump and the working oil port of the actuator respectively, and the second oil port 12 communicates with the oil outlet of the accumulator 200.
  • the hydraulic system includes an oil pump, an actuator and the energy storage device described in the above embodiments, the oil outlet of the oil pump communicates with the first oil port 11, and the first oil port 11 communicates with the working oil port of the actuator.
  • the oil pump can be used as a power source of the actuator, that is, the accumulator and the actuator share a power source.
  • the hydraulic system also includes a reversing valve, and the oil pump is connected with the actuator through the reversing valve.
  • the reversing valve includes a first reversing port, a second reversing port, an oil inlet and an oil return port.
  • the oil outlet of the oil pump communicates with the oil inlet port of the reversing valve and the first oil port 11 of the oil discharge valve 100 respectively, and the first reversing port and the second reversing port are connected with the first control oil port and the second reversing port of the actuator respectively.
  • the second control oil port is connected, and the oil return port of the reversing valve is connected with the oil tank.
  • the reversing valve is provided with a first working position and a second working position.
  • the oil inlet port of the reversing valve communicates with the first reversing port
  • the oil return port of the reversing valve communicates with the second reversing port.
  • the oil inlet port of the reversing valve communicates with the second reversing port
  • the oil return port of the reversing valve communicates with the first reversing port.
  • the first control oil port communicates with the rodless chamber of the hydraulic cylinder
  • the second control oil port communicates with the rod chamber of the hydraulic cylinder.
  • the hydraulic oil pumped by the oil pump enters the rod chamber of the working cylinder through the oil inlet of the reversing valve and the second reversing port in order to drive the piston of the working cylinder retract.
  • the accumulator 200 enters the oil discharge state, and also delivers hydraulic oil to the rod cavity of the working oil cylinder to drive the piston of the working oil cylinder to shrink rapidly.
  • the first feedback oil passage 4 of the oil discharge valve 100 When the first feedback oil passage 4 of the oil discharge valve 100 is provided with a damping element 6, it can be a period of time before the spool of the reversing valve is switched from the first working position to the second working position, that is, the oil discharging valve 100 For a period of time after the spool switches from the oil-filled state to the oil-drained state, the piston of the working cylinder can shrink at a faster speed. After a period of time, the spool of the oil drain valve 100 is switched to the second working position, so that the output flow of the accumulator 200 is reduced, so as to reduce the oil supply to the rod chamber of the working cylinder, thereby preventing the piston from colliding with the cylinder at the end of the stroke. body in a rigid collision.
  • the present application also provides an operating machine, which may be a pump truck, a vehicle-mounted pump, a tow pump, a jack, and a fire engine.
  • the work machine includes the hydraulic system described in the above embodiments.
  • the actuator includes a first swing cylinder and a second swing cylinder.
  • the rodless cavity of the first swing cylinder communicates with the first reversing port of the reversing valve
  • the rod cavity of the first swing cylinder communicates with the rod cavity of the second swing cylinder
  • the rodless cavity of the second swing cylinder communicates with the reversing valve.
  • the second reversing port of the valve is connected.

