Electronic expansion valve

Abstract

A valve element assembly of the electronic expansion valve comprises a first valve needle and a second valve needle. The first valve needle is arranged in a valve cavity of the valve seat assembly, and one end of the first valve needle is in sealing fit with a first valve port of the valve cavity. The first valve needle is provided with a circulation cavity and a transverse channel extending in the radial direction, and the transverse channel communicates with the valve cavity. One end of the second valve port is communicated with the transverse channel, and the other end of the second valve port is communicated with the circulation cavity; the first valve needle is provided with a guide part which is positioned at the opening of the circulation cavity and is provided with a guide surface; the second valve needle is partially inserted into the circulation cavity, and one end, facing the first valve port, of the second valve needle is in sealing fit with the second valve port; the guide surface is matched with the shape of at least part of the periphery of the second valve needle so as to guide the second valve needle; a driving assembly of the electronic expansion valve comprises a screw rod, the screw rod is connected to the second valve needle, and the screw rod can drive the second valve needle to move in the axial direction relative to the first valve needle so as to control opening and closing of the first valve port and the second valve port.

Description

Technical Field

[0001] The present disclosure relates to the technical field of valves, and more particularly to an electronic expansion valve. Background Art

[0002] As a throttling element, an electronic expansion valve is used to regulate the on-off and flow rate of a fluid. In the existing design of an electronic expansion valve, the valve core assembly of the electronic expansion valve is arranged in the valve cavity of the valve seat and includes a large valve needle and a small valve needle. The large valve needle is used to cooperate with the large valve port of the valve cavity to realize the opening and closing of the large valve port. The large valve needle is provided with a small valve port, and the small valve needle is partially inserted into the large valve needle and used to cooperate with the small valve port to realize the opening and closing of the small valve port. In the above existing solution, the small valve needle can tilt relative to the axial direction during movement, affecting stability and reliability. Summary of the Utility Model

[0003] A main object of the present disclosure is to overcome at least one defect of the above existing technology, and to provide an electronic expansion valve with a valve core assembly having better stability and reliability.

[0004] To achieve the above object, the present disclosure adopts the following technical solutions:

[0005] According to one aspect of the present disclosure, there is provided an electronic expansion valve, which includes a valve seat assembly, a valve core assembly, and a driving assembly; a valve cavity is provided inside the valve seat assembly, and a first valve port is provided in the valve cavity; the valve core assembly includes a first valve needle and a second valve needle; the first valve needle is arranged in the valve cavity, and one end of the first valve needle is in sealing cooperation with the first valve port; the first valve needle is provided with a flow cavity and a transverse channel extending radially, and the transverse channel communicates with the valve cavity; a second valve port is provided in the flow cavity, one end of the second valve port communicates with the transverse channel, and the other end communicates with the flow cavity; the first valve needle is provided with a guiding portion, the guiding portion is located at the opening of the flow cavity and has a guiding surface; the second valve needle is partially inserted into the flow cavity, and one end of the second valve needle facing the first valve port is in sealing cooperation with the second valve port; the guiding surface matches the shape of at least part of the outer circumference of the second valve needle to guide the second valve needle; the driving assembly includes a screw rod, the screw rod is connected to the second valve needle, and the screw rod can drive the second valve needle to move axially relative to the first valve needle to realize the opening and closing control of the first valve port and the second valve port.

[0006] According to one embodiment of the present disclosure, a valve core sealing ring is provided between the first valve needle and the valve seat assembly, and a part of the valve cavity on the side of the valve core sealing ring away from the first valve port is a back pressure cavity; the first valve needle is provided with a balance channel, and two ends of the balance channel are respectively communicated with the first valve port and the back pressure cavity; the gaps between the guiding surface and the second valve needle are respectively communicated with the back pressure cavity and the circulation cavity.

[0007] According to one embodiment of the present disclosure, the balance channel includes a circulation channel and a longitudinal channel provided on the first valve needle, the circulation cavity is located between the circulation channel and the longitudinal channel, and the circulation channel communicates the circulation cavity with the back pressure cavity; the longitudinal channel communicates the first valve port with the circulation cavity.

[0008] According to one embodiment of the present disclosure, in the circumferential direction, a part of the opening of the second valve needle and the circulation cavity that is not occupied by the guiding part forms the circulation channel.

