EP3095752A1 - Oil returning structure - Google Patents

Oil returning structure Download PDF

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Publication number
EP3095752A1
EP3095752A1 EP15730039.3A EP15730039A EP3095752A1 EP 3095752 A1 EP3095752 A1 EP 3095752A1 EP 15730039 A EP15730039 A EP 15730039A EP 3095752 A1 EP3095752 A1 EP 3095752A1
Authority
EP
European Patent Office
Prior art keywords
communicating
cavity
liquid
blocking ball
base
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP15730039.3A
Other languages
German (de)
French (fr)
Other versions
EP3095752A4 (en
EP3095752B1 (en
Inventor
Jiang Chen
Junxue YE
Jingfang Wang
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Changshu Tongrun Auto Accessory Co Ltd
Original Assignee
Changshu Tongrun Auto Accessory 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
Application filed by Changshu Tongrun Auto Accessory Co Ltd filed Critical Changshu Tongrun Auto Accessory Co Ltd
Priority to PL15730039T priority Critical patent/PL3095752T3/en
Priority claimed from PCT/CN2015/076874 external-priority patent/WO2016149968A1/en
Publication of EP3095752A1 publication Critical patent/EP3095752A1/en
Publication of EP3095752A4 publication Critical patent/EP3095752A4/en
Application granted granted Critical
Publication of EP3095752B1 publication Critical patent/EP3095752B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/24Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
    • B66F3/25Constructional features
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/202Externally-operated valves mounted in or on the actuator
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/22Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B20/00Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F3/00Devices, e.g. jacks, adapted for uninterrupted lifting of loads
    • B66F3/24Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
    • B66F3/25Constructional features
    • B66F3/42Constructional features with self-contained pumps, e.g. actuated by hand
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • F15B15/1428Cylinders
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/149Fluid interconnections, e.g. fluid connectors, passages
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/75Control of speed of the output member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/76Control of force or torque of the output member
    • F15B2211/761Control of a negative load, i.e. of a load generating hydraulic energy