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Abstract

一种放油阀（100）及包括其的蓄能装置（200）、液压系统和作业机械，该放油阀包括阀体（1）、阀芯（2）和弹性元件（3），阀体设有第一油口（11）和第二油口（12），阀芯连通第一油口和第二油口，阀芯可在阀体中移动以使阀芯在第一工作位和第二工作位之间切换；阀芯的第一端和阀体之间设有弹性元件，阀芯的第一端与第一油口连通，阀芯的第二端与第二油口连通；当放油阀内的液压油流向从第一油口到第二油口时，阀芯能够在弹性元件的作用下从第二工作位切换到第一工作位；当放油阀内的液压油流向从第二油口到第一油口时，阀芯能够压缩弹性元件并从第一工作位切换到第二工作位；放油阀在阀芯工作于第二工作位时的流量小于阀芯工作于第一工作位时的流量。

Description

放油阀、蓄能装置、液压系统和作业机械
相关申请的交叉引用
本申请要求于2021年09月29日提交的申请号为202111154736.0，名称为“放油阀、蓄能装置、液压系统和作业机械”的中国专利申请的优先权，其通过引用方式全部并入本文。
技术领域
本申请涉及液压系统技术领域，尤其涉及一种放油阀、蓄能装置、液压系统和作业机械。
背景技术
目前在一些液压系统中，通常会设置蓄能器，用于储存或回收液压系统中的液压能，在需要时释放出来，以达到节能的目的。
例如，在混凝土泵送设备作业过程中，通过液压系统的一组液压缸驱动S管阀在料斗中往复运动，以将料斗中的混凝土通过输送缸输送经混凝土泵送管中，实现混凝土的输送功能。其中，液压缸的进油油路上设置有蓄能器，在蓄能器充油时收集液压能，在蓄能器放油时向液压缸补充液压油。
然而，相关现有技术中，液压系统中的蓄能器在放油过程中，其输出的液压油流量不受控制，在油缸行程的末端，活塞通常在刚性冲击力的作用下停止，容易对油缸造成损坏。
发明内容
本申请提供一种放油阀、蓄能装置、液压系统和作业机械，用以解决现有技术中的液压系统的蓄能器在放油过程中容易对油缸造成冲击损坏的问题。
本申请提供一种放油阀，包括阀体、阀芯和弹性元件，所述阀体设有第一油口和第二油口，所述第一油口和所述第二油口之间设有所述阀芯且所述阀芯连通所述第一油口和第二油口，所述阀芯可在所述阀体中移动以使所述阀芯在第一工作位和第二工作位之间切换；所述阀芯的第一端和所述阀体之间设有所述弹性元件，所述阀芯的第一端与所述第一油口连通，所述阀芯的 第二端与所述第二油口连通；
当所述放油阀内的液压油流向从所述第一油口到所述第二油口时，所述阀芯能够在弹性元件的作用下从所述第二工作位切换到所述第一工作位；
当所述放油阀内的液压油流向从所述第二油口到所述第一油口时，所述阀芯能够压缩弹性元件并从所述第一工作位切换到所述第二工作位；所述放油阀在所述阀芯工作于所述第二工作位时的流量小于所述阀芯工作于所述第一工作位时的流量。
根据本申请提供一种的放油阀，在所述阀芯工作于所述第一工作位和所述第二工作位时，所述弹性元件均处于压缩状态，且所述弹性元件在所述阀芯工作于所述第一工作位时的弹力小于所述阀芯工作于所述第二工作位时的弹力。
根据本申请提供一种的放油阀，所述阀体上设有限位件，当所述阀芯工作于所述第一工作位时所述限位件阻止所述阀芯向远离所述第二工作位的方向移动。
根据本申请提供一种的放油阀，所述阀体内设有油路，所述阀芯的第一端与所述阀体之间形成第一背腔，所述弹性元件设置于所述第一背腔内，所述油路连通所述第一背腔和所述第一油口形成第一反馈油路；
所述阀芯的第二端设有腔体，所述腔体与所述第二油口相连通，所述腔体的侧壁设有第一油孔，所述腔体与所述第一油口通过所述第一油孔相连通；所述阀芯工作于所述第一工作位时所述第一油孔的开度大于所述阀芯工作于所述第二工作位时所述第一油孔的开度。
根据本申请提供一种的放油阀，还包括阻尼元件，所述阻尼元件设置于所述第一反馈油路上。
根据本申请提供一种的放油阀，所述阻尼元件为阻尼孔、阻尼器和电控比例流量阀中的任一种。
根据本申请提供一种的放油阀，所述阻尼器为可调式阻尼器。
