Pilot quick response structure of balance valve

Abstract

The invention provides a quick pilot response structure of a balance valve, belongs to the technical field of balance valves, and solves the problem of low response speed in the prior art. The variable damping valve comprises a main valve body and a pilot valve body, a pilot cavity is formed in the main valve body, a first step cavity is formed in the pilot valve body, a variable damping valve element is movably arranged in the first step cavity, an annular conical face is arranged on the variable damping valve element, a throttling groove is formed in the annular conical face, and the variable damping valve element is connected with a reset mechanism. The small-diameter end of the first step cavity is connected with a liquid inlet channel, the large-diameter end of the first step cavity is communicated with the pilot cavity through a hole channel, and a first damper is arranged in the variable damping valve element. After the pressure of the liquid inlet channel is larger than the pressure of the pilot cavity by a certain value, oil pushes the variable damping valve element to move, the oil enters the large-diameter end of the first step cavity through the throttling groove and then flows into the pilot cavity, the rising speed of the pressure of the pilot cavity in the opening stage of the balance valve can be increased, and the response speed of the balance valve is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of balancing valves, and in particular to a balancing valve pilot quick response structure. Background Art

[0002] Pilot-operated balancing valves have the advantages of high rated working pressure, reliable closing, controllable flow, and low energy consumption. They are widely used in situations where working parts move vertically, such as excavators, lifting machinery, missile launchers, and other fields.

[0003] In order to reduce overshoot and oscillation during the operation of the hydraulic system where the pilot balancing valve is located, and to improve the stability of the hydraulic system where the pilot balancing valve is located, a fixed damping is usually provided in the pilot oil circuit of the pilot balancing valve. When the system exceeds the load mutation condition, it is necessary to control the pilot pressure to rise rapidly to open the balancing valve. At this time, the control piston controlled by the pilot pressure needs to move quickly to respond. However, in the existing structure, a fixed damping with a large damping value is provided in the pilot oil circuit for throttling. The pilot chamber pressure of the pilot balancing valve rises slowly during the opening stage, resulting in a long opening response time of the balancing valve. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a balancing valve pilot rapid response structure, in which the oil first passes through the first damping and enters the pilot chamber to push the control piston to move. After the pressure in the liquid inlet channel is greater than a certain value of the pilot chamber pressure, the oil pushes the variable damping valve core to move. The oil enters the end with a larger diameter of the first step chamber through the throttling groove, and then flows into the pilot chamber, thereby realizing the variable damping adjustment effect, which can accelerate the rising speed of the pilot chamber pressure in the opening stage of the balancing valve, accelerate the response speed when the balancing valve is opened, and improve the rapidity of the balancing valve.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A balancing valve pilot quick response structure comprises a main valve body and a pilot valve body connected to the main valve body, wherein a pilot chamber is arranged in the main valve body, a control piston is movably sealed in the pilot chamber, a first step chamber is arranged in the pilot valve body, a variable damping valve core is movably arranged in the first step chamber, an annular conical surface is arranged on the outer wall of the variable damping valve core, a throttling groove is provided on the annular conical surface, the variable damping valve core is connected to a reset mechanism which keeps the annular conical surface abutting against the step of the first step chamber, an end of the first step chamber with a smaller diameter is connected to a liquid inlet channel, an end of the first step chamber with a larger diameter is connected to the pilot chamber through a channel, a first damping is arranged in the variable damping valve core, one end of the first damping is connected to the liquid inlet channel, a first connecting hole is provided on the variable damping valve core, and the first connecting hole connects the other end of the first damping with the end of the first step chamber with a larger diameter.

[0007] Preferably, the reset mechanism comprises a first reset spring abutting against an end of the variable damping valve core.

[0008] Preferably, the reset mechanism further comprises a stud threadedly extending into the pilot valve body and abutting against the first reset spring.

[0009] Preferably, a nut is threadedly provided on the stud, and a movable sleeve on the stud is provided with a sealing gasket located between the nut and the pilot valve body.

[0010] Preferably, one end surface of the variable damping valve core is threadedly provided with a plug.

[0011] Preferably, the pilot valve body is provided with a first installation cavity connected to the end with a larger diameter of the first step cavity and the pilot cavity, the first installation cavity is provided with a one-way valve assembly allowing oil to flow from the pilot cavity to the first installation cavity, a push rod for opening the one-way valve assembly is connected to the control piston, the pilot valve body is provided with a second installation cavity connected to the first installation cavity and the pilot cavity, and a second damper is provided at the connection between the second installation cavity and the first installation cavity.

