Valve needle structure and electronic expansion valve having the same

Abstract

The utility model discloses a valve needle structure and electronic expansion valve with it, valve needle structure includes: valve needle subassembly, including valve needle body, first limit piece and second limit piece, first limit piece and second limit piece are spaced in the axial direction of valve needle body, and first limit piece is located the one side of second limit piece away from first flow passage inner bottom wall, screw rod subassembly, including screw rod and third limit piece, third limit piece is connected in the one end of screw rod and is located between first limit piece and second limit piece and stretches into first flow passage, elastic component, elastic component is located in first flow passage and is located the one side of screw rod to second limit piece, and elastic component has limit hole on, and second limit piece is arranged in the limit hole, and second limit piece is movable along the axial direction of valve needle body to limit hole. According to the valve needle structure of the utility model, can reduce the friction of valve opening instant, reduce the risk of valve sticking, improve the valve opening performance of electronic expansion valve.

Description

Technical Field

[0001] This utility model relates to the field of refrigerant control element technology, and in particular to a valve needle structure and an electronic expansion valve having the same. Background Technology

[0002] With the rapid development of the automotive industry, automobiles are equipped with an increasing number of devices and functions, making valves, as the medium connecting multiple flow paths, increasingly important in the automobile manufacturing process. In existing technologies, due to considerations regarding the reliability of the valve core's seal on the valve port, a certain amount of friction exists between the valve core and the inner wall of the valve port, leading to valve jamming and affecting the opening performance of the electronic expansion valve. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a valve needle structure that can reduce the frictional force at the moment of valve opening, ensure the normal drive of the screw assembly to the valve needle assembly, reduce the risk of valve jamming, and improve the opening performance of the electronic expansion valve.

[0004] This utility model also proposes an electronic expansion valve, which includes the valve needle structure described above.

[0005] The valve needle structure according to an embodiment of the present invention includes: a valve needle assembly, the valve needle assembly including a valve needle body, a first limiting member and a second limiting member, a first flow channel provided on the axial end face of the valve needle body, the first limiting member and the second limiting member both disposed within the first flow channel, the first limiting member and the second limiting member being spaced apart in the axial direction of the valve needle body, and the first limiting member being located on the side of the second limiting member opposite to the bottom wall of the inner wall of the first flow channel; and a screw assembly, the screw assembly including a screw and a third limiting member, the screw being along the axial direction of the valve needle body. The screw extends into the first limiting member at one end, and the third limiting member is connected to the end of the screw that extends into the first flow channel. Along the axial direction of the valve needle body, the third limiting member is located between the first limiting member and the second limiting member. An elastic component is disposed within the first flow channel and located on the side of the screw facing the second limiting member. The elastic component has a limiting hole, and the second limiting member passes through the limiting hole. The second limiting member is movable relative to the limiting hole along the axial direction of the valve needle body.

[0006] According to the valve needle structure of this utility model embodiment, by providing a limiting hole on the elastic component, the second limiting member of the valve needle assembly passes through the limiting hole, and the second limiting member is movable relative to the limiting hole along the axial direction of the valve needle body. The second limiting member can limit the elastic component, and can prevent the elastic force of the elastic component from acting on the screw assembly when the screw assembly drives the valve needle assembly to open the valve port. This reduces the frictional torque between the third limiting member and the first limiting member, reduces the frictional force at the moment of valve opening, ensures the normal drive of the screw assembly for the valve needle assembly, reduces the risk of valve jamming, improves the valve opening performance of the electronic expansion valve, and relatively reduces the starting current of the electronic expansion valve.

[0007] In addition, the valve needle structure of this utility model may also have the following additional technical features: In some embodiments, the elastic assembly includes an elastic element and a limiting seat arranged along the axial direction of the valve needle body. The limiting seat is located on the side of the elastic element facing the screw. The elastic element is used to drive the limiting seat to move toward the screw. At least a portion of the limiting hole is formed on the limiting seat. When the third limiting element abuts against the first limiting element, the screw assembly is spaced apart from the limiting seat, or the limiting seat is spaced apart from the elastic element.

[0008] In some embodiments, all of the limiting holes are formed on the limiting seat.

[0009] In some embodiments, the limiting seat has a mating hole with an opening on the side of the mating hole facing the elastic member, and at least a portion of the elastic member covers the opening to define the limiting hole.

[0010] In some embodiments, the dimension of the limiting hole in the axial direction of the valve needle body is greater than the outer diameter of the second limiting member.

[0011] In some embodiments, one end of the elastic component along its length abuts against the inner bottom wall of the first flow channel, and the other end is movable along the axial direction of the valve needle body. When the second limiting member abuts against the side wall of the limiting hole away from the screw assembly, the elastic force of the elastic component does not act on the screw assembly.

[0012] In some embodiments, the second limiting member extends radially along the valve needle body, and the cross-section of the second limiting member is an open annular along the extending direction of the second limiting member.

[0013] In some embodiments, the second limiting member includes at least one limiting shaft, one end of which is connected to the inner peripheral wall of the first flow channel, and the other end extends toward the centerline of the valve needle body. The limiting hole includes at least one sub-hole, the limiting shaft is located in the sub-hole, and the sub-hole corresponds one-to-one with the limiting shaft.

[0014] In some embodiments, there are two limiting shafts, which are arranged opposite to each other along the radial direction of the valve needle body and are integral parts.

