Valve needle assembly and electronic expansion valve

Abstract

The valve needle assembly comprises an outer valve needle assembly and an inner valve needle assembly, the inner valve needle assembly comprises a screw rod, a bearing and an integrated inner valve needle installed in the outer valve needle assembly in a sliding mode, an assembly hole is formed in the top of the integrated inner valve needle, the bearing is installed at an opening of the assembly hole, and the outer valve needle assembly is installed in the assembly hole. One end of the screw rod penetrates through the bearing and is in limiting connection with the bearing, the bearing and the screw rod rotate relatively, and the other end of the screw rod penetrates through the outer valve needle assembly and extends to the outer side of the outer valve needle assembly. According to the utility model, the integrated inner valve needle is adopted to replace the original split inner valve needle, so that the coaxiality of the inner valve needle can be effectively ensured, and the processing difficulty is low; an upper inner cavity, a lower inner cavity and an assembly hole of the outer valve needle assembly are communicated, and when the integrated inner valve needle moves up and down, internal pressure balance of the outer valve needle assembly and the integrated inner valve needle is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic expansion valves, in particular to a valve needle assembly and an electronic expansion valve. Background Art

[0002] The electronic expansion valve is an electromagnetically controlled component that is used in the air-conditioning system of new energy vehicles to control the on / off of the medium or adjust parameters such as the flow rate of the medium. It is generally divided into a refrigerant circuit and a coolant circuit. Under different working conditions, the demand for refrigerant flow is different.

[0003] In order to meet the requirements of different thermal management modes of new energy vehicles and to reduce the number of integrated module valves used to achieve the purpose of reducing costs, the use of double valve needle technology has become the current main technical route. At present, the inner valve needle structure of the electronic expansion valve that conventionally uses double valve needles includes an inner valve needle and an inner valve needle sleeve. The inner valve needle sleeve is installed with an inner valve needle that slides up and down. The inner valve needle sleeve is provided with an inner valve needle spring that assists the inner valve needle in resetting. The upper part of the inner valve needle sleeve is connected to a screw. This split inner valve needle structure has the problem of poor coaxiality and requires high assembly accuracy. Therefore, it is necessary to design a double valve needle structure using an integrated inner valve needle, and it is necessary to consider the connection between the integrated inner valve needle and the valve stem and the internal pressure balance. Summary of the invention

[0004] The technical problem to be solved by the utility model is to provide a valve needle assembly and an electronic expansion valve, which adopts an integrated inner valve needle to replace the original split inner valve needle, which can not only effectively ensure the coaxiality of the inner valve needle but also has less processing difficulty; the upper inner cavity, the lower inner cavity and the assembly hole of the outer valve needle assembly are connected, and when the integrated inner valve needle moves up and down, this arrangement is conducive to achieving internal pressure balance of the outer valve needle assembly and the integrated inner valve needle.

[0005] The technical solution adopted by the utility model to solve its technical problems is: to provide a valve needle assembly, including an outer valve needle assembly and an inner valve needle assembly, the inner valve needle assembly including a screw, a bearing and an integrated inner valve needle slidably installed inside the outer valve needle assembly, the top of the integrated inner valve needle is provided with an assembly hole, a bearing is installed at the opening of the assembly hole, one end of the screw passes through the bearing and is limitedly connected to the bearing, the bearing and the screw rotate relative to each other, and the other end of the screw passes through the outer valve needle assembly and extends to the outside of the outer valve needle assembly.

[0006] As a supplement to the technical solution described in the utility model, a valve needle spring is installed at the upper end of the outer valve needle assembly, and the valve needle spring is sleeved on the outside of the screw rod.

[0007] As a supplement to the technical solution described in the utility model, a through hole for the screw to pass through is opened at the upper end of the outer valve needle assembly, a circle of limiting convex ring is arranged around the through hole on the outer valve needle assembly, and the valve needle spring is sleeved on the outside of the limiting convex ring.

