A constant flow pressure reducing valve

Abstract

This invention discloses a constant flow pressure reducing valve, relating to the field of hydraulic valve technology. It includes a valve seat with an oil outlet, an oil inlet, and a drain port arranged sequentially from right to left. An elastic pressure regulating component is located at the left end of the valve seat, and a spool valve core is abutted at the right end of the elastic pressure regulating component. An axially movable elastic flow control valve core is located at the right end of the spool valve core. A drain channel communicating with the inner cavity of the valve seat is opened at the left end of the spool valve core, and the drain channel is connected to the drain port. The valve core slides within the valve seat, allowing oil to flow out from the drain port to relieve pressure. An oil inlet channel communicating with the oil inlet is located at the right end of the spool valve core, and a throttling channel communicating with both the oil inlet and outlet is provided on the elastic flow control valve core. The movement of the elastic flow control valve core within the valve seat maintains a constant pressure difference between the throttling channel and the oil inlet channel, thereby achieving a constant output flow rate. This constant flow pressure reducing valve achieves pressure reduction in the oil circuit and a constant output flow rate, facilitating processing and disassembly, and simplifying the hydraulic circuit.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of hydraulic valve, more particularly, to a constant flow pressure reducing valve. BACKGROUND

[0002] The hydraulic threaded plug-in pressure reducing valve is one of the hydraulic system oil pressure control elements, which has become a necessary hydraulic element for fluid control due to its easy installation, small size and convenient pressure adjustment. In the prior art, if the hydraulic circuit needs to output with constant flow and realize the function of pressure reduction, the hydraulic threaded plug-in pressure reducing valve and the constant flow valve must be used simultaneously to realize the constant flow pressure reduction effect. It is found in use that, due to the simultaneous use of the hydraulic threaded plug-in pressure reducing valve and the constant flow valve, the connection structure is relatively complex, the required installation space is relatively large, and a relatively complex hydraulic oil circuit needs to be designed, which is inconvenient for installation, adjustment, disassembly and maintenance. SUMMARY

[0003] In view of the defects of the prior art, the purpose of the present application is to provide a constant flow pressure reducing valve, which aims to solve the problems of large installation space, complex structure, complex hydraulic oil circuit and inconvenient installation and adjustment caused by the simultaneous use of the pressure reducing valve and the constant flow valve.

[0004] To achieve the above-mentioned purpose, the present application provides a constant flow pressure reducing valve, which comprises a valve seat with a hollow inside, wherein an oil outlet, an oil inlet and an oil discharge port are sequentially arranged on the valve seat from right to left; an elastic pressure regulating assembly is arranged at the left end of the valve seat, the right end of the elastic pressure regulating assembly abuts against a spool core, the spool core is axially movable in the valve seat, and an axially movable elastic flow valve core is arranged at the right end of the spool core; an oil discharge channel is formed in the left end of the spool core and communicates with the inner cavity of the valve seat, the oil discharge channel communicates with the oil discharge port, and the spool core is slid in the valve seat to make the oil flow out of the oil discharge port to realize pressure relief; an oil inlet channel is arranged at the right end of the spool core and communicates with the oil inlet, and a throttling channel is arranged on the elastic flow valve core and communicates with the oil inlet channel and the oil outlet; the elastic flow valve core moves in the valve seat to keep the pressure difference between the throttling channel and the oil inlet channel constant, thereby realizing constant output flow.

[0005] Further, the spool core is provided with an oil discharge cavity with an open left end along the axial direction, the left end of the oil discharge cavity is provided with an inlet hole along the radial direction and communicating with the inner cavity of the valve seat, an oil discharge groove is arranged on the outer wall of the spool core, the right end of the oil discharge cavity is provided with an outlet hole communicating with the oil discharge groove, and the oil discharge cavity, the inlet hole, the oil discharge groove and the outlet hole cooperate to form an oil discharge channel, and the oil discharge channel communicates with the oil discharge port.