[0012] Preferably, the one-way valve assembly includes a valve sleeve installed in the first installation cavity, the valve sleeve is provided with a second step cavity connected with the pilot cavity along the axial direction of the push rod, a sealing ball is movably provided at the end with a larger diameter of the second step cavity, a second return spring for abutting the sealing ball against the step of the second step cavity is provided in the valve sleeve, and a second connecting hole connecting the second step cavity and the first installation cavity is provided on the valve sleeve.

[0013] Preferably, the second installation cavity is communicated with the cavity where the reset mechanism is located.

[0014] Preferably, an opening communicating with the outer wall of the pilot valve body is formed in the second installation cavity, and a sealing plug is threadedly and sealedly connected to the opening.

[0015] Preferably, one end of the control piston away from the pilot valve body is connected to a control rod, and a spring group is sleeved on the control rod.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0017] The oil first passes through the first damping and enters the pilot chamber to push the control piston to move. After the pressure in the liquid inlet channel is greater than a certain value of the pilot chamber pressure, the oil pushes the variable damping valve core to move. The oil enters the end with a larger diameter of the first step chamber through the throttling groove, and then flows into the pilot chamber, thereby realizing the adjustment effect of variable damping, which can speed up the rising speed of the pilot chamber pressure in the opening stage of the balancing valve, speed up the response speed when the balancing valve is opened, and improve the rapidity of the balancing valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A schematic cross-sectional structure diagram provided for an embodiment of the present invention;

[0020] Figure 2 A schematic diagram of a push rod detaching from a blocking ball provided in an embodiment of the present invention.

[0021] Figure markings: 1-main valve body; 2-pilot chamber; 3-control piston; 4-second installation chamber; 5-second damping; 6-sealing plug; 7-stud; 8-nut; 9-first return spring; 10-pilot valve body; 11-plug; 12-first connecting hole; 13-variable damping valve core; 14-annular conical surface; 15-first damping; 16-throttling groove; 17-first step chamber; 18-first installation chamber; 19-valve sleeve; 20-second return spring; 21-sealing ball; 22-second connecting hole; 23-second step chamber; 24-push rod; 25-liquid inlet channel; 26-spring group; 27-sealing pad; 28-control rod. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] Combine the following Figure 1 and Figure 2 The present invention is described in detail.

[0026] Example

[0027] A balancing valve pilot quick response structure comprises a main valve body 1 and a pilot valve body 10 connected to the main valve body 1, wherein a pilot chamber 2 is arranged in the main valve body 1, a control piston 3 is movably sealed in the pilot chamber 2, a first step chamber 17 is arranged in the pilot valve body 10, a variable damping valve core 13 is movably arranged in the first step chamber 17, an annular conical surface 14 is arranged on the outer wall of the variable damping valve core 13, a throttling groove 16 is opened on the annular conical surface 14, and the variable damping valve core 13 is connected to a conical surface 14. 14 is a reset mechanism that keeps contact with the step of the first step chamber 17. The end of the first step chamber 17 with a smaller diameter is connected to the liquid inlet channel 25. The end of the first step chamber 17 with a larger diameter is connected to the pilot chamber 2 through a hole. The variable damping valve core 13 is provided with a first damper 15. One end of the first damper 15 is connected to the liquid inlet channel 25. The variable damping valve core 13 is provided with a first connecting hole 12. The first connecting hole 12 connects the other end of the first damper 15 with the end with a larger diameter of the first step chamber 17. When the annular conical surface 14 contacts with the first step chamber 17, the annular conical surface 14 and the step of the first step chamber 17 form a sealing structure to prevent oil from flowing therefrom.

[0028] The oil enters the lower end of the first step chamber 17 (i.e., the end with a smaller diameter of the first step chamber 17) from the inlet channel 25, and the oil first passes through the first damping 15 with a fixed damping value, and then flows into the upper end of the first step chamber 17 (i.e., the end with a larger diameter of the first step chamber 17) from the first connecting hole 12, and the oil enters the pilot chamber 2 through the hole to push the control piston 3 to move to the right; in the opening stage of the balancing valve, the pressure in the inlet channel 25 rises rapidly, and after the oil pressure in the inlet channel 25 exceeds a certain value of the oil pressure in the pilot chamber 2, the variable damping valve The pressure on the lower end of the core 13 is greater than the combined force of the upper end pressure and the reset force of the reset mechanism, thereby pushing the variable damping valve core 13 to move upward, and the throttling groove 16 on the side of the variable damping valve core 13 also moves upward to offset the step of the first step chamber 17. The throttling groove 16 and the step of the first step chamber 17 form an oil outlet gap, which increases the oil flow channel outside the first damping 15, thereby reducing the damping value at the variable damping valve core 13, further increasing the oil flow rate flowing into the pilot chamber 2, accelerating the oil pressure rising speed of the pilot chamber 2, and increasing the opening speed of the balancing valve.

