Electronic expansion valve

Abstract

The utility model provides an electronic expansion valve which comprises a valve seat assembly, a valve element assembly and a driving assembly. The valve seat assembly is provided with a first valve port, a first valve hole and a second valve hole closer to the first valve port. The valve element assembly comprises a first valve needle and a second valve needle. The first valve needle is in sealing fit with the first valve port and is internally provided with a fluid passage; the fluid passage is provided with a second valve port, one end of the fluid passage communicates with the first valve hole, and the other end communicates with the first valve port; the transverse channel is opened on the side surface of the first valve needle; the longitudinal channel penetrates in the axial direction; the second valve port communicates with the other end of the first valve needle and the transverse channel. The second valve needle is in sealing fit with the second valve port; the driving assembly is used for driving the first valve needle and the second valve needle to move in the axial direction so as to control the first valve port and the second valve port.

Description

Technical Field

[0001] This disclosure relates to the field of valve technology, and more particularly to an electronic expansion valve. Background Technology

[0002] Electronic expansion valves, as throttling elements, are used to regulate the flow and control of fluids. In existing designs, electronic expansion valves include a valve seat with two valve ports (upper and lower) inside the valve chamber. These two ports cannot be closed simultaneously, which fails to meet customer requirements.

[0003] Therefore, how to achieve simultaneous closure of the upper and lower valve ports of an electronic expansion valve has become an important issue that urgently needs to be addressed in related fields. Summary of the Invention

[0004] A primary objective of this disclosure is to overcome at least one of the deficiencies of the prior art described above and to provide an electronic expansion valve.

[0005] To achieve the above objectives, the present disclosure adopts the following technical solution:

[0006] According to one aspect of this disclosure, an electronic expansion valve is provided, which includes a valve seat assembly, a valve core assembly, and a drive assembly;

[0007] The valve seat assembly has a valve cavity inside, and the valve seat assembly has a first valve port, a first valve hole, and a second valve hole closer to the first valve port than the first valve hole; the valve core assembly includes a first valve needle and a second valve needle; the first valve needle is disposed in the valve cavity; one end of the first valve needle is sealed to the first valve port; the first valve needle has a fluid passage inside; the fluid passage has a second valve port, one end of the fluid passage is connected to the first valve hole, and the other end is connected to the first valve port; the second valve needle is disposed in the valve cavity; the end of the second valve needle facing the first valve port is sealed to the second valve port; The driving assembly is used to drive the first valve needle and the second valve needle to move axially, so as to realize the opening and closing control of the first valve port and the second valve port; wherein, when the first valve port is closed and the second valve port is open, the first valve port is isolated from the second valve orifice, and the first valve orifice is connected to the first valve port through the fluid passage; when the first valve port is open and the second valve port is closed, the second valve orifice is connected to the first valve port, and the first valve port is disconnected from the first valve orifice; when the first valve port is closed and the second valve port is closed, the second valve orifice is disconnected from the first valve port, and the first valve port is disconnected from the first valve orifice.

[0008] According to one embodiment of this disclosure, the fluid passage includes a transverse channel, a longitudinal channel, and a valve port channel disposed inside a first valve needle; a second valve port is located in the valve port channel; at least one end of the transverse channel opens onto the side of the first valve needle; the longitudinal channel extends axially through the first valve needle; the valve port channel connects the end of the first valve needle facing away from the first valve port with the transverse channel; the end of the first valve needle facing away from the first valve port communicates with the first valve port through the longitudinal channel; the first valve needle includes a body portion and an extension portion; the body portion is disposed in the valve cavity and has the transverse channel and the valve port channel disposed thereon; one end of the extension portion is connected to the body portion, and the other end is provided with a sealing structure, which seals the first valve port when the first valve port is closed; wherein, the body portion has a first sub-channel extending axially, and the extension portion has a second sub-channel extending axially, the first sub-channel and the second sub-channel communicating to form the longitudinal channel.

[0009] According to one embodiment of this disclosure, the valve port passage does not penetrate the body portion.

[0010] According to one embodiment of this disclosure, the outer wall surface of the extension is provided with an annular groove, wherein the groove depth at both ends along the axial direction is less than the groove depth at the middle of the groove.

[0011] According to one embodiment of this disclosure, the main body is provided with at least two first sub-channels; the end of the second sub-channel near the main body is provided with an open structure, the inner diameter of the open structure is larger than the inner diameter of the second sub-channel, and the second sub-channel communicates with at least two first sub-channels simultaneously through the open structure.

[0012] According to one embodiment of this disclosure, a first groove is provided on the end face of the main body facing the extension, and the end face of the extension facing the main body is connected to the main body; a first sub-channel opens at the bottom of the first groove, and a second sub-channel opens at the end face of the extension facing the main body; the distance between the bottom of the first groove and the end face of the main body is greater than or equal to zero.

[0013] According to one embodiment of this disclosure, the extension has a protrusion on its end face facing the body portion, and the protrusion is received in the first groove; the second sub-channel opens at the end face of the protrusion facing the body portion.

[0014] According to one embodiment of this disclosure, the end of the first valve needle facing away from the second valve needle extends out of the first valve port and is provided with a sealing structure. When the first valve port is closed, the sealing structure seals the side of the first valve port facing away from the second valve port. The first valve needle is provided with a flow regulating section, which is adjacent to the sealing structure on the side near the first valve port. The outer periphery of the flow regulating section is a flow regulating slope, so that the outer diameter of the flow regulating section gradually decreases in the axial direction away from the sealing structure.

[0015] According to one embodiment of this disclosure, a first sealing ring and a second sealing ring are provided between the first valve needle and the valve seat assembly; the first sealing ring is located on the side of the first valve hole away from the second valve hole, and the second sealing ring is located between the first valve hole and the second valve hole.

[0016] According to one embodiment of this disclosure, the electronic expansion valve further includes a first elastic element; the first elastic element is located within the valve cavity, and the first elastic element is used to provide a preload force when the first valve needle closes the first valve port; one end of the first valve needle is sealed to the first valve port, and the other end of the first valve needle is provided with a first limiting plate, the first limiting plate extending radially away from the first valve needle, and the first elastic element is located between the first limiting plate and the inner wall of the valve cavity.

[0017] According to one embodiment of the present disclosure, the valve seat assembly includes a first valve seat and a second valve seat, at least a portion of the second valve seat extends into the first valve seat, the first valve needle moves axially relative to the inner wall of the second valve seat, and the first elastic member is located in the gap between the portion of the second valve seat extending into the first valve seat and the first valve seat.

