Electronic expansion valve

Abstract

An electronic expansion valve, comprising: a housing (10); a valve seat (20), the valve seat (20) having an installation cavity (23) and a valve cavity (21) in communication with each other, the valve cavity (21) being provided with a valve port (201), and the valve port (201) being located at the end of the valve cavity (21) away from the installation cavity (23); a rotor assembly (30), which is provided in the housing (10) and has a rotor cavity; a valve needle assembly (40), which is arranged in the housing (10), the valve needle assembly (40) being able to regulate a flow at the valve port (201) under driving of the rotor assembly (30); a guide sleeve (50), which is provided with a first section (51) and a second section (52) which are sequentially connected in the axial direction, the first section (51) being partially located in the housing (10), and the second section (52) being arranged in the installation cavity (23); a circulation channel (200), which is arranged in the second section (52) or the installation cavity (23), or said circulation channel (200) is arranged between the second section (52) and the installation cavity (23), one end of the circulation channel (200) being in communication with the valve cavity (21), and the other end being in communication with the rotor cavity; and when the electronic expansion valve is in a fully closed state, the distance between the side of a rotor connecting plate (32) close to the valve cavity (21) and the end of the circulation channel (200) close to the rotor cavity is H.

Description

Electronic expansion valve

[0001] This application claims priority to the patent application with application number 2023112840432, filed with the State Intellectual Property Office of China on September 29, 2023, and entitled “Electronic Expansion Valve”; and priority to the patent application with application number 2023226689890, filed with the State Intellectual Property Office of China on September 29, 2023, and entitled “Electronic Expansion Valve”. Technical Field

[0002] The present application relates to the technical field of control valves, and in particular to an electronic expansion valve. Background Art

[0003] The electronic expansion valve in the prior art mainly includes a valve needle assembly, a valve seat, a guide sleeve and a rotor assembly. The valve seat has a valve cavity and a valve port. The valve needle assembly can cooperate with the guide sleeve under the drive of the rotor assembly to approach or move away from the valve port, thereby adjusting the flow rate of the fluid at the valve port. When the fluid passes through the valve cavity of the valve seat, the valve seat will vibrate due to the impact of the fluid. At this time, the space inside the rotor assembly will resonate with the valve cavity, causing the fluid to generate resonance noise when flowing through the electronic expansion valve, affecting user use.

[0004] Summary of the Invention

[0005] The present application provides an electronic expansion valve to solve the problem in the prior art that the electronic expansion valve generates resonance noise during use.

[0006] The present application provides an electronic expansion valve, the electronic expansion valve comprising: a shell having an installation space; a valve seat, the valve seat having an installation cavity and a valve cavity that are interconnected, and a valve port being provided on the valve seat; a rotor assembly arranged in the shell, the rotor assembly comprising a magnetic rotor and a rotor connecting plate, the magnetic rotor being sleeved on the outer side of the rotor connecting plate, the magnetic rotor having a rotor cavity; a valve needle assembly arranged in the shell, the valve needle assembly being connected to the rotor connecting plate, the valve needle assembly being arranged corresponding to the valve port, and the valve needle assembly being capable of adjusting the flow at the valve port under the drive of the rotor assembly; a guide sleeve, the valve needle assembly being arranged through the guide sleeve, the guide sleeve having a first section and a second section connected in sequence along the axial direction, the first section being partially located in the shell, and the second section being arranged in the installation cavity; a flow channel arranged between the second section and / or the installation cavity, one end of the flow channel being connected to the valve cavity, and the other end of the flow channel being connected to the rotor cavity. When the electronic expansion valve is in a fully closed state, a distance H is between a side of the rotor connecting plate close to the valve cavity and an end of the flow channel close to the rotor cavity. Wherein, A is the flow area of ​​the flow channel, c is the air propagation velocity, L is the axial length of the second section, D1 is the diameter of the rotor cavity, and D2 is the diameter of the first section.

[0007] Applying the technical solution of the present application, the electronic expansion valve includes a shell, a valve seat, a rotor assembly, a valve needle assembly and a guide sleeve. By setting a flow channel to connect the valve cavity and the rotor cavity, the pressure in the valve cavity and the rotor cavity can be ensured to be consistent, which facilitates the rotor assembly to drive the valve needle assembly to rotate. However, this will cause the valve cavity and the rotor cavity to resonate when the fluid flows through the electronic expansion valve, thereby causing the fluid to generate a large noise when flowing through the electronic expansion valve. According to the Helmholtz resonance principle, when the relevant dimensions are designed according to the above formula, the resonant frequency of the rotor cavity and the valve cavity can be reduced to a level that the human ear can sensitively perceive, thereby reducing the noise generated by the fluid when flowing through the electronic expansion valve, ensuring the noise reduction effect, and improving the user experience comfort.