[0015] The electronic expansion valve according to an embodiment of the present invention includes: a housing having a first cavity, a second cavity, a connecting hole, and a valve port, wherein the first cavity and the second cavity are arranged in the axial direction of the housing, the connecting hole is disposed on the peripheral wall of the first cavity and communicates with the first cavity, and the valve port is disposed at one end of the first cavity opposite to the second cavity; a valve needle structure disposed within the housing, wherein a portion of the valve needle assembly extends into the first cavity for opening or closing the valve port; and a drive assembly disposed on the housing for driving the screw assembly to move along the axial direction of the housing.

[0016] According to the embodiment of the present invention, the electronic expansion valve, by providing the above-mentioned valve needle structure, has a limiting hole on the elastic component, and the second limiting member of the valve needle assembly passes through the limiting hole. The second limiting member is movable relative to the limiting hole along the axial direction of the valve needle body. The second limiting member can limit the elastic component, and can prevent the elastic force of the elastic component from acting on the screw assembly when the screw assembly drives the valve needle assembly to open the valve port. This reduces the frictional torque between the third limiting member and the first limiting member, reduces the frictional force at the moment of valve opening, ensures the normal drive of the screw assembly for the valve needle assembly, reduces the risk of valve jamming, improves the valve opening performance of the electronic expansion valve, and relatively reduces the starting current of the electronic expansion valve.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a perspective view of an electronic expansion valve according to an embodiment of the present utility model; Figure 2 This is a cross-sectional view of the electronic expansion valve according to the first embodiment of the present invention; Figure 3This is a perspective view of the valve needle structure according to the first embodiment of the present utility model; Figure 4 This is a cross-sectional view of the valve needle structure according to the first embodiment of the present invention from one angle; Figure 5 This is a cross-sectional view of the valve needle structure according to the first embodiment of the present invention from another angle; Figure 6 This is a perspective view of the valve needle structure according to the first embodiment of the present utility model, wherein the valve needle body is not shown; Figure 7 This is a cross-sectional view of the electronic expansion valve according to the second embodiment of the present invention; Figure 8 This is a cross-sectional view of the valve needle structure according to the second embodiment of the present utility model; Figure 9 This is a perspective view of the valve needle structure according to the second embodiment of the present utility model, wherein the valve needle body is not shown.

[0019] Figure label: 100. Electronic expansion valve; 1. Valve needle structure; 11. Valve needle assembly; 111. Valve needle body; 112. First limiting member; 113. Second limiting member; 114. First flow channel; 115. Second flow channel; 116. Mounting hole; 12. Screw assembly; 121. Screw; 122. Third limiting member; 13. Elastic component; 130. Limiting hole; 131. Elastic component; 132. Limiting seat; 1321. First surface; 2. Housing; 21. First cavity; 22. Second cavity; 23. Connecting hole; 24. Valve port; 3. Drive assembly; 31. Rotor assembly; 32. Guide component; 33. Nut. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0024] The valve needle structure 1 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0025] like Figure 4 As shown, the valve needle structure 1 according to an embodiment of the present utility model includes a valve needle assembly 11, a screw assembly 12, and an elastic assembly 13.

[0026] Specifically, see the attached document. Figure 3 As shown, the valve needle assembly 11 includes a valve needle body 111, a first limiting member 112, and a second limiting member 113. The valve needle moves along the a direction (e.g., ...). Figure 4 (As shown) Extending outwards, a first flow channel 114 is provided on the axial end face of the valve needle body 111. A first limiting member 112 and a second limiting member 113 are both disposed within the first flow channel 114. The first limiting member 112 extends in a ring shape along the circumferential direction of the valve needle body 111. The first limiting member 112 and the second limiting member 113 extend in the axial direction of the valve needle body 111 (see attached diagram). Figure 4The first limiting member 112 is located on the side of the second limiting member 113 away from the bottom wall of the first flow channel 114, and is spaced apart in the direction a shown.

[0027] Further, see Appendix Figure 4 and attached Figure 5 As shown, the screw assembly 12 includes a screw 121 and a third limiting member 122. The screw 121 extends along the axial direction of the valve needle body 111. The extension direction of the screw 121 is shown in the attached figure. Figure 2 One end of the valve needle 121 (in the direction shown in a) is inserted into the first limiting member 112, and the third limiting member 122 is connected to the end of the screw 121 that extends into the first flow channel 114. Along the axial direction of the valve needle body 111, the third limiting member 122 is located between the first limiting member 112 and the second limiting member 113.

[0028] Furthermore, see the attached document. Figure 4 and attached Figure 5 As shown, the elastic component 13 is disposed in the first flow channel 114 and located on the side of the screw 121 facing the second limiting member 113. The elastic component 13 has a limiting hole 130. The second limiting member 113 passes through the limiting hole 130 and is movable relative to the limiting hole 130 along the axial direction of the valve needle body 111.

[0029] It is understandable that the valve needle structure 1 of this utility model is applied to the electronic expansion valve 100. In related technologies, after the valve core closes the valve port, there is a self-locking friction between the valve core and the valve port to ensure the valve core seals the valve port. The spring is compressed and acts on the screw. At the moment of switching from valve closing to valve opening, the screw contacts the limit ring and rotates relative to it to pull the valve core upward. At this time, the axial force between the screw and the limit ring is the sum of the spring force and the self-locking friction between the valve core and the valve port. Because the friction is too large, the screw may not be able to rotate normally, which will cause the rotor to not be able to rotate normally, affecting the normal opening of the valve port, causing valve jamming, and reducing the opening performance of the electronic expansion valve.

