Electronic expansion valve

Abstract

The utility model provides an electronic expansion valve which comprises a valve seat assembly and a valve element assembly. A valve cavity of the valve seat assembly is provided with a first valve port; the valve element assembly comprises a first valve needle and a second valve needle. One end part of the first valve needle is in sealing fit with the first valve port; a circulation cavity, a transverse channel, a second valve port and a longitudinal channel are arranged in the first valve needle; the circulation cavity is located on the side, back to the first valve port, of the longitudinal channel. One end of the transverse channel is opened on the side of the first valve needle; one end of the second valve port communicates with the circulation cavity, and the other end communicates with the transverse channel; one end of the longitudinal channel is opened on the end face of the first valve needle facing the first valve port, and the other end is communicated with the circulation cavity; part of the second valve needle is inserted into the circulation cavity, and the end, facing the first valve port, of the second valve needle is in sealing fit with the second valve port.

Description

Technical Field

[0001] The present disclosure relates to the technical field of valves, and 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 disposed in the valve cavity of a 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 achieve the opening and closing of the large valve port. The large valve needle is provided with a transverse channel and a longitudinal channel. The large valve needle is also provided with a small valve port. The small valve needle is partially inserted into the large valve needle and is used to cooperate with the small valve port to achieve the opening and closing of the small valve port.

[0003] In the above existing solution, a valve needle cavity is provided inside the large valve needle. The valve needle cavity is provided with a small valve port. Two ends of the small valve port are respectively communicated with the valve needle cavity and the large valve port. In addition, a transverse channel is also provided inside the large valve needle. The fluid in the valve cavity can enter the valve needle cavity through the transverse channel. A balance channel axially penetrates the large valve needle. During use, to prevent the fluid in the valve needle cavity from flowing out of the large valve needle through the gap between the small valve needle and the large valve needle and the balance channel when the small valve port is in a closed state, resulting in the inability to cut off the fluid, a seal needs to be provided between the large valve needle and the small valve needle, and the setting of the seal often increases the overall processing difficulty.

[0004] Therefore, how to simplify the structural complexity of an electronic expansion valve adopting a dual-valve-needle design has become an important issue to be solved urgently in the related field. Summary of the Utility Model

[0005] 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 relatively simple structure.

[0006] To achieve the above object, the present disclosure adopts the following technical solutions:

[0007] 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 disposed in the valve cavity; one end of the first valve needle is in sealing cooperation with the first valve port; a flow cavity, a lateral channel, a second valve port, and a longitudinal channel are provided inside the first valve needle; the flow cavity is located on a side of the lateral channel and the longitudinal channel facing away from the first valve port; at least one end of the lateral channel opens on a side surface of the first valve needle; one end of the second valve port communicates with the flow cavity, and the other end communicates with the lateral channel; one end of the longitudinal channel opens on an end surface of the first valve needle facing the first valve port, and the other end communicates with the flow cavity; 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 driving assembly is configured to drive the first valve needle and the second valve needle to move axially to achieve opening and closing control of the first valve port and the second valve port.

[0008] According to one embodiment of the present disclosure, the first valve needle includes a first assembly body and a second assembly body that are separately provided and connected to each other. A groove is provided on a side of the first assembly body facing the first valve port, and the groove and a side of the second assembly body facing away from the first valve port together form the flow cavity; the lateral channel, the second valve port, and the longitudinal channel are provided in the second assembly body.

[0009] 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. A part of the valve cavity located on a side of the valve core sealing ring away from the first valve port is a back pressure cavity; a balance channel is provided on the first valve needle, and two ends of the balance channel communicate with the first valve port and the back pressure cavity respectively; the balance channel includes the longitudinal channel and a flow channel provided inside the first valve needle; one end of the flow channel communicates with the flow cavity, and the other end opens to communicate with the back pressure cavity.

[0010] According to one of the embodiments of the present disclosure, where: the valve core sealing ring is installed on the first valve needle; the circular area corresponding to the sealing area between the valve core sealing ring and the valve seat assembly is S1, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S1 = S3 + S4; or, the valve core sealing ring is installed on the valve seat assembly; the circular area corresponding to the sealing area between the valve core sealing ring and the first valve needle is S2, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S2 = S3 + S4.

[0011] According to one of the embodiments of the present disclosure, where: the valve core sealing ring is installed on the first valve needle; the circular area corresponding to the sealing area between the valve core sealing ring and the valve seat assembly is S1, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S1 < S3 + S4; or, the valve core sealing ring is installed on the valve seat assembly; the circular area corresponding to the sealing area between the valve core sealing ring and the first valve needle is S2, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S2 < S3 + S4.

[0012] According to one of the embodiments of the present disclosure, where: the valve core sealing ring is installed on the first valve needle; the circular area corresponding to the sealing area between the valve core sealing ring and the valve seat assembly is S1, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S1 > S3 + S4; or, the valve core sealing ring is installed on the valve seat assembly; the circular area corresponding to the sealing area between the valve core sealing ring and the first valve needle is S2, the circular area corresponding to the sealing area between the first valve needle and the first valve port is S3, and the circular area corresponding to the sealing area between the second valve needle and the second valve port is S4; wherein, S2 > S3 + S4.

[0013] According to one of the embodiments of the present disclosure, the first valve needle is provided with a through hole for the second valve needle to pass through; wherein, the flow passage is circumferentially connected to the through hole to form an integral hole structure.

[0014] According to one embodiment of the present disclosure, the sum of the flow areas of all the transverse channels is equal to the sum of the flow areas of all the longitudinal channels.

[0015] According to one embodiment of the present disclosure, the second valve port is located at the axial center position of the first valve needle, and the extending direction of the transverse channel is the radial direction of the first valve needle.

[0016] According to one embodiment of the present disclosure, the first valve needle is provided with at least one transverse channel, the transverse channel penetrates the first valve needle in the radial direction, both ends of the transverse channel are open to the side surface of the first valve needle, and the second valve port communicates with the middle position of the transverse channel.

[0017] According to one embodiment of the present disclosure, the number of the longitudinal channels on both sides of the transverse channel is equal; wherein, a reference plane parallel to the radial direction and perpendicular to the axial direction is defined, and on the reference plane, the orthographic projections of the longitudinal channels on both sides of the transverse channel are arranged axially symmetrically, and the axis of symmetry is the center line of the orthographic projection of the transverse channel.

[0018] According to one embodiment of the present disclosure, the electronic expansion valve further includes a first elastic member, and the first elastic member is connected between one end of the first valve needle facing away from the first valve port and the valve seat assembly; wherein, a receiving groove is provided at one end of the first valve needle facing away from the first valve port, and the first elastic member is partially received in the receiving groove.

[0019] According to one embodiment of the present disclosure, the electronic expansion valve further includes a second elastic member; wherein: the driving assembly includes a first screw rod and a spring sleeve; the second valve needle is fixedly connected with the spring sleeve, the spring sleeve is connected with the first screw rod in a limiting manner and can move axially relative to the spring sleeve; the second elastic member is located in the spring sleeve and between the second valve needle and the first screw rod; or, the electronic expansion valve further includes a support seat, the support seat is connected to the valve seat assembly; the driving assembly includes a second screw rod, the second elastic member is sleeved on the outer periphery of the second screw rod and is located between the support seat and the second screw rod.

[0020] According to one embodiment of the present disclosure, wherein: a first sealing structure is provided between one end of the first valve needle facing the first valve port and the first valve port, the first sealing structure includes a first sealing ring, and the material hardness of the first sealing ring is less than the material hardness of the first valve port; wherein, when the first valve port is closed, the first sealing ring contacts the first valve needle or the first valve port to achieve soft sealing; or, when the first valve port is closed, the first valve needle directly contacts the first valve port to achieve hard sealing.