[0018] According to one embodiment of this disclosure, the electronic expansion valve further includes a second elastic element; the second elastic element is used to provide a preload force when the second valve needle closes the second valve port; the drive assembly includes a valve stem that is axially movable and used to push and pull the second valve needle axially; a pressure sleeve is connected to the end of the second valve needle facing the valve stem, the pressure sleeve and the second valve needle together forming a receiving cavity; the end of the valve stem facing the second valve needle extends into the receiving cavity and is provided with a limiting portion, the limiting portion being limited and engaged with the pressure sleeve; the second elastic element is located in the receiving cavity and connects the limiting portion and the second valve needle.

[0019] According to one embodiment of this disclosure, a T-shaped bushing is further provided in the receiving cavity, the top surface of the bushing is in contact with the limiting portion, the second elastic element is sleeved on the bushing and located between the bushing and the second valve needle, and the maximum distance between the bottom surface of the bushing and the second valve needle is the maximum distance that the valve stem can move relative to the second valve needle.

[0020] According to one embodiment of this disclosure, the electronic expansion valve further includes a third elastic element located within the valve cavity, and a second limiting plate is provided at the other end of the first valve needle. The second limiting plate extends radially close to the first valve needle, and the third elastic element is located between the second limiting plate and the second valve needle.

[0021] According to one embodiment of this disclosure, the drive assembly includes a valve stem that is axially movable and used to push and pull the second valve needle axially; the interior of the second valve needle is a receiving cavity; the end of the valve stem extending toward the second valve needle extends into the receiving cavity and is provided with a limiting portion, the limiting portion being limited and engaged with a pressure plate at the opening of the receiving cavity; the second valve needle is provided with a second sealing structure that seals with the second valve port.

[0022] According to one embodiment of this disclosure, a second groove is provided on the end face of the first valve needle facing the second valve needle, and the second valve needle is partially accommodated in the second groove; the longitudinal channel opens at the bottom of the second groove; wherein, a baffle is provided at the opening of the second groove for the first valve needle, the baffle including an integrally formed first stop portion and a second stop portion, the first stop portion extending radially away from the first valve needle, and the second stop portion extending radially to the opening of the second groove.

[0023] According to one embodiment of this disclosure, the baffle is connected to the first valve needle via a through-welding process.

[0024] According to one embodiment of this disclosure, the surface of the baffle facing away from the first valve needle is provided with a stepped structure, such that the surface of the baffle forms a first stepped surface located in the outer ring in the radial direction and a second stepped surface located in the inner ring, the first stepped surface being axially farther away from the first valve needle than the second stepped surface, and the second stepped surface being directly opposite the outer edge of the groove of the second groove.

[0025] As can be seen from the above technical solution, the advantages and positive effects of the electronic expansion valve proposed in this disclosure are as follows:

[0026] The electronic expansion valve disclosed herein includes a valve seat assembly, a valve core assembly, and a drive assembly. The valve seat assembly has a first valve port, a first valve bore, and a second valve bore closer to the first valve port. The valve core assembly includes a first valve needle and a second valve needle. The first valve needle is sealed to the first valve port and has a fluid passage inside. The fluid passage has a second valve port, one end of which communicates with the first valve bore, and the other end of which communicates with the first valve port. A transverse channel opens on the side of the first valve needle. A longitudinal channel extends axially through the valve. The second valve port connects the other end of the first valve needle to the transverse channel. The system includes a channel; a second valve needle that seals with the second valve port; and a drive assembly for driving the first and second valve needles to move axially to control the first and second valve ports. When the first valve port is closed and the second valve port is open, the first valve port is isolated from the second valve port, and the first valve port is connected to the first valve port via a fluid passage. When the first valve port is open and the second valve port is closed, the second valve port is connected to the first valve port, and the first valve port is disconnected from the first valve port. When the first valve port is closed and the second valve port is closed, the second valve port is disconnected from the first valve port, and the first valve port is disconnected from the first valve port. Through the above design, this disclosure can achieve simultaneous closure of the first and second valve ports, and also achieve communication between the first valve port and the second valve port, as well as communication between the longitudinal channel and the first valve port. Based on this, the electronic expansion valve proposed in this disclosure avoids setting complex channels on the valve seat assembly to connect the second valve port, which simplifies the product structure and reduces the difficulty and cost of manufacturing. Attached Figure Description

[0027] The various objectives, features, and advantages of this disclosure will become more apparent from the following detailed description of preferred embodiments of the disclosure taken in conjunction with the accompanying drawings. The drawings are merely illustrative illustrations of the disclosure and are not necessarily drawn to scale. In the drawings, the same reference numerals always denote the same or similar parts. Wherein:

[0028] Figure 1 This is a schematic diagram of the structure of an electronic expansion valve according to an exemplary embodiment;

[0029] Figure 2 yes Figure 1 Axonal sectional view of the electronic expansion valve is shown;

[0030] Figure 3 yes Figure 2 An enlarged schematic diagram of part of the structure is shown;

[0031] Figure 4 yes Figure 1 The diagram shows an axonal sectional view of the electronic expansion valve in another operating state.

[0032] Figure 5 yes Figure 4 An enlarged schematic diagram of part of the structure is shown;

[0033] Figure 6 yes Figure 1 The image shows an axonometric sectional view of the electronic expansion valve in yet another operating state;

[0034] Figure 7 This is an axial sectional view of an electronic expansion valve according to another exemplary embodiment;

[0035] Figure 8 yes Figure 7 An enlarged schematic diagram of part A in the diagram;

[0036] Figure 9 This is an axial sectional view of an electronic expansion valve according to yet another exemplary embodiment;

[0037] Figure 10 yes Figure 9 An enlarged schematic diagram of part B in the diagram;

[0038] Figure 11 This is an axial sectional view of an electronic expansion valve according to yet another exemplary embodiment;

[0039] Figure 12 yes Figure 11 An enlarged schematic diagram of part C in the diagram;

[0040] Figure 13 This is an axial sectional view of an electronic expansion valve according to another exemplary embodiment;

[0041] Figure 14 yes Figure 13 An enlarged schematic diagram of part E in the diagram;

[0042] Figure 15 yes Figure 14 The diagram shows the structure of the baffle.

