Valve needle assembly and electronic expansion valve

Abstract

The present disclosure relates to the technical field of valves. Provided are a valve needle assembly and an electronic expansion valve. The valve needle assembly comprises a valve needle body, a bushing and a sealing structure, wherein the valve needle body comprises an adjusting portion and a fixing portion; the adjusting portion is configured to selectively block a valve port; in the axial direction of the adjusting portion, one side of the fixing portion is connected to the adjusting portion, and a fixing groove is provided on the other side of the fixing portion; the bushing is sleeved outside the valve needle body; in an axial direction of the adjusting portion, a limiting portion is provided at the end of the bushing away from the adjusting portion, and the limiting portion is configured to be bendable in a radial direction of the adjusting portion toward the fixing groove, such that the limiting portion is arranged in the fixing groove; and the sealing structure is sleeved outside the valve needle body and arranged between the valve needle body and the bushing. By using a riveting method, heat generation is avoided, the risk of heat deformation of the sealing structure is reduced, and the sealing effect of the valve needle assembly is improved, thereby improving the use reliability of the sealing structure.

Description

Valve needle assembly and electronic expansion valve

[0001] Cross-referencing

[0002] This disclosure claims priority to Chinese Patent Application No. 202422494989.8, filed on October 15, 2024, entitled "Valve Needle Assembly and Electronic Expansion Valve", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of valve technology, and more specifically, to a valve needle assembly and an electronic expansion valve. Background Technology

[0004] Electronic expansion valves are suitable for refrigeration and freezing applications, featuring low internal leakage and precise flow regulation. They can replace combinations of solenoid valves and heating expansion valves. Currently, a seal is typically placed around the valve needle. The valve needle, in conjunction with the valve port, regulates the flow rate, while the seal, in conjunction with the valve port, ensures low internal leakage.

[0005] The existing seal is press-fitted onto the outer wall of the valve needle, and the two are pressed together as a whole into the bushing. Then, the bushing and the tail of the valve needle are laser-welded to form an integral valve needle assembly. Because the laser welding between the bushing and the valve needle causes heat-affected seals, the seals are deformed by heat, which in turn affects the sealing effect.

[0006] Public content

[0007] This disclosure provides a valve needle assembly and an electronic expansion valve, which can reduce deformation of the sealing structure and improve the performance.

[0008] According to a first aspect of this disclosure, a valve needle assembly is provided, comprising:

[0009] The valve needle body includes an adjusting part and a fixing part. The adjusting part is used to selectively block the valve port. Along the axial direction of the adjusting part, one side of the fixing part is connected to the adjusting part, and a fixing groove is provided on the upper end surface of the other side of the fixing part.

[0010] A bushing is fitted over the outside of the valve needle body. Along the axial direction of the adjusting part, a limiting part is provided at one end of the bushing away from the adjusting part. The limiting part is configured to be able to bend along the radial direction of the adjusting part and toward the fixing groove, so that the limiting part is disposed in the fixing groove.

[0011] A sealing structure is sleeved on the outside of the valve needle body and disposed between the valve needle body and the bushing.

[0012] In some embodiments, along the axial direction of the adjusting part, the depth of the fixing groove is C, and the distance between the upper end face of the limiting part and the bottom of the fixing groove is D;

[0013] In this case, C > D.

[0014] In some embodiments, the width of the fixing groove is E along the radial direction of the adjusting part;

[0015] Where 0°≤acos(E / D)<90°.

[0016] In some embodiments, the inner wall of the bushing is provided with a support portion for supporting the sealing structure;

[0017] Along the axial direction of the adjusting part, at least one of the fixing part and the bearing part facing each other is provided with a rib, and the end of the rib facing the sealing structure is embedded in the sealing structure.

[0018] In some embodiments, the cross-section of the rib is a tapered structure, with the smaller end of the tapered structure facing the sealing structure, so that the rib can be embedded inside the rib.

[0019] And / or, the rib is arranged along the circumferential direction of the adjustment part for circumferential limiting of the sealing structure.

[0020] In some embodiments, the rib includes a first limiting portion along the axial direction of the adjusting portion, the first limiting portion being disposed on the side of the fixing portion facing the bearing portion;

[0021] Wherein, along the radial direction of the adjusting part, the distance between the central axis of the first limiting part and the outer wall of the sealing structure is A1, and the thickness of the sealing structure is B1, wherein 0.4B1≤A1≤0.6B1.

[0022] In some embodiments, the rib includes a second limiting portion, which is disposed on the side of the bearing portion facing the fixing portion along the axial direction of the adjusting portion;

[0023] Wherein, along the radial direction of the adjusting part, the distance between the central axis of the second limiting part and the inner sidewall of the bearing part is A2, and the thickness of the bearing part is B2, wherein 0.4B2≤A2≤0.6B2.

[0024] According to a second aspect of this disclosure, an electronic expansion valve is provided, comprising a screw, a valve body, an elastic element, and the aforementioned valve needle assembly, wherein the elastic element is disposed between the screw and the valve needle body, and the valve body is provided with a valve port;

[0025] The screw is configured to drive the valve needle assembly to move along the axial direction of the valve needle assembly, so that the adjusting part of the valve needle assembly selectively seals the valve port.

