Electronic expansion valve

Abstract

Provided in the embodiments of the present disclosure is an electronic expansion valve, comprising a valve body (100), a guide assembly, a valve assembly and a sealing assembly, wherein the valve body (100) is provided with a valve cavity (110); the valve cavity (110) is provided with a valve port (111); the guide assembly is arranged in the valve cavity (110), and the guide assembly comprises a guide sleeve (210) and a guide column (220), the guide sleeve (210) being arranged in the valve cavity (110) and being provided with a guide sleeve cavity (211), a fitting step being formed on the inner side wall of the guide sleeve (210), at least part of the guide column (220) being located in the guide sleeve cavity (211), and a sealing groove (230) being formed between the fitting step and the end face of the end of the guide column (220) facing the valve port (111); the sealing assembly is accommodated in the sealing groove (230); a gap is provided between the sealing assembly and at least one of the side wall of the sealing groove (230) close to the valve port (111) and the side wall of the sealing groove (230) away from the valve port (111); an assembly step (2211) is provided on the periphery of the guide column (220); an assembly groove (212) is provided on the cavity wall of the end of the guide sleeve cavity (211) away from the valve port (111); the assembly step (2211) is accommodated in the assembly groove (212), and the side wall of the assembly step facing the valve port (111) abuts against the side wall of the assembly groove (212) facing away from the valve port (111); the guide column (220) is provided with a guide column cavity (223); and part of the valve assembly is arranged in the guide column cavity (223), two ends of the valve assembly extend from the guide assembly, and the valve assembly is configured to open and close the valve port (111).

Description

Electronic expansion valve

[0001] Cross-reference to related applications

[0002] The present disclosure claims priority to Chinese application No. 2024113723479, filed on September 27, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of valves, in particular to an electronic expansion valve. BACKGROUND

[0004] The electronic expansion valve is used as a throttling element to regulate the on-off and flow rate of fluid. The guide assembly of the electronic expansion valve can include a guide sleeve and a guide column, both of which are arranged in the valve cavity, and a sealing groove is formed between the guide sleeve and the guide column for accommodating a sealing assembly. A valve assembly is arranged in the guide sleeve and the guide column and sealingly cooperates with the sealing assembly. However, the sealing assembly expands after being heated and presses the sealing groove and the valve assembly, which can cause the valve assembly to be locked by the sealing assembly, and the valve assembly is difficult to move relative to the sealing assembly, resulting in difficulty in opening and closing the electronic expansion valve. SUMMARY

[0005] The technical problem to be solved by the present disclosure is how to provide an electronic expansion valve capable of avoiding the locking of the valve assembly by the sealing assembly after expansion.

[0006] To solve the above-mentioned problems, the present disclosure provides an electronic expansion valve, which comprises a valve body, a guide assembly, a valve assembly and a sealing assembly. The valve body is provided with a valve cavity, and the valve cavity is provided with a valve port. The guide assembly is arranged in the valve cavity, and the guide assembly comprises a guide sleeve and a guide column. The guide sleeve is arranged in the valve cavity and is provided with a guide sleeve cavity. A cooperation step is formed on the inner side wall of the guide sleeve. The guide column is at least partially located in the guide sleeve cavity, and the end face of the guide column at the end towards the valve port and the cooperation step form a sealing groove. The sealing assembly is accommodated in the sealing groove. There is a gap between at least one of the side wall close to the valve port and the side wall away from the valve port of the sealing groove and the sealing assembly. The outer periphery of the guide column is provided with a fitting step, and the cavity wall of the guide sleeve cavity away from the valve port is provided with a fitting groove. The fitting step is accommodated in the fitting groove, and the side wall of the fitting step towards the valve port and the side wall of the fitting groove away from the valve port abut. The guide column is provided with a guide column cavity. The valve assembly is partially arranged in the guide column cavity, and both ends of the valve assembly respectively protrude out of the guide assembly. The valve assembly is used to open and close the valve port.

[0007] In one embodiment of the present disclosure, the guide column has a first guide section and a second guide section distributed along an axial direction, the first guide section is arranged in the guide sleeve cavity, and the second guide section extends out of the guide sleeve cavity away from the valve port, and an end face of the first guide section close to one end of the valve port and a cavity wall of the guide sleeve cavity form the sealing groove; and the assembly step is located at a connection between the first guide section and the second guide section.

[0008] In one embodiment of the present disclosure, along the axial direction, a length of the first guide section is greater than a length of the second guide section.

[0009] In one embodiment of the present disclosure, the assembly step and the assembly groove are welded.

[0010] In one embodiment of the present disclosure, a welding position of the assembly step and the assembly groove is located between an outer peripheral surface of the assembly step away from the valve port and an inner peripheral groove wall of the assembly groove away from the valve port.

