CN110748528A - Control valve for oil cylinder - Google Patents

Control valve for oil cylinder Download PDF

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Publication number
CN110748528A
CN110748528A CN201911033018.0A CN201911033018A CN110748528A CN 110748528 A CN110748528 A CN 110748528A CN 201911033018 A CN201911033018 A CN 201911033018A CN 110748528 A CN110748528 A CN 110748528A
Authority
CN
China
Prior art keywords
valve
hole
oil
plug
spring
Prior art date
Application number
CN201911033018.0A
Other languages
Chinese (zh)
Inventor
黄洪刚
Original Assignee
黄洪刚
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 黄洪刚 filed Critical 黄洪刚
Priority to CN201911033018.0A priority Critical patent/CN110748528A/en
Publication of CN110748528A publication Critical patent/CN110748528A/en

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Classifications

    • 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
    • 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
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/202Externally-operated valves mounted in or on the actuator

Abstract

The invention discloses a control valve for an oil cylinder, which comprises a valve body, a valve core, a spring and a plug, and is characterized in that a valve hole is arranged in the valve body, the valve body is sequentially provided with a first valve hole, a second valve hole and a third valve hole which are communicated with the valve hole from top to bottom, the valve core is connected in the valve hole in a sliding manner, the plug is fixedly arranged at the opening of the valve hole, and the spring is positioned between the plug and the valve core; the valve core is provided with a first oil port and a second oil port, an oil hole is formed in the valve core, and a sixth communicating hole is formed in the circumferential side face of the valve core; a shuttle valve rod is connected in the oil hole in a sliding mode, a first shuttle valve body is arranged at one end of the shuttle valve rod, a second shuttle valve body is arranged at the other end of the shuttle valve rod, and a communicating groove is formed in the side face of the outer circumference of the shuttle valve rod; this a control valve for hydro-cylinder, not only simple structure through two hydraulic fluid ports moreover, makes the pipeline of system more succinct, and carries out the switching of operating mode through pressure variation, makes control simpler.

Description

Control valve for oil cylinder

Technical Field

The invention belongs to the technical field of hydraulic valves, and particularly relates to a control valve for an oil cylinder.

Background

The invention discloses a hydraulic cylinder, which is characterized in that a plurality of hydraulic valves are adopted for controlling, so that the manufacturing cost of the hydraulic cylinder is higher, the invention patent with the patent publication number of CN 101929486A and the name of a composite oil cylinder provides a technical scheme capable of realizing the functions of fast forward, fast backward, work speed and the like of the oil cylinder, but the design realizes the action requirements of fast forward, fast backward and work speed of the oil cylinder by arranging a small oil cylinder in a piston rod and controlling through the cooperation of four oil ports, and the hydraulic cylinder is complicated in connecting a system pipeline during use and complicated in control work and is not beneficial to the use of the oil cylinder.

Disclosure of Invention

Technical problem to be solved

The invention aims to provide a control valve for an oil cylinder, which is simple in structure, enables a pipeline of a system to be simpler through two oil ports, and enables the control to be simpler by switching working conditions through pressure change.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: a control valve for an oil cylinder comprises a valve body, a valve core, a spring and a plug, wherein a valve hole is formed in the valve body, the valve body is sequentially provided with a first valve hole, a second valve hole and a third valve hole which are communicated with the valve hole from top to bottom, the valve core is connected in the valve hole in a sliding mode, the plug is fixedly installed at an opening of the valve hole, and the spring is located between the plug and the valve core and used for forcing the valve core to press the third valve hole; the valve core is provided with a first oil port communicated with the first valve hole at one end close to the spring, a second oil port communicated with the third valve hole at one end far away from the spring, an oil hole used for communicating the first oil port with the second oil port is formed in the valve core, and a sixth communication hole communicated with the oil hole is formed in the circumferential side surface of the valve core; the shuttle valve comprises an oil hole, a shuttle valve rod is connected in the oil hole in a sliding mode, one end of the shuttle valve rod is provided with a first shuttle valve body used for controlling the opening and closing of a first oil port, the other end of the shuttle valve rod is provided with a second shuttle valve body used for controlling the opening and closing of a second oil port, and a communicating groove is formed in the side face of the outer circumference of the shuttle valve rod along the axial direction of.

