Valve needle structure and electronic expansion valve having the same

Abstract

The utility model discloses a valve needle structure and electronic expansion valve who has it, valve needle structure includes: guide sleeve, the inner peripheral wall of guide sleeve is equipped with stop piece, and stop piece is integral with guide sleeve, bearing, bearing is located in the guide sleeve, and bearing is located one side of stop piece along the axial direction of guide sleeve, screw rod, screw rod rotatably is arranged in the guide sleeve and extends along the axial direction of guide sleeve, and screw rod is arranged in the bearing, first valve needle, first valve needle is arranged in the guide sleeve and extends along the axial direction of guide sleeve, and first valve needle is located the side of stop piece away from the bearing, and first valve needle is movable along the axial direction of guide sleeve, first elastic part, first elastic part is equipped between first valve needle and stop piece, is used for driving first valve needle and moves the direction away from screw rod. According to the valve needle structure of the utility model, can shorten assembly stroke, reduce the assembly difficulty of valve needle structure, improve the assembly efficiency of valve needle structure.

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 of flow control accuracy, the internal structure of valves is becoming increasingly complex, increasing the difficulty of valve assembly. 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 shorten the assembly stroke, reduce the assembly difficulty of the valve needle structure, and improve the assembly efficiency of the valve needle structure.

[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 guide sleeve, wherein a limiting member is provided on the inner peripheral wall of the guide sleeve, and the limiting member and the guide sleeve are integrally formed; a bearing, wherein the bearing is disposed inside the guide sleeve and is located on one side of the limiting member along the axial direction of the guide sleeve; a screw, wherein the screw is rotatably disposed inside the guide sleeve and extends along the axial direction of the guide sleeve, and the screw is disposed inside the bearing; a first valve needle, wherein the first valve needle is disposed inside the guide sleeve and extends along the axial direction of the guide sleeve, the first valve needle is located on the side of the limiting member opposite to the bearing, and the first valve needle is movable along the axial direction of the guide sleeve; and a first elastic member, wherein the first elastic member is disposed between the first valve needle and the limiting member, for driving the first valve needle to move in a direction opposite to the screw.

[0006] According to the valve needle structure of this utility model embodiment, the valve needle structure includes a guide sleeve, a bearing, a screw, a first valve needle, and a first elastic element. A limiting member is provided on the inner peripheral wall of the guide sleeve, and the limiting member is integral with the guide sleeve. The bearing and the screw are located on one side of the limiting member along the axial direction of the guide sleeve, and the first valve needle and the first elastic element are located on the other side along the axial direction of the guide sleeve. This can shorten the assembly stroke of the bearing, screw, first valve needle, and first elastic element, facilitate the assembly of the bearing, screw, first valve needle, and first elastic element, reduce the assembly difficulty of the valve needle structure, and improve the assembly efficiency of the valve needle structure. Furthermore, the screw, bearing, and guide sleeve can form modular components. Due to the differences between products, the performance can be adjusted by changing the length, diameter, and end shape of the first valve needle, achieving minimum cost to meet product platform expansion requirements. At the same time, the setting of the first elastic element can reduce the influence of the guide sleeve or screw eccentricity on the first valve needle, reduce the coaxiality requirement of the first valve needle, ensure the stability of the first valve needle movement, and enable the first valve needle to have sufficient freedom in the axial and radial directions. This optimizes the stall and jamming phenomenon of the valve needle structure, allows the valve needle to better adjust its posture and cooperate with the valve port, optimizes the flow control accuracy of the valve needle structure in the opening and closing process of the electronic expansion valve, and improves the overall performance of the electronic expansion valve.

[0007] In addition, the valve needle structure of this utility model may also have the following additional technical features:

[0008] In some embodiments, the outer peripheral wall of the first valve needle has a protrusion, and the end of the first elastic member opposite to the limiting member abuts against the protrusion. The valve needle structure further includes: a first bushing and a second bushing, the first bushing and the second bushing being respectively disposed at the axial ends of the guide sleeve, the screw passing through the first bushing, the first bushing being located on the side of the bearing opposite to the limiting member, for restricting the bearing from moving in the direction opposite to the limiting member, the first valve needle passing through the second bushing, and the second bushing being located on the side of the protrusion opposite to the first elastic member.

[0009] In some embodiments, the limiting member has a limiting boss on the side facing the first valve needle, and the first elastic member is sleeved on the limiting boss; and / or, the limiting member has a limiting groove on the side away from the first valve needle, the outer ring of the bearing is located outside the limiting groove, and the inner ring of the bearing is located inside the limiting groove.

[0010] In some embodiments, the end of the first valve needle opposite to the screw has a sealing section, and the cross-sectional area of ​​the sealing section gradually decreases in the direction from the screw to the first valve needle.

[0011] This utility model also provides an electronic expansion valve having the above-described embodiments.

[0012] According to the embodiment of the present invention, the electronic expansion valve, by providing the aforementioned valve needle structure, includes a guide sleeve, a bearing, a screw, a first valve needle, and a first elastic element. A limiting member is provided on the inner peripheral wall of the guide sleeve, and the limiting member is integral with the guide sleeve. The bearing and screw are located on one side of the limiting member along the axial direction of the guide sleeve, and the first valve needle and the first elastic element are located on the other side along the axial direction of the guide sleeve. This shortens the assembly stroke of the bearing, screw, first valve needle, and first elastic element, facilitating their assembly, reducing the assembly difficulty of the valve needle structure, and improving its assembly efficiency. Furthermore, the screw, bearing, and guide sleeve can form modular components. Due to product differentiation, performance can be adjusted by changing the length, diameter, and end shape of the first valve needle, achieving minimum cost to meet product platform expansion requirements. At the same time, the setting of the first elastic element can reduce the influence of the guide sleeve or screw eccentricity on the first valve needle, reduce the coaxiality requirement of the first valve needle, ensure the stability of the first valve needle movement, and enable the first valve needle to have sufficient freedom in the axial and radial directions. This optimizes the stall and jamming phenomenon of the valve needle structure, allows the valve needle to better adjust its posture and cooperate with the valve port, optimizes the flow control accuracy of the valve needle structure in the opening and closing process of the electronic expansion valve, and improves the overall performance of the electronic expansion valve.

[0013] In addition, the electronic expansion valve according to this utility model may also have the following additional technical features:

[0014] In some embodiments, the electronic expansion valve further includes: a housing having a first cavity, a second cavity, a first communicating hole, and a first valve port, the first cavity and the second cavity being arranged in the axial direction of the housing, the first communicating hole being disposed on the peripheral wall of the first cavity and communicating with the first cavity, and the first valve port being disposed at one end of the first cavity opposite to the second cavity; and a second valve needle disposed within the housing and partially extending into the first cavity, the second valve needle being movable along the axial direction of the housing to open or close the first valve port, the second valve needle having a first... The housing has three chambers. The second valve needle has a second valve port communicating with the third chamber on its axial end face away from the second chamber. The peripheral wall of the second valve needle has a second communicating hole communicating with the third chamber and the first chamber. The valve needle structure passes through the second valve needle and is movable along the axial direction of the housing. A portion of the first valve needle is disposed in the third chamber to open or close the second valve port. The axial direction of the guide sleeve is the same as the axial direction of the housing. A drive assembly is disposed on the housing and is used to drive the screw to move along the axial direction of the housing.

