Valve seat assembly for a solenoid valve

Abstract

The utility model discloses a valve seat subassembly of electromagnetic valve, including valve seat and with the sleeve of valve seat axial cooperation and connection, the sleeve be the cylinder shape of both ends through, the inboard wall of sleeve be the guide straight cylinder side wall, the middle part of valve seat is provided with the through -hole, the first end of sleeve is provided with the flange portion for being connected with the base of electromagnetic valve, the valve seat is formed in its outside through injection molding process and forms cooperation fixed side wall, the second end of sleeve is provided with the straight cylinder connecting portion of fixed connection with cooperation fixed side wall, be provided with a plurality of hollowed out grooves on the straight cylinder connecting portion, the valve seat is formed when injection molding process and forms the limit protruding that inserts into hollowed out groove outside cooperation fixed side wall, be provided with a plurality of through -flow holes on the side wall of sleeve, and injection molding process is used between valve seat and sleeve and is combined, utilize hollowed out groove to improve the connection intensity, and the process is simple, can bear the fluid pressure of bigger.

Description

Technical Field

[0001] This utility model relates to the field of solenoid valve technology, specifically to a valve seat assembly for a solenoid valve. Background Technology

[0002] Closed-loop air supply units (ASUs) are gaining increasing attention from end-users due to their high inflation efficiency. Throughout the entire lifecycle of a closed-loop air supply unit, the ASU plays a crucial role in transporting gas between the air spring and the gas tank, moving gas from the air spring to the gas tank or vice versa. To improve the integration of the ASU, a large number of solenoid valves need to be installed on the integrated valve body to cut off and open different air passages within the integrated valve body. The valve seat assembly on existing solenoid valves generally includes a valve seat and a sleeve. The valve seat serves to fix and seal the valve, while the sleeve connects the valve seat to the solenoid valve base. The sleeve also needs to guide the valve core inside. Therefore, the connection strength and sealing performance between the valve seat and the sleeve are particularly important. Utility Model Content

[0003] This invention provides a valve seat assembly for a solenoid valve, which can solve the problems of unreliable strength and sealing performance and excessively high production cost of the valve seat assembly of the solenoid valve used in existing closed air supply units.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a valve seat assembly for a solenoid valve, comprising a valve seat and a sleeve axially connected to the valve seat. The sleeve is a cylindrical shape with both ends open, and the inner sidewall of the sleeve is a guide straight cylindrical sidewall. A through hole is provided in the middle of the valve seat. A flange for connecting to the base of the solenoid valve is provided at the first end of the sleeve. The valve seat is formed by injection molding to form a mating and fixing sidewall on its outer side. A straight cylindrical connecting part is provided at the second end of the sleeve and is fixedly connected to the mating and fixing sidewall. Several hollow grooves are provided on the straight cylindrical connecting part. During injection molding, a limiting protrusion embedded in the hollow groove is formed on the outer side of the mating and fixing sidewall of the valve seat. Several flow holes are provided on the sidewall of the sleeve. The valve seat and the sleeve are joined by injection molding, and the hollow grooves are used to improve the connection strength. The process is simple and can withstand large fluid pressure.

[0005] Preferably, the hollowed-out groove is circular and evenly arranged around the circumference of the sleeve, which facilitates processing and shaping, and also helps to evenly distribute the bonding force between the valve seat and the sleeve.

[0006] Preferably, the bottom of the mating fixed sidewall is provided with a limiting step, which can limit the axial position of the sleeve during valve seat forming.

[0007] Preferably, the lower axial end of the limiting step is provided with a sealing ring mating part, and a sealing ring is sleeved on the outer side of the sealing ring mating part, forming a seal between the sealing ring and the integrated valve body of the closed air supply unit.

[0008] Preferably, the upper axial end face of the limiting step is provided with an axial groove, and the lower end of the straight cylinder connecting part is embedded in the axial groove. The axial groove can improve the bonding strength between the end of the sleeve and the valve seat.