[0026] In some embodiments, an intermediate component is also included, the intermediate component including a connecting portion and a first positioning portion along the axial direction of the valve needle assembly. The connecting portion is disposed on the side of the screw facing the valve needle assembly, the elastic member abuts against the connecting portion and the fixing portion respectively, and the first positioning portion is disposed on the side of the connecting portion away from the screw and passes through the elastic member.

[0027] It also includes a sleeve, the fixing part is inserted through the sleeve, and the end of the bushing away from the adjusting part is inserted into the sleeve and is interference-fitted with the sleeve, and the elastic element is disposed in the sleeve;

[0028] Along the axial direction of the adjusting part, the outer diameter of the first positioning part is J, the fixing part has a large diameter end and a small diameter end at the end away from the adjusting part, the fixing groove is formed between the large diameter end and the small diameter end, the end face of the small diameter end away from the large diameter end is the upper end face, the outer diameter of the upper end face is F, the outer diameter of the elastic element is G, the inner diameter of the elastic element is g, the wire diameter of the elastic element is d, and the unilateral radial gap between the outer side wall of the connecting part and the inner side wall of the sleeve is k;

[0029] Wherein, G+g+2k-JF<d.

[0030] In some embodiments, the valve needle body further includes a second positioning part along the axial direction of the adjusting part, the second positioning part being disposed on the side of the fixing part away from the adjusting part, and the second positioning part passing through the elastic member.

[0031] In some embodiments, the valve body has a first protrusion and a second protrusion on the side facing the valve needle assembly, and is sleeved with the valve needle assembly, the first protrusion and the second protrusion. The first protrusion is disposed between the valve needle assembly and the second protrusion, the valve port is disposed on the first protrusion, and the second protrusion has a tapered structure, with the small end of the second protrusion facing the fixing part.

[0032] Wherein, the inner diameter of the sealing structure of the valve needle assembly is D1, the outer diameter of the sealing structure of the valve needle assembly is D2, the inner diameter of the valve port is D3, the outer diameter of the first protrusion is D4, and the outer diameter of the second protrusion is D5.

[0033] Where D1≤D3, D4≤D2≤D5.

[0034] One embodiment of this disclosure has the following advantages or beneficial effects:

[0035] The valve needle assembly and electronic expansion valve provided in this embodiment change the fixing method between the fixing part of the valve needle body and the bushing from laser welding to riveting. Riveting does not generate heat, reducing the risk of thermal deformation of the sealing structure and improving the sealing effect of the valve needle assembly, thereby improving the reliability of the sealing structure. Simultaneously, during riveting, the limiting part of the bushing bends radially along the adjusting part and towards the fixing groove, so that the limiting part is positioned within the fixing groove. The fixing groove provides space for the limiting part, ultimately concealing it within the valve needle body. Compared to existing laser welds that can interfere with press-fitting, the connection between the bushing and the valve needle body is neither exposed nor protruding, avoiding the risk of interference during subsequent overall press-fitting of the valve needle assembly or when in contact with other adjacent components. Attached Figure Description

[0036] To better understand this disclosure, reference may be made to the embodiments shown in the following drawings. Components in the drawings are not necessarily to scale, and related elements may be omitted to emphasize and clearly illustrate the technical features of this disclosure. Additionally, related elements or components may have different arrangements as known in the art. Furthermore, in the drawings, the same reference numerals denote the same or similar components in various figures. The above and other features and advantages of this disclosure will become more apparent by describing exemplary embodiments thereof in detail with reference to the drawings.

[0037] in:

[0038] Figure 1 shows a schematic diagram of the structure of a valve needle assembly according to an embodiment of the present disclosure;

[0039] Figure 2 shows a schematic diagram of the structure of an electronic expansion valve according to an embodiment of the present disclosure;

[0040] Figure 3 shows a magnified view of part I in Figure 2.

[0041] The reference numerals in the attached drawings are explained as follows: 1. Valve needle body; 2. Bushing; 3. Sealing structure; 4. Rib; 11. Adjustment part; 111. First section; 112. Second section; 12. Fixing part; 120. Upper end face; 121. Fixing groove; 1221. Groove bottom; 1222. Groove wall; 13. Second positioning part; 21. Limiting part; 22. Bearing part; 31. First sealing part; 32. Second sealing part; 41. First limiting part; 42. Second limiting part; 100. Valve needle assembly; 200. Screw; 300. Valve body; 301. Valve port; 302. First protrusion; 303. Second protrusion; 400. Elastic element; 500. Intermediate part; 501. Connecting part; 502. First positioning part; 600. Sleeve; 700. Bearing. Detailed Implementation

[0042] The technical solutions in the exemplary embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The exemplary embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of this disclosure.

[0043] In the description of this disclosure, unless otherwise expressly specified and limited, the terms “first” and “second” are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term “multiple” refers to two or more; and the term “and / or” includes any and all combinations of one or more associated listed items. In particular, references to “the / described” object or “a” object are also intended to indicate one of a possible plurality of such objects.