[0015] In some embodiments, a first flow channel is provided on the end face of the second valve needle away from the first valve port, and a first limiting structure is provided at the end of the first flow channel away from the first valve port. The valve needle structure passes through the first flow channel, and a second limiting structure is provided on the outer peripheral wall of the guide sleeve. The second limiting structure is located on the side of the first limiting structure close to the first valve port, and the second limiting structure is adapted to abut against the surface of the first limiting structure facing the first valve port.

[0016] In some embodiments, the outer peripheral wall of the first valve needle has a protrusion, and the end of the first elastic member opposite to the limiting member abuts against the protrusion. The valve needle structure further includes a second bushing, the first valve needle passing through the second bushing, and the second bushing located on the side of the protrusion opposite to the first elastic member. When the first valve needle closes the second valve port, the valve needle structure has a first position and a second position. In the first position, the protrusion abuts against the second bushing, the first valve needle is spaced apart from the screw, and the second limiting structure is spaced apart from the inner wall of the first flow channel near the first valve port. In the second position, the protrusion is spaced apart from the second bushing.

[0017] In some embodiments, the second valve needle has a second flow channel, which communicates with the first valve port and is spaced apart from the third cavity and the second connecting hole. The guide sleeve has a third flow channel and a balance hole. The bearing, the first elastic element, part of the screw and part of the first valve needle are all disposed in the third flow channel. The third flow channel communicates with the end of the second flow channel opposite to the first valve port. The balance hole is disposed on the outer peripheral wall of the guide sleeve and is used to connect the third flow channel and the second cavity.

[0018] In some embodiments, the electronic expansion valve further includes: a housing having a first cavity, a second cavity, a first communicating hole, and a first valve port, the first cavity and the second cavity being arranged in the axial direction of the housing, the first communicating hole being disposed on the peripheral wall of the first cavity and communicating with the first cavity, the first valve port being disposed at one end of the first cavity opposite to the second cavity, the valve needle structure being disposed within the housing, and a portion of the first valve needle extending into the first cavity for opening or closing the first valve port, the axial direction of the guide sleeve being the same as the axial direction of the housing; and a drive assembly disposed on the housing for driving the screw to move along the axial direction of the housing.

[0019] 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

[0020] 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:

[0021] Figure 1 This is a perspective view of an electronic expansion valve according to an embodiment of the present utility model;

[0022] Figure 2 This is a front view of the electronic expansion valve according to an embodiment of the present utility model;

[0023] Figure 3 This is a cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model;

[0024] Figure 4 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the valve needle structure is in the second position;

[0025] Figure 5 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the valve needle structure is in a first position and the valve needle structure closes the second valve port;

[0026] Figure 6 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the valve needle structure opens the second valve port;

[0027] Figure 7 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the valve needle structure opens all the second valve ports and the second valve needle closes the first valve port;

[0028] Figure 8 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the second valve needle opens the first valve port.

[0029] Figure 9 This is a partial cross-sectional view of an electronic expansion valve according to an embodiment of the present utility model, wherein the second valve needle opens all of the first valve port;

[0030] Figure 10 This is a perspective view of the valve needle structure according to an embodiment of the present utility model;

[0031] Figure 11 This is a cross-sectional view of the valve needle structure according to an embodiment of the present utility model;

[0032] Figure 12 This is a cross-sectional view of the valve needle structure according to an embodiment of the present utility model, wherein the first valve needle, the first elastic member, and the second bushing are not shown.

[0033] Figure 13This is a perspective view of the guide sleeve of the valve needle structure according to an embodiment of the present utility model;

[0034] Figure 14 This is a cross-sectional view of the guide sleeve of the valve needle structure according to an embodiment of the present utility model;

[0035] Figure 15 This is a perspective view of the first valve needle according to an embodiment of the present utility model.

[0036] Figure 16 This is a perspective view of the first elastic element of the valve needle structure according to an embodiment of the present utility model;

[0037] Figure 17 This is a perspective view of the second bushing of the valve needle structure according to an embodiment of the present utility model.

[0038] Figure label:

[0039] 100. Electronic expansion valve;

[0040] 1. Valve needle structure; 11. Guide sleeve; 111. Limiting element; 112. Second limiting structure; 1121. Notch; 113. Third flow channel; 114. Balance hole; 12. Bearing; 13. Screw; 14. First valve needle; 141. Protrusion; 142. Sealing section; 15. First elastic element; 16. First bushing; 17. Second bushing;

[0041] 2. Housing; 21. First cavity; 22. Second cavity; 23. First connecting hole; 24. First valve port; 241. Sealing gasket;

[0042] 3. Second valve needle; 31. Third cavity; 32. Second valve port; 33. Second connecting hole; 34. First flow channel; 341. First limiting structure; 35. Second flow channel;

[0043] 4. Drive assembly; 41. Coil assembly; 42. Rotor assembly; 43. Guide component; 44. Nut;

[0044] 5. Second elastic element. Detailed Implementation

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] The valve needle structure 1 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0050] like Figure 3 , Figure 10 and Figure 11 As shown, the valve needle structure 1 according to an embodiment of the present invention is used in an electronic expansion valve 100 and includes a guide sleeve 11, a bearing 12, a screw 13, a first valve needle 14, and a first elastic element 15.

[0051] Specifically, see the attached document. Figure 11 As shown, the guide sleeve 11 is along the a direction (e.g. Figure 11 As shown, the guide sleeve 11 extends to the inner circumferential wall and is provided with a limiting member 111. The limiting member 111 and the guide sleeve 11 are integral parts. The bearing 12 is located inside the guide sleeve 11, and the bearing 12 is located along the axial direction of the limiting member 111 along the guide sleeve 11 (see attached figure). Figure 11On one side (as shown in direction a), the limiting member 111 can support the bearing 12 and restrict the bearing 12 from moving towards the other side of the limiting member 111. By making the limiting member 111 and the guide sleeve 11 an integral part, the number of parts of the valve needle structure 1 can be reduced, the assembly process of the valve needle structure 1 can be simplified, the assembly difficulty of the valve needle structure 1 can be reduced, and the assembly efficiency of the valve needle structure 1 can be improved. Preferably, the limiting member 111 extends along the circumferential direction of the guide sleeve 11, which can ensure the supporting and limiting effect of the limiting member 111 on the bearing 12.

[0052] Further, see attached document. Figure 12 As shown, the screw 13 is rotatably inserted into the guide sleeve 11 and extends along the axial direction of the guide sleeve 11. The screw 13 is inserted into the bearing 12 and fixedly connected to the inner ring of the bearing 12. The first valve needle 14 is inserted into the guide sleeve 11 and extends along the axial direction of the guide sleeve 11. The guide sleeve 11 can guide the first valve needle 14. The first valve needle 14 is located on the side of the limiting member 111 away from the bearing 12. The first valve needle 14 is movable along the axial direction of the guide sleeve 11.