[0008] Furthermore, the sidewall of the second section has a cross-sectional structure, forming a flow channel between the cross-sectional structure and the inner wall of the mounting cavity. This arrangement allows fluid to enter the rotor cavity through the flow channel, ensuring pressure balance within the valve cavity and rotor cavity. It also reduces pressure fluctuations caused by small fluids flowing through the valve cavity, further reducing noise generated when fluids flow through the electronic expansion valve, and improving user comfort.

[0009] Furthermore, a flow hole is provided on the second section, and the flow hole forms a flow channel. In this way, the flow hole can connect the rotor cavity and the installation cavity, thereby reducing the working noise of the electronic expansion valve.

[0010] Furthermore, the valve needle assembly includes a first threaded segment and a first guide segment connected in sequence. The first guide segment is positioned near the valve port. The guide sleeve includes a second threaded segment and a second guide segment connected in sequence. The first and second threaded segments are threadedly engaged. The valve needle assembly rotates relative to the guide sleeve to move closer to or away from the valve port, and the first and second guide segments engage with each other for guidance. Through this arrangement, the first and second threaded segments engage with each other, and the first and second guide segments engage with each other, enabling movement and guidance of the valve needle assembly relative to the valve port, thereby improving the performance of the electronic expansion valve.

[0011] Furthermore, the guide sleeve includes a third section connected to the second section and located within the valve cavity, with the outer diameter of the third section being smaller than the outer diameter of the second section. This arrangement allows the guide sleeve to be axially limited within the mounting cavity, ensuring operational stability of the electronic expansion valve.

[0012] Furthermore, the diameter of the third section, which is located near the valve port, gradually decreases as it moves away from the rotor cavity. With this arrangement, when the refrigerant fluid enters the valve cavity, the third section can achieve a flow-guiding effect on the fluid, thereby reducing the noise generated when the fluid flows through the valve cavity.

[0013] Furthermore, the second section of the guide sleeve is riveted to the valve seat. The above arrangement can conveniently limit the position of the guide sleeve and ensure the stability of the guide sleeve.

[0014] Furthermore, the valve seat has a first hole segment and a second hole segment connected to each other. The first hole segment forms a mounting cavity, and the second hole segment forms a valve cavity. A riveting protrusion is annularly provided on the end surface of the valve seat near the rotor assembly. The riveting protrusion is annularly arranged around the periphery of the first hole segment and is configured to cooperate with the end surface of the second segment to secure the guide sleeve to the valve seat. This arrangement prevents the riveting protrusion from obstructing the guide sleeve from entering the mounting cavity, while facilitating the riveting of the second segment of the guide sleeve to the valve seat, thereby facilitating the assembly and processing of the electronic expansion valve.

[0015] Furthermore, the installation cavity and the valve cavity are arranged in a stepped shape, and the inner diameter of the installation cavity is larger than the inner diameter of the valve cavity. Through the above arrangement, the guide sleeve can be easily limited, ensuring the stable operation of the electronic expansion valve.

[0016] Furthermore, the electronic expansion valve further includes a gland mounted on the guide sleeve, the gland being used to limit the axial position of the guide sleeve. The gland is provided with a flow port, the flow port being correspondingly arranged with the flow channel, the flow channel being connected to the interior of the housing through the flow port, and the flow area of ​​the flow channel being less than or equal to the flow area of ​​the flow port. This arrangement ensures stable installation of the guide sleeve while maintaining effective flow through the flow channel.

[0017] Furthermore, the shape of the flow opening is circular, or the shape of the flow opening is adapted to the cross-sectional shape of the flow channel in the radial direction. This configuration facilitates the stamping process of the flow opening on the gland, reducing processing costs. By configuring the shape of the flow opening to be adapted to the cross-sectional shape of the flow channel in the radial direction, the throttling effect of the flow opening can be minimized, allowing bubbles in the fluid to pass through the flow opening more smoothly.

