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, and the axial end surface of valve needle is equipped with first flow channel, and the inner peripheral wall of first flow channel is equipped with limit ring, screw rod subassembly, screw rod subassembly includes screw rod and a plurality of rolling pieces, and the one end of screw rod extension direction is worn in limit ring, and the one end of screw rod that rolling piece is connected in first flow channel is inserted, and a plurality of rolling pieces are spaced apart in the circumferential direction of screw rod, and a plurality of rolling pieces all are located the one side of limit ring towards first flow channel inner bottom wall, and the outer peripheral wall of rolling piece is suitable with the one side end surface of limit ring towards first flow channel inner bottom wall and rolls and contacts, elastic component, and elastic component is located in first flow channel and is located the one side of rolling piece and is away from limit ring, and elastic component is used for driving screw rod and moving towards the direction of being away from valve needle. 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 valve needle by the screw 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, wherein a first flow channel is provided on the axial end face of the valve needle, and a limiting ring is provided on the inner peripheral wall of the first flow channel; a screw assembly, wherein the screw assembly includes a screw and a plurality of rolling elements, the screw extending along the axial direction of the valve needle, one end of the screw extending in the direction of extension passing through the limiting ring, the rolling elements being connected to the end of the screw extending into the first flow channel, the axial direction of the rolling elements being perpendicular to the extension direction of the screw, the plurality of rolling elements being spaced apart in the circumferential direction of the screw, the plurality of rolling elements being located on the side of the limiting ring facing the inner bottom wall of the first flow channel, and the outer peripheral wall of the rolling elements being adapted to roll contact with the end face of the limiting ring facing the inner bottom wall of the first flow channel; and an elastic component, wherein the elastic component is disposed in the first flow channel and located on the side of the rolling elements away from the limiting ring, the elastic component being adapted to abut against the screw and drive the screw to move in a direction away from the valve needle.

[0006] According to the valve needle structure of this utility model embodiment, multiple rolling elements are provided at one end of the screw that extends into the first flow channel. The multiple rolling elements are all located on the side of the limiting ring facing the bottom wall of the first flow channel. The outer peripheral wall of the rolling elements is adapted to roll contact with the end face of the limiting ring facing the bottom wall of the first flow channel. This can transform the sliding friction between the screw and the limiting ring in the prior art into rolling friction between the rolling elements and the limiting ring. This can reduce the frictional torque, reduce the frictional force at the moment of valve opening, ensure the normal drive of the valve needle by the screw assembly, reduce the risk of valve jamming, improve the valve opening performance of the electronic expansion valve, and relatively reduce 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 screw includes a rod body and a plurality of connecting shafts. The rod body extends along the axial direction of the valve needle, and one end of the rod body extending in the direction of extension passes through the limiting ring. The connecting shafts are connected to one end of the rod body that extends into the first flow channel and extend in a direction away from the centerline of the rod body. The plurality of connecting shafts are spaced apart in the circumferential direction of the screw, and a plurality of rolling elements are connected to at least a portion of the connecting shafts at the end away from the rod body.

[0008] In some embodiments, there are two connecting shafts, which are arranged opposite each other along the radial direction of the rod body and are integral parts. The ends of the two connecting shafts facing away from each other are provided with the rolling element.

[0009] In some embodiments, the rolling element is a bushing, and the bushing is clearance-fitted with the connecting shaft.

[0010] In some embodiments, the bushing includes a surrounding portion and a protruding portion. The surrounding portion is sleeved on the connecting shaft and extends in the circumferential direction of the connecting shaft. The protruding portion is connected to one end of the surrounding portion opposite to the rod body and protrudes in a direction opposite to the surrounding portion.

[0011] In some embodiments, the end of the connecting shaft opposite to the centerline of the rod body has a flange extending radially outward toward the connecting shaft, and the rolling element is located on the side of the flange closer to the centerline of the rod body.