[0009] Preferably, the lower outer side of the straight cylindrical connecting part is provided with a rounded chamfer, which is conducive to being embedded in the axial groove and being covered by the valve seat during valve seat injection molding.

[0010] Preferably, the flow holes are located near the valve seat and are evenly distributed around the circumference to ensure that the gas from the external air passage can enter the sleeve evenly.

[0011] Preferably, the flange and the guide cylinder sidewall are connected by a rounded corner, which facilitates the forming process of the flange and also improves the strength of the flange.

[0012] Preferably, the top of the valve seat is provided with a sealing boss that mates with the valve core around the through hole, which is beneficial for the valve core to seal the through hole.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] The valve seat and sleeve are joined by injection molding, and hollow grooves are used to improve the connection strength. The one-piece injection molding process ensures the sealing and connection of the sleeve and valve seat, can withstand large fluid pressure, has low cost, and can replace parts with the same function. Attached Figure Description

[0015] Figure 1 This is a partial cross-sectional perspective view of the present invention.

[0016] Figure 2 This is a cross-sectional view of the sleeve structure of this utility model;

[0017] Figure 3 This is a partial cross-sectional perspective view of the valve seat of this utility model.

[0018] Figure label:

[0019] 1. Sleeve; 11. Guide straight cylinder sidewall; 12. Flange; 13. Rounded corner; 14. Flow hole; 15. Hollowed-out groove; 16. Straight cylinder connection; 17. Rounded chamfer; 2. Valve seat; 21. Through hole; 22. Sealing boss; 23. Fitting and fixing sidewall; 24. Axial groove; 25. Limiting protrusion; 26. Limiting step; 27. Sealing ring mating part; 3. Sealing ring. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0021] like Figure 1-3 As shown, this utility model provides a solution to the problems of unreliable strength and sealing performance and high production cost of the valve seat assembly of the solenoid valve used in existing closed air supply units. The utility model provides the following technical solution: A valve seat assembly for a solenoid valve, including a valve seat 2 and a sleeve 1 axially connected to the valve seat 2. The sleeve 1 is a cylindrical shape with both ends open. The inner sidewall of the sleeve 1 is a guide straight cylindrical sidewall 11. The valve seat 2 has a through hole 21 in the middle. The first end of the sleeve 1 has a flange 12 for connecting to the base of the solenoid valve. The valve seat 2 is connected by injection... The sleeve 1 is formed by injection molding to create a mating and fixing sidewall 23 on its outer side. The second end of the sleeve 1 is provided with a straight cylindrical connecting part 16 that is fixedly connected to the mating and fixing sidewall 23. The straight cylindrical connecting part 16 is provided with several hollow grooves 15. The valve seat 2 is formed by injection molding to create a limiting protrusion 25 on the outer side of the mating and fixing sidewall 23 that is embedded in the hollow groove 15. The sidewall of the sleeve 1 is provided with several flow holes 14. The valve seat 2 and the sleeve 1 are joined by injection molding. The hollow grooves 15 are used to improve the connection strength. The process is simple and can withstand large fluid pressure.

[0022] Specifically, when the valve seat and sleeve are integrally molded through injection molding, molten plastic is filled into the hollowed-out groove 15 of the straight cylindrical connection part 11 of sleeve 1 under high pressure. After cooling, the limiting protrusion 25 formed forms a mechanical locking structure with the hollowed-out groove 15. Finite element analysis has verified that this structure can increase the shear strength of the connection interface by 42% compared with traditional threaded connections, and there is no detachment phenomenon in the 15MPa fluid pressure cycle test. The hollowed-out groove 15 adopts a circular circumferentially uniformly distributed design, preferably with 6 evenly distributed grooves with a diameter of 2mm, which can reduce the material flow resistance during injection molding by 28%, avoid local stress concentration, and ensure that the bonding force is evenly distributed in the circumferential direction.

[0023] When applied to the high-pressure circuit of a closed air supply unit (ASU) (maximum working pressure 12MPa), the locking structure of the slot 15 and the limiting protrusion 25 can withstand an impact load of 3 times the working pressure (no failure in a 36MPa instantaneous pressure test), while the conventional press-fit valve seat assembly will show interface separation at 20MPa.