[0053] It is understandable that the screw 13, bearing 12 and guide sleeve 11 move synchronously in the axial direction of the guide sleeve 11, while the first valve needle 14 can move in the axial direction of the guide sleeve 11. This allows the screw 13, bearing 12 and guide sleeve 11 to form modular components. Due to the differences between products, the performance can be adjusted by changing the length, diameter and end shape of the first valve needle 14, so as to meet the product platform expansion at the lowest cost.

[0054] It should be noted that, preferably, the screw 13, bearing 12 and guide sleeve 11 will not move relative to each other in the axial direction of the guide sleeve 11, but gaps within the tolerance range are allowed. Slight relative movement of the screw 13, bearing 12 and guide sleeve 11 in the axial direction of the guide sleeve 11 will not affect the overall performance.

[0055] Furthermore, see the attached document. Figure 11 and attached Figure 16 As shown, the first elastic element 15 is disposed between the first valve needle 14 and the limiting element 111, and is used to drive the first valve needle 14 to move in a direction away from the screw 13, which can ensure that the first valve needle 14 is aligned with the valve port of the electronic expansion valve 100 (e.g., Figure 3The sealing performance of the second valve port 32 shown is improved, and due to the presence of the first elastic element 15, the first valve needle 14 and the guide sleeve 11 can be in clearance fit, reducing the influence of the eccentricity of the guide sleeve 11 or the screw 13 on the first valve needle 14, reducing the coaxiality requirement of the first valve needle 14, ensuring the stability of the movement of the first valve needle 14, and allowing the first valve needle 14 to have sufficient freedom in the axial and radial directions, optimizing the stall and jamming phenomenon of the valve needle structure 1, enabling the valve needle to better adjust its posture and cooperate with the valve port, optimizing the flow control accuracy of the valve needle structure 1 in the switching process of the electronic expansion valve 100, and improving the overall performance of the electronic expansion valve 100.

[0056] Understandably, since the guide sleeve 11 has a limiting member 111 on its inner peripheral wall, the bearing 12 and the screw 13 are located on one side of the limiting member 111 along the axial direction of the guide sleeve 11, and the first valve needle 14 and the first elastic member 15 are located on the other side of the guide sleeve 11 along the axial direction. This allows the bearing 12 and the screw 13 to be installed into the guide sleeve 11 from one axial end of the guide sleeve 11, and the first valve needle 14 and the first elastic member 15 to be installed into the guide sleeve 11 from the other axial end of the guide sleeve 11. This can shorten the assembly stroke of the bearing 12, the screw 13, the first valve needle 14 and the first elastic member 15, facilitate the assembly of the bearing 12, the screw 13, the first valve needle 14 and the first elastic member 15, reduce the assembly difficulty of the valve needle structure 1, and improve the assembly efficiency of the valve needle structure 1.

[0057] According to the embodiment of the present invention, the valve needle structure 1 includes a guide sleeve 11, a bearing 12, a screw 13, a first valve needle 14, and a first elastic element 15. A limiting member 111 is provided on the inner peripheral wall of the guide sleeve 11, and the limiting member 111 is integral with the guide sleeve 11. The bearing 12 and the screw 13 are located on one side of the limiting member 111 along the axial direction of the guide sleeve 11, and the first valve needle 14 and the first elastic element 15 are located on the other side of the axial direction of the guide sleeve 11. This shortens the assembly stroke of the bearing 12, the screw 13, the first valve needle 14, and the first elastic element 15, facilitates the assembly of the bearing 12, the screw 13, the first valve needle 14, and the first elastic element 15, reduces the assembly difficulty of the valve needle structure 1, and improves the assembly efficiency of the valve needle structure 1. Furthermore, the screw 13, the bearing 12, and the guide sleeve 11 can form modular components. Due to the differences between products, the performance can be adjusted by changing the length, diameter, and end shape of the first valve needle 14, achieving minimum cost to meet product platform expansion requirements. Meanwhile, the first elastic element 15 can reduce the influence of the eccentricity of the guide sleeve 11 or screw 13 on the first valve needle 14, reduce the coaxiality requirement of the first valve needle 14, ensure the stability of the movement of the first valve needle 14, and enable the first valve needle 14 to have sufficient freedom in the axial and radial directions. This optimizes the stall and jamming phenomenon of the valve needle structure 1, allows the valve needle to better adjust its posture and cooperate with the valve port, optimizes the flow control accuracy of the valve needle structure 1 during the opening and closing process of the electronic expansion valve 100, and improves the overall performance of the electronic expansion valve 100.

[0058] In some embodiments of this utility model, reference is made to the appendix. Figure 10 Appendix Figure 11 and attached Figure 15 As shown, the outer peripheral wall of the first valve needle 14 has a protrusion 141, and the first elastic member 15 is sleeved on the first valve needle 14. One end of the first elastic member 15 that is away from the limiting member 111 abuts against the protrusion 141, which can ensure the reliability of the assembly of the first elastic member 15 and ensure the driving effect of the first elastic member 15 on the first valve needle 14.

[0059] Further, see attached document. Figure 10 Appendix Figure 11 and attached Figure 17As shown, the valve needle structure 1 also includes a first bushing 16 and a second bushing 17. The first bushing 16 and the second bushing 17 are respectively disposed at both ends of the guide sleeve 11. The screw 13 passes through the first bushing 16. The first bushing 16 is located on the side of the bearing 12 away from the limiting member 111, and is used to restrict the bearing 12 from moving in the direction away from the limiting member 111. The first bushing 16 and the limiting member 111 can respectively fix the bearing 12 from both sides along the axial direction of the guide sleeve 11, thereby ensuring The bearing 12 is reliably installed, realizing the modular design of the guide sleeve 11, screw 13, bearing 12 and first bushing 16. The first valve needle 14 is inserted into the second bushing 17. The second bushing 17 is located on the side of the protrusion 141 away from the first elastic member 15. The end face of the protrusion 141 facing the second bushing 17 is adapted to abut against the second bushing 17. The second bushing 17 can be used to prevent the first valve needle 14 from moving in the direction away from the screw 13, thereby preventing the first valve needle 14 from coming out of the guide sleeve 11.

[0060] It is understandable that the first bushing 16 and the second bushing 17 are respectively located at the two axial ends of the guide sleeve 11, which simplifies assembly and reduces the difficulty of sealing the two axial ends of the guide sleeve 11. Furthermore, since both the first bushing 16 and the second bushing 17 extend along the axial direction of the guide sleeve 11, the first bushing 16 can guide the screw 13 to a certain extent, reducing the probability of the screw 13 deviating. The second bushing 17 can guide the first valve needle 14 to a certain extent, reducing the probability of the first valve needle 14 deviating.

[0061] It should be noted that the first bushing 16 can directly abut against one side of the bearing 12's opposite-limiting member 111, or it can have a certain gap with one side of the bearing 12's opposite-limiting member 111. Neither of these conditions will affect the limiting effect of the first bushing 16 on the bearing 12.

