Electronic expansion valve

Abstract

The utility model provides an electronic expansion valve which comprises a first connecting pipe, a silencing part, a valve seat part and an adapting part, the valve seat part and the adapting part are connected with each other, the adapting part is respectively connected with the valve seat part and the first connecting pipe, the adapting part is provided with a containing cavity, and the silencing part is installed in the containing cavity in a limited mode. By the adoption of the scheme, the furnace welding object of the first connecting pipe is converted from the valve seat part to the switching part through the switching part, when the switching part and the first connecting pipe are subjected to furnace welding, the silencing part located in the containing cavity is separated from the first connecting pipe through the switching part, the first connecting pipe does not directly abut against the silencing part, welding flux generated during furnace welding cannot permeate into the silencing part, and the silencing effect is good. And the noise reduction effect of the noise reduction part and the flow capacity of the electronic expansion valve are ensured. And on the other hand, independent off-line installation of the switching part and the silencing part can be achieved, the production takt is reduced, part standardization is improved, the falling risk in the part turnover process is avoided, and the machining and installation efficiency of the electronic expansion valve is improved.

Description

Technical Field

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

[0002] At present, electronic expansion valves can be used in the field of series reheat dehumidification. Since the electronic expansion valve is set between two indoor heat exchangers in this application, this determines that under normal air-conditioning conditions, the pressure drop of the electronic expansion valve at a large opening must be small enough to ensure the capacity of the air-conditioning system; and since the electronic expansion valve is set on the indoor side, the requirement for noise is also high. Based on this, a porous silencer can be set at the valve port of the electronic expansion valve to reduce the noise of refrigerant circulation.

[0003] Electronic expansion valves usually use a first connecting pipe to directly press the silencer into the cavity of the valve seat. One end of the first connecting pipe extends into the cavity of the valve seat and directly abuts against the silencer located in the cavity of the valve seat. Since furnace welding is usually used for the installation of the first connecting pipe, that is, the first connecting pipe is directly connected to the valve seat by furnace welding, the solder easily penetrates into the silencer from the gap between the inner wall of the cavity of the valve seat and the outer periphery of the first connecting pipe during furnace welding. The silencer is a porous structure, and the solder easily adheres to the silencer after flowing to the silencer, thereby causing partial blockage of the silencer and affecting the noise reduction effect and flow capacity. Furthermore, since the silencer is usually pressed into the valve seat, the valve seat needs to be processed into a corresponding cavity for installing the silencer. The processing requirements are high and there are many factors to consider. On the other hand, there is also a risk of parts falling off during the press-fitting process, affecting the processing and installation efficiency. Utility Model Content

[0004] The utility model provides an electronic expansion valve to solve the problem in the prior art that a muffler portion is easily blocked by furnace welding solder, thereby affecting the noise reduction effect, and improve the processing and installation efficiency of the electronic expansion valve.

[0005] In order to solve the above problems, the utility model provides an electronic expansion valve, which includes a first connecting pipe, a silencer, and a valve seat portion and a transition portion connected to each other. The transition portion is respectively connected to the valve seat portion and the first connecting pipe. The transition portion has an accommodating cavity, and the silencer portion is limitedly installed in the accommodating cavity.

[0006] Further, the silencer is laser welded in the accommodating cavity, or the silencer is riveted in the accommodating cavity, or the silencer is press-fitted in the accommodating cavity.

[0007] Furthermore, the valve seat portion also has a limiting cavity, the transition portion includes a matching section, at least part of the matching section is arranged in the limiting cavity, an inner step surface is provided between the cavity inner wall of the fixed section and the cavity inner wall of the matching section, and the silencer portion abuts against the inner step surface.

[0008] Further, the fitting section includes a first fitting section and a second fitting section connected to each other. At least part of the first fitting section extends into the limiting cavity, and at least part of the second fitting section is located outside the limiting cavity for connecting the first connecting pipe. The outer diameter of the first fitting section is larger than that of the second fitting section, and the inner diameter of the first fitting section is larger than that of the second fitting section.

[0009] Further, there is an outer stepped surface between the outer wall of the first fitting section and the outer wall of the second fitting section. The outer stepped surface protrudes from the limiting cavity or is flush with the surface where the opening of the limiting cavity is located to form a positioning reference surface.

[0010] Further, an annular stop protrusion is provided inside the connecting section. The annular stop protrusion is arranged between the first fitting section and the second fitting section and protrudes inward in the radial direction of the connecting section. The inner diameter of the annular stop protrusion is smaller than that of the second fitting section. The area surrounded by the annular stop protrusion forms a transfer port. One end of the first connecting pipe is arranged inside the second fitting section and is in stop cooperation with the annular stop protrusion. The transfer port is communicated with the opening of the first connecting pipe.

[0011] Further, the transfer port is a straight section with a constant inner diameter along the axial direction of the electronic expansion valve, or the transfer port is a first flared opening, or the side of the transfer port away from the first connecting pipe has a first flared opening. The inner diameter of the first flared opening gradually increases along the direction from the first connecting pipe towards the transfer port. The side with a smaller opening of the first flared opening is communicated with the first connecting pipe and the radial dimension is adapted to the inner diameter of the first connecting pipe. The opening angle of the first flared opening is β, and 20° ≤ β ≤ 120°.

[0012] Further, there is a riveted flanging at the opening of the accommodating cavity, and the connecting section and the sound-absorbing section are in riveted cooperation.

[0013] Further, the riveted flanging is an annular flanging, or there are multiple riveted flangings, and the multiple riveted flangings are distributed at intervals along the circumferential direction of the connecting section.

[0014] Further, the connecting section includes a fixed section. The area surrounded by the fixed section forms an accommodating cavity. In the axial direction of the fixed section, the part where the opening side of the fixed section protrudes from the sound-absorbing section forms a riveted flanging.

[0015] Further, the valve seat part includes a valve seat and a valve seat core. The valve seat has an installation cavity. The valve seat core is arranged in the installation cavity. The area of the installation cavity for installing the valve seat core forms a placement cavity, and the area of the installation cavity for installing the connecting section forms a limiting cavity.

[0016] Further, the valve seat core is separated from the valve seat, and the valve seat core is arranged in the placement cavity of the valve seat; or the valve seat core and the valve seat are of an integral structure.

[0017] Further, the valve seat portion has a valve cavity, which is located on the side of the accommodation cavity away from the adapter portion. The valve cavity communicates with the accommodation cavity and includes a valve port section. The valve port section is a variable-diameter flow adjustment section, or, on the side of the valve port section away from the accommodation cavity, there is a variable-diameter flow adjustment section.

[0018] Further, the flow adjustment section is a second flared opening, and the opening angle of the second flared opening is α, where 1° ≤ α ≤ 10°.

[0019] Further, the electronic expansion valve further includes a valve needle assembly. The valve needle assembly includes a valve head member, and the valve head member cooperates with the inner wall of the flow adjustment section to adjust the flow of the electronic expansion valve. When the electronic expansion valve is fully closed, one end of the valve head member extends into the valve port section, and there is a gap between the outer periphery of the valve head member and the inner wall of the valve port section.

[0020] Further, the electronic expansion valve further includes a rotor assembly. The valve needle assembly further includes a screw member drivingly connected to the rotor assembly. The inner wall of the valve port section has a first tapered section and a first straight section that communicate with each other and are arranged in sequence along the direction of the valve cavity towards the first connection pipe. The first tapered section is the flow adjustment section. When the electronic expansion valve is fully closed, one end of the valve head member is located in the first tapered section, and there is a gap between the outer periphery of the valve head member and the inner wall of the first tapered section. The height of the first tapered section is H5, and the distance from the end of the valve head member to the connection surface of the first tapered section and the first straight section is H9. The electronic expansion valve has a flow turning point with a changing flow slope during the valve opening process; B*n*γ / 360 + H9 = H5; where B is the number of supply pulses required for the valve head member to open the valve from the fully closed position to the flow turning point, n is the pitch of the screw member, and γ is the step angle of the rotor assembly.