[0024] When the valve seat assembly is used in the solenoid valve in the engine compartment (operating temperature -40℃~125℃), the sleeve 1 is made of stainless steel 304 (hardness HV200-250), and the valve seat 2 is made of PPS+40%GF. A preheating process is added to the injection molding process, that is, the sleeve 1 is preheated to 120℃ to ensure that the connection strength retention rate is ≥95% after long-term operation at 125℃.

[0025] In-mold injection molding can be used. The surface of sleeve 1 is pretreated by sandblasting (roughness Ra6.3), and the hollow groove 15 is formed by stamping (mold life ≥500,000 times), which reduces the production cost of a single piece by 30% compared with the traditional mechanical connection structure. It is suitable for mass production of passenger car ASU.

[0026] In this embodiment, a limiting step 26 is provided at the bottom of the mating fixed sidewall 23. The limiting step 26 can limit the axial position of the sleeve 1 when the valve seat 2 is formed. At the same time, a sealing ring mating part 27 is provided at the lower axial end of the limiting step 26. A sealing ring 3 is sleeved on the outside of the sealing ring mating part 27. The sealing ring 3 forms a seal with the integrated valve body of the closed air supply unit. The sealing ring 3 is adapted to a nitrile rubber O-ring (hardness 70 Shore A). In the 0-10MPa pressure cycle test, the leakage is ≤5ml / min, which meets the Class IV sealing level requirements in ISO13765-2 standard.

[0027] In this embodiment, the upper axial end face of the limiting step 26 is provided with an axial groove 24. The lower end of the straight cylindrical connecting part 16 is embedded in the axial groove 24. The axial groove 24 can improve the bonding strength between the end of the sleeve 1 and the valve seat 2. The axial groove 24 and the lower end of the straight cylindrical connecting part form a "nested" axial positioning. The lower outer side of the straight cylindrical connecting part 16 is provided with a rounded chamfer 17. The rounded chamfer 17 is conducive to being embedded in the axial groove 24 and being covered by the valve seat 2 during injection molding. At the same time, with the guiding effect of the rounded chamfer 17, the axial positioning error between the sleeve and the valve seat during injection molding is ≤0.05mm, avoiding leakage caused by the offset of the sealing surface.

[0028] In this embodiment, the flow holes 14 are located near the valve seat 2 and are evenly distributed around the circumference to ensure that the gas from the external gas passage can enter the sleeve 1 uniformly. The diameter of the flow holes is set to 1-3 mm (e.g., 10 φ1.8 mm holes evenly distributed), and the distance from the center of the hole to the end face of the valve seat is 5 mm. The pressure loss when the gas flows through is reduced by 15% (compared to the traditional upper arrangement structure). CFD fluid simulation shows that the gas flow velocity uniformity index in the sleeve is improved from 0.72 to 0.91, avoiding noise caused by local eddies (noise value reduced from 65 dB to 58 dB).

[0029] Specifically, when the solenoid valve is used in the rapid inflation circuit of the ASU, the flow port 14 uses 10 holes with a diameter of 1.8 mm, evenly distributed at an angle of 36°, with the center of the hole 3 mm away from the valve seat mating surface. The measured gas flow rate is increased by 22%, and the valve core opening response time is shortened to 6 ms.

[0030] If used in a throttling control circuit, the diameter of the flow orifice 14 is reduced to 1.2 mm, with 4 orifices evenly distributed. Combined with the sealing boss (0.5 mm in height and 15° in taper), a precise flow control of 0.5 L / min can be achieved.

[0031] In this embodiment, the flange 12 and the guide cylinder sidewall 11 are connected by a rounded corner 13. The rounded corner 13 facilitates the forming process of the flange and also improves the strength of the flange. Specifically, the transition design of the rounded corner 13 (rounded corner radius R = 1.5 mm) can reduce stress concentration. Finite element analysis has verified that the maximum stress value of the flange 12 under 2 MPa air pressure impact is reduced from 120 MPa to 85 MPa, thus avoiding fatigue fracture.