[0006] Further, the spool is provided with an oil inlet cavity with an open right end in the axial direction, and an oil inlet groove is arranged on the outer wall of the spool, and the outer wall of the oil inlet cavity is uniformly provided with oil inlet holes in the circumferential direction, which are communicated with the oil inlet groove, and the oil inlet cavity, the oil inlet holes and the oil inlet groove cooperatively form an oil inlet channel, which is communicated with the oil inlet port.

[0007] Further, the valve seat is provided with a flow valve sleeve with an open left end and a hollow interior, and the elastic flow valve core is axially movable in the flow valve sleeve, and the outer wall of the flow valve sleeve is provided with oil outlet holes in the circumferential direction, and the elastic flow valve core comprises a valve core, the left end of the valve core is provided with an oil delivery hole, the valve core is provided with a valve cavity communicated with the oil delivery hole, the valve cavity is provided with a spring, one end of the spring abuts against the inner wall of the valve core, and the other end of the spring abuts against the inner wall of the flow valve sleeve, the oil delivery hole, the valve cavity and the oil outlet hole cooperatively form a throttling channel, and the movement of the valve core in the flow valve sleeve keeps the pressure difference before and after the oil delivery hole constant, thereby realizing constant output flow.

[0008] Further, the flow valve sleeve and the valve seat are connected by threads, and a dismounting groove is arranged on the right end face of the flow valve sleeve.

[0009] Further, the left end of the spool is provided with a limiting boss, and the inner wall of the valve seat is provided with a limiting step corresponding to the limiting boss.

[0010] Further, the left end of the valve seat is provided with a screw sleeve, the elastic pressure regulating assembly comprises a pressure regulating rod screwed with the screw sleeve, the left end of the pressure regulating rod abutting against the end face of the screw sleeve is provided with a locking nut, the right end of the pressure regulating rod is provided with a pressure regulating spring, the other end of the pressure regulating spring is provided with a spring seat, and the spring seat is embedded with a steel ball for limiting the installation of the spool.

[0011] Further, the pressure regulating rod is provided with an annular boss, the annular boss is sleeved in the valve seat, a sealing groove is arranged on the outer wall of the annular boss, and a retainer ring and a sealing ring are arranged in the sealing groove.

[0012] Further, the valve seat comprises a valve seat body, the right end of the valve seat body is detachably connected with a valve sleeve, the spool and the elastic flow valve core are located in the valve sleeve, and the oil outlet port, the oil inlet port and the oil discharge port are sequentially arranged on the valve sleeve from right to left.

[0013] Further, a step hole is arranged on the valve sleeve, the flow valve sleeve and the step hole cooperatively form the oil outlet port, and a tool withdrawal groove is further arranged on the inner wall of the valve sleeve, which is located between the spool and the elastic flow valve core.

[0014] Overall, compared with the prior art, the above technical solutions conceived by the present application have the following beneficial effects:

[0015] 1. The present application is provided with a slide valve core and an elastic flow valve core in the valve seat, and the pressure relief is realized by the communication of the oil discharge channel and the oil discharge port arranged in the slide valve core, and at the same time, the throttle channel is arranged in the elastic flow valve core to ensure the constant flow at the oil outlet, so that the functions of the pressure reducing valve and the constant flow valve are integrated, the constant flow pressure reduction is realized, and the application space can be smaller, and the structure and oil circuit design for simultaneously using the pressure reducing valve and the constant flow valve are simplified.

[0016] 2. At the same time, the elastic pressure regulating assembly is arranged, the elastic pressure regulating assembly comprises a pressure regulating rod, the pressure regulating rod and the screw sleeve are threadedly connected, the length of the pressure regulating rod in the valve seat can be adjusted according to the actual application requirement, so that the elastic force of the elastic pressure regulating assembly is adjusted, and then the required pressure reducing pressure of the system is adjusted.