[0021] Further, the electronic expansion valve further includes a rotor assembly. The valve needle assembly further includes a screw member drivingly connected to the rotor assembly. The inner wall of the valve port section has a first tapered section and a first straight section that communicate with each other and are arranged in sequence along the direction of the valve cavity towards the first connection pipe. The first tapered section is the flow adjustment section. When the electronic expansion valve is fully closed, one end of the valve head member is located in the first tapered section, and there is a gap between the outer periphery of the valve head member and the inner wall of the first straight section. The height of the first tapered section is H5, and the distance from the end of the valve head member to the connection surface of the first tapered section and the first straight section is H9. The electronic expansion valve has a flow turning point with a changing flow slope during the valve opening process; B*n*γ / 360 – H9 = H5; where B is the number of supply pulses required for the valve head member to open the valve from the fully closed position to the flow turning point, n is the pitch of the screw member, and γ is the step angle of the rotor assembly.

[0022] By applying the technical solution of the utility model, an electronic expansion valve is provided, which includes a first connecting pipe, a silencer, and a valve seat portion and a transition portion connected to each other. The transition portion is respectively connected to the valve seat portion and the first connecting pipe, and the transition portion has a accommodating cavity. The silencer is limitedly installed in the accommodating cavity.

[0023] By adopting this scheme, the furnace welding object of the first pipe is changed from the valve seat part to the adapter part through the adapter part. When the adapter part and the first pipe are furnace welded, the muffler part located in the accommodating cavity and the first pipe are separated by the adapter part, and the first pipe does not directly contact the muffler part. Even if the solder generated during furnace welding penetrates, it will not penetrate into the muffler part. This avoids the situation in the prior art that when the first pipe is directly furnace welded with the valve seat part, the solder easily penetrates into the muffler part from the gap between the two, thereby affecting the noise reduction effect of the muffler part and the flow capacity of the electronic expansion valve, thereby ensuring the noise reduction effect of the muffler part and the flow capacity of the electronic expansion valve. On the other hand, this scheme can realize the independent off-line installation of the muffler part through the adapter part. The operator only needs to adapt the adapter part to the valve seat part and the muffler part when processing it, and then install the connected adapter part and the muffler part together on the valve seat part. This arrangement is conducive to reducing the production cycle, improving the standardization of parts, avoiding the risk of falling during the turnover of parts, and improving the processing and installation efficiency of the electronic expansion valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0025] Figure 1 The structure diagram of the electronic expansion valve provided in the first embodiment of the present utility model is shown;

[0026] Figure 2 Shows Figure 1 A magnified view of position A in the middle;

[0027] Figure 3 Shows Figure 2 A magnified view of position B in the middle;

[0028] Figure 4 Shows Figure 2 Schematic diagram of the structure of the middle valve seat;

[0029] Figure 5 Shows Figure 2 Assembly diagram of the middle valve seat core, silencer and adapter;

[0030] Figure 6 Shows Figure 2 A schematic diagram of the structure of the intermediate transfer part;

[0031] Figure 7 Shows Figure 1 A schematic diagram of the structure of the electronic expansion valve when the valve is closed;

[0032] Figure 8 Shows Figure 7 Enlarged view of the C position in the middle;

[0033] Figure 9 Shows Figure 7 Flow diagram of

[0034] Figure 10 A partial structural schematic diagram of a valve seat of an electronic expansion valve provided in Embodiment 2 of the present utility model is shown;

[0035] Figure 11 The figure shows an assembly diagram of a valve seat core, a muffler part and a transfer part of an electronic expansion valve provided in the second embodiment of the present utility model;

[0036] Figure 12 A partial enlarged view of the electronic expansion valve provided in the second embodiment of the utility model is shown;

[0037] Figure 13 The schematic diagram of the structure of the electronic expansion valve provided in the third embodiment of the present utility model when the valve is closed is shown;

[0038] Figure 14 Shows Figure 13 Enlarged view of the D position in the middle;

[0039] Figure 15 Shows Figure 13 Flow diagram of .

[0040] The above drawings include the following reference numerals:

[0041] 1. Annular groove;

[0042] 10. Valve seat; 101. Installation cavity; 1011. Limiting cavity; 1012. Placement cavity; 102. Valve cavity; 1021. Valve mouth section; 10211. First tapered section; 10212. First straight-through section; 10213. Second tapered section; 10214. Second straight-through section; 1022. Expanding section; 11. Valve seat; 12. Valve seat core; 121. First loose-fit section; 122. First tight-fit section;

[0043] 20, transfer part; 201, accommodating cavity; 2011, first limiting cavity section; 2012, second limiting cavity section; 202, outer step surface; 203, transfer interface; 204, inner step surface; 21, first matching section; 22, second matching section; 23, annular stop protrusion; 24, fixing section; 241, riveted flange;

[0044] 30. Silencing unit; 31. First silencing block; 32. Pad block; 33. Second silencing block;

[0045] 41. First takeover; 42. Second takeover;

[0046] 50. Nut assembly;

[0047] 60. Valve needle assembly; 61. Valve head component; 62. Screw component;

[0048] 70. Guide sleeve; 71. First sleeve; 72. Second sleeve; 73. Limit sleeve;

[0049] 80. Rotor assembly. DETAILED DESCRIPTION

[0050] 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. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0051] like Figures 1 to 15 As shown, an embodiment of the utility model provides an electronic expansion valve, which includes a first connecting pipe, a silencer portion 30, and a valve seat portion 10 and a connecting portion 20 that are interconnected. The connecting portion 20 is respectively connected to the valve seat portion 10 and the first connecting pipe 41. The connecting portion 20 has a accommodating cavity 201, and the silencer portion 30 is limitedly installed in the accommodating cavity 201.

[0052] The muffler 30 can be laser welded in the accommodating cavity 201, or riveted in the accommodating cavity 201, or press-fitted in the accommodating cavity 201. The adapter 20 includes a fixing section 24, and the area surrounded by the fixing section 24 forms the accommodating cavity 201.

[0053] In this embodiment, the adapter part 20 is connected to the valve seat part 10 and the first connecting pipe 41 at both ends along the axial direction of the electronic expansion valve, respectively. The adapter part 20 allows the furnace welding object of the first connecting pipe 41 to be changed from the valve seat part 10 to the adapter part 20. When the adapter part 20 and the first connecting pipe 41 are furnace-welded, the muffler 30 located in the accommodating cavity is separated from the first connecting pipe 41 by the adapter part 20. The first connecting pipe 41 does not directly abut the muffler 30. During furnace welding, the molten solder will not penetrate into the muffler 30, thereby avoiding the situation where the first connecting pipe 41 directly abuts against the muffler 30. When the first connecting pipe 41 and the valve seat part 10 are furnace-welded, the molten solder is easy to penetrate into the muffler 30 from the gap between the two, thereby affecting the noise reduction effect of the muffler 30 and the flow capacity of the electronic expansion valve, thereby ensuring the noise reduction effect of the muffler 30 and the flow capacity of the electronic expansion valve. On the other hand, the present solution can realize independent off-line installation of the muffler 30 through the adapter 20. The operator only needs to adapt the adapter 20 to the valve seat 10 and the muffler 30 when processing it, and then install the connected adapter 20 and the muffler 30 together on the valve seat 10. This arrangement is conducive to reducing the production cycle, improving the standardization of parts, avoiding the risk of falling during the turnover of parts, and is conducive to improving the processing and installation efficiency of the electronic expansion valve.