Definitions

  • the present invention relates to an oil return mechanism.
  • a jack is generally configured with an oil return mechanism.
  • a conventional oil return mechanism includes a liquid storing cavity, a liquid returning cavity, and a communicating cavity communicating between the liquid storing cavity and the liquid returning cavity.
  • the communicating cavity is configured with a control switch for selectively conducting the on-off control of the communicating cavity.
  • a speed of a fluid flowing from the liquid returning cavity to the communicating cavity has a direct impact on a descending speed of the jack in operation.
  • the control switch is on, the speed of the fluid flowing from the liquid returning cavity to the communicating cavity remains stable, and thus the jack descends rapidly either in a no load condition or in a load condition, which may result in accidents, for instance, a lifting load rapidly falling down from the operating jack to hurt an operator.
  • the conventional oil return mechanism is configured with a speed regulating device for regulating the speed of the fluid flowing from the liquid returning cavity to the communicating cavity in accordance with the different operation condition of the jack.
  • the expensive speed regulating device adds significant cost to the oil return mechanism, and thus the oil return mechanism fails to satisfy industrial requires.
  • the present invention provides an oil return mechanism which can regulate a speed of a fluid flowing from a liquid returning cavity to the communicating cavity, and reduce costs efficiently.
  • An oil return mechanism comprising:
  • the control switch includes a second blocking ball mounted in the base and a valve rod; the valve rod is adapted for pushing the second blocking ball in a sealing position for sealing the second communicating opening; and the valve rod is threadly coupled to the base.
  • An end of the elastic member is mounted in the communicating cavity, and the other end of the elastic member is positioned against the first blocking ball.
  • the first blocking ball moves between the blocking position and the open position under the cooperative control of an elastic force of the elastic member and a hydraulic pressure of the liquid in the liquid returning cavity.
  • the open position is positioned in an end of the liquid returning cavity adjacent to the first communicating opening, and a diameter of the end of the liquid returning cavity is larger than the one of the first blocking ball.
  • the elastic force generated by the elastic member acts on the first blocking ball from the blocking position to the open position.
  • the elastic member is a spring.
  • a plurality of liquid guiding gaps is formed between the first blocking ball and the communicating portion of the base.
  • an oil return mechanism includes a base 1, a control switch; a first blocking ball 2 mounted in the base 1, an elastic member 3 mounted between the first blocking ball 2 and the base 1.
  • the base 1 has a liquid storing cavity 11, a liquid returning cavity 12, a communicating cavity 13, a first communicating opening 14 communicating between the liquid returning cavity 12 and the communicating cavity 13, and a second communicating opening communicating between the communicating cavity 13 and the liquid storing cavity 11.
  • the control switch is adapted for controlling the second communicating opening open or closed so that the communicating cavity 13 and the liquid storing cavity 11 are connected or separated.
  • the first blocking ball 2 moves between a blocking position and an open position with an external force.
  • the whole first communicating opening 14 is open, and thus a fluid flows from the liquid returning cavity 12 to the communicating cavity 13.
  • the first communicating opening 14 is positioned in a communicating portion of the base 1.
  • one or more liquid guiding gaps 15 are formed between the first blocking ball 2 and the communicating portion of the base 1.
  • the liquid guiding gap 15 communicates between the liquid returning cavity 12 and the communicating cavity 13.
  • the first blocking ball 2 In use, when the first blocking ball 2 is in an open position, a fluid flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14. When the first blocking ball 2 is in the blocking position, the fluid flows from the liquid returning cavity 12 to the communicating cavity 13 through the liquid guiding gap 15, which can reduce the amount of the flowing liquid. Therefore, the speed of the fluid flowing from the liquid returning cavity 12 to the communicating cavity 13 can be regulated by the movement of the first blocking ball 2. When the jack is in operation and no-load, the first blocking ball 2 is in the open position, and the liquid flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14, so that the jack slows down rapidly.