[0018] Furthermore, the flow area of ​​the flow port is S1, the flow area of ​​the flow channel is S2, and S2≤S1≤1.5*S2. Through the above arrangement, the noise generated when the fluid flows through the electronic expansion valve can be reduced while ensuring the overall rigidity of the gland, thereby improving the user experience.

[0019] Furthermore, multiple flow channels and flow openings are provided, and the multiple flow channels are symmetrically arranged along the axis of the guide sleeve, and the flow channels and flow openings are arranged one-to-one. This arrangement can ensure that the force exerted on the mounting sleeve when impacted by the fluid is relatively balanced, thereby reducing the disturbance exerted on the nut sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0021] FIG1 shows a schematic structural diagram of an electronic expansion valve when a section structure is provided on a guide sleeve provided in one or more embodiments of the present application;

[0022] FIG2 shows a partial enlarged view of point A in FIG1 ;

[0023] FIG3 shows a top view of a guide sleeve provided with a section structure according to one or more embodiments of the present application;

[0024] FIG4 shows a top view of the guide sleeve and the valve seat provided in one or more embodiments of the present application in cooperation with each other;

[0025] FIG5 is a schematic structural diagram of a guide sleeve provided by one or more embodiments of the present application;

[0026] FIG6 shows a schematic structural diagram of a valve needle assembly provided by one or more embodiments of the present application;

[0027] FIG7 shows a schematic structural diagram of a valve seat provided by one or more embodiments of the present application;

[0028] FIG8 is a schematic structural diagram of an electronic expansion valve when a flow hole is provided on the guide sleeve according to one or more embodiments of the present application;

[0029] FIG9 shows a top view of a guide sleeve provided with flow holes according to one or more embodiments of the present application;

[0030] FIG10 is a schematic structural diagram of an electronic expansion valve when a gland and a guide sleeve are engaged with each other according to one or more embodiments of the present application;

[0031] FIG11 shows a top view of a gland provided by one or more embodiments of the present application.

[0032] The above drawings include the following reference numerals:

[0033] 10. Housing;

[0034] 20. Valve seat; 21. Valve cavity; 22. Riveted protrusion; 23. Mounting cavity; 24. First hole section; 25. Second hole section; 201. Valve port;

[0035] 30. Rotor assembly; 31. Magnetic rotor; 32. Rotor connecting plate;

[0036] 40. Valve needle assembly; 41. First threaded section; 42. First guide section;

[0037] 50. Guide sleeve; 51. First section; 52. Second section; 521. Flow hole; 53. Third section; 54. Second threaded section; 55. Second guide section;

[0038] 60. Gland; 61. Flow port;

[0039] 100. Cross-sectional structure; 200. Circulation channel. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0041] As shown in Figures 1 to 4, an embodiment of the present application provides an electronic expansion valve, comprising a housing 10, a valve seat 20, a rotor assembly 30, a valve needle assembly 40, a guide sleeve 50, and a flow passage 200. The housing 10 has a mounting space. The valve seat 20 has a mounting cavity 23 and a valve cavity 21 that communicate with each other. The mounting cavity 23 and the valve cavity 21 are arranged in a stepped manner. The valve cavity 21 is provided with a valve port 201, which is located at the end of the valve cavity 21 away from the mounting cavity 23. The rotor assembly 30 is disposed within the housing 10 and includes a magnetic rotor 31 and a rotor connecting plate 32. The magnetic rotor 31 is sleeved around the outer side of the rotor connecting plate 32 and has a rotor cavity. The valve needle assembly 40 is disposed within the housing 10 and is connected to the rotor connecting plate 32. The valve needle assembly 40 is positioned corresponding to the valve port 201 and can adjust the flow rate at the valve port 201 when driven by the rotor assembly 30. The valve needle assembly 40 is arranged through the guide sleeve 50. The guide sleeve 50 has a first section 51 and a second section 52 connected in sequence along the axial direction. The first section 51 is partially located in the housing 10. The circulation channel 200 is arranged between the second section 52 and / or the installation cavity 23. One end of the circulation channel 200 is connected to the valve cavity 21, and the other end of the circulation channel 200 is connected to the rotor cavity. When the electronic expansion valve is in the fully closed state, the distance between the side of the rotor connecting plate 32 close to the valve cavity 21 and the end of the circulation channel 200 close to the rotor cavity is H. Wherein, A is the flow area of ​​the flow channel 200 , c is the air propagation velocity, L is the axial length of the second section 52 , D1 is the diameter of the rotor cavity, and D2 is the diameter of the first section 51 .