[0054] It should be noted that the adapter 20 can be a drawn part, a precision-machined part, etc. In this embodiment, since multiple steps and flow channels need to be machined inside the adapter 20, and the adapter 20 needs to be press-fitted into the valve seat 10, there are high requirements for the dimensional accuracy of the adapter 20, so the adapter 20 in this embodiment is preferably a precision-machined part. It is understandable that the adapter 20 can be precision-machined as a whole, or stamped first and then precision-machined (the step portion is precision-machined), or cold-forged first and then precision-machined.

[0055] like Figure 1 , Figure 2 , Figure 5 and Figure 6 As shown, the opening of the accommodating cavity 201 has a riveted flange 241, and the adapter 20 is riveted to the muffler 30. In this way, the muffler 30 is riveted by the riveted flange 241, which is convenient for design and processing, has a reliable limiting effect, and is conducive to improving installation efficiency.

[0056] In this embodiment, the riveted flange 241 is an annular flange, or there are multiple riveted flanges 241, and the multiple riveted flanges 241 are distributed at intervals along the circumference of the transition part 20. This arrangement can ensure the reliability and stability of the limited installation of the muffler 30.

[0057] like Figure 6As shown, the adapter 20 includes a fixing section 24, and the area surrounded by the fixing section 24 forms a receiving cavity 201. In the axial direction of the fixing section 24, the portion of the opening side of the fixing section 24 protruding from the muffler 30 forms a riveted flange 241. This arrangement facilitates the integrated processing of the receiving cavity 201 and the riveted flange 241, which is conducive to improving the processing and installation efficiency.

[0058] Preferably, the accommodating chamber 201 includes a first limiting chamber section 2011 and a second limiting chamber section 2012 that are interconnected. Along the axial direction of the electronic expansion valve, the second limiting chamber section 2012 is located on a side of the accommodating chamber 201 away from the first connecting pipe 41, and the first limiting chamber section 2011 is located on a side of the accommodating chamber close to the first connecting pipe 41. The radial dimension of the second limiting chamber section 2012 is smaller than the radial dimension of the first limiting chamber section 2011. Specifically, as Figure 2 and Figure 5 As shown, the muffler 30 includes a first muffler block 31, a cushion block 32, and a second muffler block 33 which are sequentially abutted along the installation direction of the muffler 30. The outer diameter of the first muffler block 31 is adapted to the inner diameter of the first limiting cavity section 2011. The first muffler block 31 is arranged in the first limiting cavity section 2011 and is limitedly matched with the inner wall of the first limiting cavity section 2011. The outer diameter of the second muffler block 33 is adapted to the inner diameter of the second limiting cavity section 2012. The second muffler block 33 is arranged in the second limiting cavity section 2012 and is limitedly matched with the inner wall of the second limiting cavity section 2012. This arrangement can facilitate the distinction between the first muffler block 31 and the second muffler block 33, avoid the wrong installation order, and prevent the installation positions of the two muffler blocks from being confused, which is conducive to improving the installation efficiency of the muffler 30. Preferably, the cushion block 32 in this embodiment is an annular structure.

[0059] It can be understood that the installation direction of the silencer 30 is to install the silencer 30 in the accommodating cavity 201 in a direction parallel to the axial direction of the electronic expansion valve. The installation direction in this embodiment is the axial direction of the electronic expansion valve from the first limiting cavity section 2011 to the second limiting cavity section 2012.

[0060] Among them, the first silencer block 31 and the second silencer block 33 are both provided with a circulation area and a decomposition area, wherein at least a part of the circulation area provided on the first silencer block 31 is provided corresponding to the decomposition area provided on the second silencer block 33, and at least a part of the circulation area provided on the second silencer block 33 is provided corresponding to the decomposition area provided on the first silencer block 31.

[0061] Preferably, in the axial direction of the electronic expansion valve, the height of the first silencer block 31 is H31, the height of the cushion block 32 is H32, and the height of the second silencer block is H33, (H31+H32+H33) is the overall height of the silencer portion 30 in the axial direction of the electronic expansion valve, the height of the first limiting cavity section 2011 is H62, the height of the second limiting cavity section 2012 is H61, (H61+H62) is the overall height of the accommodating cavity 201 in the axial direction of the electronic expansion valve, wherein H61≤H33, that is, along the axial direction of the electronic expansion valve, the second silencer block 33 is not lower than the opening of the second limiting cavity section 2012. Specifically, H61<H33, that is, the second muffler block 33 protrudes from the opening of the second limiting cavity section 2012; or H61=H33, that is, the second muffler block 33 is flush with the surface where the opening of the second limiting cavity section 2012 is located, so as to ensure the abutment effect between the pad block 32 and the second muffler block 33, preferably H61<H33, and preferably 0.01mm≤(H33-H61)≤0.7mm. On the other hand, (H31+H32+H33)<(H61+H62) is used to ensure the forming of the riveted flange 241.

[0062] It can be understood that (H61+H62) in this embodiment is the actual height of the fixed section 24 after the riveted flange 241 of the fixed section 24 is riveted to the silencer 30, which is smaller than the initial height of the fixed section 24 before riveting.

[0063] In this embodiment, the valve seat portion 10 also has a limiting cavity 1011, and the transition portion 20 includes a fixed section 24 and a mating section that are connected to each other. The fixed section 24 and at least part of the mating section are arranged in the limiting cavity 1011. The inner diameter of the fixed section 24 is larger than the inner diameter of the mating section. An inner step surface 204 is provided between the inner wall of the cavity of the fixed section 24 and the inner wall of the cavity of the mating section, and the muffler portion 30 abuts against the inner step surface 204.

[0064] In this way, the installation depth of the silencer 30 is limited by the inner step surface 204, so that the two ends of the silencer 30 along the axial direction of the electronic expansion valve are clamped between the inner step surface 204 and the riveted flange 241; on the other hand, the limiting cavity 1011 facilitates the limiting installation of the adapter 20, thereby ensuring the reliability of the installation of the adapter 20.

[0065] like Figures 1 to 15 As shown, the valve seat portion 10 includes a valve seat 11 and a valve seat core 12, the valve seat 11 has an installation cavity 101, and the valve seat core 12 is arranged in the installation cavity 101. Specifically, the valve seat core 12 is press-fitted in the installation cavity, and the area of the installation cavity 101 used for installing the valve seat core 12 forms a placement cavity 1012, and the area of the installation cavity 101 used for installing the adapter 20 forms a limiting cavity 1011. This arrangement facilitates the division of the limiting cavity 1011 and the installation of the valve seat core 12.

[0066] In this embodiment, the valve seat 11 and the valve seat core 12 are separately arranged, and the valve seat core 12 is pressed into the placement cavity 1012 of the valve seat 11; or in other embodiments not shown in the figure, the valve seat 11 and the valve seat core 12 can also be an integrated structure to form the valve seat part 10.