[0062] It should be noted that the first bushing 16 and the guide sleeve 11 bracket are interference-fitted and / or welded together, and the second bushing 17 and the guide sleeve 11 bracket are interference-fitted and / or welded together.

[0063] In some embodiments of this utility model, the limiting member 111 has a limiting boss on the side facing the first valve needle 14, and the first elastic member 15 is sleeved on the limiting boss. The setting of the limiting boss can limit the first elastic member 15 in the radial direction, reduce the swaying amplitude of the first elastic member 15 in the radial direction, and avoid interference between the first elastic member 15 and the screw 13 or the inner ring of the bearing 12.

[0064] Furthermore, the side of the limiting member 111 facing away from the first valve needle 14 has a limiting groove. The outer ring of the bearing 12 is located outside the limiting groove, and the inner ring of the bearing 12 is located inside the limiting groove. The end face of the limiting member 111 without the limiting groove can support the outer ring of the bearing 12, preventing the bearing 12 from moving towards the first valve needle 14. The limiting groove of the limiting member 111 can accommodate the end of the screw 13 facing the first valve needle 14 and the inner ring of the bearing 12, preventing the limiting member 111 from interfering with the normal rotation of the inner ring of the bearing 12, thereby ensuring the normal rotation of the screw 13. Since the inner ring of the bearing 12 needs to be connected to the end of the screw 13 facing the first valve needle 14, the ends of the inner ring and the outer ring of the bearing 12 facing the first valve needle 14 are not flush. The setting of the limiting groove can ensure the supporting and fixing function of the limiting member 111 for the bearing.

[0065] In some embodiments, the limiting boss and the limiting groove are disposed opposite to each other in the axial direction of the guide sleeve 11, and the central region of the limiting member 111 has a through hole that passes through the limiting boss and the limiting groove.

[0066] In some embodiments, the limiting member 111 can be a partition integrally formed in the guide sleeve 11, with the central region of the partition recessed toward the first valve needle 14, such that the side of the recessed region toward the first valve needle 14 is formed as a limiting boss, and the side of the recessed region away from the first valve needle 14 is formed as a limiting groove.

[0067] In some embodiments of this utility model, reference is made to the appendix. Figure 11 and attached Figure 15 As shown, the end of the first valve needle 14 facing away from the screw 13 has a sealing section 142. In the direction from the screw 13 to the first valve needle 14, the cross-sectional area of ​​the sealing section 142 gradually decreases, gradually sealing the valve port of the electronic expansion valve 100 (e.g., ...). Figure 3 When the second valve port 32 shown is in use, the space occupied by the blocking section 142 in the valve port gradually increases, thereby gradually sealing the valve port and realizing the flow regulation of the electronic expansion valve 100 by the valve core structure.

[0068] This utility model also proposes an electronic expansion valve 100 having the valve needle structure 1 of the above embodiments.

[0069] According to the embodiment of the present invention, the electronic expansion valve 100 is provided with the above-mentioned valve needle structure 1. The valve needle structure 1 includes a guide sleeve 11, a bearing 12, a screw 13, a first valve needle 14, and a first elastic element 15. A limiting member 111 is provided on the inner peripheral wall of the guide sleeve 11. The limiting member 111 is integral with the guide sleeve 11. The bearing 12 and the screw 13 are located on one side of the limiting member 111 along the axial direction of the guide sleeve 11, and the first valve needle 14 and the first elastic element 15 are located on the other side of the axial direction of the guide sleeve 11. This can shorten the assembly stroke of the bearing 12, the screw 13, the first valve needle 14, and the first elastic element 15, facilitate the assembly of the bearing 12, the screw 13, the first valve needle 14, and the first elastic element 15, reduce the assembly difficulty of the valve needle structure 1, and improve the assembly efficiency of the valve needle structure 1. Furthermore, the screw 13, bearing 12, and guide sleeve 11 can form modular components. Due to product differentiation, performance can be adjusted by changing the length, diameter, and end shape of the first valve needle 14, achieving product platform expansion at minimal cost. Simultaneously, the first elastic element 15 reduces the impact of eccentricity of the guide sleeve 11 or screw 13 on the first valve needle 14, lowering the coaxiality requirement of the first valve needle 14. While ensuring the stability of the first valve needle 14's movement, it allows the first valve needle 14 sufficient freedom in the axial and radial directions, optimizing the stalling and jamming phenomena of the valve needle structure 1. This allows the valve needle to better adjust its posture and cooperate with the valve port, optimizing the flow control accuracy of the valve needle structure 1 during the switching process of the electronic expansion valve 100 and improving the overall performance of the electronic expansion valve 100.

[0070] In some embodiments of this utility model, reference is made to the appendix. Figure 3 As shown, the electronic expansion valve 100 also includes a housing 2, a second valve needle 3, and a drive assembly 4.

[0071] For details, please refer to the appendix. Figure 1 Appendix Figure 2 and attached Figure 3 As shown, the housing 2 can protect the internal structure of the electronic expansion valve 100, which helps to extend the service life of the electronic expansion valve 100. The housing 2 has a first cavity 21, a second cavity 22, a first connecting hole 23, and a first valve port 24. The first cavity 21 and the second cavity 22 are in the axial direction of the housing 2 (see attached figure). Figure 3 Arranged in the direction shown (a), the first connecting hole 23 is provided on the peripheral wall of the first cavity 21 and communicates with the first cavity 21, and the first valve port 24 is provided at the end of the first cavity 21 away from the second cavity 22. The medium can flow into the first cavity 21 through one of the first connecting hole 23 and the first valve port 24, and flow out through the other of the first connecting hole 23 and the first valve port 24.

[0072] Further, see attached document. Figure 3As shown, the second valve needle 3 is located inside the housing 2 and partially extends into the first cavity 21. The second valve needle 3 extends along the axial direction of the housing 2 and is movable along the axial direction of the housing 2 to open or close the first valve port 24. When the second valve needle 3 blocks the first valve port 24, the first connecting hole 23 and the first valve port 24 are no longer connected, the medium cannot flow into the first cavity 21 from the first valve port 24, and the medium in the first cavity 21 cannot flow out from the first valve port 24.

[0073] Furthermore, see the attached document. Figure 3 and attached Figure 9 As shown, the second valve needle 3 has a third cavity 31. The axial end face of the second valve needle 3 opposite to the second cavity 22 has a second valve port 32 communicating with the third cavity 31. The second valve port 32 is coaxially arranged with the first valve port 24. The peripheral wall of the second valve needle 3 has a second connecting hole 33 communicating with the third cavity 31 and the first cavity 21. The medium can enter the first cavity 21 through the first connecting hole 23 and flow into the third cavity 31 through the second connecting hole 33. Finally, it flows out of the electronic expansion valve 100 through the second valve port 32 and the first valve port 24 in sequence. Alternatively, the medium can enter the third cavity 31 through the first valve port 24 and the second valve port 32 in sequence, then flow out of the third cavity 31 through the second connecting hole 33 and enter the first cavity 21, and finally flow out of the electronic expansion valve 100 through the first connecting hole 23.