[0030] This invention provides a limiting hole 130 on the elastic component 13, and the second limiting member 113 of the valve needle assembly 11 passes through the limiting hole 130. The second limiting member 113 is movable relative to the limiting hole 130 along the axial direction of the valve needle body 111. The second limiting member 113 can limit the elastic component 13, and prevent the elastic force of the elastic component 13 from acting on the screw assembly 12 when the screw assembly 12 drives the valve needle assembly 11 to open the valve port 24. This reduces the frictional torque between the third limiting member 122 and the first limiting member 112, reduces the frictional force at the moment of valve opening, ensures the normal drive of the screw assembly 12 for the valve needle assembly 11, reduces the risk of valve jamming, improves the valve opening performance of the electronic expansion valve 100, and relatively reduces the starting current of the electronic expansion valve 100.

[0031] Understandably, as the valve needle structure 1 gradually closes the valve port 24, the screw assembly 12 rotates, causing the valve needle assembly 11 and the elastic assembly 13 to move together toward the valve port 24 until the valve needle body 111 blocks the valve port 24. The valve needle assembly 11 can no longer move toward the direction away from the screw 121, and the screw assembly 12 continues to rotate, compressing the elastic assembly 13. The second limiting member 113 is separated from the inner wall of the limiting hole 130 on the side away from the screw assembly 12, generating a pre-tightening force and reserving a set valve opening pulse, so that the electronic expansion valve 100 can have sufficient sealing force to block the valve port 24 when the power is off or when it is not running, thus preventing medium leakage.

[0032] As the valve needle structure 1 gradually opens the valve port 24, the screw assembly 12 rotates, the elastic component 13 gradually resets, and the second limiting member 113 moves relative to the end of the limiting hole 130 away from the screw assembly 12. Then the screw assembly 12 continues to move in the direction away from the valve port 24, and the third limiting member 122 slowly separates from the limiting seat 132 until the third limiting member 122 abuts against the first limiting member 112. The screw assembly 12 drives the valve needle body 111 to move in the direction away from the valve port 24, slowly opening the valve port 24.

[0033] Wherein, the second limiting member 113 is movable relative to the limiting hole 130 along the axial direction of the valve needle body 111. In fact, one end of the elastic component 13 away from the inner bottom wall of the first flow channel 114 moves along the axial direction of the valve needle body 111, so that the limiting hole 130 moves in the axial direction of the valve needle body 111, while the second limiting member 113 does not move relative to the valve needle body 111 in the axial direction; or, the second limiting member 113 can move along the axial direction of the valve needle body 111, but the distance that the limiting hole 130 can move in the axial direction of the valve needle body 111 is greater than the distance that the second limiting member 113 can move in the axial direction of the valve needle body 111.

[0034] It should be noted that the limiting hole 130 can be a circular hole with a diameter larger than the outer diameter of the second limiting member 113, or the limiting hole 130 can be an elongated hole that extends along the axial direction of the valve needle body 111 and has a dimension in the axial direction of the valve needle body 111 that is larger than the outer diameter of the second limiting member 113.

[0035] It should be noted that a flow channel groove is provided on the axial end face of the valve needle body 111. Regarding the definition of the inner bottom wall of the first flow channel 114, it can be that the flow channel groove is directly formed as the first flow channel 114, in which case the inner bottom wall of the first flow channel 114 refers to the inner bottom wall of the flow channel groove. Alternatively, a limiting protrusion is provided in the flow channel groove, and the limiting protrusion extends in a ring shape along the circumferential direction of the flow channel groove. The part of the flow channel groove located on the side of the limiting protrusion away from the inner bottom wall of the flow channel groove forms the first flow channel 114, in which case the inner bottom wall of the first flow channel 114 refers to the surface of the limiting protrusion away from the inner bottom wall of the flow channel groove.

[0036] According to the valve needle structure 1 of this utility model embodiment, by providing a limiting hole 130 on the elastic component 13, the second limiting member 113 of the valve needle assembly 11 passes through the limiting hole 130, and the second limiting member 113 is movable relative to the limiting hole 130 along the axial direction of the valve needle body 111. The second limiting member 113 can limit the elastic component 13, and can prevent the elastic force of the elastic component 13 from acting on the screw assembly 12 during the process of the screw assembly 12 driving the valve needle assembly 11 to open the valve port 24. This reduces the frictional torque between the third limiting member 122 and the first limiting member 112, reduces the frictional force at the moment of valve opening, ensures the normal drive of the screw assembly 12 for the valve needle assembly 11, reduces the risk of valve jamming, improves the valve opening performance of the electronic expansion valve 100, and relatively reduces the starting current of the electronic expansion valve 100.