[0044] Unless otherwise specified or stated, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0045] Furthermore, it should be understood that the directional terms such as "upper," "lower," "inner," and "outer" described in the exemplary embodiments of this disclosure are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the exemplary embodiments of this disclosure. It should also be understood that, in the context of a reference to an element or feature being connected to another element(s) "upper," "lower," "inner," or "outer," it can be directly connected to the other element(s) "upper," "lower," "inner," or "outer," or indirectly connected to the other element(s) "upper," "lower," "inner," or "outer" through an intermediate element.

[0046] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0047] This embodiment provides a valve needle assembly 100, applicable to the field of control valve technology, particularly electronic expansion valves. As shown in FIG1, the valve needle assembly 100 includes a valve needle body 1, a bushing 2, and a sealing structure 3. The valve needle body 1 includes an adjusting portion 11 and a fixing portion 12. The adjusting portion 11 cooperates with a valve port 301 (as shown in FIG2). Along the axial direction of the adjusting portion 11, the adjusting portion 11 has a first segment 111 and a second segment 112. The second segment 112 is located at the end of the first segment 111 near the valve port 301 and has a tapered section. The adjusting portion 11 is used to selectively block the valve port 301, and the second segment 112 of the adjusting portion 11 is used to adjust the flow rate of the valve port 301. Along the axial direction of the adjusting portion 11, one side of the fixing portion 12 is connected to the adjusting portion 11. The diameter of the adjusting portion 11 is smaller than the diameter of the fixing portion 12, so that the adjusting portion 11 and the fixing portion 12 form a T-shaped structure. The fixing portion 12 is used to install the bushing 2. The bushing 2 is fitted onto the outside of the valve needle body 1, and the sealing structure 3 is fitted onto the outside of the valve needle body 1 and positioned between the valve needle body 1 and the bushing 2 to ensure a sealing effect between the valve needle body 1 and the bushing 2. The sealing structure 3 can be a sealing ring, and the outer shape of the sealing ring can be a cylindrical structure or a similar T-shaped structure, etc.

[0048] During assembly, the sealing structure 3 is first press-fitted onto the outside of the valve needle body 1, that is, the sealing structure 3 is sleeved on the outside of the adjusting part 11 of the valve needle body 1, and the sealing structure 3 abuts against the step between the fixing part 12 and the adjusting part 11, serving as a positioning element. Then, the sealing structure 3 and the valve needle body 1 are pressed into the bushing 2 as a whole. The bushing 2 and the fixing part 12 of the valve needle body 1 can be fixed together by laser welding to ensure that the bushing 2 and the valve needle body 1 form an integral structure.

[0049] If the bushing 2 and the valve needle body 1 are fixed by laser welding, the heat generated by laser welding will cause the sealing structure 3 to deform due to heat, thereby affecting the sealing effect of the sealing structure 3.

[0050] To address this issue, as shown in Figure 1, the valve needle assembly 100 provided in this embodiment has a fixing groove 121 on the upper end face 120 of the fixing part 12 on the other side along the axial direction of the adjusting part 11. Along the axial direction of the adjusting part 11, a limiting part 21 is provided at the end of the bushing 2 away from the adjusting part 11. The limiting part 21 is configured to bend along the radial direction of the adjusting part 11 towards the fixing groove 121, so that the limiting part 21 is disposed within the fixing groove 121. Specifically, the limiting part 21 may be a riveted part.

[0051] During assembly, the sealing structure 3 is pressed onto the outside of the valve needle body 1, and the sealing structure 3 and the valve needle body 1 are pressed into the bushing 2 as a whole. Then, the bushing 2 and the fixing part 12 of the valve needle body 1 are fixed by the limiting part 21 to form an integral valve needle assembly 100.

[0052] The valve needle assembly 100 provided in this embodiment achieves a fixed connection between the fixing part 12 of the valve needle body 1 and the bushing 2 directly through the deformation of the limiting part 21 of the bushing 2, with the limiting part 21 extending into the fixing groove 121 of the fixing part 12. This eliminates the need for laser welding, avoids heat generation, reduces the risk of heat deformation of the sealing structure 3, improves the sealing effect of the valve needle assembly 100, and thus enhances the reliability of the sealing structure 3. Simultaneously, the fixing groove 121 provides a space for the limiting part 21. During riveting, the limiting part 21 of the bushing 2 bends along the radial direction of the adjusting part 11 and towards the fixing groove 121, so that the limiting part 21 is positioned within the fixing groove 121 and ultimately hidden within the valve needle body 1. Compared to existing laser welds that can interfere with press-fitting, since the connection between the bushing 2 and the valve needle body 1 is not exposed or protruding, the risk of interference during subsequent overall press-fitting of the valve needle assembly 100 or contact with other adjacent components can be avoided.

[0053] For example, as shown in FIG1, a fixing groove 121 is provided on the end face of the fixing part 12 away from the adjusting part 11 along the axial direction of the adjusting part 11, and the depth of the fixing groove 121 is C along the axial direction of the adjusting part 11. During processing, the end face of the fixing part 12 away from the adjusting part 11 is recessed in the direction close to the adjusting part 11 to form the fixing groove 121, and the fixing groove 121 extends through the edge of the fixing part 12, so that the tail of the fixing part 12 has a step.

[0054] It is understood that the fixing groove 121 can be arranged along the circumference of the adjusting part 11, and the fixing groove 121 is a ring structure; there may also be multiple fixing grooves 121, which are distributed and spaced apart along the circumference of the adjusting part 11, and multiple limiting parts 21 are correspondingly arranged in the multiple fixing grooves 121.

