Electronic expansion valve and refrigeration equipment

Abstract

The utility model discloses an electronic expansion valve and a refrigeration device, and relates to the technical field of refrigeration devices, wherein the electronic expansion valve comprises a valve seat, a first valve needle, a second valve needle and a compression sleeve, the valve seat has a first valve port; the first valve needle sleeves the second valve needle, the first valve needle is arranged in the valve seat, the first valve needle has a second valve port; the compression sleeve is fixed by riveting to the first valve needle. The technical solution provided by the utility model realizes the fixation of the large valve needle and the compression sleeve by riveting the large valve needle and the compression sleeve, solves the problem of fixing the compression sleeve and the large valve needle, reduces the cost of components, and improves the market competitiveness of the product.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration equipment, in particular to an electronic expansion valve and refrigeration equipment. Background Art

[0002] In a double-valve needle electronic expansion valve, the small valve needle is required to move axially up and down within a certain distance range in the inner cavity of the large valve needle. Therefore, it is necessary to limit the small valve needle through a compression sleeve inside the large valve needle. In the related art, the compression sleeve and the large valve needle are assembled by compression fit, which has high precision requirements and complex assembly. Utility Model Content

[0003] The main purpose of the utility model is to propose an electronic expansion valve and refrigeration equipment, aiming to solve the problem of fixing the compression sleeve and the large valve needle. The large valve needle and the compression sleeve are riveted together to achieve fixation of the large valve needle and the compression sleeve, thereby reducing the cost of components and improving the market competitiveness of the product.

[0004] To achieve the above-mentioned purpose, the electronic expansion valve proposed by the utility model comprises:

[0005] A valve seat having a first valve port;

[0006] a first valve needle and a second valve needle, wherein the first valve needle sleeves the second valve needle, the first valve needle is disposed in a valve seat, and the first valve needle has a second valve port; and

[0007] A pressing sleeve, wherein the pressing sleeve is riveted to the first valve needle, and a limiting cavity is provided between the pressing sleeve and the first valve needle, and the second valve needle moves axially relative to the first valve needle to change the opening of the second valve port; the second valve needle moves in the limiting cavity and drives the first valve needle by abutting against the pressing sleeve to change the opening of the first valve port.

[0008] In one embodiment, the electronic expansion valve also includes a reset spring and a nut assembly connected to the valve seat, the reset spring is sleeved on the second valve needle, the end of the pressing sleeve is recessed inward to form a sunken step, and a first mounting groove is formed between the outer wall of the second valve needle and the sunken step, one end of the reset spring abuts against the nut assembly, and the other end is arranged in the first mounting groove.

[0009] In one embodiment, the depth of the sunken step is ≥ 1 mm.

[0010] In one embodiment, the gap between the outer wall of the return spring and the sinking step is 0.1 mm-0.2 mm.

[0011] In one embodiment, the gap between the inner wall of the return spring and the outer wall of the second valve needle is 0.5 mm-1 mm.

[0012] In one embodiment, the end of the nut assembly is recessed inward relative to the pressing sleeve to form a second installation groove, and one end of the return spring is disposed in the second installation groove.

[0013] In one embodiment, the end of the first valve needle is recessed inward to form an accommodating cavity, the accommodating cavity is communicated with the limiting cavity, the pressing sleeve is installed in the accommodating cavity, and the end of the first valve needle is provided with a first rivet, and the first rivet is fixed to the pressing sleeve by riveting.

[0014] In one embodiment, the upper surface of the pressing sleeve is higher than the edge of the cavity opening of the accommodating cavity, and the end of the first rivet is higher than the upper surface of the pressing sleeve.

[0015] In one embodiment, the first rivet is 0.3 mm to 1 mm higher than the upper surface of the press sleeve.

[0016] In one embodiment, the first rivet member is an annular structure, and an inner end of the first rivet member is chamfered.

[0017] In one embodiment, an outer side wall of the first rivet member and an outer side wall of the first valve needle form an arc-shaped transition.