[0017] 3. In addition, the valve seat is divided into a valve seat body and a valve sleeve, so that the machining is facilitated and the disassembly and maintenance are facilitated. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a structure sectional view of the constant flow pressure reducing valve provided by the present application;

[0019] Figure 2 is Figure 1 a local enlarged view of A in

[0020] Figure 3 is a structure schematic view of the constant flow pressure reducing valve provided by the present application;

[0021] Figure 4 is a structure sectional view of the constant flow pressure reducing valve provided by the present application from another perspective;

[0022] Figure 5 is a hydraulic principle diagram of the constant flow pressure reducing valve provided by the present application.

[0023] The structures corresponding to the numbers in the diagram are as follows: 1-valve seat, 11-valve seat body, 12-valve sleeve, 121-stepped opening, 122-relief groove, 2-elastic pressure regulating component, 21-pressure regulating rod, 211-annular boss, 212-sealing groove, 213-retaining ring, 214-sealing ring, 22-pressure regulating spring, 23-spring seat, 24-steel ball, 3-slide valve core, 31-oil drain channel, 311-oil drain chamber, 312-liquid inlet, 313-... - Oil drain groove, 314- Liquid outlet hole, 32- Oil inlet channel, 321- Oil inlet chamber, 322- Oil inlet hole, 323- Oil inlet groove, 33- Limiting boss, 4- Elastic flow valve core, 41- Throttling channel, 42- Valve core, 421- Oil delivery hole, 422- Valve chamber, 43- Spring, 5- Flow valve sleeve, 51- Oil outlet hole, 52- Disassembly groove, 6- Screw sleeve, 7- Locking nut, a1- Oil outlet, a2- Oil inlet, a3- Oil drain port. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] See Figure 1 Only Figure 4 The constant flow pressure reducing valve of the present invention includes a hollow valve seat 1, on which an oil outlet a1, an oil inlet a2, and an oil drain a3 are arranged sequentially from right to left; an elastic pressure regulating component 2 is provided at the left end of the valve seat 1, and a slide valve core 3 is abutted at the right end of the elastic pressure regulating component 2. The slide valve core 3 is axially movable within the valve seat 1, and when the slide valve core 3 moves axially, it can compress the elastic pressure regulating component 2; an axially movable elastic flow valve core 4 is provided at the right end of the slide valve core 3; in order to realize the discharge of oil from the pressure regulating spring cavity inside the valve seat and reduce the pressure reduction pressure Due to the influence of force, the left end of the spool valve core 3 is provided with an oil drain channel 31 that communicates with the inner cavity of the valve seat 1, and the oil drain channel 31 is connected to the oil drain port a3; in order to ensure that the flow rate at the oil outlet a1 is constant, the right end of the spool valve core 3 is provided with an oil inlet channel 32 that communicates with the oil inlet port a2, and the elastic flow valve core 4 is provided with a throttling channel 41 that communicates with the oil inlet channel 32 and the oil outlet a1; the elastic flow valve core 4 moves in the valve seat 1 to keep the pressure difference between the throttling channel 41 and the oil inlet channel 32 constant, thereby achieving a constant output flow rate.

[0026] To achieve pressure reduction, specifically, a portion of the high-pressure oil leaks from the inlet a2 through the gap between the spool valve core 3 and the valve seat 1 into the cavity at the left end of the valve seat 1, and then exits through the drain port a3. The other portion of the high-pressure oil enters the inlet channel 32 from the inlet a2 and flows to the right end of the spool valve core 3. The pressure generated by this flow acts on the right end face of the spool valve core 3. When the pressure generated by the high-pressure oil is equal to or greater than the elastic force generated by the elastic pressure regulating component 2, the spool valve core 3 moves to the left, adjusting the flow area of ​​the oil between the spool valve core 3 and the inlet a2, thus achieving pressure reduction. Specifically, the spool valve core 3 has an oil drain chamber 311 with an opening at the left end along the axial direction. The left end of the oil drain chamber 311 has an inlet hole 312 that communicates with the inner cavity of the valve seat 1 along the radial direction. The outer wall of the spool valve core 3 has an oil drain groove 313. The right end of the oil drain chamber 311 has an outlet hole 314 that communicates with the oil drain groove 313. The oil drain chamber 311, the inlet hole 312, the oil drain groove 313 and the outlet hole 314 cooperate to form an oil drain channel 31. The oil drain channel 31 communicates with the oil drain port a3. When the valve core 3 slides in the valve seat 1, the oil can flow out from the oil drain port a3.

