CN109611414B - Pilot-operated type hydraulic lock - Google Patents
Pilot-operated type hydraulic lock Download PDFInfo
- Publication number
- CN109611414B CN109611414B CN201910085490.2A CN201910085490A CN109611414B CN 109611414 B CN109611414 B CN 109611414B CN 201910085490 A CN201910085490 A CN 201910085490A CN 109611414 B CN109611414 B CN 109611414B
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- China
- Prior art keywords
- hole
- valve core
- valve
- fixedly arranged
- sleeve
- 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.)
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Links
- 230000007246 mechanism Effects 0.000 claims description 8
- 238000007789 sealing Methods 0.000 claims description 4
- 230000001174 ascending effect Effects 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 33
- 239000010720 hydraulic oil Substances 0.000 description 12
- 238000000034 method Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
- F15B15/26—Locking mechanisms
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Safety Valves (AREA)
Abstract
The invention discloses a pilot type hydraulic lock which comprises a valve sleeve (1), a plug (2), a valve core (3) and a pilot cone valve core (4), wherein a stepped hole A (5) is formed in the right end part of the plug (2), an internal thread (6) is formed in the inner wall of a large hole of the stepped hole A (5), an external thread (7) is formed in the cylindrical surface of the left end of the valve sleeve (1), a radial hole (8) is formed in the cylindrical surface of the right end of the valve sleeve (1) around the circumferential direction of the cylindrical surface, a guide hole (9), an annular cavity (10) and an oil inlet hole (11) are sequentially formed in the valve sleeve (1) from left to right along the axial direction of the valve sleeve, the annular cavity (10) is communicated with the radial hole (8), and the joint of the oil inlet hole (11) and the annular cavity (10) is a valve seat (12). The beneficial effects of the invention are as follows: compact structure, stable descending and ascending of the weight, sensitive action and simple operation.
Description
Technical Field
The invention relates to the technical field of hydraulic lock structures, in particular to a pilot type hydraulic lock.
Background
In the application of construction machines, agricultural machines and construction machines, it is often necessary to lift and lower heavy objects, such as hoisting mechanisms of cranes, luffing of luffing arms, luffing arms of loaders, hoisting mechanisms of tractors, etc. The weight or the oil cylinder or the piston is locked at a certain position, and the stable descending is realized in the descending process. The usual solution is to use a balancing valve, which, however, is relatively complex in construction and costly to manufacture, often for high flow hydraulic systems. The existing pilot hydraulic lock is complex in structure, hydraulic control is adopted for controlling the opening and closing of the hydraulic lock, and the existing pilot hydraulic lock is insensitive to opening or closing. The pilot cone valve core in the existing pilot hydraulic lock is pushed by a piston rod of an oil cylinder to open the pilot cone valve core, namely the oil cylinder is installed at the vertical position of the hydraulic lock, although the pilot cone valve core can be opened, if the position of the oil cylinder is changed, namely the piston rod is eccentric, the piston rod can not be pressed against the pilot cone valve core at all, but is pressed against the valve core, so that the pilot hydraulic lock can not be opened finally, and a large potential safety hazard exists. In addition, even if the piston rod is not in the same straight line with the pilot cone valve core, the pilot cone valve core is likely to be eccentric, and finally the pilot cone valve core is bent, so that the potential safety hazard is also high.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide the pilot hydraulic lock which has compact structure, ensures stable descending and ascending of a weight, has sensitive action, ensures accurate opening of a pilot cone valve core and is simple to operate.