[0042] Applying the technical solution of the present application, the electronic expansion valve includes a housing 10, a valve seat 20, a rotor assembly 30, a valve needle assembly 40 and a guide sleeve 50. By setting a flow channel 200 to connect the valve cavity 21 and the rotor cavity, it can ensure that the pressure in the valve cavity 21 and the rotor cavity is consistent, prevent the pressure difference between the valve cavity 21 and the rotor cavity, and facilitate the rotor assembly to drive the valve needle assembly 40 to rotate. However, this will cause the valve cavity 21 and the rotor cavity to resonate when the fluid flows through the electronic expansion valve, thereby causing the fluid to generate a large noise when flowing through the electronic expansion valve. According to the Helmholtz resonance principle, the resonance frequency Where V is the volume of the rotor cavity, V = π × (D1 2 / 4-D2 2 / 4)×H, H is the distance between the side of the rotor connecting plate 32 close to the valve cavity 21 and the side of the valve seat 20 close to the rotor cavity when the electronic expansion valve is in the fully closed state, A is the flow area of ​​the flow channel 200, c is the air propagation speed, and the minimum frequency of sound that the human ear can sensitively perceive is 1000Hz. By setting the resonant frequency f≤1000Hz, we can get By the above arrangement, when the electronic expansion valve is in the fully closed state, the distance between the side of the rotor connecting plate 32 close to the valve cavity 21 and the side of the flow channel 200 close to the rotor cavity satisfies This can reduce the resonance frequency of the rotor cavity and the valve cavity 21 to a level that the human ear can sensitively feel, thereby reducing the noise generated when the fluid flows through the electronic expansion valve, ensuring the noise reduction effect, and improving the user experience comfort.

[0043] As shown in Figures 1 to 5, the side wall of the second section 52 has a cross-sectional structure 100, and a circulation channel 200 is formed between the cross-sectional structure 100 and the inner wall of the installation cavity 23. Through the above arrangement, when the fluid flows through the valve cavity 21, it can enter the rotor cavity through the circulation channel 200, ensuring the pressure balance in the valve cavity 21 and the rotor cavity, reducing the pressure difference that needs to be overcome when the valve needle assembly 40 opens or blocks the valve port 201, and facilitating the electronic expansion valve to quickly adjust the flow rate. At the same time, it can also reduce the pressure fluctuations generated when the fluid flows through the valve cavity 21, further reduce the noise generated when the fluid flows through the electronic expansion valve, and improve the user comfort experience. Among them, when the circulation channel 200 is formed between the cross-sectional structure 100 and the inner wall of the installation cavity 23, D3 is the diameter of the mounting cavity 23 minus the distance between the side wall of the second section 52 and the inner wall of the mounting cavity 23 , and D4 is the diameter of the second section 52 .

[0044] Furthermore, the sidewall of the second section 52 has a plurality of section structures 100, and the plurality of section structures 100 are symmetrically arranged along the axis of the guide sleeve 50. Through the above arrangement, when the fluid enters the rotor cavity from the valve cavity 21 along the circulation channel 200, the plurality of section structures 100 are symmetrically arranged along the axis of the guide sleeve 50, which can ensure that the force exerted on the guide sleeve 50 when impacted by the fluid is relatively balanced, reduce the disturbance exerted on the guide sleeve 50, and ensure the accuracy of the opening of the electronic expansion valve control valve port 201. In a specific embodiment of the present application, two section structures 100 are provided, and the two section structures 100 are symmetrically arranged along the axis of the guide sleeve 50. Correspondingly, there are also two circulation channels 200. Through the above arrangement, the two circulation channels 200 can reduce the noise generated when the fluid flows through the electronic expansion valve while ensuring the stability of the guide sleeve 50 in the installation cavity 23, thereby improving the noise reduction effect of the electronic expansion valve.

[0045] 8 and 9 , in some other embodiments of the present application, a through flow hole 521 is provided on the second section 52, and the flow hole 521 forms a flow channel 200. Similar to the section structure 100, a plurality of flow holes 521 can also be provided, and the plurality of flow holes 521 are symmetrically arranged along the axis of the guide sleeve 50. When the flow hole 521 forms the flow channel 200, it is necessary to meet Wherein, A is the cross-sectional area of ​​the flow hole 521 perpendicular to the extension direction.