[0011] In one embodiment of the present disclosure, a part of the guide column and an inner wall of the guide sleeve cavity are in interference fit; and a gap fit is formed between an outer peripheral surface of the assembly step and an inner peripheral groove wall of the assembly groove.

[0012] In one embodiment of the present disclosure, a side surface of the assembly step away from the valve port is provided with a groove.

[0013] In one embodiment of the present disclosure, the assembly step is provided with one groove along a circumferential direction, and the groove is in a circular ring type.

[0014] In one embodiment of the present disclosure, the assembly step is provided with at least two grooves along a circumferential direction, the grooves are in a circular ring type, and the at least two grooves are distributed along a radial direction.

[0015] In one embodiment of the present disclosure, the assembly step is provided with at least two grooves along a circumferential direction, the grooves are in a circular arc type, and the at least two grooves are arranged along a same circular path.

[0016] In one embodiment of the present disclosure, along the radial direction, a ratio of a groove width of the groove in a width of the assembly step is 1 / 4-3 / 4.

[0017] In one embodiment of the present disclosure, along the radial direction, a distance between an outer edge of the groove and an outer edge of the assembly step in the width of the assembly step is greater than or equal to 1 / 4.

[0018] In one embodiment of the present disclosure, along the axial direction, a ratio of a groove depth of the groove in a thickness of the assembly step is 1 / 3-1 / 2.

[0019] In one embodiment of the present disclosure, the cavity wall of the guide sleeve cavity is provided with a third chamfer structure adjacent to the assembly groove near one end of the valve port.

[0020] In one embodiment of the present disclosure, the part of the cavity wall of the guide sleeve cavity without the assembly groove and the third chamfer structure has a first area and a second area, which are distributed along the axial direction, and the first area is located between the third chamfer structure and the second area; wherein the first area of the guide sleeve cavity is in clearance fit with the guide column, and the second area of the guide sleeve cavity is in interference fit with the guide column.

[0021] In one embodiment of the present disclosure, the valve assembly comprises a valve head assembly and a nut assembly; the nut assembly is arranged on the part of the guide column protruding out of the guide sleeve cavity and is in guiding fit with the guide column; the valve head assembly is partially arranged in the guide column cavity, one end of which is in screwing fit with the nut assembly so that the valve head assembly can move axially when it rotates, and the other end of which is used to open and close the valve port.

[0022] In one embodiment of the present disclosure, the sealing assembly comprises a sealing ring and an O-ring, and the sealing ring is located between the inner periphery of the O-ring and the valve assembly.

[0023] The beneficial effects of the present disclosure mainly include:

[0024] The electronic expansion valve provided by the present disclosure comprises a valve body, a guide assembly, a valve assembly and a sealing assembly; the valve body is provided with a valve cavity, and the valve cavity is provided with a valve port; the guide assembly comprises a guide sleeve and a guide column; the guide sleeve is arranged in the valve cavity and is provided with a guide sleeve cavity; a cooperation step is formed on the inner side wall of the guide sleeve; the guide column is at least partially located in the guide sleeve cavity; a sealing groove is formed between the end face of the end of the guide column facing the valve port and the cooperation step; the sealing assembly is accommodated in the sealing groove; at least one of the side wall close to the valve port and the side wall away from the valve port of the sealing groove has a gap with the sealing assembly; the outer periphery of the guide column is provided with an assembly step; the cavity wall of the end of the guide sleeve cavity away from the valve port is provided with an assembly groove; the assembly step is accommodated in the assembly groove; the side wall of the assembly step facing the valve port and the side wall of the assembly groove away from the valve port abut; the guide column is provided with a guide column cavity; the valve assembly is partially arranged in the guide column cavity, and the two ends of the valve assembly respectively extend out of the guide assembly; the valve assembly is used for opening and closing the valve port. Through the above design, the cooperation of the assembly step and the assembly groove can realize the limiting effect of the guide column relative to the guide sleeve in the axial direction, so as to limit the part of the guide column arranged in the guide sleeve cavity. Accordingly, the present disclosure can ensure the size of the sealing groove in the axial direction, so that at least one of the side wall close to the valve port and the side wall away from the valve port of the sealing groove has a gap with the sealing assembly, so that the sealing assembly will not extrude the sealing groove and the valve assembly after thermal expansion, preventing the valve assembly from being locked by the sealing assembly, avoiding the problem that the valve assembly is difficult to move relative to the sealing assembly, and ensuring the normal realization of the opening and closing valve function of the electronic expansion valve. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 is a cross-sectional schematic view of an electronic expansion valve according to an exemplary embodiment;

[0026] Fig. 2 is an enlarged schematic view of part A in Fig. 1;

[0027] Fig. 3 is an enlarged schematic view of part B in Fig. 2;

[0028] Fig. 4 is an enlarged schematic view of part C in Fig. 2;

[0029] Fig. 5 is an enlarged schematic view of part D in Fig. 4.