根据本申请提供一种的放油阀，所述阀体包括阀座和阀套，所述第一油口和所述第二油口均设置于所述阀座，所述阀座设有阀芯腔，所述阀套固定于所述阀芯腔内，所述阀芯可滑动设置于所述阀套内；所述阀套的侧壁上设有第二油孔，所述第二油孔连通所述第一油口和所述第一油孔。
根据本申请提供一种的放油阀，所述第一背腔形成于所述阀芯的第一端和所述阀套的第一端之间，所述阀套上设有阻尼孔，所述阻尼孔连通所述第一背腔和所述油路。
根据本申请提供一种的放油阀，所述阀芯腔的内侧面设有第一环形导流槽，所述阀套的内侧面设有第二环形导流槽，所述第一油口、所述第一环形导流槽、所述第二油孔、所述第二环形导流槽和所述第一油孔依次连通；
所述第一油孔包括沿所述阀芯的周向分布于所述腔体侧壁的多个第一通孔，所述第二油孔包括沿所述阀套的周向分布于所述阀套侧壁的多个第二通孔。
根据本申请提供一种的放油阀，所述第一油孔包括沿所述阀芯的轴向分布于所述腔体侧壁有多个第一通孔，且靠近所述阀芯的第二端的所述第一通孔的孔径小于远离所述阀芯的第二端的所述第一通孔的孔径。
根据本申请提供一种的放油阀，所述弹性元件为复位弹簧。
本申请还提供一种蓄能装置，包括蓄能器和上述任一种放油阀，所述放油阀安装于所述蓄能器的出油口，所述蓄能器的出油口与所述第二油口相连通。
本申请还提供一种液压系统，包括油泵、执行元件、蓄能器和上述任一种放油阀，所述第一油口分别与所述油泵的出油口和所述执行元件的工作油口相连通，所述第二油口与所述蓄能器的出油口相连通；或者，所述液压系统包括油泵、执行元件和上述蓄能装置。
本申请还提供一种作业机械，包括上述液压系统。
本申请提供的放油阀、蓄能装置、液压系统和作业机械，通过阀芯连通阀体上的第一油口和第二油口，将阀芯的第一端与第一油口连通形成第一反馈油路，将阀芯的第二端与第二油口连通形成第二反馈油路，并在阀芯的第一端和阀体之间设置弹性元件，使得当放油阀内的液压油的流向发生变化时，能够实现阀芯工作位的自动切换，并通过不同工作位的流量设置改变流经放油阀的液压油流量，实现其对输出流量的自动控制。当该放油阀的第二油口与蓄能器的出油口连通使用时，可在蓄能器从充油切换到放油时，通过自动切换工作位减小放油阀的放油流量，防止执行元件发生刚性冲击而造成损坏。
附图说明
为了更清楚地说明本申请或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1是本申请提供的放油阀工作原理示意图之一；
图2是本申请提供的放油阀工作原理示意图之二；
图3是本申请提供的放油阀工作原理示意图之三；
图4是本申请提供的放油阀的结构示意图之一；
图5是本申请提供的放油阀的结构示意图之二；
附图标记：
100、放油阀；        1、阀体；             11、第一油口；
12、第二油口；       13、阀芯腔；          14、油路；
15、阀座；           16、阀套；            161、阻尼孔；
162、第二油孔；      163、第二环形导流槽； 17、缓冲腔；
18、第一环形导流槽； 2、阀芯；             21、腔体；
211、第一油孔；      3、弹性元件；         4、第一反馈油路；
5、第二反馈油路；    6、阻尼元件；         200、蓄能器。
具体实施方式
为使本申请的目的、技术方案和优点更加清楚，下面将结合本申请中的附图，对本申请中的技术方案进行清楚、完整地描述，显然，所描述的实施例是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
在本申请实施例的描述中，需要说明的是，除非另有明确的规定和限定，术语“第一”“第二”是为了清楚说明产品部件进行的编号，不代表任何实质性区别。“左”“右”的方向均以附图所示方向为准。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请实施例中的具体含义。