[0027] To facilitate the limiting of the slide valve core 3 during installation, a limiting boss 33 is provided on the left end of the slide valve core 3. At the same time, a limiting step corresponding to the limiting boss 33 is provided on the inner wall of the valve seat 1.

[0028] To facilitate the entry of oil into the constant flow pressure reducing valve, the slide valve core 3 is provided with an oil inlet chamber 321 with an opening at the right end along the axial direction. The outer wall of the slide valve core 3 is provided with an oil inlet groove 322. The outer wall of the oil inlet chamber 321 is evenly distributed with oil inlet holes 323 that communicate with the oil inlet groove 322. The oil inlet chamber 321, the oil inlet holes 322 and the oil inlet groove 323 cooperate to form an oil inlet channel 32. The oil inlet channel 32 communicates with the oil inlet a2.

[0029] To achieve stable output flow of the constant flow pressure reducing valve, in this embodiment, the valve seat 1 is provided with a flow valve sleeve 5 that is open at the left end and hollow inside. The elastic flow valve core 4 can move axially within the flow valve sleeve 5. The outer wall of the flow valve sleeve 5 is provided with an oil outlet hole 51. Specifically, the elastic flow valve core 4 includes a valve core 42, with an oil supply hole 421 at the left end of the valve core 42. The valve core 42 is provided with a valve cavity 422 that communicates with the oil supply hole 421. A spring 43 is provided in the valve cavity 422. One end of the spring 43 abuts against the inner wall of the valve core 42, and the other end of the spring 43 abuts against the inner wall of the flow valve sleeve 5. The oil supply hole 421, the valve cavity 422, and the oil outlet hole 51 cooperate to form a throttling channel 41, wherein the diameter of the oil outlet hole 51 is greater than or equal to the diameter of the oil supply hole 421. Specifically, according to the flow pressure difference formula: In the formula, Q represents the flow rate, Cd is the valve orifice flow coefficient, A is the valve orifice flow area, and Δp is the pressure difference across the valve orifice. Generally, if the valve orifice flow area and the pressure difference across the valve orifice are determined, then the output flow rate will necessarily be constant. When oil is input from the inlet a2, the oil pushes the valve core 42 and begins to compress the spring 43. When the valve chamber 422 is filled with oil and the oil flow is stable, assuming the pressure on the left end face of the valve core 42 is P1 (i.e., the pressure in the oil inlet channel 32 is P1), the pressure in the valve chamber 422 is P2, and the compression force of the spring 43 is P3, and P1 = P2 + P3 is satisfied, at this time, the flow area of ​​the oil outlet 51 remains unchanged, and the compression of the spring 43 tends to a stable value, that is, P3 remains unchanged. Therefore, the pressure difference between the throttling channel 41 and the oil inlet channel 32 is constant, that is, the pressure difference across the oil inlet 421 is constant. At this time, the size of the oil inlet 421 is fixed, that is, the flow area of ​​the oil inlet 421 remains constant. Then the flow rate of the oil through the flow valve core 4 will remain constant, thereby keeping the flow rate at the oil outlet a1 constant. During use, if you want to adjust the output flow of the constant flow pressure reducing valve of the present invention, you can adjust the compression of the spring 43 or adjust the size of the oil supply hole 421.

[0030] To facilitate the disassembly and assembly of the flow valve sleeve 5 and the valve seat 1, the flow valve sleeve 5 and the valve seat 1 are connected by threads. At the same time, a disassembly and assembly groove 52 is provided on the right end face of the flow valve sleeve 5. Specifically, the disassembly and assembly groove 52 is either straight or cross-shaped. In this embodiment, a straight groove is preferred.