[0009] According to one embodiment of the present disclosure, the valve core assembly includes at least two of the guiding parts, and the at least two guiding parts are arranged at intervals in the circumferential direction and form at least two of the circulation channels arranged at intervals in the circumferential direction.

[0010] According to one embodiment of the present disclosure, the at least two guiding parts are evenly distributed in the circumferential direction.

[0011] According to one embodiment of the present disclosure, the guiding part has an annular structure, a guiding hole is formed in the middle of the guiding part, the hole wall of the guiding hole is the guiding surface, and the second valve needle passes through the guiding hole; wherein, the circulation channel is arranged on the guiding part, and the circulation channel axially penetrates the guiding part.

[0012] According to one embodiment of the present disclosure, the circulation channel is a through hole, and the through hole is arranged at intervals with the guiding hole.

[0013] According to one embodiment of the present disclosure, the circulation channel is a through groove, and the notch of the through groove is communicated with the guiding hole.

[0014] According to one embodiment of the present disclosure, the guiding part is provided with at least two of the circulation channels.

[0015] According to one embodiment of the present disclosure, the at least two circulation channels are evenly distributed in the circumferential direction.

[0016] According to one embodiment of the present disclosure, in the radial direction, the gap between the guiding surface of the guiding part and the outer periphery of the second valve needle is less than or equal to 0.1 mm.

[0017] As can be seen from the above technical solutions, the advantages and positive effects of the electronic expansion valve proposed by the present disclosure are as follows:

[0018] The electronic expansion valve proposed by the present disclosure includes a valve seat assembly, a valve core assembly, and a driving assembly; a first valve port is provided in the valve cavity of the valve seat assembly; the valve core assembly includes a first valve needle and a second valve needle; one end of the first valve needle is in sealing fit with the first valve port; a flow cavity and a transverse channel extending radially are provided on the first valve needle, and the transverse channel communicates with the valve cavity; a second valve port is provided in the flow cavity, one end of the second valve port communicates with the transverse channel, and the other end communicates with the flow cavity; a part of the second valve needle is inserted into the flow cavity, and one end of the second valve needle facing the first valve port is in sealing fit with the second valve port; the guiding surface matches the shape of at least part of the outer circumference of the second valve needle to guide the second valve needle; the driving assembly includes a screw rod, the screw rod is connected to the second valve needle, and the screw rod can drive the second valve needle to move axially relative to the first valve needle. Through the above structural design, the present disclosure utilizes the guiding part to realize the guiding function of the second valve needle, avoids a large-angle inclination of the second valve needle during the movement process, ensures the stability and reliability of the movement of the valve core assembly, and avoids leakage at the second valve port due to the inclination of the second valve needle in the closed state. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] By considering the following detailed description of the preferred embodiments of the present disclosure in conjunction with the drawings, various objectives, features, and advantages of the present disclosure will become more apparent. The drawings are only exemplary illustrations of the present disclosure and are not necessarily drawn to scale. In the drawings, the same reference numerals always represent the same or similar components. Among them:

[0020] Figure 1 is a perspective structural view of an electronic expansion valve shown according to an exemplary embodiment;

[0021] Figure 2 is Figure 1 a bottom view of;

[0022] Figure 3 and Figure 4 are respectively sectional schematic views taken along the straight lines P-P and Q-Q in Figure 2 ;

[0023] Figure 5 is Figure 3 an enlarged schematic view of a partial structure shown;

[0024] Figure 6 is Figure 1 a perspective structural view of the valve core assembly of the electronic expansion valve shown;

[0025] Figure 7 is Figure 6 a perspective structural view of the first assembly shown;

[0026] Figure 8 is Figure 7 the top view;

[0027] Figure 9 is the solid cross-sectional view taken along the line F-F in Figure 8 ;

[0028] Figure 10 is the top view of the first valve needle of an electronic expansion valve shown according to another exemplary embodiment;

[0029] Figure 11 is the top view of the first valve needle of an electronic expansion valve shown according to another exemplary embodiment.