[0037] In some embodiments of this utility model, reference is made to the appendix. Figure 4 Appendix Figure 5 and attached Figure 8 As shown, the elastic component 13 includes an elastic element 131 and a limiting seat 132 arranged along the axial direction of the valve needle body 111. The length direction of the elastic element 131 (see attached diagram) Figure 4 (Direction a) shown is the axial direction of the valve needle body 111. The end of the elastic element 131 facing away from the screw 121 abuts against the inner bottom wall of the first flow channel 114. The limiting seat 132 is located on the side of the elastic element 131 facing the screw 121 and abuts against the elastic element 131. The elastic element 131 is used to drive the limiting seat 132 to move toward the screw 121. At least a portion of the limiting hole 130 is formed on the limiting seat 132. When the third limiting element 122 abuts against the first limiting element 112, the screw assembly 12 is spaced apart from the limiting seat 132, or the limiting seat 132 is spaced apart from the elastic element 131. This can realize a flexible connection between the screw assembly 12 and the valve needle assembly 11. Compared with the direct fixed connection between the screw and the valve core, the setting of the elastic element 131 can directly abut the limiting seat 132 against the screw 121, eliminate gaps, avoid tolerances, and make the screw 121 more free.

[0038] It should be noted that the valve needle structure 1 of this utility model is basically as follows: Figure 4In the vertical configuration shown, in some cases, if the valve needle structure 1 is used horizontally, as the valve needle structure 1 gradually opens the valve port 24, after the elastic element 131 resets, there may be a situation where the limiting seat 132 is spaced apart from the elastic element 131 but abuts against the third limiting element 122. However, in this case, the elastic force of the elastic element 131 can still be prevented from acting on the screw assembly 12, reducing the frictional torque between the third limiting element 122 and the first limiting element 112, reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 for the valve needle assembly 11, reducing the risk of valve jamming, improving the valve opening performance of the electronic expansion valve 100, and relatively reducing the starting current of the electronic expansion valve 100.

[0039] In a further embodiment of this utility model, reference is made to the appendix. Figure 4 Appendix Figure 5 and attached Figure 6 As shown, all the limiting holes 130 are formed on the limiting seat 132. The design is simple and the limiting seat 132 can be directly limited by the second limiting member 113, which prevents the limiting seat 132 from continuing to move towards the screw 121 under the drive of the elastic member 131. This ensures the effectiveness of the second limiting member 113 in limiting the elastic member 13, further preventing the elastic force of the elastic member 13 from acting on the screw assembly 12, reducing the frictional torque between the third limiting member 122 and the first limiting member 112, reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 on the valve needle assembly 11, reducing the risk of valve jamming, improving the valve opening performance of the electronic expansion valve 100, and relatively reducing the starting current of the electronic expansion valve 100.

[0040] It should be noted that when the third limiting member 122 abuts against the first limiting member 112, the screw assembly 12 and the elastic component 13 are separated. At this time, the second limiting member 113 abuts against the inner wall of the limiting hole 130 on the side opposite to the screw 121.

[0041] In a further embodiment of this utility model, reference is made to the appendix. Figure 8 and attached Figure 9 As shown, the limiting seat 132 has a mating hole, and the side of the mating hole facing the elastic member 131 has an open opening. At least part of the elastic member 131 covers the open opening to define the limiting hole 130. It can be understood that during the assembly process of the valve needle structure 1, the elastic member 131 can be first assembled into the first flow channel 114, then the second limiting member 113 can be fixed to the valve needle body 111, and then the limiting seat 132 and the screw 121 can be placed into the first flow channel 114 in sequence. Finally, the first limiting member 112 can be sleeved on the screw 121 and fixed to the inner wall of the first flow channel 114. This can relatively reduce the difficulty of mating the second limiting member 113 with the elastic component 13, reduce the overall assembly difficulty of the valve needle structure 1, and improve the assembly efficiency of the valve needle structure 1.

[0042] It should be noted that when the third limiting member 122 abuts against the first limiting member 112, the screw assembly 12 and the elastic assembly 13 are separated. At this time, the second limiting member 113 abuts against the end of the elastic member 131 that is away from the bottom wall of the first flow channel 114.

[0043] In a further embodiment of this utility model, reference is made to the appendix. Figure 4 Appendix Figure 5 and attached Figure 9 As shown, the side surface of the limiting seat 132 facing away from the elastic member 131 is the first surface 1321. At least part of the first surface 1321 is formed as a spherical crown protruding towards the side facing away from the elastic member 131. The spherical crown refers to the curved surface remaining after a sphere is cut by a plane. When the first surface 1321 abuts against the screw assembly 12, the top of the first surface 1321 can adjust the contact mode by itself. The top of the first surface 1321 will automatically tend towards the center point of the contact surface, forming a "self-centering" effect. This helps to maintain the perpendicularity of the elastic member 13, reduce lateral friction, prevent the limiting seat 132 from jamming, and protect the limiting seat 132 and the screw assembly 12.

[0044] In some embodiments of this utility model, reference is made to the appendix. Figure 4 Appendix Figure 5 and attached Figure 8 As shown, the dimension of the limiting hole 130 in the axial direction of the valve needle body 111 is larger than the outer diameter of the second limiting member 113, so that the second limiting member 113 can move relative to the valve needle body 111 in the axial direction within the limiting hole 130, and can limit the elastic component 13 through the cooperation between the second limiting member 113 and the limiting hole 130.