[0031] To facilitate the installation of the valve seat 1 and the elastic pressure regulating component 2, a threaded sleeve 6 is fitted on the left end of the valve seat 1. The elastic pressure regulating component 2 includes a pressure regulating rod 21 that is threadedly connected to the threaded sleeve 6. A locking nut 7 is provided on the left end of the pressure regulating rod 21 that fits against the end face of the threaded sleeve 6. The installation length of the pressure regulating rod 21 in the valve seat 1 can be adjusted, thereby adjusting the elastic force of the elastic pressure regulating component and thus adjusting the pressure reduction pressure. A pressure regulating spring 22 is fitted on the right end of the pressure regulating rod 21. A spring seat 23 is provided on the other end of the pressure regulating spring 22. A steel ball 24 for limiting the installation of the sliding valve core 3 is embedded in the spring seat 23. This design can reduce pressure fluctuations during pressure regulation. To facilitate the installation and positioning of the valve seat 1 and the pressure regulating rod 21, and to ensure the seal between the valve seat 1 and the pressure regulating rod 21, an annular boss 211 is provided on the pressure regulating rod 21. The annular boss 211 is fitted inside the valve seat 1, and a sealing groove 212 is provided on the outer wall of the annular boss 211. A retaining ring 213 and a sealing ring 214 are provided in the sealing groove 212.

[0032] To facilitate the machining of valve seat 1 and its disassembly and maintenance, valve seat 1 includes a valve seat body 11. A valve sleeve 12 is detachably connected to the right end of the valve seat body 11. In this embodiment, the valve seat body 11 and the valve sleeve 12 are connected by threads. The spool valve core 3 and the elastic flow valve core 4 are both located inside the valve sleeve 12. The oil outlet a1, oil inlet a2 and oil drain a3 are located on the valve sleeve 12 from right to left. Specifically, a stepped hole 121 is provided on the valve sleeve 12. The flow valve sleeve 5 and the stepped hole 121 cooperate to form the oil outlet a1. To facilitate machining, a tool relief groove 122 is also provided on the inner wall of the valve sleeve 12. The tool relief groove 122 is located between the spool valve core 3 and the elastic flow valve core 4.

[0033] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A constant flow pressure reducing valve characterized by: The utility model provides a valve seat (1) with hollow inside, the valve seat (1) is equipped with oil outlet (a1), oil inlet (a2) and oil drain (a3) from right to left in proper order, the left end of valve seat (1) is equipped with elastic pressure regulating component (2), the right end of elastic pressure regulating component (2) is equipped with slide valve core (3), the slide valve core (3) can move axially in the valve seat (1), the right end of slide valve core (3) is equipped with the axially movable elastic flow valve core (4), the left end of slide valve core (3) is equipped with the oil drain channel (31) that is communicated with the inner chamber of valve seat (1), the oil drain channel (31) is communicated with oil drain (a3), and the slide valve core (3) slides in the valve seat (1) and makes oil flow from oil drain (a3) to realize pressure relief, the right end of slide valve core (3) is equipped with the oil inlet channel (32) that is communicated with oil inlet (a2), the elastic flow valve core (4) is equipped with throttle channel (41) that is communicated with oil inlet channel (32), oil outlet (a1), the elastic flow valve core (4) moves in the valve seat (1), and the pressure difference between throttle channel (41) and oil inlet channel (32) remains constant, thereby realizing constant output flow. The valve seat (1) is equipped with flow valve sleeve (5) with left end opening and hollow inside, the elastic flow valve core (4) can move axially in the flow valve sleeve (5), the outer wall of flow valve sleeve (5) is equipped with oil outlet hole (51) in circumferential direction, the elastic flow valve core (4) includes valve core (42), the left end of valve core (42) is equipped with oil delivery hole (421), the valve core (42) is equipped with valve cavity (422) that is communicated with oil delivery hole (421), the valve cavity (422) is equipped with spring (43), one end of spring (43) and the inner wall of valve core (42) abut, the other end of spring (43) and the inner wall of flow valve sleeve (5) abut, oil delivery hole (421), valve cavity (422) and oil outlet hole (51) cooperate to form throttle channel (41).