[0043] The annotations in the attached figures are explained as follows:

[0044] 100. Valve seat assembly;

[0045] 101. Valve chamber;

[0046] 102. First valve port;

[0047] 103. First valve orifice;

[0048] 104. Second valve hole;

[0049] 110. First valve seat;

[0050] 120. Second valve seat;

[0051] 200. Valve core assembly;

[0052] 210. First valve needle;

[0053] 2101. Horizontal passageway;

[0054] 2102. Longitudinal channel;

[0055] 2103. Second valve port;

[0056] 2104. Flow regulating ramp;

[0057] 211. Ontology part;

[0058] 2111. First sub-channel;

[0059] 2113. Second groove;

[0060] 212. Extension;

[0061] 2121. Second sub-channel;

[0062] 21211. Open structure;

[0063] 213. First sealing structure;

[0064] 214. Baffle;

[0065] 2141. First stop part;

[0066] 2142. Second stop;

[0067] 2143. Stepped structure;

[0068] 21431. First step surface;

[0069] 21432. Second step surface;

[0070] 215. First limiting plate;

[0071] 216. Second limiting plate;

[0072] 220. Second valve needle;

[0073] 221. Second sealing structure;

[0074] 222. Pressure sleeve;

[0075] 2221. Receiving cavity;

[0076] 230. First sealing ring;

[0077] 240. Second sealing ring;

[0078] 300. Driver components;

[0079] 310. Valve stem;

[0080] 311. Limiting part;

[0081] 312. Bushing;

[0082] 410. First elastic element;

[0083] 420. Second elastic element;

[0084] 430. Third elastic element;

[0085] α. Angle;

[0086] d1. Distance;

[0087] d2. Length;

[0088] h. Maximum distance;

[0089] G1. First gap;

[0090] G2. Second gap;

[0091] G3. Third gap. Detailed Implementation

[0092] Typical embodiments embodying the features and advantages of this disclosure will be described in detail in the following description. It should be understood that this disclosure can have various variations in different embodiments without departing from the scope of this disclosure, and the descriptions and drawings therein are illustrative in nature and not intended to limit this disclosure.

[0093] In the following description of various exemplary embodiments of this disclosure, reference is made to the accompanying drawings, which form part of this disclosure, and which illustrate by way of example different exemplary structures, systems, and steps that can implement various aspects of this disclosure. It should be understood that other specific embodiments of the components, structures, exemplary devices, systems, and steps may be used, and structural and functional modifications may be made without departing from the scope of this disclosure. Furthermore, while the terms “above,” “between,” “within,” etc., may be used in this specification to describe different exemplary features and elements of this disclosure, these terms are used herein only for convenience, such as the orientation according to the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional orientation of the structure to fall within the scope of this disclosure.

[0094] See Figure 1 The illustration shows a representative structural diagram of the electronic expansion valve proposed in this disclosure. In this exemplary embodiment, the electronic expansion valve proposed in this disclosure is described using a valve applied to a refrigeration system as an example. It will be readily understood by those skilled in the art that various modifications, additions, substitutions, deletions, or other changes may be made to the specific embodiments described below in order to apply the relevant designs of this disclosure to other application scenarios, and these changes are still within the scope of the principle of the electronic expansion valve proposed in this disclosure.

[0095] In one embodiment of this disclosure, the electronic expansion valve includes a valve seat assembly 100, a valve core assembly 200, and a drive assembly 300. (See also...) Figures 2 to 6 , Figure 2 The image shows a representative axial sectional view of the electronic expansion valve. Figure 3 China representatively shows Figure 2 The enlarged schematic diagram of a portion of the structure shown specifically illustrates the combined structure of the second valve needle 220, the pressure sleeve 222, a portion of the valve stem 310, and the second elastic element 420. Figure 4 The image shows a representative axial sectional view of the electronic expansion valve in another operating state; Figure 5 China representatively shows Figure 4 The enlarged schematic diagram of a portion of the structure shown specifically illustrates the combined structure of the second valve needle 220, the pressure sleeve 222, a portion of the valve stem 310, and the second elastic element 420. Figure 6 The figure shows a representative axial sectional view of the electronic expansion valve in another operating state. The structure, connection method, and functional relationship of the main components of the electronic expansion valve proposed in this disclosure will be described in detail below with reference to the above figures.

[0096] like Figures 1 to 6As shown, in one embodiment of this disclosure, the valve seat assembly 100 has a valve cavity 101 inside. The valve seat assembly 100 has a first valve port 102, a first valve hole 103, and a second valve hole 104. The first valve port 102 is, for example, located at one end of the valve seat assembly 100 in the axial direction (e.g., the lower end shown in the figure). The first valve hole 103 is, for example, located on the side of the valve seat assembly 100, and the second valve hole 104 is closer to the first valve port 102 than the first valve hole 103. The valve core assembly 200 includes a first valve needle 210 and a second valve needle 220. The first valve needle 210 is disposed in the valve cavity 101. One end of the first valve needle 210 is sealed to the first valve port 102 (e.g., sealed by a first sealing structure 213 provided on the first valve needle 210). The first valve needle 210 has a fluid passage inside, and the fluid passage has a second valve port 2103. One end of the fluid passage communicates with the first valve hole 103, and the other end of the fluid passage communicates with the first valve port 102. The second valve needle 220 is disposed in the valve cavity 101. The end of the second valve needle 220 facing the first valve port 102 is sealed to the second valve port 2103 (for example, through a second sealing structure 221 provided on the second valve needle 220). The drive assembly 300 is used to drive the first valve needle 210 and the second valve needle 220 to move axially, so as to control the opening and closing of the first valve port 102 and the second valve port 2103. Accordingly, when the first valve port 102 is closed and the second valve port 2103 is open, the first valve port 102 is isolated from the second valve hole 104, and the first valve hole 103 is connected to the first valve port 102 via a fluid passage. When the first valve port 102 is open and the second valve port 2103 is closed, the second valve hole 104 is connected to the first valve port 102, and the first valve port 102 is disconnected from the first valve hole 103. When the first valve port 102 is closed and the second valve port 2103 is closed, the second valve hole 104 is disconnected from the first valve port 102, and the first valve port 102 is disconnected from the first valve hole 103. For example, the drive assembly 300 may include a valve stem 310 that moves axially. When the valve stem 310 moves toward the first valve port 102, it can push the second valve needle 220 toward the first valve port 102 (i.e., toward the first valve needle 210). When the second valve needle 220 closes the second valve port 2103, the valve stem 310 further pushes the second valve needle 220 toward the first valve port 102, thereby simultaneously causing the first valve needle 210 to move toward the first valve port 102. This achieves the first valve needle 210 opening the first valve port 102, i.e., the first valve port 102 is open and the second valve port 2103 is closed. Furthermore, when the valve stem 310 moves away from the first valve port 102, the valve stem 310 can pull the second valve needle 220 to move away from the first valve port 102 (i.e., move away from the first valve needle 210). Specifically, this can be achieved, for example, through the cooperation between the limiting part 311 of the valve stem 310 and the pressure sleeve 222, thereby realizing the opening of the second valve port 2103 and the closing of the first valve port 102.Based on this, when the first valve port 102 is closed and the second valve port 2103 is open, the valve stem 310 pushes the second valve needle 220 to close the second valve port 2103 and stops moving, thus achieving simultaneous closure of the first valve port 102 and the second valve port 2103. Through the above design, this disclosure can achieve simultaneous closure of the first valve port 102 and the second valve port 2103. Furthermore, it can also achieve communication between the first valve port 102 and the second valve hole 104, and between the longitudinal channel 2102 and the first valve hole 103. Based on this, the electronic expansion valve proposed in this disclosure avoids setting complex channels on the valve seat assembly 100 to connect the second valve port 2103, simplifying the product structure and reducing manufacturing difficulty and cost.