[0008] As a supplement to the technical solution described in the utility model, a bearing retaining ring is installed on the outer side of the assembly hole opening at the upper end of the integrated internal valve needle, and the bearing retaining ring is used to limit the outer ring of the bearing. One end of the screw rod passes through the bearing retaining ring and the bearing in sequence and is inserted into the assembly hole and an inner ring retaining ring is provided at the end. A preload spring and a sleeve are sleeved on the screw rod, one end of the preload spring is connected to the screw rod for limiting, the other end of the preload spring presses against the sleeve, and one end of the sleeve presses against the inner ring of the bearing.

[0009] As a supplement to the technical solution described in the utility model, a circle of annular protrusions is arranged on the upper end of the inner valve needle around the upper port of the assembly hole, and the bearing retaining ring is sleeved outside the annular protrusion. The bearing retaining ring and the annular protrusion are fixed together by interference fit and welding.

[0010] As a supplement to the technical solution described in the utility model, the screw and the inner ring retaining ring are fixed together through interference fit and welding.

[0011] As a supplement to the technical solution described in the utility model, a circle of limiting steps is arranged on the screw rod, and the limiting step supports one end of the preload spring.

[0012] As a supplement to the technical solution described in the utility model, an embedding groove is provided at the opening of the assembly hole, and the bearing is installed in the embedding groove, and the outer ring of the bearing is tightly fitted with the inner wall of the embedding groove.

[0013] As a supplement to the technical solution described in the utility model, an opening is provided at the bottom of the outer valve needle assembly, a side hole connected to the opening is provided on the side of the lower part of the outer valve needle assembly, and the lower end of the integrated inner valve needle has a sealing part that cooperates with the opening.

[0014] As a supplement to the technical solution described in the utility model, at least one side plane is arranged on the upper side of the one-piece inner valve needle, an air outlet is opened on the side plane, and a circle of avoidance steps is arranged on the lower part of the one-piece inner valve needle, an air vent is arranged on the avoidance step, and the air vent and the air outlet are both connected with the assembly hole. The structure is conducive to achieving the internal pressure balance of the inner valve needle, and the gas can be delivered into the upper end of the valve body as soon as possible, so as to achieve the internal balance more quickly.

[0015] As a supplement to the technical solution described in the utility model, there are two side planes, which are respectively located on both sides of the upper part of the integrated inner valve needle.

[0016] An electronic expansion valve comprises the valve needle assembly.

[0017] Beneficial effect: The utility model relates to a valve needle assembly and an electronic expansion valve, which adopts an integrated inner valve needle to replace the original split inner valve needle, which can not only effectively ensure the coaxiality of the inner valve needle but also has less processing difficulty; at least one side plane is arranged on the upper side of the integrated inner valve needle, an upper flow gap is formed between the side plane and the inner wall of the outer valve needle assembly, an air outlet is arranged on the side plane, and a circle of avoidance steps is arranged on the lower part of the integrated inner valve needle, a lower flow gap is formed between the avoidance step and the inner wall of the outer valve needle assembly, an air vent is arranged on the avoidance step, the air vent and the air outlet are both connected with the assembly hole, and the upper inner cavity, the lower inner cavity and the assembly hole of the outer valve needle assembly are connected through the upper flow gap, the lower flow gap, the air vent and the air outlet and other structures. When the integrated inner valve needle moves up and down, such an arrangement is conducive to achieving internal pressure balance of the outer valve needle assembly and the integrated inner valve needle. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the installation diagram of the utility model;

[0019] Figure 2 It is a cross-sectional view of the utility model;

[0020] Figure 3 This utility model Figure 2 A partial enlarged view of

[0021] Figure 4 It is a structural schematic diagram of the integrated inner valve needle described in the utility model.

[0022] Illustration: 1. Valve seat assembly, 2. Nut assembly, 3. Valve needle spring, 4. Outer valve needle assembly, 5. Inner valve needle assembly, 6. Valve port, 7. Hollow, 8. Magnetic rotor assembly, 9. Screw, 10. Bearing retaining ring, 11. Integrated inner valve needle, 12. Assembly hole, 13. Inner ring retaining ring, 14. Bearing, 15. Opening, 16. Preload spring, 17. Limit step, 18. Bushing, 19. Through hole, 20. Limit convex ring, 21. Annular protrusion, 22. Embedded groove, 23. Side plane, 24. Air outlet, 25. Vent, 26. Avoidance step, 27. Side hole, 28. Sealing part. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

