Low-pressure large-flow tee-shaped proportional pressure reducing valve

Abstract

The application provides a low-pressure large-flow three-way proportional pressure reducing valve, which comprises a valve sleeve, a valve core, a proportional electromagnet and a push rod, the valve core is installed in the valve sleeve and can slide in the valve sleeve, one end of the valve core is in contact with the end surface of the push rod, the push rod is installed in the proportional electromagnet, the proportional electromagnet is connected with the valve sleeve, the valve sleeve is provided with an oil inlet P and an oil return port T, an annular groove is arranged at the middle position of the valve core, the annular groove forms a throttling port with the oil inlet P and the oil return port T, and the area between the valve core and the valve sleeve near the proportional electromagnet forms a control cavity. The three-way proportional pressure reducing valve of the application realizes large-flow output of the working oil port under the condition that the rated output pressure is unchanged, and further improves the response performance of the three-way proportional pressure reducing valve; the application controls the pressure at the working oil port A by controlling the excitation current of the proportional electromagnet.

Description

Technical Field

[0001] This invention relates to the field of pressure reducing valve technology, and in particular to a low-pressure, high-flow three-way proportional pressure reducing valve. Background Technology

[0002] The three-way proportional pressure reducing valve can proportionally convert the excitation current into the control pressure output. It is one of the core control components in the hydraulic system and is widely used in engineering machinery, automobiles and other fields.

[0003] Due to design limitations in the valve core and valve sleeve, existing cartridge-type direct-acting three-way proportional pressure reducing valves on the market can only achieve low-pressure, low-flow output. The smaller flow output means a slower response speed, which seriously restricts the further improvement of the performance of proportional pressure reducing valves. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a low-pressure, high-flow three-way proportional pressure reducing valve. This invention can increase the output flow while maintaining the rated output pressure unchanged, thereby further improving the response performance of the proportional pressure reducing valve.

[0005] The technical solution of the present invention is as follows: a low-pressure, high-flow three-way proportional pressure reducing valve, comprising a valve sleeve, a valve core, a proportional electromagnet, and a push rod. The valve core is installed inside the valve sleeve and can slide within the valve sleeve. One end of the valve core is in contact with the end face of the push rod. The push rod is installed inside the proportional electromagnet. The proportional electromagnet is connected to the valve sleeve. The valve sleeve is provided with an oil inlet P and an oil return port T. An annular groove is also provided in the middle of the valve core. The annular groove, the oil inlet P, and the oil return port T form a throttling orifice. The area between the valve core and the valve sleeve near the proportional electromagnet forms a control cavity.

[0006] Preferably, the valve sleeve is provided with a stepped through hole that extends through both ends, the valve core is installed in the stepped through hole, and the diameter of the stepped through hole near the proportional electromagnet is smaller than the diameter of the end away from the proportional electromagnet, and the end away from the proportional electromagnet serves as the working oil port A.

[0007] Preferably, the return port T is located on the valve sleeve near the proportional electromagnet, and the inlet port P is located on the valve sleeve away from the proportional electromagnet.

[0008] Preferably, the valve sleeve is further provided with multiple annular grooves, and a corresponding sealing ring is fitted inside the annular grooves.

[0009] Preferably, the valve sleeve is further provided with a first connecting hole, the two ends of which are respectively connected to the oil return port T and the internal cavity of the proportional electromagnet.

[0010] Preferably, the valve core has a blind hole along its length, and the valve core at the control cavity position also has a first through hole along the vertical direction. The first through hole communicates with the blind hole, and the first through hole and the blind hole are used to connect the working oil port A and the annular groove.

[0011] Preferably, the valve core near the working port A is provided with a plurality of second through holes along its length, the second through holes being used to connect the working port A with the annular groove.

[0012] Preferably, a return spring is also fitted on one end of the valve core near the push rod, and the other end of the return spring abuts against the stepped groove inside the valve sleeve, and the other end of the return spring abuts against the spring seat provided on the valve core.

[0013] Preferably, the valve sleeve and the proportional electromagnet are connected by rolling.

[0014] Preferably, a sealing ring is also provided at the connection between the valve sleeve and the proportional electromagnet.

[0015] Preferably, the valve core is further provided with a retaining ring, which is located between the large and small diameters of the stepped through hole inside the spring seat, thereby restricting the sliding position of the spring seat.

[0016] Preferably, the proportional electromagnet is further provided with a housing on its outer side.