[0012] In some embodiments, the rolling element is a bearing, the inner ring of the bearing is fixedly connected to the connecting shaft, and the outer ring of the bearing is adapted to roll contact with the side end face of the limiting ring facing the bottom wall of the first flow channel.

[0013] In some embodiments, the elastic component includes: a ejector pin disposed within the first flow channel, one end of the ejector pin facing the limiting ring being adapted to abut against the screw; and an elastic member disposed within the first flow channel, one end of the elastic member along its length abutting against the inner bottom wall of the first flow channel, and the other end abutting against the ejector pin, for driving the ejector pin to abut against the screw.

[0014] The electronic expansion valve according to this utility model 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 extends into the first cavity for opening or closing the valve port; and a drive assembly disposed on the housing for driving the screw to move along the axial direction of the housing.

[0015] According to the embodiment of the present invention, the electronic expansion valve, by providing the above-mentioned valve needle structure, has multiple rolling elements at one end of the screw that extends into the first flow channel. The multiple rolling elements are all located on the side of the limiting ring facing the bottom wall of the first flow channel. The outer peripheral wall of the rolling elements is adapted to roll contact with the end face of the limiting ring facing the bottom wall of the first flow channel. This can transform the sliding friction between the screw and the limiting ring in the prior art into rolling friction between the rolling elements and the limiting ring, thereby reducing the frictional torque, reducing the frictional force at the moment of valve opening, ensuring the normal drive of the valve needle by the screw assembly, reducing the risk of valve jamming, improving the valve opening performance of the electronic expansion valve, and relatively reducing the starting current of the electronic expansion valve.

[0016] In addition, the electronic expansion valve according to this utility model may also have the following additional technical features: In some embodiments, the valve needle is further provided with a second flow channel, one end of the second flow channel along the axial direction of the valve needle is connected to the first flow channel, and the other end is connected to the valve port. The inner diameter of the second flow channel is smaller than the inner diameter of the first flow channel, and the end of the elastic component facing away from the screw abuts against the stepped surface between the first flow channel and the second flow channel.

[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 3 This 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 and a rolling element are 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 invention, wherein the valve needle and a rolling element are not shown.

[0019] Figure label: 100. Electronic expansion valve; 1. Valve needle structure; 11. Valve needle; 111. First flow channel; 112. Limiting ring; 113. Second flow channel; 12. Screw assembly; 121. Screw; 1211. Rod body; 1212. Connecting shaft; 1213. Ball cap; 1214. Fixing hole; 122. Rolling element; 123. Bushing; 1231. Surrounding part; 1232. Protrusion; 124. Bearing; 13. Elastic component; 131. Ejector pin; 1311. First section; 1312. Second section; 132. Elastic component; 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 , Figure 5 and Figure 8 As shown, the valve needle structure 1 according to an embodiment of the present invention includes a valve needle 11, a screw assembly 12, and an elastic assembly 13.

[0026] Specifically, see the attached document. Figure 3 and attached Figure 4 As shown, valve needle 11 is along direction a (e.g.) Figure 3 As shown, the valve needle 11 extends to the axial end face of which a first flow channel 111 is provided. A limiting ring 112 is provided on the inner peripheral wall of the first flow channel 111. The limiting ring 112 is located at the end of the first flow channel 111 away from the inner bottom wall, and the limiting ring 112 extends into a ring along the circumferential direction of the valve needle 11.

[0027] Further, see attached document. Figure 4 and attached Figure 8 As shown, the screw assembly 12 includes a screw 121 and a plurality of rolling elements 122. The screw 121 is along the axial direction of the valve needle 11 (see attached figure). Figure 4 The screw 121 extends in the direction shown in Figure a, and extends in the direction shown in the attached figure (see attached figure). Figure 4 One end of the screw 121 (in direction a) is inserted into the limiting ring 112. A rolling element 122 is connected to the end of the screw 121 that extends into the first flow channel 111. The axial direction of the rolling element 122 is perpendicular to the extension direction of the screw 121. Multiple rolling elements 122 are spaced apart circumferentially from the screw 121. All rolling elements 122 are located on the side of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. The outer peripheral wall of the rolling element 122 is adapted to roll contact with the end face of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. For example, the number of rolling elements 122 can be two, three, four, or five.