[0030] Wherein, the reference signs are explained as follows: 100. valve body; 110. valve cavity; 111. valve port; 210. guide sleeve; 211. guide sleeve cavity; 212. assembly groove; 213. third chamfer structure; 214. first region; 215. second region; 220. guide post; 221. first guide section; 2211. assembly step; 2212. groove; 222. second guide section; 223. guide post cavity; 230. sealing groove; 310. valve needle; 311. balance channel; 320. shaft core screw; 330. elastic member; 400. nut assembly; 510. sealing ring; 511. third region; 512. fourth region; 513. first chamfer structure; 514. second chamfer structure; 520. O-ring; 600. driving mechanism; d. cross-sectional diameter; h1. groove depth; h2. thickness; w1. cross-sectional width; w2. groove width; w3. distance; w4. width. DETAILED DESCRIPTION

[0031] Example embodiments now will be described more fully hereinafter with reference to the accompanying drawings; however, these embodiments should not be construed as limiting the present disclosure, but merely as illustrating

[0032] Referring to FIG. 1, a cross-sectional schematic view of an electronic expansion valve according to the present disclosure is shown. In the example embodiment, the electronic expansion valve according to the present disclosure is described by way of example as applied to a high-pressure refrigerant system or a super-high-pressure refrigerant system. It will be readily understood by those skilled in the art that various modifications, additions, substitutions, deletions, or other changes can be made to the specific embodiments described below without departing from the principles of the electronic expansion valve according to the present disclosure.

[0033] As shown in FIG. 1, in an embodiment of the present disclosure, the electronic expansion valve according to the present disclosure includes a valve body 100, a guide assembly, a valve assembly, and a sealing assembly. For a better understanding, refer to FIGS. 2-5, which show enlarged views of portions A, B, C, and D of FIG. 1, respectively.

[0034] As shown in FIGS. 1-3, in an embodiment of the present disclosure, the valve body 100 is provided with a valve cavity 110, and the valve cavity 110 is provided with a valve port 111. A guide assembly is arranged in the valve cavity 110, and the guide assembly includes a guide sleeve 210 and a guide column 220. The guide sleeve 210 is arranged in the valve cavity 110, and the guide sleeve 210 is provided with a sleeve cavity 211. A matching step is formed on the inner side wall of the guide sleeve 210. The guide column 220 is at least partially located in the sleeve cavity 211. A sealing groove 230 is formed between the end face of the guide column 220 at the end close to the valve port 111 and the matching step. A sealing assembly is accommodated in the sealing groove 230. There is a gap between at least one of the side wall close to the valve port 111 and the side wall away from the valve port 111 of the sealing groove 230 and the sealing assembly. On this basis, the outer periphery of the guide column 220 is provided with a fitting step 2211. The cavity wall of the sleeve cavity 211 at the end away from the valve port 111 is provided with a fitting groove 212. The fitting step 2211 is accommodated in the fitting groove 212. The side wall of the fitting step 2211 close to the valve port 111 and the side wall of the fitting groove 212 away from the valve port 111 abut. The guide column 220 is provided with a guide column cavity 223. A valve assembly is arranged in the guide column cavity 223, and both ends of the valve assembly respectively extend out of the guide assembly. The valve assembly is used to open and close the valve port 111. Through the above design, the present disclosure can realize the limiting effect of the guide column 220 relative to the guide sleeve 210 along the axial direction by the cooperation of the fitting step 2211 and the fitting groove 212, so as to limit the part of the guide column 220 arranged in the sleeve cavity 211. Accordingly, the present disclosure can ensure the size of the sealing groove 230 in the axial direction, so that there is a gap between at least one of the side wall close to the valve port 111 and the side wall away from the valve port 111 of the sealing groove 230 and the sealing assembly (see FIG. 3). Accordingly, the sealing assembly will not press the sealing groove 230 and the valve assembly after thermal expansion, so as to prevent the valve assembly from being locked by the sealing assembly, avoid the problem that the valve assembly is difficult to move relative to the sealing assembly, and ensure the normal realization of the opening and closing valve function of the electronic expansion valve.

[0035] As shown in FIGS. 1-3, in an embodiment of the present disclosure, the guide column 220 has a first guide section 221 and a second guide section 222 distributed along the axial direction. The first guide section 221 is arranged in the sleeve cavity 211. The second guide section 222 extends out of the sleeve cavity 211 away from the valve port 111, and the second guide section 222 is used to arrange a nut assembly 400. The guide column 220 is provided with a guide column cavity 223. On this basis, the fitting step 2211 can be located at the connection between the first guide section 221 and the second guide section 222. Accordingly, the end face of the first guide section 221 at the end close to the valve port 111 and the cavity wall of the sleeve cavity 211 form the above-mentioned sealing groove 230.