The aim of the invention is achieved by the following technical scheme: a pilot hydraulic lock comprises a valve sleeve, a plug, a valve core and a pilot cone valve core, wherein a stepped hole A is formed in the right end part of the plug, an internal thread is formed in the inner wall of a large hole of the stepped hole A, an external thread is formed in the cylindrical surface of the left end of the valve sleeve, a radial hole is formed in the cylindrical surface of the right end of the valve sleeve around the cylindrical surface, a guide hole, an annular cavity and an oil inlet hole are sequentially formed in the valve sleeve from left to right along the axial direction of the valve sleeve, the annular cavity is communicated with the radial hole, the joint of the oil inlet hole and the annular cavity is a valve seat, the valve sleeve is fixedly connected to the plug through the external thread and the internal thread of the plug, the left end part of the valve core is slidably mounted in the guide hole, the right end part of the valve core is a conical surface, a spring A is fixedly arranged between the valve core and the plug, one end of the spring A is fixedly arranged in the small hole of the stepped hole A, the other end of the valve core is fixedly arranged on the left end surface of the valve core, the conical surface of the valve core is pressed against the valve seat under the elasticity of the spring A, the stepped hole B is sequentially arranged in the axial direction of the valve core, one end of the stepped hole B is communicated with the oil inlet hole, one end of the large hole of the stepped hole is fixedly arranged on the large hole of the valve seat, the guide cone B is fixedly arranged on the guide cone B, and the other end of the valve core is fixedly arranged on the other end of the valve core, and the other end of the valve core is fixedly arranged on the conical surface B, and one end of the valve seat is fixedly arranged on the end of the valve seat; the hydraulic lock is characterized in that a throttling small hole communicated with a stepped hole B is formed in the cylindrical surface of the valve core, the throttling small hole is formed between a throttling screw and a pilot cone valve core, a stand column is fixedly arranged on the right end face of the pilot cone valve core, the stand column penetrates through the small hole of the stepped hole B, a conical hole is formed in the end face of the stand column, the hydraulic lock further comprises a pilot cone valve core jacking mechanism, the pilot cone valve core jacking mechanism comprises a frame, a guide sleeve, a push rod, a spring and a baffle, the frame is welded on the end face of the valve sleeve, the guide sleeve is fixedly arranged on the frame in a horizontal mode, the push rod is slidably mounted in the guide sleeve, the push rod and the conical hole are coaxially arranged, the left end portion of the push rod extends leftwards, the extending end of the push rod is fixedly provided with a conical head matched with the conical hole, the right end portion of the push rod extends rightwards, the spring is fixedly arranged between the guide sleeve and the baffle, one end of the spring is welded on the right end face of the guide sleeve, and the other end of the spring is welded on the right end face of the baffle.
The left end part of the large hole of the step hole B is provided with a threaded hole, and the throttling screw is in threaded connection with the threaded hole.
The radial holes are uniformly distributed on the cylindrical surface of the valve sleeve.
Sealing rings are arranged on the cylindrical surfaces of the plug and the valve sleeve.
The invention has the following advantages: the invention has compact structure, ensures the stable descending and ascending of the weight, has sensitive action and simple operation.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a front cross-sectional view of FIG. 1;
in the figure, the valve sleeve comprises a valve sleeve body 1, a plug body 2, a valve core 3, a guide cone valve core 4, a stepped hole A5, an internal thread 6, an external thread 7, a radial hole 8, a guide hole 9, an annular cavity 10, an oil inlet 11, a valve seat 12, a conical surface 13, a spring A14, a stepped hole B15, a throttling screw 16, a spring B17, a throttling small hole 18, a column 19, a sealing ring 20, a conical hole 21, a frame 22, a guide sleeve 23, a push rod 24, a spring 25, a baffle 26 and a conical head 27.
