Electronic expansion valve and assembly method

Abstract

An electronic expansion valve and assembly method are disclosed. The electronic expansion valve includes a valve needle assembly (10) and a valve seat assembly, the valve seat assembly having a second valve chamber (33) and a valve port chamber (34) communicating with each other, the valve needle assembly includes a valve core (14), the valve core has a locking segment (1421), the valve needle assembly is movably inserted into the valve seat assembly to regulate the flow rate of fluid flowing through the valve port chamber, and the locking segment locks into the bottom wall of the second valve chamber. The electronic expansion valve makes it possible to make the radial dimensions of the closing ring formed by multiple valve seat assemblies having valve port chambers of different radial dimensions and the locking segment of the same valve core all the same, and while ensuring the closed position, it becomes possible to replace valve seat assemblies with valve port chambers of different radial dimensions, or to adjust the radial dimensions of the closing ring by replacing the valve needle assembly and / or valve seat assembly, the disassembly, assembly and adjustment of the electronic expansion valve is made easier, and the processing efficiency and applicability of the electronic expansion valve are improved.

Description

Technical Field

[0001] This application claims the priority of a patent application filed with the China National Intellectual Property Administration on June 6, 2023, with the application number 202310664114.5 and the title "Electronic Expansion Valve".

[0002] This application relates to the technical field of electronic expansion valves, and specifically to electronic expansion valves and assembly methods.

Background Art

[0003] In the prior art, when the valve needle assembly closes the valve port, the radial dimension of the closing ring formed between the valve needle assembly and the valve port is usually the same as the radial dimension of the valve port. It can be understood that the closing position of the valve needle assembly in the prior art relative to the valve port is usually located on the valve port.

[0004] When it is necessary to perform adaptive disassembly, assembly, and adjustment on the electronic expansion valve, that is, when it is necessary to replace the valve port size of the electronic expansion valve, the valve seat assembly and the valve needle assembly need to be replaced simultaneously, and a closing ring needs to be formed between the valve needle assembly and the valve port to ensure the closing effect. This means that the valve needle assembly and the valve seat assembly need to be correspondingly replaced, increasing the frequency of disassembly and assembly of the electronic expansion valve. At the same time, due to the corresponding relationship between the valve ports of the valve needle assembly and the valve seat assembly, it is necessary to perform corresponding processing on both of them as a set during processing, increasing the processing cost of the valve needle assembly and the valve seat assembly.

Summary of the Invention

Problems to be Solved by the Invention

[0005] This application provides an electronic expansion valve and an assembly method, and solves the problem that in the prior art, when replacing different valve seats of the valve port according to various situations, the sealing member between the valve needle assembly and the guide seat also needs to be replaced simultaneously.

Means for Solving the Problems

[0006] To solve the above problems, according to one aspect of the present application, the present application provides an electronic expansion valve comprising a valve needle assembly and a valve seat assembly, wherein the valve seat assembly has a second valve chamber and a valve port chamber communicating with each other, the valve needle assembly comprises a valve core, the valve core has a locking segment, the valve needle assembly is movably inserted within the valve seat assembly to regulate the flow rate of fluid flowing through the valve port chamber, and the locking segment locks into the bottom wall of the second valve chamber.

[0007] Furthermore, the valve seat assembly includes a guide seat and a valve seat, the valve seat having a first valve chamber, a second valve chamber and a valve port chamber that are sequentially in communication and through each other, the guide seat is inserted into the valve seat and separates the first valve chamber and the second valve chamber, the valve needle assembly and / or valve seat have a flow passage, the first valve chamber and the valve port chamber are in communication via the flow passage, the valve needle assembly penetrates the guide seat and engages tightly with the inner wall of the guide seat.

[0008] Furthermore, the second valve chamber and valve port chamber each have a locking chamber segment and a valve port segment on their opposing sides, the locking chamber segment and the valve port segment are in communication, the radial dimension of the locking chamber segment is larger than the radial dimension of the valve port segment, and the locking segment engages with the annular edge of the locking chamber segment that connects to the bottom wall of the second valve chamber.

[0009] Furthermore, the valve seat assembly includes a guide seat and a valve seat, the valve seat includes a seat body and a valve seat, the seat body and valve seat are detachably connected, the guide seat is inserted into the seat body, and the locking chamber segment and valve opening segment are located in the valve seat, or the locking chamber segment and valve opening segment are located in the seat body.

[0010] Furthermore, the guide seat is provided separately from the seat body, and either engages with the seat body for positional control, or the guide seat is provided integrally with the seat body.

[0011] Furthermore, the locking chamber segment is a frustoconical segment, the radial dimension of the locking chamber segment gradually decreases in the direction toward the valve opening segment, the side of the locking segment facing the valve opening chamber has an annular locking bevel for locking engagement with the locking chamber segment, the annular locking bevel and the locking chamber segment have the same inclination direction, the angle between the annular locking bevel and the axis of the valve core is greater than the angle between the locking chamber segment and the axis of the valve core, and the annular edge connecting the locking chamber segment and the bottom wall of the second valve chamber locks and engages with the annular locking bevel.