[0021] According to one embodiment of the present disclosure, a transmission part is provided on the outer periphery of the second valve needle. The transmission part is integrally provided with the second valve needle. The transmission part is located in the flow passage cavity. Axially, the thickness of the transmission part is less than the height of the flow passage cavity. Wherein, the driving assembly drives the second valve needle to move away from the first valve port, so that the transmission part abuts against the side wall of the flow passage cavity away from the first valve port, thereby driving the first valve needle to move away from the first valve port.

[0022] According to one embodiment of the present disclosure, wherein: a second sealing ring is provided at the second valve port, and the material hardness of the second sealing ring is less than the material hardness of the second valve needle. Wherein, when the second valve port is closed, the second sealing ring is in contact with the second valve needle to achieve soft sealing; or, a sealing head is provided at one end of the second valve needle facing the first valve needle, and the material hardness of the sealing head is less than the material hardness of the second valve port. Wherein, when the second valve port is closed, the sealing head is in contact with the second valve port to achieve soft sealing; or, when the second valve port is closed, the second valve needle is in direct contact with the second valve port to achieve hard sealing.

[0023] 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:

[0024] The electronic expansion valve proposed in the present disclosure includes a valve seat assembly and a valve core assembly; the valve cavity of the valve seat assembly is provided with a first valve port; the valve core assembly includes a first valve needle and a second valve needle; one end of the first valve needle is sealed with the first valve port; a circulation cavity, a transverse channel, a second valve port and a longitudinal channel are provided inside the first valve needle; the circulation cavity is located on the side of the longitudinal channel facing away from the first valve port; one end of the transverse channel opens to the side of the first valve needle; one end of the second valve port is connected to the circulation cavity, and the other end is connected to the transverse channel; one end of the longitudinal channel opens to the end face of the first valve needle facing the first valve port, and the other end is connected to the circulation cavity; part of the second valve needle is inserted into the circulation cavity, and one end of the second valve needle facing the first valve port is sealed with the second valve port. Through the above design, when the second valve port is opened, the present disclosure can realize that the throttling refrigerant first flows through the circulation cavity of the first valve needle and then flows out of the first valve port, thereby making the second valve needle realize a non-internal balance structure. Compared with the existing solution that the small valve needle adopts the internal balance structure, the present disclosure can use the longitudinal channel as both the flow path and the balance channel, thereby avoiding the longitudinal channel from being blocked by the oil in the valve cavity. At the same time, the present disclosure adopts the above non-internal balance structure for the second valve needle, that is, the transverse channel, the second valve port, the circulation cavity and the longitudinal channel are connected in sequence, thereby forming a flow path for the fluid. On this basis, since one end of the second valve port opens toward the flow cavity rather than toward the first valve port, when the second valve port is closed, even if there is no seal between the second valve needle and the first valve needle, the fluid entering the first valve needle will be cut off by the second valve needle, ensuring that the flow of the second valve port is zero. Accordingly, it is possible to avoid setting an additional seal between the first valve needle and the second valve needle, reduce the number of parts of the electronic expansion valve, and reduce the complexity of the structure. Since the setting of the above-mentioned seal is avoided, the present invention does not need to weld the corresponding pressing plate, which can reduce the welding process and help improve the production efficiency of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various objects, features and advantages of the present disclosure will become more apparent by considering the following detailed description of preferred embodiments of the present disclosure in conjunction with the accompanying drawings. The accompanying drawings are merely exemplary illustrations of the present disclosure and are not necessarily drawn to scale. In the accompanying drawings, the same reference numerals always refer to the same or similar parts. Among them:

[0026] Figure 1 is a schematic diagram of a three-dimensional structure of an electronic expansion valve according to an exemplary embodiment;

[0027] Figure 2 yes Figure 1 Bottom view of

[0028] Figure 3 and Figure 4 Along Figure 2 The schematic cross-sectional view of the line AA and the line BB in FIG.

[0029] Figure 5 and Figure 6 respectively are Figure 3 and Figure 4 the enlarged schematic cross-sectional structure of the spool assembly shown;

[0030] Figure 7 is Figure 3 and Figure 4 the schematic perspective structure of the spool assembly shown;

[0031] Figure 8 is Figure 7 the schematic perspective structure of some components shown;

[0032] Figure 9 and Figure 10 respectively are Figure 8 the schematic perspective exploded views from two different perspectives;

[0033] Figure 11 is the schematic perspective structure of the second assembly of the electronic expansion valve shown according to another exemplary embodiment;

[0034] Figure 12 is the schematic cross-sectional view of the second assembly of the electronic expansion valve shown according to another exemplary embodiment;

[0035] Figure 13 is the schematic partial cross-sectional view of the electronic expansion valve shown according to another exemplary embodiment;

[0036] Figure 14 and Figure 15 respectively are the schematic cross-sectional views of the spool assembly of the electronic expansion valve shown according to two other exemplary embodiments;

[0037] Figure 16 is the schematic cross-sectional view of the electronic expansion valve shown according to another exemplary embodiment;

[0038] Figure 17 is Figure 16 the enlarged schematic view of part C in ;

[0039] Figure 18 is the schematic cross-sectional view of the electronic expansion valve shown according to another exemplary embodiment;

[0040] Figure 19 is Figure 18 the enlarged schematic view of part E in ;

[0041] Figure 20 is the schematic cross-sectional view of the electronic expansion valve shown according to another exemplary embodiment;

[0042] Figure 21 isFigure 20 An enlarged schematic view of the partial structure shown;

[0043] Figure 22 is Figure 20 A three-dimensional structure schematic diagram of the valve core assembly of the electronic expansion valve shown;

[0044] Figure 23 is Figure 22 A three-dimensional structure schematic diagram of the first assembly shown.

[0045] The description of the reference numerals is as follows:

[0046] 100. Valve seat assembly; 2104. Longitudinal channel; 250. Sliding part;

[0047] 101. Valve cavity; 2105. Flow channel; 260. Drainage trough body;

[0048] 1011. First valve port; 2106. Through hole; 261. Drainage hole;

[0049] 1012. First positioning surface; 2107. Accommodating groove; 270. Guide part;

[0050] 1013. Positioning protrusion; 211. First assembly; 2701. Guide surface;

[0051] 1014. Back pressure cavity; 212. Second assembly; 300. Guide seat;

[0052] 110. Valve core sleeve; 213. Valve core sealing ring; 3101. Second positioning surface;

[0053] 120. Valve cover; 220. Second valve needle; 400. Driving assembly;

[0054] 130. Support seat; 221. Transmission part; 410. First elastic part;

[0055] 200. Valve core assembly; 231. First sealing ring; 420. Second elastic part;

[0056] 210. First valve needle; 232. First pressing piece; 430. First screw;

[0057] 2101. Flow cavity; 241. Second sealing ring; 440. Spring sleeve;

[0058] 2102. Second valve port; 242. Sealing head; 450. Second screw;

[0059] 2103. Transverse channel; 243. Second pressing piece; 500. Outer shell. Specific embodiments

[0060] Exemplary embodiments embodying the features and advantages of the present disclosure will be described in detail below. 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 herein are for illustrative purposes in nature and not for limiting the present disclosure.

[0061] 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.

[0062] 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 a refrigeration system as an example. It is easy for those skilled in the art to understand 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 embodiments, and these changes are still within the scope of the principle of the electronic expansion valve proposed by the present disclosure.