[0029] When the oil pressure in the liquid inlet channel 25 does not exceed a certain value of the oil pressure in the pilot chamber 2, the variable damping valve core 13 remains closed under the action of the reset mechanism, and the oil in the liquid inlet channel 25 only flows into the pilot chamber 2 through the first damping 15, thereby ensuring the stability of the balancing valve when the opening reaches the pilot set value.

[0030] The reset mechanism includes a first reset spring 9 abutting against the end of the variable damping valve core 13. The first reset spring 9 is a compression spring arranged at the upper end of the variable damping valve core 13 and abutting against the variable damping valve core 13, thereby realizing automatic reset of the variable damping valve core 13. The first reset spring 9 can also be replaced by a tension spring connected to the lower end of the variable damping valve core 13, but in order to facilitate the installation of the first reset spring 9, a compression spring is preferably used.

[0031] The reset mechanism also includes a stud 7 threadedly extending into the pilot valve body 10 and abutting against the first reset spring 9. The stud 7 can adjust the preload force of the first reset spring 9 so as to select different reset forces for different working conditions, and the first reset spring 9 can be easily disassembled after the stud 7 is removed.

[0032] The stud 7 is threaded with a nut 8, and the stud 7 is sleeved with a sealing gasket 27 between the nut 8 and the pilot valve body 10. The sealing gasket 27 seals the gap between the stud 7 and the pilot valve body 10 under the compression of the nut 8 to prevent leakage of oil.

[0033] like Figure 1As shown, a plug 11 is threadedly provided on one end face of the variable damping valve core 13. The plug 11 is provided at one end of the variable damping valve core 13 close to the first return spring 9. The variable damping valve core 13 is a hollow structure. After removing the plug 11, the first damping 15 can be conveniently disassembled and assembled; wherein the first damping 15 is threadedly connected to the variable damping valve core 13.

[0034] The pilot valve body 10 is provided with a first installation cavity 18 which is connected with the end with a larger diameter of the first step cavity 17 and the pilot cavity 2. The first installation cavity 18 is provided with a one-way valve assembly which allows oil to flow from the pilot cavity 2 to the first installation cavity 18. A push rod 24 for opening the one-way valve assembly is connected to the control piston 3. The pilot valve body 10 is provided with a second installation cavity 4 which is connected with the first installation cavity 18 and the pilot cavity 2. A second damper 5 is provided at the connection between the second installation cavity 4 and the first installation cavity 18.

[0035] Under the action of the push rod 24, the one-way valve assembly remains in an open state (i.e., the oil flows freely between the pilot chamber 2 and the first installation chamber 18), and the oil enters the pilot chamber 2 through the one-way valve assembly and the second damper 5; after the oil pushes the control piston 3 to move to the right, the push rod 24 is separated from the one-way valve assembly, and the one-way valve assembly is closed at this time, and the oil can only enter the pilot chamber 2 from the second damper 5, so that the opening of the balance valve is further increased. At this time, the second damper 5 can maintain the stable operation of the balance valve under the condition of large oil flow. When the balance valve is opened and closed, the pressure of the liquid inlet channel 25 decreases, and the oil in the pilot chamber 2 pushes the one-way valve assembly to open, and the oil finally flows out from the first damper 15.

[0036] The one-way valve assembly includes a valve sleeve 19 installed in the first installation cavity 18. The valve sleeve 19 is provided with a second step cavity 23 connected with the pilot cavity 2 along the axial direction of the push rod 24. A sealing ball 21 is movably provided at the end with a larger diameter of the second step cavity 23. A second return spring 20 for abutting the sealing ball 21 against the step of the second step cavity 23 is provided in the valve sleeve 19. A second connecting hole 22 connecting the second step cavity 23 and the first installation cavity 18 is provided on the valve sleeve 19.

[0037] The sealing ball 21 can move in the valve sleeve 19, and a second return spring 20 is provided to abut the sealing ball 21 against the step of the second step chamber 23, thereby realizing the closing of the one-way valve assembly; the push rod 24 moves along the axial direction of the valve sleeve 19 and extends into the second step chamber 23, thereby abutting the sealing ball 21 and moving in the direction of the second return spring 20, and the oil enters the second step chamber 23 from the second connecting hole 22 and flows into the pilot chamber 2 from the gap between the push rod 24 and the valve sleeve 19.

[0038] The second installation cavity 4 is communicated with the cavity where the reset mechanism is located. The oil in the second installation cavity 4 can enter the cavity where the reset mechanism is located to lubricate related structures.

[0039] The second installation cavity 4 is provided with an opening connected to the outer wall of the pilot valve body 10, and the opening is threadedly sealed with a sealing plug 6. The sealing plug 6 can facilitate the subsequent disassembly and assembly of the second damper 5, wherein the second damper 5 is threadedly connected to the pilot valve body 10.