[0012] Furthermore, the locking chamber segment is a cylindrical segment, and the side of the locking segment facing the valve chamber has an annular locking slope for locking engagement with the locking chamber segment, and the annular edge connecting the locking chamber segment and the bottom wall of the second valve chamber locks with the annular locking slope.

[0013] Furthermore, the valve core includes a detachably connected seal segment and a closure segment, the seal segment engaging tightly with the inner wall of the valve seat assembly, and the closure segment includes a locking segment and a flow control segment connected to the locking segment, the radial dimension of the locking segment being greater than the radial dimension of the flow control segment, and the flow control segment engaging with the valve port chamber in a positional limiting manner.

[0014] Furthermore, the sealing segment and the blocking segment each have an engagement projection and an engagement groove on their adjacent sides, and the engagement projection engages with the engagement groove in a positional limiting manner.

[0015] Furthermore, the valve seat assembly or valve core has an annular seal groove, and the electronic expansion valve further includes an annular seal ring, which is positioned within the annular seal groove and engages sealantly with the valve core and valve seat assembly, respectively.

[0016] Furthermore, if the second valve chamber has a locking chamber segment on the side facing the valve port chamber, and the valve seat assembly has an annular seal groove, then the inner circumference of the annular seal ring engages with the valve core in a sealed manner, and if the inner diameter of the annular seal ring is D1 and the radial dimension of the closure ring formed by the contact between the valve core and the locking chamber segment is D2, then 1 ≤ D2 / D1 ≤ 1.05, or if the valve core has an annular seal groove, then the outer circumference of the annular seal ring engages with the valve seat assembly in a sealed manner, and if the outer diameter of the annular seal ring is D1 and the radial dimension of the closure ring formed by the contact between the valve core and the locking chamber segment is D2, then 1 ≤ D2 / D1 ≤ 1.05.

[0017] Furthermore, the electronic expansion valve further includes a casing and a drive assembly, the casing being connected to the valve seat, the drive assembly being located within the casing, the end of the drive assembly facing the guide seat engaging with the guide seat in a positional locking engagement and connected to the valve seat, and the valve needle assembly being sequentially inserted within the drive assembly, guide seat and valve seat.

[0018] Furthermore, the valve needle assembly further includes a screw, a connecting member and an elastic member, one end of the screw being connected to the drive assembly, the other end of the screw being connected to the valve core via the connecting member, the connecting member being movably positioned within a guide seat and engaging in positional reinforcing engagement with the inner wall of the guide seat, one end of the elastic member being in contact with the valve core, and the other end of the elastic member being in contact with the screw and / or the connecting member.

[0019] According to another embodiment of this application, an assembly method is provided that can be applied to the valve seat assembly of the electronic expansion valve described above, the assembly method comprising the steps of preparing a plurality of valve seats, wherein the radial dimensions of the plurality of closing rings formed by the contact of a locking segment with the bottom walls of a plurality of second valve chambers are the same, and the radial dimensions of the plurality of valve opening chambers are different, and selecting one suitable valve seat from among them as needed and connecting it to a guide seat.

[0020] By applying the technical solution of this application, an electronic expansion valve is provided, which includes a valve needle assembly and a valve seat assembly, the valve seat assembly having a second valve chamber and a valve port chamber communicating with each other, the valve needle assembly including a valve core, the valve core having a locking segment, the valve needle assembly being movably inserted within the valve seat assembly to regulate the flow rate of fluid flowing through the valve port chamber, and the locking segment locking into the bottom wall of the second valve chamber.

[0021] In this solution, the locking segment of the valve needle assembly engages with the bottom wall of the second valve chamber located above the valve port chamber to form a closure ring. By adopting this solution and positioning the closure position where the valve needle assembly closes the valve port chamber on the bottom wall of the second valve chamber, the conventional method of positioning the closure position where the valve needle assembly closes the valve port chamber directly within the valve port chamber, which results in the radial dimension of the valve port chamber becoming the radial dimension of the closure ring formed by the two, is avoided. The locking segment adjusts the closure position of the valve needle assembly relative to the valve port chamber upward, expanding it outward from the valve port chamber, and makes the radial dimension of the formed closure ring larger than the radial dimension of the valve port chamber. This makes it easy to make the radial dimensions of the closing ring, formed by multiple valve seat assemblies with valve chambers of different radial dimensions and locking segments of the same valve core, all the same. This allows for the exchange of valve seat assemblies with valve chambers of different radial dimensions, while ensuring the closed position is maintained, or achieves the objective of adjusting the radial dimensions of the closing ring by exchanging the valve needle assembly and / or valve seat assembly. This facilitates the disassembly, assembly, and adjustment of the electronic expansion valve, improves the processing efficiency and applicability of the electronic expansion valve, and reduces the processing costs of the valve seat assembly and valve needle assembly.