[0063] 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 assembly 400. Referring in conjunction with Figures 2 to 9 , Figure 2 representatively shows the bottom view of Figure 1 ; Figure 3 representatively shows a cross-sectional schematic diagram taken along the straight line A-A in Figure 2 ; Figure 4 representatively shows a cross-sectional schematic diagram taken along the straight line B-B in Figure 2 ; Figure 5 representatively shows Figure 3 an enlarged schematic diagram of the cross-sectional structure of the valve core assembly 200 in Figure 6 ; Figure 4 representatively shows an enlarged schematic diagram of the cross-sectional structure of the valve core assembly 200 in Figure 7FIG. 0 schematically shows a perspective view of the valve spool assembly 200; Figure 8 FIG. 1 schematically shows Figure 7 a perspective view of some components shown (e.g., the second assembly 212 and the sealing head 242); Figure 9 and Figure 10 FIGS. 2A and 2B schematically show Figure 8 perspective exploded views in two different perspectives. The following will, in conjunction with the above drawings, detail the structures, connection manners, and functional relationships of the main components of the electronic expansion valve proposed in the present disclosure.

[0064] As Figures 1 to 9As shown, in an embodiment of the present disclosure, a valve cavity 101 is provided inside a 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, a transverse channel 2103, a second valve port 2102, and a longitudinal channel 2104 are provided inside the first valve needle 210. The flow cavity 2101 is located on the side of the transverse channel 2103 and the longitudinal channel 2104 facing away from the first valve port 1011. At least one end of the transverse channel 2103 opens on the side surface of the first valve needle 210. One end of the second valve port 2102 communicates with the flow cavity 2101, and the other end of the second valve port 2102 communicates with the transverse channel 2103. One end of the longitudinal channel 2104 opens on the end surface of the first valve needle 210 facing the first valve port 1011, and the other end of the longitudinal channel 2104 communicates with the flow cavity 2101. Accordingly, the longitudinal channel 2104 can be used as both a balance channel and a flow path. The second valve needle 220 is partially inserted into the flow cavity 2101. For example, during actual installation, the second valve needle 220 can be inserted outwards from the flow cavity 2101. 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 driving assembly 400 is used to drive the first valve needle 210 and the second valve needle 220 to move axially 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. Through the above design, when the second valve port 2102 is opened, the present disclosure can realize that the throttling refrigerant first flows through the flow cavity 2101 of the first valve needle 210 and then flows out of the first valve port 1011. Specifically, for example, the throttling refrigerant sequentially flows through the transverse channel 2103, the second valve port 2102, the flow cavity 2101, the longitudinal channel 2104, and the first valve port 1011 and flows out, which is the forward flow. The present disclosure can also realize the reverse flow. Specifically, the throttling refrigerant sequentially flows out through the first valve port 1011, the longitudinal channel 2104, the flow cavity 2101, the second valve port 2102, and the transverse channel 2103. Compared with the existing scheme in which a small valve needle adopts an internal balance structure, the present disclosure can use the longitudinal channel 2104 as both a flow path and a balance channel, thereby avoiding the longitudinal channel 2104 being blocked by the oil in the valve cavity 101. At the same time, the present disclosure connects the transverse channel 2103, the second valve port 2102, the flow cavity 2101, and the longitudinal channel 2104 in sequence to form a flow path for the fluid.On this basis, since one end of the second valve port 2102 opens towards the flow-through cavity 2101 instead of towards the first valve port 1011, when the second valve port 2102 is closed, even if there is no seal between the second valve needle 220 and the first valve needle 210, the fluid entering the first valve needle 210 will be cut off by the second valve needle 220, ensuring that the flow rate of the second valve port 2102 is zero. Based on this, it is possible to avoid setting an additional seal between the first valve needle 210 and the second valve needle 220, reduce the number of components of the electronic expansion valve, and lower the structural complexity. Since the above-mentioned seal is not provided, the present disclosure also does not require welding and fixing the corresponding pressing piece of the seal, which can reduce the welding process and is beneficial to improving the production efficiency of the product.

[0065] As Figures 5 to 7 shown, in an embodiment of the present disclosure, the first valve needle 210 includes a first assembly body 211 and a second assembly body 212 that are separately arranged and connected to each other. A groove is provided on the side of the first assembly body 211 facing the first valve port 1011, and the groove and the side of the second assembly body 212 facing away from the first valve port 1011 together form the above-mentioned flow-through cavity 2101. The lateral channel 2103, the second valve port 2102, and the longitudinal channel 2104 are provided in the second assembly body 212.

[0066] As Figures 3 to 7 shown, in an embodiment of the present disclosure, a valve core seal ring 213 may be provided between the first valve needle 210 and the valve seat assembly 100. The part of the valve cavity 101 located 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. The balance channel includes the above-mentioned longitudinal channel 2104 and a flow-through channel 2105 provided in the first valve needle 210. One end of the flow-through channel 2105 is communicated with the flow-through cavity 2101, and the other end of the flow-through channel 2105 opens and is communicated with the back pressure cavity 1014. Through the above design, the present disclosure can achieve the internal balance structure design of the first valve needle 210, and communicate the back pressure cavity 1014 with the first valve port 1011 through the balance channel, thereby reducing the acting force of the fluid on the first valve needle 210.

[0067] In an embodiment of the present disclosure, the first assembly 211 and the second assembly 212 can be connected by, for example, crimping socket connection, welding, etc., and the first assembly 211 is located on the side of the second assembly 212 away from the first valve port 1011. On this basis, the transverse channel 2103, the second valve port 2102, and the longitudinal channel 2104 are all provided in the second assembly 212. Through the above design, the present disclosure can further improve the structural rationality of the first valve needle 210. By using a relatively small number of components and relatively simple component structures, the formation of each channel and cavity of the first valve needle 210 can be realized, and the structure is relatively reasonable, which is convenient for processing and assembly.

[0068] In an embodiment of the present disclosure, the valve core seal ring 213 can be installed on the first valve needle 210, for example, in cooperation with Figure 5 and Figure 6 As shown, the valve core seal ring 213 is installed in the seal groove provided on the outer periphery of the first valve needle 210. At this time, the circular area corresponding to the seal area between the valve core seal ring 213 and the valve seat assembly 100 is defined as S1. In addition, the circular area corresponding to the seal area between the first valve needle 210 and the first valve port 1011 is defined as S3, and the circular area corresponding to the seal area between the second valve needle 220 and the second valve port 2102 is defined as S4. Then, S1 = S3 + S4. In other embodiments not illustrated in the present disclosure, the valve core seal ring 213 can also be installed on the valve seat assembly 100. At this time, the circular area corresponding to the seal area between the valve core seal ring 213 and the first valve needle 210 is defined as S2. On this basis, still taking the above definitions of S3 and S4 as examples, then S2 = S3 + S4. Based on the above design, the valve core assembly 200 can be used in both forward and reverse directions, that is, for two-way flow. The above relationship can make the fluid force received by the first valve needle 210 on the basis of the internal balance design approach zero, avoiding the fluid at the inlet and outlet of the electronic expansion valve from exerting a force on the first valve needle 210 and preventing the first valve needle 210 in the closed state from being lifted due to a relatively large force.