[0030] The reference numerals are explained as follows:

[0031] 100. Valve seat assembly;

[0032] 101. Valve cavity;

[0033] 1011. First valve port;

[0034] 1014. Back pressure cavity;

[0035] 200. Spool assembly;

[0036] 210. First valve needle;

[0037] 2101. Flow cavity;

[0038] 2102. Second valve port;

[0039] 2103. Lateral channel;

[0040] 2104. Longitudinal channel;

[0041] 2105. Flow channel;

[0042] 211. First assembly;

[0043] 212. Second assembly;

[0044] 213. Spool seal ring;

[0045] 220. Second valve needle;

[0046] 221. Transmission part;

[0047] 270. Guide part;

[0048] 2701. Guide surface;

[0049] 2702. Guide hole;

[0050] 400. Driving component;

[0051] 430. Screw;

[0052] 500. Housing. Detailed implementation

[0053] Typical embodiments embodying the features and advantages of the present disclosure will be described in detail in the following description. It should be understood that the present disclosure can have various variations in different embodiments, all of which do not depart from the scope of the present disclosure, and the descriptions and drawings therein are for illustrative purposes in essence and not for limiting the present disclosure.

[0054] In the following description of different exemplary embodiments of the present disclosure, reference is made to the accompanying drawings, which form a part of the present disclosure, and in which different exemplary structures, systems, and steps that can implement various aspects of the present disclosure are shown by way of example. It should be understood that other specific solutions of components, structures, exemplary devices, systems, and steps can be used, and structural and functional modifications can be made without departing from the scope of the present disclosure. Moreover, although terms such as "above", "between", "inside", etc. may be used in this specification to describe different exemplary features and elements of the present disclosure, these terms are used herein only for convenience, for example, according to the directions of the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional direction of the structure to fall within the scope of the present disclosure.

[0055] Refer to Figure 1 , which representatively shows a three-dimensional structural schematic diagram of the electronic expansion valve proposed by the present disclosure. In this exemplary embodiment, the electronic expansion valve proposed by the present disclosure is described by taking the valve applied to the refrigeration system as an example. It is easily understood by those skilled in the art that, in order to apply the relevant designs of the present disclosure to other application scenarios, various modifications, additions, substitutions, deletions, or other changes are made to the following specific implementation manners, and these changes are still within the scope of the principle of the electronic expansion valve proposed by the present disclosure.

[0056] As Figure 1 shown, in an embodiment of the present disclosure, the electronic expansion valve proposed by the present disclosure includes a valve seat assembly 100, a valve core assembly 200, and a driving component 400. With reference to Figures 2 to 9 , Figure 2 representatively shows the Figure 1 bottom view; Figure 3 and Figure 4 respectively representatively show the cross-sectional schematic diagrams taken along the Figure 2 straight line P-P and straight line Q-Q in Figure 5 representatively shows the Figure 3An enlarged schematic view of the partial structure shown, in which the axially-sectional structure of the valve core assembly 200 is specifically shown; Figure 6 A schematic perspective view of the valve core assembly 200 is representatively shown therein; Figure 7 A schematic perspective view of the first assembly 211 is representatively shown therein; Figure 8 Representatively shown therein is Figure 7 the top view; Figure 9 Representatively shown therein is along Figure 8 the solid cross-sectional view taken along the straight line F-F in . The structures, connection methods, and functional relationships of the main components of the electronic expansion valve proposed in the present disclosure will be described in detail below with reference to the above-mentioned drawings.

[0057] As Figures 1 to 7 shown, in an embodiment of the present disclosure, a valve cavity 101 is provided inside the valve seat assembly 100, and a first valve port 1011 is provided in the valve cavity 101. 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, and one end of the first valve needle 210 is in sealing cooperation with the first valve port 1011; a flow cavity 2101 and a transverse channel 2103 extending radially are provided on the first valve needle 210, and the transverse channel 2103 communicates with the valve cavity 101. A second valve port 2102 is provided in the flow cavity 2101, one end of the second valve port 2102 communicates with the transverse channel 2103, and the other end of the second valve port 2102 communicates with the flow cavity 2101. A guiding portion 270 is provided on the first valve needle 210, and the guiding portion 270 is located at the opening of the flow cavity 2101 and has a guiding surface 2701. The second valve needle 220 is partially inserted into the flow cavity 2101, and one end of the second valve needle 220 facing the first valve port 1011 is in sealing cooperation with the second valve port 2102. The guiding surface 2701 of the guiding portion 270 matches the shape of at least a part of the outer periphery of the second valve needle 220, thereby realizing the guiding of the second valve needle 220. The driving assembly 400 includes a screw 430, the screw 430 is connected to the second valve needle 220, and the screw 430 can drive the second valve needle 220 to move axially relative to the first valve needle 210 to realize the opening and closing control of the first valve port 1011 and the second valve port 2102. For example, the driving assembly 400 can be disposed in a housing 500 and is located at one end of the valve seat assembly 100 away from the first valve port 1011. The screw 430 is in guiding cooperation with other structures of the electronic expansion valve, and the second valve needle 220 is located at the end of the screw 430 and is far from the guiding structure of the screw 430. Therefore, the second valve needle 220 is prone to tilt during movement. Through the above structural design, the present disclosure utilizes the guiding portion 270 to realize the guiding function of the second valve needle 220, avoid a large-angle tilt of the second valve needle 220 during movement, ensure the stability and reliability of the movement of the valve core assembly 200, and avoid leakage of the second valve port 2102 due to the tilt of the second valve needle 220 in the closed state.