[0022] The drawings in the specification, which constitute part of this application, are used to enhance the understanding of this application, and the exemplary embodiments and descriptions herein are for interpretive purposes only and do not improperly limit this application. [Brief explanation of the drawing]

[0023] [Figure 1]The schematic configuration diagram of the electronic expansion valve provided by Example 1 of the present application is shown. [Figure 2] The schematic configuration diagram of the valve seat in the electronic expansion valve of FIG. 1 is shown. [Figure 3] The partial enlarged view of FIG. 1 is shown. [Figure 4] The schematic configuration diagram of the guide seat in the electronic expansion valve of FIG. 1 is shown. [Figure 5] The schematic configuration diagram of the electronic expansion valve provided by Example 2 of the present application is shown. [Figure 6] The schematic configuration diagram of the electronic expansion valve provided by Example 3 of the present application is shown. [Figure 7] The partial enlarged view of FIG. 6 is shown. [Figure 8] The schematic configuration diagram of the electronic expansion valve provided by Example 4 of the present application is shown. [Figure 9] The schematic configuration diagram of the electronic expansion valve provided by Example 5 of the present application is shown. [Figure 10] The schematic configuration diagram of the electronic expansion valve provided by Example 6 of the present application is shown.

Mode for Carrying Out the Invention

[0024] Hereinafter, in conjunction with the drawings in the embodiments of the present application, the technical solution means in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only some of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only exemplary and is not intended to impose any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present application.

[0025] As shown in Figures 1 to 4, Embodiment 1 of the present application provides an electronic expansion valve comprising a valve needle assembly 10 and a valve seat assembly, the valve seat assembly having a second valve chamber 33 and a valve port chamber 34 communicating with each other, the valve needle assembly 10 comprising a valve core 14, the valve core 14 having a locking segment 1421, the valve needle assembly 10 being movably inserted within the valve seat assembly to regulate the flow rate of fluid flowing through the valve port chamber 34, and the locking segment 1421 locking into the bottom wall of the second valve chamber 33.

[0026] In this embodiment, the locking segment 1421 of the valve needle assembly 10 locks and engages with the bottom wall of the second valve chamber 33 located above the valve port chamber 34 to form a closing ring. By employing the electronic expansion valve of this embodiment and positioning the closing position where the valve needle assembly 10 closes the valve port chamber 34 on the bottom wall of the second valve chamber 33, it avoids the situation in the prior art where the closing position where the valve needle assembly 10 closes the valve port chamber 34 is directly positioned on the valve port chamber 34, and the radial dimension of the valve port chamber 34 becomes the radial dimension of the closing ring formed by the two. The locking segment 1421 adjusts the closing position of the valve needle assembly 10 relative to the valve port chamber 34 upward, expanding it to the outside of the valve port chamber 34, and the radial dimension of the formed closing ring becomes larger than the radial dimension of the valve port chamber 34, thereby preventing the valve port chamber 34 from having different radial dimensions. This makes it easy to make the radial dimensions of the closing ring formed by multiple existing valve seat assemblies and the locking segment 1421 of the same valve core 14 all the same, and, while ensuring that the closing position does not change, it becomes possible to replace different valve seat assemblies having valve port chambers 34 with different radial dimensions, or the objective of adjusting the radial dimensions of the closing ring by replacing the locking segment 1421 of the valve needle assembly 10 and / or the valve seat assembly is achieved, making disassembly, assembly and adjustment of the electronic expansion valve easier, improving the processing efficiency and applicability of the electronic expansion valve, and reducing the processing costs of the valve seat assembly and valve needle assembly 10.

[0027] As shown in Figures 1 to 4, the valve seat assembly includes a guide seat 20 and a valve seat 30, the valve seat 30 having a first valve chamber 32, a second valve chamber 33 and a valve port chamber 34 that are sequentially in communication with and pass through each other, the guide seat 20 is inserted into the valve seat 30 and isolates the first valve chamber 32 and the second valve chamber 33, the valve needle assembly 10 and / or the valve seat 30 have a flow passage 31, the first valve chamber 32 and the valve port chamber 34 are in communication via the flow passage 31, the valve needle assembly 10 passes through the guide seat 20 and engages with the inner wall of the guide seat 20 in a sealed manner.

[0028] In this embodiment, the valve core 14 and the guide seat 20 engage in a sealed manner to form a sealing ring, and the radial dimension of the sealing ring formed between the valve core 14 and the guide seat 20 matches the radial dimension of the closing ring. This makes it possible to make the radial dimension of the closing ring formed by multiple valve seats 30 with valve opening chambers 34 of different radial dimensions and the locking segment 1421 of the same valve core 14 the same, and to match the radial dimension of the sealing ring formed between the same set of valve cores 14 and guide seats 20. This eliminates the need to process multiple valve seats 30 to accommodate the sealing members between multiple valve needle assemblies 10 and guide seats 20, or to simultaneously replace the valve seat 30 and the corresponding sealing members between the valve needle assemblies 10 and guide seats 20 when processing or replacing the valve seats 30. As a result, a single sealing member can accommodate multiple valve seats 30 with valve opening chambers 34 of different radial dimensions, improving the processing efficiency of the electronic expansion valve, while also standardizing multiple parts, reducing non-standard products, and simplifying parts management.