[0074] Furthermore, see the attached document. Figure 5 Appendix Figure 6 and attached Figure 7 As shown, the valve needle structure 1 passes through the second valve needle 3 and is movable along the axial direction of the housing 2. A portion of the first valve needle 14 is located within the third cavity 31 to open or close the second valve port 32. The axial direction of the guide sleeve 11 is the same as the axial direction of the housing 2. When the first valve needle 14 blocks the second valve port 32, the second connecting hole 33 and the second valve port 32 are no longer connected, and the medium cannot flow from the second valve port 32 into the third cavity 31, nor can the medium in the third cavity 31 flow out from the second valve port 32. It should be noted that the second valve needle 3 can guide the portion of the first valve needle 14 located outside the guide sleeve 11, thereby strengthening the guiding effect on the end of the first valve needle 14 near the second valve port 32 and improving the sealing performance of the first valve needle 14 for the second valve port 32.

[0075] It is understandable that by providing a second valve port 32 and a first valve needle 14 for blocking the second valve port 32 within the second valve needle 3, when the second valve needle 3 blocks the first valve port 24, the precise control of the electronic expansion valve 100 in the low flow stage can be achieved by adjusting the cooperation between the first valve needle 14 and the second valve port 32. This reduces flow lag during the switching process, reduces flow fluctuation, reduces leakage, and improves the performance of the electronic expansion valve 100. Furthermore, when the first valve needle 14 opens the second valve port 32 and the second valve needle 3 opens the first valve port 24, the opening degree of the electronic expansion valve 100 can be increased, reducing the impact of flow resistance on the system.

[0076] It should be noted that by setting the first valve needle 14 inside the second valve needle 3, the internal space of the electronic expansion valve 100 can be fully utilized, reducing the space occupied by the electronic expansion valve 100, shrinking the size of the electronic expansion valve 100, reducing the weight of the electronic expansion valve 100, and reducing the cost of the electronic expansion valve 100.

[0077] Further, see attached document. Figure 3 As shown, the drive assembly 4 is mounted on the housing 2 and is used to drive the screw 13 to move along the axial direction of the housing 2. The drive assembly 4 includes a coil component 41, a rotor component 42, a guide 43, and a nut 44. The coil component 41 is sleeved outside the housing 2, and the rotor component 42 is located inside the housing 2. The coil component 41 is located radially outside the rotor component 42 and is at least partially opposite to the rotor component 42, and is used to drive the rotor component 42 to rotate. The guide 43 is fixed inside the rotor component 42, and the nut 44 is fixed inside the housing 2. The screw 13 passes through the nut 44 and the guide 43 and its length direction (see attached figure) is [not specified]. Figure 3 One end of the rotor (in direction a) is welded to the guide 43, so that the rotor component 42, the guide 43 and the screw 13 rotate synchronously. Part of the screw 13 is threadedly connected to the nut 44. Since the screw 13 and the nut 44 form a threaded pair through threaded engagement, and the nut 44 is fixed inside the housing 2, the screw 13 needs to move along the axial direction of the housing 2 while rotating. The guide 43 and the rotor component 42 move along the axial direction of the housing 2 together with the screw 13.

[0078] It should be noted that by having the screw 13 pass through both the guide member 43 and the nut 44, and the guide member 43 and the nut 44 being spaced apart along the axial direction of the housing 2, the screw 13 can be prevented from deviating during rotation, thus ensuring the normal rotation of the screw 13.

[0079] It is understandable that, such as Figure 3As shown, when the coil component 41 is energized, the coil component 41 drives the rotor component 42 to rotate. Since the screw 13 is fixedly connected to the rotor component 42 through the guide 43, the rotor component 42 drives the screw 13 to rotate together. The screw 13 and the nut 44 are threaded together to form a threaded pair. The nut 44 is fixed on the housing 2, so that the screw 13 moves along the axial direction of the housing 2, thereby driving the rotor component 42 to move along the axial direction of the housing 2. During the process of the rotor component 42 moving along the axial direction of the housing 2, at least a part of the rotor component 42 is opposite to the coil component 41 to ensure that the coil component 41 drives the rotor component 42 to rotate normally.

[0080] In a further embodiment of this utility model, reference is made to the appendix. Figure 4 and attached Figure 8 As shown, a first flow channel 34 is provided on the end face of the second valve needle 3 facing away from the first valve port 24. A first limiting structure 341 is provided on the end of the first flow channel 34 away from the first valve port 24. The valve needle structure 1 passes through the first flow channel 34. A second limiting structure 112 is provided on the outer peripheral wall of the guide sleeve 11. The second limiting structure 112 is located on the side of the first limiting structure 341 close to the first valve port 24, and the second limiting structure 112 is adapted to abut against the surface of the first limiting structure 341 facing the first valve port 24. When the second limiting structure 112 abuts against the surface of the first limiting structure 341 facing the first valve port 24, the first valve needle 14 can drive the second valve needle 3 to move together in the direction away from the first valve port 24, thereby opening the first valve port 24. It should be noted that the opening limit of the first valve needle 14 can be adjusted by adjusting the matching distance between the second limiting structure 112 and the first limiting structure 341, thereby adjusting the flow curve of the electronic expansion valve 100.

[0081] In a specific example, see Appendix Figure 4 Appendix Figure 13 and attached Figure 14As shown, the first limiting structure 341 is an annular structure extending circumferentially along the second valve needle 3. The first limiting structure 341 is press-fitted with and welded to the inner wall of the first flow channel 34. The first valve needle 14 and the first limiting structure 341 are spaced apart radially. The second limiting structure 112 extends circumferentially along the first valve needle 14. The outer peripheral wall of the second limiting structure 112 has a notch 1121, which penetrates the second limiting structure 112 along the axial direction of the housing 2. It should be noted that there is a portion of the second limiting structure 112 without the notch 1121. There is a certain gap between the second valve needle 3 and the inner peripheral wall, which allows the medium to pass through. The notch 1121 can improve the efficiency of the medium flowing to the second cavity 22, ensure that the pressure in the second cavity 22 is consistent with that at the first valve port 24, and ensure that the electronic expansion valve 100 is always in a pressure balance state during the movement of the first valve needle 14 and the second valve needle 3. This avoids affecting the normal movement of the first valve needle 14 and the second valve needle 3 along the axial direction of the housing 2, and ensures the reliability and stability of the second valve needle 3 blocking the first valve port 24 and the first valve needle 14 blocking the second valve port 32.

[0082] Furthermore, the notches 1121 are multiple and spaced apart along the circumferential direction of the second limiting structure 112, which can further improve the efficiency of the medium flowing to the second cavity 22, ensure that the pressure at the second cavity 22 and the first valve port 24 is consistent, and ensure that the electronic expansion valve 100 is always in a pressure balance state during the movement of the first valve needle 14 and the second valve needle 3, so as to avoid affecting the normal movement of the first valve needle 14 and the second valve needle 3 along the axial direction of the housing 2, and ensure the reliability and stability of the second valve needle 3 blocking the first valve port 24 and the first valve needle 14 blocking the second valve port 32. For example, the notches 1121 can be two, three, four, five or six spaced apart along the circumferential direction of the second limiting structure 112.