[0058] As Figures 3 to 6 shown, in an embodiment of the present disclosure, a valve core seal ring 213 is provided between the first valve needle 210 and the valve seat assembly 100. The part of the valve cavity 101 on the side away from the first valve port 1011 of the valve core seal ring 213 is the back pressure cavity 1014. The first valve needle 210 is provided with a balance channel, and both ends of the balance channel are respectively communicated with the first valve port 1011 and the back pressure cavity 1014. Accordingly, an internal balance structure is realized for the first valve needle 210, and the fluid force acting on the first valve needle 210 can be reduced. Moreover, the gaps between the guide surface 2701 of the guide part 270 and the second valve needle 220 are respectively communicated with the back pressure cavity 1014 and the flow cavity 2101, that is, there is no sealing structure between the second valve needle 220 and the first valve needle 210, and a non-internal balance structure is realized for the second valve needle 220, and the second valve needle 220 will be subjected to fluid force. Through the above structural design, since the first valve needle 210 adopts the above non-internal balance structure in the present disclosure, it is possible to avoid arranging an additional sealing ring between the first valve needle 210 and the second valve needle 220, the number of parts of the electronic expansion valve can be reduced, and the structural complexity can be reduced. Since the arrangement of the above sealing ring is avoided, the present disclosure also does not need to weld the pressing piece for installing the sealing ring, the welding process can be reduced, and it is beneficial to improve the production efficiency of the product. On this basis, compared with the existing solution, when the additional sealing ring arranged between the first valve needle 210 and the second valve needle 220 is cancelled, the second valve needle 220 is more likely to tilt at a large angle during movement. In this regard, through the guiding function of the guide part 270 in the present disclosure, the guiding requirement for the second valve needle 220 in this case can be further met, which is beneficial to the specific implementation of the design of cancelling the additional sealing ring.

[0059] As Figures 3 to 7 shown, in an embodiment of the present disclosure, in order to make the pressures at the upper and lower ends of the first valve needle 210 equal, the balance channel includes a flow channel 2105 and a longitudinal channel 2104 provided on the first valve needle 210. The flow cavity 2101 is located between the flow channel 2105 and the longitudinal channel 2104. The flow channel 2105 communicates the flow cavity 2101 with the back pressure cavity 1014; the longitudinal channel 2104 communicates the first valve port 1011 with the flow cavity 2101.

[0060] In an embodiment of the present disclosure, along the radial direction, the gap between the guide surface 2701 of the guide part 270 and the outer periphery of the second valve needle 220 may be less than or equal to 0.1 mm. Through the above structural design, the present disclosure can avoid the above gap being too small. When the gap is too small, it is easy to cause friction between the guide surface 2701 and the second valve needle 220, affecting the movement of the second valve needle 220. At the same time, the present disclosure can avoid the above gap being too large, thereby ensuring that the first valve needle 210 tilts at a large angle during movement.

[0061] As Figures 5 to 9 shown, in an embodiment of the present disclosure, the guiding portion 270 may have an annular structure, and a guiding hole 2702 is formed in the middle of the guiding portion 270. The hole wall of the guiding hole 2702 is the above-mentioned guiding surface 2701 of the guiding portion 270, and the second valve needle 220 is inserted through the guiding hole 2702. In other words, the guiding surface 2701 in this embodiment surrounds the second valve needle 220 in the circumferential direction for one week. Furthermore, the flow passage 2105 may be provided in the guiding portion 270, and the flow passage 2105 axially penetrates the guiding portion 270. Through the above structural design, the present disclosure can provide a guiding function at each position in the circumferential direction of the second valve needle 220 by using the guiding portion 270, improve the guiding effect on the second valve needle 220, and further prevent the second valve needle 220 from tilting at a large angle during movement.