[0018] In one embodiment, the diameter of the accommodating cavity is greater than the diameter of the limiting cavity, and the edge portion of the pressing sleeve is located in the limiting cavity.

[0019] In one embodiment, the gap between the outer wall of the pressing sleeve and the inner wall of the accommodating cavity is 0.05 mm-0.15 mm.

[0020] In one embodiment, the electronic expansion valve also includes a valve needle gasket and a sealing ring. The bottom wall of the limiting cavity is provided with a second rivet, and a gasket groove and a sealing groove with reduced inner diameters. The sealing ring is arranged in the sealing groove. The valve needle gasket is installed in the gasket groove and is located above the sealing groove. The second rivet is riveted and fixed to the valve needle gasket.

[0021] In one embodiment, the upper surface of the valve needle gasket is higher than the notch edge of the gasket groove, and the end of the second rivet is higher than the upper surface of the valve needle gasket.

[0022] In one embodiment, the height of the second rivet is 0.3 mm-1 mm.

[0023] In one embodiment, the wall thickness of the second rivet is 0.1 mm-0.3 mm.

[0024] In one embodiment, the second rivet member and the valve needle gasket are connected by flange riveting; or, the second rivet member and the valve needle gasket are connected by dot-punching deformation riveting.

[0025] In one embodiment, a plurality of the second rivet members are provided.

[0026] In one embodiment, the electronic expansion valve also includes a valve needle gasket and a sealing ring. The bottom wall of the limiting cavity is provided with a sealing groove. The sealing ring is arranged in the sealing groove. The valve needle gasket is installed in the limiting cavity and is located above the sealing groove. The end of the side wall of the pressing sleeve abuts against the valve needle gasket.

[0027] In one embodiment, the pressing sleeve is integrally formed by injection molding.

[0028] In one embodiment, the valve needle gasket is integrally formed by injection molding.

[0029] The utility model also provides a refrigeration device, comprising the electronic expansion valve as described above.

[0030] The technical solution of the utility model fixes the pressing sleeve and the first valve needle by riveting, thereby reducing the high precision requirement of the pressing sleeve and the first valve needle and reducing the manufacturing cost; it also avoids the deformation of the sealing ring that may be caused by welding, resulting in internal leakage failure, thereby improving product reliability, reducing component costs, and enhancing product market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0032] Figure 1 A structural schematic diagram of an embodiment of an electronic expansion valve provided by the utility model;

[0033] Figure 2 A structural schematic diagram of another embodiment of the electronic expansion valve provided by the utility model;

[0034] Figure 3 for Figure 2 The enlarged view of point A in the middle;

[0035] Figure 4 It is a structural schematic diagram of a pressing sleeve embodiment;

[0036] Figure 5 It is a structural schematic diagram of an embodiment of the cooperation between the first valve needle and the second valve needle;

[0037] Figure 6 for Figure 5 Enlarged view of point B in the middle;

[0038] Figure 7 It is a structural schematic diagram of another embodiment of the cooperation between the first valve needle and the second valve needle;

[0039] Figure 8 for Figure 7 Enlarged view of point C in the middle;

[0040] Fig. 9 is a schematic structural diagram of an embodiment of a first valve needle;

[0041] Fig.10 for Fig. 9 A schematic diagram of the cross-sectional structure of;

[0042] Fig.11 is a structural schematic diagram of another embodiment of the first valve needle;

[0043] Fig.12 for Fig.11 Schematic diagram of the cross-sectional structure.

[0044] Description of Figure Numbers:

[0045] 100, electronic expansion valve; 101, shell; 102, valve needle gasket; 103, sealing ring; 110, valve seat; 111, inlet; 112, first valve port; 120, first valve needle; 121, second valve port; 122, accommodating chamber; 123, limiting chamber; 124, first rivet; 125, chamfer; 126, arc-shaped transition; 127, sealing groove; 128, second rivet; 129, gasket groove; 140, second valve needle; 141, limiting portion; 150, pressing sleeve; 151, sinking step; 152, first mounting groove; 160, nut assembly; 161, second mounting groove; 170, return spring; 180, rotor assembly; 190, screw rod.