[0017] The beneficial effects of this invention are as follows:

[0018] 1. The three-way proportional pressure reducing valve of the present invention achieves a large flow rate output at the working port while ensuring that the rated output pressure remains unchanged, thereby further improving the response performance of the three-way proportional pressure reducing valve.

[0019] 2. This invention controls the pressure at the working port A by controlling the magnitude of the excitation current of the proportional electromagnet, thereby effectively improving the response speed of the three-way proportional pressure reducing valve. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the pressure reducing valve of the present invention;

[0021] Figure 2 This is a cross-sectional schematic diagram of the pressure reducing valve of the present invention;

[0022] Figure 3 This is a schematic diagram of the valve sleeve of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of the present invention after the valve sleeve is concealed;

[0024] Figure 5 This is a schematic diagram of the valve core structure of the present invention;

[0025] Figure 6 This is a partially enlarged view of the valve core of the present invention;

[0026] Figure 7 This is a schematic diagram of the working position of the pressure reducing valve of the present invention;

[0027] In the diagram, 1-valve sleeve, 2-valve core, 3-proportional electromagnet, 4-push rod, 5-housing shell;

[0028] 11-Control chamber; 12-Oil inlet P; 13-Oil return port T; 14-Stepped through hole; 15-Working oil port A; 16-Annular groove; 17-Sealing ring; 18-First connecting hole.

[0029] 21-Reset spring, 22-Spring seat, 23-Annular groove, 24-Blind hole, 25-First through hole, 26-Second through hole, 27-Snap ring. Detailed Implementation

[0030] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings:

[0031] like Figure 1-2 As shown, this embodiment provides a low-pressure, high-flow three-way proportional pressure reducing valve, including a valve sleeve 1, a valve core 2, a proportional electromagnet 3, and a push rod 4. The valve core 2 is installed inside the valve sleeve 1 and can slide within the valve sleeve 1. One end of the valve core 2 contacts the end face of the push rod 4. The push rod 4 is installed inside the proportional electromagnet 3. The proportional electromagnet 3 and the valve sleeve 1 are connected by a rolling connection. The valve sleeve 1 is provided with multiple oil inlets P12 and multiple oil return ports T13. The valve core 2 is also provided with an annular groove 23 in the middle. The annular groove 23 forms a throttling orifice with the multiple oil inlets P12 and the multiple oil return ports T13. The area between the valve core 2 and the valve sleeve 1 near the proportional electromagnet 3 forms a control cavity 11.

[0032] As a preferred embodiment, such as Figure 2 , 3 As shown, the valve sleeve 1 is provided with a stepped through hole 14 that runs through both ends. The valve core 2 is installed in the stepped through hole 14. The diameter of the stepped through hole 14 near the proportional electromagnet 3 is smaller than the diameter of the end away from the proportional electromagnet 3. The end away from the proportional electromagnet 3 serves as the working oil port A15.

[0033] As a preferred embodiment, such as Figure 2 , 3 As shown, the return port T13 is located on the valve sleeve 1 near the end of the proportional electromagnet 3, and the inlet port P12 is located on the valve sleeve 1 away from the end of the proportional electromagnet 3.

[0034] As a preferred embodiment, such as Figure 2 , 3 As shown, the valve sleeve 1 is also provided with a plurality of annular grooves 16, and a corresponding sealing ring 17 is fitted inside the annular grooves 16.

[0035] As a preferred embodiment, such as Figure 2 , 3 As shown, the valve sleeve 1 is also provided with a first connecting hole 18, and the two ends of the first connecting hole 18 are respectively connected to the oil return port T13 and the internal cavity of the proportional electromagnet 3.

[0036] As a preferred embodiment, such as Figure 2 , 4 As shown in Figure 5, the valve core 2 has a blind hole 24 along its length. The valve core 2 at the position of the control cavity 11 also has a first through hole 25 along the vertical direction. The first through hole 25 is connected to the blind hole 24. The first through hole 25 and the blind hole 24 are used to connect the working oil port A15 and the annular groove 23.

[0037] As a preferred embodiment, such as Figure 2 , 4 As shown in Figure 5, a plurality of second through holes 26 are also provided along the length direction on the valve core 2 near the working oil port A15. The second through holes 26 are used to connect the working oil port A15 and the annular groove 23.