[0040] The end of the control piston 3 away from the pilot valve body 10 is connected to a control rod 28, and a spring group 26 is sleeved on the control rod 28. After the control piston 3 moves, the control rod 28 drives the balance valve to open. The spring group 26 is composed of a large spring and a small spring to increase the stiffness of the spring group 26, so that the control piston 3 can be normally reset to the left.

[0041] By adopting the above technical solution, it can be used to overcome the working condition where the pilot needs to open quickly under sudden load changes. When the pilot pressure rises quickly, the pressure in the pilot chamber 2 connected to the control piston 3 accelerates to rise, so that the control piston 3 controlled by the pilot pressure moves quickly to respond, thereby accelerating the opening of the balancing valve and the response speed when the pilot needs to open quickly under sudden working conditions, thereby improving the rapidity of the balancing valve.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A balancing valve pilot quick response structure, comprising a main valve body (1) and a pilot valve body (10) connected to the main valve body (1), wherein the main valve body (1) is provided with a pilot chamber (2), and a control piston (3) is movably sealed in the pilot chamber (2), characterized in that: The pilot valve body (10) is provided with a first step cavity (17), a variable damping valve core (13) is movably provided in the first step cavity (17), an annular conical surface (14) is provided on the outer wall of the variable damping valve core (13), a throttling groove (16) is provided on the annular conical surface (14), the variable damping valve core (13) is connected to a reset mechanism that keeps the annular conical surface (14) in contact with the step of the first step cavity (17), and the first step cavity (17) has a relatively large diameter. The smaller end is connected to a liquid inlet channel (25), the larger end of the first step chamber (17) is connected to the pilot chamber (2) through a hole, a first damper (15) is arranged in the variable damping valve core (13), one end of the first damper (15) is connected to the liquid inlet channel (25), and a first communicating hole (12) is provided on the variable damping valve core (13), and the first communicating hole (12) connects the other end of the first damper (15) with the larger end of the first step chamber (17).

2. A balancing valve pilot quick response structure according to claim 1, characterized in that: The reset mechanism comprises a first reset spring (9) abutting against the end of the variable damping valve core (13).

3. A balancing valve pilot quick response structure according to claim 2, characterized in that: The reset mechanism further comprises a stud (7) which is threadedly inserted into the pilot valve body (10) and abuts against the first reset spring (9).

4. A balancing valve pilot quick response structure according to claim 3, characterized in that: The stud (7) is threadedly provided with a nut (8), and a seal gasket (27) is movably sleeved on the stud (7) and located between the nut (8) and the pilot valve body (10).

5. A balancing valve pilot quick response structure according to claim 1, characterized in that: One end surface of the variable damping valve core (13) is threadedly provided with a plug (11).

6. A balancing valve pilot quick response structure according to claim 1, characterized in that: The pilot valve body (10) is provided with a first installation cavity (18) which is connected to the end with a larger diameter of the first step cavity (17) and the pilot cavity (2); the first installation cavity (18) is provided with a one-way valve assembly which allows oil to flow from the pilot cavity (2) to the first installation cavity (18); a push rod (24) for opening the one-way valve assembly is connected to the control piston (3); the pilot valve body (10) is provided with a second installation cavity (4) which is connected to the first installation cavity (18) and the pilot cavity (2); and a second damper (5) is provided at the connection between the second installation cavity (4) and the first installation cavity (18).

7. A balancing valve pilot rapid response structure according to claim 6, characterized in that: The one-way valve assembly comprises a valve sleeve (19) installed in a first installation cavity (18); the valve sleeve (19) is provided with a second step cavity (23) connected to the pilot cavity (2) along the axial direction of the push rod (24); a blocking ball (21) is movably provided at the end with a larger diameter of the second step cavity (23); a second return spring (20) is provided in the valve sleeve (19) for abutting the blocking ball (21) against the step of the second step cavity (23); and a second connecting hole (22) connecting the second step cavity (23) and the first installation cavity (18) is provided on the valve sleeve (19).

8. A balancing valve pilot quick response structure according to claim 6, characterized in that: The second installation cavity (4) is in communication with the cavity where the reset mechanism is located.

9. A balancing valve pilot rapid response structure according to claim 6, characterized in that: The second installation cavity (4) is provided with an opening which is in communication with the outer wall of the pilot valve body (10), and a sealing plug (6) is threadedly and sealingly connected to the opening.

10. A balancing valve pilot rapid response structure according to claim 1, characterized in that: One end of the control piston (3) away from the pilot valve body (10) is connected to a control rod (28), and a spring group (26) is sleeved on the control rod (28).

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