[0029] Specifically, the flow passage 31 in this embodiment is provided in the valve seat 30, which facilitates the processing of the flow passage 31.

[0030] The guide seat 20 has through milling grooves on both sides, and the outer circumference of the guide seat 20 engages in positional control with the inner wall of the valve seat 30, with the gap between the guide seat 20 and the valve seat 30 being the milling grooves of the guide seat 20.

[0031] Selectively, the flow passage 31 is a flow hole and / or flow groove. The isolation of the first valve chamber 32 and the second valve chamber 33 mainly emphasizes that the first valve chamber 32 is cut off from a position where it directly communicates with the second valve chamber 33, and the isolation of the first valve chamber 32 and the second valve chamber 33 does not mean complete non-communication. In this embodiment, when the electronic expansion valve is in the open position, the first valve chamber 32 and the second valve chamber 33 communicate via the flow passage 31 and valve opening chamber 34, and when the electronic expansion valve is in the closed position, the first valve chamber 32 and the second valve chamber 33 do not communicate.

[0032] Specifically, if the product has different specifications depending on different flow curve requirements, the valve seat 30 has correspondingly multiple different specifications, and in another embodiment of this application, an assembly method is provided that is applicable to the valve seat assembly of the electronic expansion valve described above, the assembly method comprising the steps of preparing a plurality of valve seats 30, wherein the radial dimensions of the plurality of closing rings formed by the contact of the locking segment 1421 and the bottom walls of a plurality of second valve chambers 33 are the same, and the radial dimensions of the plurality of valve port chambers 34 are different, and selecting one suitable valve seat 30 from among them as needed and connecting it to the guide seat 20. With this configuration, the radial dimensions of the multiple closing rings formed by the bottom walls of the second valve chambers 33 in multiple valve seats 30 and the locking segments 1421 of the same valve needle assembly 10 are all the same, and the radial dimensions of the multiple closing rings all match the radial dimensions of the seal ring formed between the valve core 14 and the guide seat 20. In other words, the same set of valve needle assembly 10 and guide seat 20 can accommodate multiple valve seats 30 having valve chambers 34 with different radial dimensions. This eliminates the need to process a single seal member to correspond to a single valve seat 30 during manufacturing, and enables a single seal member to correspond to multiple valve seats 30. Furthermore, when installing the valve seat assembly, the one with the most suitable radial dimensions of the valve chamber 34 can be selected from among the multiple valve seats 30 as needed, and replaced and installed. This eliminates the need to further replace the seal member between the valve needle assembly 10 and guide seat 20 that fit the closing ring, thus improving the applicability and ease of manufacturing of the electronic expansion valve.

[0033] As shown in Figure 3, the second valve chamber 33 and valve port chamber 34 each have a locking chamber segment 331 and a valve port segment 341 on opposing sides, with the locking chamber segment 331 communicating with the valve port segment 341, and the radial dimension of the locking chamber segment 331 being larger than the radial dimension of the valve port segment 341, so that the locking segment 1421 locks and engages with the locking chamber segment 331. With this configuration, locking and engaging the locking segment 1421 with the locking chamber segment 331 forms a closing ring for closing the valve port segment 341, making it easy to determine the position of the formed closing ring, ensuring that the closing ring corresponds to a seal ring, and at the same time, making it easy to machine the locking segment 1421, the locking chamber segment 331 and the valve port segment 341 without affecting the radial dimension of the valve port segment 341.

[0034] As shown in Figures 1 to 3, the valve seat assembly includes a guide seat 20 and a valve seat 30, the valve seat 30 includes a seat body 35 and a valve seat 36, the seat body 35 and the valve seat 36 are detachably connected, and the guide seat 20 is inserted into the seat body 35. In this embodiment, the guide seat 20 and the seat body 35 are provided separately, and the locking chamber segment 331 and the valve opening segment 341 are located in the seat body 35. This configuration facilitates the machining of the seat body 35 and the valve seat 36, and improves the machining efficiency of the electronic expansion valve, as it is only necessary to replace the seat body 35 while ensuring that the formed closure ring corresponds to the seal ring when the product has different specifications according to different flow curve requirements.