  • the liquid guiding gap 15 can reduce the amount of the flowing liquid, thus the fluid slows down, and the jack descends slowly.
  • the present invention has the advantages of simple structure, convenient manufacture and great reduction of cost.
  • the liquid guiding gap 15 has an advantage of avoiding clogging.
  • the liquid guiding gap 15 can be manufactured as follows. A sealing surface in the communicating portion is made firstly, and the sealing surface matches the first blocking ball 2. Secondly, a recess in the sealing surface is made so that the first communicating opening 14 is not completely sealed when the first blocking ball is in the blocking position. In other embodiments, the first blocking ball 2 may be irregular shape so that the first communicating opening 14 is not completely sealed.
  • the size of the liquid guiding gap 15 has a direct impact on the speed of the returning fluid in the blocking position, and can be set as requirements. The amount of the liquid guiding gap 15 can be set as requirements, such as one or more.
  • an end of the elastic member 3 is mounted in the communicating cavity 3, and the other end of the elastic member 3 is positioned against the first blocking ball 2, which is convenient for assembling.
  • the first blocking ball 2 moves between the blocking position and the open position with the external force, such as hydraulic pressure.
  • the first blocking ball 2 moves between the blocking position and the open position under the cooperative control of an elastic force of the elastic member 3 and the hydraulic pressure of the liquid in the liquid returning cavity 12.
  • the open position is positioned in an end of the liquid returning cavity 12 adjacent to the first communicating opening 14, and a diameter of the end of the liquid returning cavity 12 is larger than the one of the first blocking ball 2.
  • the elastic force generated by the elastic member acts on the first blocking ball 2 from the blocking position to the open position. That is to say, the elastic member 3 is in a compressed state when the first blocking ball 2 is in the blocking position. The elastic member 3 generates a force on the first blocking ball 2 towards the open position when the elastic member 3 is released. The liquid in the liquid returning cavity 12 generates a force on the first blocking ball 2 from the open position to the blocking position.
  • the elastic member 3 may be a spring or an elastic ring.
  • the control switch includes a second blocking ball 4 mounted in the base 1 and a valve rod 5.
  • the valve rod 5 is adapted for pushing the second blocking ball 4 in a sealing position for sealing the second communicating opening.
  • the valve rod 5 is threadly coupled to the base 1. The simplification of the control switch can reduce costs.
  • the valve rod 5 pushes the second blocking ball 4 in the sealing position so that the second communicating opening is sealed.
  • the valve rod 5 is screwed to release the second blocking ball 4, and the fluid pushes the second blocking ball 4 upwards so that the second communicating opening is open.
  • the liquid returning cavity 12 is generally configured with a piston.
  • the moving speed of the piston is controlled by the fluid flowing from the liquid returning cavity 12, and thus the descending speed of the jack is controlled by the piston.
  • the valve rod 5 is screwed to release the second blocking ball 4.
  • the first blocking ball 2 moves to the open position when the elastic force of the spring is larger than the hydraulic pressure of the hydraulic oil in the liquid returning cavity 12.
  • the hydraulic oil flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14 (referred to the arrow direction in FIG. 2 ), and further goes through the communicating cavity 13 to push the second blocking ball 4 upwards, and then flows into the liquid storing cavity 11.
  • the valve rod 5 is screwed to release the blocking ball 4.
  • the first blocking ball 2 is in blocking position when the elastic force of the spring is smaller than the hydraulic pressure of the hydraulic oil in the liquid returning cavity 12.
  • the hydraulic oil flows into the communicating cavity 13 through the liquid guiding gap 15 (referred to the arrow direction in FIG. 3 ), and pushes the second blocking ball 4 upwards, and then flows into the liquid returning cavity 11. Therefore, the jack slows down.
  • FIG. 4 shows a construction schematic diagram of a second embodiment of the present invention.
  • the difference between the FIG. 4 and the FIG. 1 is the installation how the valve rod 5 coupled to the base 1.
  • the valve rod 5 is vertically and threadly coupled to the base 1.
  • the valve rod 5 is obliquely and threadly coupled to the base 1.
  • the installation how the valve rod 5 coupled to the base 1 is not limited only if the valve 5 can push the second blocking ball 4.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Structural Engineering (AREA)
  • Check Valves (AREA)