[0045] In a further embodiment of this utility model, reference is made to the appendix. Figure 4 Appendix Figure 5 and attached Figure 8 As shown, the length direction of the elastic component 13 (see attached diagram) Figure 4 One end of the valve needle assembly 111 (in the direction shown in a) is abutted against the inner bottom wall of the first flow channel 114, and the other end is movable along the axial direction of the valve needle body 111. When the second limiting member 113 abuts against the side wall of the limiting hole 130 away from the screw assembly 12, the elastic force of the elastic component 13 does not act on the screw assembly 12, which can reduce the frictional torque between the third limiting member 122 and the first limiting member 112, reduce the frictional force at the moment of valve opening, ensure the normal drive of the screw assembly 12 for the valve needle assembly 11, reduce the risk of valve jamming, improve the valve opening performance of the electronic expansion valve 100, and relatively reduce the starting current of the electronic expansion valve 100.

[0046] In some embodiments of this utility model, reference is made to the appendix. Figure 5 Appendix Figure 6 and attachedFigure 9 As shown, the second limiting member 113 extends radially along the valve needle body 111. Along the extending direction of the second limiting member 113, its cross-section is an open annular shape. This open annular shape allows the second limiting member 113 to have elastic deformation capability, enabling it to expand and contract in the circumferential direction. This facilitates the assembly of the second limiting member 113 with the valve needle body 111 and the engagement of the second limiting member 113 with the limiting hole 130. It should be noted that an open annular shape refers to a not fully closed annular structure.

[0047] In a specific example, see Appendix Figure 4 As shown, the outer peripheral wall of the valve needle body 111 has two mounting holes 116. The two mounting holes 116 are arranged opposite each other in the radial direction of the valve needle body 111, and both mounting holes 116 are connected to the first flow channel 114. The second limiting member 113 is simultaneously inserted into the two mounting holes 116 and extends along the arrangement direction of the two mounting holes 116. During the process of assembling the second limiting member 113 onto the valve needle body 111 and the limiting seat 132, the second limiting member 113 needs to be positioned opposite to the two mounting holes 116 and the limiting hole 130. Then, the second limiting member 113 is compressed to reduce its outer diameter, allowing it to be inserted into the first mounting hole 116. The second limiting member 113 is then moved toward the second mounting hole 116 until it passes through the limiting hole 130 and the second mounting hole 116 in sequence. The second elastic member 131 is then restored, allowing the outer diameter of the second limiting member 113 to return to its original position. This achieves an interference fit between the second limiting member 113 and the inner wall of the mounting hole 116, and a limiting fit between the second limiting member 113 and the inner wall of the limiting hole 130, ensuring that the second limiting member 113 can move relative to the limiting hole 130 along the axial direction of the valve needle body 111.

[0048] In some embodiments of this utility model, the second limiting member 113 includes at least one limiting shaft. One end of the limiting shaft is connected to the inner peripheral wall of the first flow channel 114, and the other end extends toward the centerline of the valve needle body 111. The limiting hole 130 includes at least one sub-hole, and the limiting shaft is located in the sub-hole. The sub-holes correspond one-to-one with the limiting shaft. Through the cooperation of the limiting shaft and the sub-hole, the second limiting member 113 can limit the elastic component 13, preventing the end of the elastic component 13 away from the inner bottom wall of the first flow channel 114 from being too far from the first limiting member. When components 112 are too close together, during the process of the screw assembly 12 driving the valve needle assembly 11 to open the valve port 24, the screw assembly 12 and the elastic component 13 are separated, preventing the elastic force of the elastic component 13 from acting on the screw assembly 12, reducing the frictional torque between the third limiting component 122 and the first limiting component 112, reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 for the valve needle assembly 11, reducing the risk of valve jamming, improving the valve opening performance of the electronic expansion valve 100, and relatively reducing the starting current of the electronic expansion valve 100.

[0049] For example, there can be one limiting shaft and one sub-hole corresponding to the limiting shaft; there can be two limiting shafts, with the two limiting shafts arranged opposite each other along the radial direction of the valve needle body 111, and two sub-holes corresponding to the limiting shafts; there can be three limiting shafts, with the three limiting shafts evenly spaced in the circumferential direction of the valve needle body 111, and three sub-holes corresponding to the limiting shafts; there can be four limiting shafts, with the four limiting shafts evenly spaced in the circumferential direction of the valve needle body 111, and four sub-holes corresponding to the limiting shafts.

[0050] In a further embodiment of this utility model, there are two limiting shafts. The two limiting shafts are arranged opposite to each other along the radial direction of the valve needle body 111 and are integral parts. The two limiting shafts are formed as pins. There are two sub-holes that correspond one-to-one with the two limiting shafts. The two sub-holes are arranged opposite to each other and connected in the radial direction of the valve needle body 111, so that the limiting hole 130 passes through the limiting seat 132 along the radial direction of the limiting seat 132. The pin passes through the limiting hole 130. In this way, while ensuring the force balance between the limiting seat 132 and the valve needle body 111, the number of parts of the second limiting member 113 can be reduced as much as possible, reducing the assembly difficulty of the valve needle structure 1 and facilitating the assembly of the valve needle structure 1.

[0051] In some embodiments of this utility model, the first limiting member 112 extends in a ring shape along the circumferential direction of the valve needle body 111, and the third limiting member 122 includes a plurality of rolling members, the axial direction of which is perpendicular to the extension direction of the screw 121 (see attached figure). Figure 4As shown in direction a), multiple rolling elements are spaced apart in the circumferential direction of the screw 121. The outer peripheral wall of the rolling elements is adapted to roll contact with the end face of the first limiting member 112 facing the second limiting member 113. The rolling elements can convert the sliding friction between the first limiting member 112 and the third limiting member 122 into rolling friction, which can further reduce the frictional torque, reduce the frictional force at the moment of valve opening, ensure the normal drive of the screw assembly 12 for the valve needle assembly 11, reduce the risk of valve jamming, improve the valve opening performance of the electronic expansion valve 100, and relatively reduce the starting current of the electronic expansion valve 100. The multiple rolling elements can increase the rolling contact points between the screw 121 and the first limiting member 112, ensure the force balance between the first limiting member 112 and the screw assembly 12, and ensure the reliability and stability of the valve needle structure 1. For example, the number of rolling elements can be two, three, four, or five.