[0036] As shown in FIG. 2, in an embodiment of the present disclosure, the length of the first guide section 221 can be greater than the length of the second guide section in the axial direction. By the above design, when the assembly step 2211 is welded with the assembly groove 212, the present disclosure can prolong the distance between the sealing groove (i.e. the sealing position of the guide assembly and the valve head assembly) and the welding position (i.e. the welding position of the guide sleeve 210 and the guide column 220), thereby reducing the thermal influence of welding on the sealing assembly.

[0037] As shown in FIG. 2 and FIG. 4, in an embodiment of the present disclosure, the wall thickness of the first guide section 221 can be greater than the wall thickness of the second guide section 222.

[0038] In an embodiment of the present disclosure, the assembly step 2211 can be welded with the assembly groove 212.

[0039] In an embodiment of the present disclosure, the side surface of the assembly step 2211 away from the valve port 111 can be provided with a groove 2212. By the above design, when the assembly step 2211 is welded with the assembly groove 212, the present disclosure can block the heat conduction of welding, avoid the deformation of the guide surface of the guide column 220 for cooperating with the valve assembly (such as the nut assembly 400 of the valve assembly), and ensure the guiding effect of the guide column 220 on the valve assembly.

[0040] Specifically, the welding connection mode can realize the connection of the guide column 220 and the guide sleeve 210, and can realize the sealing of the connection position through the annular welding path, thereby further enhancing the sealing effect between the guide column 220 and the guide sleeve 210. On this basis, the welding connection of the guide sleeve 210 and the guide column 220 can cause the poor coaxiality of the guide column 220, and the welding process can heat the guide column 220, so that the guide column 220 is deformed under the influence of heat, the outer side wall of the guide column 220 is deformed, and the guiding effect of the guide column 220 on the nut assembly 400 is affected. Further, due to the press-fitting between the nut assembly 400 and the outer side wall of the guide column 220 (such as the second guide section 222), the deformation of the guide column 220 under the influence of heat will cause the press-fitting difficulty of the nut assembly 400, and the positioning inaccuracy of the nut assembly 400, and the position deviation of the nut assembly 400 after installation, thereby causing the uneven movement of the mandrel screw, and the jamming. In addition, when the inner surface of the guide column 220 (i.e. the cavity wall of the guide column cavity 223) is deformed greatly under the influence of heat, the elastic member 330 inside the guide column cavity 223 will also move unevenly and jam. Therefore, by providing the groove 2212 on the guide column 220, the present disclosure can block the heat conduction, reduce the influence of welding on the coaxiality of the guide column 220, and provide a deformation space for the deformation of the outer side of the groove 2212, thereby avoiding the deformation of the outer side of the groove 2212 from being conducted to the inside of the groove 2212 and affecting the coaxiality of the guide column 220.

[0041] As shown in FIG. 4, in an embodiment of the present disclosure, the valve assembly can include a valve head assembly and a nut assembly 400. Specifically, the nut assembly 400 is arranged on the portion of the guide post 220 that extends out of the guide sleeve cavity 211 away from the valve port 111, and the nut assembly 400 is guided and matched with the guide post 220. The valve head assembly is arranged in the guide post cavity 223, and the two ends of the valve head assembly can respectively extend out of the guide assembly. One end of the valve head assembly is screwed and matched with the nut assembly 400, so that the valve head assembly can move axially when it rotates. The other end of the valve head assembly is used to open and close the valve port 111. Accordingly, since the valve head assembly is screwed and matched with the nut assembly 400, and since the nut assembly 400 is fixed relative to the valve body 100 and the guide assembly, when the valve head assembly rotates, the valve head assembly can move axially. It should be noted that, unlike the driving mode in the present embodiment in which the nut assembly 400 is fixed and the shaft core screw 320 drives the valve head assembly to move, when the valve assembly includes the valve head assembly and the nut assembly 400, the electronic expansion valve proposed in the present disclosure can also use other driving modes, for example, the shaft core screw 320 can rotate circumferentially but is relatively fixed axially, and the valve head assembly and the nut assembly 400 can move axially but are relatively fixed circumferentially.

[0042] As shown in FIG. 2, in an embodiment of the present disclosure, the valve head assembly includes a valve needle 310 and a shaft core screw 320. The first end (for example, the end facing the valve port 111) of the valve needle 310 extends out of the guide assembly, one end of the shaft core screw 320 is connected to the second end (for example, the end away from the valve port 111) of the valve needle 310, the shaft core screw 320 is driven by the driving mechanism 600 to rotate around the axial direction, and the shaft core screw 320 is screwed and matched with the nut assembly 400. Accordingly, since the shaft core screw 320 is screwed and matched with the nut assembly 400, and since the nut assembly 400 is fixed relative to the valve body 100 and the guide assembly, when the shaft core screw 320 rotates, the shaft core screw 320 can move axially, thereby driving the valve needle 310 to move axially, and thus the first end of the valve needle 310 opens or closes the valve port 111.