Abstract

An oil return mechanism includes a base, a control switch, a first blocking ball mounted in the base, an elastic member mounted between the first blocking ball and the base. The base has a liquid storing cavity, a liquid returning cavity, a communicating cavity, a first communicating opening communicating between the liquid returning cavity and the communicating cavity, and a second communicating opening communicating between the communicating cavity and the liquid storing cavity. The control switch is adapted for controlling the second communicating opening open or closed so that the communicating cavity and the liquid storing cavity are connected or separated. The first blocking ball moves between a blocking position and an open position. The first communicating opening is positioned in a communicating portion of the base. When the first blocking ball is in the blocking position, one or more liquid guiding gaps are formed between the first blocking ball and an inner wall of the communicating portion of the base. The liquid guiding gap communicates between the liquid returning cavity and the communicating cavity. The present invention can regulate a speed of a fluid flowing from the liquid returning cavity to the communicating cavity, and has the advantages of simple structure and great reduction of cost.

Description

    TECHNICAL FIELD
  • The present invention relates to an oil return mechanism.
  • BACKGROUND
  • A jack is generally configured with an oil return mechanism. A conventional oil return mechanism includes a liquid storing cavity, a liquid returning cavity, and a communicating cavity communicating between the liquid storing cavity and the liquid returning cavity. The communicating cavity is configured with a control switch for selectively conducting the on-off control of the communicating cavity. A speed of a fluid flowing from the liquid returning cavity to the communicating cavity has a direct impact on a descending speed of the jack in operation. However, when the control switch is on, the speed of the fluid flowing from the liquid returning cavity to the communicating cavity remains stable, and thus the jack descends rapidly either in a no load condition or in a load condition, which may result in accidents, for instance, a lifting load rapidly falling down from the operating jack to hurt an operator. Therefore, the conventional oil return mechanism is configured with a speed regulating device for regulating the speed of the fluid flowing from the liquid returning cavity to the communicating cavity in accordance with the different operation condition of the jack. However, the expensive speed regulating device adds significant cost to the oil return mechanism, and thus the oil return mechanism fails to satisfy industrial requires.
  • SUMMARY OF THE INVENTION
  • To overcome the defects described above, the present invention provides an oil return mechanism which can regulate a speed of a fluid flowing from a liquid returning cavity to the communicating cavity, and reduce costs efficiently.
  • Some embodiments of the present invention refer to:
  • An oil return mechanism, comprising:
    • a base, a control switch, a first blocking ball mounted in the base, an elastic member mounted between the first blocking ball and the base; wherein the base has a liquid storing cavity, a liquid returning cavity, a communicating cavity, a first communicating opening communicating between the liquid returning cavity and the communicating cavity, and a second communicating opening communicating between the communicating cavity and the liquid storing cavity; the control switch is adapted for controlling the second communicating opening open or closed so that the communicating cavity and the liquid storing cavity are connected or separated; the first blocking ball moves between a blocking position and an open position with an external force; when the first blocking ball is in the open position, the whole first communicating opening is open, and thus a fluid flows from the liquid returning cavity to the communicating cavity; the first communicating opening is positioned in a communicating portion of the base; when the first blocking ball is in the blocking position, one or more liquid guiding gaps are formed between the first blocking ball and the communicating portion of the base; and the liquid guiding gap communicates between the liquid returning cavity and the communicating cavity.
  • The control switch includes a second blocking ball mounted in the base and a valve rod; the valve rod is adapted for pushing the second blocking ball in a sealing position for sealing the second communicating opening; and the valve rod is threadly coupled to the base.
  • An end of the elastic member is mounted in the communicating cavity, and the other end of the elastic member is positioned against the first blocking ball.
  • The first blocking ball moves between the blocking position and the open position under the cooperative control of an elastic force of the elastic member and a hydraulic pressure of the liquid in the liquid returning cavity.
  • The open position is positioned in an end of the liquid returning cavity adjacent to the first communicating opening, and a diameter of the end of the liquid returning cavity is larger than the one of the first blocking ball.
  • The elastic force generated by the elastic member acts on the first blocking ball from the blocking position to the open position.
  • The elastic member is a spring.
  • A plurality of liquid guiding gaps is formed between the first blocking ball and the communicating portion of the base.
  • Beneficial effects of the present invention are as follows:
    • In use, when the first blocking ball moves to the open position or the blocking position, the fluid can flow to the communicating cavity through the second communicating cavity or the liquid guiding gap, to reduce the amount of the flowing liquid, and thus regulate the speed of the fluid flowing from the liquid returning cavity to the communicating cavity. Moreover, the present invention has the advantages of simple structure, convenient manufacture and great reduction of cost. The liquid guiding gap formed between the first blocking ball and an inner wall of the communicating portion has an advantage of avoiding clogging.
    BRIEF DESCRIPTION OF THE DRAWINGS
    • FIG. 1 is a construction schematic diagram of the present invention;
    • FIG. 2 shows a first blocking ball positioned in an open position.
    • FIG. 3 shows the second blocking ball positioned in a blocking position.
    • FIG. 4 is a construction schematic diagram of another embodiment of the present invention.
    Reference numbers in the drawings are as follow:
    • 1, base; 11, liquid storing cavity; 12, liquid returning cavity; 13, communicating cavity; 14, first communicating opening; 15, liquid guiding gap; 2, first blocking ball; 3, elastic member; 4, second blocking ball; and 5, valve rod.
    DETAILED DESCRIPTION OF THE PREFERED EMBODIMENTS