[0046] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0048] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0049] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0050] In the electronic expansion valve with double valve needles, the small valve needle needs to move up and down axially within a certain distance range in the inner cavity of the large valve needle, so it is necessary to limit the small valve needle through a compression sleeve in the large valve needle; in the related technology, the compression sleeve and the large valve needle are assembled by compression fit, which has high precision requirements and complex assembly; in the related technology, the heat is easily transferred to the sealing ring during the welding process, causing the sealing ring to deform due to heat, internal leakage failure, affecting the system energy efficiency, and even system failure. In addition, the large valve needle compression sleeve and the small valve needle are both made of metal. During the up and down movement of the small valve needle, the quality problem of welding will cause mutual friction between the two, resulting in noise and even friction jamming.

[0051] For this purpose, refer to Figure 1 and Figure 2 The utility model provides an electronic expansion valve 100 for adjusting the flow of refrigerant and is applied in refrigeration and air-conditioning systems.

[0052] See also Figures 1 to 12In one embodiment of the utility model, the electronic expansion valve 100 includes a housing 101, a valve seat 110, a first valve needle 120, a second valve needle 140, a compression sleeve 150, a nut assembly 160, a return spring 170, a rotor assembly 180, a screw rod 190, an electromagnetic coil, etc.; the valve seat 110 has a radially arranged valve seat 110 inlet 111 and a first valve port 112 axially connected to the inlet 111, the top of the valve seat 110 is connected to the housing 101, the rotor assembly 180 is arranged in the housing 101, the top of the valve seat 110 is provided with a mounting port, and the nut assembly 160 is embedded in The first valve needle 120 is arranged in the nut assembly 160 and the valve seat 110, and the second valve needle 140 passes through the first valve needle 120. The end of the second valve needle 140 is provided with an inner opening. A guide sleeve is provided on the screw rod 190 and is placed in the inner opening, and is provided in the inner opening through a bearing. The screw rod 190 abuts against the bearing through the guide sleeve to drive the second valve needle 140 to move; the reset spring 170 abuts against the nut assembly 160 and the first valve needle 120. Under the action of the reset spring 170, the first valve needle 120 has a tendency to move away from the nut assembly 160.

[0053] An axial hole for the second valve needle 140 to pass through is provided in the first valve needle 120, and a sealing groove 127 is provided at the end of the axial hole. A sealing ring 103 is provided in the sealing groove 127. The second valve needle 140 is sealed with the first valve needle 120 via the sealing ring 103. A valve needle gasket 102 is provided above the sealing ring 103. The bottom of the second valve needle 140 can contact the valve needle gasket 102, and the valve needle gasket 102 disperses the force on the second valve needle 140.

[0054] The pressing sleeve 150 is arranged at the end of the first valve needle 120, and a limited position cavity 123 is formed between the pressing sleeve 150 and the first valve needle 120. In one embodiment, the axis of the second valve needle 140 radially extends to a limited position portion 141, and the limited position portion 141 cooperates with the pressing sleeve 150 to drive the first valve needle 120 to move; in another embodiment, the second valve needle 140 drives the first valve needle 120 to move by interference fit with the axial hole of the pressing sleeve 150. The first valve needle 120 is provided with a valve needle inlet 111 and a second valve port 121. In the closed state, the second valve needle 140 closes the valve needle inlet 111. 11 and the second valve port 121. In the open state, the second valve needle 140 connects the valve needle inlet 111 with the second valve port 121, and connects the valve seat 110 inlet 111 and the first valve port 112, that is, the second valve needle 140 moves axially relative to the first valve needle 120 through the limiting cavity 123, so that the opening of the second valve port 121 changes; continues to move, the second valve needle 140 drives the first valve needle 120 to move axially and the opening of the first valve port 112 changes; that is, the first valve needle 120 moves upward, so that the valve seat 110 inlet 111 and the first valve port 112 are connected.