[0024] The embodiments of the present utility model relate to a valve needle assembly and an electronic expansion valve, such as Figure 1-4 As shown, the electronic expansion valve includes a valve seat assembly 1, a valve needle assembly, a nut assembly and a magnetic rotor assembly 8. The valve seat assembly 1 is internally installed with a valve needle assembly, and the valve seat assembly 1 is upperly installed with a nut assembly. When the electronic expansion valve starts to work, the magnetic rotor assembly 8 rotates under the action of the excitation magnetic field, thereby driving the screw 9 to rotate. The nut assembly is threadedly connected to the screw 9, further driving the valve needle assembly to move, so as to realize the opening change of the valve port of the electronic expansion valve, thereby achieving the purpose of regulating the flow and pressure of the fluid medium.

[0025] The valve needle assembly includes an outer valve needle assembly 4 and an inner valve needle assembly 5. The inner valve needle assembly 5 includes a screw rod 9, a bearing 14 and an integrated inner valve needle 11 slidably mounted inside the outer valve needle assembly 4. An assembly hole 12 is provided at the top of the integrated inner valve needle 11. A bearing 14 is installed at the opening of the assembly hole 12. One end of the screw rod 9 passes through the bearing 14 and is limitedly connected to the bearing 14. The bearing 14 and the screw rod 9 rotate relative to each other. The other end of the screw rod 9 passes through the outer valve needle assembly 4 and extends to the outside of the outer valve needle assembly 4.

[0026] The utility model adopts an integrated inner valve needle 11 to replace the original split inner valve needle, which can not only effectively ensure the coaxiality of the inner valve needle but also has low processing difficulty.

[0027] Reference Figure 2 and Figure 3 As shown, the outer valve needle assembly 4 is provided with an opening 15 at the bottom, and a side hole 27 connected to the opening 15 is provided on the side of the lower part of the outer valve needle assembly 4. The lower end of the integrated inner valve needle 11 has a sealing portion 28 that cooperates with the opening 15, and the lower part of the sealing portion 28 is truncated cone-shaped; the outer valve needle assembly 4 is composed of an outer valve needle and a valve needle sleeve, and the opening 15 and the side hole 27 are both provided on the outer valve needle, and the outer valve needle and the valve needle sleeve are fixed together by interference fit and welding.

[0028] The bottom of the valve seat assembly 1 is provided with a valve port 6, and the side of the valve seat assembly 1 is provided with a hollow 7 connected to the valve port 6. When the screw 9 rotates, the integrated inner valve needle 11 will move upward with the screw 9, and the outer valve needle assembly 4 is kept stationary by the valve needle spring 3. The axial movement of the integrated inner valve needle 11 and the blocking portion 28 opens the opening 15, and the medium enters from the opening 15 and then goes out through the side hole 27. The gap between the sealing surface of the blocking portion 28 and the sealing surface of the opening 15 is changed by controlling the up and down movement of the integrated inner valve needle 11, so as to achieve the effect of regulating a small flow rate; after the upper end of the integrated inner valve needle 11 presses against the outer valve needle assembly 4, as the screw 9 rotates, the outer valve needle assembly 4 will move upward with the integrated inner valve needle 11, and the gap between the sealing surface of the lower end of the outer valve needle assembly 4 and the sealing surface of the valve port 6 is changed by controlling the up and down movement of the outer valve needle assembly 4, so as to achieve the effect of regulating a large flow rate.

[0029] Reference Figure 2 and Figure 3 As shown, a valve needle spring 3 is installed on the upper end of the outer valve needle assembly 4, and the valve needle spring 3 is sleeved on the outside of the screw 9, and the nut assembly supports the upper end of the valve needle spring 3; a through hole 19 for the screw 9 to pass through is opened on the upper end of the outer valve needle assembly 4, and a circle of limiting convex rings 20 are arranged around the through hole 19 on the outer valve needle assembly 4, and the valve needle spring 3 is sleeved on the outside of the limiting convex ring 20, and the lower end of the valve needle spring 3 is limited by the limiting convex ring 20.