[0069] Different from the design of the above area relationship, in other embodiments of the present disclosure, designs with other area relationships can also be adopted. For example, when the fluid of the electronic expansion valve enters from the side and exits from the bottom (i.e., forward fluid), the circular area corresponding to the sealing area between the first valve needle 210 and the first valve port 1011 (i.e., S3 above) can be increased. On this basis, taking the valve core sealing ring 213 being installed on the first valve needle 210 as an example, then S1 < S3 + S4. Or, taking the valve core sealing ring 213 being installed on the valve seat assembly 100 as an example, then S2 < S3 + S4. Through the above design, the present disclosure can enable the inlet and outlet fluid to generate a force on the first valve needle 210, and use this force to close the first valve port 1011 to avoid leakage of the first valve port 1011. Another example is that when the fluid of the electronic expansion valve enters from the bottom and exits from the side (i.e., reverse fluid), the circular area corresponding to the sealing area between the first valve needle 210 and the first valve port 1011 (i.e., S3 above) can be reduced. On this basis, taking the valve core sealing ring 213 being installed on the first valve needle 210 as an example, then S1 > S3 + S4. Or, taking the valve core sealing ring 213 being installed on the valve seat assembly 100 as an example, then S2 > S3 + S4. Through the above design, the present disclosure can also enable the inlet and outlet fluid to generate a force on the first valve needle 210, and use this force to close the first valve port 1011 to avoid leakage of the first valve port 1011.

[0070] As Figure 7 shown, in an embodiment of the present disclosure, the first valve needle 210 can be provided with a through hole 2106 through which the second valve needle 220 can pass. On this basis, the flow passage 2105 of the first valve needle 210 and the through hole 2106 can be connected in the circumferential direction to form an integral channel structure. Through the above design, since the flow passage 2105 and the through hole 2106 adopt an integral channel structure, the present disclosure can simplify the structural complexity of the first valve needle 210 and reduce the processing difficulty. On this basis, while the present disclosure uses the flow passage 2105 to connect the valve cavity 101 and the flow cavity 2101, it can prevent the second valve needle 220 from entering the flow passage 2105, ensure the cooperation between the second valve needle 220 and the through hole 2106, and improve the stability and reliability of the relative movement between the second valve needle 220 and the first valve needle 210.

[0071] As Figure 7As shown, based on the design that the first valve needle 210 is provided with a through hole 2106 and the through hole 2106 and the flow passage 2105 form an integral channel structure, in an embodiment of the present disclosure, the first valve needle 210 may be provided with at least two flow passages 2105, such as, but not limited to, the two flow passages 2105 shown in the drawings, and these flow passages 2105 may be evenly distributed along the circumferential direction of the through hole 2106. Through the above design, the present disclosure can improve the balance of fluid flowing between the valve cavity 101 and the flow cavity 2101 via 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.

[0072] In an embodiment of the present disclosure, the flow area of the transverse channel 2103 may be equal to the flow area of the longitudinal channel 2104, ensuring the consistency of the forward and reverse flow curves during forward and reverse flow. Specifically, the above relationship of the flow areas is for the comparison of all the transverse channels 2103 and all the longitudinal channels 2104, that is, the sum of the flow areas of all the transverse channels 2103 (when there is one transverse channel 2103, it is the flow area of a single transverse channel 2103) is equal to the sum of the flow areas of all the longitudinal channels 2104 (when there is one longitudinal channel 2104, it is the flow area of a single transverse channel 2103).

[0073] As Figures 3 to 6 shown, in an embodiment of the present disclosure, the second valve port 2102 may be located at the axial center position of the first valve needle 210. On this basis, the extending direction of the transverse channel 2103 may be the radial direction of the first valve needle 210. In some embodiments, the second valve port 2102 may also be located at other positions of the first valve needle 210. On this basis, the extending direction of the transverse channel 2103 may be the radial direction of the first valve needle 210, or may also be other directions perpendicular to the axial direction.

[0074] As Figures 3 to 6 shown, based on the design that the extending direction of the transverse channel 2103 is the radial direction, in an embodiment of the present disclosure, the first valve needle 210 may be provided with at least one transverse channel 2103, and at least one transverse channel 2103 penetrates the first valve needle 210 along the radial direction, that is, both ends of at least one transverse channel 2103 are open to the side surface of the first valve needle 210, and the second valve port 2102 communicates with the middle position of this transverse channel 2103. In other words, for the above transverse channel 2103 that penetrates the first valve needle 210 along the radial direction, it can also be understood as two transverse channels 2103, the extending directions of the two are the same, and the opposite ends of the two are respectively open to the side surface of the first valve needle 210, and the facing ends of the two are connected together and jointly form the second valve port 2102.

[0075] As Figures 3 to 6As shown, based on the design that the extending direction of the transverse channel 2103 is radial, in an embodiment of the present disclosure, the first valve needle 210 may be provided with a transverse channel 2103, that is, a transverse channel 2103 that penetrates the first valve needle 210 along the radial direction. On this basis, a longitudinal channel 2104 may be provided on each side of the transverse channel 2103. In other words, since the transverse channel 2103 penetrates the first valve needle 210 along the radial direction, the first valve needle 210 is divided into two partial regions in the circumferential direction by the transverse channel 2103. Accordingly, the present disclosure may provide a longitudinal channel 2104 in each region. Through the above design, the present disclosure can improve the balance of fluid flow. In some embodiments, when the first valve needle 210 is provided with a transverse channel 2103 that penetrates along the radial direction, two or more longitudinal channels 2104 may also be respectively provided on both sides of the transverse channel 2103, and the number of longitudinal channels 2104 provided on both sides of the transverse channel 2103 may be, but is not limited to, equal.

[0076] As Figures 2 to 6 shown, based on the design that at least one longitudinal channel 2104 is provided on each side of the transverse channel 2103, in an embodiment of the present disclosure, the number of longitudinal channels 2104 located on both sides of the transverse channel 2103 may be equal. For example, but not limited to, as shown in the drawings, both are one. On this basis, a reference plane parallel to the radial direction and perpendicular to the axial direction is defined. On this reference plane, the orthographic projections of the longitudinal channels 2104 located on both sides of the transverse channel 2103 may be arranged axially symmetrically, and the axis of symmetry is the center line of the orthographic projection of the transverse channel 2103. Through the above design, the present disclosure can further improve the balance of fluid flow.

[0077] Refer to Figure 11 , Figure 11 which representatively shows a three-dimensional structural schematic diagram of a second assembly 212 of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment.

[0078] Different from Figures 2 to 6 the embodiment shown in which one longitudinal channel 2104 is provided on each side of the transverse channel 2103, as Figure 11 shown, in another embodiment of the present disclosure, still taking the first valve needle 210 being provided with a transverse channel 2103 that penetrates along the radial direction as an example, the first valve needle 210 may be provided with four longitudinal channels 2104. These four longitudinal channels 2104 are distributed in pairs on both sides of the transverse channel 2103, and with the center line of the orthographic projection of the transverse channel 2103 as the axis of symmetry, the orthographic projections of the four longitudinal channels 2104 are arranged axially symmetrically in pairs.

[0079] Refer to Figure 12 , Figure 12Fig. 0 shows a cross-sectional schematic view of a second assembly 212 of an electronic expansion valve capable of embodying the principles of the present disclosure in another exemplary embodiment.

[0080] Different from Figures 2 to 6 the design in the illustrated embodiment where the transverse channel 2103 penetrates the first valve needle 210 radially, as Figure 12 shown, in another embodiment of the present disclosure, still taking the extension direction of the transverse channel 2103 as the radial direction of the first valve needle 210 as an example, the transverse channel 2103 may not penetrate the first valve needle 210, that is, only one end of the transverse channel 2103 opens on the side surface of the first valve needle 210. Specifically, one end of the transverse channel 2103 opens on the side surface of the first valve needle 210, and the other end of the transverse channel 2103 communicates with the second valve port 2102.

[0081] As Figure 12 shown, based on the design that the transverse channel 2103 does not penetrate the first valve needle 210, in another embodiment of the present disclosure, the first valve needle 210 may be provided with three transverse channels 2103. One end of each of these three transverse channels 2103 opens on the side surface of the first valve needle 210 respectively, and the other ends of the three transverse channels 2103 converge at one place (such as the axis center of the first valve needle 210) and jointly communicate with the second valve port 2102. In some embodiments, the first valve needle 210 may also be provided with two, four or more than four transverse channels 2103 that do not penetrate the first valve needle 210, and are not limited to the above embodiments.