[0055] In this solution, the pressing sleeve 150 and the first valve needle 120 are fixed by riveting, thereby reducing the high precision requirement of the pressing sleeve 150 and the first valve needle 120 and reducing the manufacturing cost; it also avoids the deformation of the sealing ring 103 that may be caused by welding, resulting in internal leakage failure, thereby improving product reliability, reducing component costs, and improving product market competitiveness.

[0056] The end of the first valve needle 120 is recessed inward to form an accommodating cavity 122, which is communicated with the limiting cavity 123. The pressing sleeve 150 is installed in the accommodating cavity 122. The end of the first valve needle 120 is provided with a first rivet 124, which is riveted and fixed to the pressing sleeve 150.

[0057] Reference Figure 5 In one embodiment, the end of the first valve needle 120 is recessed inward to form an accommodating cavity 122, the accommodating cavity 122 is connected to the limiting cavity 123, the pressing sleeve 150 is installed in the accommodating cavity 122, and the end of the first valve needle 120 is provided with a first rivet 124, and the first rivet 124 is riveted and fixed to the pressing sleeve 150.

[0058] The first valve needle 120 is arranged at the edge of the cavity opening of the accommodating cavity 122. In order to ensure the fixing effect, the upper surface of the pressing sleeve 150 is higher than the edge of the cavity opening of the accommodating cavity 122, and the end of the first rivet 124 is higher than the upper surface of the pressing sleeve 150. Through the riveting process, the first rivet 124 is fixed together with the pressing sleeve 150 to ensure the stability of the valve needle assembly. In order to ensure the riveting effect, the first rivet 124 is 0.3mm-1mm higher than the upper surface of the pressing sleeve 150. The first rivet 124 is an annular structure, which refers to a structure with a shape similar to a ring or a circular ring, characterized by having a closed circular or approximately circular contour. This structure is usually symmetrical and has no obvious starting or ending point in the circumferential direction; that is, the first rivet 124 is arranged in the accommodating cavity 122 of the first valve needle 120.

[0059] In one embodiment, the first rivet 124 and the pressing sleeve 150 are riveted by flanging; or by dot-punching deformation riveting.

[0060] Specifically, the first valve needle 120 is made of metal, such as aluminum alloy or copper alloy. In order to facilitate the installation of the pressing sleeve 150, a chamfer 125 is set at the end of the inner hole of the first rivet 124 of the first valve needle 120, and the chamfer 125 of the first rivet 124 is set between 15°-30°, and the length of the chamfer 125 is set between 0.3mm-1mm. In order to ensure the stability of the riveting and facilitate the riveting fixation, the wall thickness of the first rivet 124 is between 0.1mm-0.2mm, and in order to facilitate the bending of the first rivet 124, the outer wall of the first rivet 124 and the outer wall of the first valve needle 120 are arc-shaped transitions 126, and the radius of the arc The accommodating cavity 122 of the first valve needle 120 and the pressing sleeve 150 are clearance-matched, and the clearance is between 0.05mm and 0.15mm. In this way, there is a certain clearance between the pressing sleeve 150 and the accommodating cavity 122, which is convenient for installation but not too loose. In order to avoid burrs and noise, the pressing sleeve 150 is made of plastic. Specifically, the pressing sleeve 150 is made of PPS plastic material, and 10%-30% of glass fiber can be added. With the addition of glass fiber, the small valve needle can play a self-lubricating role during movement, prevent jamming and failure, and eliminate metal friction noise. The pressing sleeve 150 is integrally formed by injection molding.