在本申请的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”“相连”“连接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是直接相连，也可以通过中间媒介间接相 连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以具体情况理解上述术语在本申请中的具体含义。
下面结合图1至图5描述本申请的放油阀和蓄能装置。
如图1所示为本申请提供的放油阀工作原理示意图之一，如图2所示为本申请提供的放油阀工作原理示意图之二。如图4所示为本申请提供的放油阀的结构示意图之一，如图5所示为本申请提供的放油阀的结构示意图之二。
本申请实施例提供的放油阀100包括阀体1、阀芯2和弹性元件3。阀体1设有第一油口11和第二油口12。第一油口11和第二油口12之间设有阀芯2且阀芯2连通第一油口11和第二油口12。阀芯2可在阀体1中移动以使阀芯2在第一工作位和第二工作位之间切换。阀芯2的第一端和阀体1之间设有弹性元件3。阀芯2的第一端与第一油口11连通，阀芯2的第二端与第二油口12连通。
图1和图4示出的放油阀100在阀芯2工作于第一工作位时的状态，图2和图5示出的是放油阀100在阀芯2工作于第二工作位时的状态。当放油阀100内的液压油流向从第一油口11到第二油口12时，阀芯2能够在弹性元件3的作用下从第二工作位切换到第一工作位。当放油阀100内的液压油流向从第二油口12到第一油口11时，阀芯2能够压缩弹性元件3并从第一工作位切换到第二工作位。放油阀100在阀芯2工作于第二工作位时的流量小于阀芯2工作于第一工作位时的流量。
其中，阀芯2的第一端与阀体1之间形成的腔体与第一油口11相连通形成第一反馈油路4。阀芯2的第二端与阀体1之间形成的腔体与第二油口12相连通形成第二反馈油路5。弹性元件3设置于阀芯2的第一端与阀体1之间形成的腔体内。
本申请实施例提供的放油阀可安装于蓄能器200的出油口，使蓄能器200的出油口通过该放油阀100与执行元件的进油口连接。在使用时，第二油口12用于与蓄能器200的出油口连接，第一油口11用于与执行元件的工作油口以及油泵的出油口连接。蓄能器200的充油和放油均经过该放油阀100，充油时油泵向蓄能器200泵送液压油进行蓄能，放油时蓄能器200向执行元件补充液压能，并通过该放油阀100对蓄能器200输出液压油量进行控制。
如图1和图4所示，当放油阀100内的液压油流向为从第一油口11流向 第二油口12，即第一油口11作为进油口，第二油口12作为出油口时，阀芯2工作于第一工作位，放油阀100处于充油状态，对蓄能器200进行充油。
如图2和图5所示，当放油阀100内的液压油流向从第一油口11到第二油口12切换到第二油口12到第一油口11，即切换成第二油口12作为进油口，第一油口11作为出油口时，放油阀100从充油状态切换为放油状态，阀芯2能够从第一工作位切换到第二工作位，使液压油的流量减小。
具体地，当放油阀100处于稳定充油状态时，阀芯2工作于第一工作位。此时，第一反馈油路4内的液压油对阀芯2的第一端的液压力与第二反馈油路5内的液压油对阀芯2的第二端的液压力相等。通常蓄能器200在充油完成之后还会存在保压阶段。在保压状态下，阀芯2两端受到的液压力也相等。当放油阀100处于充油状态和保压状态时，弹性元件3对阀芯2的第一端施加向左的力，以保持其工作于第一工作位。
当放油阀100从充油状态切换到放油状态时，由于液油的流动方向改变，第一反馈油路4内的液压油对阀芯2的第二端的作用力大于第二反馈油路5内的液压油对阀芯2的第一端的作用力，从而推动阀芯2移动以向第二工作位切换，使放油阀100的输出流量减小。
在阀芯2工作于第二工作位的情况下，当放油阀100内的液压油流向从第二油口12到第一油口11切换到第一油口11到第二油口12时，放油阀100从放油状态切换到充油状态。此时由于液油的流动方向改变，第一反馈油路4内的液压油对阀芯2的第一端的作用力大于第二反馈油路5内的液压油对阀芯2的第二端的作用力，从而推动阀芯2移动同时压缩弹性元件3，使阀芯2以从第二工作位切换到第一工作位，以恢复大流量向蓄能器200充油。