[0055] For example, along the axial direction of the adjusting part 11, the limiting part 21 is disposed on the side of the bushing 2 away from the adjusting part 11. The limiting part 21 and the bushing 2 can be integrally formed, reducing the number of parts assembly steps. The limiting part 21 is correspondingly disposed to the fixing groove 121. Specifically, after the valve needle body 1 is pressed into the bushing 2, before the limiting part 21 deforms, the distance between the upper end face of the limiting part 21 and the bottom of the fixing groove 121 along the axial direction of the adjusting part 11 is D. During riveting, the limiting part 21 is bent along the radial direction of the adjusting part 11, using the connection position between the fixing groove 121 and the outer peripheral wall of the fixing part 12 as the fulcrum, to achieve the effect of internal riveting.

[0056] Where C > D. That is, the depth of the fixing groove 121 is greater than the distance D between the upper end face of the limiting part 21 and the bottom of the fixing groove 121, or, before the limiting part 21 deforms, its projection on the first reference plane is located inside the projection of the fixing groove 121 on the first reference plane, and the first reference plane is parallel to the axial direction of the adjusting part 11. In this way, after bending, the limiting part 21 can only be confined within the fixing groove 121 and will not cover the upper end face 120 of the fixing part 12 on the side away from the adjusting part 11, thus avoiding interference with other components located on the fixing part 12.

[0057] In one embodiment, the width of the fixing groove 121 along the radial direction of the adjusting part 11 is E, wherein 0°≤acos(E / D)<90°.

[0058] Understandably, by using this method, the width E of the fixing groove 121 is greater than or equal to the distance D between the upper end face of the limiting part 21 and the bottom of the fixing groove 121. The fixing groove 121 can fully accommodate the limiting part 21. After bending, the limiting part 21 will only cover the bottom of the fixing groove 121, or extend to the connection position between the bottom 1221 and the wall 1222 of the fixing groove 121, improving the riveting and fixing effect and ensuring the connection stability between the valve needle assemblies 100 and the bushings 2. Understandably, the limiting part 21 will not extend to the wall 1222 of the fixing groove 121, and it can also avoid the situation where the edge of the limiting part 21 warps due to multiple folds.

[0059] In one embodiment, as shown in FIG1, the inner wall of the bushing 2 is provided with a support portion 22, which is used to support the sealing structure 3 and can provide a certain support force for the sealing structure 3.

[0060] The sealing structure 3 is made of a relatively soft material, such as rubber or other elastic materials, possessing a certain degree of deformation capability and sealing performance. Specifically, the sealing structure 3 includes a first sealing part 31 and a second sealing part 32. The adjusting part 11 of the valve needle body 1 is coaxially inserted through the first sealing part 31 and the second sealing part 32. The outer diameter of the first sealing part 31 is larger than the outer diameter of the second sealing part 32, causing the cross-section of the sealing structure 3 to form a T-shaped structure. The first sealing part 31 is sleeved on the outside of the adjusting part 11 and disposed between the fixing part 12, the bushing 2, and the supporting part 22. The supporting part 22 is used to support the first sealing part 31. The second sealing part 32 is sleeved on the outside of the adjusting part 11 and disposed between the adjusting part 11 and the bushing 2.

[0061] As shown in Figure 1, at least one of the fixing part 12 and the bearing part 22 facing each other along the axial direction of the adjusting part 11 is provided with a rib 4. The end of the rib 4 facing the sealing structure 3 can be embedded in the sealing structure 3. The rib 4 is used for limiting the sealing structure 3.

[0062] For example, the rib 4 may be provided only on the fixing part 12, and the rib 4 protrudes from the end face of the fixing part 12 toward the bearing part 22 toward the bearing part 22 to limit the upper end face of the sealing structure 3 in the axial direction of the adjusting part 11; the rib 4 may also be provided only on the bearing part 22, and the rib protrudes from the end face of the bearing part 22 toward the fixing part 12 toward the fixing part 12 to limit the lower end face of the sealing structure 3 in the axial direction of the adjusting part 11; the rib 4 may also be provided on the fixing part 12 and the bearing part 22 respectively to limit the upper and lower end faces of the sealing structure 3 in the axial direction of the adjusting part 11.

[0063] Additionally, it should be noted that at low temperatures, the shrinkage of the PTFE-made sealing structure 3 along the axial direction of the adjusting part 11 is greater than the shrinkage along the radial direction of the adjusting part 11. When the sealing structure 3 shrinks along the axial direction of the adjusting part 11, the refrigerant may migrate through the gap between the sealing structure 3, the bushing 2, and the valve needle body 1, causing leakage. By setting the rib 4, the rib 4 is equivalent to an additional layer of protection, that is, the rib 4 acts as a waterproof rib, which can achieve the effect of blocking the refrigerant even if axial shrinkage occurs. The cross-section of the rib 4 is a tapered structure, and the small diameter end of the tapered structure is set towards the sealing structure 3, so that the small diameter end of the rib 4 can be embedded in the rib of the sealing structure 3.