[0061] In summary, the fixing of the press sleeve 150 by riveting has the following advantages: first, riveting does not require tight fitting, which can reduce the dimensional tolerance accuracy of parts and components and reduce the cost of processing and manufacturing; second, riveting does not require welding, eliminates the welding process, reduces the cost of parts and components, improves the market competitiveness of products, saves energy and is environmentally friendly, and solves the problem of internal leakage failure caused by deformation of the sealing ring 103 due to welding, thereby improving product reliability; in addition, the press sleeve 150 is made of PPS plastic material and has glass fiber added, so that during the movement of the second valve needle 140 relative to the first valve needle 120, the press sleeve 150 can play a self-lubricating role, on the one hand preventing the second valve needle 140 and the press sleeve 150 from being stuck and failing due to burrs or impurities, and on the other hand eliminating metal friction noise.

[0062] Reference Figures 1 to 3 The first valve needle 120 needs to be always at the farthest end of the screw rod 190 under the elastic force of the reset spring 170, and the structural positioning of the reset spring 170 is very critical. An unreasonable structural design may cause the reset spring 170 to get stuck and fail to move. For this reason, the utility model also improves the fixing structure of the reset spring 170.

[0063] Reference Figure 3Specifically, the nut assembly 160 is connected to the valve seat 110, the screw rod 190 passes through the nut assembly 160 and is connected to the second valve needle 140 through a guide sleeve, and the return spring 170 is sleeved on the outer wall of the second valve needle 140. One end of the return spring 170 abuts against the nut assembly 160, and the other end abuts against the pressing sleeve 150. In order to facilitate the positioning of the return spring 170, the end of the pressing sleeve 150 is recessed inward to form a sinking step 151. A first mounting groove 152 is formed between the outer wall of the second valve needle 140 and the sinking step 151. One end of the return spring 170 abuts against the nut assembly 160, and the other end is arranged in the first mounting groove 152.

[0064] Reference Figure 4 The pressing sleeve 150 is a hollow cylindrical shape, the upper end of the pressing sleeve 150 is recessed to form a sinking step 151, and the return spring 170 is an ordinary coil spring; the outer wall of the second valve needle 140 cooperates with the side wall of the sinking step 151 to form a first mounting groove 152; the end of the return spring 170 is arranged in the first mounting groove 152.

[0065] In order to ensure stable installation of the reset spring 170, the depth of the sinking step 151 is ≥1mm and not greater than half the depth of the pressing sleeve 150. In order to facilitate the installation of the reset spring 170 and avoid the problem of the reset spring 170 getting stuck during the deformation process, the gap between the outer wall of the reset spring 170 and the sinking step 151 is 0.1mm-0.2mm; the gap between the inner wall of the reset spring 170 and the outer wall of the second valve needle 140 is 0.5mm-1mm; the nut assembly 160 is a nested combination of injection molded parts. In order to achieve the fixing effect of the reset spring 170, the end of the nut assembly 160 is recessed inwardly relative to the pressing sleeve 150 to form a second installation groove 161, and one end of the reset spring 170 is arranged in the second installation groove 161, and the reset spring 170 is installed between the first valve needle 120, the pressing sleeve 150 and the nut assembly 160 The nut assembly 160 is provided with a hollow inner hole for the screw rod 190 to pass through, and the hollow inner hole is connected to the second mounting groove 161, and the diameter of the hollow inner hole is smaller than the inner diameter of the reset spring 170. In order to avoid affecting the fixing effect of the reset spring 170, the diameter of the hollow inner hole is smaller than the inner diameter of the reset spring 170 by more than 0.5 mm.

[0066] In summary, the positioning structure of the reset spring 170 provided by the utility model is simple and reliable. The first mounting groove 152 is formed by the recessed sinking step 151 of the pressing sleeve 150 and the outer wall of the second valve needle 140. One end of the reset spring 170 is arranged in the first mounting groove 152, and the outer circle of the reset spring 170 and the side wall of the sinking step 151 of the pressing sleeve 150 are matched with a small gap, which can not only ensure the positioning accuracy and ensure that the reset spring 170 does not shift, but also ensure that the reset spring 170 will not get stuck during the compression and resetting process. The reset spring 170 and the outer wall of the second valve needle 140 are matched with a large gap, which can ensure that the valve will never get stuck to the second valve needle 140 during the rotation process, thereby ensuring the normal operation of the valve. Finally, a second mounting groove 161 is set at the bottom end of the nut assembly 160, and the reset spring 170 is installed in the positioning inner hole of the second mounting groove 161. The inner diameter of the reset spring 170 is much larger than the inner diameter of the hollow inner hole of the nut assembly 160, ensuring that the reset spring 170 will not deviate or even get stuck in the hollow inner hole, causing the valve to get stuck.