[0028] Furthermore, see the attached document. Figure 4 As shown, the elastic component 13 is disposed in the first flow channel 111 and located on one side of the rolling element 122 away from the limiting ring 112. One end of the elastic component 13 away from the limiting ring 112 abuts against the inner bottom wall of the first flow channel 111. The elastic component 13 is adapted to abut against the screw 121 and is used to drive the screw 121 to move in the direction away from the valve needle 11, which can ensure the sealing of the valve needle 11 to the valve port 24 of the electronic expansion valve 100.

[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] The valve needle structure 1 of this utility model has multiple rolling elements 122 at one end of the screw 121 that extends into the first flow channel 111. The multiple rolling elements 122 are all located on the side of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. The outer peripheral wall of the rolling element 122 is adapted to roll contact with the end face of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. This can transform the sliding friction between the screw 121 and the limiting ring 112 in the prior art into rolling friction between the rolling element 122 and the limiting ring 112. This can 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 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.

[0031] Understandably, as the valve needle structure 1 gradually closes the valve port 24, the screw assembly 12 rotates, causing the valve needle 11 and the elastic component 13 to move together toward the valve port 24. At this time, the rolling element 122 is always in rolling contact with the limiting ring 112 until the valve needle 11 blocks the valve port 24. The valve needle 11 can no longer move toward the direction away from the screw 121. The screw assembly 12 continues to rotate, compressing the elastic component 13, causing the rolling element 122 to be separated from the limiting ring 112, generating a pre-tightening force, 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, resetting the elastic component 13 until the rolling element 122 abuts against the limiting ring 112. Then, the screw assembly 12 continues to move in the direction away from the valve port 24, driving the valve needle 11 to move in the direction away from the valve port 24, slowly opening the valve port 24.

[0033] According to the valve needle structure 1 of this utility model embodiment, a plurality of rolling elements 122 are provided at one end of the screw 121 that extends into the first flow channel 111. The plurality of rolling elements 122 are all located on the side of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. The outer peripheral wall of the rolling element 122 is adapted to roll contact with the end face of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. This can transform the sliding friction between the screw 121 and the limiting ring 112 in the prior art into rolling friction between the rolling element 122 and the limiting ring 112. This can 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 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.

[0034] In some embodiments of this utility model, reference is made to the appendix. Figure 4 and attached Figure 8As shown, the screw 121 includes a rod body 1211 and a plurality of connecting shafts 1212. The rod body 1211 extends along the axial direction of the valve needle 11. The extension direction of the rod body 1211 is shown in the attached figure. Figure 4 One end of the screw (in direction a) is inserted into the limiting ring 112. The connecting shaft 1212 is connected to one end of the rod body 1211 that extends into the first flow channel 111. The connecting shaft 1212 extends in a direction away from the centerline of the rod body 1211. Multiple connecting shafts 1212 are spaced apart in the circumferential direction of the screw 121. Multiple rolling elements 122 are connected to at least a portion of the connecting shafts 1212 at the ends away from the rod body 1211. The connecting shafts 1212 are configured to accommodate the rolling elements 122. This facilitates the connection of the rolling element 122 to the rod body 1211, ensuring that the rod body 1211 can drive the rolling element 122 to rotate together in the circumferential direction of the rod body 1211, thereby ensuring the rolling contact between the rolling element 122 and the limiting ring 112. The arrangement of multiple connecting shafts 1212 and multiple rolling elements 122 can increase the rolling contact points between the screw 121 and the limiting ring 112, ensuring the force balance between the limiting ring 112 and the screw assembly 12, and ensuring the reliability and stability of the valve needle structure 1.