[0064] For example, the cross-section of the rib 4 is triangular. After pressing, the rib 4 can be inserted into the interior of the relatively soft sealing structure 3, preventing the sealing structure 3 from shifting. It is understood that the cross-section of the rib 4 can also be other shapes, as long as the end of the rib 4 facing the sealing structure 3 can be embedded in the sealing structure 3, it is within the protection scope of this embodiment.

[0065] The rib 4 is arranged circumferentially along the adjusting part 11, that is, the rib 4 is an annular protrusion, which is used to limit the circumferential movement of the sealing structure 3 to prevent the sealing structure 3 from rotating circumferentially. At the same time, the sealing structure 3 can also ensure the sealing effect of the entire valve needle assembly 100 after thermal expansion and contraction, and prevent the refrigerant from migrating through the gap between the sealing structure 3 and the valve needle body 1 and the bushing 2.

[0066] Specifically, as shown in Figure 1, the protruding rib 4 includes a first limiting part 41, which is disposed on the side of the fixing part 12 facing the bearing part 22 along the axial direction of the adjusting part 11. That is, along the axial direction of the adjusting part 11, the first limiting part 41 protrudes from the lower end face of the fixing part 12. The first limiting part 41 and the fixing part 12 can be integrally formed, reducing the number of parts assembly steps and saving production costs.

[0067] Along the radial direction of the adjusting part 11, the distance between the central axis of the first limiting part 41 and the outer wall of the sealing structure 3 is A1, and the thickness of the sealing structure 3 is B1, wherein 0.4B1≤A1≤0.6B1. For example, A1 can be selected as 0.4B1, 0.5B1, 0.6B1, etc., preferably 0.5B1.

[0068] The contact surface between the fixing part 12 and the sealing structure 3 is the first annular surface. In this way, it is equivalent to the first limiting part 41 being located in the middle of the first annular surface, which improves the fixing balance of the first limiting part 41 on the sealing structure 3. While preventing the sealing structure 3 from rotating circumferentially, it can also further improve the sealing effect between the bushing 2, the sealing structure 3 and the valve needle body 1.

[0069] In one embodiment, the rib 4 includes a second limiting portion 42, which is disposed on the side of the bearing portion 22 facing the fixing portion 12 along the axial direction of the adjusting portion 11. That is, along the axial direction of the adjusting portion 11, the first limiting portion 41 protrudes from the upper end face of the bearing portion 22. The second limiting portion 42 and the bearing portion 22 can be integrally formed, reducing the number of parts assembly steps and saving production costs.

[0070] In this configuration, along the radial direction of the adjusting portion 11, the distance between the central axis of the second limiting portion 42 and the inner wall of the bearing portion 22 is A2, and the thickness of the bearing portion 22 is B2, wherein 0.4B2≤A2≤0.6B2. For example, A2 can be selected from 0.4B2, 0.5B2, 0.6B2, etc., and preferably 0.5B2.

[0071] The contact surface between the bearing part 22 and the sealing structure 3 is the second annular surface. In this way, it is equivalent to the second limiting part 42 being located in the middle of the second annular surface, which improves the fixation balance of the second limiting part 42 on the sealing structure 3. While preventing the sealing structure 3 from rotating circumferentially, it can also further improve the sealing effect between the bushing 2, the sealing structure 3 and the valve needle body 1.

[0072] This embodiment also provides an electronic expansion valve, as shown in Figure 2. The electronic expansion valve includes a screw 200, a valve body 300, an elastic element 400, and the aforementioned valve needle assembly 100. The elastic element 400 may be a cylindrical spring, etc., and is disposed between the screw 200 and the valve needle body 1. The valve body 300 is provided with a valve port 301. The screw 200 is configured to drive the valve needle assembly 100 to move along the axial direction of the valve needle assembly 100, causing the adjusting portion 11 of the valve needle assembly 100 to selectively seal the valve port 301.

[0073] The elastic element 400 is disposed between the screw 200 and the valve needle body 1. When the valve needle assembly 100 opens or closes the valve port 301, the elastic element 400 buffers the movement of the valve needle body 1, ensuring the smooth opening of the valve needle body 1.

[0074] In addition, the axial direction of the valve needle assembly 100 is the same as the axial direction of the adjustment part 11. When the valve needle assembly 100 opens or closes the valve port 301, the lower end of the elastic member 400 abuts against the upper end face of the fixing part 12 of the valve needle body 1.

[0075] It should be noted that, since the riveting dimensions are relatively difficult to control precisely, the limiting part 21 of the bushing 2 is riveted and bent into the fixing groove 121 of the fixing part 12, so that the limiting part 21, as the riveting flange formed after bending, will not interfere with the elastic element 400, reducing the risk of the elastic element 400 getting stuck, thereby improving the reliability of the electronic expansion valve.

[0076] In one embodiment, as shown in Figures 2-3, the valve body 300 has a first protrusion 302 and a second protrusion 303 on the side facing the valve needle assembly 100. The first protrusion 302 is disposed between the valve needle assembly 100 and the second protrusion 303, and the valve port 301 is disposed on the first protrusion 302.

[0077] The first protrusion 302 and the second protrusion 303 form an annular protrusion structure, which is used to abut against the end face of the sealing structure 3 facing the valve port 301, thereby ensuring the sealing effect of the sealing structure 3 on the valve port 301.