[0067] Reference Figures 5 to 12 In addition, the second valve needle 140 needs to move up and down axially within a certain distance range in the limiting cavity 123 of the first valve needle 120. In order to ensure the sealing of the first valve needle 120 and the second valve needle 140, a sealing groove 127 is provided at the axial hole of the first valve needle 120 for the installation of the sealing ring 103. During the up and down movement of the second valve needle 140 through the axial hole, the sealing ring 103 is used to seal to ensure the sealing between the two to prevent the leakage here from connecting with the upper cavity of the first valve needle 120 and causing leakage. A valve needle gasket 102 is also provided above the sealing ring 103. The sealing ring 103 installed in the sealing groove 127 provides a dynamic seal. As the second valve needle 140 moves, the sealing ring 103 can maintain a good sealing effect to prevent refrigerant leakage; the valve needle gasket 102 is located above the sealing groove 127, and its main function is to further enhance the sealing to prevent the refrigerant from leaking from the gap between the valve needle and the valve body. In addition, the gasket can also provide a certain buffer, reduce the direct contact between the second valve needle 140 and the first valve needle 120, and reduce wear.

[0068] The traditional limit structure usually adopts the method of fitting the valve needle gasket 102 and the first valve needle 120 tightly and then welding them together. The valve needle gasket 102 is a thin-walled metal part. After stamping, the inner hole and the outer circle are prone to cutting edges, flash or burrs. During the process of fitting and pressing the valve needle gasket 102 and the first valve needle 120 tightly, it is easy to cause iron filings to the sealing ring 103, scratching the sealing ring 103, and then affecting the seal, causing leakage, affecting the system energy efficiency, and even system failure. More seriously, the iron filings entering the system will cause the system to get stuck or even the compressor to fail, seriously affecting reliability. In addition, the valve needle gasket 102 and the first valve needle 120 are prone to generate heat during the welding process, which is transferred to the sealing ring 103, causing the sealing ring 103 to deform due to heat, causing leakage, and affecting the system energy efficiency. The inner hole flange of the valve needle gasket 102 may also scratch the inner wall of the second valve needle 140, affecting the seal between the first valve needle 120, the second valve needle 140 and the sealing ring 103. In addition, the welding process requires large investment in equipment and has high process costs. The welding process is prone to generate smoke and harmful gases, polluting the environment.

[0069] Therefore, the utility model also improves the fixing method of the sealing gasket.

[0070] Reference Figure 5 and Figure 6 and Fig.11 and Fig.12 The bottom wall of the limiting cavity 123 is provided with a second rivet 128, a gasket groove 129 with a reduced inner diameter, and a sealing groove 127. The sealing ring 103 is arranged in the sealing groove 127. The valve needle gasket 102 is installed in the gasket groove 129 and is located above the sealing groove 127. The second rivet 128 is riveted and fixed to the valve needle gasket 102. In one embodiment, the second rivet 128 and the valve needle gasket 102 are flanged riveted; in one embodiment, the second rivet 128 and the valve needle gasket 102 are dotted and deformed riveted. In order to ensure the riveting effect, a plurality of second rivets 128 are provided. The method of providing a plurality of second rivets 128 is more convenient for processing. The flanging riveting is to bend the second rivet 128 to fix the valve needle gasket 102; the dotted and deformed riveting is to make the end of the second rivet 128 exceed the wall thickness by knocking, forming a mushroom shape.