[0035] For example, there can be two connecting shafts 1212, which are arranged opposite each other along the radial direction of the rod body 1211, and each of the two connecting shafts 1212 has a rolling element 122 at the end opposite to each other; there can be three connecting shafts 1212, which are evenly spaced along the circumferential direction of the rod body 1211, and each of the connecting shafts 1212 has a rolling element 122 at the end opposite to the rod body 1211; there can be four connecting shafts 1212, which are evenly spaced along the circumferential direction of the rod body 1211, and the two radially opposite connecting shafts 1212 have a rolling element 122 at the end opposite to the rod body 1211.

[0036] In a further embodiment of this utility model, reference is made to the appendix. Figure 4As shown, the end of the rod body 1211 that extends into the first flow channel 111 has a fixing hole 1214. The fixing hole 1214 is located on the side of the limiting ring 112 facing the bottom wall of the first flow channel 111. The fixing hole 1214 penetrates the rod body 1211 in the radial direction. There are two connecting shafts 1212. The two connecting shafts 1212 are arranged opposite each other in the radial direction of the rod body 1211 and are integral parts. The two connecting shafts 1212 are formed as pins. The pins pass through the fixing hole 1214 and are interference-fitted with the rod body 1211. Both ends of the pins extend beyond the rod body 1211 in the axial direction. The ends of the two connecting shafts 1212 that are opposite to each other are provided with rolling elements 122. In this way, while ensuring the force balance of the limiting ring 112 and the screw assembly 12, the number of parts of the screw assembly 12 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.

[0037] In a further embodiment of this utility model, reference is made to the appendix. Figure 6 As shown, the rolling element 122 is a bushing 123. The bushing 123 is clearance-fitted with the connecting shaft 1212. The bushing 123 is rotatable relative to the connecting shaft 1212. On the one hand, the bushing 123 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 123 is simple and quick to assemble. It can be directly sleeved on the end of the connecting shaft 1212 away from the center line of the rod body 1211, 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.

[0038] In a further embodiment of this utility model, reference is made to the appendix. Figure 6 As shown, the bushing 123 includes a surrounding portion 1231 and a protruding portion 1232. The surrounding portion 1231 is sleeved on the connecting shaft 1212 and extends along the circumferential direction of the connecting shaft 1212. The protruding portion 1232 is connected to one end of the surrounding portion 1231 away from the rod body 1211. The protruding portion 1232 protrudes in the direction away from the surrounding portion 1231. The provision of the protruding portion 1232 can reduce the gap between the surrounding portion 1231 and the inner peripheral wall of the first flow channel 111, reduce the possibility of the bushing 123 falling off from the gap between the connecting shaft 1212 and the inner peripheral wall of the first flow channel 111, and prevent the bushing 123 from falling off the connecting shaft 1212.

[0039] Preferably, refer to the appendix Figure 6As shown, a spherical crown 1213 is formed at one end of the connecting shaft 1212 away from the center line of the rod body 1211. The spherical crown 1213 refers to the curved surface remaining after a sphere is cut by a plane. The side surface of the protrusion 1232 facing the surrounding part 1231 fits with the spherical crown 1213, so that the spherical crown 1213 can support the protrusion 1232, prevent the protrusion 1232 from sinking, and ensure the effectiveness of the protrusion 1232 in preventing it from falling off.

[0040] In a further embodiment of this utility model, the end of the connecting shaft 1212 away from the center line of the rod body 1211 has a flange. The flange extends radially outward toward the connecting shaft 1212. The rolling element 122 is located on the side of the flange close to the center line of the rod body 1211. The flange extends along the circumferential direction of the connecting shaft 1212 to prevent the rolling element 122 from coming off in the direction away from the center line of the rod body 1211, ensuring the reliability of the installation of the rolling element 122. It can also prevent the rolling element 122 from contacting the inner circumferential wall of the first flow channel 111, reducing the possibility of friction between the rolling element 122 and the inner wall of the first flow channel 111, relatively reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 for the valve needle 11, reducing the risk of valve jamming, and improving the valve opening performance of the electronic expansion valve 100.