[0097] like Figure 1 , Figure 2 , Figure 4 and Figure 6 As shown, in one embodiment of this disclosure, the end of the first valve needle 210 facing away from the second valve needle 220 extends into a first valve port 102 and is provided with a sealing structure, such as the first sealing structure 213 shown in the figure. Accordingly, when the first valve port 102 is closed, the first sealing structure 213 seals the side of the first valve port 102 facing away from the second valve port 2103. It should be noted that the sealing structure can be made of metal itself, or it can be a soft material structure with a lower hardness than the first valve port 102 provided on the extension 212.

[0098] like Figure 2 , Figure 4 and Figure 6As shown, in one embodiment of this disclosure, the fluid passage includes a transverse channel 2101, a longitudinal channel 2102, and a valve port channel disposed inside the first valve needle 210. A second valve port 2103 is located in the valve port channel. At least one end of the transverse channel 2101 opens onto the side of the first valve needle 210. The longitudinal channel 2102 extends axially through the first valve needle 210. The valve port channel connects the end of the first valve needle 210 facing away from the first valve port 102 with the transverse channel 2101. The end of the first valve needle 210 facing away from the first valve port 102 is connected to the first valve port 102 via the longitudinal channel 2102. Based on this, the first valve needle 210 may include a body portion 211 and an extension portion 212. The body portion 211 is disposed in the valve cavity 101 of the valve seat assembly 100, and the body portion 211 is provided with the transverse channel 2101 and the valve port channel. One end of the extension 212 is connected to the main body 211, and the other end of the extension 212 is provided with a sealing structure (such as the first sealing structure 213 mentioned above). When the first valve port 102 is closed, the sealing structure provided in the extension 212 seals the first valve port 102. Based on this, the main body 211 may be provided with a first sub-channel 2111 that extends through the axial direction, and the extension 212 may be provided with a second sub-channel 2121 that extends through the axial direction. The first sub-channel 2111 and the second sub-channel 2121 communicate to form a longitudinal channel 2102 of the first valve needle 210.

[0099] As stated above, the working principle of the electronic expansion valve disclosed herein includes: (See attached document) Figure 2 When the electronic expansion valve is in the upper stop position, throttling occurs between the longitudinal channel 2102 and the first valve port 103, and the connection between the first valve port 102 and the second valve port 104 is broken. As the valve stem 310 moves downward, the connection between the longitudinal channel 2102 and the first valve port 103 gradually closes. (See also...) Figure 4 When the valve stem 310 moves to the intermediate state, the longitudinal channel 2102 closes with the first valve hole 103, and the first valve port 102 closes with the second valve hole 104. The second gap G2 in the receiving cavity 2221, which was in the intermediate state, moves upward as the valve stem 310 moves downward (i.e., the third gap G3). When the second gap G2 disappears, the valve stem 310 begins to push the first valve needle 210 downward, and the first valve port 102 and the second valve hole 104 become connected. (See reference...) Figure 6 The valve stem 310 continues to move downward until it reaches the lower stop position. The longitudinal channel 2102 and the first valve hole 103 remain closed, and the conduction area between the first valve port 102 and the second valve hole 104 gradually increases.

[0100] like Figure 2 , Figure 4 and Figure 6As shown, based on the design of the valve port channel inside the first valve needle 210, in one embodiment of this disclosure, the valve port channel does not penetrate the body portion 211.

[0101] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the first valve needle 210 including the extension 212, in one embodiment of this disclosure, the outer wall surface of the extension 212 is provided with an annular groove, and the groove depth of the portions located at both ends along the axial direction of the groove is less than the groove depth of the middle portion of the groove.

[0102] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the first valve needle 210 including a body portion 211 and the body portion 211 being provided with a first sub-channel 2111, in one embodiment of this disclosure, the body portion 211 may be provided with at least two first sub-channels 2111, and the second sub-channel 2121 provided in the extension portion 212 is simultaneously connected to at least two first sub-channels 2111. Through the above design, this disclosure can improve the uniformity of fluid flow. In some embodiments, the body portion 211 may also be provided with only one first sub-channel 2111, and is not limited to this embodiment.

[0103] Based on the design of having at least two first sub-channels 2111 in the main body 211, in one embodiment of this disclosure, when the transverse channel 2101 passes through the main body 211, the same number of first sub-channels 2111 can be provided in two regions of the main body 211 located on both sides of the transverse channel 2101, and the first sub-channels 2111 provided in these two regions can be arranged symmetrically, with the axis of symmetry being, for example, the axis of the transverse channel 2101.

[0104] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the first valve needle 210 including an extension 212 and the extension 212 being provided with a second sub-channel 2121, in one embodiment of this disclosure, the end of the second sub-channel 2121 near the body portion 211 may be provided with an open structure 21211, the inner diameter of the open structure 21211 being larger than the inner diameter of the second sub-channel 2121, and the second sub-channel 2121 communicating with at least two first sub-channels 2111 simultaneously via the open structure 21211.

[0105] like Figure 2 , Figure 4 and Figure 6As shown, based on the design of the second sub-channel 2121, an open structure 21211 is provided. In one embodiment of this disclosure, the cross-section of the open structure 21211 can be an inverted trapezoid. In other embodiments of this disclosure, the cross-section of the open structure 21211 can also be other shapes, such as an arc shape, and is not limited to this embodiment.

[0106] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the first valve needle 210 including a body portion 211 and an extension portion 212, in one embodiment of this disclosure, the end face of the body portion 211 facing the extension portion 212 may have a first groove, and the end face of the extension portion 212 facing the body portion 211 is connected to the body portion 211. Furthermore, a first sub-channel 2111 opens into the bottom of the first groove, and a second sub-channel 2121 opens into the end face of the extension portion 212 facing the body portion 211. The distance between the bottom of the first groove and the end face of the body portion 211 is greater than or equal to zero.

[0107] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the first groove provided in the body portion 212, in one embodiment of this disclosure, the end face of the extension portion 212 facing the body portion 211 may be provided with a protrusion, which is accommodated in the first groove. The second sub-channel 2121 opens at the end face of the protrusion facing the body portion 211. Through the above design, this disclosure utilizes the cooperation between the protrusion and the first groove to increase the connection area between the body portion 211 and the extension portion 212. For example, when the body portion 211 and the extension portion 212 are connected by welding, this disclosure can increase the welding area, improve the connection strength between the body portion 211 and the extension portion 212, thereby improving the structural stability of the first valve needle 210.