[0046] In other embodiments of the present application, a circulation groove structure is also provided between the installation cavity 23 and the side wall of the second section 52 , and the installation cavity 23 and the side wall of the second section 52 cooperate to form a circulation channel 200 .

[0047] As shown in Figures 5 and 6, in the present application, the valve needle assembly 40 comprises a first threaded segment 41 and a first guide segment 42 connected in sequence. The first guide segment 42 is disposed proximate to the valve port 201. The guide sleeve 50 comprises a second threaded segment 54 and a second guide segment 55 connected in sequence. The first threaded segment 41 and the second threaded segment 54 are threadedly engaged. The valve needle assembly 40 rotates relative to the guide sleeve 50 to approach or move away from the valve port 201, and the first guide segment 42 and the second guide segment 55 are guided and engaged. Through the above arrangement, the first threaded segment 41 can rotate relative to the second threaded segment 54 under the drive of the rotor assembly 30. The threaded engagement of the first threaded segment 41 and the second threaded segment 54 enables the valve needle assembly 40 to move upward or downward toward or away from the valve port 201, thereby closing or opening the valve port 201. Furthermore, the guided engagement of the first guide segment 42 and the second guide segment 55 ensures the precise engagement of the valve needle assembly 40 with the valve port 201, thereby improving the performance of the electronic expansion valve.

[0048] Furthermore, the guide sleeve 50 includes a third section 53, which is connected to the second section 52 and is located in the valve cavity 21. The outer diameter of the third section 53 is smaller than the outer diameter of the second section 52. This arrangement can reduce the space occupied by the guide sleeve 50 in the valve cavity 21 and reduce the impact of the guide sleeve 50 on fluid circulation.

[0049] Furthermore, the mounting cavity 23 and the valve cavity 21 are arranged in a stepped configuration, with the inner diameter of the mounting cavity 23 being larger than the inner diameter of the valve cavity 21. This configuration forms a stepped surface between the second section 52 and the third section 53. The stepped surface can cooperate with the mounting cavity 23 to limit the position, thereby achieving axial limitation of the guide sleeve 50 within the mounting cavity 23, preventing the guide sleeve 50 from moving toward the valve cavity 21 under the drive of the valve needle assembly 40, thereby ensuring the stability of the electronic expansion valve.

[0050] Furthermore, the diameter of the third section 53 at the end closest to the valve port 201 gradually decreases as it moves away from the rotor cavity. Because bubbles tend to burst when passing through the valve port 201, this arrangement allows the third section 53 to guide the bubbles in the refrigerant fluid as it enters the valve cavity 21, allowing them to more smoothly enter the circulation channel 200. This reduces the number of bubbles passing through the valve port 201 and, consequently, reduces the noise generated by the fluid flowing through the valve cavity 21.

[0051] In the present application, the first section 51, the second section 52, and the third section 53 are an integrally molded structure; alternatively, the second section 52 is a metal part, and the guide sleeve 50 is injection molded with the second section 52 as an insert. Through the above arrangement, the overall structural stability of the guide sleeve 50 can be improved, and the guide sleeve 50 can be prevented from loosening under the impact of the fluid. At the same time, the integral molding manufacturing process can also facilitate the production and processing of the guide sleeve 50. In a specific embodiment of the present application, the guide sleeve 50 is injection molded with the second section 52 as a metal base, and the injection molding material is made of engineering plastic material. Engineering plastic has good heat resistance, cold resistance, machinability and structural stability, which facilitates the processing and molding of the guide sleeve 50.

[0052] Furthermore, the second section 52 of the guide sleeve 50 is interference-fitted within the mounting cavity 23. This arrangement reduces the possible gap between the outer wall of the second section 52 and the inner wall of the mounting cavity 23, reduces the amplitude of shaking of the guide sleeve 50 caused by fluid impact, and ensures the stability of the guide sleeve 50 during operation of the electronic expansion valve.

[0053] In a specific embodiment of the present application, the second section 52 of the guide sleeve 50 is riveted to the valve seat 20. Through the above arrangement, the position of the guide sleeve 50 can be easily limited, thereby ensuring the stability of the guide sleeve 50.