[0067] The valve seat core 12 of the valve seat portion 10 also has a valve cavity 102, and the valve cavity 102 is located on the side of the accommodating chamber 201 away from the adapter portion 20, and the valve cavity 102 is connected to the accommodating chamber 201. It should be noted that in the series reheat dehumidification system, the electronic expansion valve is arranged between the two indoor heat exchangers, which determines that under normal air-conditioning conditions, the pressure drop of the electronic expansion valve at a large opening is as small as possible to ensure the energy efficiency of the air-conditioning system, and the indoor side has high requirements for noise. Therefore, it is necessary to set a silencer structure (corresponding to the silencer portion 30 in this embodiment) at the valve port (corresponding to the valve cavity 102 in this embodiment). In order to reduce the throttling of the porous silencer structure, the area of the porous silencer structure can be increased and a large-diameter electronic expansion valve can be used. In the related art, one end of the pipe (corresponding to the first pipe 41 in the present embodiment) directly extends into the valve seat (corresponding to the valve seat 11 in the present embodiment) and directly abuts against the muffler 30, and the end of the pipe extending into the valve seat must have a larger outer diameter; and in the series reheat dehumidification system, the electronic expansion valve is mainly used in 1-3p units, and the inner diameter of the corresponding indoor heat exchanger connecting pipeline is smaller than that of the units above 3P. The other end of the electronic expansion valve pipe is connected to the indoor heat exchanger connecting pipeline, which determines that the inner diameter of the other end of the pipe is smaller. The pipe diameters at both ends of the electronic expansion valve pipe are inconsistent and the span is large. The solution of the pipe abutting the muffler mechanism makes the pipe consist of three or more pipes with different diameters. This type of pipe is difficult to process and has high cost.

[0068] In view of the above problems, in this embodiment, the mating section includes a first mating section 21 and a second mating section 22 that are connected to each other. The first mating section 21 is connected to the fixed section 24. At least a part of the first mating section 21 extends into the limiting cavity 1011, and at least a part of the second mating section 22 is located outside the limiting cavity 1011 for connecting the first connecting pipe 41. The outer diameters of the first mating section 21 and the fixed section 24 are both larger than the outer diameter of the second mating section 22. Preferably, the outer diameter of the first mating section 21 is equal to or slightly larger than the outer diameter of the fixed section 24; the inner diameter of the first mating section 21 is larger than the inner diameter of the second mating section 22. By defining the dimensions (inner diameter and outer diameter) of the first mating section 21 and the second mating section 22, the adapter section 20 can be adapted to valve seat sections 10 of different sizes. At the same time, the reduction of the radial dimension of the second mating section 22 is equivalent to forming a necking at the adapter section 20 itself. Therefore, the end of the first connecting pipe 41 connected to the adapter section 20 does not need to be reduced in diameter to adapt to the large-diameter valve seat section 10. Only the appropriate raw material needs to be selected according to the diameter of the electronic expansion valve to process the first connecting pipe 41, so as to reduce the processing difficulty of the first connecting pipe 41 and improve the processing efficiency.

[0069] It can be understood that the other end of the first connecting pipe 41 is connected to the system pipeline. Whether the other end of the first connecting pipe 41 connected to the system pipeline is necked, flared, or not processed depends on the actual situation. Compared with the situation where the first connecting pipe 41 is directly connected to the valve seat section 10 in the prior art, the end of the first connecting pipe 41 connected to the electronic expansion valve saves at least one flaring process through the adapter section 20.

[0070] Preferably, at least a part of the outer wall of the valve seat core 12 is in interference fit with the inner wall of the placement cavity 1012, and at least a part of the outer wall of the adapter section 20 extending into the limiting cavity 1011 is in interference fit with the inner wall of the limiting cavity 1011.

[0071] Specifically, as Figures 1 to 9In the first embodiment shown, the valve seat core 12 includes a first loose-fitting section 121 and a first tight-fitting section 122 that are connected to each other. In this embodiment, the first tight-fitting section 122, the fixing section 24, and the first mating section 21 are all straight cylindrical sections. The outer diameter of the first loose-fitting section 121 gradually decreases in the direction of the first connecting pipe 41 towards the valve cavity 102. At least part of the first tight-fitting section 122 is in interference fit with the inner wall of the placement cavity 1012. The first mating section 21 extends into the limiting cavity 1011, and part or all of the outer wall of the first mating section 21 is in interference fit with the inner wall of the limiting cavity 1011. Through the setting of the first loose-fitting section 121, it is convenient for the valve seat core 12 to be inserted and guided during installation, avoiding the high pressing difficulty caused by the overlong interference fit section. Further, in this embodiment, the inner diameters of the placement cavity 1012 and the limiting cavity 1011 are the same, which is D1. The outer diameters of the first tight-fitting section 122, the fixing section 24, and the first mating section 21 are the same, which is D2, and D2 = D1 or D2 is slightly larger than D1 to ensure the interference fit of the first tight-fitting section 122 in the installation cavity 101 and the requirements of installation coaxiality. Preferably, D2 is slightly larger than D1.

[0072] Preferably, as Figures 10 to 12 shown, the second embodiment of the present utility model provides an electronic expansion valve. The difference from the first embodiment is that, as Figure 9 shown, the inner diameter D11 of the placement cavity 1012 is smaller than the inner diameter D12 of the limiting cavity 1011. As Figure 11 shown, the outer diameter of the first loose-fitting section 121 is D21, the outer diameter of the first tight-fitting section 122 is D22, the outer diameter of the fixing section 24 is D23, and the outer diameter of the first mating section 21 is D24. D21 is smaller than D11, D23 is smaller than D12, D22 is equal to D11 or slightly larger than D11, and D24 is equal to D12 or slightly larger than D12 to ensure the reliability of the interference fit and the requirements of installation coaxiality.

[0073] It can be understood that the interference length between the valve seat core 12 or the adapter part 20 and the installation cavity 101 can be adjusted according to the actual situation.

[0074] In this embodiment, the bottom wall of the first mating section 21 is an outer stepped surface 202, and the outer stepped surface 202 is located between the outer walls of the first mating section 21 and the second mating section 22. As Figure 12 shown, the outer stepped surface 202 between the outer wall of the first mating section 21 and the outer wall of the second mating section 22 protrudes from the limiting cavity 1011 and forms a positioning reference surface. Or, as Figure 3As shown, the outer stepped surface 202 between the outer walls of the first mating section 21 and the second mating section 22 is flush with the surface where the opening of the limiting cavity 1011 is located and forms a positioning reference surface. With this arrangement, compared with the case where the valve seat portion 10 is directly connected to the first nozzle 41 and the end face of the valve seat portion 10 facing the opening of the first nozzle 41 is used as the positioning reference surface, the area of the positioning reference surface is increased. And due to the setting of the adapter portion 20, the placement position of the welding ring for furnace welding the first nozzle 41 is far from the positioning reference surface, and during furnace welding, there will be no situation where the solder melts and spreads on the positioning reference surface, resulting in insufficient positioning reference dimensions and inaccurate positioning. There is almost no impact on the positioning reference and it will not affect the positioning during subsequent assembly and welding.

[0075] The adapter portion 20 and the valve seat portion 10, and the adapter portion 20 and the first nozzle 41 can be respectively connected by welding. Specifically, the adapter portion 20 and the valve seat portion 10 can be connected by laser welding, and the adapter portion 20 and the first nozzle 41 can be connected by furnace welding, brazing or other welding methods. In this embodiment, the adapter portion 20 and the valve seat portion 10 are laser welded, and the adapter portion 20 and the first nozzle 41 are furnace welded. As Figure 3 shown and Figure 12 shown, a circumferential weld is formed between the bottom of the first mating section 21 and the bottom of the valve seat 11 where the opening of the limiting cavity 1011 is located. With this arrangement, it is possible to avoid the situation where the second nozzle 42 interferes with the welding when the laser welding position is formed on the side of the electronic expansion valve.