[0043] As shown in FIG. 5, in an embodiment of the present disclosure, the welding position of the assembly step 2211 and the assembly groove 212 can be located between the outer peripheral surface of the assembly step 2211 away from the valve port and the inner peripheral groove wall of the assembly groove 212 away from the valve port. Wherein, the welding mode of the assembly step 2211 and the assembly groove 212 can be laser welding.

[0044] As shown in FIG. 5, in an embodiment of the present disclosure, a portion of the guide column 220 and the inner wall of the guide sleeve cavity 211 can be in interference fit. On this basis, the outer circumferential surface of the assembly step 2211 and the inner circumferential groove wall of the assembly groove 212 can be in clearance fit. Through the above design, the present disclosure uses interference fit between a portion of the guide column 220 and the inner wall of the guide sleeve cavity 211, which can strengthen the assembly effect of the guide column 220 and the guide sleeve cavity 211. On this basis, the present disclosure uses clearance fit between the outer circumferential surface of the assembly step 2211 and the inner circumferential groove wall of the assembly groove 212, which can avoid the coaxiality problem caused by interference fit at the above two fit positions, thereby avoiding installation difficulties.

[0045] It should be noted that the above clearance fit is the fit state after the guide sleeve 210 and the guide column 220 are assembled (i.e., the guide column 220 is partially inserted into the guide sleeve cavity 211 and the assembly step 2211 is accommodated in the assembly groove 212) and before welding. It should be understood that when the outer circumferential surface of the assembly step 2211 and the inner circumferential groove wall of the assembly groove 212 are welded, the structure type of the above fit position observed from the cross section of the electronic expansion valve may not fully comply with the above description, but does not limit the application of the present disclosure in related embodiments.

[0046] As shown in FIG. 5, in an embodiment of the present disclosure, the assembly step 2211 can be provided with a groove 2212 in the circumferential direction, and the groove 2212 can be in the form of a circular ring. In some embodiments, the assembly step 2211 can also be provided with at least two grooves 2212 in the circumferential direction, and the grooves 2212 can also be in the form of a circular ring, and the at least two grooves 2212 can be distributed in the radial direction, for example, at least two circular ring type grooves 2212 with different diameters are spaced apart. Alternatively, the assembly step 2211 can also be provided with at least two grooves 2212 in the circumferential direction, and the grooves 2212 can be in the form of a circular arc, and the at least two grooves 2212 can be arranged in the same circular path.

[0047] As shown in FIG. 5, in an embodiment of the present disclosure, along the radial direction, the ratio of the groove width w2 of the groove 2212 in the width w4 of the assembly step 2211 can be 1 / 4-3 / 4, for example, 1 / 4, 1 / 2, 5 / 8, 3 / 4, etc. Wherein the width w4 of the assembly step 2211 can be understood as the radial distance between the outer periphery of the assembly step 2211 and the outer periphery of the second guide section 222. Through the above design, the present disclosure can avoid that the groove width w2 of the groove 2212 is too small to make the heat resistance or deformation transmission blocking ability not obvious enough, at the same time, the present disclosure can avoid that the groove width w2 of the groove 2212 is too large to affect the structural strength of the assembly step 2211, and ensure the assembly strength of the guide sleeve 210 and the guide column 220. In some embodiments, the ratio of the groove width w2 of the groove 2212 in the width w4 of the assembly step 2211 can also be less than 1 / 4, or can be greater than 3 / 4, for example, 1 / 5, 4 / 5, etc., which is not limited by the present embodiment.

[0048] As shown in FIG. 5, in an embodiment of the present disclosure, along the radial direction, the distance w3 between the outer edge of the groove 2212 and the outer edge of the assembly step 2211 can be greater than or equal to 1 / 4 of the width of the assembly step 2211, for example, 1 / 4, 1 / 3, 1 / 2, 5 / 8, etc. Through the above design, the present disclosure can avoid that the ratio of the above distance w3 in the width of the assembly step 2211 is too small to make the groove 2212 too close to the outer edge of the assembly step 2211, and ensure the structural strength of the assembly step 2211, at the same time, the present disclosure can avoid that the ratio of the above distance w3 in the width of the assembly step 2211 is too large to make the space for arranging the groove 2212 on the assembly step 2211 smaller. In some embodiments, the ratio of the distance w3 between the outer edge of the groove 2212 and the outer edge of the assembly step 2211 in the width of the assembly step 2211 can also be less than 1 / 4, for example, 1 / 5 mm, etc., which is not limited by the present embodiment.