本申请实施例提供的放油阀，通过阀芯2连通阀体1上的第一油口11和第二油口12，将阀芯2的第一端与第一油口11连通形成第一反馈油路4，将阀芯2的第二端与第二油口12连通形成第二反馈油路5，并在阀芯2的第一端和阀体1之间设有弹性元件3，使得当放油阀100内的液压油的流向发生变化时，能够实现阀芯2工作位的自动切换，并通过不同工作位的流量设置改变流经放油阀100的液压油流量，实现其对输出流量的自动控制。当该放油阀100的第二油口12与蓄能器200的出油口连通使用时，可在蓄能器200从充油切换到放油时，通过自动切换工作位减小放油阀100的放油流量，防 止执行元件发生刚性冲击而造成损坏。
本申请实施例中，在阀芯2工作于第一工作位和第二工作位时，弹性元件3均处于压缩状态，且弹性元件3在阀芯2工作于第一工作位时的弹力小于阀芯2工作于第二工作位时的弹力。阀芯2工作于第一工作位时，利用弹性元件3的弹性回复力将阀芯2限制于第一工作位。在阀芯2从第一工作位向第二工作位切换时，压缩弹性元件3。
其中，弹性元件3可以为复位弹簧或复位弹片等可以通过弹性回复力作用于阀芯2以将其限位于第一工作位的元件。复位弹簧的一端与阀芯2的第一端抵接，另一端与阀体1抵接。
进一步地，阀体1上设有限位件(图中未示出)，当阀芯2工作于第一工作位时限位件阻止阀芯2向远离第二工作位的方向移动。阀芯2工作于第一工作位时，弹性元件3将阀芯2推至与限位件相抵，即阀芯2被限位于弹性元件3和限位件之间。其中，阀体1设有阀芯腔13，限位件可以为凸设于阀芯腔13的内侧壁的限位凸台或限位凸环；或者限位件为设置于阀芯腔13内侧壁的卡簧。
如图4和图5所示，本申请实施例中，放油阀100的阀体1设有油路14。阀芯2的第一端与阀体1之间形成第一背腔，弹性元件3设置于第一背腔内。油路14连通第一背腔和第一油口11形成第一反馈油路4。阀芯2的第二端设有腔体21，腔体21与第二油口12相连通。腔体21的侧壁设有第一油孔211，腔体21与第一油口11通过第一油孔211相连通。阀芯2工作于第一工作位时第一油孔211的开度大于阀芯2工作于第二工作位时第一油孔211的开度。
具体地，阀体1设有阀芯腔13，阀芯2沿其轴向可滑动安装于阀芯腔13内。阀体1沿阀芯2滑动方向上的第一端封闭，第一油口11开设于阀体1沿阀芯2滑动方向上的一侧。阀体1的第一端与阀芯2的第一端之间形成的腔体为所述第一背腔，第一背腔与第一油口11通过油路14连通以形成第一反馈油路4。
第二油口12开设于阀体1沿阀芯2滑动方向上的第二端，阀体1与阀芯2之间形成轴向开口的腔体。该腔体连通第二油口12和腔体21形成沿阀芯2轴向的油道，该油道即为第二反馈油路5。在阀芯2滑动过程中，腔体21始 终与第一油口11和第二油口12相连通。
将该放油阀100安装于蓄能器200的出油口，第二油口12与蓄能器200的出油口相连。蓄能器200放油时，蓄能器200内的液压油沿阀芯2的轴向进入放油阀100，然后经腔体21沿阀芯2的径向从第一油口11排出。蓄能器200充油时，外部液压油沿阀芯2的径向从第一油口11进入腔体21，然后沿阀芯2的轴向从第二油口12充入蓄能器200。
需要说明的是，第二油口12也可开设于阀体1沿阀芯2滑动方向上的一侧，阀体1沿阀芯2滑动方向上的第二端封闭，使阀体1的第二端与阀芯2的第二端之间形成的腔体为第二背腔，第二背腔与第二油口12连通以形成所述第二反馈油路5。
如图4所示，当放油阀100处于稳定充油状态时，液压油从第一油口11进入放油阀100。一部分液压油从第一油口11流入到腔体21，另一部液压油经油路14流入第一背腔。此时阀芯2的第一端和第二端受到同等大小的液压力。此时阀芯2在弹性元件的作用下保持工作在第一工作位，以保证阀芯2上的第一油孔211的开度为最大，实现大流量充油。
如图5所示，当放油阀100从上述充油状态切换到放油状态时，由于液油的流动方向改变，进入第二反馈油路5的液压油产生稳态液动力，并且稳态液动力逐渐增大。当作用于阀芯2第二端的稳态液动力与液压力的合力大于作用于阀芯2第一端的液压力和弹性力的合力时，推动阀芯2右移，将阀芯2切换到第二工作位。此时阀芯2上的第一油孔211的开度得以减小，使第一油口11以小油量输出液压油。