[0062] As Figures 5 to 9 shown, based on the structural design that the guiding portion 270 has an annular structure, in an embodiment of the present disclosure, the flow passage 2105 may be a through hole, that is, the flow passage 2105 has a complete (a full circle) inner wall in the circumferential direction, and the through hole and the guiding hole 2702 are arranged at intervals. Through the above structural design, the present disclosure utilizes the arrangement of the through hole and the guiding hole 2702 at intervals to avoid affecting the guiding function of the guiding hole 2702 for the second valve needle 220 at each position in the circumferential direction due to the setting of the through hole on the guiding portion 270, ensure a better guiding function, and at the same time optimize the structural rationality.

[0063] Referring to Figure 10 , Figure 10 FIG. shows a top view of the first valve needle 210 (such as the first assembly 211) of the electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment.

[0064] Different from Figures 6 to 9 the structural design in the shown embodiment where the guiding portion 270 is provided with one flow passage 2105, as Figure 10 shown, in another embodiment of the present disclosure, still taking the guiding portion 270 having an annular structure as an example, the guiding portion 270 may be provided with three flow passages 2105. Through the above structural design, the present disclosure can improve the balance of fluid flowing between the valve cavity 101 and the flow cavity 2101 through the flow passage 2105, and at the same time can make the force on the first valve needle 210 more uniform, further ensuring the force stability of the component. In some embodiments, the guiding portion 270 may also be provided with two, four or more than four flow passages 2105, which is not limited to this embodiment.

[0065] As Figure 10As shown, based on the structural design with at least two flow channels 2105 provided on the guiding portion 270, in another embodiment of the present disclosure, the at least two flow channels 2105 may be evenly distributed circumferentially. Through the above structural design, the present disclosure can further improve the balance of fluid flowing between the valve chamber 101 and the flow chamber 2101 via the flow channels 2105.

[0066] Refer to Figure 11 , Figure 11 FIG. shows a top view of the first valve needle 210 (e.g., the first assembly 211) of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment.

[0067] Different from Figures 6 to 9 or Figure 10 In the embodiment shown, the flow channel 2105 is designed as a through hole. As Figure 11 shown, in another embodiment of the present disclosure, the flow channel 2105 may be a through groove. The so-called "through" means that it penetrates the guiding portion 270 axially, and the so-called "groove" means that it opens on one side facing the guiding hole 2702 and communicates with the guiding hole 2702. In other words, the notch of the through groove communicates with the guiding hole 2702. In other words, the guiding hole 2702 and the through groove adopt an integrated channel structure. Through the above structural design, the present disclosure can reduce the structural complexity of the first valve needle 210 and facilitate processing.

[0068] As Figure 11 shown, and referring to Figure 5 simultaneously, in the above embodiment of the present disclosure, a transmission portion 221 may be provided on the outer periphery of the second valve needle 220. Specifically, the transmission portion 221 is located in the flow chamber 2101. Axially, the thickness of the transmission portion 221 is less than the height of the flow chamber 2101. On this basis, the driving assembly 400 can drive the second valve needle 220 to move away from the first valve port 1011, so that the transmission portion 221 abuts against the side wall of the flow chamber 2101 away from the first valve port 1011, so as to drive the first valve needle 210 to move away from the first valve port 1011.

[0069] Different from Figures 5 to 11 In the structural designs of the multiple embodiments shown, the guiding portion 270 has an annular structure. In an embodiment not shown in the present disclosure, the guiding portion 270 may also have a non-closed structure, such as an arc structure. Accordingly, in the circumferential direction, the portion not occupied by the guiding portion 270 between the second valve needle 220 and the opening of the flow chamber 2101 can form the flow channel 2105.

[0070] Based on the non-closed structural design of the guiding portion 270, in an embodiment not illustrated in the present disclosure, the valve core assembly 200 may include at least two guiding portions 270. The at least two guiding portions 270 are arranged at intervals in the circumferential direction and form at least two flow channels 2105 arranged at intervals in the circumferential direction.