In a further technical scheme, the plug is internally threaded with an adjusting screw rod, one end of the adjusting screw rod extends into the valve hole, and the adjusting screw rod is used for adjusting the pretightening force of the spring; one end of the adjusting screw rod extending into the valve hole is provided with a plug body connected in the plug in a sliding mode, and the spring is located between the plug body and the valve core.

In a further technical scheme, the adjusting screw is in threaded connection with a lock nut, and the lock nut is positioned on the outer side of the plug.

In a further technical scheme, the plug body is provided with a positioning convex column at the center of the end face facing the spring, the positioning convex column is sleeved with a gasket, and one end of the spring is abutted against the gasket.

In a further technical scheme, a first annular groove is formed in the side face of the outer circumference of the plug body, and a first sealing ring is arranged in the first annular groove.

In a further technical scheme, a second annular groove is formed in the outer circumferential side face of the valve body between the first valve hole and the second valve hole, a third annular groove is formed between the second valve hole and the third valve hole, a second sealing ring is arranged in the second annular groove, and a third sealing ring is arranged in the third annular groove.

(III) advantageous effects

Compared with the prior art, the technical scheme of the invention has the following advantages:

the flow direction of the hydraulic oil is controlled by the control valve so as to control the oil cylinder to meet different working condition requirements of fast forward, fast backward, working speed and the like, and the control valve is convenient and ingenious; the control valve switches working conditions through pressure change, so that the control is simpler.

Drawings

FIG. 1 is a cross-sectional view of the present invention applied to a cylinder;

FIG. 2 is a cross-sectional view of the control valve of the present invention;

fig. 3 is an enlarged structural view at C in fig. 2.

Detailed Description

Referring to fig. 1-3, a control valve for an oil cylinder, where the control valve 3 includes a valve body 7, a valve core 5, a spring 8, and a plug 16, a valve hole 71 with an open upper end is formed in the valve body 7, the valve body 7 is sequentially provided with a first valve hole 7c, a second valve hole 7b, and a third valve hole 7a communicated with the valve hole 71 from top to bottom, the valve core 5 is slidably connected in the valve hole 71, the plug 16 is fixedly installed at an opening of the valve hole 71, and the spring 8 is located between the plug 16 and the valve core 5 to force the valve core 5 to press the third valve hole 7 a; a first oil port 51 communicated with the first valve hole 7c is formed at one end, close to the spring 8, of the valve core 5, a second oil port 52 communicated with the third valve hole 7a is formed at one end, far away from the spring 8, of the valve core 5, an oil hole 53 for communicating the first oil port 51 with the second oil port 52 is formed in the valve core 5, and a sixth communication hole 5a communicated with the oil hole 53 is formed in the circumferential side surface of the valve core 5; a shuttle valve rod 6 is connected in the oil hole 53 in a sliding manner, one end of the shuttle valve rod 6 is provided with a first shuttle valve body 61 for controlling the opening and closing of the first oil hole 51, the other end of the shuttle valve rod 6 is provided with a second shuttle valve body 62 for controlling the opening and closing of the second oil hole 52, and a communication groove 6c is formed on the side surface of the outer circumference of the shuttle valve rod 6 along the axial direction thereof.

The inner thread of the plug 16 is connected with an adjusting screw rod 31 with one end extending into the valve hole 71, and the adjusting screw rod 31 is used for adjusting the pretightening force of the spring 8; one end of the adjusting screw 31 extending into the valve hole 71 is provided with a plug body 32 connected in a sliding manner in the plug 16, and the spring 8 is positioned between the plug body 32 and the valve core 5. The adjusting screw 31 is connected with a lock nut 33 through threads, and the lock nut 33 is positioned on the outer side of the plug 16. The plug body 32 is provided with a positioning convex column 34 at the central position of the end surface facing the spring 8, a washer 35 is sleeved on the positioning convex column 34, and one end of the spring 8 is abutted against the washer 35. A first annular groove 32a is formed in the outer circumferential side surface of the plug body 32, and a first sealing ring 36 is arranged in the first annular groove 32 a. A second annular groove 7d is formed in the outer circumferential side surface of the valve body 7 between the first valve hole 7c and the second valve hole 7b, a third annular groove 7e is formed between the second valve hole 7b and the third valve hole 7a, a second sealing ring 37 is arranged in the second annular groove 7d, and a third sealing ring 38 is arranged in the third annular groove 7 e.