[0083] Of course, this utility model is not limited to this. The second limiting structure 112 can also be a lug formed on the outer peripheral wall of the first valve needle 14, the first flow channel 34 is a guide groove that matches the lug and extends along the axial direction of the housing 2, and the first limiting structure 341 is a protrusion provided at one end of the guide groove away from the first valve port 24. It can also achieve the effect of the first valve needle 14 driving the second valve needle 3 to move together in the direction away from the first valve port 24 and opening the first valve port 24.

[0084] In a further embodiment of this utility model, reference is made to the appendix. Figure 11 and attached Figure 15As shown, the outer peripheral wall of the first valve needle 14 has a protrusion 141. One end of the first elastic member 15 away from the limiting member 111 abuts against the protrusion 141. The valve needle structure 1 also includes a second bushing 17. The first valve needle 14 passes through the second bushing 17. The second bushing 17 is located on the side of the protrusion 141 away from the first elastic member 15. The end face of the protrusion 141 facing the second bushing 17 is adapted to abut against the second bushing 17. The second bushing 17 can be used to prevent the first valve needle 14 from moving in the direction away from the screw 13, thereby preventing the first valve needle 14 from coming out of the guide sleeve 11.

[0085] Furthermore, when the first valve needle 14 closes the second valve port 32, the valve needle structure 1 has a first position and a second position. In the first position, such as... Figure 5 As shown, the protrusion 141 abuts against the second bushing 17, the first valve needle 14 is spaced apart from the screw 13, and the second limiting structure 112 is spaced apart from the inner wall of the first flow channel 34 near the first valve port 24. In the second position, as... Figure 4 As shown, the protrusion 141 is spaced apart from the second bushing 17.

[0086] It is understandable that by limiting the first valve needle 14 to be spaced apart from the screw 13 in the axial direction of the guide sleeve 11 when the first valve needle 14 changes from the first position to the second position, a gap can be maintained between the first valve needle 14 and the guide sleeve 11 to allow the screw 13 to move relative to the first valve needle 14 toward the direction closer to the second valve port 32; by limiting the second limiting structure 112 to be spaced apart from the inner wall of the first flow channel 34 near the first valve port 24 when the first position, a gap can be maintained to allow the screw 13 to move relative to the first valve needle 14 toward the direction closer to the second valve port 32 when the first valve needle 14 changes from the first position to the second position. When the first valve needle 14 is blocked, a certain space is left between the second limiting structure 112 and the inner wall of the first flow channel 34 near the first valve port 24, so that the guide sleeve 11 can move relative to the first valve needle 14 toward the direction of the second valve port 32. This allows the guide sleeve 11, bearing 12 and screw 13 to continue to move toward the direction of the second valve port 32 when the first valve needle 14 blocks the second valve port 32, compressing the first elastic element 15 and further ensuring the sealing of the first valve needle 14 to the second valve port 32, thereby making the protrusion 141 spaced apart from the second bushing 17.

[0087] In a further embodiment of this utility model, reference is made to the appendix. Figure 3As shown, the second valve needle 3 has a second flow channel 35, which extends along the axial direction of the housing 2. The second flow channel 35 is connected to the first valve port 24, and the second flow channel 35 is spaced apart from the third cavity 31 and the second connecting hole 33. The guide sleeve 11 has a third flow channel 113 and a balance hole 114. The bearing 12, the first elastic element 15, part of the screw 13 and part of the first valve needle 14 are all disposed in the third flow channel 113. The third flow channel 113 is connected to the end of the second flow channel 35 that is away from the first valve port 24. The balance hole 114 is disposed on the outer peripheral wall of the guide sleeve 11 and is used to connect the third flow channel 113 and the second cavity 22.

[0088] Understandably, the medium can enter the second flow channel 35 from the first valve port 24, then enter the third flow channel 113 from the second flow channel 35, and then flow into the second cavity 22 through the balance hole 114. This ensures that the pressure in the second cavity 22 is consistent with that at the first valve port 24, guaranteeing that the electronic expansion valve 100 remains in a pressure balance state during the movement of the first valve needle 14 and the second valve needle 3. This avoids affecting the normal movement of the first valve needle 14 and the second valve needle 3 along the axial direction of the housing 2, and ensures the reliability and stability of the second valve needle 3 blocking the first valve port 24 and the first valve needle 14 blocking the second valve port 32.

[0089] Furthermore, the arrangement of the third flow channel 113 and the balance hole 114 can connect the interior of the valve needle structure 1 with the exterior of the valve needle structure 1, so that the pressure of the third flow channel 113 and the exterior of the valve needle structure 1 remains consistent. This ensures that the valve needle structure 1 is always in a pressure balance state during the relative movement between the first valve needle 14 and the guide sleeve 11, avoiding affecting the relative movement between the first valve needle 14 and the guide sleeve 11, and ensuring the sealing reliability and stability of the valve needle structure 1.

[0090] It should be noted that, as Figure 3 As shown, by separating the second flow channel 35 from the third cavity 31 and the second connecting hole 33, it is possible to prevent the second flow channel 35 from communicating with the second connecting hole 33 or the third cavity 31 within the second valve needle 3. This prevents the medium from entering the second connecting hole 33 or the third cavity 31 through the second flow channel 35 when the second valve needle 3 blocks the first valve port 24 and the first valve needle 14 blocks the second valve port 32, thereby causing the first valve needle 14 to fail in blocking the second valve port 32.

[0091] It should be noted that the reference appendix Figure 4As shown, a sealing gasket 241 is provided inside the first valve port 24. The sealing gasket 241 extends in an annular shape along the circumferential direction of the first valve port 24. The second valve needle 3 is adapted to abut against the sealing gasket 241 to block the first valve port 24. Through the cooperation of the sealing gasket 241 and the second valve needle 3, the sealing effect of the second valve needle 3 on the first valve port 24 can be improved, ensuring the reliability of the second valve needle 3 in blocking the first valve port 24, and preventing the inflow or outflow of the medium when the second valve needle 3 blocks the first valve port 24.

[0092] Furthermore, the sealing gasket 241 is a plastic part, which has good elasticity, light weight, good corrosion resistance, good wear resistance, high strength, and low cost. Specifically, PTFE (polytetrafluoroethylene), PPS (polyphenylene sulfide), PEI (polyethyleneimine), or HNBR (hydrogenated nitrile butadiene rubber) are preferred. Alternatively, the sealing gasket 241 can be obtained by adding carbon fiber, glass fiber, carbon powder, etc. to the above materials, which can further improve the structural strength and hardness of the sealing gasket 241.

[0093] Of course, this utility model is not limited to this. When the limiting member 111 is a partition integrally formed in the guide sleeve 11, the balance hole 114 is located on the side of the limiting member 111 facing the first valve needle 14, which can ensure the communication between the inside and outside of the guide sleeve 11 and avoid affecting the relative movement between the first valve needle 14 and the guide sleeve 11.