[0035] Specifically, the locking chamber segment 331 is a frustoconical segment, the radial dimension of the locking chamber segment 331 gradually decreases in the direction toward the valve opening segment 341, the side of the locking segment 1421 facing the valve opening chamber 34 has an annular locking bevel for locking engagement with the locking chamber segment 331, the annular locking bevel and the locking chamber segment 331 have the same inclination direction, the angle between the annular locking bevel and the axis of the valve core 14 is greater than the angle between the locking chamber segment 331 and the axis of the valve core 14, and the annular edge connecting the locking chamber segment 331 and the bottom wall of the second valve chamber 33 locks and engages with the annular locking bevel. With this configuration, the position of the closure ring is determined to be at the connection point between the locking chamber segment 331 and the bottom wall of the second valve chamber 33, and the inclination angle between the annular locking slope and the locking chamber segment 331 ensures that the position of the closure ring is restricted. On the other hand, since the annular locking slope and the locking chamber segment 331 have the same inclination direction, it is possible to guide the fluid passing through, and at the same time, it becomes easier to process the locking chamber segment 331 and to expand the closure ring outward and adjust it upward.

[0036] As shown in Figure 3, the valve core 14 includes a detachably connected seal segment 141 and a closure segment 142. The seal segment 141 engages tightly with the inner wall of the guide seat 20 of the valve seat assembly, and the closure segment 142 includes a locking segment 1421 and a flow rate regulating segment 1422 connected to the locking segment 1421. The radial dimension of the locking segment 1421 is greater than the radial dimension of the flow rate regulating segment 1422, which engages with the valve port chamber 34. This configuration facilitates the creation of a sealed position between the valve core 14 and the guide seat 20, while simultaneously allowing for easy positional control of the valve core 14 by the locking segment 1421, and facilitating flow rate regulation of the fluid flowing through the valve port chamber 34 by the movement of the flow rate regulating segment 1422 relative to the valve port chamber 34.

[0037] Specifically, the seal segment 141 and the blocking segment 142 each have a locking projection 143 and a locking groove on their adjacent sides, and the locking projection 143 engages with the locking groove for positional control. This configuration facilitates the positioning and connection of the seal segment 141 and the blocking segment 142, and ensures the reliability of the connection between the seal segment 141 and the blocking segment 142. Furthermore, in the case of electronic expansion valves having different specifications depending on the requirements of different flow curves, the valve core 14 can accommodate different flow curve requirements by replacing the blocking segment 142. Specifically, when replacing the blocking segment 142, the operator can take measures to replace the locking segment 1421 and the flow control segment 1422 based on the actual situation. For example, they can replace it with a blocking segment 142 in which the flow control segment 1422 is different but the locking segment 1421 is the same, thereby changing only the flow control range. Normally, the locking segment 1421 is not modified to avoid affecting the dimensions of the closing ring formed by the locking segment 1421 and the bottom wall of the second valve chamber 33, and consequently, the effect on the movement of the valve core 14. Specifically, in this embodiment, the locking projection 143 is provided on the seal segment 141, and the locking groove is provided on the closing segment 142.

[0038] As shown in Figure 1, the guide seat 20 or valve core 14 of the valve seat assembly has an annular seal groove, and the electronic expansion valve further includes an annular seal ring 42, which is positioned within the annular seal groove and engages seally with the valve core 14 and the guide seat 20, respectively. This configuration facilitates the seally engaging between the guide seat 20 and the seal segment 141 of the valve core 14, and at the same time facilitates the isolation of the first valve chamber 32 and the second valve chamber 33.

[0039] In this embodiment, the annular seal groove is located on the guide seat 20 of the valve seat assembly, and on the side of the second valve chamber 33 facing the valve port chamber 34, it has a locking chamber segment 331 for locking engagement with a locking segment 1421. The inner circumference of the annular seal ring 42 engages tightly with the valve core 14 to form a seal ring. If the inner diameter of the annular seal ring 42 is D1 and the radial dimension of the closed ring formed by the contact between the valve core 14 and the locking chamber segment 331 is D2, then 1 ≤ D2 / D1 ≤ 1.05. With this configuration, the inner diameter of the annular seal ring 42 becomes the radial dimension of the seal ring, and by limiting D1 and D2, the situation in which the movement of the valve needle assembly 10 is obstructed by differential pressure can be effectively suppressed.

[0040] As shown in Figure 1, the electronic expansion valve further includes a casing 50 and a drive assembly 60, the casing 50 being connected to the valve seat 30, the drive assembly 60 being located inside the casing 50 with its end facing the guide seat 20 engaging in positional control with the guide seat 20 and connected to the valve seat 30, and the valve needle assembly 10 being sequentially inserted into the drive assembly 60, the guide seat 20 and the valve seat 30. With this configuration, the valve needle assembly 10 is driven by the drive assembly 60, making it easy to switch between opening and closing the electronic expansion valve. The assembly process of the electronic expansion valve in this embodiment includes at least the following steps: first, assembling the parts of the valve needle assembly 10 other than the closing segment 142 of the valve core 14; second, attaching a part of the assembled valve needle assembly 10 to the guide seat 20; subsequently, crimp welding the closing segment 142 to the end of the valve needle assembly 10 that penetrates the guide seat 20; and then crimping the connected valve needle assembly 10 together with the guide seat 20 into the valve seat 30.