Detailed Description
The invention is further described below with reference to the accompanying drawings, the scope of the invention not being limited to the following:
as shown in figures 1-2, the pilot hydraulic lock comprises a valve sleeve 1, a plug 2, a valve core 3 and a pilot cone valve core 4, wherein sealing rings 20 are arranged on cylindrical surfaces of the plug 2 and the valve sleeve 1, a stepped hole A5 is formed in the right end part of the plug 2, an internal thread 6 is formed in the inner wall of a large hole of the stepped hole A5, an external thread 7 is formed in the cylindrical surface of the left end of the valve sleeve 1, a radial hole 8 is formed in the cylindrical surface of the right end of the valve sleeve 1 around the circumferential direction, a guide hole 9, an annular cavity 10 and an oil inlet 11 are sequentially formed in the valve sleeve 1 from left to right along the axial direction, the annular cavity 10 is communicated with the radial hole 8, a valve seat 12 is arranged at the joint of the oil inlet 11 and the annular cavity 10, the valve sleeve 1 is fixedly connected to the plug 2 through the internal thread 6 of the external thread 7, and the left end part of the valve core 3 is slidably mounted in the guide hole 9, the right end of the valve core 3 is a conical surface 13, a spring A14 is fixedly arranged between the valve core 3 and the plug 2, one end of the spring A14 is fixedly arranged in a small hole of the stepped hole A5, the other end of the spring A14 is fixedly arranged on the left end surface of the valve core 3, the conical surface 13 of the valve core 3 is propped against the valve seat 12 under the elasticity of the spring A14, a stepped hole B15 is axially formed in the valve core 3, the stepped hole B15 is communicated with the oil inlet hole 11, one end of a large hole of the stepped hole B15 is fixedly provided with a throttling screw 16, the other end of the large hole of the stepped hole B15 is slidingly provided with a pilot cone valve core 4, a spring B17 is fixedly arranged between the pilot cone valve core 4 and the throttling screw 16, one end of the spring B17 is fixedly arranged on the throttling screw 16, the other end of the spring B17 is fixedly arranged on the left end surface of the pilot cone valve core 4, and the conical surface of the pilot cone valve core 4 is propped against the shoulder of the stepped hole B15 under the elasticity of the spring B17; a throttle small hole 18 communicated with the stepped hole B15 is formed in the cylindrical surface of the valve core 3, and the throttle small hole 18 is positioned between the throttle screw 16 and the pilot cone valve core 4.
The right end face of the pilot cone valve core 4 is fixedly provided with a stand column 19, the stand column 19 penetrates through a small hole of the step hole B15, the left end part of a large hole of the step hole B15 is provided with a threaded hole, and the throttling screw 16 is in threaded connection with the threaded hole. The radial holes 8 are uniformly distributed on the cylindrical surface of the valve sleeve 1. The end face of the upright post 19 is provided with a conical hole 21, the hydraulic lock further comprises a pilot cone valve core jacking mechanism, the pilot cone valve core jacking mechanism comprises a frame 22, a guide sleeve 23, a push rod 24, a spring 25 and a baffle 26, the frame 22 is welded on the end face of the valve sleeve 1, the guide sleeve 23 which is horizontally arranged is fixedly arranged on the frame 22, the push rod 24 is slidably arranged in the guide sleeve 23, the push rod 24 and the conical hole 21 are coaxially arranged, the left end part of the push rod 24 extends leftwards, the extending end is fixedly provided with the baffle 26, the leftmost end part of the push rod 24 is fixedly provided with a conical head 27 matched with the conical hole 21, the right end part of the push rod 24 extends rightwards, the spring 25 is fixedly arranged between the guide sleeve 23 and the baffle 26, one end of the spring 25 is welded on the right end face of the guide sleeve 23, and the other end of the spring 25 is welded on the right end face of the baffle 26.
The working process of the invention is as follows:
connecting the radial hole 8 with an oil pipe, and connecting the other end of the oil pipe to an oil inlet of a lifting oil cylinder;
when a heavy object is to be lifted, hydraulic oil is pumped into the oil inlet hole 11, when the hydraulic oil enters from the oil inlet hole 11 of the valve sleeve 1, the hydraulic oil overcomes the elasticity of the spring A14 to push the valve core 3 leftwards, at the moment, the conical surface of the valve core 3 is separated from the valve seat 12, the radial hole 8 is communicated with the oil inlet hole 11, namely, the hydraulic oil is conducted positively, and the hydraulic oil sequentially enters into a rodless cavity of the lifting oil cylinder through the oil inlet hole 11, the annular cavity 10 and the radial hole 8, so that the heavy object is lifted; when the weight reaches a proper position, the pumping of hydraulic oil into the oil inlet hole 11 is stopped, and under the elasticity of the spring A14, the conical surface of the valve core 3 is propped against the valve seat 12 again, so that the hydraulic oil in the rodless cavity of the lifting oil cylinder is blocked from flowing back into the oil inlet hole 11 through the radial hole 8, and the lifting position of the weight is maintained;