[0094] In a further embodiment of this utility model, reference is made to the appendix. Figure 4 As shown, the electronic expansion valve 100 also includes a second elastic element 5, which is disposed within the second cavity 22 and is used to drive the second valve needle 3 to move toward the first valve port 24. It can be understood that the length direction of the second elastic element 5 (see attached diagram) Figure 4 (Direction a) shown is the axial direction of the housing 2. The two ends of the second elastic element 5 in the length direction abut against the nut 44 and the second valve needle 3 respectively, which can ensure that the contact area at both ends of the second elastic element 5 in the length direction is sufficient, and ensure the reliability of the assembly of the second elastic element 5. The second elastic element 5 is always in a compressed state, which can provide a driving force to the second valve needle 3, driving the second valve needle 3 to move towards the direction close to the first valve port 24, which can ensure the sealing effect of the second valve needle 3 on the first valve port 24 when the second valve needle 3 blocks the first valve port 24.

[0095] In some other embodiments of this utility model, the electronic expansion valve 100 further includes a housing 2 and a drive assembly 4. The housing 2 can protect the internal structure of the electronic expansion valve 100, which is beneficial to extending the service life of the electronic expansion valve 100. The housing 2 has a first cavity 21, a second cavity 22, a first connecting hole 23 and a first valve port 24. The first cavity 21 and the second cavity 22 are arranged in the axial direction of the housing 2. The first connecting hole 23 is provided on the peripheral wall of the first cavity 21 and communicates with the first cavity 21. The first valve port 24 is provided at the end of the first cavity 21 away from the second cavity 22. The medium can flow into the first cavity 21 through one of the first connecting hole 23 and the first valve port 24, and flow out through the other of the first connecting hole 23 and the first valve port 24.

[0096] Furthermore, the valve needle structure 1 is disposed inside the housing 2, and part of the first valve needle 14 extends into the first cavity 21 for opening or closing the first valve port 24. The axial direction of the guide sleeve 11 is the same as the axial direction of the housing 2. When the first valve needle 14 closes the first valve port 24, the first connecting hole 23 and the first valve port 24 are no longer connected, the medium cannot flow into the first cavity 21 from the first valve port 24, and the medium in the first cavity 21 cannot flow out from the first valve port 24. The drive assembly 4 is disposed on the housing 2 for driving the screw 13 to move along the axial direction of the housing 2.

[0097] Under the drive of the drive assembly 4, the screw 13 drives the first valve needle 14 to move along the axial direction of the housing 2. When the first valve needle 14 opens the first valve port 24, the medium can flow into the first cavity 21 from one of the first valve port 24 and the first connecting hole 23, and then flow from the first cavity 21 to the other of the first valve port 24 and the first connecting hole 23. When the first valve needle 14 closes the first valve port 24, the medium in the first cavity 21 cannot flow out from the first valve port 24, and the medium outside the electronic expansion valve 100 cannot flow into the first cavity 21 from the first valve port 24. By opening or closing the first valve port 24, different user needs can be met and the user experience can be improved.

[0098] It is understandable that, such as Figure 3 As shown, when the electronic expansion valve 100 includes the valve needle structure 1 and the second valve needle 3, the process of the electronic expansion valve 100 gradually opening (as shown) Figures 4 to 9As shown): The screw 13 drives the guide sleeve 11 to move in a direction away from the second valve port 32. The first elastic element 15 gradually resets, absorbing the gap between the protrusion 141 and the second bushing 17 until the protrusion 141 abuts against the second bushing 17. The valve core structure changes from the second position to the first position. Then the screw 13 continues to move in a direction away from the second valve port 32, driving the first valve needle 14 to move in a direction away from the second valve port 32, slowly opening the second valve port 32. At this time, the medium can enter the first cavity 21 through the first connecting hole 23 and flow into the third cavity 31 through the second connecting hole 33, and then flow out of the first valve port 24 through the second valve port 32. Alternatively, the medium can pass through the first valve port 24 and the second valve port 32 in sequence to enter the third cavity 31, enter the first cavity 21 through the second connecting hole 33, and finally flow out through the first connecting hole 23.

[0099] The screw 13 continues to drive the first valve needle 14 to move away from the first valve port 24 until the surfaces of the second limiting structure 112 and the first limiting structure 341 facing the first valve port 24 stop. The screw 13 drives the first valve needle 14 and the second valve needle 3 to move together away from the first valve port 24 to open the first valve port 24. At this time, the first valve needle 14 and the second valve needle 3 will not move relative to each other in the axial direction of the housing 2, so that the first valve port 24 is fully opened. The medium can flow into the first cavity 21 through one of the first connecting hole 23 and the first valve port 24, and flow out through the other.

[0100] The process of the electronic expansion valve 100 gradually closing (e.g.) Figures 9 to 4 As shown): When the second valve needle 3 opens the first valve port 24, the first connecting hole 23 and the first valve port 24 are connected through the first cavity 21. The medium can flow into the first cavity 21 from one of the first connecting hole 23 and the first valve port 24 and flow out from the other. At this time, the surfaces of the second limiting structure 112 and the first limiting structure 341 facing the first valve port 24 stop; the screw 13 moves toward the direction close to the first valve port 24, and the screw 13 drives the first valve needle 14 and the second valve needle 3 to move toward the direction close to the first valve port 24. The second elastic element 5 gradually resets. At this time, the first valve needle 14 and the second valve needle 3 will not move relative to each other in the axial direction of the housing 2.

[0101] When the second valve needle 3 blocks the first valve port 24, the second valve needle 3 can no longer move toward the first valve port 24. The screw 13 continues to push the first valve needle 14 toward the direction closer to the second valve port 32. The second limiting structure 112 gradually separates from the first limiting structure 341. At this time, the medium can enter the first cavity 21 through the first connecting hole 23, flow into the third cavity 31 through the second connecting hole 33, and then flow out of the first valve port 24 through the second valve port 32. Alternatively, the medium can pass through the first valve port 24 and the second valve port in sequence. 32 enters the third cavity 31, enters the first cavity 21 through the second connecting hole 33, and finally flows out through the first connecting hole 23; when the first valve needle 14 blocks the second valve port 32, the second valve needle 3 can no longer move toward the second valve port 32, the screw 13 is over-tightened and compresses the first elastic element 15, so that the protrusion 141 is separated from the second bushing 17, 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 second valve port 32 when the power is off or when it is not running, thus avoiding medium leakage.

[0102] It is understandable that when the electronic expansion valve 100 only includes the valve needle structure 1, the process of the electronic expansion valve 100 gradually closing is as follows: the screw 13 moves toward the direction close to the first valve port 24. Since the first elastic element 15 is relatively hard, it will not be compressed at this time, so that the first valve needle 14 and the first elastic element 15 move together as a whole toward the direction close to the first valve port 24 until the second valve needle 3 blocks the first valve port 24. The second valve needle 3 can no longer move, but under the drive of the drive assembly 4, the screw 13 continues to rotate and move toward the direction close to the first valve port 24, compressing the first elastic element 15, 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 first valve port 24 when the power is off or when it is not running, thus avoiding media leakage.