[0076] The bottom wall of the first mating section 21 can be flush with the bottom wall of the valve seat 11; specifically, in Figures 1 to 9In the first embodiment shown, the sound-absorbing part 30 is riveted inside the fixed section 24, the valve seat core 12 is press-fitted on the bottom wall of the placement cavity 1012, and the end of the fixed section 24 extending into the valve seat 11 abuts against the valve seat core 12. In the axial direction of the electronic expansion valve, the height of the installation cavity 101 is H1, and the sum of the height of the valve seat core 12, the height of the first mating section 21 of the adapter section 20, and the height of the fixed section 24 of the adapter section 20 is H2 (wherein, the height of the fixed section 24 is based on the actual height after the riveting flange 241 presses the sound-absorbing part 30, that is, H61 + H62), H1 = H2, and the bottom wall of the first mating section 21 is flush with the bottom wall of the valve seat 11. Further, in order to avoid the situation where the height of the laser welding mark after welding is too high, the bottom wall of the first mating section 21 and / or the bottom wall of the valve seat 11 has an annular groove 1 at the annular weld. The area within the annular groove 1 can be used as the annular weld, and the laser welding mark formed after welding will be entirely or mostly located within the annular groove 1, achieving the hiding of the laser welding mark after welding, so that the laser welding mark formed by laser welding will not protrude from the positioning reference surface or the influence of the protruding part on the positioning reference effect of the positioning reference surface is almost non-existent, and it will not affect the positioning during subsequent assembly and welding, so as to ensure the reliability of welding and the reliability of the positioning reference surface.

[0077] Preferably, the cross-sectional shape of the annular groove 1 can be adaptively adjusted according to the actual situation, and is not limited to the triangle in this embodiment.

[0078] The bottom wall of the first mating section 21 can protrude from the bottom wall of the valve seat 11, so that there is a gap between the bottom wall of the first mating section 21 and the bottom wall of the valve seat 11 in the axial direction, which is convenient for laser welding focusing. Specifically, Figures 10 to 12In the second embodiment shown, the sound-absorbing portion 30 is riveted inside the fixed section 24. The valve seat core 12 is press-fitted on the bottom wall of the placement cavity 1012. One end of the fixed section 24 extending into the valve seat 11 abuts against the valve seat core 12. In the axial direction of the electronic expansion valve, the height of the installation cavity 101 is less than the sum of the heights of the valve seat core 12, the first fitting section 21 of the adapter section 20, and the fixed section 24, that is, the bottom wall of the first fitting section 21 protrudes from the bottom wall of the valve seat 11. Specifically, the height of the placement cavity 1012 is H11, the height of the limiting cavity 1011 is H12, and the height of the installation cavity 101 is H1, where H1 = H11 + H12. The sum of the heights of the valve seat core 12, the height of the first fitting section 21 of the adapter section 20, and the height of the fixed section 24 of the adapter section 20 is H2 (where the height of the fixed section 24 is based on the actual height after the riveting flange 241 presses the sound-absorbing portion 30, that is, H61 + H62), and H1 < H2. The bottom wall of the first fitting section 21 protrudes from the bottom wall of the valve seat 11. In this case, the positioning reference surface is spaced from the weld position, which is convenient for the laser welding to focus here. Among them, the height by which the bottom wall of the first fitting section 21 protrudes from the bottom wall of the valve seat 11 is H8, and H8 = H2 - H1, where 0.1 mm < H8 < 1 mm. By limiting H8, the laser welding marks formed after welding will not protrude from the positioning reference surface, or the protruding part has almost no influence on the positioning reference effect of the positioning reference surface, and it will not affect the positioning during the subsequent assembly and welding.

[0079] It can be understood that the fixing method of the sound-absorbing portion 30 in the adapter section 20 of the present application is not limited to riveting. The sound-absorbing portion 30 can be directly fixed in the adapter section 20 by laser welding or the first sound-absorbing block 31 of the sound-absorbing portion 30 protrudes from the adapter section 20, and the protruding part of the first sound-absorbing block 31 abuts against the valve seat portion 10 at one end along the axial direction of the electronic expansion valve, etc.

[0080] As Figure 1 、 Figure 2 、 Figure 5 and Figure 11 shown, the adapter section 20 has an annular stop protrusion 23. The annular stop protrusion 23 is arranged between the first fitting section 21 and the second fitting section 22 and protrudes inward in the radial direction. The inner diameter of the annular stop protrusion 23 is smaller than the inner diameter of the second fitting section 22. The area surrounded by the annular stop protrusion 23 forms an adapter opening 203. One end of the first connection pipe 41 is arranged in the second fitting section 22 and is in stop cooperation with the annular stop protrusion 23. The adapter opening 203 is communicated with the opening of the first connection pipe 41. In this embodiment, one end of the first connection pipe 41 penetrates into the second fitting section 22 and abuts against the annular stop protrusion 23. The penetration depth of the first connection pipe 41 is limited by the annular stop protrusion 23, and the outer diameter of the first connection pipe 41 is adapted to the inner diameter of the second fitting section 22.

[0081] In this embodiment, the inner diameter of the first connecting pipe 41 is adapted to the radial dimension of the transfer interface 203, facilitating the limited installation of the first connecting pipe 41 and the formation of the transfer interface 203. Meanwhile, a smooth transition of the refrigerant flowing through the transfer interface 203 and the first connecting pipe 41 is achieved, reducing the flow noise of the refrigerant.

[0082] Wherein, the transfer interface 203 is a straight section with a constant inner diameter along the axis direction of the electronic expansion valve, or the transfer interface 203 is a first flared mouth, or one side of the transfer interface 203 facing away from the first connecting pipe 41 has a first flared mouth, and the inner diameter of the first flared mouth gradually increases along the direction of the first connecting pipe 41 towards the valve cavity 102. The side with a smaller opening of the first flared mouth is connected to the first connecting pipe 41 and the radial dimension is adapted to the inner diameter of the first connecting pipe 41. The opening angle of the first flared mouth is β, and 20° ≤ β ≤ 120°. Specifically, as Figure 5 and Figure 11 shown, the transfer interface 203 in this embodiment includes a first flared mouth and a straight section that are interconnected. By setting the first flared mouth, on the one hand, it can ensure that there are no burrs here (the transfer part 20 is a precision machined part, and burrs are likely to be generated here in the case of a straight flow channel); on the other hand, a second connecting pipe 42 is also connected to the side wall of the valve seat 11 of the electronic expansion valve. When the fluid enters from the first connecting pipe 41 and exits from the second connecting pipe 42, since the inner diameter of the first flared mouth gradually increases along the direction of the first connecting pipe 41 towards the valve cavity 102, it provides a buffering effect for the fluid entering from the first connecting pipe 41, is not easy to form eddy currents, realizes a gradual change in pressure, reduces the flow rate, and reduces the impact of the high-speed fluid on the filter screen, that is, reduces the flow rate of the refrigerant entering the valve port position, reduces the turbulent kinetic energy, and thus reduces the noise.

[0083] Preferably, the height of the first flared mouth is H7, and 0.1mm ≤ H7 ≤ 3mm. The inner diameter of the small opening of the first flared mouth close to the first connecting pipe 41 is as close as possible to the inner diameter of the first connecting pipe 41, and the difference between the two does not exceed 5%.

[0084] Specifically, the flow curve of the electronic expansion valve provided in this embodiment is designed as a sharp-opening broken line type and has a flow turning point. The flow rate is gentle and the flow rate value is small at a small opening degree to meet the adjustment under the dehumidification working condition. The flow rate is large at a large opening degree to meet the flow capacity under the normal air-conditioning working condition and reduce the pressure drop.