The oil cylinder is required to be arranged on an oil cylinder when in use, wherein the oil cylinder comprises a cylinder body 2 with openings at two ends, an upper end cover 9 is fixedly arranged at the opening of the upper end of the cylinder body 2, and a lower end cover 4 is fixedly arranged at the opening of the lower end; the cylinder body 2 is connected with a piston body 1 in a sliding manner, a piston rod 11 penetrating through an upper end cover 9 is arranged on the piston body 1, and the piston rod 11 is connected in the upper end cover 9 in a sliding manner; a rodless cavity 2a is formed between the piston body 1 and the lower end cover 4 in the cylinder body 2, and a rod cavity 2b is formed between the piston body 1 and the upper end cover 9; the side surface of the cylinder body 2 is provided with an air hole 2c communicated with the rod cavity 2 b; the lower end of the piston body 1 is provided with a piston hole 10 extending upwards into a piston rod 11, the lower end opening of the piston hole 10 is in threaded connection with a piston ring 12, the lower end cover 4 is provided with a convex column 41 extending into the piston hole 10 through the piston ring 12 upwards along the vertical direction, the convex column 41 is in sliding connection with the inner ring of the piston ring 12, and the outer circumferential side surface of the convex column 41 is provided with a convex edge 42 in sliding connection with the piston hole 10 at a position close to the upper end of the convex column 41; a first oil chamber 4b is formed between the flange 42 and the piston ring 12 in the piston hole 10, and a second oil chamber 4a is formed between the flange 42 and the upper end of the piston hole 10; the lower end of the lower end cover 4 is provided with a port A and a port B, and a first communication hole 4d for communicating the port A with the second oil chamber 4a and a second communication hole 4c for communicating the port B with the first oil chamber 4B are arranged in the lower end cover 4 and the convex column 41; the piston rod 11 is provided with a mounting hole 11a on the outer circumferential side surface near the upper end thereof, the valve body 7 of the control valve 3 is inserted into the mounting hole 11a, the first valve hole 7c of the control valve 3 is communicated with the first oil chamber 4b through a third communication hole 1a arranged in the piston rod 11 and the piston body 1, the second valve hole 7b of the control valve 3 is communicated with the rodless chamber 2a through a fourth communication hole 1b arranged in the piston rod 11 and the piston body 1, and the third valve hole 7a of the control valve 3 is communicated with the second oil chamber 4a through a fifth communication hole 1d arranged in the piston rod 11 and the piston body 1.

When the oil cylinder provided with the control valve works, the oil cylinder can work only by connecting the port A and the port B with a system pipeline. When the oil cylinder fast-forwards, firstly, the oil cylinder is in a retracting state, a system pipeline leads hydraulic oil into the oil cylinder from the port A, the hydraulic oil enters the second oil chamber 4a through the port A and the first communication hole 4d, the hydraulic oil leads into the third valve hole 7a of the control valve 3 through the fifth communication hole 1d, due to the relation of liquid flow, the second shuttle valve body 62 closes the second oil port 52, the system pressure is low at the moment, the valve core 5 cannot be pushed to move towards the direction of the plug 16 to open the third valve hole 7a by overcoming the spring 8, meanwhile, the first shuttle valve body 61 opens the first oil port 51 to enable the second valve hole 7B to be communicated with the first valve hole 7c, so that the hydraulic oil pushes the piston rod 11 to extend after entering the second oil chamber 4a, and the hydraulic oil enters the first valve hole 7c through the port B, the second communication hole 4c, the first oil chamber 4B and the third communication hole 1a and then enters the first valve hole, The communication groove 6c, the sixth communication hole 5a, enters the second valve hole 7b and is replenished into the rodless chamber 2a through the fourth communication hole 1b, and the air in the rod chamber 2b is discharged from the air hole 2c to the atmosphere as the piston rod 11 protrudes. In the process, compared with a common oil cylinder with the same cylinder diameter, under the condition of the same inlet flow, the cross section area of the second oil chamber 4a is far smaller than that of the oil cylinder, so that the piston rod 11 extends out more quickly, and the function of fast forwarding is realized.