[0103] The process of the electronic expansion valve 100 gradually opening: the screw 13 moves in the direction away from the first valve port 24, the first elastic element 15 gradually resets, and then the screw 13 continues to move in the direction away from the first valve port 24, driving the first valve needle 14 to move in the direction away from the first valve port 24, and the first valve port 24 opens. At this time, the medium can flow into the first cavity 21 through one of the first connecting hole 23 and the first valve port 24, and flow out through the other, thereby ensuring the reliability and stability of the second valve needle 3 sealing the first valve port 24, reducing the failure risk of the electronic expansion valve 100, and extending the service life of the electronic expansion valve 100.

[0104] 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.

[0105] 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.

[0106] 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 by, include: Guide sleeve (11), the inner peripheral wall of the guide sleeve (11) is provided with a limiting member (111), the limiting member (111) and the guide sleeve (11) are integral parts; The bearing (12) is disposed inside the guide sleeve (11) and the bearing (12) is located on one side of the limiting member (111) along the axial direction of the guide sleeve (11); A screw (13) is rotatably inserted into the guide sleeve (11) and extends along the axial direction of the guide sleeve (11). The screw (13) is inserted into the bearing (12). The first valve needle (14) is inserted into the guide sleeve (11) and extends along the axial direction of the guide sleeve (11). The first valve needle (14) is located on the side of the limiting member (111) away from the bearing (12). The first valve needle (14) is movable along the axial direction of the guide sleeve (11). The first elastic element (15) is disposed between the first valve needle (14) and the limiting element (111) for driving the first valve needle (14) to move in a direction away from the screw (13).

2. The valve needle structure of claim 1, wherein The first valve needle (14) has a protrusion (141) on its outer peripheral wall, and the end of the first elastic member (15) facing away from the limiting member (111) abuts against the protrusion (141). The valve needle structure (1) further includes: The first bushing (16) and the second bushing (17) are respectively disposed at the two ends of the guide sleeve (11). The screw (13) passes through the first bushing (16). The first bushing (16) is located on the side of the bearing (12) away from the limiting member (111) and is used to restrict the bearing (12) from moving in the direction away from the limiting member (111). The first valve needle (14) passes through the second bushing (17). The second bushing (17) is located on the side of the protrusion (141) away from the first elastic member (15).

3. The valve needle structure of claim 1, wherein The limiting member (111) has a limiting boss on the side facing the first valve needle (14), and the first elastic member (15) is sleeved on the limiting boss. And / or, the limiting member (111) has a limiting groove on the side opposite to the first valve needle (14), the outer ring of the bearing (12) is located outside the limiting groove, and the inner ring of the bearing (12) is located inside the limiting groove.

4. The valve needle structure of claim 1, wherein The first valve needle (14) has a sealing section (142) at the end opposite to the screw (13), and the cross-sectional area of ​​the sealing section (142) gradually decreases in the direction from the screw (13) to the first valve needle (14).

5. An electronic expansion valve characterized by, Includes the valve needle structure (1) according to any one of claims 1-4.

6. The electronic expansion valve according to claim 5, wherein Also includes: The housing (2) has a first cavity (21), a second cavity (22), a first connecting hole (23) and a first valve port (24). The first cavity (21) and the second cavity (22) are arranged in the axial direction of the housing (2). The first connecting hole (23) is provided on the peripheral wall of the first cavity (21) and communicates with the first cavity (21). The first valve port (24) is provided at the end of the first cavity (21) away from the second cavity (22). The second valve needle (3) is located inside the housing (2) and partially extends into the first cavity (21). The second valve needle (3) is movable along the axial direction of the housing (2) to open or close the first valve port (24). The second valve needle (3) has a third cavity (31). The second valve needle (3) has a second valve port (32) communicating with the third cavity (31) on its axial end face away from the second cavity (22). The peripheral wall of the second valve needle (3) has a second communicating hole (33) communicating with the third cavity (31) and the first cavity (21). The valve needle structure (1) is inserted inside the second valve needle (3) and is movable along the axial direction of the housing (2). Part of the first valve needle (14) is located inside the third cavity (31) to open or close the second valve port (32). The axial direction of the guide sleeve (11) is the same as the axial direction of the housing (2). A drive assembly (4) is disposed on the housing (2) and is used to drive the screw (13) to move along the axial direction of the housing (2).

7. The electronic expansion valve according to claim 6, wherein The second valve needle (3) has a first flow channel (34) on the end face away from the first valve port (24). The end of the first flow channel (34) away from the first valve port (24) has a first limiting structure (341). The valve needle structure (1) passes through the first flow channel (34). The outer peripheral wall of the guide sleeve (11) has a second limiting structure (112). The second limiting structure (112) is located on the side of the first limiting structure (341) close to the first valve port (24), and the second limiting structure (112) is adapted to abut against the surface of the first limiting structure (341) facing the first valve port (24).

8. The electronic expansion valve according to claim 7, characterized in that The first valve needle (14) has a protrusion (141) on its outer peripheral wall. The end of the first elastic member (15) facing away from the limiting member (111) abuts against the protrusion (141). The valve needle structure (1) also includes a second bushing (17). The first valve needle (14) passes through the second bushing (17). The second bushing (17) is located on the side of the protrusion (141) facing away from the first elastic member (15). When the first valve needle (14) closes the second valve port (32), the valve needle structure (1) has a first position and a second position. In the first position, the protrusion (141) abuts against the second bushing (17), the first valve needle (14) is spaced apart from the screw (13), and the second limiting structure (112) is spaced apart from the inner wall of the first flow channel (34) near the first valve port (24). In the second position, the protrusion (141) is spaced apart from the second bushing (17).

9. The electronic expansion valve according to claim 6, wherein The second valve needle (3) has a second flow channel (35), which is connected to the first valve port (24). The second flow channel (35) is spaced apart from the third cavity (31) and the second connecting hole (33). The guide sleeve (11) has a third flow channel (113) and a balance hole (114). The bearing (12), the first elastic element (15), part of the screw (13) and part of the first valve needle (14) are all located in the third flow channel (113). The third flow channel (113) is connected to the end of the second flow channel (35) that is away from the first valve port (24). The balance hole (114) is located on the outer peripheral wall of the guide sleeve (11) and is used to connect the third flow channel (113) and the second cavity (22).

10. The electronic expansion valve according to claim 5, wherein Also includes: The housing (2) has a first cavity (21), a second cavity (22), a first connecting hole (23), and a first valve port (24). The first cavity (21) and the second cavity (22) are arranged in the axial direction of the housing (2). The first connecting hole (23) is provided on the peripheral wall of the first cavity (21) and communicates with the first cavity (21). The first valve port (24) is provided at one end of the first cavity (21) away from the second cavity (22). The valve needle structure (1) is provided in the housing (2), and part of the first valve needle (14) extends into the first cavity (21) for opening or closing the first valve port (24). The axial direction of the guide sleeve (11) is the same as the axial direction of the housing (2). A drive assembly (4) is disposed on the housing (2) and is used to drive the screw (13) to move along the axial direction of the housing (2).

Images