当放油阀100从上述放油状态切换到充油状态时，由于液压油流动方向改变，以及第一油孔211的节流作用，液压油对阀芯2第一端的作用力大于液压油对阀芯2的第二端的作用力，从而推动阀芯2左移，将阀芯2切换到第一工作位。此时阀芯2上的第一油孔211的开度回复到最大开度，使第二油口12以大流量输出液压油。
如图1和图2所示，本申请实施例提供的放油阀还包括阻尼元件6，阻尼元件6设置于所述第一反馈油路4上。其中，阻尼元件6可以为设置于第一反馈油路4上的阻尼孔或阻尼器或比例流量阀。
当放油阀100的阀芯2工作于第一工作位时，将液压油流向从第一油口 11到第二油口12切换为从第二油口12到第一油口11。此时，由于阻尼元件6的存在，作用于阀芯2第一端的液压力不能立即卸载，使得阀芯2在一定时间段内保持工作于第一工作位，使蓄能器200具有较高的出口流量，以满足工作元件在前期的大流量需求。
一定时间段后，随着液压油由第一反馈油路4排出到第一油口11，作用于阀芯2第一端的液压力减小。当作用于阀芯2的第二端的液压力大于作用于阀芯2的第一端的液压力时，阀芯2切换到第二工作位，实现小流量放油，以避免执行元件在行程末端产生较大的刚性冲击。
其中，可通过更换不同规格的阻尼元件6实现对不同型号执行元件液压系统的匹配调节。进一步地，如图3所示为本申请提供的放油阀工作原理示意图之三。
本申请一实施例中，阻尼元件6选用可调式阻尼器。以便于通过调节阻尼器来调节放油阀100从第一工作位切换到第二工作位的延迟时间。以匹配不同型号执行元件的液压系统。
本申请另一实施例中，阻尼元件6选用电控比例流量阀，同样可实现对放油阀100从第一工作位切换到第二工作位时的延迟时间的调节。
本申请实施例中，阀体1包括阀座15和阀套16。第一油口11、第二油口12和阀芯腔13均设置于阀座15，阀套16固定于阀芯腔13内。阀芯2可滑动设置于阀套16内。阀套16的侧壁上设有第二油孔162，第二油孔162连通第一油口11和第一油孔211。
其中，阀套16的第一端和阀芯2的第一端对应并均与第一油口11连通，阀套16的第二端和阀芯2的第二端对应并均与第二油口12连通。
本申请实施例中，第一背腔形成于阀芯2的第一端和阀套16的第一端之间。阀套16上设有阻尼孔161，阻尼孔161连通第一背腔和油路14。阻尼孔161即作为图1-图3所示的第一反馈油路4上的阻尼元件6，或者在该阻尼孔161处安装阻尼元件6，实现在阀芯2在一定时间段之后在液压力作用下从第一工作位切换到第二工作位。
可选地，阀套16的第一端与阀座15之间形成有缓冲腔17，缓冲腔17连通阻尼孔161和油路14。阻尼孔161设置于阀套16的第一端。可选地，阻尼孔161的中心轴线与阀芯2的中心轴线重合。第一油口11、油路14、缓 冲腔17、阻尼孔161以及第一背腔依次连通形成所述第一反馈油路4。
本申请实施例中，阀芯腔13的内侧面设有第一环形导流槽18，阀套16的内侧面设有第二环形导流槽163。第一油口11、第一环形导流槽18、第二油孔162、第二环形导流槽163和第一油孔211依次连通。其中，第一油孔211包括沿阀芯2的周向分布于腔体21侧壁的多个第一通孔，第二油孔162包括沿阀套16的周向分布于阀套16侧壁的多个第二通孔。
从第二油口12进入腔体21内的液压油能够从阀芯2上周向布置的多个第一通孔进入到第一环形导流槽18，然后从阀套16上周向布置的多个第二通孔进入到第二环形导流槽163，最后从第一油口11流出。
本申请实施例中，第一油孔211包括沿阀芯2的轴向分布于腔体21侧壁有多个第一通孔，且靠近阀芯2的第二端的第一通孔的孔径小于远离阀芯2的第二端的第一通孔的孔径。如此，在阀芯2从第一工作位切换到第二工作位时，可通过移动较小的行程完成对放油流量的控制，有利于减小放油阀100的体积。相应的，第二油孔162包括沿阀套16的轴向分布于阀套16侧壁的多个第二通孔。