[0041] In a further embodiment of this utility model, reference is made to the appendix. Figure 9 As shown, the rolling element 122 is a bearing 124. The inner ring of the bearing 124 is fixedly connected to the connecting shaft 1212. The outer ring of the bearing 124 is adapted to roll contact with the end face of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. Through the interference fit between the inner ring of the bearing 124 and the connecting shaft 1212, the outer ring of the bearing 124 can rotate relative to the connecting shaft 1212. This ensures that the outer peripheral wall of the rolling element 122 rolls in contact with the limiting ring 112, making the connection between the rolling element 122 and the connecting shaft 1212 more reliable. It also prevents the rolling element 122 from coming off the connecting shaft 1212 after assembly, ensuring the reliability and stability of the screw assembly 12 and improving the reliability of the valve needle structure 1.

[0042] It should be noted that since the bearing 124 and the connecting shaft 1212 are relatively fixed in the length direction of the connecting shaft 1212, the bearing 124 can be prevented from coming off the connecting shaft 1212, thereby preventing the bearing 124 from contacting the inner peripheral wall of the first flow channel 111, reducing the possibility of friction between the bearing 124 and the inner wall of the first flow channel 111, relatively reducing the frictional force at the moment of valve opening, ensuring the normal drive of the screw assembly 12 for the valve needle 11, reducing the risk of valve jamming, and improving the valve opening performance of the electronic expansion valve 100.

[0043] In some embodiments of this utility model, reference is made to the appendix. Figure 4 and attached Figure 6As shown, the elastic component 13 includes a ejector pin 131 and an elastic element 132. The ejector pin 131 is disposed within the first flow channel 111, located on the side of the screw 121 facing away from the bottom wall of the first flow channel 111. One end of the ejector pin 131 facing the limiting ring 112 is adapted to abut against the screw 121. The elastic element 132 is disposed within the first flow channel 111, and the length direction of the elastic element 132 (see attached diagram) Figure 4 One end of the elastic element 132 (in the direction shown in a) abuts against the inner bottom wall of the first flow channel 111, and the other end abuts against the ejector pin 131. This is used to drive the ejector pin 131 to abut against the screw 121, which can realize a flexible connection between the screw 121 and the valve needle 11. Compared with the direct fixed connection between the screw 121 and the valve needle 11, the elastic element 132 can directly abut against the ejector pin 131 and the screw 121, eliminating gaps, avoiding tolerances, and making the screw 121 more free.

[0044] Further, see attached document. Figure 4 and attached Figure 6 As shown, the ejector pin 131 includes a first segment 1311 and a second segment 1312. The first segment 1311 extends along the axial direction of the valve needle 11. An elastic element 132 is sleeved on the outside of the first segment 1311. The second segment 1312 is connected to the end of the first segment 1311 facing the screw 121. In the direction from the second segment 1312 to the first segment 1311, the cross-sectional area of ​​the second segment 1312 gradually increases. The elastic element 132 abuts against the end of the second segment 1312 away from the first segment 1311. The end of the second segment 1312 away from the first segment 1311 abuts against the screw 121 and is spaced apart from the rolling element 122. This can ensure that the screw 121 can drive the elastic component 13 to move normally, while avoiding contact between the rolling element 122 and the ejector pin 131 as much as possible. This avoids the normal movement of the rolling element 122 due to friction between the rolling element 122 and the ejector pin 131, thus ensuring the reliability of the valve needle structure 1.

[0045] This utility model also proposes an electronic expansion valve 100 having the valve needle structure 1 of the above embodiments.

[0046] like Figure 2 and 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.

[0047] Specifically, see the attached document. Figure 1 Appendix Figure 2 and attached Figure 7 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 2Arranged 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.