When the oil cylinder is fast retracted, firstly the oil cylinder is in an extending state, a system pipeline leads hydraulic oil into the oil cylinder from the port B, the hydraulic oil enters the first oil chamber 4B through the port B and the second communication hole 4c, and leads the hydraulic oil into the first valve hole 7c of the control valve 3 through the third communication hole 1a, due to the relation of liquid flow, the first shuttle valve body 61 closes the first oil port 51, the second shuttle valve body 62 opens the second oil port 52, so that the third valve hole 7a is communicated with the third valve hole 7a, the hydraulic oil enters the first oil chamber 4B and pushes the piston rod 11 to retract, the hydraulic oil in the rodless chamber 2a enters the second valve hole 7B through the fourth communication hole 1B, enters the third valve hole 7a through the sixth communication hole 5a, the communication groove 6c and the second communication hole 52, and enters the second oil chamber 4a through the fifth communication hole 1d, and the hydraulic oil entering the second oil chamber 4a passes through the first communication hole 4d, The port A is removed from the oil cylinder, air in the atmosphere is sucked into the rod cavity 2b through the air hole 2c along with the retraction of the piston rod 11, and in the process, compared with a common oil cylinder with the same cylinder diameter, under the condition of the same inlet flow, the retraction speed of the piston rod 11 is higher because the cross section area of the first oil cavity 4b is far smaller than that of the oil cylinder, and the function of quick retraction is realized.

When the oil cylinder works at a working speed, firstly the oil cylinder does work outwards, the system pressure is increased, a system pipeline leads hydraulic oil into the oil cylinder from the port A, the hydraulic oil enters the second oil chamber 4a through the port A and the first communication hole 4d, the hydraulic oil leads into the third valve hole 7a through the fifth communication hole 1d, due to the relation of liquid flow, the second shuttle valve body 62 closes the second oil port 52, the system pressure is higher than the set pressure of the spring 8, the hydraulic oil overcomes the spring 8 to push the valve core 5 to move towards the direction of the plug 16 to open the third valve hole 7a, the sixth communication hole 5a is covered and closed, the second valve hole 7b is not communicated with the first valve hole 7c, the third valve hole 7a is communicated with the second valve hole 7b, the hydraulic oil enters the second oil chamber 4a, then enters the third valve hole 7a through the fifth communication hole 1d, and then enters the rodless chamber 2a through the second valve hole 7b and the fourth communication hole 1b, the air in the rod cavity 2b is discharged into the atmosphere from the air hole 2c along with the extension of the piston rod 11, and the high-pressure oil acts on the cross section of the whole piston body 1 at the moment, and the extension speed of the piston rod 11 is the same as that of a common oil cylinder with the same cylinder diameter; because the area that hydraulic oil used is the cross-sectional area of piston body 1, consequently can realize the full load work under the worker's speed, accomplish the operating mode requirement when the worker is fast.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (6)