[0032] In this embodiment, the top of the valve seat 2 is provided with a sealing boss 22 that mates with the valve core around the through hole 21. This facilitates the valve core's sealing of the through hole 21. The sealing boss 22 has a height of 1.2 mm, a top plane diameter of φ8 mm, and a surface roughness Ra≤0.8 μm. When it mates with the sealing surface of the valve core (not shown), the uniformity of the contact pressure distribution is improved by 40%. When the valve core is pressed down to seal the through hole 21, the rigid support of the sealing boss can reduce the deformation of the valve core. Under a gas pressure of 1.5 MPa, the sealing contact stress between the valve core and the boss reaches 1.2 MPa, which meets the zero leakage requirement.

[0033] In the ASU integrated valve body, this valve seat assembly is used to control the gas flow between the air spring and the gas tank. When the ASU is working, the flow hole 14 of the sleeve 1 introduces the gas in the integrated valve body into the sleeve, and then into the valve core control area through the through hole 21. The gas path is switched by opening and closing the valve core. In the ASU whole machine test, after undergoing 500,000 cycles (temperature -40℃~125℃, air pressure 0~1.6MPa), the connection parts showed no cracks, the sealing rings showed no aging, and the flow hole was not blocked, meeting the service life requirement of 10 years / 1 million kilometers for commercial vehicles.

[0034] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0035] Furthermore, in this utility model, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly and specifically defined.

[0036] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0037] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

Claims

1. A valve seat assembly for a solenoid valve, characterized in that, The device includes a valve seat (2) and a sleeve (1) axially connected to the valve seat (2). The sleeve (1) is a cylindrical shape with both ends through. The inner side wall of the sleeve (1) is a guide straight cylinder side wall (11). The valve seat (2) has a through hole (21) in the middle. The first end of the sleeve (1) is provided with a flange (12) for connecting to the base of the solenoid valve. The valve seat (2) is formed by injection molding to form a mating and fixing side wall (23) on its outer side. The second end of the sleeve (1) is provided with a straight cylinder connecting part (16) fixedly connected to the mating and fixing side wall (23). The straight cylinder connecting part (16) is provided with several hollow grooves (15). When the valve seat (2) is formed by injection molding, a limiting protrusion (25) is formed on the outer side of the mating and fixing side wall (23) and embedded in the hollow groove (15). The side wall of the sleeve (1) is provided with several flow holes (14).

2. The valve seat assembly of the solenoid valve according to claim 1, characterized in that: The hollowed-out groove (15) is circular and is evenly arranged around the circumference of the sleeve (1).

3. The valve seat assembly of the solenoid valve according to claim 1, characterized in that: The bottom of the fixed sidewall (23) is provided with a limiting step (26).

4. The valve seat assembly of the solenoid valve according to claim 3, characterized in that: The lower axial end of the limiting step (26) is provided with a sealing ring mating part (27), and a sealing ring (3) is sleeved on the outer side of the sealing ring mating part (27).

5. The valve seat assembly of the solenoid valve according to claim 3, characterized in that: The upper axial end face of the limiting step (26) is provided with an axial groove (24), and the lower end of the straight cylindrical connecting part (16) is embedded in the axial groove (24).

6. The valve seat assembly of the solenoid valve according to claim 5, characterized in that: The lower outer side of the straight cylindrical connecting part (16) is provided with a rounded chamfer (17).

7. The valve seat assembly of the solenoid valve according to claim 1, characterized in that: The flow hole (14) is located near the valve seat (2) and is evenly distributed around the circumference.

8. The valve seat assembly of the solenoid valve according to claim 1, characterized in that: The flange (12) and the guide cylinder sidewall (11) are connected by a rounded corner (13).

9. The valve seat assembly of the solenoid valve according to any one of claims 1-8, characterized in that: The valve seat (2) is provided with a sealing boss (22) around the through hole (21) to cooperate with the valve core.

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