[0030] The upper end of the integrated inner valve needle 11 is located on the outside of the opening of the assembly hole 12 and is installed with a bearing retaining ring 10, which is used to limit the outer ring of the bearing 14. One end of the screw 9 passes through the bearing retaining ring 10 and the bearing 14 in turn and is inserted into the assembly hole 12 and is provided with an inner ring retaining ring 13 at the end. A preload spring 16 and a sleeve 18 are sleeved on the screw 9. One end of the preload spring 16 is connected to the screw 9 for limiting position, and the other end of the preload spring 16 presses against the sleeve 18, and one end of the sleeve 18 presses against the inner ring of the bearing 14.

[0031] The utility model installs the bearing 14 in the assembly hole 12, the outer ring of the bearing 14 is tightly matched with the inner wall of the assembly hole 12, the outer side of the bearing 14 is limited by the bearing retaining ring 10, the inner ring of the bearing 14 is fitted with the shaft sleeve 18, the preload spring 16 arranged on the screw 9 supports the shaft sleeve 18, and a certain upper and lower movable gap is arranged between the shaft sleeve 18 and the screw 9, the lower end of the screw 9 is connected and fixed with the inner ring retaining ring 13, the inner ring retaining ring 13 is fitted with the inner ring of the bearing 14, and the bearing 14 moves with the rotation of the screw 9, thereby reducing friction, extending service life, facilitating assembly, and having a stable structure.

[0032] The upper end of the inner valve needle 2 is provided with a circle of annular protrusions 21 around the upper end of the assembly hole 12, and the bearing retaining ring 10 is sleeved outside the annular protrusions 21. The bearing retaining ring 10 and the annular protrusions 21 are fixed together by interference fit and welding.

[0033] As an installation instruction of the inner ring retaining ring 13, the screw rod 9 and the inner ring retaining ring 13 are fixed together by interference fit and welding, which can effectively ensure the connection strength and structural stability between the two.

[0034] As a description of the limit of the upper end of the preload spring 16 , a circle of limit steps 17 are arranged on the screw rod 9 , and the upper end of the preload spring 16 is supported by the limit steps 17 .

[0035] As an illustration of the embedded installation of the bearing 14 , an embedding groove 22 is provided at the opening of the assembly hole 12 , and the bearing 14 is installed in the embedding groove 22 , and the outer ring of the bearing 14 is tightly fitted with the inner wall of the embedding groove 22 .

[0036] When the integrated inner valve needle 11 is assembled with the screw rod 9, the preload spring 16, the sleeve 18, the bearing retaining ring 10, the bearing 14 and the inner ring retaining ring 13 are first inserted into the screw rod 9 in sequence, and then the screw rod 9 and the inner ring retaining ring 13 are fixed by interference fit and welding, and then the sleeve 18 is installed into the embedded groove 22, and the outer ring of the bearing 14 is tightly fitted with the inner wall of the slot 13, and then the bearing retaining ring 10 is sleeved on the outside of the annular protrusion 21, and the bearing retaining ring 10 and the annular protrusion 21 are fixed by interference fit and welding, and the upper end of the preload spring 16 is supported by the limiting step 17, and the lower end of the preload spring 16 is supported by the sleeve 18, and one end of the sleeve 18 passes through the bearing retaining ring 10 to support the inner ring of the bearing 14, so that the entire bearing is installed and fixed, and the assembly is convenient.

[0037] Reference Figure 4 As shown, at least one side plane 23 is provided on the upper side of the one-piece inner valve needle 11, and an upper flow gap is formed between the side plane 23 and the inner wall of the outer valve needle assembly 4, and an air outlet hole 24 is provided on the side plane 23. A circle of avoidance steps 26 is provided at the lower part of the one-piece inner valve needle 11, and a lower flow gap is formed between the avoidance step 26 and the inner wall of the outer valve needle assembly 4, and an air vent 25 is provided on the avoidance step 26. The air vent 25 and the air outlet hole 24 are both connected to the assembly hole 12. Through the upper flow gap, the lower flow gap, the air vent 25 and the air outlet hole 24 and other structures, the upper inner cavity, the lower inner cavity and the assembly hole 12 of the outer valve needle assembly 4 are connected. When the one-piece inner valve needle 11 moves up and down, such a configuration is conducive to achieving internal pressure balance of the outer valve needle assembly 4 and the one-piece inner valve needle 11.