进一步地，沿阀芯2的周向分布于腔体21侧壁的多个第一通孔形成第一油孔组，第一油孔211包括沿阀芯2的轴向分布于腔体21侧壁的多个第一油孔组。即多个第一通孔在腔体21的侧壁上呈矩阵式排布。相应的，沿阀套16的周向分布于阀套16侧壁的多个第二通孔形成第二油孔组，第二油孔162包括沿阀套16的轴向分布与阀套16侧壁的多个第二油孔组。即多个第二油孔在阀套16的侧壁上呈矩阵式排布。
本申请还提供一种蓄能装置，该蓄能装置包括蓄能器200和上述任一种放油阀100，放油阀100安装于蓄能器200的出油口，且蓄能器200的出油口与第二油口12相连通。
其中，放油阀100的第二油口12与蓄能器200的出油口可固定连接以使放油阀100和蓄能器200集成为一个整体，方便蓄能装置的安装。或者，放油阀100的第二油口12与蓄能器200的出油口通过螺纹或法兰可拆卸连接，以便于放油阀100与蓄能器200的安装、拆卸和更换。
本申请还提供一种液压系统。该液压系统包括油泵、执行元件、蓄能器200和上述任一实施例所述的放油阀100。所述第一油口11分别与油泵的出 油口和执行元件的工作油口相连通，第二油口12与蓄能器200的出油口相连通。
或者，该液压系统包括油泵、执行元件和上述实施例所述的蓄能装置，油泵的出油口与第一油口11连通，第一油口11与执行元件的工作油口连通。
其中，油泵用于向蓄能器200或蓄能装置内充液压油。当执行元件卸载时，蓄能器200用于向执行元件输送液压油。通过设置本申请提供的放油阀100，可对蓄能器200向执行元件输送的液压油量进行控制，防止蓄能器200放油过程中对执行元件造成较大冲击，以保护执行元件。
进一步地，所述油泵可作为执行元件的动力源，即蓄能器和执行元件共用动力源。其中，该液压系统还包括换向阀，油泵通过换向阀与执行元件相连。换向阀包括第一换向口、第二换向口、进油口和回油口。油泵的出油口分别与换向阀的进油口和放油阀100的第一油口11连通，第一换向口和第二换向口分别与执行元件的第一控制油口和第二控制油口连通，换向阀的回油口与油箱相连。
换向阀设有第一工作位和第二工作位。在换向阀的阀芯工作于第一工作位时，换向阀的进油口与第一换向口连通，换向阀的回油口与第二换向口连通。在换向阀的阀芯工作于第二工作位时，换向阀的进油口与第二换向口连通，换向阀的回油口与第一换向口连通。
当执行元件为液压缸时，第一控制油口连通液压缸的无杆腔，第二控制油口连通液压缸的有杆腔。在该液压系统的工作过程中，当换向阀的阀芯工作于第一工作位时，油泵泵出的液压油一部分依次经过换向阀的进油口和第一换向口进入工作油缸的无杆腔，以驱动工作油缸的活塞伸出进行做功；另一部分经过第一油口11进入蓄能器200，以给蓄能器200充油。
当换向阀的阀芯工作于第二工作位时，油泵泵出的液压油依次经过换向阀的进油口和第二换向口进入工作油缸的有杆腔，以驱动工作油缸的活塞缩回。与此同时，蓄能器200进入放油状态，也向工作油缸的有杆腔输送液压油，以驱动工作油缸的活塞加速收缩。
当放油阀100的第一反馈油路4上设置有阻尼元件6时，可以在换向阀的阀芯从第一工作位切换到第二工作位的开始一段时间，也就是放油阀100的阀芯从充油状态切换到放油状态后的开始一段时间内，工作油缸的活塞能 够以较快的速度收缩。持续一段时间后，放油阀100的阀芯切换到第二工作位，使蓄能器200的输出流量减小，以减少对工作油缸有杆腔的供油，从而避免活塞在行程末端与缸体发生刚性碰撞。
本申请还提供一种作业机械，所述作业机械可以为泵车、车载泵、拖泵、起重器和消防车等作业机械。该作业机械包括上述实施例所述的液压系统。当该作业机械为混凝土泵车时，所述执行元件包括第一摆缸和第二摆缸。第一摆缸的无杆腔与换向阀的第一换向口连通，第一摆缸的有杆腔与第二摆缸的有杆腔连通，第二摆缸的无杆腔与换向阀的第二换向口连通。
最后应说明的是：以上实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的精神和范围。

Claims (15)

  1. 一种放油阀，其特征在于，包括阀体、阀芯和弹性元件，所述阀体设有第一油口和第二油口，所述第一油口和所述第二油口之间设有所述阀芯且所述阀芯连通所述第一油口和第二油口，所述阀芯可在所述阀体中移动以使所述阀芯在第一工作位和第二工作位之间切换；所述阀芯的第一端和所述阀体之间设有所述弹性元件，所述阀芯的第一端与所述第一油口连通，所述阀芯的第二端与所述第二油口连通；