  • Referring to the FIG. 1 to FIG. 3, an oil return mechanism includes a base 1, a control switch; a first blocking ball 2 mounted in the base 1, an elastic member 3 mounted between the first blocking ball 2 and the base 1. The base 1 has a liquid storing cavity 11, a liquid returning cavity 12, a communicating cavity 13, a first communicating opening 14 communicating between the liquid returning cavity 12 and the communicating cavity 13, and a second communicating opening communicating between the communicating cavity 13 and the liquid storing cavity 11. The control switch is adapted for controlling the second communicating opening open or closed so that the communicating cavity 13 and the liquid storing cavity 11 are connected or separated. The first blocking ball 2 moves between a blocking position and an open position with an external force. When the first blocking ball 2 is in the open position, the whole first communicating opening 14 is open, and thus a fluid flows from the liquid returning cavity 12 to the communicating cavity 13. The first communicating opening 14 is positioned in a communicating portion of the base 1. When the first blocking ball 2 is in the blocking position, one or more liquid guiding gaps 15 are formed between the first blocking ball 2 and the communicating portion of the base 1. The liquid guiding gap 15 communicates between the liquid returning cavity 12 and the communicating cavity 13.
  • In use, when the first blocking ball 2 is in an open position, a fluid flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14. When the first blocking ball 2 is in the blocking position, the fluid flows from the liquid returning cavity 12 to the communicating cavity 13 through the liquid guiding gap 15, which can reduce the amount of the flowing liquid. Therefore, the speed of the fluid flowing from the liquid returning cavity 12 to the communicating cavity 13 can be regulated by the movement of the first blocking ball 2. When the jack is in operation and no-load, the first blocking ball 2 is in the open position, and the liquid flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14, so that the jack slows down rapidly. When the jack is on load, the first blocking ball 2 is in the blocking position; the fluid can only flows to the communicating cavity 13 through the liquid guiding gap 15. The liquid guiding gap 15 can reduce the amount of the flowing liquid, thus the fluid slows down, and the jack descends slowly. The present invention has the advantages of simple structure, convenient manufacture and great reduction of cost. The liquid guiding gap 15 has an advantage of avoiding clogging.
  • The liquid guiding gap 15 can be manufactured as follows. A sealing surface in the communicating portion is made firstly, and the sealing surface matches the first blocking ball 2. Secondly, a recess in the sealing surface is made so that the first communicating opening 14 is not completely sealed when the first blocking ball is in the blocking position. In other embodiments, the first blocking ball 2 may be irregular shape so that the first communicating opening 14 is not completely sealed. The size of the liquid guiding gap 15 has a direct impact on the speed of the returning fluid in the blocking position, and can be set as requirements. The amount of the liquid guiding gap 15 can be set as requirements, such as one or more.
  • Specifically, an end of the elastic member 3 is mounted in the communicating cavity 3, and the other end of the elastic member 3 is positioned against the first blocking ball 2, which is convenient for assembling.
  • The first blocking ball 2 moves between the blocking position and the open position with the external force, such as hydraulic pressure. Preferably, the first blocking ball 2 moves between the blocking position and the open position under the cooperative control of an elastic force of the elastic member 3 and the hydraulic pressure of the liquid in the liquid returning cavity 12. Specifically, the open position is positioned in an end of the liquid returning cavity 12 adjacent to the first communicating opening 14, and a diameter of the end of the liquid returning cavity 12 is larger than the one of the first blocking ball 2.
  • The elastic force generated by the elastic member acts on the first blocking ball 2 from the blocking position to the open position. That is to say, the elastic member 3 is in a compressed state when the first blocking ball 2 is in the blocking position. The elastic member 3 generates a force on the first blocking ball 2 towards the open position when the elastic member 3 is released. The liquid in the liquid returning cavity 12 generates a force on the first blocking ball 2 from the open position to the blocking position.
  • Preferably, the elastic member 3 may be a spring or an elastic ring.
  • The control switch includes a second blocking ball 4 mounted in the base 1 and a valve rod 5. The valve rod 5 is adapted for pushing the second blocking ball 4 in a sealing position for sealing the second communicating opening. The valve rod 5 is threadly coupled to the base 1. The simplification of the control switch can reduce costs. In use, the valve rod 5 pushes the second blocking ball 4 in the sealing position so that the second communicating opening is sealed. The valve rod 5 is screwed to release the second blocking ball 4, and the fluid pushes the second blocking ball 4 upwards so that the second communicating opening is open.
  • In actual design, the liquid returning cavity 12 is generally configured with a piston. The moving speed of the piston is controlled by the fluid flowing from the liquid returning cavity 12, and thus the descending speed of the jack is controlled by the piston.
  • In actual use, when the jack is no load, the valve rod 5 is screwed to release the second blocking ball 4. The first blocking ball 2 moves to the open position when the elastic force of the spring is larger than the hydraulic pressure of the hydraulic oil in the liquid returning cavity 12. The hydraulic oil flows from the liquid returning cavity 12 to the communicating cavity 13 through the first communicating opening 14 (referred to the arrow direction in FIG. 2), and further goes through the communicating cavity 13 to push the second blocking ball 4 upwards, and then flows into the liquid storing cavity 11. When the jack is on load, the valve rod 5 is screwed to release the blocking ball 4. The first blocking ball 2 is in blocking position when the elastic force of the spring is smaller than the hydraulic pressure of the hydraulic oil in the liquid returning cavity 12. The hydraulic oil flows into the communicating cavity 13 through the liquid guiding gap 15 (referred to the arrow direction in FIG. 3), and pushes the second blocking ball 4 upwards, and then flows into the liquid returning cavity 11. Therefore, the jack slows down.
  • Fig. 4 shows a construction schematic diagram of a second embodiment of the present invention. The difference between the FIG. 4 and the FIG. 1 is the installation how the valve rod 5 coupled to the base 1. In FIG. 1, the valve rod 5 is vertically and threadly coupled to the base 1. In FIG. 4, the valve rod 5 is obliquely and threadly coupled to the base 1. The installation how the valve rod 5 coupled to the base 1 is not limited only if the valve 5 can push the second blocking ball 4.
  • Various modifications could be made to the embodiments by those of ordinary skill in the art without departing from the true spirit and scope of the disclosure. And those modified embodiments are covered by the claims of the disclosure.