[0054] As shown in FIG7 , the valve seat 20 has a first hole section 24 and a second hole section 25 connected to each other. The first hole section 24 forms a mounting cavity 23, and the second hole section 25 forms a valve cavity 21. A rivet protrusion 22 is annularly provided on the end surface of the valve seat 20 near the rotor assembly 30. The rivet protrusion 22 is annularly provided on the periphery of the first hole section 24. The rivet protrusion 22 is used to cooperate with the end surface of the second section 52 to fix the guide sleeve 50 to the valve seat 20. Through this arrangement, during the installation of the guide sleeve 50, the rivet protrusion 22 will not block the guide sleeve 50 from entering the mounting cavity 23. After the second section of the guide sleeve 50 is interference-fitted into the first hole section 24, the rivet protrusion 22 can be bent, thereby achieving riveting of the second section 52 of the guide sleeve 50 to the valve seat 20. The above method has a simple structure and is easy to process, facilitating the assembly and processing of the electronic expansion valve.

[0055] As shown in Figures 10 and 11, the electronic expansion valve also includes a gland 60, which is sleeved on the guide sleeve 50. The gland 60 is used to limit the axial position of the guide sleeve 50. A circulation port 61 is provided on the gland 60. The circulation port 61 is corresponding to the circulation channel 200. The circulation channel 200 is connected to the interior of the housing 10 through the circulation port 61. The circulation area of ​​the circulation channel 200 is less than or equal to the circulation area of ​​the circulation port 61. Through the above arrangement, the gland 60 can ensure the stability of the guide sleeve 50 fixed in the housing 10, prevent the guide sleeve 50 from axial movement, and ensure the stable operation of the electronic expansion valve. At the same time, by providing the circulation port 61, the communication between the circulation channel 200 and the rotor cavity can also be ensured, reducing the noise generated during the operation of the electronic expansion valve and improving the user experience.

[0056] Furthermore, the shape of the flow opening 61 is circular, or the shape of the flow opening 61 is adapted to the radial cross-sectional shape of the flow channel 200. By setting the shape of the flow opening 61 to be circular, the stamping process of the flow opening 61 on the gland 60 can be facilitated, reducing the processing cost; by setting the shape of the flow opening 61 to be adapted to the radial cross-sectional shape of the flow channel 200, the throttling effect of the flow opening 61 can be minimized, allowing bubbles in the fluid to pass through the flow opening 61 more smoothly.

[0057] Specifically, the flow area of ​​the flow port 61 is S1, and the flow area of ​​the flow channel 200 is S2, where S2≤S1≤1.5*S2. When S1<S2, the flow port 61 will perform secondary throttling on the bubbles in the fluid, and the fluid will generate a large noise when flowing through the electronic expansion valve; when S1>1.5*S2, the opening is too large, which will affect the overall rigidity of the gland 60 and reduce the limiting effect of the gland 60. Therefore, in the present application, by setting S2≤S1≤1.5*S2, the noise generated by the fluid when flowing through the electronic expansion valve can be reduced while ensuring the overall rigidity of the gland 60, thereby improving the user experience.

[0058] Specifically, multiple flow channels 200 and flow ports 61 are provided. The multiple flow channels 200 are symmetrically arranged along the axis of the guide sleeve 50, and the flow channels 200 and flow ports 61 are arranged one-to-one. This arrangement ensures that when fluid enters the rotor cavity from the valve cavity 21 along the flow channels 200, the force exerted on the guide sleeve 50 by the fluid is relatively balanced, reducing the disturbance to the guide sleeve 50 and ensuring the accuracy of the opening of the valve port 201 controlled by the electronic expansion valve.

[0059] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should 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.

[0060] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to actual proportional relationships. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0061] In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0062] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0063] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0064] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. An electronic expansion valve, characterized in that: The electronic expansion valve comprises: A housing (10) having an installation space; A valve seat (20), the valve seat (20) having a mounting cavity (23) and a valve cavity (21) that are connected to each other, and a valve port (201) is provided on the valve seat (20); A rotor assembly (30) is arranged in the housing (10), the rotor assembly (30) comprising a magnetic rotor (31) and a rotor connecting plate (32), the magnetic rotor (31) is sleeved on the outer side of the rotor connecting plate (32), and the magnetic rotor (31) has a rotor cavity; A valve needle assembly (40) is arranged in the housing (10), the valve needle assembly (40) is connected to the rotor connecting plate (32), the valve needle assembly (40) is arranged corresponding to the valve port (201), and the valve needle assembly (40) can adjust the flow at the valve port (201) under the drive of the rotor assembly (30); a guide sleeve (50), wherein the valve needle assembly (40) passes through the guide sleeve (50), and the guide sleeve (50) comprises a first section (51) and a second section (52) which are connected in sequence along the axial direction, wherein a portion of the first section (51) is located in the housing (10), and the second section (52) is arranged in the mounting cavity (23); A circulation channel (200) is arranged between the second section (52) and / or the installation cavity (23); one end of the circulation channel (200) is in communication with the valve cavity (21); the other end of the circulation channel (200) is in communication with the rotor cavity; when the electronic expansion valve is in a fully closed state, a distance H is between a side of the rotor connecting plate (32) close to the valve cavity (21) and an end of the circulation channel (200) close to the rotor cavity; Wherein, A is the flow area of ​​the flow channel (200), c is the air propagation velocity, L is the axial length of the second section (52), D1 is the diameter of the rotor cavity, and D2 is the diameter of the first section (51).