[0038] In a preferred embodiment, there are two side planes 23 , which are respectively located on both sides of the upper portion of the integrated inner valve needle 11 .

[0039] An electronic expansion valve comprises the valve needle assembly.

[0040] In the description of the present utility model, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present utility model; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0041] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0042] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0043] The above is a detailed introduction to a valve needle assembly and an electronic expansion valve provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A valve needle assembly, comprising an outer valve needle assembly (4) and an inner valve needle assembly (5), characterized in that: The inner valve needle assembly (5) comprises a screw (9), a bearing (14) and an integrated inner valve needle (11) slidably mounted inside the outer valve needle assembly (4); an assembly hole (12) is provided at the top of the integrated inner valve needle (11); a bearing (14) is mounted at the opening of the assembly hole (12); one end of the screw (9) passes through the bearing (14) and is positionally connected to the bearing (14); the bearing (14) and the screw (9) rotate relative to each other; the other end of the screw (9) passes through the outer valve needle assembly (4) and extends to the outside of the outer valve needle assembly (4).

2. A valve needle assembly according to claim 1, characterized in that: A valve needle spring (3) is installed at the upper end of the outer valve needle assembly (4), and the valve needle spring (3) is sleeved on the outside of the screw rod (9).

3. A valve needle assembly according to claim 2, characterized in that: The upper end of the outer valve needle assembly (4) is provided with a through hole (19) for the screw rod (9) to pass through, and a circle of limiting convex ring (20) is arranged around the through hole (19) on the outer valve needle assembly (4), and the valve needle spring (3) is sleeved on the outside of the limiting convex ring (20).

4. A valve needle assembly according to claim 1, characterized in that: The upper end of the integrated inner valve needle (11) is located on the outside of the opening of the assembly hole (12) and is installed with a bearing retaining ring (10), which is used to limit the outer ring of the bearing (14). One end of the screw rod (9) passes through the bearing retaining ring (10) and the bearing (14) in sequence and is inserted into the assembly hole (12) and is provided with an inner ring retaining ring (13) at the end. A preload spring (16) and a shaft sleeve (18) are sleeved on the screw rod (9), one end of the preload spring (16) is connected to the screw rod (9) in a limiting manner, the other end of the preload spring (16) presses against the shaft sleeve (18), and one end of the shaft sleeve (18) presses against the inner ring of the bearing (14).

5. A valve needle assembly according to claim 4, characterized in that: The upper end of the inner valve needle (2) is provided with a circle of annular protrusions (21) around the upper end of the assembly hole (12), and the bearing retaining ring (10) is sleeved outside the annular protrusions (21). The bearing retaining ring (10) and the annular protrusions (21) are fixed together by interference fit and welding.

6. A valve needle assembly according to claim 4, characterized in that: A circle of limiting steps (17) is arranged on the screw rod (9), and the limiting steps (17) press against one end of the preload spring (16).

7. A valve needle assembly according to claim 1, characterized in that: The outer valve needle assembly (4) has an opening (15) at the bottom, and a side hole (27) connected to the opening (15) is formed on the side of the lower part of the outer valve needle assembly (4). The lower end of the integrated inner valve needle (11) has a sealing portion (28) that cooperates with the opening (15).

8. The valve needle assembly according to claim 1, characterized in that: The upper side of the integrated inner valve needle (11) is provided with at least one side plane (23), and an air outlet hole (24) is provided on the side plane (23). The lower part of the integrated inner valve needle (11) is provided with a circle of avoidance steps (26), and an air vent (25) is provided on the avoidance step (26). The air vent (25) and the air outlet hole (24) are both connected to the assembly hole (12).

9. A valve needle assembly according to claim 8, characterized in that: There are two side planes (23), which are respectively located on two sides of the upper part of the integrated inner valve needle (11).

10. An electronic expansion valve, characterized in that: The electronic expansion valve comprises a valve needle assembly as claimed in any one of claims 1 to 9.

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