[0071] Based on the non-closed structural design of the guiding portion 270, in an embodiment not illustrated in the present disclosure, the at least two guiding portions 270 may be evenly distributed in the circumferential direction.

[0072] As Figure 5 and Figure 6 shown, in an embodiment of the present disclosure, the first valve needle 210 may include a first assembly body 211 and a second assembly body 212. Specifically, the first assembly body 211 and the second assembly body 212 are assembled and connected, such as by crimping and sleeving, welding, etc. The first assembly body 211 is located on the side of the second assembly body 212 away from the first valve port 1011. On this basis, a groove may be provided on the side of the first assembly body 211 facing the first valve port 1011. The groove and the side of the second assembly body 212 facing away from the first valve port 1011 together form a flow cavity 2101, that is, the groove participates in forming at least part of the cavity of the flow cavity 2101. And, the flow channel 2105 is provided in the first assembly body 211, and the transverse channel 2103, the second valve port 2102, and the longitudinal channel 2104 are all provided in the second assembly body 212. Through the above structural design, the present disclosure can improve the structural rationality of the first valve needle 210. By using a smaller number of components and relatively simple component structures, the formation of each channel and cavity of the first valve needle 210 can be achieved, and the structure is relatively reasonable and convenient for processing and assembly.

[0073] It should be noted here that the electronic expansion valves shown in the drawings and described in this specification are only a few examples of the many electronic expansion valves that can adopt the principles of the present disclosure. It should be clearly understood that the principles of the present disclosure are by no means limited to any details of the electronic expansion valves shown in the drawings or described in this specification or any components of the electronic expansion valves.

[0074] In summary, the electronic expansion valve proposed in the present disclosure includes a valve seat assembly 100, a valve core assembly 200, and a driving assembly 400; a valve cavity 101 of the valve seat assembly 100 is provided with a first valve port 1011; the valve core assembly 200 includes a first valve needle 210 and a second valve needle 220; one end of the first valve needle 210 is in sealing fit with the first valve port 1011; the first valve needle 210 is provided with a flow cavity 2101 and a lateral channel 2103 extending radially, and the lateral channel 2103 communicates with the valve cavity 101; the flow cavity 2101 is provided with a second valve port 2102, one end of the second valve port 2102 communicates with the lateral channel 2103, and the other end communicates with the flow cavity 2101; a part of the second valve needle 220 is inserted into the flow cavity 2101, and one end of the second valve needle 220 facing the first valve port 1011 is in sealing fit with the second valve port 2102; a guiding surface 2701 matches the shape of at least part of the outer periphery of the second valve needle 220 to guide the second valve needle 220; the driving assembly 400 includes a screw 430, the screw 430 is connected to the second valve needle 220, and the screw 430 can drive the second valve needle 220 to move axially relative to the first valve needle 210. Through the above structural design, the present disclosure utilizes the guiding portion 270 to realize the guiding function for the second valve needle 220, avoid a large-angle inclination of the second valve needle 220 during movement, ensure the stability and reliability of the movement of the valve core assembly 200, and avoid leakage of the second valve port 2102 due to the inclination of the second valve needle 220 in the closed state.

[0075] The exemplary embodiments of the electronic expansion valve proposed in the present disclosure have been described in detail above and / or illustrated. However, the embodiments of the present disclosure are not limited to the specific embodiments described herein. On the contrary, each component and / or step of each embodiment can be used independently and separately from other components and / or steps described herein. Each component and / or each step of one embodiment can also be combined with other components and / or steps of other embodiments. When introducing the elements / components / etc. described and / or illustrated herein, the terms "a", "one", and "the above" etc. are used to indicate the existence of one or more elements / components / etc. The terms "comprising", "including", and "having" are used to mean an open inclusion and mean that there can be additional elements / components / etc. in addition to the listed elements / components / etc. Furthermore, the terms "first" and "second" etc. in the claims and the specification are only used as labels and are not numerical limitations on their objects.

[0076] Although the electronic expansion valve proposed in the present disclosure has been described according to different specific embodiments, those skilled in the art will recognize that modifications can be made to the implementation of the present disclosure within the spirit and scope of the claims.