[0108] like Figure 2 , Figure 4 and Figure 6 As shown, based on the design of the body portion 211 having a first groove and the extension portion 212 having a protrusion, in one embodiment of this disclosure, there may be a gap between the bottom of the first groove and the end face of the protrusion, such as the first gap G1 shown in the figure, through which the first sub-channel 2111 and the second sub-channel 2121 are connected.

[0109] See Figure 7 and Figure 8 , Figure 7 The image shows a representative axial sectional view of an electronic expansion valve that embodies the principles of this disclosure in another exemplary embodiment; Figure 8 China representatively shows Figure 7 An enlarged schematic diagram of part A in the diagram.

[0110] like Figure 7 and Figure 8 As shown, in one embodiment of this disclosure, taking the first valve needle 210 with a sealing structure (i.e., the first sealing structure 213 shown in the figure) as an example, the first valve needle 210 is provided with a flow regulating section, which is adjacent to the first sealing structure 213 on the side near the first valve port 102. The outer periphery of the flow regulating section is a flow regulating slope 2104, so that the outer diameter of the flow regulating section gradually decreases in the axial direction away from the sealing structure. Through the above design, this disclosure can utilize the flow regulating slope 2104 to achieve a broken-line flow curve when the first valve port 102 is open, thereby improving the flow performance of the first valve port 102. In addition, when the first valve needle 210 includes a body portion 211 and an extension portion 212, the flow regulating section is provided as a part of the extension portion 212.

[0111] like Figure 8 As shown, based on the design of the flow regulating section provided in the first valve needle 210, in one embodiment of this disclosure, the included angle α between the flow regulating slope 2104 and the axial direction can be 5°~60°, for example 5°, 10°, 15°, 20°, 30°, 45°, 60°, etc. Through the above design, this disclosure selects a suitable angle range for the flow regulating slope 2104, which can fully realize the broken-line flow curve while avoiding problems such as processing difficulties or affecting the flow performance of the first valve port 102 caused by the included angle α being too small or too large.

[0112] like Figure 2 , Figure 4 and Figure 6 As shown, in one embodiment of this disclosure, a first sealing ring 230 and a second sealing ring 240 may be provided between the first valve needle 210 and the valve seat assembly 100. The first sealing ring 230 is located on the side of the first valve hole 103 away from the second valve hole 104, and the second sealing ring 240 is located between the first valve hole 103 and the second valve hole 104. Through the above design, this disclosure can ensure that there is no electrical connection between the first valve hole 103 and the second valve hole 104.

[0113] like Figures 2 to 6As shown, in one embodiment of this disclosure, the electronic expansion valve may further include a first elastic element 410 located within the valve cavity 101. The first elastic element 410 provides a preload force when the first valve needle 210 closes the first valve port 102. One end of the first valve needle 210 is sealed to the first valve port 102, and the other end of the first valve needle 210 is provided with a first limiting plate 215 extending radially away from the first valve needle 210. The first elastic element 410 is located between the first limiting plate 215 and the inner wall of the valve cavity 101. Through the above design, this disclosure can further improve the sealing performance when the first valve port 102 is closed by utilizing the first elastic element 410, thus preventing leakage.

[0114] like Figure 2 As shown, in one embodiment of this disclosure, the valve seat assembly 100 includes a first valve seat 110 and a second valve seat 120, at least a portion of the second valve seat 120 extends into the first valve seat 110, a first valve needle 210 moves axially relative to the inner wall of the second valve seat 120, and a first elastic member 410 is located in the gap between the portion of the second valve seat 120 extending into the first valve seat 110 and the first valve seat 110.

[0115] like Figures 2 to 6As shown, in one embodiment of this disclosure, the electronic expansion valve may further include a second elastic element 420, which provides a pre-tightening force when the second valve needle 220 closes the second valve port 2103. For example, the second elastic element 420 may be located in the receiving cavity 2221 and connect the limiting portion 311 and the second valve needle 220. Accordingly, when the first valve needle 210 is pushed towards the first valve port 102 by the second valve needle 220, the first elastic element 410 is compressed, and the first elastic element 410 applies opposing elastic forces between the valve seat assembly 100 and the first valve needle 210. With the valve seat as a relatively fixed component, the elastic force applied by the first elastic element 410 to the first valve needle 210 is away from the first valve port 102 (i.e. towards the second valve needle 220), thereby achieving a pre-tightening sealing effect of the first valve needle 210 (e.g., the first sealing structure 213) on the first valve port 102. Furthermore, when the second valve port 2103 is opened, there is a gap between the end of the valve stem 310 facing the second valve needle 220 and the surface of the second valve needle 220 facing the valve stem 310, such as the second gap G2 shown in the attached figure. That is, the second gap G2 exists between the lower end of the valve stem 310 and the top surface of the second valve needle 220 (i.e., the bottom surface of the receiving cavity 2221). The valve stem 310 moves towards the first valve port 102, first moving a short distance until the valve stem 310 abuts against the top surface of the second valve needle 220. This short distance corresponds to the second gap G2. During the process of the valve stem 310 moving towards the first valve port 102 during this short distance, the second gap G2 is transferred to the space between the valve stem 310 and the top surface of the receiving cavity 2221, thus forming the third gap G3. Accordingly, since the second gap G2 disappears, the second elastic element 420 is compressed, and the second elastic element 420 applies opposite elastic forces between the valve stem 310 and the second valve needle 220. Taking the valve stem 310 as a relatively fixed component, the elastic force applied by the second elastic element 420 to the second valve needle 220 is towards the second valve port 2103 (i.e. towards the first valve port 102 and the first valve needle 210), thereby achieving the pre-tight sealing effect of the second valve needle 220 (e.g., the second sealing structure 221) on the second valve port 2103.

[0116] like Figure 3 and Figure 5As shown, based on the design of the elastic preload assembly including the second elastic element 420, in one embodiment of this disclosure, a pressure sleeve 222 can be connected to the end of the second valve needle 220 facing the valve stem 310. The pressure sleeve 222 and the second valve needle 220 together form a receiving cavity 2221. The end of the valve stem 310 facing the second valve needle 220 extends into the receiving cavity 2221. A limiting portion 311 is provided on the portion of the valve stem 310 extending into the receiving cavity 2221. The limiting portion 311 cooperates with the pressure sleeve 222 to limit and prevent the end of the valve stem 310 from dislodging from the receiving cavity 2221. Accordingly, when the valve stem 310 moves away from the first valve port 102 (i.e., away from the second valve needle 220), the limiting part 311 abuts against the top surface of the receiving cavity 2221, pulling the pressure sleeve 222 and the second valve needle 220 upward together (i.e., away from the first valve port 102 and the first valve needle 210), thereby opening the second valve port 2103. Based on this, the second elastic element 420 can connect the limiting part 311 and the second valve needle 220. To form the aforementioned second gap G2 and third gap G3, the axial distance d1 between the end face of the limiting part 311 facing away from the second valve needle 220 and the end face of the valve stem 310 facing the second valve needle 220 is less than the axial length d2 of the receiving cavity 2221.