[0082] As Figure 12 shown, based on the design that one end of at least two transverse channels 2103 jointly communicates with the second valve port 2102, in another embodiment of the present disclosure, at least two transverse channels 2103 may be evenly arranged along the circumferential direction of the first valve needle 210. Through the above design, the present disclosure can make the fluid force received by the second valve needle 220 laterally more uniform, and make the overall resultant force of the fluid force smaller, reducing the influence of the fluid force on the second valve needle 220.

[0083] As Figure 12As shown, based on the design that the transverse channels 2103 do not penetrate the first valve needle 210, in another embodiment of the present disclosure, longitudinal channels 2104 may be provided between any two adjacent transverse channels 2103. In other words, since the extending direction of the transverse channels 2103 is the radial direction of the first valve needle 210, at least two transverse channels 2103 that meet at one end each divide the first valve needle 210 into at least two partial regions in the circumferential direction (for example, the three partial regions shown in the accompanying drawings). Accordingly, the present disclosure can provide a longitudinal channel 2104 in each region. Through the above design, the present disclosure can improve the balance of fluid flow. In some embodiments, when the first valve needle 210 is provided with at least two non-penetrating transverse channels 2103, two or more longitudinal channels 2104 may be respectively provided in at least two partial regions separated by the at least two transverse channels 2103 of the first valve needle 210, and the number of longitudinal channels 2104 provided in each partial region may or may not be equal.

[0084] As Figure 12 shown, based on the design that the transverse channels 2103 do not penetrate the first valve needle 210, in another embodiment of the present disclosure, the first valve needle 210 may be provided with at least three transverse channels 2103, such as but not limited to the three transverse channels 2103 shown in the accompanying drawings. These transverse channels 2103 may be evenly spaced along the circumferential direction of the first valve needle 210, and a longitudinal channel 2104 is provided between any two adjacent transverse channels 2103, and the longitudinal channels 2104 are evenly distributed in the circumferential direction of the first valve needle 210. Through the above design, the present disclosure can further improve the balance of fluid flow. It should be noted that when the first valve needle 210 is provided with two non-penetrating transverse channels 2103 and the two transverse channels 2103 are evenly arranged along the circumferential direction, that is, the extending directions of the two transverse channels 2103 are the same and can form a structure similar to the transverse channels 2103 in the embodiment Figures 3 to 6 shown.

[0085] As Figure 3 and Figure 4As shown, in an embodiment of the present disclosure, the electronic expansion valve proposed by the present disclosure may further include a first elastic member 410, and the first elastic member 410 is connected between one end of the first valve needle 210 facing away from the first valve port 1011 and the valve seat assembly 100 (for example, the cavity wall of the valve cavity 101 away from the first valve port 1011). On this basis, a receiving groove 2107 may be provided at one end of the first valve needle 210 (for example, the above-mentioned first assembly 211) facing away from the first valve port 1011, and a part of the first elastic member 410 is received in the receiving groove 2107. Through the above design, the present disclosure can use the compensation of the first elastic member 410 to achieve the sealing of the first valve port 1011 in the open state of the second valve port 2102. On this basis, the present disclosure can arrange the first elastic member 410 by using the receiving groove 2107 to ensure the installation space of the first elastic member 410, and at the same time ensure that the first valve needle 210 has a certain length in the axial direction, so as to ensure that the first valve needle 210 has enough length for guiding cooperation with the valve seat assembly 100 (for example, the valve core sleeve 110).

[0086] As Figure 3 and Figure 4 shown, in an embodiment of the present disclosure, the electronic expansion valve proposed by the present disclosure may further include a second elastic member 420. Specifically, the driving assembly 400 includes a first screw 430 and a spring sleeve 440. The second valve needle 220 is fixedly connected to the spring sleeve 440, and the spring sleeve 440 is limitedly connected to the first screw 430 and can move axially relative to the spring sleeve 440. The second elastic member 420 is located inside the spring sleeve 440 and between the second valve needle 220 and the first screw 430. After the second valve port 2012 is closed, the first screw 430 moves relative to the second valve needle 220 in a direction close to the second valve port 2012, the compression degree of the second elastic member 420 increases, and the second valve needle 220 presses against the second valve port 2012.

[0087] As Figure 16 shown, in another embodiment of the present disclosure, after the second valve port 2012 is closed, the first screw 430 moves relative to the second valve needle 220 in a direction away from the second valve port 2012, the compression degree of the second elastic member 420 increases, and the second valve needle 220 presses against the second valve port 2012.

[0088] As Figures 3 to 8As shown, in an embodiment of the present disclosure, one end of the first valve needle 210 facing the first valve port 1011 may be provided with a first sealing structure. The first sealing structure includes a first sealing ring 231, and the material hardness of the first sealing ring 231 is less than that of the first valve port 1011. On this basis, when the first valve port 1011 is closed, the first sealing ring 231 is in contact with the first valve port 1011 to achieve soft sealing. In some embodiments, still taking the design in which soft sealing is achieved between the first valve needle 210 and the first valve port 1011 by providing the first sealing ring 231 as an example, the first sealing structure including the first sealing ring 231 may also be provided at the first valve port 1011. Accordingly, when the first valve port 1011 is closed, the first sealing ring 231 is in contact with the first valve needle 210 to achieve soft sealing.

[0089] As Figure 5 , Figure 6 , Figure 9 and Figure 10 shown, based on the design in which the first sealing ring 231 is provided on the first valve needle 210, in an embodiment of the present disclosure, the first sealing structure may further include a first pressing piece 232. The first pressing piece 232 is used to press against the first sealing ring 231 and assemble it at the first valve needle 210. Among them, the first pressing piece 232 may be connected to the first valve needle 210 by means of welding or riveting.

[0090] Referring to Figure 13 , Figure 13 shows a partial cross-sectional schematic diagram of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment.

[0091] Different from Figures 3 to 6 the embodiment shown in which soft sealing is adopted between the first valve needle 210 and the first valve port 1011, as Figure 13 shown, in another embodiment of the present disclosure, when the first valve port 1011 is closed, the first valve needle 210 and the first valve port 1011 may be in direct contact, that is, hard sealing is provided between the first valve needle 210 and the first valve port 1011.

[0092] It should be noted that in some embodiments of the present disclosure, regardless of whether soft sealing or hard sealing is involved between the first valve needle 210 and the first valve port 1011, the sealing and mating portion of the first valve port 1011 and the first valve needle 210 may be provided with a structure in the shape of a taper chamfer or an arc chamfer. The above chamfered design may refer to the shapes of the first valve needle 210 and the first valve port 1011, or may also refer to the shape of the first sealing ring 231 and its sealing and mating portion.

[0093] As Figure 5 and Figure 6As shown, in one embodiment of the present disclosure, a transmission part 221 may be provided on the outer periphery of the second valve needle 220. Specifically, the transmission part 221 is integrally provided with the second valve needle 220, and the transmission part 221 is located in the circulation cavity 2101. In the axial direction, the thickness of the transmission part 221 is less than the height of the circulation cavity 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 part 221 abuts against a side cavity wall of the circulation cavity 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.