[0038] As a preferred embodiment, such as Figure 2 , 4 As shown in Figures 5 and 6, a return spring 21 is also sleeved on one end of the valve core 2 near the push rod 4. The other end of the return spring 21 abuts against the stepped groove inside the valve sleeve 1, and the other end of the return spring 21 abuts against the spring seat 22 provided on the valve core 2.

[0039] As a preferred embodiment, such as Figure 1 , 2 As shown, a sealing ring 17 is also fitted at the connection between the valve sleeve 1 and the proportional electromagnet 3.

[0040] As a preferred embodiment, such as Figure 6 As shown, the valve core 2 is also provided with a retaining ring 27, which is located between the large and small diameters of the stepped through hole 14 inside the spring seat 22, thereby restricting the sliding position of the spring seat 22.

[0041] As a preferred embodiment, such as Figure 1 As shown, a housing 5 is also provided on the outside of the proportional electromagnet 3.

[0042] Working principle:

[0043] When the proportional electromagnet 3 is not energized, the valve core 2 is located on the far right under the action of the return spring 21, and is in close contact with the push rod 4. At this time, the return port T13 is connected to the working port A15 through the annular groove 23 and the second through hole 26, and the control cavity 11 is connected to the working port A15 through the first through hole 25 and the blind hole 24. At this time, the pressure at the working port A15 is the minimum, which is equal to the pressure at the return port T13.

[0044] When the proportional electromagnet 3 receives an input current, it generates a corresponding electromagnetic force. Under the action of this electromagnetic force, the valve core 2 overcomes the spring force of the return spring 21 and moves to the left, causing the annular groove 23 to move to the oil inlet P12. The working oil port A15 is connected to the oil inlet P12 through the second through hole 26 and the annular groove 23, and also connected to the control chamber 11 through the blind hole 24 and the first through hole 25. The return oil port T13 is closed. At this time, the pressure in the working oil port A15 and the control chamber 11 will increase under the action of the oil inlet P12. When the pressure increases to a certain level, the valve core 2 moves to the right, and the spring force of the return spring 21, the electromagnetic force of the proportional electromagnet 3, the feedback fluid pressure at the working oil port A15, and the feedback fluid pressure at the control chamber 11 reach a new equilibrium at the new position. Figure 7 As shown. At this time, the working port A15, the return port T13, and the inlet port P12 are all in a cut-off state, and a certain pressure can be maintained at the working port A15. As the excitation current increases, the electromagnetic force output by the proportional electromagnet 3 also increases, eventually causing the pressure at the working port A15 to increase proportionally. Through the above process, the proportional pressure reducing valve achieves proportional control of the output pressure.

[0045] At this time, the force balance equation of the valve core 2 is:

[0046]

[0047] In the formula, F s The spring force F is the return spring 21. e p is the electromagnetic force output by proportional electromagnet 3. A The pressure at the working oil port A15 is denoted by D; the diameter of the large diameter end face of valve core 2 is denoted by d; and the height of control chamber 11 is denoted by d.

[0048] The electromagnetic force F generated by the proportional electromagnet 3 e The approximate relationship with the excitation current i is:

[0049] F e =k*i;

[0050] In the formula, k is the proportionality coefficient between the output electromagnetic force of the proportional electromagnet 3 and the excitation current, and its value is positive; i is the excitation current of the proportional electromagnet 3.

[0051] The spring force F of the reset spring 21 s for:

[0052] F s =k s *Δx2;

[0053] In the formula, k s Δx2 represents the spring stiffness of the return spring 21; Δx2 represents the compression of the return spring 21.

[0054] Therefore, the pressure at the working oil port A15 can be expressed as:

[0055]

[0056] Since the structures of valve core 2 and valve sleeve 1 are fixed, the large-diameter end face diameter D of valve core 2 and the height d of control cavity 11 are constant values.

[0057] Due to the compression Δx2 of the return spring 21 and the stiffness k of the return spring 21 s The force is very small, so the spring force of the return spring 21 can be approximated as constant.

[0058] Therefore, as the excitation current i of the proportional electromagnet 3 continuously increases, the pressure p at the working oil port A15 increases. A Increase proportionally.