[0049] As shown in FIG. 5, based on the design that the assembly step 2211 is provided with the groove 2212, in an embodiment of the present disclosure, along the axial direction, the ratio of the groove depth h1 of the groove 2212 in the thickness h2 of the assembly step 2211 can be 1 / 3-1 / 2, for example, 1 / 3, 3 / 8, 2 / 5, 1 / 2, etc. Through the above design, the present disclosure can avoid that the groove depth h1 of the groove 2212 is too small to make the heat resistance or deformation transmission blocking ability not obvious enough, at the same time, the present disclosure can avoid that the groove depth h1 of the groove 2212 is too large to affect the structural strength of the assembly step 2211, and ensure the assembly strength of the guide sleeve 210 and the guide column 220. In some embodiments, the ratio of the groove depth h1 of the groove 2212 in the thickness h2 of the assembly step 2211 can also be less than 1 / 3, or can be greater than 1 / 2, for example, 3 / 10, 11 / 20, etc., which is not limited by the present embodiment.

[0050] As shown in FIG. 5, based on the matching design of the assembly step 2211 and the assembly groove 212, in an embodiment of the present disclosure, the cavity wall of the guide sleeve cavity 211 can be provided with a third chamfer structure 213 adjacent to the assembly groove 212 near one end of the valve port 111. For example, the third chamfer structure 213 can be an inverted bevel structure as shown, or a rounded chamfer structure. Through the above design, in the assembly process of the guide column 220 and the guide sleeve 210 (for example, in the process of inserting the guide column 220 into the guide sleeve cavity 211), the present disclosure can guide the guide column 220 by using the third chamfer structure 213, further reducing the assembly difficulty.

[0051] As shown in FIG. 5, based on the design that the cavity wall of the guide sleeve cavity 211 is provided with the third chamfer structure 213, in an embodiment of the present disclosure, the part of the cavity wall of the guide sleeve cavity 211 which is not provided with the assembly groove 212 and the third chamfer structure 213 can have a first area 214 and a second area 215, and the first area 214 and the second area 215 are distributed along the axial direction, and the first area 214 is located between the third chamfer structure 213 and the second area 215. On this basis, the first area 214 of the guide sleeve cavity 211 can be clearance fit with the guide column 220, and the second area 215 of the guide sleeve cavity 211 can be interference fit with the guide column 220. Through the above design, considering the installation mode of the sealing ring 510 and the O-ring 520, the guide sleeve 210 can be assembled with the valve body 100 first (for example, by using furnace welding), then the sealing ring 510 and the O-ring 520 are put into the guide sleeve 210, and then the guide column 220 is assembled into the guide sleeve 210, and the guide column 220 and the guide sleeve 210 are assembled to form a sealing groove 230 together, and the guide column 220 and the guide sleeve 210 are clearance fit at the end away from the valve port 111 (i.e. the upper end shown in the figure). Accordingly, although the guide sleeve 210 is provided with the third chamfer structure 213, the guide column 220 can still be pressed and installed with deflection or not in place, and the present disclosure uses the above clearance fit design to provide self-guiding effect for the installation of the guide column 220 in the guide sleeve 210, so as to achieve good pressing and installation and the design purpose of not needing a guide pressing tool. Furthermore, since the guide column 220 will be subjected to an upward pressure difference (in the case that the valve needle 310 is provided with a balance channel as shown, the fluid pressure at the lower end of the guide column 220 will be greater than that at the upper end, so the guide column 220 will actually be subjected to an upward pressure difference, for example, a pressure difference of 10 MPa, which is opposite to the valve port 111), the present disclosure uses interference fit between the guide column 220 and the guide sleeve 210 at the end close to the valve port 111 (i.e. the lower end shown in the figure), which can overcome the influence of the above pressure difference on the assembly strength of the guide column 220 and the guide sleeve 210, further ensure the assembly strength between them, and at the same time ensure the coaxiality between the guide column 220 and the guide sleeve 210.

[0052] As shown in FIG. 2, in an embodiment of the present disclosure, on this basis, the sealing assembly can include a sealing ring 510 and an O-ring 520, the sealing ring 510 is located between the inner periphery of the O-ring 520 and the valve needle 310, and the so-called "O" refers to the cross section of the O-ring 520 being circular (i.e., the profile of the cross section is "O" shaped). Through the above design, the present disclosure adopts the sealing ring 510 and the O-ring 520 to constitute the sealing assembly to realize the sealing function between the guide assembly and the valve needle 310, which can avoid the deformation of the O-ring 520 caused by extrusion in a high-pressure environment by the design of the sealing ring 510, and ensure the stability and reliability of the sealing function of the electronic expansion valve.