[0094] like Figures 5 to 7 As shown, based on the design that the second valve needle 220 is provided with the transmission part 221, in one embodiment of the present disclosure, when the first valve needle 210 is provided with a through hole 2106 (i.e., a guide hole provided by the guide part 270) and the through hole 2106 and the circulation channel 2105 (e.g., a through groove design) adopt an integrated channel structure, the shape of the transmission part 221 can match the shape of the channel structure, that is, during the assembly process of the valve core assembly 200, part of the second valve needle 220 passes through the circulation cavity 2101, and the maximum outer diameter of the transmission part 221 is smaller than the inner diameter of the through hole 2106, thereby ensuring that the part of the second valve needle 220 provided with the transmission part 221 will not axially escape from the circulation cavity 2101. Through the above design, the present disclosure can reduce the assembly difficulty of the valve core assembly 200 and improve the assembly efficiency.

[0095] like Figure 5 , Figure 6 , Figure 8 and Figure 9 As shown, in one embodiment of the present disclosure, a sealing head 242 may be provided at one end of the second valve needle 220 facing the first valve needle 210, and the material hardness of the sealing head 242 is less than the material hardness of the second valve port 2102. On this basis, when the second valve port 2102 is closed, the sealing head 242 contacts the second valve port 2102 to achieve a soft seal.

[0096] like Figure 5 and Figure 6As shown, based on the design in which the sealing head 242 is provided on the second valve needle 220, in an embodiment of the present disclosure, a second pressing piece 243 may further be provided at one end of the second valve needle 220 facing the first valve needle 210. The second pressing piece 243 is used to press against the sealing head 242 to assemble it on the second valve needle 220. Among them, the second pressing piece 243 and the sealing head 242 are riveted and fixed. Further, the axial side cross-section of the sealing head 242 may be generally in a "T" shape and have a horizontal portion and a vertical portion. The horizontal portion is pressed by the second pressing piece 243 at one end of the second valve needle 220 facing the first valve port 1011. The second pressing piece 243 is generally annular and surrounds the vertical portion. One end of the vertical portion is connected to the horizontal portion, and the other end extends axially toward the second valve port 2102. The sealing head 242 is in sealing cooperation with the second valve port 2102 with the vertical portion.

[0097] Referring to Figure 14 , Figure 14 , a cross-sectional schematic view of the valve core assembly 200 of an electronic expansion valve that can embody the principles of the present disclosure in another exemplary embodiment is representatively shown.

[0098] Different from Figure 5 and Figure 6 In the embodiment shown, the axial side cross-section of the sealing head 242 is designed to be in a "T" shape. As Figure 14 shown, in an embodiment of the present disclosure, still taking the second valve needle 220 provided with the sealing head 242 as an example, the side of the sealing head 242 facing the second valve port 2102 may also be planar. For example, the axial side cross-section of the sealing head 242 is rectangular. On this basis, the sealing head 242 is in sealing cooperation with the second valve port 2102 with the side plane facing the second valve port 2102. Further, the second valve port 2102 may be provided with a sealing protrusion protruding axially toward the second valve needle 220, and the second valve port 2102 penetrates through the sealing protrusion. Accordingly, the second valve port 2102 facilitates the sealing cooperation between the sealing protrusion and the above-mentioned plane of the sealing head 242, and is not limited to the above-mentioned embodiment.

[0099] Referring to Figure 15 , Figure 15 , a cross-sectional schematic view of the valve core assembly 200 of an electronic expansion valve that can embody the principles of the present disclosure in another exemplary embodiment is representatively shown.

[0100] As Figure 15 shown, in an embodiment of the present disclosure, one end of the second valve port 2102 facing the second valve needle 220 may be provided with a second sealing structure. The second sealing structure includes a second sealing ring 241. The material hardness of the second sealing ring 241 is less than the material hardness of the second valve needle 220. On this basis, when the second valve port 2102 is closed, the second sealing ring 241 contacts the second valve needle 220 to achieve soft sealing.

[0101] AsFigure 15 As shown, based on the design in which the second sealing ring 241 is provided at the second valve port 2102, in an embodiment of the present disclosure, the second sealing structure may further include a second pressing piece 243, and the second pressing piece 243 is used to press against the second sealing ring 241 to assemble it at the second valve port 2102.

[0102] Different from Figures 3 to 6 or Figures 14 to 15 In the embodiment shown, a soft sealing design is adopted for the second valve needle 220 and the second valve port 2102. As Figure 13 shown, in another embodiment of the present disclosure, when the second valve port 2102 is closed, the second valve needle 220 and the second valve port 2102 can be in direct contact, that is, a hard seal is provided between the second valve needle 220 and the second valve port 2102.

[0103] Referring to Figure 16 and Figure 17 , Figure 16 FIG. shows a cross-sectional schematic diagram of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment; Figure 17 FIG. representatively shows Figure 16 an enlarged schematic diagram of part C in

[0104] As Figure 16 and Figure 17 shown, in an embodiment of the present disclosure, the electronic expansion valve proposed by the present disclosure further includes a guide seat 300. Specifically, at least a part of the guide seat 300 is disposed in the valve cavity 101 of the valve seat assembly 100 and is fixedly connected to the valve seat assembly 100. The material hardness of the guide seat 300 is less than the material hardness of the valve seat assembly 100. On this basis, a first positioning surface 1012 is provided on the cavity wall of the valve cavity 101. The first positioning surface 1012 faces the guide seat 300 and is located on the side of the guide seat 300 facing the first valve port 1011. The guide seat 300 has a second positioning surface 3101 facing the first positioning surface 1012. Among them, a positioning protrusion 1013 is provided on the first positioning surface 1012. Accordingly, the positioning protrusion 1013 presses against the guide seat 300 (for example, the second positioning surface 3101), causing the guide seat 300 with relatively low material hardness to deform, so as to realize the positioning function of the valve seat assembly 100 and the guide seat 300 in the axial and circumferential directions. Through the above structural design, the present disclosure can use the positioning protrusion 1013 to press against the valve seat assembly 100 or the guide seat 300 to cause it to deform. Accordingly, the deformed guide seat 300 and the valve seat assembly 100 are in a circumferential limit fit, avoiding relative rotation or relative axial displacement between the guide seat 300 and the valve seat assembly 100, and realizing reliable positioning of the guide seat 300.

[0105] It should be noted that in an embodiment not illustrated in the present disclosure, the material hardness of the guide seat 300 may also be greater than that of the valve seat assembly 100. On this basis, the positioning protrusion 1013 may be provided on the guide seat 300, that is, the positioning protrusion 1013 is located on the second positioning surface 3101. Accordingly, the positioning protrusion 1013 presses against the valve seat assembly 100 (such as the first positioning surface 1012), causing the valve seat assembly 100 with relatively small material hardness to deform, thereby realizing the positioning function of the valve seat assembly 100 and the guide seat 300 in the axial and circumferential directions. In other words, in various possible embodiments that conform to the design concept of the present disclosure, the material hardness of the guide seat 300 is different from that of the valve seat assembly 100, and among the two, the one with the greater material hardness is provided with the positioning protrusion 1013. The positioning protrusion 1013 is located on the first positioning surface 1012 or the second positioning surface 3101, and the positioning protrusion 1013 presses against the other one of the valve seat assembly 100 and the guide seat 300 (that is, the one with relatively small material hardness).

[0106] As Figure 16 shown, in an embodiment of the present disclosure, the electronic expansion valve proposed by the present disclosure may further include a second elastic member 420. Specifically, the electronic expansion valve further includes a support seat 130, and the support seat 130 is connected to the valve seat assembly 100. The driving assembly 400 includes a second screw 450, and the second elastic member 420 is sleeved on the outer periphery of the second screw 450 and is located between the support seat 130 and the second screw 450.