[0048] Further, see attached document. Figure 2 and attached Figure 7 As shown, the valve needle structure 1 is located inside the housing 2, and part of the valve needle 11 extends into the first cavity 21 to open or close the valve port 24. The axial direction of the valve needle 11 is the same as the axial direction of the housing 2. When the valve needle 11 closes the valve port 24, the connecting hole 23 and the valve port 24 are no longer connected, and the medium cannot flow into the first cavity 21 from the valve port 24, 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 121 to move along the axial direction of the housing 2.

[0049] Under the drive of the drive assembly 3, the screw 121 drives the valve needle 11 to move along the axial direction of the housing 2. When the valve needle 11 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 11 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.

[0050] 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 7 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.

[0051] It is understandable that, such as Figure 2 As 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.

[0052] According to the embodiment of the present invention, the electronic expansion valve 100 is provided with the above-mentioned valve needle structure 1. Multiple rolling elements 122 are provided at one end of the screw 121 that extends into the first flow channel 111. All rolling elements 122 are located on the side of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. The outer peripheral wall of the rolling element 122 is adapted to roll contact with the end face of the limiting ring 112 facing the inner bottom wall of the first flow channel 111. This transforms the sliding friction between the screw 121 and the limiting ring 112 in the prior art into rolling friction between the rolling element 122 and the limiting ring 112. This reduces frictional torque, reduces frictional force at the moment of valve opening, ensures normal drive of the valve needle 11 by the screw assembly 12, 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.

[0053] In some embodiments of this utility model, reference is made to the appendix. Figure 2 and attached Figure 7 As shown, the valve needle 11 is also provided with a second flow channel 113. One end of the second flow channel 113 along the axial direction of the valve needle 11 is connected to the first flow channel 111, and the other end is connected to the valve port 24. The inner diameter of the second flow channel 113 is smaller than the inner diameter of the first flow channel 111. 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 111 and the second flow channel 113.

[0054] Understandably, the medium can flow into the second flow channel 113 from the valve port 24 and flow along the second flow channel 113 to the first flow channel 111. Finally, the second cavity 22 of the first flow channel 111 can keep the air pressure in the second cavity 22 consistent with the air pressure on the side of the valve needle 11 away from the second cavity 22, ensuring that the valve needle 11 is always in a pressure balance state during the switching process, and avoiding affecting the normal movement of the valve needle 11 along the axial direction of the housing 2.

[0055] Understandably, during the gradual closing process of the electronic expansion valve 100: the screw 121 moves towards the valve port 24. Since the elastic element 132 is relatively hard, it is not compressed at this time. This allows the valve needle 11, the ejector pin 131, and the elastic element 132 to move together towards the valve port 24 as a whole until the valve needle 11 blocks the valve port 24. The valve needle 11 can no longer move, but under the drive of the drive assembly 3, the screw 121 continues to rotate and move towards the valve port 24. The rolling element 122 slowly separates from the limit ring 112, driving the ejector pin 131 to compress the elastic element 132, generating a preload force and reserving a set valve opening pulse. This ensures that the electronic expansion valve 100 has sufficient sealing force to block the valve port 24 when the power is off or when it is not running, thus preventing media leakage.

[0056] The process of the electronic expansion valve 100 gradually opening: the screw 121 moves away from the valve port 24, the elastic element 132 gradually resets, and then the screw 121 continues to move away from the valve port 24 until the rolling element 122 rolls into contact with the limiting ring 112. The screw 121 drives the valve needle 11 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 11 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.

[0057] 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.

[0058] 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.