[0085] The valve orifice cavity 102 includes a valve orifice section 1021 and a flared section 1022 that communicate with each other. The valve orifice section 1021 has a flow regulation section, and the flow regulation section communicates with the accommodation cavity 201 through the flared section 1022. The electronic expansion valve further includes a valve needle assembly 60. The flow regulation section is located at one end of the valve orifice section 1021 close to the valve needle assembly 60. The valve needle assembly 60 includes a valve head member 61, and the valve head member 61 can approach or move away from the valve orifice cavity 102 along the axial direction of the electronic expansion valve and cooperate with the flow regulation section to adjust the flow rate of the electronic expansion valve. It should be noted that the electronic expansion valve provided in this embodiment is of the type with a flow line in the fully closed state. When the whole valve is in the fully closed state, there is a gap between the outer periphery of the valve head member 61 and the inner wall of the valve orifice section 1021, and the refrigerant can flow between the two connecting pipes (the first connecting pipe 41 and the second connecting pipe 42) through the gap. At this time, the electronic expansion valve has a flow rate, and the flow rate value is greater than the internal leakage amount specified by the industry standard for the corresponding caliber. It can be understood that the specific implementation of having a flow in the fully closed state is achieved by the axial upward movement of the valve head member 61 after finding the zero point by a fixed pulse, and the flow in the fully closed state is realized through the gap between the valve head member 61 and the valve orifice section 1021 when fully closed.

[0086] As Figures 6 to 9 shown in Embodiment 1, the valve needle assembly 60 further includes a screw member 62, and the electronic expansion valve further includes a rotor assembly 80 for driving the screw member 62. The inner wall of the valve orifice section 1021 of the present application has a first tapered section 10211 and a first straight section 10212 that communicate with each other and are arranged in sequence along the direction of the valve orifice cavity 102 facing the first connecting pipe 41. Among them, the first tapered section 10211 is the flow regulation section, and the first straight section 10212 communicates with the flared section 1022. The valve head member 61 cooperates with the inner wall of the first tapered section 10211 to adjust the flow rate of the electronic expansion valve. The height of the first tapered section 10211 is H5. When the electronic expansion valve is fully closed, the distance from the end of the valve head member 61 to the connecting surface of the first tapered section 10211 and the first straight section 10212 is H9. During the valve opening process of the electronic expansion valve, there is a flow turning point with a changing flow slope. The flow turning point here is the point when the end of the valve head member 61 facing the valve orifice cavity 102 just disengages from the first tapered section 10211; B*n*γ / 360 + H9 = H5; where B is the number of supply pulses required for the valve head member 61 to move away from the fully closed position in the direction away from the valve orifice cavity 102 and open the valve until it just disengages from the first tapered section 10211 (flow turning point), n is the pitch of the screw member 62, and γ is the step angle of the rotor assembly 80. As Figures 7 to 9As shown, in this embodiment, the fully closed position is located on the first tapered section 10211. That is, when the electronic expansion valve is in the fully closed position, the end of the valve head member 61 facing one end of the valve cavity 102 is located within the first tapered section 10211 and above the first straight-through section 10212, and there is a gap between the valve head member 61 and the inner wall of the first tapered section 10211. The flow curve has no flat section after 0 pulses and slopes upward directly from 0 pulses.

[0087] The overall flow regulation section is a second flared opening, and the side with the larger opening of the second flared opening faces away from the first connection pipe 41. In this embodiment, the first tapered section 10211 is the second flared opening, and the opening angle of the second flared opening is α, where 1° ≤ α ≤ 10°. The slope of the broken line before and after the flow turning point is different. The flow curve before the flow turning point is gentle, and the slope of the broken line after the flow turning point is larger, corresponding to a larger flow rate. When the electronic expansion valve is fully open, the flow resistance is small. Under the dehumidification working condition, the required flow rate is small. If this angle is too large, the flow rate at a small opening will be too large to meet the requirements of the whole machine for the dehumidification working condition. If this angle is too small, it will interfere with the outer diameter of the valve head member 61. By limiting the angle α, it is beneficial to ensure the flow rate value and stability of the electronic expansion valve at a small opening. Preferably, 1° ≤ α ≤ 6°. The number of supply pulses required for the valve head member 61 to reach the flow turning point from the fully closed position can be achieved by setting the height H5 of the first tapered section 10211. H5 can be customized according to the requirements of the customer's whole machine (ensuring that the turning point of the flow curve is between 300P - 400P under normal circumstances). Specifically, 2.5 mm ≤ H5 ≤ 7 mm.

[0088] Among them, the unit of B is pulse or step, and the value of B can be customized according to customer requirements. After the value of B is determined, the corresponding height H5 of the first tapered section 10211 can be determined; it can be understood that, as Figure 7 shown in Embodiment 1, the maximum diameter of the first tapered section 10211 is D41, the minimum diameter of the first tapered section 10211 is the same as the diameter of the first straight-through section 10212 and is both D2. α or H5 can be calculated by tanα / 2 = [(D41 - D42) / 2] / H5, and the unit of n is mm; γ is related to the number of pole pairs of the valve body. For 1 - 2 phase excitation and 10 pole pairs of the rotor, the step angle γ = 4.5°; for 1 - 2 phase excitation and 12 pole pairs of the rotor, the step angle γ = 3.75°; for 2 - 2 phase excitation and 10 pole pairs of the rotor, the step angle γ = 9°; for 2 - 2 phase excitation and 12 pole pairs of the rotor, the step angle γ = 7.5°; γ / 360 is the number of pulses required for the valve head to rotate one circle.

[0089] As Figures 13 to 15As shown in the figure, Embodiment 3 of the present utility model provides an electronic expansion valve. The difference from Embodiment 1 is that the inner wall of the valve port section 1021 of this embodiment has a first tapered section 10211, a first straight section 10212, a second tapered section 10213, and a second straight section 10214 that are sequentially connected along the direction of the valve cavity 102 towards the first connection pipe 41.

[0090] In this embodiment, when the electronic expansion valve is in the fully closed state, the end of the valve head part 61 is located in the first straight section 10212, and there is a gap between the outer periphery of the valve head part 61 and the first straight section 10212. At this time, the first tapered section 10211 plays a role in flow regulation, and the following second tapered section 10213 has no effect on flow regulation. Specifically, the first tapered section 10211 is the flow regulation section. In the fully closed position, the end of the valve head part 61 facing the valve cavity 102 is located within the first straight section 10212. The height of the first tapered section 10211 is H5, and the depth of the valve head part 61 extending into the first straight section 10212 is H9. Then B * n * γ / 360 – H9 = H5. As Figures 13 to 15 shown, in this embodiment, the fully closed state with flow is achieved through the gap between the valve head part 61 and the first straight section 10212. The fully closed position is located on the first straight section 10212. Since in this embodiment, the outer wall of the part of the valve head part 61 extending into the valve cavity 102 is a straight line segment, during the process of the valve head part 61 moving away from the valve cavity 102 from the fully closed position, the size of the gap between the outer wall of the valve head part 61 and the inner wall of the first straight section 10212 remains unchanged. Therefore, there is a flat section in the flow curve after 0 pulses. When the end of the valve head part 61 facing the valve cavity 102 leaves the first straight section 10212 and enters the first tapered section 10211, the flow curve starts to slope upward after the flat section. Since the fully closed position falls on the first straight section 10212, the gap between the valve head part 61 and the straight section can be controlled smaller when fully closed, and the risk of the valve head part 61 getting stuck with the valve port section 1021 is smaller, so as to achieve the regulation of a smaller flow rate under the dehumidification working condition. In this embodiment, the second tapered section 10213 is used for the fixed pulse of the electronic expansion valve, that is, during the installation of the electronic expansion valve, first abut the valve head part 61 against the second tapered section 10213, and then move the valve head part 61 axially upward by a certain distance so that the end face of the valve head part 61 facing the valve cavity 102 enters the first straight section 10212.

[0091] As Figure 14 and Figure 15 shown, in this embodiment, the fully closed state with flow is achieved through the gap between the valve head part 61 and the first straight section 10212. The fully closed position is located on the first straight section 10212, and there is a flat section in the flow curve after 0 pulses, and then it starts to slope upward after the flat section.