[0107] Referring to Figure 18 and Figure 19 , Figure 18 FIG. shows a cross-sectional view of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment; Figure 19 FIG. shows representatively Figure 18 an enlarged view of part E in

[0108] As Figure 18 and Figure 19As shown, in an embodiment of the present disclosure, the valve core assembly 200 further includes a drainage groove body 260. Specifically, the drainage groove body 260 is disposed on the outer periphery of the first valve needle 210. The notch of the drainage groove body 260 faces the first valve needle 210 and is closed by the first valve needle 210. Drainage holes 261 are provided on the groove wall of the drainage groove body 260. The transverse channel 2103 communicates with the valve cavity 101 via the cavity of the drainage groove body 260 and the drainage holes 261. Through the above design, since the transverse channel 2103 can communicate with the valve cavity 101 via the cavity of the drainage groove body 260 and the drainage holes 261, the fluid can flow through the drainage holes 261 to the cavity of the drainage groove body 260, and then flow through the cavity of the drainage groove body 260 to the transverse channel 2103. Due to the presence of the drainage groove body 260, the present disclosure does not need to arrange the drainage holes 261 in one-to-one correspondence with the transverse channels 2103, thereby reducing the processing difficulty of arranging the transverse channels 2103 in the valve core assembly 200 and improving the convenience of processing.

[0109] In an embodiment of the present disclosure, the drainage groove body 260 may be in the shape of an annular groove structure, and the drainage groove body 260 is arranged around the outer periphery of the first valve needle 210. Through the above structural design, the present disclosure can make the flow of the fluid into each transverse channel 2103 via the drainage groove body 260 more uniform.

[0110] Refer to Figures 20 to 23 , Figure 20 FIG. shows a cross-sectional schematic view of an electronic expansion valve that can embody the principle of the present disclosure in another exemplary embodiment; Figure 21 FIG. typically shows Figure 20 an enlarged schematic view of a partial structure shown in Figure 22 FIG. typically shows Figure 20 a three-dimensional structural schematic view of the valve core assembly 200 shown in Figure 23 FIG. typically shows a three-dimensional structural schematic view of the first assembly 211.

[0111] As Figures 20 to 23As shown, in an embodiment of the present disclosure, the first valve needle 210 is provided with a guiding portion 270. The guiding portion 270 is located at the opening of the flow cavity 2101 and has a guiding surface 2701. The guiding surface 2701 matches the shape of at least a part of the outer periphery of the second valve needle 220 to guide the second valve needle 220. The gap between the guiding surface 2701 and the second valve needle 220 communicates the above-mentioned back pressure cavity 1014 with the flow cavity 2101 (which can also be communicated via the flow channel 2105). The driving assembly 400 includes a first screw 430. The first screw 430 is connected to the second valve needle 220, and the first screw 430 can drive the second valve needle 220 to move axially relative to the first valve needle 210. Through the above design, the present disclosure utilizes the guiding portion 270 to achieve the guiding function of the second valve needle 220, avoiding a large-angle inclination of the second valve needle 220 during movement and ensuring the stability and reliability of the movement of the valve core assembly 200.

[0112] The gap between the guiding surface 2701 and the second valve needle 220 communicates the above-mentioned back pressure cavity 1014 with the flow cavity 2101, that is, there is no sealing structure between the second valve needle 220 and the first valve needle 210, and the second valve needle 220 is a non-inner balance structure. Due to the adoption of the above non-inner balance structure, the first valve needle 210 of the present disclosure can avoid setting an additional sealing ring between the first valve needle 210 and the second valve needle 220, reduce the number of components of the electronic expansion valve, and lower the structural complexity. Since the above-mentioned sealing ring is not provided, the present disclosure also does not need to weld the corresponding pressing piece, which can reduce the welding process and is beneficial to improving the production efficiency of the product. On this basis, compared with the existing solution, when the additional sealing ring between the first valve needle 210 and the second valve needle 220 is removed, the second valve needle 220 is more likely to have a large-angle inclination during movement. In this regard, through the guiding function of the guiding portion 270, the present disclosure can further meet the guiding requirements for the second valve needle 220 in this case, which is beneficial to the specific implementation of the design of removing the additional sealing ring. Of course, the design of the valve core assembly 200 of the present disclosure can also adopt the above-mentioned inner balance structure design. At this time, through the guiding function of the guiding portion 270, the present disclosure can still improve the guiding effect on the second valve needle 220 and further reduce the possibility of a large-angle inclination during its movement.

[0113] 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 or any components of the electronic expansion valves shown in the drawings or described in this specification.

[0114] In summary, the electronic expansion valve proposed by the present disclosure includes a valve seat assembly 100 and a valve core assembly 200; a first valve port 1011 is provided in a valve cavity 101 of the valve seat assembly 100; 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 cooperation with the first valve port 1011; a flow cavity 2101, a transverse channel 2103, a second valve port 2102, and a longitudinal channel 2104 are provided inside the first valve needle 210; the flow cavity 2101 is located on a side of the longitudinal channel 2104 facing away from the first valve port 1011; one end of the transverse channel 2103 opens on a side surface of the first valve needle 210; one end of the second valve port 2102 communicates with the flow cavity 2101, and the other end communicates with the transverse channel 2103; one end of the longitudinal channel 2104 opens on an end surface of the first valve needle 210 facing the first valve port 1011, 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 cooperation with the second valve port 2102. Through the above design, when the second valve port 2102 is opened, the present disclosure can achieve that the throttling refrigerant first flows through the flow cavity 2101 of the first valve needle 210 and then flows out of the first valve port 1011. Specifically, for example, the throttling refrigerant flows through the transverse channel 2103, the second valve port 2102, the flow cavity 2101, the longitudinal channel 2104, and the outflow path of the first valve port 1011 in sequence. Accordingly, the second valve needle 220 realizes a non-internal balance structure. Compared with the existing scheme in which a small valve needle adopts an internal balance structure, the present disclosure can use the longitudinal channel 2104 as both a flow path and a balance channel at the same time, thereby avoiding the longitudinal channel 2104 being blocked by the oil in the valve cavity 101. At the same time, the present disclosure connects the transverse channel 2103, the second valve port 2102, the flow cavity 2101, and the longitudinal channel 2104 in sequence to form a flow path of the fluid. On this basis, since one end of the second valve port 2102 opens towards the flow cavity 2101 instead of towards the first valve port 1011, when the second valve port 2102 is closed, even if there is no seal between the second valve needle 220 and the first valve needle 210, the fluid entering the first valve needle 210 will be cut off by the second valve needle 220, ensuring that the flow rate of the second valve port 2102 is zero flow rate. Accordingly, it is possible to avoid arranging an additional seal between the first valve needle 210 and the second valve needle 220, reduce the number of parts of the electronic expansion valve, and reduce the structural complexity. Since the above-mentioned seal is avoided, the present disclosure also does not need to weld and fix the corresponding pressing piece of the seal, can reduce the welding process, and is beneficial to improving the production efficiency of the product.

[0115] Exemplary embodiments of the electronic expansion valve proposed by the present disclosure have been described and / or illustrated in detail above. However, the embodiments of the present disclosure are not limited to the specific embodiments described herein. On the contrary, the components and / or steps of each embodiment can be used independently and separately from the other components and / or steps described herein. Each component and / or each step of one embodiment can also be used in combination with the other components and / or steps of other embodiments. When introducing the elements / components / etc. described and / or illustrated herein, the terms "a", "an", 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 may be additional elements / components / etc. in addition to the listed elements / components / etc. In addition, 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.