[0078] Specifically, the first protrusion 302 has a cylindrical shape. The end face of the sealing structure 3 facing the valve port 301 abuts against the first protrusion 302 to ensure the sealing effect of the valve port 301. The first protrusion 302 is connected to the second protrusion 303, which has a tapered structure. The smaller end of the second protrusion 303 faces the fixing part 12. That is, along the axial direction of the adjusting part 11 and away from the sealing structure 3, the outer diameter of the second protrusion 303 gradually increases. The end face of the sealing structure 3 facing the valve port 301 can at least partially abut against the second protrusion 303, further ensuring the sealing effect while also ensuring the flow regulation accuracy of the valve port 301 to a certain extent.

[0079] In one embodiment, as shown in Figures 2-3, the inner diameter of the sealing structure 3 of the valve needle assembly 100 is D1, where D1 is the inner diameter of the sealing structure 3 assembled onto the valve needle body 1. Specifically, the sealing structure 3 is assembled onto the first segment 111, and the second segment 112 is conical. The inner diameter of the sealing structure 3 matches the outer diameter of the first segment 111 of the adjusting part 11 on the valve needle body 1. The inner diameter of the valve port 301 is D3, where D1 ≤ D3. That is, the inner diameter D3 of the sealing structure 3 is less than or equal to the inner diameter of the valve port 301. This prevents interference between the outer wall of the adjusting part 11 of the valve needle assembly 100 and the valve port 301 when the valve needle assembly 100 closes the valve port 301. The end face of the sealing structure 3 facing the valve port 301 can seal the gap between the adjusting part 11 and the valve port 301, achieving a sealing effect of the sealing structure 3 on the valve port 301.

[0080] In one embodiment, the outer diameter of the sealing structure 3 of the valve needle assembly 100 is D2, the outer diameter of the first protrusion 302 is D4, and the outer diameter of the second protrusion 303 is D5; D4≤D2≤D5. In this manner, when the valve needle assembly 100 closes the valve port 301, the side of the sealing structure 3 facing the valve port 301 away from the center of the adjusting part 11 can deform towards the inclined sidewall of the second protrusion 303, further ensuring the sealing effect.

[0081] In one embodiment, as shown in Figures 2-3, the electronic expansion valve further includes a sleeve 600. The fixing portion 12 of the valve needle body 1 passes through the sleeve 600, and the end of the bushing 2 away from the adjusting portion 11 passes through the sleeve 600 and is interference-fitted with the sleeve 600. The bushing 2 and the sleeve 600 can also be fixed by laser welding. An elastic element 400 is disposed within the sleeve 600, and the sleeve 600 provides installation and movement space for the elastic element 400. The sleeve 600 can also be referred to as a spring sleeve.

[0082] It should be noted that if the fixing part 12 of the valve needle body 1 and the bushing 2 are laser-welded, the weld will protrude beyond the outer edge of the bushing 2 due to the thickness of the laser weld. When the valve needle assembly 100 is press-fitted onto the sleeve 600, this weld will interfere with the inner wall of the sleeve 600, thus affecting the press-fitting between the valve needle assembly 100 and the sleeve 600. However, in this application, the fixing part 12 of the valve needle body 1 and the bushing 2 are fixed together by riveting, avoiding interference when the valve needle assembly 100 is press-fitted onto the sleeve 600.

[0083] In one embodiment, the electronic expansion valve further includes a bearing 700, which is disposed within the sleeve 600 and located at the end of the elastic element 400 away from the valve needle body 1. The outer ring of the bearing 700 is clearance-fitted with the inner circumferential surface of the sleeve 600, and one end of the screw 200 passes through the inner ring of the bearing 700 and is fixedly connected to the inner ring of the bearing 700. This arrangement ensures that the valve needle body 1 performs only linear motion during the opening and closing process, guaranteeing the smoothness of the valve opening and closing process.

[0084] In one embodiment, the electronic expansion valve further includes an intermediate component 500, which is disposed between the bearing 700 and the valve needle body 1. The two ends of the elastic member 400 abut against the intermediate component 500 and the fixing portion 12 of the valve needle body 1, respectively. The intermediate component 500 provides an abutment position for the elastic member 400 and increases the contact area with the elastic member 400. The intermediate component 500 can also be referred to as a gasket.

[0085] Specifically, the intermediate component 500 includes a connecting portion 501. The screw 200 is connected to the connecting portion 501 via a bearing 700. That is, along the axial direction of the valve needle assembly 100, the connecting portion 501 is located on the side of the screw 200 facing the valve needle assembly 100. An elastic element 400 abuts against both the connecting portion 501 and the fixing portion 12. The connecting portion 501 increases the contact area with the elastic element 400, ensuring that all power generated by the screw 200 can be transmitted to the elastic element 400 through the connecting portion 501. The elastic element 400 drives the valve needle assembly 100 to move towards the valve port 301. Additionally, the elastic element 400 also serves to buffer and reset the valve needle assembly 100.

[0086] Specifically, as shown in Figure 3, the intermediate component 500 also includes a first positioning part 502. The first positioning part 502 is disposed on the side of the connecting part 501 away from the screw 200, and the first positioning part 502 passes through the elastic member 400. Along the axial direction of the adjusting part 11, the upper part of the elastic member 400 can be positioned by the first positioning part 502 to avoid large positional displacement of the elastic member 400 during the operation of the electronic expansion valve.