[0052] In a further embodiment of this utility model, the screw 121 includes a rod body and a pin. The rod body extends along the axial direction of the valve needle body 111. One end of the rod body extending in the direction of extension passes through the first limiting member 112. The pin is connected to one end of the rod body that extends into the first flow channel 114 and passes through the rod body. The pin is interference-fitted with the rod body. The axial direction of the pin is perpendicular to the extension direction of the rod body. Both ends of the pin extend beyond the rod body. There are two rolling elements. The two rolling elements are respectively sleeved on the axial ends of the pin. The pin is set to install the rolling elements, which facilitates the connection of the rolling elements to the rod body. This ensures that the rod body can drive the rolling elements to rotate together in the circumferential direction of the rod body, thereby ensuring rolling contact between the rolling elements and the first limiting member 112. The two rolling elements respectively sleeved on the axial ends of the pin can minimize the number of parts of the screw assembly 12 while ensuring the force balance between the first limiting member 112 and the screw assembly 12, thereby reducing the assembly difficulty of the valve needle structure 1 and facilitating the assembly of the valve needle structure 1.

[0053] In a further embodiment of this utility model, the rolling element is a bushing, which is clearance-fitted with the pin. The bushing is rotatable relative to the pin. On the one hand, the bushing has a simple structure and low price, which can reduce the production cost of the screw assembly 12 and thus reduce the total cost of the valve needle structure 1. On the other hand, the bushing is simple and quick to assemble, and can be directly sleeved on both ends of the pin, which can reduce the assembly difficulty of the screw assembly 12, shorten the assembly time of the valve needle structure 1, and save the assembly cost of the valve needle structure 1.

[0054] Alternatively, the rolling element can be a bearing, with the inner ring of the bearing fixedly connected to the pin. The outer ring of the bearing is adapted to roll contact with the end face of the first limiting member 112 facing the second limiting member 113. Through the interference fit between the inner ring of the bearing and the pin, the outer ring of the bearing can rotate relative to the pin. This ensures that the outer peripheral wall of the rolling element is in rolling contact with the first limiting member 112, while making the connection between the rolling element and the pin more reliable. It also prevents the rolling element from coming off the pin after assembly, ensuring the reliability and stability of the screw assembly 12 and improving the reliability of the valve needle structure 1.

[0055] It should be noted that since the bearing and the pin are relatively fixed in the length direction of the pin, the bearing can be prevented from coming off the pin, thereby preventing the bearing from contacting the inner circumferential wall of the first flow channel 114, reducing the possibility of friction between the bearing and the inner wall of the first flow channel 114, relatively reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 to the valve needle body 111, reducing the risk of valve jamming, and improving the valve opening performance of the electronic expansion valve 100.

[0056] This utility model also proposes an electronic expansion valve 100 having the valve needle structure 1 of the above embodiments.

[0057] like Figure 2 and attached Figure 7 As shown, the electronic expansion valve 100 according to an embodiment of the present invention includes a housing 2, the valve needle structure 1 described above, and a drive assembly 3.

[0058] Specifically, see the attached document. Figure 1 As shown, the housing 2 protects the internal structure of the electronic expansion valve 100, which helps extend the service life of the electronic expansion valve 100. The housing 2 has a first cavity 21, a second cavity 22, a connecting hole 23, and a valve port 24. The first cavity 21 and the second cavity 22 are in the axial direction of the housing 2 (see attached diagram). Figure 2 Arranged in the direction shown (a), the connecting hole 23 is located on the peripheral wall of the first cavity 21 and communicates with the first cavity 21, and the valve port 24 is located at the end of the first cavity 21 opposite to the second cavity 22. The medium can flow into the first cavity 21 through one of the connecting hole 23 and the valve port 24, and flow out through the other of the connecting hole 23 and the valve port 24. For example, the medium can be refrigerant.

[0059] Further, see attached document. Figure 2As shown, the valve needle structure 1 is located inside the housing 2, and part of the valve needle assembly 11 extends into the first cavity 21 to open or close the valve port 24. The axial direction of the valve needle body 111 is the same as the axial direction of the housing 2. When the valve needle body 111 closes the valve port 24, the connecting hole 23 and the valve port 24 are no longer connected, and the medium cannot flow from the valve port 24 into the first cavity 21, nor can the medium in the first cavity 21 flow out from the valve port 24. The drive assembly 3 is located on the housing 2 and is used to drive the screw assembly 12 to move along the axial direction of the housing 2.

[0060] Under the drive of the drive assembly 3, the screw 121 drives the valve needle assembly 11 to move along the axial direction of the housing 2. When the valve needle body 111 opens the valve port 24, the medium can flow into the first cavity 21 from one of the valve port 24 and the connecting hole 23, and then flow from the first cavity 21 to the other of the valve port 24 and the connecting hole 23. When the valve needle body 111 closes the valve port 24, the medium in the first cavity 21 cannot flow out from the valve port 24, and the medium outside the electronic expansion valve 100 cannot flow into the first cavity 21 from the valve port 24. By opening or closing the valve port 24, different user needs can be met and the user experience can be improved.