[0071] In order to ensure the riveting effect, the upper surface of the valve needle gasket 102 is higher than the edge of the groove of the gasket groove 129, and the end of the second rivet 128 is higher than the upper surface of the valve needle gasket 102. The valve needle gasket 102 is fastened in the gasket groove 129 by flanging riveting or dot deformation riveting to achieve axial limitation; the height of the installation groove of the sealing ring 103 is greater than the wire diameter of the sealing ring 103, which is convenient for the installation of the sealing ring 103, and the valve needle gasket 102 is a hollow annular sheet. In order to avoid burrs and damage to the second valve needle 140, the valve needle gasket 102 is formed by injection molding. In order to facilitate the installation of the valve needle gasket 102, the outer circle of the valve needle gasket 102 and the gasket groove 129 adopt a clearance fit, and the fitting clearance is 0.05mm-0.15mm.

[0072] The end of the second rivet 128 protrudes from the upper surface of the valve needle gasket 102 by 0.5mm-1mm, and the wall thickness of the second rivet 128 is set between 0.1mm-0.3mm. In the scheme of achieving riveting by dot deformation, the deformation part of the dotted part is set at the center of the matching part between the inner hole of the large valve needle and the outer circle of the large valve needle gasket 102; in order to ensure the effect of dot riveting, the dot diameter is ≥1mm; two, three or four second rivets 128 are set.

[0073] Reference Figure 7 and Figure 8 and Fig. 9 and Fig.10 In one embodiment, a sealing groove 127 is provided on the bottom wall of the limiting cavity 123, and the sealing ring 103 is arranged in the sealing groove 127. The valve needle gasket 102 is installed in the limiting cavity 123 and is located above the sealing groove 127. The end of the side wall of the pressing sleeve 150 abuts against the valve needle gasket 102. During installation, the sealing ring 103 is placed in the sealing groove 127, and the valve needle gasket 102 is placed to the notch of the sealing groove 127. The pressing sleeve 150 is covered, and the side wall of the pressing sleeve 150 abuts against the surface of the valve needle gasket 102 to press the valve needle gasket 102, thereby fixing the sealing ring 103 and limiting the sealing ring 103.

[0074] In summary, the valve needle gasket 102 is fixed by riveting, the first large valve needle of the valve needle gasket 102 can be matched with a small gap, the dimensional tolerance accuracy of the parts can be appropriately relaxed, the processing cost of the parts is reduced, and then the overall cost of the product is reduced, which is conducive to reducing product costs and improving market competitiveness; and the valve needle gasket 102 can be made of plastic material and formed by injection molding, which solves the problem of flash burrs that may exist in metal gaskets scratching the sealing ring 103 or the second valve needle 140, preventing leakage and system failure and jamming. In addition, the riveting process replaces welding, which also solves the problem of thermal deformation; the injection-molded valve needle gasket 102 itself has self-lubricating properties, which avoids scratching the second valve needle 140 and improves product reliability.

[0075] The utility model also provides a refrigeration device, which includes an electronic expansion valve 100. The specific structure of the electronic expansion valve 100 refers to the above embodiment. Since the refrigeration device adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here. The refrigeration device can be an air conditioning system of a vehicle.

[0076] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An electronic expansion valve, characterized in that: include: A valve seat having a first valve port; a first valve needle and a second valve needle, wherein the first valve needle sleeves the second valve needle, the first valve needle is disposed in a valve seat, and the first valve needle has a second valve port; and A pressing sleeve, wherein the pressing sleeve is riveted to the first valve needle, and a limiting cavity is provided between the pressing sleeve and the first valve needle, and the second valve needle moves axially relative to the first valve needle to change the opening of the second valve port; the second valve needle moves in the limiting cavity and drives the first valve needle by abutting against the pressing sleeve to change the opening of the first valve port.

2. The electronic expansion valve according to claim 1, characterized in that: The electronic expansion valve also includes a return spring and a nut assembly connected to the valve seat. The return spring is sleeved with the second valve needle. The end of the compression sleeve is recessed inward to form a sinking step. A first mounting groove is formed between the outer wall of the second valve needle and the sinking step. One end of the return spring abuts against the nut assembly, and the other end is arranged in the first mounting groove.