[0087] In one embodiment, along the axial direction of the adjusting part 11, the outer diameter of the first positioning part 502 is J, the outer diameter of the end face of the fixing part 12 away from the adjusting part 11 is F, the outer diameter of the elastic element 400 is G, the inner diameter of the elastic element 400 is g, the wire diameter of the elastic element 400 is d, and the unilateral radial gap between the outer wall of the connecting part 501 and the inner wall of the sleeve 600 is k. Wherein, (G / 2 + (gJ) / 2 + k) - F / 2 < d / 2.

[0088] It is understandable that gJ is the radial clearance between the inner diameter of the elastic element 400 and the first positioning part 502, and (gJ) / 2) is the single-sided radial clearance between the inner diameter of the elastic element 400 and the first positioning part 502. For example, when the elastic element 400 deviates to the right to the limit along the radial direction of the adjusting part 11, the left inner wall of the elastic element 400 contacts the first positioning part 502. Then, the portion of the elastic element 400 to the right along the radial direction of the adjusting part 11 protrudes to the right by an amount of (gJ) / 2, where G / 2 is the initial outer wall radius of the elastic element 400, and k is the radius of the intermediate part 500. The radial clearance on one side between the outer wall of the connecting part 501 and the inner wall of the sleeve 600, assuming that the intermediate part 500 also undergoes radial limit offset during the operation of the electronic expansion valve, and the direction of the radial offset is the same as the direction of the radial limit offset of the elastic part 400, then k is the maximum radial offset dimension of the connecting part 501, and (gJ) / 2+k is the maximum radial protrusion of the outer wall of the elastic part 400 in a certain direction when the elastic part 400 is in the radial limit offset position (that is, when both the intermediate part 500 and the elastic part 400 undergo radial limit offset and the offset direction is the same).

[0089] In one embodiment, both the intermediate member 500 and the elastic member 400 undergo radial limit offset to the right. After the limit offset, the right side portion of the elastic member 400 must be at least partially located on the upper end face 120 of the fixed part 12. That is, the right side portion of the elastic member 400 may detach from the upper end face of the fixed part 12 and be suspended relative to the fixed part 12. (G / 2+(gJ) / 2)-F / 2 is the distance by which the right side portion of the elastic member 400 detaches from the upper end face of the fixed part 12. If this distance is greater than or equal to d, the elastic member 400 will completely detach from the upper end face of the fixed part 12.

[0090] If (G / 2+(gJ) / 2+k)-F / 2≥d / 2, then after the elastic element 400 undergoes radial displacement, it may partially detach from the upper end face of the fixing part 12 and become stuck at the junction of the upper end face of the fixing part 12 and the limiting part 121. Therefore, by setting (G / 2+(gJ) / 2+k)-F / 2<d / 2, even if the elastic element 400 undergoes extreme displacement, it can be ensured that the lower end face of the elastic element 400 effectively abuts against the end face of the fixing part 12 on the side away from the adjusting part 11, preventing the elastic element 400 from tilting and detaching from the end face of the fixing part 12 on the side away from the adjusting part 11. After transforming the formula (G / 2+(gJ) / 2+k)-F / 2<d / 2, we can obtain G+g+2k-JF<d.

[0091] In one embodiment, as shown in FIG3, the valve needle body 1 further includes a second positioning part 13. Along the axial direction of the adjusting part 11, the second positioning part 13 is disposed on the side of the fixing part 12 away from the adjusting part 11, and the second positioning part 13 passes through the elastic member 400. Along the axial direction of the adjusting part 11, the lower part of the elastic member 400 can be positioned by the second positioning part 13 to avoid large positional displacement of the elastic member 400.

[0092] It should be noted that the embodiments disclosed herein are merely one example of the principles employed. Those skilled in the art will clearly understand that the principles of this disclosure are not limited to any details or components of the apparatus shown in the drawings or described in the specification.

[0093] It should be understood that this disclosure is not limited to the detailed structure and arrangement of the components presented in this specification. This disclosure is capable of other embodiments and can be implemented and performed in various ways. The foregoing variations and modifications fall within the scope of this disclosure. It should be understood that this disclosure, as disclosed and defined in this specification, extends to all alternative combinations of two or more individual features mentioned or apparent in the text and / or drawings. All these different combinations constitute multiple alternative aspects of this disclosure. The embodiments described in this specification illustrate the best known mode for implementing this disclosure and will enable those skilled in the art to utilize this disclosure.

[0094] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the inventions disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and exemplary embodiments are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

[0095] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of protection of this disclosure is limited only by the appended claims.

Claims

1. A valve needle assembly, characterized in that include: The valve needle body (1) includes an adjusting part (11) and a fixing part (12). Along the axial direction of the adjusting part (11), one side of the fixing part (12) is connected to the adjusting part (11), and a fixing groove (121) is provided on the upper end face (120) of the other side of the fixing part (12). A bushing (2) is fitted onto the outside of the valve needle body (1). Along the axial direction of the adjusting part (11), a limiting part (21) is provided at one end of the bushing (2) away from the adjusting part (11). The limiting part (21) is configured to be able to bend along the radial direction of the adjusting part (11) and toward the fixing groove (121), so that the limiting part (21) is disposed in the fixing groove (121). A sealing structure (3) is sleeved on the outside of the valve needle body (1) and disposed between the valve needle body (1) and the bushing (2).