[0053] In an embodiment of the present disclosure, at least part of the inner periphery of the sealing ring 510 can be a tapered inner annular surface, the inner diameter of the tapered inner annular surface away from one end of the valve port 111 is greater than the inner diameter of the tapered inner annular surface close to one end of the valve port 111. In other words, at least the region close to one end of the valve port 111 and adjacent to the tapered inner annular surface of the inner periphery of the sealing ring 510 abuts the outer periphery of the valve needle 310.

[0054] It should be noted that the description of the shape of the sealing ring 510 in the present specification is based on the structure of the sealing ring 510 when it is not assembled, and it should be understood that when the sealing ring 510 is assembled, or after the electronic expansion valve is used for a period of time, the structure of the sealing ring 510 observed from the cross section of the electronic expansion valve or the structure of the sealing ring 510 disassembled may not completely match the above description, but it does not limit the application of the present disclosure in related embodiments.

[0055] In an embodiment of the present disclosure, the material of the sealing ring 510 can be PTFE (Polytetrafluoro-Ethylene, chemical formula: (C2F4)n).

[0056] It should be noted that the electronic expansion valve shown in the drawings and described in the present specification is only a few examples of many electronic expansion valves that can employ the principles of the present disclosure. It should be clearly understood that the principles of the present disclosure are by no means limited to any details of the electronic expansion valve or any components of the electronic expansion valve shown in the drawings or described in the present specification.

[0057] In summary, the electronic expansion valve provided by the present disclosure comprises a valve body 100, a guide assembly, a valve assembly and a sealing assembly; the valve body 100 is provided with a valve cavity 110, and the valve cavity 110 is provided with a valve port 111; the guide assembly comprises a guide sleeve 210 and a guide column 220; the guide sleeve 210 is arranged in the valve cavity 110 and is provided with a guide sleeve cavity 211, a cooperation step is formed on the inner side wall of the guide sleeve 210, the guide column 220 is at least partially located in the guide sleeve cavity 211, and a sealing groove 230 is formed between the end face of the end of the guide column 220 facing the valve port 111 and the cooperation step; the sealing assembly is accommodated in the sealing groove 230, and there is a gap between at least one of the side wall close to the valve port 111 and the side wall away from the valve port 111 of the sealing groove 230 and the sealing assembly; the outer periphery of the guide column 220 is provided with an assembly step, the cavity wall of the guide sleeve cavity 211 away from the valve port 111 is provided with an assembly groove 212, the assembly step is accommodated in the assembly groove 212, and the side wall of the assembly step facing the valve port 111 is in abutment with the side wall of the assembly groove 212 away from the valve port 111, and the guide column 220 is provided with a guide column cavity 223; the valve assembly is partially arranged in the guide column cavity 223, and the two ends thereof respectively extend out of the guide assembly, and the valve assembly is used for opening and closing the valve port 111. Through the above design, the cooperation between the assembly step 2211 and the assembly groove 212 can realize the limiting effect of the guide column 220 relative to the guide sleeve 210 along the axial direction, so as to limit the part of the guide column 220 arranged in the guide sleeve cavity 211. Accordingly, the present disclosure can ensure the size of the sealing groove 230 in the axial direction, so that there is a gap between at least one of the side wall close to the valve port 111 and the side wall away from the valve port 111 of the sealing groove 230 and the sealing assembly, so that the sealing assembly will not press the sealing groove 230 and the valve assembly after thermal expansion, thereby preventing the valve assembly from being locked by the sealing assembly and avoiding the problem that the valve assembly is difficult to move relative to the sealing assembly, and ensuring the normal realization of the opening and closing valve function of the electronic expansion valve.

[0058] Although the present disclosure has been described with reference to several exemplary embodiments, it is understood that the terms used are illustrative and not restrictive terms. Since the present disclosure can be embodied in various forms without departing from the spirit or essential characteristics thereof, it should be understood that the above-described embodiments are not limited to any of the aforementioned details, but are to be interpreted broadly within the spirit and scope of the appended claims, thus falling within the scope of the claims or their equivalents.