[0059] The embodiments and descriptions above are merely illustrative of the principles and preferred embodiments of the present invention. Various changes and modifications may be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A low-pressure, high-flow three-way proportional pressure reducing valve, characterized in that: The device includes a valve sleeve (1), a valve core (2), a proportional electromagnet (3), and a push rod (4). The valve core (2) is installed inside the valve sleeve (1) and can slide inside the valve sleeve (1). One end of the valve core (2) is in contact with the end face of the push rod (4). The push rod (4) is installed inside the proportional electromagnet (3). The proportional electromagnet (3) and the valve sleeve (1) are connected by a rolling connection. The valve sleeve (1) is provided with multiple oil inlets P (12) and multiple oil return ports T (13), and the end of the valve sleeve (1) is also provided with a working oil port A; The valve core (2) is also provided with an annular groove (23) in the middle position. The annular groove (23) forms a throttling port with multiple oil inlets P (12) and multiple oil return ports T (13). The area between the valve core (2) and the valve sleeve (1) near the position of the proportional electromagnet (3) forms a control cavity (11). The valve core (2) is provided with a blind hole (24) along its length. The valve core (2) at the position of the control cavity (11) is also provided with a first through hole (25) along the vertical direction. The first through hole (25) is connected to the blind hole (24). The first through hole (25) and the blind hole (24) are used to connect the working oil port A (15) and the control cavity (11). The valve core (2) located near the working oil port A (15) is also provided with a number of second through holes (26) along the length direction. The second through holes (26) are used to connect the working oil port A (15) and the annular groove (23). A return spring (21) is also sleeved on one end of the valve core (2) near the push rod (4). One end of the return spring (21) abuts against the stepped groove inside the valve sleeve (1), and the other end of the return spring (21) abuts against the spring seat (22) provided on the valve core (2). The valve core (2) is also provided with a retaining ring (27), which is located between the large and small diameters of the stepped through hole (14) inside the spring seat (22), thereby restricting the sliding position of the spring seat (22); The force balance equation of the valve core (2) is: ; In the formula, The spring force of the reset spring; The electromagnetic force output by the proportional electromagnet; d is the pressure at working port A; D is the large diameter end face diameter of the valve core; d is the height of the control chamber. Electromagnetic force The approximate relationship with the excitation current i is: In the formula, k is the proportionality coefficient between the output electromagnetic force of the proportional electromagnet and the excitation current, and its value is positive; i is the excitation current of the proportional electromagnet. Spring force of the return spring (21) for: ; In the formula, The spring stiffness of the reset spring; This is the compression of the return spring; The pressure at working port A (15) is: ; The large-diameter end face diameter D of the valve core (2) and the height d of the control cavity (11) are constants, and the compression of the return spring (21) is... and the stiffness of the return spring (21) The spring force of the return spring (21) is very small and approximately constant. As the excitation current i of the proportional electromagnet (3) increases, the pressure at the working oil port A (15) increases. Increase proportionally.

2. The low-pressure, high-flow three-way proportional pressure reducing valve according to claim 1, characterized in that: The valve sleeve (1) is provided with a stepped through hole (14) that runs through both ends, and the valve core (2) is installed in the stepped through hole (14).

3. The low-pressure, high-flow three-way proportional pressure reducing valve according to claim 2, characterized in that: The diameter of the stepped through hole (14) near the proportional electromagnet (3) is smaller than the diameter of the end away from the proportional electromagnet (3), and the end away from the proportional electromagnet (3) serves as the working oil port A (15).

4. The low-pressure, high-flow three-way proportional pressure reducing valve according to claim 1, characterized in that: The return port T (13) is located on the valve sleeve (1) near the end of the proportional electromagnet (3), and the inlet port P (12) is located on the valve sleeve (1) away from the end of the proportional electromagnet (3).

5. A low-pressure, high-flow three-way proportional pressure reducing valve according to claim 4, characterized in that: The valve sleeve (1) is also provided with a plurality of annular grooves (16), and a corresponding sealing ring (17) is fitted inside the annular grooves (16).

6. A low-pressure, high-flow three-way proportional pressure reducing valve according to claim 5, characterized in that: The valve sleeve (1) is also provided with a first connection hole (18), and the two ends of the first connection hole (18) are respectively connected to the oil return port T (13) and the internal cavity of the proportional electromagnet (3).

7. A low-pressure, high-flow three-way proportional pressure reducing valve according to claim 1, characterized in that: A sealing ring (17) is also provided at the connection between the valve sleeve (1) and the proportional electromagnet (3).

8. A low-pressure, high-flow three-way proportional pressure reducing valve according to claim 1, characterized in that: The proportional electromagnet (3) is used to generate an electromagnetic force that is positively correlated with the excitation current, and the proportional electromagnet (3) is also fitted with a shell (5) on its outer side.

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