1. A control valve for an oil cylinder comprises a valve body, a valve core, a spring and a plug, and is characterized in that a valve hole is formed in the valve body, the valve body is sequentially provided with a first valve hole, a second valve hole and a third valve hole which are communicated with the valve hole from top to bottom, the valve core is connected in the valve hole in a sliding mode, the plug is fixedly arranged at an opening of the valve hole, and the spring is located between the plug and the valve core and used for forcing the valve core to press the third valve hole; the valve core is provided with a first oil port communicated with the first valve hole at one end close to the spring, a second oil port communicated with the third valve hole at one end far away from the spring, an oil hole used for communicating the first oil port with the second oil port is formed in the valve core, and a sixth communication hole communicated with the oil hole is formed in the circumferential side surface of the valve core; the shuttle valve comprises an oil hole, a shuttle valve rod is connected in the oil hole in a sliding mode, one end of the shuttle valve rod is provided with a first shuttle valve body used for controlling the opening and closing of a first oil port, the other end of the shuttle valve rod is provided with a second shuttle valve body used for controlling the opening and closing of a second oil port, and a communicating groove is formed in the side face of the outer circumference of the shuttle valve rod along the axial direction of.
2. The control valve for the oil cylinder as claimed in claim 1, wherein the plug is internally threaded with an adjusting screw rod, one end of the adjusting screw rod extends into the valve hole, and the adjusting screw rod is used for adjusting the pretightening force of the spring; one end of the adjusting screw rod extending into the valve hole is provided with a plug body connected in the plug in a sliding mode, and the spring is located between the plug body and the valve core.
3. The control valve for the oil cylinder as claimed in claim 2, wherein the adjusting screw is threadedly connected with a lock nut, and the lock nut is located at the outer side of the plug.
4. The control valve for the oil cylinder according to claim 2, wherein the plug body is provided with a positioning convex column at the center of the end surface facing the spring, a washer is sleeved on the positioning convex column, and one end of the spring abuts against the washer.
5. The control valve for the oil cylinder as claimed in claim 2, wherein a first annular groove is formed on an outer circumferential side surface of the plug body, and a first sealing ring is provided in the first annular groove.
6. The control valve for the cylinder according to claim 2, wherein a second annular groove is provided on the outer circumferential side of the valve body between the first valve hole and the second valve hole, a third annular groove is provided between the second valve hole and the third valve hole, a second sealing ring is provided in the second annular groove, and a third sealing ring is provided in the third annular groove.
CN201911033018.0A 2019-10-28 2019-10-28 Control valve for oil cylinder CN110748528A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911033018.0A CN110748528A (en) 2019-10-28 2019-10-28 Control valve for oil cylinder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911033018.0A CN110748528A (en) 2019-10-28 2019-10-28 Control valve for oil cylinder

Publications (1)

Publication Number Publication Date
CN110748528A true CN110748528A (en) 2020-02-04

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Family Applications (1)

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CN201911033018.0A CN110748528A (en) 2019-10-28 2019-10-28 Control valve for oil cylinder

Country Status (1)

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CN (1) CN110748528A (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09217847A (en) * 1996-02-14 1997-08-19 Akashi Kikai Seisakusho:Kk Flow control spool valve
CN101000113A (en) * 2006-12-01 2007-07-18 华中科技大学 Middle and high pressure guiding type water pressure reducing valve
CN201057351Y (en) * 2007-07-10 2008-05-07 宁波市三浪润滑元件有限公司 Multifunctional hydraulic controlling valve
CN101644285A (en) * 2009-08-24 2010-02-10 宁波汉商液压有限公司 Counterbalance valve for controlling hydraulic motor
CN101737370A (en) * 2010-01-29 2010-06-16 浙江大学 Fast hydraulic change-over valve
CN101929486A (en) * 2010-08-12 2010-12-29 湖州机床厂有限公司 Composite oil cylinder
US20130061959A1 (en) * 2011-09-13 2013-03-14 Kirt N. Stephens Hydraulic valve with an annular filter element secured by a helical spring
CN203963114U (en) * 2014-07-18 2014-11-26 台州市兴乐水暖器材有限公司 Constant temperature valve core
CN106050775A (en) * 2016-06-11 2016-10-26 宁波文泽机电技术开发有限公司 Pilot control valve of improved structure

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09217847A (en) * 1996-02-14 1997-08-19 Akashi Kikai Seisakusho:Kk Flow control spool valve
CN101000113A (en) * 2006-12-01 2007-07-18 华中科技大学 Middle and high pressure guiding type water pressure reducing valve
CN201057351Y (en) * 2007-07-10 2008-05-07 宁波市三浪润滑元件有限公司 Multifunctional hydraulic controlling valve
CN101644285A (en) * 2009-08-24 2010-02-10 宁波汉商液压有限公司 Counterbalance valve for controlling hydraulic motor
CN101737370A (en) * 2010-01-29 2010-06-16 浙江大学 Fast hydraulic change-over valve
CN101929486A (en) * 2010-08-12 2010-12-29 湖州机床厂有限公司 Composite oil cylinder
US20130061959A1 (en) * 2011-09-13 2013-03-14 Kirt N. Stephens Hydraulic valve with an annular filter element secured by a helical spring
CN203963114U (en) * 2014-07-18 2014-11-26 台州市兴乐水暖器材有限公司 Constant temperature valve core
CN106050775A (en) * 2016-06-11 2016-10-26 宁波文泽机电技术开发有限公司 Pilot control valve of improved structure

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