[0061] Further, see attached document. Figure 2 and attached Figure 7 As shown, the drive assembly 3 includes a coil component, a rotor component 31, a guide 32, and a nut 33. The coil component is sleeved outside the housing 2, and the rotor component 31 is disposed inside the housing 2. The coil component is located radially outside the rotor component 31 and is disposed opposite to at least a portion of the rotor component 31, for driving the rotor component 31 to rotate. The guide 32 is fixed inside the rotor component 31, and the nut 33 is fixed inside the housing 2. The screw 121 passes through the nut 33 and the guide 32 and extends along its length (see attached diagram). Figure 2 One end of the rotor (in direction a) is welded to the guide 32, so that the rotor component 31, the guide 32 and the screw 121 rotate synchronously. Part of the screw 121 is threadedly connected to the nut 33. Since the screw 121 and the nut 33 are threadedly engaged to form a threaded pair, and the nut 33 is fixed inside the housing 2, the screw 121 needs to move along the axial direction of the housing 2 while rotating. The guide 32 and the rotor component 31 move along the axial direction of the housing 2 together with the screw 121.

[0062] It is understandable that, such as Figure 2As shown, when the coil component is energized, it drives the rotor component 31 to rotate. Since the screw 121 is fixedly connected to the rotor component 31 through the guide 32, the rotor component 31 drives the screw 121 to rotate together. The screw 121 and the nut 33 are threaded together to form a threaded pair. The nut 33 is fixed on the housing 2, so that the screw 121 moves along the axial direction of the housing 2, thereby driving the rotor component 31 to move along the axial direction of the housing 2. During the process of the rotor component 31 moving along the axial direction of the housing 2, at least a part of the rotor component 31 is opposite to the coil component to ensure that the coil component drives the rotor component 31 to rotate normally.

[0063] According to the embodiment of the present invention, the electronic expansion valve 100, by providing the above-mentioned valve needle structure 1, and by providing a limiting hole 130 on the elastic component 13, the second limiting member 113 of the valve needle assembly 11 passes through the limiting hole 130, and the second limiting member 113 is movable relative to the limiting hole 130 along the axial direction of the valve needle body 111. The second limiting member 113 can limit the elastic component 13, and during the process of the screw assembly 12 driving the valve needle assembly 11 to open the valve port 24, the elastic force of the elastic component 13 is prevented from acting on the screw assembly 12, reducing the frictional torque between the third limiting member 122 and the first limiting member 112, reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 to the valve needle assembly 11, reducing the risk of valve jamming, improving the valve opening performance of the electronic expansion valve 100, and relatively reducing the starting current of the electronic expansion valve 100.

[0064] In some embodiments of this utility model, reference is made to the appendix. Figure 2 As shown, the valve needle body 111 is also provided with a second flow channel 115. One end of the second flow channel 115 along the axial direction of the valve needle body 111 is connected to the first flow channel 114, and the other end is connected to the valve port 24. The inner diameter of the second flow channel 115 is smaller than the inner diameter of the first flow channel 114. The end of the elastic component 13 that is away from the screw 121 is stopped by the stepped surface between the first flow channel 114 and the second flow channel 115.

[0065] It is understandable that the medium can flow into the second flow channel 115 from the valve port 24 and flow along the second flow channel 115 to the first flow channel 114. Finally, the second cavity 22 of the first flow channel 114 can keep the air pressure in the second cavity 22 consistent with the air pressure on the side of the valve needle body 111 away from the second cavity 22, ensuring that the valve needle assembly 11 is always in a pressure balance state during the switching process, and avoiding affecting the normal movement of the valve needle assembly 11 along the axial direction of the housing 2.

[0066] Understandably, during the gradual closing process of the electronic expansion valve 100: the screw assembly 12 moves towards the valve port 24, and the screw 121 abuts against the end of the limiting seat 132 away from the elastic element 131. Since the elastic element 131 is relatively rigid, it is not compressed at this time, causing the valve needle body 111, the limiting seat 132, and the elastic element 131 to move together as a whole towards the valve port 24 until the valve needle body 111 blocks the valve port 24. 1. It cannot continue to move, but under the drive of the drive component 3, the screw 121 continues to rotate and move toward the direction close to the valve port 24, slowly pushing the limit seat 132 toward the direction close to the elastic member 131. The second limit member 113 moves relative to the end of the limit hole 130 away from the elastic member 131, compressing the elastic member 131, generating a pre-tightening force, and reserving a set valve opening pulse, so that the electronic expansion valve 100 can have sufficient sealing force to seal the valve port 24 when the power is off or when it is not running, to avoid medium leakage.

[0067] The process of the electronic expansion valve 100 gradually opening: the screw assembly 12 moves away from the valve port 24, the elastic element 131 gradually resets, and then the screw assembly 12 continues to move away from the valve port 24 until the third limiting element 122 abuts against the first limiting element 112, the third limiting element 122 is spaced apart from the limiting seat 132, the screw assembly 12 drives the valve needle body 111 to move away from the valve port 24, and the valve port 24 opens. At this time, the medium can flow into the first cavity 21 through one of the connecting hole 23 and the valve port 24, and flow out through the other, thereby ensuring the reliability and stability of the valve needle body 111 sealing the valve port 24, reducing the failure risk of the electronic expansion valve 100, and extending the service life of the electronic expansion valve 100.