2. The constant flow pressure reducing valve according to claim 1, wherein: The slide valve core (3) is equipped with oil drain cavity (311) with left end opening along the axial direction, the left end of oil drain cavity (311) is equipped with liquid inlet hole (312) that is communicated with the inner chamber of valve seat (1) along the radial direction, the outer wall of slide valve core (3) is equipped with oil drain groove (313), the right end of oil drain cavity (311) is equipped with liquid outlet hole (314) that is communicated with oil drain groove (313), and oil drain cavity (311), liquid inlet hole (312), oil drain groove (313) and liquid outlet hole (314) cooperate to form oil drain channel (31), and oil drain channel (31) is communicated with oil drain (a3).

3. The constant flow pressure reducing valve according to claim 1, wherein: The spool valve core (3) is provided with an oil inlet cavity (321) with a right end opening in the axial direction, and an oil inlet groove (322) is arranged on the outer wall of the spool valve core (3), and the outer wall of the oil inlet cavity (321) is uniformly distributed with an oil inlet hole (323) communicated with the oil inlet groove (322), and the oil inlet cavity (321), the oil inlet groove (322) and the oil inlet hole (323) cooperate to form an oil inlet channel (32), and the oil inlet channel (32) is communicated with the oil inlet (a2).

4. The constant flow pressure reducing valve of claim 1, wherein: The valve core (42) moves in the flow valve sleeve (5) to keep the pressure difference before and after the oil outlet hole (421) constant, thereby realizing constant output flow.

5. The constant flow pressure reducing valve according to claim 4, wherein: The flow valve sleeve (5) and the valve seat (1) are connected by threads, and a disassembly groove (52) is arranged on the right end face of the flow valve sleeve (5).

6. The constant flow pressure reducing valve of claim 1, wherein: The left end of the spool valve core (3) is provided with a limiting boss (33), and the inner wall of the valve seat (1) is provided with a limiting step corresponding to the limiting boss (33).

7. The constant flow pressure reducing valve of claim 1, wherein: The valve seat (1) is provided with a screw sleeve (6) at the left end, the elastic pressure regulating assembly (2) comprises a pressure regulating rod (21) screwed with the screw sleeve (6), the left end of the pressure regulating rod (21) is provided with a locking nut (7) abutting the end face of the screw sleeve (6), the right end of the pressure regulating rod (21) is provided with a pressure regulating spring (22), the other end of the pressure regulating spring (22) is provided with a spring seat (23), and the spring seat (23) is embedded with a steel ball (24) for limiting installation of the spool valve core (3).

8. The constant flow pressure reducing valve of claim 7, wherein: An annular boss (211) is arranged on the pressure regulating rod (21), the annular boss (211) is arranged in the valve seat (1), a sealing groove (212) is arranged on the outer wall of the annular boss (211), and a check ring (213) and a sealing ring (214) are arranged in the sealing groove (212).

9. The constant flow pressure reducing valve of claim 4, wherein: The valve seat (1) comprises a valve seat body (11), the valve seat body (11) is detachably connected with a valve sleeve (12) at the right end, the spool valve core (3) and the elastic flow valve core (4) are located in the valve sleeve (12), and the oil outlet (a1), the oil inlet (a2) and the oil drain (a3) are sequentially arranged on the valve sleeve (12) from right to left.

10. The constant flow pressure reducing valve of claim 9, wherein: A stepped hole (121) is arranged on the valve sleeve (12), the flow valve sleeve (5) and the stepped hole (121) cooperate to form the oil outlet (a1), and a tool withdrawal groove (122) is further arranged on the inner wall of the valve sleeve (12), and the tool withdrawal groove (122) is located between the spool valve core (3) and the elastic flow valve core (4).

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