[0116] Although the electronic expansion valve proposed by 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 embodiments 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) with a valve cavity (101) formed inside, and a first valve port (1011) is provided in the valve cavity (101); 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) is in sealing cooperation with the first valve port (1011); a flow cavity (2101), a transverse channel (2103), a second valve port (2102), and a longitudinal channel (2104) are provided inside the first valve needle (210); the flow cavity (2101) is located on the side of the transverse channel (2103) and the longitudinal channel (2104) facing away from the first valve port (1011); at least one end of the transverse channel (2103) opens on the side surface of the first valve needle (210); one end of the second valve port (2102) communicates with the flow cavity (2101), and the other end communicates with the transverse channel (2103); one end of the longitudinal channel (2104) opens on the end surface of the first valve needle (210) facing the first valve port (1011), and the other end communicates with the flow cavity (2101); and A second valve needle (220) 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); and A driving assembly (400) for driving the first valve needle (210) and the second valve needle (220) to move axially to control the opening and closing of the first valve port (1011) and the second valve port (2102).

2. The electronic expansion valve according to claim 1, wherein The first valve needle (210) includes a first assembly body (211) and a second assembly body (212) which are separately arranged and connected to each other. A groove is provided on the side of the first assembly body (211) facing the first valve port (1011), and the groove and the side of the second assembly body (212) facing away from the first valve port (1011) together form the flow cavity (2101); the transverse channel (2103), the second valve port (2102), and the longitudinal channel (2104) are provided in the second assembly body (212).

3. The electronic expansion valve according to claim 1, characterized in that, 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) located on the side of the valve core seal 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 the two ends of the balance channel communicate with the first valve port (1011) and the back pressure cavity (1014) respectively; the balance channel includes the longitudinal channel (2104) and a flow channel (2105) provided in the first valve needle (210); one end of the flow channel (2105) communicates with the flow cavity (2101), and the other end opens to communicate with the back pressure cavity (1014).

4. The electronic expansion valve according to claim 3, characterized in that: The valve core sealing ring (213) is installed on the first valve needle (210); the circular area corresponding to the sealing area between the valve core sealing ring (213) and the valve seat assembly (100) is S1, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S1 = S3 + S4; or, The valve core sealing ring (213) is installed on the valve seat assembly (100); the circular area corresponding to the sealing area between the valve core sealing ring (213) and the first valve needle (210) is S2, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S2 = S3 + S4.

5. The electronic expansion valve according to claim 3, characterized in that: The valve core sealing ring (213) is installed on the first valve needle (210); the circular area corresponding to the sealing area between the valve core sealing ring (213) and the valve seat assembly (100) is S1, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S1 < S3 + S4; or, The valve core sealing ring (213) is installed on the valve seat assembly (100); the circular area corresponding to the sealing area between the valve core sealing ring (213) and the first valve needle (210) is S2, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S2 < S3 + S4.

6. The electronic expansion valve according to claim 3, characterized in that: The valve core sealing ring (213) is installed on the first valve needle (210); the circular area corresponding to the sealing area between the valve core sealing ring (213) and the valve seat assembly (100) is S1, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S1 > S3 + S4; or, The spool seal ring (213) is installed on the valve seat assembly (100); the circular area corresponding to the sealing area between the spool seal ring (213) and the first valve needle (210) is S2, the circular area corresponding to the sealing area between the first valve needle (210) and the first valve port (1011) is S3, and the circular area corresponding to the sealing area between the second valve needle (220) and the second valve port (2102) is S4; wherein, S2 > S3 + S4.

7. The electronic expansion valve according to claim 3, wherein The first valve needle (210) is provided with a through hole (2106) through which the second valve needle (220) passes; wherein, the flow passage (2105) and the through hole (2106) are connected in the circumferential direction to form an integral channel structure.

8. The electronic expansion valve according to claim 1, characterized in that, The sum of the flow areas of all the transverse channels (2103) is equal to the sum of the flow areas of all the longitudinal channels (2104).

9. The electronic expansion valve according to claim 1, characterized in that, The second valve port (2102) is located at the axial center position of the first valve needle (210), and the extending direction of the transverse channel (2103) is the radial direction of the first valve needle (210).

10. The electronic expansion valve according to claim 9, characterized in that, The first valve needle (210) is provided with at least one transverse channel (2103) that penetrates the first valve needle (210) in the radial direction. Both ends of the transverse channel (2103) open to the side surface of the first valve needle (210), and the second valve port (2102) communicates with the middle position of the transverse channel (2103).

11. The electronic expansion valve according to claim 10, wherein, The number of the longitudinal channels (2104) on both sides of the transverse channel (2103) is equal; wherein, a reference plane parallel to the radial direction and perpendicular to the axial direction is defined. On the reference plane, the positive projections of the longitudinal channels (2104) on both sides of the transverse channel (2103) are arranged axially symmetrically, and the axis of symmetry is the center line of the positive projection of the transverse channel (2103).

12. The electronic expansion valve according to any one of claims 1 to 11, characterized in that, The electronic expansion valve further includes a first elastic member (410) connected between the end of the first valve needle (210) facing away from the first valve port (1011) and the valve seat assembly (100); wherein, a receiving groove (2107) is provided at the end of the first valve needle (210) facing away from the first valve port (1011), and a part of the first elastic member (410) is received in the receiving groove (2107).

13. The electronic expansion valve according to any one of claims 1 to 11, characterized in that, The electronic expansion valve further includes a second elastic member (420); wherein: The driving assembly (400) includes a first screw (430) and a spring sleeve (440); the second valve needle (220) is fixedly connected to the spring sleeve (440), and the spring sleeve (440) is connected to the first screw (430) in a limiting manner and can move axially relative to the spring sleeve (440); the second elastic member (420) is located inside the spring sleeve (440) and between the second valve needle (220) and the first screw (430); or, The electronic expansion valve further includes a support base (130), and the support base (130) is connected to the valve seat assembly (100); the driving assembly (400) includes a second screw rod (450), and the second elastic member (420) is sleeved on the outer periphery of the second screw rod (450) and is located between the support base (130) and the second screw rod (450).

14. The electronic expansion valve according to any one of claims 1 to 11, characterized in that: A first sealing structure is provided between one end of the first valve needle (210) facing the first valve port (1011) and the first valve port (1011), and the first sealing structure includes a first sealing ring (231), and the material hardness of the first sealing ring (231) is less than the material hardness of the first valve port (1011); wherein, when the first valve port (1011) is closed, the first sealing ring (231) is in contact with the first valve needle (210) or the first valve port (1011) to achieve soft sealing; or, When the first valve port (1011) is closed, the first valve needle (210) is in direct contact with the first valve port (1011) to achieve hard sealing.

15. The electronic expansion valve according to any one of claims 1 to 11, characterized in that, A transmission part (221) is provided on the outer periphery of the second valve needle (220), the transmission part (221) is integrally provided with the second valve needle (220), the transmission part (221) is located in the flow cavity (2101), and along the axial direction, the thickness of the transmission part (221) is less than the height of the flow cavity (2101); wherein, the driving assembly (400) drives the second valve needle (220) to move away from the first valve port (1011), so that the transmission part (221) abuts against the side wall of the flow cavity (2101) away from the first valve port (1011) to drive the first valve needle (210) to move away from the first valve port (1011).

16. The electronic expansion valve according to any one of claims 1 to 11, characterized in that: A second sealing ring (241) is provided at the second valve port (2102), and the material hardness of the second sealing ring (241) is less than the material hardness of the second valve needle (220); wherein, when the second valve port (2102) is closed, the second sealing ring (241) is in contact with the second valve needle (220) to achieve soft sealing; or, A sealing head (242) is provided at one end of the second valve needle (220) facing the first valve needle (210), and the material hardness of the sealing head (242) is less than the material hardness of the second valve port (2102); wherein, when the second valve port (2102) is closed, the sealing head (242) is in contact with the second valve port (2102) to achieve soft sealing; or, When the second valve port (2102) is closed, the second valve needle (220) is in direct contact with the second valve port (2102) to achieve hard sealing.

Images