2. The electronic expansion valve according to claim 1, characterized in that: The side wall of the second section (52) has a section structure (100), and the flow channel (200) is formed between the section structure (100) and the inner wall of the installation cavity (23).

3. The electronic expansion valve according to claim 1, characterized in that: The second section (52) is provided with a circulation hole (521), and the circulation hole (521) forms the circulation channel (200).

4. The electronic expansion valve according to claim 1, characterized in that: The valve needle assembly (40) comprises a first threaded section (41) and a first guide section (42) connected in sequence, the first guide section (42) being arranged close to the valve port (201), the guide sleeve (50) comprises a second threaded section (54) and a second guide section (55) connected in sequence, the first threaded section (41) and the second threaded section (54) being threadedly matched, the valve needle assembly (40) being rotated relative to the guide sleeve (50) to approach or move away from the valve port (201), the first guide section (42) and the second guide section (55) being guidedly matched.

5. The electronic expansion valve according to claim 1, characterized in that: The guide sleeve (50) further comprises a third section (53), the third section (53) being connected to the second section (52), and the third section (53) being located in the valve cavity (21), and the outer diameter of the third section (53) being smaller than the outer diameter of the second section (52).

6. The electronic expansion valve according to claim 5, characterized in that: The diameter of the end of the third section (53) close to the valve port (201) gradually decreases in a direction away from the rotor chamber.

7. The electronic expansion valve according to claim 1, characterized in that: The second section (52) of the guide sleeve (50) is riveted to the valve seat (20).

8. The electronic expansion valve according to claim 7, characterized in that: The valve seat (20) has a first hole section (24) and a second hole section (25) which are connected to each other, the first hole section (24) forms the installation cavity (23), and the second hole section (25) forms the valve cavity (21). A riveted protrusion (22) is arranged on the end face of the valve seat (20) close to the rotor assembly (30), and the riveted protrusion (22) is arranged on the periphery of the first hole section (24). The riveted protrusion is used to cooperate with the end face of the second section (52) to fix the guide sleeve (50) on the valve seat (20).

9. The electronic expansion valve according to claim 1, characterized in that: The installation cavity (23) and the valve cavity (21) are arranged in a stepped manner, and the inner diameter of the installation cavity (23) is larger than the inner diameter of the valve cavity (21).

10. The electronic expansion valve according to claim 1, characterized in that: The electronic expansion valve further comprises: A pressure cover (60) is sleeved on the guide sleeve (50), and the pressure cover (60) is used to limit the axial position of the guide sleeve (50). A flow port (61) is provided on the pressure cover (60), and the flow port (61) is correspondingly provided to the flow channel (200). The flow channel (200) is connected to the interior of the shell (10) through the flow port (61), and the flow area of ​​the flow channel (200) is less than or equal to the flow area of ​​the flow port (61).

11. The electronic expansion valve according to claim 10, characterized in that: The shape of the circulation opening (61) is circular, or the shape of the circulation opening (61) is adapted to the cross-sectional shape of the circulation channel (200) in the radial direction.

12. The electronic expansion valve according to claim 10, characterized in that: The flow area of ​​the flow port (61) is S1, the flow area of ​​the flow channel (200) is S2, and S2≤S1≤1.5*S2.

13. The electronic expansion valve according to claim 10, characterized in that: A plurality of the circulation channels (200) and the circulation ports (61) are provided, and the plurality of circulation channels (200) are symmetrically arranged along the axis of the guide sleeve (50), and the circulation channels (200) and the circulation ports (61) are arranged in a one-to-one correspondence.

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