[0041] In this embodiment, the electronic expansion valve further includes a first connecting pipe 71 and a second connecting pipe 72, the drive assembly 60 includes a nut assembly 61, the first connecting pipe 71 and the second valve chamber 33 are in communication, the second connecting pipe 72 and the valve port chamber 34 are in communication, the nut assembly 61 has a first balance hole and a second balance hole that connect the first valve chamber 32 and the cavity within the nut assembly 61, the first connecting pipe 71 and the second valve chamber 33 are always in communication and the pressure is P1, the second connecting pipe 72 and the valve port chamber 34 are in communication and the pressure is P2, and the pressure of the cavity surrounded by the nut assembly 61 and the valve needle assembly 10 The force is P3, P2 and P3 maintain a dynamic balance, the valve chamber 34 communicates with the cavity of the nut assembly 61 via the flow passage 31, the first valve chamber 32, the first balance hole, and the second balance hole, D3 is the minimum radial dimension of the communication passage between the cavity of P2 and the cavity of P3, in this embodiment D3 is the radial dimension of the second balance hole of the nut assembly 61 (i.e., the balance hole that communicates the internal cavity of the casing 50 with the internal cavity of the nut assembly 61), the flow mode from the first connecting pipe 71 to the second connecting pipe 72 is set as forward flow, and the reverse is set as reverse flow. The pressure calculation formula is F=PS. For positive flow, F downward = P3*[π*(D1 / 2)^2-π*(D3 / 2)^2]+P1*[π*(D2 / 2)^2-π*(D1 / 2)^2] and F upward = P2*[π*(D2 / 2)^2-π*(D3 / 2)^2]. The differential pressure calculation formula is F upward = P2*[π*(D2 / 2)^2-π The equation is *(D3 / 2)^2]-P3*[π*(D1 / 2)^2-π*(D3 / 2)^2]-P1*[π*(D2 / 2)^2-π*(D1 / 2)^2], and since S and D are proportional, in the following description, S in the equation can be replaced with D, and the equation can be simplified to F upward = P2(D2-D3)-P3(D1-D3)-P1(D2-D1).In the case of the forward flow, since P1≠P2 when the fluid is flowing, P1>P2. Assuming P2 = P3 and D1 = D2, we can obtain F = P1(D1 - D2)+P2(D2 - D1). That is, the differential pressure formula is F = P1*π*[(D1 - D2) / 2]^2+P2*π*[(D2 - D1) / 2]^2. When D1 = D2, the differential pressure F = 0. That is, the differential pressure received by the valve needle assembly 10 during the movement process is theoretically 0. In the case of the reverse flow, P2>P1. Taking the example of opening the valve, since the pressure of P2 is instantaneously released and decreased, at this time P2<P3. Assuming D1 = D2 at this time, the differential pressure F=(P2 - P3)(D1 - D3), and F becomes a negative value, resulting in a pressure difference. Therefore, to offset the above pressure difference, the relationship between D1 and D2 is limited, and the limited range is 1≦D2 / D1≦1.05. Summing up the above, limiting the range of D1 and D2 is beneficial to eliminating the differential pressure received by the valve needle assembly 10 during the movement process and improving the smoothness of valve opening and closing.

[0042] Specifically, the valve needle assembly 10 further includes a screw 11, a connecting member 12 and an elastic member 13. One end of the screw 11 is connected to the drive assembly 60, and the other end of the screw 11 is connected to the valve core 14 through the connecting member 12. The connecting member 12 is movably arranged in the guide seat 20 and is in position-regulating engagement with the inner wall of the guide seat 20. One end of the elastic member 13 abuts against the valve core 14, and the other end of the elastic member 13 abuts against the screw 11 and / or the connecting member 12. By configuring like this, it becomes easy for the drive assembly 60 to drive the valve needle assembly 10. At the same time, it is realized that the guide seat 20 accommodates and guides the valve needle assembly 10, and the reliability of the operation of the valve needle assembly 10 is ensured.

[0043] As shown in Figure 5, Embodiment 2 of this application provides an electronic expansion valve, the difference from Embodiment 1 being that the annular seal groove in this embodiment is located on the valve core 14, and in this case the outer circumference of the annular seal ring 42 engages tightly with the guide seat 20 to form a seal ring, if the outer diameter of the annular seal ring 42 is D1 and the radial dimension of the closing ring formed by the contact between the valve core 14 and the locking chamber segment 331 is D2, then 1 ≤ D2 / D1 ≤ 1.05. With this configuration, the outer diameter of the annular seal ring 42 becomes the radial dimension of the seal ring, and by limiting D1 and D2, the situation in which the movement of the valve needle assembly 10 is obstructed by differential pressure can be effectively suppressed.