[0117] like Figure 3 As shown, in one embodiment of this disclosure, a T-shaped bushing 312 is further provided in the receiving cavity 2221. The top surface of the bushing 312 is fitted with the limiting part 311. The second elastic member 420 is sleeved on the bushing 312 and located between the bushing 312 and the second valve needle 220. The maximum distance h between the bottom surface of the bushing 312 and the second valve needle 220 is the maximum distance that the valve stem 310 can move relative to the second valve needle 220.

[0118] Based on the design of the valve stem 310 with a limiting part 311, in one embodiment of this disclosure, the drive assembly 300 can drive the valve stem 310 via a threaded drive method, that is, the valve stem 310 can be a screw, and the valve stem 310 will rotate when driven by the drive assembly 300 to move axially. Furthermore, the limiting part 311 can be a bearing, and the pressure sleeve 222 can also be understood as a bearing sleeve used to arrange the bearing and enable it to move axially, and the receiving cavity 2221 can also be understood as a bearing cavity. In other embodiments of this disclosure, the valve stem 310 may also adopt other driving forms, and is not limited to the above embodiments.

[0119] See Figure 9 and Figure 10 , Figure 9 The image shows a representative axial sectional view of an electronic expansion valve that embodies the principles of this disclosure in yet another exemplary embodiment; Figure 10 China representatively shows Figure 9 An enlarged schematic diagram of part B in the diagram.

[0120] like Figure 9 and Figure 10 As shown, based on the design of the electronic expansion valve including a first elastic element 410 and a second elastic element 420, in one embodiment of this disclosure, the electronic expansion valve may further include a third elastic element 430, which is located within the valve cavity 101. A second limiting plate 216 is also provided at the other end of the first valve needle 210, extending radially close to the first valve needle 210. The third elastic element 430 is located between the second limiting plate 216 and the second valve needle 220. Accordingly, the elastic preload force when the first valve needle 210 closes the first valve port 102 is the sum of the preload forces of the first elastic element 410 and the second elastic element 420, and the elastic preload force when the second valve needle 220 closes the second valve port 2103 is the difference between the preload forces of the third elastic element 430 and the second elastic element 420. Through the above design, by utilizing the added third elastic element 430, this disclosure can further ensure that the pre-tightening force of the first valve port 102 is increased while the pre-tightening force of the second valve port 2103 remains unchanged, thereby further improving the sealing performance of the first valve port 102 in the intermediate state.

[0121] See Figure 11 and Figure 12 , Figure 11 The image shows a representative axial sectional view of an electronic expansion valve that embodies the principles of this disclosure in yet another exemplary embodiment; Figure 12 China representatively shows Figure 11 An enlarged schematic diagram of part C in the diagram.

[0122] like Figure 11 and Figure 12 As shown, based on the design of the elastic pretensioning assembly including a first elastic pretensioning structure and a second elastic pretensioning structure, in one embodiment of this disclosure, the first elastic pretensioning structure may include a first elastic element 410, and the connection position of the first elastic element 410 can be referred to... Figure 2 or Figure 9 In the illustrated embodiment, for example, a first elastic member 410 connects the first valve needle 210 and the valve seat assembly 100. Furthermore, the second elastic preload structure may include a third elastic member 430, which connects the first valve needle 210 and the second valve needle 220. In other words, compared to... Figure 2 In the illustrated embodiment, the second elastic preload structure replaces the second elastic member 420 connecting the valve stem 310 and the second valve needle 220 with a third elastic member 430 connecting the second valve needle 220 and the first valve needle 210. Furthermore, compared to... Figure 9In the illustrated embodiment, the second elastic preload structure eliminates the second elastic element 420, utilizing only the third elastic element 430 as the second elastic preload structure to provide elastic preload force to the second valve port 2103. Through this design, the present disclosure further reduces the number of components and simplifies structural complexity.

[0123] In one embodiment of this disclosure, the drive assembly 300 includes a valve stem 310, which is axially movable and used to push and pull the second valve needle 220 axially. The second valve needle 220 has a receiving cavity 2221 inside. The end of the valve stem 310 extending into the receiving cavity 2221 toward the second valve needle 220 is provided with a limiting part 311, which is limited and engaged with a pressure plate at the opening of the receiving cavity 2221. The second valve needle 220 is provided with a second sealing structure 221 that seals with the second valve port.

[0124] See Figures 13 to 15 , Figure 13 The image shows a representative axial sectional view of an electronic expansion valve that embodies the principles of this disclosure in another exemplary embodiment. Figure 14 China representatively shows Figure 13 An enlarged schematic diagram of part E in the diagram; Figure 15 A schematic diagram of the structure of baffle 214 is shown in the figure.

[0125] like Figures 13 to 15 As shown, in one embodiment of this disclosure, when the electronic expansion valve is provided with an elastic pre-tightening component and the second elastic pre-tightening structure includes a third elastic element 430, regardless of whether the second elastic pre-tightening structure also includes a second elastic element 420, the end face of the first valve needle 210 facing the second valve needle 220 can be provided with a second groove 2113, and the second valve needle 220 is partially accommodated in the second groove 2113. The longitudinal channel 2102 of the first valve needle 210 can open into the bottom of the groove of the second groove 2113, that is, after the longitudinal channel 2102 communicates with the second groove 2113, it still axially penetrates the first valve needle 210. Based on this, a baffle 214 is provided at the opening of the second groove 2113 of the first valve needle 210. The baffle 214 includes an integrally formed first stop portion 2141 and a second stop portion 2142. The first stop portion 2141 extends radially away from the first valve needle 210, and the second stop portion 2142 extends radially to the opening of the second groove 2113. Based on this, the first elastic element 410 connects the first stop portion 2141 and the valve seat assembly 100, and the third elastic element 430 connects the second stop portion 2142 and the portion of the second valve needle 220 accommodated in the second groove 2113. Through the above design, this disclosure can simultaneously achieve the arrangement of the first elastic element 410 and the third elastic element 430 using a single baffle 214, which helps reduce the number of components and lower structural complexity. In other embodiments of this disclosure, for example... Figure 10 or Figure 12 In the illustrated embodiment, to achieve the arrangement of the first elastic member 410 and the third elastic member 430, when the first valve needle 210 is provided with the second groove 2113, two relatively independent baffles can also be provided on the inner and outer sides of the groove opening of the second groove 2113, and it is not limited to this embodiment.

[0126] Based on the design of the first valve needle 210 being connected to the baffle 214, in one embodiment of this disclosure, the baffle 214 and the first valve needle 210 are connected via a through-welding process.