Claims (8)

  1. An oil return mechanism, comprising:
    a base, a control switch, a first blocking ball mounted in the base, an elastic member mounted between the first blocking ball and the base; wherein the base has a liquid storing cavity, a liquid returning cavity, a communicating cavity, a first communicating opening communicating between the liquid returning cavity and the communicating cavity, and a second communicating opening communicating between the communicating cavity and the liquid storing cavity; the control switch is adapted for controlling the second communicating opening open or closed so that the communicating cavity and the liquid storing cavity are connected or separated; the first blocking ball moves between a blocking position and an open position with an external force; when the first blocking ball is in the open position, the whole first communicating opening is open, and thus a fluid flows from the liquid returning cavity to the communicating cavity; the first communicating opening is positioned in a communicating portion of the base; when the first blocking ball is in the blocking position, one or more liquid guiding gaps are formed between the first blocking ball and the communicating portion of the base; and the liquid guiding gap communicates between the liquid returning cavity and the communicating cavity.
  2. The oil return mechanism of claim 1, wherein the control switch includes a second blocking ball mounted in the base and a valve rod; the valve rod is adapted for pushing the second blocking ball in a sealing position for sealing the second communicating opening; and the valve rod is threadly coupled to the base.
  3. The oil return mechanism of claim 1, wherein an end of the elastic member is mounted in the communicating cavity, and the other end of the elastic member is positioned against the first blocking ball.
  4. The oil return mechanism of claim 1, wherein the first blocking ball moves between the blocking position and the open position under the cooperative control of an elastic force of the elastic member and a hydraulic pressure of the liquid in the liquid returning cavity.
  5. The oil return mechanism of claim 4, wherein the open position is positioned in an end of the liquid returning cavity adjacent to the first communicating opening, and a diameter of the end of the liquid returning cavity is larger than the one of the first blocking ball.
  6. The oil return mechanism of claim 4 or 5, wherein the elastic force generated by the elastic member acts on the first blocking ball from the blocking position to the open position.
  7. The oil return mechanism of claim 1, wherein the elastic member is a spring.
  8. The oil return mechanism of claim 1, wherein a plurality of liquid guiding gaps is formed between the first blocking ball and the communicating portion of the base.
EP15730039.3A 2015-03-23 2015-04-17 Oil returning structure Active EP3095752B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PL15730039T PL3095752T3 (en) 2015-03-23 2015-04-17 Oil returning structure

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201511278517 2015-03-23
PCT/CN2015/076874 WO2016149968A1 (en) 2015-03-23 2015-04-17 Oil returning structure

Publications (3)

Publication Number Publication Date
EP3095752A1 true EP3095752A1 (en) 2016-11-23
EP3095752A4 EP3095752A4 (en) 2017-02-22
EP3095752B1 EP3095752B1 (en) 2021-02-17

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EP15730039.3A Active EP3095752B1 (en) 2015-03-23 2015-04-17 Oil returning structure

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EP (1) EP3095752B1 (en)
HU (1) HUE054569T2 (en)
PL (1) PL3095752T3 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4169851A1 (en) 2021-10-19 2023-04-26 Daw Se Container system, protective screen, container and conveyor system

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1468956A1 (en) * 2003-04-14 2004-10-20 Shinn Fu Corporation Lifting jack comprising a lower control system regulating the flow rate of lifting jack oil

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EP3095752A4 (en) 2017-02-22
PL3095752T3 (en) 2021-08-16
EP3095752B1 (en) 2021-02-17
HUE054569T2 (en) 2021-09-28

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