[0044] As shown in Figures 6 and 7, Embodiment 3 of this application provides an electronic expansion valve, the difference from Embodiment 2 being that the locking chamber segment 331 in this embodiment is a cylindrical segment, and the side of the locking segment 1421 facing the valve chamber 34 has an annular locking slope for locking engagement with the locking chamber segment 331, and the annular edge connecting the locking chamber segment 331 and the bottom wall of the second valve chamber 33 locks into the annular locking slope. This configuration facilitates the machining of the locking chamber segment 331, the outward and upward expansion and adjustment of the closing ring, and the determination of the position of the closing ring. Another difference from Embodiment 2 is that the valve core 14 in this embodiment is integrally provided, thereby ensuring the overall structural strength of the valve core 14.

[0045] As shown in Figure 8, Embodiment 4 of this application provides an electronic expansion valve, the difference from Embodiment 3 being that the annular seal groove in this embodiment is located on the guide seat 20, in which case the inner circumference of the annular seal ring 42 engages tightly with the valve core 14 to form a seal ring, and if the inner diameter of the annular seal ring 42 is D1 and the radial dimension of the closing ring formed by the contact between the valve core 14 and the locking chamber segment 331 is D2, then 1 ≤ D2 / D1 ≤ 1.05. By configuring it in this way and limiting D1 and D2, the situation in which the movement of the valve needle assembly 10 is obstructed by differential pressure can be effectively suppressed.

[0046] As shown in Figure 9, Embodiment 5 of this application provides an electronic expansion valve, the difference from Embodiment 3 being that the locking chamber segment 331 and the valve opening segment 341 in this embodiment are located in the valve section 36. With this configuration, if the product has different specifications according to different flow curve requirements, it is only necessary to replace the valve section 36 while ensuring that the formed closing ring corresponds to the sealing ring, thereby improving the manufacturing efficiency of the electronic expansion valve.

[0047] As shown in Figure 10, Embodiment 6 of this application provides an electronic expansion valve, the difference from Embodiment 5 being that the guide seat 20 and the seat body 35 are integrally provided. This configuration ensures the coaxiality of both, and consequently, the coaxiality of the connected components such as the casing 50, nut assembly 61, and valve seat 36, thereby ensuring the reliability of the electronic expansion valve.

[0048] The foregoing describes preferred embodiments of this application and is not intended to limit it. To those skilled in the art, this application is subject to various modifications and changes. Any modifications, equivalent substitutions, improvements, etc., made within the scope of the intent and principles of this application should be included within the scope of protection. [Explanation of Symbols]

[0049] 10 Valve needle assembly 11 Screw 12 Connecting members 13 Elastic members 14 valve cores 141 Seal Segment 142 Blockage Segments 1421 Locking segment 1422 Flow Control Segment 143 Attachment protrusion 20 Guide Seats 30 valve seats 31 Distribution aisle 32 First valve chamber 33 Second valve chamber 331 Locking Room Segment 34 valve chambers 341 Valve orifice segment 35 Seat Body 36 Lawyer's Account 42 Annular seal ring 50 Casing 60 Drive Assembly 61 Nut Assembly 71 First connecting pipe 72 Second connecting pipe

Claims

1. An electronic expansion valve comprising a valve needle assembly (10) and a valve seat assembly, wherein the valve seat assembly has a second valve chamber (33) and a valve port chamber (34) communicating with each other, the valve needle assembly (10) includes a valve core (14), the valve core (14) has a locking segment (1421), the valve needle assembly (10) is movably inserted within the valve seat assembly to regulate the flow rate of fluid flowing through the valve port chamber (34), and the locking segment (1421) locks into the bottom wall of the second valve chamber (33).

2. The electronic expansion valve according to claim 1, wherein the valve seat assembly includes a guide seat (20) and a valve seat (30), the valve seat (30) having a first valve chamber (32), a second valve chamber (33), and a valve port chamber (34) that are sequentially in communication and penetrate each other, the guide seat (20) is inserted into the valve seat (30) to isolate the first valve chamber (32) and the second valve chamber (33), the valve needle assembly (10) and / or the valve seat (30) have a flow passage (31), the first valve chamber (32) and the valve port chamber (34) are in communication via the flow passage (31), the valve needle assembly (10) penetrates the guide seat (20) and engages in a sealed manner with the inner wall of the guide seat (20).

3. The electronic expansion valve according to claim 1, characterized in that the second valve chamber (33) and the valve port chamber (34) each have a locking chamber segment (331) and a valve port segment (341) on opposing sides, the locking chamber segment (331) and the valve port segment (341) are in communication, the radial dimension of the locking chamber segment (331) is larger than the radial dimension of the valve port segment (341), and the locking segment (1421) locks and engages with an annular edge of the locking chamber segment (331) that is connected to the bottom wall of the second valve chamber (33).

4. The electronic expansion valve according to claim 3, wherein the valve seat assembly includes a guide seat (20) and a valve seat (30), the valve seat (30) includes a seat body (35) and a valve seat (36), the seat body (35) and the valve seat (36) are detachably connected, the guide seat (20) is inserted into the seat body (35), and the locking chamber segment (331) and the valve opening segment (341) are located in the valve seat (36), or the locking chamber segment (331) and the valve opening segment (341) are located in the seat body (35).