[0127] like Figure 15 As shown, based on the design of connecting the baffle 214 and the first valve needle 210 via a through-welding process, in one embodiment of this disclosure, a stepped structure 2143 can be provided on the surface of the baffle 214 facing away from the first valve needle 210. This allows the surface of the baffle 214 to form a first stepped surface 21431 radially located on the outer ring and a second stepped surface 21432 radially located on the inner ring. The first stepped surface 21431 is axially further away from the first valve needle 210 than the second stepped surface 21432, and the second stepped surface 21432 is directly opposite the outer edge of the groove opening of the second groove 2113. Through the above design, this disclosure, by machining the stepped structure 2143 on the surface of the baffle 214, makes it easier to accurately locate the welding position (i.e., the corresponding position between the baffle 214 and the groove opening of the second groove 2113) in the through-welding process, reducing the processing difficulty and improving efficiency and yield.

[0128] It should be noted that the electronic expansion valves shown in the accompanying drawings and described in this specification are merely a few examples among many electronic expansion valves capable of employing the principles of this disclosure. It should be clearly understood that the principles of this disclosure are by no means limited to any detail or component of the electronic expansion valves shown in the accompanying drawings or described in this specification.

[0129] In summary, the electronic expansion valve disclosed herein includes a valve seat assembly 100, a valve core assembly 200, and a drive assembly 300. The valve seat assembly 100 has a first valve port 102, a first valve hole 103, and a second valve hole 104 closer to the first valve port 102. The valve core assembly 200 includes first and second valve needles 220. The first valve needle 210 is sealed to the first valve port 102 and has an internal fluid passage. The fluid passage has the second valve port 102, with one end communicating with the first valve hole 103 and the other end communicating with the first valve port 102. A transverse channel 2101 opens onto the side of the first valve needle 210. A longitudinal channel 2102 extends axially. The second valve port 2103 connects the other end of the first valve needle 210 to the transverse channel 2101. The second valve needle 220 is sealed to the second valve port 2103. The drive assembly 300 drives the first valve needle 210 and the second valve needle 220 to move axially, thereby controlling the first and second valve ports 2103. When the first valve port 102 is closed and the second valve port 2103 is open, the first valve port 102 is disconnected from the second valve port 2103, and the first valve orifice 103 is connected to the first valve port 102 via a fluid passage. When the first valve port 102 is open and the second valve port 2103 is closed, the second valve orifice 104 is connected to the first valve port 102, and the first valve port 102 is disconnected from the first valve orifice 103. When the first valve port 102 is closed and the second valve port 2103 is closed, the second valve orifice 104 is disconnected from the first valve port 102, and the first valve port 102 is disconnected from the first valve orifice 103. Through the above design, this disclosure enables the simultaneous closure of the first valve port 102 and the second valve port 2103. Furthermore, it enables the connection between the first valve port 102 and the second valve hole 104, as well as the connection between the longitudinal channel 2102 and the first valve hole 103. Based on this, the electronic expansion valve proposed in this disclosure avoids the need for complex channels on the valve seat assembly 100 to connect the second valve port 2103, thus simplifying the product structure and reducing manufacturing difficulty and cost.

[0130] The exemplary embodiments of the electronic expansion valve proposed in this disclosure have been described and / or illustrated in detail above. However, the embodiments of this disclosure are not limited to the specific embodiments described herein; rather, components and / or steps of each embodiment may be used independently and separately from other components and / or steps described herein. Each component and / or step of one embodiment may also be used in combination with other components and / or steps of other embodiments. In describing the elements / components / etc. described and / or illustrated herein, the terms “a,” “an,” and “the above” are used to indicate the presence of one or more elements / components / etc. The terms “comprising,” “including,” and “having” are used to indicate an open-ended inclusion and to mean that additional elements / components / etc. may exist in addition to those listed. Furthermore, the terms “first” and “second” in the claims and description are used only as illustrative marks and are not intended to limit the numerical scope of the object.

[0131] Although the electronic expansion valve proposed in this disclosure has been described according to different specific embodiments, those skilled in the art will recognize that modifications may be made to the implementation of this disclosure within the spirit and scope of the claims.

Claims

1. An electronic expansion valve, characterized in that, include: A valve seat assembly (100) has a valve chamber (101) inside. The valve seat assembly (100) is provided with a first valve port (102), a first valve hole (103) and a second valve hole (104) that is closer to the first valve port (102) than the first valve hole (103). Valve core assembly (200), including: A first valve needle (210) is disposed in the valve cavity (101); one end of the first valve needle (210) is sealed to the first valve port (102); a fluid passage is provided inside the first valve needle (210); the fluid passage is provided with a second valve port (2103), one end of the fluid passage is connected to the first valve hole (103), and the other end is connected to the first valve port (102); and A second valve needle (220) is disposed in the valve cavity (101); the end of the second valve needle (220) facing the first valve port (102) is in sealing engagement with the second valve port (2103); and A drive assembly (300) is used to drive the first valve needle (210) and the second valve needle (220) to move axially, so as to realize the opening and closing control of the first valve port (102) and the second valve port (2103); When the first valve port (102) is closed and the second valve port (2103) is open, the first valve port (102) is isolated from the second valve hole (104), and the first valve hole (103) is connected to the first valve port (102) via the fluid passage; when the first valve port (102) is open and the second valve port (2103) is closed, the second valve hole (104) is connected to the first valve port (102), and the first valve port (102) is disconnected from the first valve hole (103); when the first valve port (102) is closed and the second valve port (2103) is closed, the second valve hole (104) is disconnected from the first valve port (102), and the first valve port (102) is disconnected from the first valve hole (103).

2. The electronic expansion valve according to claim 1, characterized in that, The fluid passage includes a transverse channel (2101), a longitudinal channel (2102), and a valve port channel disposed inside the first valve needle (210); the second valve port (2103) is located in the valve port channel; at least one end of the transverse channel (2101) opens to the side of the first valve needle (210); the longitudinal channel (2102) passes through the first valve needle (210) axially; the valve port channel connects the end of the first valve needle (210) facing away from the first valve port (102) with the transverse channel (2101); the end of the first valve needle (210) facing away from the first valve port (102) is connected to the first valve port (102) through the longitudinal channel (2102); the first valve needle (210) includes: The main body (211) is disposed in the valve cavity (101), and is provided with the transverse channel (2101) and the valve port channel; and The extension (212) is connected to the main body (211) at one end and a sealing structure is provided at the other end. When the first valve port (102) is closed, the sealing structure seals the first valve port (102). The main body (211) is provided with a first sub-channel (2111) that extends through the axis, and the extension (212) is provided with a second sub-channel (2121) that extends through the axis. The first sub-channel (2111) and the second sub-channel (2121) are connected to form the longitudinal channel (2102).