[0068] It should be noted that during the process of the valve needle body 111 blocking the valve port 24 and the screw 121 continuing to move toward the valve port 24, the second limiting member 113 moves within the limiting hole 130 and moves relative to the end of the limiting hole 130 away from the elastic member 131. However, the second limiting member 113 is spaced apart from the side wall of the limiting hole 130 away from the elastic member 131, so as to avoid the screw 121 directly applying force to the second limiting member 113 and the valve needle body 111, to avoid the screw 121 applying too much force to the valve needle assembly 11, to avoid the excessive squeezing force between the valve needle body 111 and the valve port 24, and to avoid wear at the valve needle body 111 and the valve port 24. This can relatively extend the service life of the electronic expansion valve 100 and ensure the sealing reliability of the valve port 24 of the electronic expansion valve 100.

[0069] Other configurations and operations of the valve needle structure 1 and the electronic expansion valve 100 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0070] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0071] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A valve needle structure, characterized in that, include: A valve needle assembly (11) includes a valve needle body (111), a first limiting member (112), and a second limiting member (113). A first flow channel (114) is provided on the axial end face of the valve needle body (111). The first limiting member (112) and the second limiting member (113) are both provided in the first flow channel (114). The first limiting member (112) and the second limiting member (113) are spaced apart in the axial direction of the valve needle body (111), and the first limiting member (112) is located on the side of the second limiting member (113) away from the bottom wall of the first flow channel (114). A screw assembly (12) includes a screw (121) and a third limiting member (122). The screw (121) extends along the axial direction of the valve needle body (111). One end of the screw (121) extending along the axial direction passes through the first limiting member (112). The third limiting member (122) is connected to the end of the screw (121) that extends into the first flow channel (114). Along the axial direction of the valve needle body (111), the third limiting member (122) is located between the first limiting member (112) and the second limiting member (113). An elastic component (13) is disposed in the first flow channel (114) and located on the side of the screw (121) facing the second limiting member (113). The elastic component (13) has a limiting hole (130). The second limiting member (113) passes through the limiting hole (130) and is movable relative to the limiting hole (130) along the axial direction of the valve needle body (111).

2. The valve needle structure according to claim 1, characterized in that, The elastic component (13) includes an elastic element (131) and a limiting seat (132) arranged along the axial direction of the valve needle body (111). The limiting seat (132) is located on the side of the elastic element (131) facing the screw (121). The elastic element (131) is used to drive the limiting seat (132) to move toward the screw (121). At least a portion of the limiting hole (130) is formed on the limiting seat (132). When the third limiting element (122) abuts against the first limiting element (112), the screw assembly (12) is spaced apart from the limiting seat (132), or the limiting seat (132) is spaced apart from the elastic element (131).

3. The valve needle structure according to claim 2, characterized in that, All of the limiting holes (130) are formed on the limiting seat (132).

4. The valve needle structure according to claim 2, characterized in that, The limiting seat (132) has a mating hole, and the mating hole has an opening on the side facing the elastic member (131). At least a portion of the elastic member (131) covers the opening to define the limiting hole (130).

5. The valve needle structure according to claim 1, characterized in that, The dimension of the limiting hole (130) in the axial direction of the valve needle body (111) is greater than the outer diameter of the second limiting member (113).

6. The valve needle structure according to claim 5, characterized in that, One end of the elastic component (13) in the length direction abuts against the inner bottom wall of the first flow channel (114), and the other end is movable in the axial direction of the valve needle body (111). When the second limiting member (113) abuts against the side wall of the limiting hole (130) away from the screw assembly (12), the elastic force of the elastic component (13) does not act on the screw assembly (12).

7. The valve needle structure according to claim 1, characterized in that, The second limiting member (113) extends in the radial direction of the valve needle body (111), and the cross-section of the second limiting member (113) is an open annular along the extension direction of the second limiting member (113).

8. The valve needle structure according to claim 1, characterized in that, The second limiting member (113) includes at least one limiting shaft, one end of which is connected to the inner peripheral wall of the first flow channel (114), and the other end extends toward the center line of the valve needle body (111). The limiting hole (130) includes at least one sub-hole, the limiting shaft is located in the sub-hole, and the sub-hole corresponds to the limiting shaft one by one.

9. The valve needle structure according to claim 8, characterized in that, The number of limiting shafts is two, and the two limiting shafts are arranged opposite each other along the radial direction of the valve needle body (111) and are an integral part.

10. An electronic expansion valve, characterized in that, include: The housing (2) has a first cavity (21), a second cavity (22), a connecting hole (23), and a valve port (24). The first cavity (21) and the second cavity (22) are arranged in the axial direction of the housing (2). The connecting hole (23) is provided on the peripheral wall of the first cavity (21) and communicates with the first cavity (21). The valve port (24) is provided at the end of the first cavity (21) away from the second cavity (22). According to any one of claims 1-9, the valve needle structure (1) is disposed in the housing (2), and a portion of the valve needle assembly (11) extends into the first cavity (21) for opening or closing the valve port (24); A drive assembly (3) is disposed on the housing (2) and is used to drive the screw assembly (12) to move along the axial direction of the housing (2).

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