[0092] Of course, in other embodiments of the present application where the figures are not shown, the valve seat core 12 and the valve seat 11 can also be integrally formed into a valve seat portion 10. The valve cavity 102 is located within the integral valve seat portion 10, and the valve cavity 102 has the aforementioned valve port section 1021. In this embodiment, except that the valve seat core 12 and the valve seat 11 are integrally provided, the implementation methods and flow curves of other fully closed flows are the same as those in the foregoing embodiments and will not be elaborated herein.

[0093] It can be understood that according to the position of the end of the valve head member 61 when closing the valve (including but not limited to the first tapered section 10211, the first straight section 10212, the second tapered section 10213, and the second straight section 10214 in this embodiment), the formula of tanα / 2 and the formula between H5 and H9 can be adaptively adjusted accordingly, and no examples will be given one by one here.

[0094] Specifically, when the electronic expansion valve is in the fully open mode, the flow coefficient Cv≥1, where V is the maximum flow rate of the electronic expansion valve, G is the specific gravity of the medium flowing through the electronic expansion valve, P1 is the pressure on the inflow side of the electronic expansion valve, and P2 is the pressure on the outflow side of the electronic expansion valve. The Cv value is the flow coefficient of the electronic expansion valve, representing the flow capacity when the electronic expansion valve provided in the present application is fully open. When the Cv value is less than 1, it means that there will still be a certain throttling effect on the fluid flowing through when the electronic expansion valve is fully open, that is, it shows that the flow capacity of the electronic expansion valve in the fully open state is insufficient, affecting the fluid flow between the indoor heat exchangers and thus affecting the performance of the whole machine. In the present application, by setting Cv≥1, the flow capacity of the electronic expansion valve can be ensured, and it is ensured that the flow capacity of this valve meets the requirements of the whole machine performance when used under normal operating conditions of the air conditioner.

[0095] The electronic expansion valve further comprises a second connecting pipe 42, a nut assembly 50, a valve needle assembly 60 and a guide sleeve 70, and the following assembly process can be adopted: one end of the second connecting pipe 42 is welded to the side of the valve seat portion 10; the first connecting pipe 41 is welded to the end of one end of the adapter portion 20; the muffler 30 is installed in the adapter portion 20, a part of the adapter portion 20 is installed in the valve seat portion 10, the adapter portion 20 is welded to the valve seat portion 10, and the nut assembly 50 and the valve needle assembly are sequentially installed on the valve seat portion 10. Assembly 60; and before sequentially installing the nut assembly 50 and the valve needle assembly 60 on the valve seat 10, the process of welding one end of the second connecting pipe 42 to the side of the valve seat 10 also includes: first press-fitting the guide sleeve 70 into the valve seat 10, and integrally furnace-welding the second connecting pipe 42, the valve seat 10 and the guide sleeve 70, or first furnace-welding the second connecting pipe 42 and the valve seat 10, and then press-fitting the guide sleeve 70 into the valve seat 10, and laser-welding the guide sleeve 70 and the valve seat 10, and pulse-setting the electronic expansion valve. This arrangement can realize the independent off-line installation of the adapter 20 and the muffler 30, which is conducive to reducing the production cycle, improving the standardization of parts, avoiding the risk of falling during the turnover of parts, facilitating the assembly of the electronic expansion valve, and improving the assembly efficiency.

[0096] The end of one end of the adapter part 20 is the end of the adapter part 20 located outside the valve seat part 10 , and the first connecting pipe 41 is welded to the end of the adapter part 20 located outside the valve seat part 10 .

[0097] Preferably, the order of the steps of "welding one end of the second connecting pipe 42 to the side of the valve seat portion 10", "welding the first connecting pipe 41 to the end of one end of the adapter portion 20", and "installing the muffler 30 in the adapter portion 20" is not limited.

[0098] Specifically, the silencer part 30 includes a first silencer block 31, a cushion block 32 and a second silencer block 33 which are sequentially abutted along the installation direction of the silencer part 30. The process of installing the silencer part 30 in the adapter part 20 also includes: installing the second silencer block 33, the cushion block 32 and the first silencer block 31 in sequence in the adapter part 20.

[0099] Similarly, the first connecting pipe 41 is first welded to the end of the adapter part 20 outside the valve seat part 10, and then the muffler part 30 is installed in the adapter part 20; or, the muffler part 30 is first installed in the adapter part 20, and then the adapter part 20 and the first connecting pipe 41 are welded.

[0100] Furthermore, in this embodiment, the valve seat portion 10 includes a split valve seat 11 and a valve seat core 12 , and the assembly process also includes the step of disposing the valve seat core 12 in the valve seat 11 , and one end of the adapter portion 20 extends into the valve seat 11 and abuts against the valve seat core 12 .

[0101] It can be understood that in another embodiment not shown in the figures, the valve seat portion 10 includes an integral valve seat 11 and a valve seat core 12, and at this time, there is no need to include the installation step of the valve seat core 12. Or in yet another embodiment not shown in the figures, the valve seat portion 10 includes a split valve seat 11 and a valve seat core 12, and the silencing portion 30 abuts against the valve seat core 12.

[0102] Wherein, in this embodiment, the adapter portion 20 and the valve seat portion 10 are connected by laser welding.

[0103] Preferably, the guide sleeve 70 in this embodiment is smaller at the top and larger at the bottom. The nut assembly 50 includes a nut member. The guide sleeve 70 includes a first sleeve 71, a limiting sleeve 73, and a second sleeve 72 that are sequentially connected. The limiting sleeve 73 is used to limit the position of the guide sleeve 70 in the valve seat 11. The outer diameters of the first sleeve 71, the second sleeve 72, and the limiting sleeve 73 increase sequentially. The inner diameters of the first sleeve 71 and the limiting sleeve 73 are the same and larger than the inner diameter of the second sleeve 72. The outer periphery of the second sleeve 72 is in interference fit with the inner hole of the nut member to ensure their coaxiality. The inner cavity of the first sleeve 71 is used to pass through the valve head member 61 and is in clearance fit with the outer periphery of the valve head member 61, and the clearance is 0.01 mm - 0.1 mm.

[0104] Since the outer diameter of the connecting main pipe of the indoor heat exchanger of the current mainstream household 3P split cabinet air conditioner is mostly Φ9.0 or Φ8.0, taking the outer diameter of Φ9.0 as an example, the wall thickness is mostly 0.75 mm, that is, the inner diameter is Φ7.5. Therefore, the valve port must be > Φ7.5 mm to ensure that there is no excessive pressure drop when the valve is fully open, so as to ensure the overall performance of the machine; preferably, 7 mm ≤ the minimum diameter of the valve cavity 102 ≤ 9.5 mm.

[0105] It should be noted that the terms used here are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used here, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0106] Unless otherwise specifically stated, the relative arrangements, numerical expressions, and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present utility model. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said technologies, methods, and devices should be regarded as part of the description. In all the examples shown and discussed here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0107] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by orientation terms such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal", and "top, bottom", etc. are generally based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Without contrary statements, these orientation terms do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and thus should not be construed as limiting the protection scope of the present utility model; the orientation terms "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0108] For the convenience of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above" etc. can be used here to describe the spatial positional relationships between a device or feature shown in the drawings and other devices or features. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the drawings of the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0109] In addition, it should be noted that the use of words such as "first", "second", etc. to limit components is only for the convenience of differentiating the corresponding components. Without additional statements, the above words have no special meanings, and thus should not be construed as limiting the protection scope of the present utility model.

[0110] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, the present utility model may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An electronic expansion valve, characterized in that, The electronic expansion valve includes a first connection pipe (41), a silencing part (30), and a valve seat part (10) and an adapter part (20) that are connected to each other. The adapter part (20) is respectively connected to the valve seat part (10) and the first connection pipe (41). The adapter part (20) has a receiving cavity (201), and the silencing part (30) is installed in the receiving cavity (201) in a limited position.