3. The electronic expansion valve according to claim 2, characterized in that, The valve port channel does not penetrate the main body (211).

4. The electronic expansion valve according to claim 2, characterized in that, The outer wall of the extension (212) is provided with an annular groove, and the groove depth at both ends along the axial direction is less than the groove depth in the middle of the groove.

5. The electronic expansion valve according to claim 2, characterized in that, The main body (211) is provided with at least two first sub-channels (2111); the second sub-channel (2121) is provided with an open structure (21211) near the end of the main body (211), the inner diameter of the open structure (21211) is larger than the inner diameter of the second sub-channel (2121), and the second sub-channel (2121) is connected to at least two first sub-channels (2111) simultaneously through the open structure (21211).

6. The electronic expansion valve according to claim 2, characterized in that, The end face of the main body (211) facing the extension (212) is provided with a first groove, and the end face of the extension (212) facing the main body (211) is connected to the main body (211); the first sub-channel (2111) opens at the bottom of the first groove, and the second sub-channel (2121) opens at the end face of the extension (212) facing the main body (211); the distance between the bottom of the first groove and the end face of the main body (211) is greater than or equal to zero.

7. The electronic expansion valve according to claim 6, characterized in that, The extension (212) has a protrusion on the end face of the body (211) and the protrusion is accommodated in the first groove; the second sub-channel (2121) opens on the end face of the protrusion facing the body (211).

8. The electronic expansion valve according to claim 1, characterized in that, The first valve needle (210) extends from the end opposite to the second valve needle (220) out of the first valve port (102) and is provided with a sealing structure. When the first valve port (102) is closed, the sealing structure seals the side of the first valve port (102) opposite to the second valve port (2103). The first valve needle (210) is provided with a flow regulating section, which is adjacent to the sealing structure on the side near the first valve port (102). The outer periphery of the flow regulating section is a flow regulating inclined surface (2104) so ​​that the outer diameter of the flow regulating section gradually decreases in the axial direction away from the sealing structure.

9. The electronic expansion valve according to claim 1, characterized in that, A first sealing ring (230) and a second sealing ring (240) are provided between the first valve needle (210) and the valve seat assembly (100); the first sealing ring (230) is located on the side of the first valve hole (103) away from the second valve hole (104), and the second sealing ring (240) is located between the first valve hole (103) and the second valve hole (104).

10. The electronic expansion valve according to claim 1, characterized in that, The electronic expansion valve also includes: A first elastic element (410) is located inside the valve cavity (101). The first elastic element (410) is used to provide a preload force when the first valve needle (210) closes the first valve port (102). One end of the first valve needle (210) is sealed to the first valve port (102). The other end of the first valve needle (210) is provided with a first limiting plate (215). The first limiting plate (215) extends radially away from the first valve needle (210). The first elastic element (410) is located between the first limiting plate (215) and the inner wall of the valve cavity (101).

11. The electronic expansion valve according to claim 10, characterized in that, The valve seat assembly (100) includes a first valve seat (110) and a second valve seat (120), at least a portion of the second valve seat (120) extends into the first valve seat (110), the first valve needle (210) moves axially relative to the inner wall of the second valve seat (120), and the first elastic member (410) is located in the gap between the portion of the second valve seat (120) extending into the first valve seat (110) and the first valve seat (110).

12. The electronic expansion valve according to claim 1, characterized in that, The electronic expansion valve also includes: The second elastic element (420) is used to provide a preload force when the second valve needle (220) closes the second valve port (2103); the drive assembly (300) includes a valve stem (310) which is axially movable and used to push and pull the second valve needle (220) axially; a pressure sleeve (222) is connected to the end of the second valve needle (220) facing the valve stem (310), and the pressure sleeve (222) and the second valve needle (220) together form a receiving cavity (2221); the end of the valve stem (310) facing the second valve needle (220) extends into the receiving cavity (2221) and is provided with a limiting part (311), and the limiting part (311) is limitedly engaged with the pressure sleeve (222); the second elastic element (420) is located in the receiving cavity (2221) and connects the limiting part (311) and the second valve needle (220).

13. The electronic expansion valve according to claim 12, characterized in that, The cavity (2221) is also provided with a T-shaped bushing (312), the top surface of the bushing (312) is in contact with the limiting part (311), the second elastic member (420) is sleeved on the bushing (312) and located between the bushing (312) and the second valve needle (220), and the maximum distance (h) between the bottom surface of the bushing (312) and the second valve needle (220) is the maximum distance that the valve stem (310) can move relative to the second valve needle (220).

14. The electronic expansion valve according to claim 12, characterized in that, The electronic expansion valve also includes a third elastic element (430) located in the valve cavity (101), and a second limiting plate (216) is provided at the other end of the first valve needle (210). The second limiting plate (216) extends radially close to the first valve needle (210), and the third elastic element (430) is located between the second limiting plate (216) and the second valve needle (220).

15. The electronic expansion valve according to claim 1, characterized in that, The drive assembly (300) includes a valve stem (310) that is axially movable and is used to push and pull the second valve needle (220) axially. The second valve needle (220) has a receiving cavity (2221) inside. The end of the valve stem (310) extending toward the second valve needle (220) extends into the receiving cavity (2221) and is provided with a limiting part (311). The limiting part (311) is limited and cooperates with the pressure plate at the opening of the receiving cavity (2221). The second valve needle (220) is provided with a second sealing structure (221) that seals with the second valve port.

16. The electronic expansion valve according to claim 14 or 15, characterized in that, The first valve needle (210) has a second groove (2113) on its end face facing the second valve needle (220), and the second valve needle (220) is partially accommodated in the second groove (2113); the fluid passage includes a longitudinal channel (2102) disposed inside the first valve needle (210), the longitudinal channel (2102) passes through the first valve needle (210) axially, and the longitudinal channel (2102) opens at the bottom of the groove of the second groove (2113); wherein, a baffle (214) is disposed at the opening of the second groove (2113) of the first valve needle (210), the baffle (214) includes an integrally disposed first stop portion (2141) and a second stop portion (2142), the first stop portion (2141) extends radially away from the first valve needle (210), and the second stop portion (2142) extends radially to the opening of the groove (2113).

17. The electronic expansion valve according to claim 16, characterized in that, The baffle (214) is connected to the first valve needle (210) via a through-welding process.

18. The electronic expansion valve according to claim 17, characterized in that, The baffle (214) has a stepped structure (2143) on its surface facing away from the first valve needle (210), so that the surface of the baffle (214) has a first stepped surface (21431) located on the outer ring in the radial direction and a second stepped surface (21432) located on the inner ring. The first stepped surface (21431) is axially further away from the first valve needle (210) than the second stepped surface (21432), and the second stepped surface (21432) is directly opposite the outer edge of the groove of the second groove (2113).

Images