3. The electronic expansion valve according to claim 2, characterized in that: The depth of the sunken step is ≥1mm.

4. The electronic expansion valve according to claim 2, characterized in that: The gap between the outer wall of the return spring and the sinking step is 0.1mm-0.2mm.

5. The electronic expansion valve according to claim 2, characterized in that: The gap between the inner wall of the return spring and the outer wall of the second valve needle is 0.5 mm-1 mm.

6. The electronic expansion valve according to claim 2, characterized in that: The end of the nut assembly is recessed inwardly relative to the pressing sleeve to form a second installation groove, and one end of the return spring is arranged in the second installation groove.

7. The electronic expansion valve according to claim 1, characterized in that: The end of the first valve needle is recessed inward to form an accommodating cavity, the accommodating cavity is communicated with the limiting cavity, the pressing sleeve is installed in the accommodating cavity, and the end of the first valve needle is provided with a first rivet, and the first rivet is fixed to the pressing sleeve by riveting.

8. The electronic expansion valve according to claim 7, characterized in that: The upper surface of the pressing sleeve is higher than the edge of the cavity opening of the accommodating cavity, and the end of the first rivet part is higher than the upper surface of the pressing sleeve.

9. The electronic expansion valve according to claim 8, characterized in that: The first rivet is 0.3 mm to 1 mm higher than the upper surface of the pressing sleeve.

10. The electronic expansion valve according to claim 7, characterized in that: The first rivet member is an annular structure, and an inner end of the first rivet member is provided with a chamfer.

11. The electronic expansion valve according to claim 10, characterized in that: An arc-shaped transition is formed between the outer side wall of the first rivet member and the outer side wall of the first valve needle.

12. The electronic expansion valve according to claim 7, characterized in that: The diameter of the accommodating cavity is greater than the diameter of the limiting cavity, and the edge portion of the pressing sleeve is located in the limiting cavity.

13. The electronic expansion valve according to claim 7, characterized in that: The gap between the outer wall of the pressing sleeve and the inner wall of the accommodating cavity is 0.05mm-0.15mm.

14. The electronic expansion valve according to claim 1, characterized in that: The electronic expansion valve also includes a valve needle gasket and a sealing ring. The bottom wall of the limiting cavity is provided with a second rivet, and a gasket groove and a sealing groove with reduced inner diameters. The sealing ring is arranged in the sealing groove. The valve needle gasket is installed in the gasket groove and is located above the sealing groove. The second rivet is riveted and fixed to the valve needle gasket.

15. The electronic expansion valve according to claim 14, characterized in that: The upper surface of the valve needle gasket is higher than the notch edge of the gasket groove, and the end of the second rivet member is higher than the upper surface of the valve needle gasket.

16. The electronic expansion valve according to claim 15, characterized in that: The height of the second rivet is 0.3 mm-1 mm; and / or the wall thickness of the second rivet is 0.1 mm-0.3 mm.

17. The electronic expansion valve according to claim 14, characterized in that: The second rivet member and the valve needle gasket are connected by flanging rivets; or, the second rivet member and the valve needle gasket are connected by dot-punching deformation rivets.

18. The electronic expansion valve according to claim 17, characterized in that: There are a plurality of second rivet members.

19. The electronic expansion valve according to claim 1, characterized in that: The electronic expansion valve also includes a valve needle gasket and a sealing ring. The bottom wall of the limiting cavity is provided with a sealing groove, and the sealing ring is arranged in the sealing groove. The valve needle gasket is installed in the limiting cavity and is located above the sealing groove. The end of the side wall of the pressing sleeve abuts against the valve needle gasket.

20. The electronic expansion valve according to claim 14 or 19, characterized in that: The compression sleeve is integrally formed by injection molding; and / or the valve needle gasket is integrally formed by injection molding.

21. A refrigeration device, characterized in that: Comprising the electronic expansion valve as claimed in any one of claims 1 to 20.

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