Claims

1. An electronic expansion valve, characterized in that, Comprising: A valve seat assembly (100) having a valve cavity (101) formed therein, and the valve cavity (101) is provided with a first valve port (1011); A valve core assembly (200), including: A first valve needle (210) disposed in the valve cavity (101), one end of the first valve needle (210) being in sealing cooperation with the first valve port (1011); the first valve needle (210) is provided with a flow cavity (2101) and a lateral channel (2103) extending radially, and the lateral channel (2103) communicates with the valve cavity (101); the flow cavity (2101) is provided with a second valve port (2102), one end of the second valve port (2102) communicates with the lateral channel (2103), and the other end communicates with the flow cavity (2101); the first valve needle (210) is provided with a guiding portion (270), and the guiding portion (270) is located at the opening of the flow cavity (2101) and has a guiding surface (2701); and A second valve needle (220) partially inserted into the flow cavity (2101), one end of the second valve needle (220) facing the first valve port (1011) being in sealing cooperation with the second valve port (2102); the guiding surface (2701) is matched with the shape of at least a part of the outer periphery of the second valve needle (220) to guide the second valve needle (220); And A driving assembly (400), including a screw rod (430), the screw rod (430) being connected to the second valve needle (220), and the screw rod (430) being capable of driving the second valve needle (220) to move axially relative to the first valve needle (210) to achieve opening and closing control of the first valve port (1011) and the second valve port (2102).

2. The electronic expansion valve according to claim 1, characterized in that, A valve core sealing ring (213) is provided between the first valve needle (210) and the valve seat assembly (100), and the part of the valve cavity (101) located on the side of the valve core sealing ring (213) away from the first valve port (1011) is a back pressure cavity (1014); the first valve needle (210) is provided with a balance channel, and both ends of the balance channel communicate with the first valve port (1011) and the back pressure cavity (1014) respectively; the gap between the guiding surface (2701) and the second valve needle (220) communicates with the back pressure cavity (1014) and the flow cavity (2101) respectively.

3. The electronic expansion valve according to claim 2, characterized in that, The balance channel includes a flow channel (2105) and a longitudinal channel (2104) provided on the first valve needle (210), the flow cavity (2101) is located between the flow channel (2105) and the longitudinal channel (2104), and the flow channel (2105) communicates the flow cavity (2101) with the back pressure cavity (1014); the longitudinal channel (2104) communicates the first valve port (1011) with the flow cavity (2101).

4. The electronic expansion valve according to claim 3, characterized in that, In the circumferential direction, a portion of the second valve needle (220) that is not occupied by the guiding portion (270) between the second valve needle (220) and the opening of the flow cavity (2101) forms the flow channel (2105).

5. The electronic expansion valve according to claim 4, characterized in that, The valve core assembly (200) includes at least two guiding portions (270). The at least two guiding portions (270) are arranged at intervals in the circumferential direction and form at least two flow channels (2105) that are arranged at intervals in the circumferential direction.

6. The electronic expansion valve according to claim 5, wherein, The at least two guiding portions (270) are evenly distributed in the circumferential direction.

7. The electronic expansion valve according to claim 3, wherein, The guiding portion (270) has an annular structure. A guiding hole (2702) is formed in the middle of the guiding portion (270). The hole wall of the guiding hole (2702) is the guiding surface (2701). The second valve needle (220) passes through the guiding hole (2702). Among them, the flow channel (2105) is arranged on the guiding portion (270), and the flow channel (2105) axially penetrates the guiding portion (270).

8. The electronic expansion valve according to claim 7, characterized in that, The flow channel (2105) is a through hole, and the through hole is arranged at an interval from the guiding hole (2702).

9. The electronic expansion valve according to claim 7, characterized in that, The flow channel (2105) is a through groove, and the notch of the through groove communicates with the guiding hole (2702).

10. The electronic expansion valve according to claim 7, wherein, At least two flow channels (2105) are arranged on the guiding portion (270).

11. The electronic expansion valve according to claim 10, characterized in that, The at least two flow channels (2105) are evenly distributed in the circumferential direction.

12. The electronic expansion valve according to any one of claims 1 to 11, characterized in that, In the radial direction, the gap between the guiding surface (2701) of the guiding portion (270) and the outer circumference of the second valve needle (220) is less than or equal to 0.1 mm.

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