2. The electronic expansion valve according to claim 1, characterized in that, The silencing part (30) is laser welded in the receiving cavity (201), or the silencing part (30) is riveted in the receiving cavity (201), or the silencing part (30) is press-fitted in the receiving cavity (201).

3. The electronic expansion valve according to claim 1, wherein The valve seat part (10) has a limiting cavity (1011). The adapter part (20) includes a fitting section. At least part of the fitting section is arranged in the limiting cavity (1011). There is an inner stepped surface (204) between the inner wall of the cavity of the receiving cavity (201) and the inner wall of the cavity of the fitting section. The silencing part (30) abuts against the inner stepped surface (204).

4. The electronic expansion valve according to claim 3, characterized in that, The fitting section includes a first fitting section (21) and a second fitting section (22) that are connected to each other. At least part of the first fitting section (21) extends into the limiting cavity (1011). At least part of the second fitting section (22) is located outside the limiting cavity (1011) for adapting the first connection pipe (41). The outer diameter of the first fitting section (21) is larger than the outer diameter of the second fitting section (22), and the inner diameter of the first fitting section (21) is larger than the inner diameter of the second fitting section (22).

5. The electronic expansion valve according to claim 4, wherein, There is an outer stepped surface (202) between the outer wall of the first fitting section (21) and the outer wall of the second fitting section (22). The outer stepped surface (202) protrudes from the limiting cavity (1011) or is flush with the surface where the opening of the limiting cavity (1011) is located and forms a positioning reference surface.

6. The electronic expansion valve according to claim 4, wherein There is an annular stop protrusion (23) in the adapter part (20). The annular stop protrusion (23) is arranged between the first fitting section (21) and the second fitting section (22) and protrudes inward in the radial direction of the adapter part (20). The inner diameter of the annular stop protrusion (23) is smaller than the inner diameter of the second fitting section (22). The area surrounded by the annular stop protrusion (23) forms an adapter opening (203). One end of the first connection pipe (41) is arranged in the second fitting section (22) and is in stop cooperation with the annular stop protrusion (23). The adapter opening (203) is communicated with the opening of the first connection pipe (41).

7. The electronic expansion valve according to claim 6, wherein The adapter (203) is a straight section with a constant inner diameter along the axial direction of the electronic expansion valve, or the adapter (203) is a first flare, or the side of the adapter (203) facing away from the first connection pipe (41) has a first flare. The inner diameter of the first flare gradually increases along the direction from the first connection pipe (41) towards the adapter (203). The side with a smaller opening of the first flare communicates with the first connection pipe (41) and its radial dimension is adapted to the inner diameter of the first connection pipe (41). The opening angle of the first flare is β, and 20° ≤ β ≤ 120°.

8. The electronic expansion valve according to claim 1, wherein, A riveting flange (241) is provided at the opening of the accommodation cavity (201), and the adapter portion (20) is in riveting fit with the silencing portion (30).

9. The electronic expansion valve according to claim 8, characterized in that, The riveting flange (241) is an annular flange, or there are multiple riveting flanges (241), and the multiple riveting flanges (241) are spaced circumferentially along the adapter portion (20).

10. The electronic expansion valve according to claim 8, characterized in that, The adapter portion (20) includes a fixed section (24). The area surrounded by the fixed section (24) forms the accommodation cavity (201). In the axial direction of the fixed section (24), the part of the opening side of the fixed section (24) protruding from the silencing portion (30) forms the riveting flange (241).

11. The electronic expansion valve according to claim 1, wherein The valve seat portion (10) includes a valve seat (11) and a valve seat core (12). The valve seat (11) has an installation cavity (101). The valve seat core (12) is arranged in the installation cavity (101). The area of the installation cavity (101) for installing the valve seat core (12) forms a placement cavity (1012), and the area of the installation cavity (101) for installing the adapter portion (20) forms a limiting cavity (1011).

12. The electronic expansion valve according to claim 11, wherein, The valve seat core (12) is separated from the valve seat (11), and the valve seat core (12) is arranged in the placement cavity (1012) of the valve seat (11); or the valve seat core (12) and the valve seat (11) are of an integral structure.

13. The electronic expansion valve according to claim 1, wherein, The valve seat portion (10) has a valve orifice cavity (102). The valve orifice cavity (102) is located on the side of the accommodation cavity (201) facing away from the adapter portion (20). The valve orifice cavity (102) communicates with the accommodation cavity (201). The valve orifice cavity (102) includes a valve orifice section (1021). The valve orifice section (1021) is a variable-diameter flow regulation section, or the side of the valve orifice section (1021) facing away from the accommodation cavity (201) has a variable-diameter flow regulation section for regulating the flow rate of the electronic expansion valve.

14. The electronic expansion valve according to claim 13, wherein, The flow regulation section is a second flare, and the opening angle of the second flare is α, and 1° ≤ α ≤ 10°.

15. The electronic expansion valve according to claim 13, wherein, The electronic expansion valve further includes a valve needle assembly (60). The valve needle assembly (60) includes a valve head member (61). The valve head member (61) cooperates with the inner wall of the flow regulation section to adjust the flow rate of the electronic expansion valve. When the electronic expansion valve is fully closed, one end of the valve head member (61) extends into the valve port section (1021), and there is a gap between the outer periphery of the valve head member (61) and the inner wall of the valve port section (1021).

16. The electronic expansion valve according to claim 15, characterized in that, The electronic expansion valve further includes a rotor assembly (80). The valve needle assembly (60) further includes a screw member (62) drivingly connected to the rotor assembly (80). The inner wall of the valve port section (1021) has a first tapered section (10211) and a first straight section (10212) that are interconnected and arranged in sequence along the direction of the valve cavity (102) towards the first connection pipe (41). The first tapered section (10211) is the flow regulation section. When the electronic expansion valve is fully closed, one end of the valve head member (61) is located within the first tapered section (10211), and there is a gap between the outer periphery of the valve head member (61) and the inner wall of the first tapered section (10211); the height of the first tapered section (10211) is H5, and the distance from the end of the valve head member (61) to the connecting surface of the first tapered section (10211) and the first straight section (10212) is H9. The electronic expansion valve has a flow rate turning point with a changing flow rate slope during the valve opening process. B*n*γ / 360 + H9 = H5; Wherein, B is the number of supply pulses required for the valve head member (61) to open the valve from the fully closed position to the flow rate turning point, n is the pitch of the screw member (62), and γ is the step angle of the rotor assembly (80).

17. The electronic expansion valve according to claim 15, characterized in that, The electronic expansion valve further includes a rotor assembly (80). The valve needle assembly (60) further includes a screw member (62) drivingly connected to the rotor assembly (80). The inner wall of the valve port section (1021) has a first tapered section (10211) and a first straight section (10212) that are interconnected and arranged in sequence along the direction of the valve cavity (102) towards the first connection pipe (41). The first tapered section (10211) is the flow regulation section. When the electronic expansion valve is fully closed, one end of the valve head member (61) is located within the first tapered section (10211), and there is a gap between the outer periphery of the valve head member (61) and the inner wall of the first straight section (10212); the height of the first tapered section (10211) is H5, and the distance from the end of the valve head member (61) to the connecting surface of the first tapered section (10211) and the first straight section (10212) is H9. The electronic expansion valve has a flow rate turning point with a changing flow rate slope during the valve opening process. B*n*γ / 360 - H9 = H5; Wherein, B is the number of supply pulses required for the valve head member (61) to open the valve from the fully closed position to the flow turning point, n is the pitch of the screw member (62), and γ is the step angle of the rotor assembly (80).

Images