5. The electronic expansion valve according to claim 4, characterized in that the guide seat (20) is provided separately from the seat body (35), and the guide seat (20) engages with the seat body (35) in a positional regulating manner, or the guide seat (20) is provided integrally with the seat body (35).

6. The electronic expansion valve according to claim 3, characterized in that the locking chamber segment (331) is a frustoconical segment, the radial dimension of the locking chamber segment (331) gradually decreases in the direction toward the valve opening segment (341), the side of the locking segment (1421) facing the valve opening chamber (34) has an annular locking slope for locking engagement with the locking chamber segment (331), the annular locking slope and the locking chamber segment (331) have the same inclination direction, the angle of the angle between the annular locking slope and the axis of the valve core (14) is greater than the angle of the angle between the locking chamber segment (331) and the axis of the valve core (14), and the annular edge connecting the locking chamber segment (331) and the bottom wall of the second valve chamber (33) locks and engages with the annular locking slope.

7. The electronic expansion valve according to claim 3, wherein the locking chamber segment (331) is a cylindrical segment, and the side of the locking segment (1421) facing the valve opening chamber (34) has an annular locking slope for locking and engaging with the locking chamber segment (331), and the annular edge connecting the locking chamber segment (331) and the bottom wall of the second valve chamber (33) locks and engages with the annular locking slope.

8. The electronic expansion valve according to claim 1, wherein the valve core (14) includes a detachably connected seal segment (141) and a closure segment (142), the seal segment (141) engaging sealantly with the inner wall of the valve seat assembly, and the closure segment (142) includes a locking segment (1421) and a flow rate regulating segment (1422) connected to the locking segment (1421), the radial dimension of the locking segment (1421) being greater than the radial dimension of the flow rate regulating segment (1422), and the flow rate regulating segment (1422) engaging positionally with the valve port chamber (34).

9. The electronic expansion valve according to claim 8 is characterized in that the seal segment (141) and the closing segment (142) each have an engagement projection (143) and an engagement groove on their adjacent sides, and the engagement projection (143) engages with the engagement groove in a positional regulating manner.

10. The electronic expansion valve according to claim 1, characterized in that the valve seat assembly or the valve core (14) has an annular seal groove, and the electronic expansion valve further includes an annular seal ring (42), the annular seal ring (42) being positioned within the annular seal groove and sealingly engaging with the valve core (14) and the valve seat assembly, respectively.

11. The second valve chamber (33) has a locking chamber segment (331) on the side facing the valve port chamber (34) for locking and engaging with the locking segment (1421), If the valve seat assembly has the annular seal groove, the inner circumference of the annular seal ring (42) engages with the valve core (14) in a sealed manner, and if the inner diameter of the annular seal ring (42) is D1 and the radial dimension of the closing ring formed by the contact between the valve core (14) and the locking chamber segment (331) is D2, then 1 ≤ D2 / D1 ≤ 1.05 or Alternatively, if the valve core (14) has the annular seal groove, the outer circumference of the annular seal ring (42) engages with the valve seat assembly in a sealed manner, and if the outer diameter of the annular seal ring (42) is D1 and the radial dimension of the closing ring formed by the contact between the valve core (14) and the locking chamber segment (331) is D2, then 1 ≤ D2 / D1 ≤ 1.05, characterized in that the electronic expansion valve according to 10.

12. The electronic expansion valve according to claim 2, further comprising a casing (50) and a drive assembly (60), wherein the casing (50) is connected to the valve seat (30), the drive assembly (60) is disposed within the casing (50), and the end of the drive assembly (60) facing the guide seat (20) is engaged in positional regulating engagement with the guide seat (20) and is connected to the valve seat (30), and the valve needle assembly (10) is sequentially inserted into the drive assembly (60), the guide seat (20), and the valve seat (30).

13. The electronic expansion valve according to claim 12, wherein the valve needle assembly (10) further comprises a screw (11), a connecting member (12), and an elastic member (13), one end of the screw (11) being connected to the drive assembly (60), the other end of the screw (11) being connected to the valve core (14) via the connecting member (12), the connecting member (12) being movably positioned within the guide seat (20) and engaging in positional control with the inner wall of the guide seat (20), one end of the elastic member (13) being in contact with the valve core (14), and the other end of the elastic member (13) being in contact with the screw (11) and / or the connecting member (12).

14. An assembly method applicable to the valve seat assembly of the electronic expansion valve described in claim 2, A step of preparing a plurality of valve seats (30), wherein the radial dimensions of the plurality of closing rings formed by the contact between the locking segment (1421) and the bottom walls of the plurality of second valve chambers (33) are the same, and the radial dimensions of the plurality of valve opening chambers (34) are different, An assembly method characterized by including the step of selecting one suitable valve seat (30) from among them according to the demand and connecting it to the guide seat (20).

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