Claims

1. An electronic expansion valve, characterized in that: comprising a valve body (100), a guide assembly, a valve assembly and a sealing assembly; the valve body (100) is provided with a valve cavity (110) provided with a valve port (111); the guide assembly is arranged in the valve cavity (110), and the guide assembly comprises a guide sleeve (210) and a guide column (220); the guide sleeve (210) is arranged in the valve cavity (110) and is provided with a guide sleeve cavity (211); a matching step is formed on the inner side wall of the guide sleeve (210); the guide column (220) is at least partially located in the guide sleeve cavity (211), and a sealing groove (230) is formed between the end face of the guide column (220) towards the valve port (111) and the matching step; the sealing assembly is accommodated in the sealing groove (230), and there is a gap between at least one of the side wall close to the valve port (111) and the side wall away from the valve port (111) of the sealing groove (230) and the sealing assembly; the outer periphery of the guide column (220) is provided with a fitting step (2211), the cavity wall of the guide sleeve cavity (211) away from the valve port (111) is provided with a fitting groove (212), the fitting step (2211) is accommodated in the fitting groove (212), and the side wall of the fitting step towards the valve port (111) and the side wall of the fitting groove (212) away from the valve port (111) are in contact; the guide column (220) is provided with a guide column cavity (223); the valve assembly is partially arranged in the guide column cavity (223) and extends out of the guide assembly at both ends; the valve assembly is used to open and close the valve port (111). The guide column (220) has a first guide section (221) and a second guide section (222) distributed along the axial direction; the first guide section (221) is arranged in the guide sleeve cavity (211), and the second guide section (222) extends out of the guide sleeve cavity (211) away from the valve port (111); the end face of the first guide section (221) close to the valve port (111) and the cavity wall of the guide sleeve cavity (211) form the sealing groove (230); the fitting step (2211) is located at the connection between the first guide section (221) and the second guide section (222). In the axial direction, the length of the first guide section (221) is greater than the length of the second guide section (222). The fitting step (2211) and the fitting groove (212) are welded. The welding position of the fitting step (2211) and the fitting groove (212) is between the end of the outer peripheral surface of the fitting step (2211) away from the valve port (111) and the end of the inner peripheral groove wall of the fitting groove (212) away from the valve port (111). A part of the guide column (220) and the inner wall of the guide sleeve cavity (211) are in interference fit; wherein the outer peripheral surface of the fitting step (2211) and the inner peripheral groove wall of the fitting groove (212) are in clearance fit.

2. The electronic expansion valve according to claim 1, characterized in that ​ 3. The electronic expansion valve according to claim 2, characterized in that ​ 4. The electronic expansion valve according to claim 1, wherein ​ 5. The electronic expansion valve according to claim 4, wherein ​ 6. The electronic expansion valve according to claim 1, wherein ​ 7. The electronic expansion valve according to claim 1, wherein The assembly step (2211) is provided with a groove (2212) on the side surface away from the valve port (111).

8. The electronic expansion valve according to claim 7, characterized in that The assembly step (2211) is provided with one groove (2212) in the circumferential direction, and the groove (2212) is in the form of a circular ring.

9. The electronic expansion valve according to claim 7, wherein The assembly step (2211) is provided with at least two grooves (2212) in the circumferential direction, and the grooves (2212) are in the form of a circular ring, and the at least two grooves (2212) are distributed in the radial direction.

10. The electronic expansion valve according to claim 7, wherein The assembly step (2211) is provided with at least two grooves (2212) in the circumferential direction, and the grooves (2212) are in the form of a circular arc, and the at least two grooves (2212) are arranged in the same circular path.

11. The electronic expansion valve according to claim 7, wherein In the radial direction, the ratio of the groove width (w2) of the groove (2212) in the width of the assembly step (2211) is 1 / 4-3 / 4.

12. The electronic expansion valve according to claim 7, wherein In the radial direction, the distance (w3) between the outer edge of the groove (2212) and the outer edge of the assembly step (2211) is greater than or equal to 1 / 4 of the width of the assembly step (2211).

13. The electronic expansion valve according to claim 7, wherein In the axial direction, the ratio of the groove depth (h1) of the groove (2212) in the thickness (h2) of the assembly step (2211) is 1 / 3-1 / 2.

14. The electronic expansion valve of claim 1, wherein, The cavity wall of the guide sleeve cavity (211) is provided with a third chamfer structure (213) adjacent to the assembly groove (212) near the valve port (111).

15. The electronic expansion valve according to claim 14, wherein The part of the cavity wall of the guide sleeve cavity (211) without the assembly groove (212) and the third chamfer structure (213) has a first area (214) and a second area (215), the first area (214) and the second area (215) are distributed in the axial direction, and the first area (214) is located between the third chamfer structure (213) and the second area (215); wherein the first area (214) of the guide sleeve cavity (211) is in clearance fit with the guide column (220), and the second area (215) of the guide sleeve cavity (211) is in interference fit with the guide column (220).

16. The electronic expansion valve according to any one of claims 1 to 15, characterized in that The valve assembly includes a valve head assembly and a nut assembly (400); the nut assembly (400) is arranged on the part of the guide column (220) protruding out of the guide sleeve cavity (211), and is in guiding fit with the guide column (220); the valve head assembly is partially arranged in the guide column cavity (223), one end of the valve head assembly is in screw fit with the nut assembly (400), so that the valve head assembly can move in the axial direction when rotating, and the other end of the valve head assembly is used for opening and closing the valve port (111).

17. The electronic expansion valve according to any one of claims 1 to 15, characterized in that The sealing assembly includes a sealing ring (510) and an O-ring (520), and the sealing ring (510) is located between the inner periphery of the O-ring (520) and the valve assembly.

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