2. The valve needle assembly of claim 1, wherein Along the axial direction of the adjusting part (11), the depth of the fixing groove (121) is C, and the distance between the upper end face of the limiting part (21) and the bottom of the fixing groove (121) is D; In this case, C > D.

3. The valve needle assembly of claim 2, wherein, Along the radial direction of the adjustment part (11), the width of the fixing groove (121) is E; Where 0°≤acos(E / D)<90°.

4. The valve needle assembly of claim 1, wherein The inner wall of the bushing (2) is provided with a support part (22), which is used to support the sealing structure (3); Along the axial direction of the adjusting part (11), at least one of the fixing part (12) and the bearing part (22) facing each other is provided with a rib (4), and the end of the rib (4) facing the sealing structure (3) is embedded in the sealing structure (3).

5. The valve needle assembly of claim 4, wherein The cross-section of the rib (4) is a tapered structure, and the small end of the tapered structure is set towards the sealing structure (3) so that the rib (4) can be embedded in the rib (4); And / or, the rib (4) is arranged in the circumferential direction of the adjusting part (11) for circumferential positioning of the sealing structure (3).

6. The valve needle assembly of claim 4, wherein The protruding rib (4) includes a first limiting part (41), which is disposed on the side of the fixing part (12) facing the bearing part (22) along the axial direction of the adjusting part (11). Along the radial direction of the adjusting part (11), the distance between the central axis of the first limiting part (41) and the outer wall of the sealing structure (3) is A1, and the thickness of the sealing structure (3) is B1, wherein 0.4B1≤A1≤0.6B1.

7. The valve needle assembly of claim 4, wherein The rib (4) includes a second limiting part (42), which is disposed on the side of the bearing part (22) facing the fixing part (12) along the axial direction of the adjusting part (11). Along the radial direction of the adjusting part (11), the distance between the central axis of the second limiting part (42) and the inner wall of the bearing part (22) is A2, and the thickness of the bearing part (22) is B2, wherein 0.4B2≤A2≤0.6B2.

8. An electronic expansion valve characterized by It includes a screw (200), a valve body (300), an elastic element (400), and a valve needle assembly as described in any one of claims 1 to 7, wherein the elastic element (400) is disposed between the screw (200) and the valve needle body (1), and the valve body (300) is provided with a valve port (301); The screw (200) is configured to drive the valve needle assembly to move along the axial direction of the valve needle assembly.

9. The electronic expansion valve according to claim 8, wherein It also includes an intermediate component (500), which includes a connecting portion (501) and a first positioning portion (502). Along the axial direction of the valve needle assembly, the connecting portion (501) is disposed on the side of the screw (200) facing the valve needle assembly. The elastic member (400) abuts against the connecting portion (501) and the fixing portion (12) respectively. The first positioning portion (502) is disposed on the side of the connecting portion (501) away from the screw (200). The first positioning portion (502) passes through the elastic member (400). It also includes a sleeve (600), the fixing part (12) passes through the sleeve (600), and the end of the bushing (2) away from the adjusting part (11) passes through the sleeve (600) and is interference-fitted with the sleeve (600), and the elastic element (400) is disposed in the sleeve (600); Along the axial direction of the adjusting part (11), the outer diameter of the first positioning part (502) is J, the fixing part (12) has a large diameter end and a small diameter end at the end away from the adjusting part (11), the fixing groove (121) is formed between the large diameter end and the small diameter end, the end face of the small diameter end away from the large diameter end is the upper end face, the outer diameter of the upper end face is F, the outer diameter of the elastic element (400) is G, the inner diameter of the elastic element (400) is g, the wire diameter of the elastic element (400) is d, and the unilateral radial gap between the outer wall of the connecting part (501) and the inner wall of the sleeve (600) is k. Wherein, G+g+2k-JF<d.

10. The electronic expansion valve according to claim 8, wherein The valve needle body (1) further includes a second positioning part (13). Along the axial direction of the adjusting part (11), the second positioning part (13) is disposed on the side of the fixing part (12) away from the adjusting part (11), and the second positioning part (13) passes through the elastic member (400).

11. The electronic expansion valve according to claim 8, wherein The valve body (300) has a first protrusion (302) and a second protrusion (303) on the side facing the valve needle assembly. The valve needle assembly, the first protrusion (302), and the second protrusion (303) are nested together. The first protrusion (302) is located between the valve needle assembly and the second protrusion (303). The valve port (301) is located on the first protrusion (302). The second protrusion (303) has a tapered structure, and the small end of the second protrusion (303) faces the fixing part (12). Wherein, the inner diameter of the sealing structure (3) of the valve needle assembly is D1, the outer diameter of the sealing structure (3) of the valve needle assembly is D2, the inner diameter of the valve port (301) is D3, the outer diameter of the first protrusion (302) is D4, and the outer diameter of the second protrusion (303) is D5. Where D1≤D3, D4≤D2≤D5.

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