    当所述放油阀内的液压油流向从所述第一油口到所述第二油口时，所述阀芯能够在弹性元件的作用下从所述第二工作位切换到所述第一工作位；
    当所述放油阀内的液压油流向从所述第二油口到所述第一油口时，所述阀芯能够压缩弹性元件并从所述第一工作位切换到所述第二工作位；所述放油阀在所述阀芯工作于所述第二工作位时的流量小于所述阀芯工作于所述第一工作位时的流量。
  2. 根据权利要求1所述的放油阀，其特征在于，在所述阀芯工作于所述第一工作位和所述第二工作位时，所述弹性元件均处于压缩状态，且所述弹性元件在所述阀芯工作于所述第一工作位时的弹力小于所述阀芯工作于所述第二工作位时的弹力。
  3. 根据权利要求1所述的放油阀，其特征在于，所述阀体上设有限位件，当所述阀芯工作于所述第一工作位时所述限位件阻止所述阀芯向远离所述第二工作位的方向移动。
  4. 根据权利要求1-3任一项所述的放油阀，其特征在于，所述阀体内设有油路，所述阀芯的第一端与所述阀体之间形成第一背腔，所述弹性元件设置于所述第一背腔内，所述油路连通所述第一背腔和所述第一油口形成第一反馈油路；
    所述阀芯的第二端设有腔体，所述腔体与所述第二油口相连通，所述腔体的侧壁设有第一油孔，所述腔体与所述第一油口通过所述第一油孔相连通；所述阀芯工作于所述第一工作位时所述第一油孔的开度大于所述阀芯工作于所述第二工作位时所述第一油孔的开度。
  5. 根据权利要求4所述的放油阀，其特征在于，还包括阻尼元件，所述阻尼元件设置于所述第一反馈油路上。
  6. 根据权利要求5所述的放油阀，其特征在于，所述阻尼元件为阻尼孔、阻尼器和电控比例流量阀中的任一种。
  7. 根据权利要求6所述的放油阀，其特征在于，所述阻尼器为可调式阻尼器。
  8. 根据权利要求4所述的放油阀，其特征在于，所述阀体包括阀座和阀套，所述第一油口和所述第二油口均设置于所述阀座，所述阀座设有阀芯腔，所述阀套固定于所述阀芯腔内，所述阀芯可滑动设置于所述阀套内；所述阀套的侧壁上设有第二油孔，所述第二油孔连通所述第一油口和所述第一油孔。
  9. 根据权利要求8所述的放油阀，其特征在于，所述第一背腔形成于所述阀芯的第一端和所述阀套的第一端之间，所述阀套上设有阻尼孔，所述阻尼孔连通所述第一背腔和所述油路。
  10. 根据权利要求8所述的放油阀，其特征在于，所述阀芯腔的内侧面设有第一环形导流槽，所述阀套的内侧面设有第二环形导流槽，所述第一油口、所述第一环形导流槽、所述第二油孔、所述第二环形导流槽和所述第一油孔依次连通；
    所述第一油孔包括沿所述阀芯的周向分布于所述腔体侧壁的多个第一通孔，所述第二油孔包括沿所述阀套的周向分布于所述阀套侧壁的多个第二通孔。
  11. 根据权利要求4所述的放油阀，其特征在于，所述第一油孔包括沿所述阀芯的轴向分布于所述腔体侧壁有多个第一通孔，且靠近所述阀芯的第二端的所述第一通孔的孔径小于远离所述阀芯的第二端的所述第一通孔的孔径。
  12. 根据权利要求1-3任一项所述的放油阀，其特征在于，所述弹性元件为复位弹簧。
  13. 一种蓄能装置，其特征在于，包括蓄能器和如权利要求1-12任一项所述的放油阀，所述放油阀安装于所述蓄能器的出油口，所述蓄能器的出油口与所述第二油口相连通。
  14. 一种液压系统，其特征在于，包括油泵、执行元件、蓄能器和如权利要求1-12任一项所述的放油阀，所述第一油口分别与所述油泵的出油口和所述执行元件的工作油口相连通，所述第二油口与所述蓄能器的出油口相连 通；
    或者，所述液压系统包括油泵、执行元件和如权利要求13所述的蓄能装置。
  15. 一种作业机械，其特征在于，包括如权利要求14所述的液压系统。
PCT/CN2022/073532 2021-09-29 2022-01-24 放油阀、蓄能装置、液压系统和作业机械 WO2023050660A1 (zh)

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