when a heavy object is to be lowered, a worker only needs to push the right end part of the ejector rod 24 to the right, the conical head 27 stretches into the conical hole 21 and pushes the upright post 19 of the pilot cone valve core 4, the spring 25 is compressed at the same time, the pilot cone valve core 4 is further moved leftwards along the big hole of the step hole B15, when the pilot cone valve core 4 moves to the left side of the radial hole 8, hydraulic oil in the rodless cavity of the lifting cylinder flows out of the oil inlet hole 11 sequentially through the radial hole 8, the annular cavity 10, the throttling small hole 18, the big hole of the step hole B15 and the small hole of the step hole B15, and hydraulic oil at the oil inlet hole 11 acts on the right end surface of the valve core 3 due to pressure, and then the valve core 3 is pushed to move leftwards, at the moment, the conical surface 13 is separated from the valve seat 12, and the hydraulic oil of the lifting cylinder flows back to the small hole of the step hole B15 sequentially through the radial hole 8, the annular cavity 10, the throttling small hole 18 and the big hole of the step hole B15, and the oil inlet hole 11, so that is stably lowering of the heavy object is stably is realized is stably is lowered; because the ejector rod 24 and the conical hole 21 are always in a coaxial state, and the guide sleeve 23 is also fixed, the ejector rod 24 cannot be misplaced with the pilot cone valve core 4 after the reciprocating work, so that the pilot cone valve core 4 can be opened each time, compared with the traditional piston rod opening mode adopting an oil cylinder, the piston rod opening mode adopting the oil cylinder does not need to frequently adjust the position of the oil cylinder, and the labor intensity of workers is reduced;
when the heavy object is required to stop descending in the descending process, a worker immediately releases the ejector rod 24, the ejector rod 24 moves rightwards along the guide sleeve 23 under the action of the restoring force of the spring 25, and the pilot cone valve core 4 moves rightwards under the action of the spring B17 until the conical surface of the pilot cone valve core 4 abuts against the shoulder of the stepped hole B15; the oil return of the lifting oil cylinder sequentially enters the large hole of the stepped hole B15 through the radial hole 8, the annular cavity 10 and the throttling small hole 18, the pressure in the stepped hole B15 is increased by hydraulic oil, and then the conical surface of the valve core 3 is abutted against the valve seat 12 under the action of the spring A14 and the action of the hydraulic oil, so that the oil return of the lifting oil cylinder is stopped, and the heavy object stops descending. Therefore, the pilot hydraulic lock replaces the original hydraulic control valve to be opened and closed, but the pilot hydraulic lock is mechanically started, so that the action is more sensitive. Meanwhile, the weight is ensured to be more stable in the lifting or descending process.
Claims (1)
1. A pilot operated hydraulic lock, characterized by: the valve comprises a valve sleeve (1), a plug (2), a valve core (3) and a pilot cone valve core (4), wherein a stepped hole A (5) is formed in the right end part of the plug (2), an internal thread (6) is formed in the inner wall of a large hole of the stepped hole A (5), an external thread (7) is arranged on the cylindrical surface at the left end of the valve sleeve (1), a radial hole (8) is formed in the cylindrical surface at the right end of the valve sleeve (1) around the circumferential direction of the cylindrical surface, a guide hole (9), an annular cavity (10) and an oil inlet hole (11) are sequentially formed in the valve sleeve (1) from left to right along the axial direction of the valve sleeve, the annular cavity (10) is communicated with the radial hole (8), a valve seat (12) is arranged at the joint part of the oil inlet hole (11) and the annular cavity (10), the valve sleeve (1) is fixedly connected with the internal thread (6) of the plug (2) through the external thread (7), the left end part of the valve core (3) is slidably arranged in the guide hole (9), the right end part of the valve core (3) is a conical surface (13), a small hole (14) is fixedly arranged between the valve core (3) and the valve core (2) and the valve core (14) and the other end face (14) is fixedly arranged in the end face of the valve core (5), the conical surface (13) of the valve core (3) is propped against the valve seat (12) under the elasticity of the spring A (14), a stepped hole B (15) is formed in the valve core (3) along the axial direction of the valve core, the stepped hole B (15) is communicated with the oil inlet hole (11), a throttling screw (16) is fixedly arranged at one end of the large hole of the stepped hole B (15), a pilot cone valve core (4) is slidably arranged at the other end of the large hole of the stepped hole B (15), a spring B (17) is fixedly arranged between the pilot cone valve core (4) and the throttling screw (16), one end of the spring B (17) is fixedly arranged on the throttling screw (16), the other end of the spring B (17) is fixedly arranged on the left end face of the pilot cone valve core (4), and the conical surface of the pilot cone valve core (4) is propped against the stepped hole B (15) under the elasticity of the spring B (17); the hydraulic lock comprises a cylinder surface of a valve core (3) and is characterized in that a throttle small hole (18) communicated with a stepped hole B (15) is formed in the cylinder surface of the valve core (3), the throttle small hole (18) is positioned between a throttle screw (16) and a pilot cone valve core (4), a stand column (19) is fixedly arranged on the right end surface of the pilot cone valve core (4), the stand column (19) penetrates through the small hole of the stepped hole B (15), a conical hole (21) is formed in the end surface of the stand column (19), the hydraulic lock further comprises a pilot cone valve core jacking mechanism, the pilot cone valve core jacking mechanism comprises a frame (22), a guide sleeve (23), a push rod (24), a spring (25) and a baffle plate (26), the frame (22) is welded on the end surface of the valve sleeve (1), the guide sleeve (23) which is horizontally arranged is fixedly arranged on the frame (22), a push rod (24) is slidably arranged on the guide sleeve (23), the push rod (24) and the conical hole (21) are coaxially arranged, the left end part of the push rod (24) extends leftwards, the extending end part of the push rod (24) is fixedly provided with a baffle plate (26), the leftwards end part of the push rod (24) is fixedly arranged on the end surface of the conical hole (21) and the end surface which is fixedly arranged on the end surface of the guide sleeve (25) and is fixedly arranged on the end surface of the guide sleeve (25) which is fixedly arranged on the right end surface of the spring (25), the other end of the spring (25) is welded on the right end face of the baffle (26);
the left end part of the large hole of the step hole B (15) is provided with a threaded hole, and the throttling screw (16) is in threaded connection with the threaded hole;
the radial holes (8) are uniformly distributed on the cylindrical surface of the valve sleeve (1);
sealing rings (20) are arranged on the cylindrical surfaces of the plug (2) and the valve sleeve (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910085490.2A CN109611414B (en) | 2019-01-29 | 2019-01-29 | Pilot-operated type hydraulic lock |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910085490.2A CN109611414B (en) | 2019-01-29 | 2019-01-29 | Pilot-operated type hydraulic lock |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109611414A CN109611414A (en) | 2019-04-12 |
| CN109611414B true CN109611414B (en) | 2024-03-12 |
Family
ID=66018674
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910085490.2A Active CN109611414B (en) | 2019-01-29 | 2019-01-29 | Pilot-operated type hydraulic lock |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109611414B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3723673A1 (en) * | 1987-07-17 | 1989-01-26 | Wessel Hydraulik | Externally controlled non-return valve |
| CN103899596A (en) * | 2014-03-31 | 2014-07-02 | 雷永志 | Hydraulic lock with pilot one-way valve |
| CN107084277A (en) * | 2017-06-30 | 2017-08-22 | 江苏瑞朗博机械设备有限公司 | The buffering type pilot automatic valve triggered based on strut buckling |
| CN209458221U (en) * | 2019-01-29 | 2019-10-01 | 青神格林维尔流体动力控制技术有限公司 | A kind of pilot-operated hydraulic lock |
-
2019
- 2019-01-29 CN CN201910085490.2A patent/CN109611414B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3723673A1 (en) * | 1987-07-17 | 1989-01-26 | Wessel Hydraulik | Externally controlled non-return valve |
| CN103899596A (en) * | 2014-03-31 | 2014-07-02 | 雷永志 | Hydraulic lock with pilot one-way valve |
| CN107084277A (en) * | 2017-06-30 | 2017-08-22 | 江苏瑞朗博机械设备有限公司 | The buffering type pilot automatic valve triggered based on strut buckling |
| CN209458221U (en) * | 2019-01-29 | 2019-10-01 | 青神格林维尔流体动力控制技术有限公司 | A kind of pilot-operated hydraulic lock |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109611414A (en) | 2019-04-12 |
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