[0059] 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 (11) is provided with a first flow channel (111) on its axial end face, and a limiting ring (112) is provided on the inner peripheral wall of the first flow channel (111). A screw assembly (12) includes a screw (121) and a plurality of rolling elements (122). The screw (121) extends along the axial direction of the valve needle (11). One end of the screw (121) extending in the direction of extension passes through the limiting ring (112). The rolling elements (122) are connected to one end of the screw (121) that extends into the first flow channel (111). The axial direction of the rolling elements (122) is perpendicular to the extension direction of the screw (121). The plurality of rolling elements (122) are spaced apart in the circumferential direction of the screw (121). The plurality of rolling elements (122) are all located on the side of the limiting ring (112) facing the inner bottom wall of the first flow channel (111). The outer peripheral wall of the rolling element (122) is adapted to roll contact with the end face of the limiting ring (112) facing the inner bottom wall of the first flow channel (111). An elastic component (13) is disposed in the first flow channel (111) and located on the side of the rolling element (122) away from the limiting ring (112). The elastic component (13) is adapted to abut against the screw (121) to drive the screw (121) to move in a direction away from the valve needle (11).

2. The valve needle structure according to claim 1, characterized in that, The screw (121) includes a rod body (1211) and a plurality of connecting shafts (1212). The rod body (1211) extends along the axial direction of the valve needle (11). One end of the rod body (1211) extending in the direction of extension passes through the limiting ring (112). The connecting shafts (1212) are connected to one end of the rod body (1211) that extends into the first flow channel (111). The connecting shafts (1212) extend in a direction away from the center line of the rod body (1211). The plurality of connecting shafts (1212) are spaced apart in the circumferential direction of the screw (121). A plurality of rolling elements (122) are connected to at least a portion of the connecting shafts (1212) at the end away from the rod body (1211).

3. The valve needle structure according to claim 2, characterized in that, There are two connecting shafts (1212). The two connecting shafts (1212) are arranged opposite each other along the radial direction of the rod body (1211) and are an integral piece. The rolling element (122) is provided at the opposite end of the two connecting shafts (1212).

4. The valve needle structure according to claim 2, characterized in that, The rolling element (122) is a bushing (123), and the bushing (123) is clearance-fitted with the connecting shaft (1212).

5. The valve needle structure according to claim 4, characterized in that, The bushing (123) includes a surrounding portion (1231) and a protruding portion (1232). The surrounding portion (1231) is sleeved on the connecting shaft (1212) and extends in the circumferential direction of the connecting shaft (1212). The protruding portion (1232) is connected to the end of the surrounding portion (1231) opposite to the rod body (1211) and protrudes in a direction opposite to the surrounding portion (1231).

6. The valve needle structure according to claim 2, characterized in that, The end of the connecting shaft (1212) opposite to the center line of the rod body (1211) has a flange, which extends radially outward toward the connecting shaft (1212), and the rolling element (122) is located on the side of the flange closer to the center line of the rod body (1211).

7. The valve needle structure according to claim 2, characterized in that, The rolling element (122) is a bearing (124). The inner ring of the bearing (124) is fixedly connected to the connecting shaft (1212). The outer ring of the bearing (124) is adapted to roll contact with the side end face of the limiting ring (112) facing the inner bottom wall of the first flow channel (111).

8. The valve needle structure according to claim 1, characterized in that, The elastic component (13) includes: A ejector pin (131) is disposed in the first flow channel (111), and one end of the ejector pin (131) facing the limiting ring (112) is adapted to abut against the screw (121); An elastic element (132) is disposed in the first flow channel (111). One end of the elastic element (132) in the length direction abuts against the inner bottom wall of the first flow channel (111), and the other end abuts against the ejector pin (131), for driving the ejector pin (131) to abut against the screw (121).

9. 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 1-8, the valve needle structure (1) is disposed in the housing (2), and a portion of the valve needle (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 (121) to move along the axial direction of the housing (2).

10. The electronic expansion valve according to claim 9, characterized in that, The valve needle (11) is also provided with a second flow channel (113). One end of the second flow channel (113) along the axial direction of the valve needle (11) is connected to the first flow channel (111), and the other end is connected to the valve port (24). The inner diameter of the second flow channel (113) is smaller than the inner diameter of the first flow channel (111). The end of the elastic component (13) away from the screw (121) abuts against the stepped surface between the first flow channel (111) and the second flow channel (113).

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