Electronic expansion valve

Abstract

The electronic expansion valve comprises a stop seat, a rotor assembly, a lead screw, a valve element assembly and a valve seat assembly, and the valve seat assembly is provided with a valve port part. The valve element assembly comprises a sliding nut and a valve needle assembly, the end, away from the rotor assembly, of the lead screw is in threaded fit with the sliding nut, and the sliding nut is matched with the stop seat through a limiting structure so that the lead screw can drive the sliding nut to drive the valve element assembly to move in the axial direction of the lead screw relative to the stop seat to open or close the valve port part. The limiting structure can prevent the sliding nut from rotating around the axis of the lead screw relative to the stop base. According to the electronic expansion valve, the problem that abrasion between the valve element and the valve seat is large is solved.

Description

Technical Field

[0001] The present application relates to the field of valve body technology, and in particular to an electronic expansion valve. Background Art

[0002] In the existing electronic expansion valve, the rotor is driven to move by the coil, and the rotor is fixedly connected to the screw rod. When the rotor rotates, it also drives the screw rod to move up and down along the axial direction of the valve. When the rotor is far away from the coil, the coil still needs to provide sufficient driving force, so the volume of the coil needs to be large enough. The larger volume of the coil increases the overall volume of the valve and increases the manufacturing cost.

[0003] How to reduce the overall volume of the valve is the main technical problem to be solved by this application. Summary of the invention

[0004] Based on this, it is necessary to provide an electronic expansion valve to solve the problem of large wear between the existing valve core and the valve seat.

[0005] The electronic expansion valve provided in the present application includes a stop seat, a rotor assembly, a screw rod, a valve core assembly and a valve seat assembly, wherein the valve seat assembly is provided with a valve port. The valve core assembly includes a sliding nut and a valve needle assembly, wherein one end of the screw rod away from the rotor assembly is threadedly matched with the sliding nut, and the sliding nut and the stop seat are matched with each other through a limiting structure, so that the screw rod can drive the sliding nut to drive the valve core assembly to move relative to the stop seat along the axial direction of the screw rod to open or close the valve port, and the limiting structure can prevent the sliding nut from rotating relative to the stop seat around the axis of the screw rod.

[0006] In one of the embodiments, a stop protrusion extending along the radial direction of the sliding nut is provided on the circumferential side thereof, and a guide groove extending along the axial direction of the stop seat is provided corresponding to the stop protrusion. The end of the stop protrusion away from the sliding nut extends into the guide groove and can be slidably matched with the guide groove along the axial direction of the stop seat, so that the sliding nut and the stop seat can be slidably matched along the axial direction of the stop seat, and the stop protrusion and the guide groove constitute a limiting structure.

[0007] In one embodiment, there are multiple anti-rotation protrusions, and the multiple anti-rotation protrusions are evenly distributed along the circumference of the sliding nut.

[0008] In one of the embodiments, the number of the guide grooves is also multiple, and the multiple guide grooves are evenly distributed along the circumference of the stop seat, and the guide grooves and the anti-rotation protrusions are arranged in a one-to-one correspondence.

[0009] In one embodiment, the number of the anti-rotation protrusion and the number of the guide groove are both one.

[0010] In one of the embodiments, the gap between the anti-rotation protrusion and the side wall of the guide groove is less than or equal to 0.1 mm.

[0011] In one embodiment, the electronic expansion valve also includes a stop ring and a guide rod. An outer guide rail portion is provided on the outer peripheral side of the stop seat away from the screw rod. The stop ring is sleeved on the outer periphery of the stop seat and movably cooperates with the outer guide rail portion. The guide rod is fixedly connected to the rotor assembly or the screw rod so that the rotor assembly can drive the guide rod to push the stop ring to move spirally along the outer guide rail portion.

[0012] In one embodiment, the stop seat is provided with a first stop portion, and when the stop ring stops at the first stop portion, the valve core assembly and the valve port portion are spaced apart and stop moving. The stop seat is also provided with a second stop portion, and when the stop ring stops at the second stop portion, the valve core assembly abuts against the valve port portion and closes the valve port portion.

[0013] In one embodiment, the sliding nut includes a main body and a connecting part, the main body is an injection molded part, and the connecting part is a metal part. The sliding nut is threadedly connected to the screw rod through the main body, one end of the connecting part is fixedly connected to the main body, and the other end is welded to the valve needle assembly.

[0014] In one embodiment, the electronic expansion valve further comprises a shell, which is disposed on the outside of the rotor assembly, a part of the lead screw and a part of the valve core assembly and is welded to the valve seat assembly.

[0015] Compared with the prior art, by setting a limit structure, the sliding nut can be prevented from rotating relative to the stop seat around the axis of the screw rod. At this time, the sliding nut can move relative to the screw rod along the axial direction of the screw rod, so that the screw rod drives the sliding nut to drive the valve core assembly to open or close the valve port. In normal operation, the rotor assembly and the screw rod do not move in the axial direction, which can simplify the overall volume of the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic diagram of a partial structure of an electronic expansion valve according to an embodiment of the present application;

[0018] Figure 2 A cross-sectional view of an electronic expansion valve according to an embodiment of the present application;

[0019] Figure 3 A cross-sectional view of an electronic expansion valve according to another embodiment of the present application;

[0020] Figure 4A schematic diagram of the partial structure of an electronic expansion valve according to an embodiment of the present application.

[0021] : Illustration numerals: 100, rotor assembly; 200, screw rod; 300, valve core assembly; 310, sliding nut; 311, anti-rotation protrusion; 314, main body; 315, connecting portion; 320, valve needle assembly; 400, valve seat assembly; 410, valve mouth portion; 510, stop seat; 511, external threaded portion; 515, guide groove; 520, stop ring; 530, guide rod; 540, first stop portion; 550, second stop portion; 800, shell. DETAILED DESCRIPTION

[0022] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0024] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0025] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0026] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0028] See also Figure 1-Figure 4 In one embodiment, the electronic expansion valve includes a stop seat 510, a rotor assembly 100, a screw rod 200, a valve core assembly 300 and a valve seat assembly 400. The stop seat 510 is fixedly connected to the valve seat assembly 400, and the stop seat 510 is arranged on the outer periphery of the screw rod 200. The valve seat assembly 400 is provided with a valve mouth portion 410. The valve core assembly 300 can move axially relative to the valve seat assembly 400 along the screw rod 200. One end of the screw rod 200 is fixedly connected to the rotor assembly 100, and the other end is connected to the valve core assembly 300. The rotor assembly 100 can drive the valve core assembly 300 to move toward or away from the valve mouth portion 410 through the screw rod 200.

[0029] Specifically, the electronic expansion valve further includes a stop ring 520 and a guide rod 530. The outer peripheral side of the stop seat 510 away from the screw rod 200 is also provided with an outer guide rail portion. The stop ring 520 is sleeved on the outer periphery of the stop seat 510 and movably cooperates with the outer guide rail portion. Specifically, the outer guide rail portion can be an outer threaded portion 511 arranged on the outer peripheral side of the stop seat 510 away from the screw rod 200. The stop ring 520 is sleeved on the outer periphery of the stop seat 510 and movably cooperates with the outer threaded portion 511. The outer guide rail portion can also be a spiral spring (not shown) spirally wound on the outer side of the stop seat 510. The stop ring 520 spirally moves along the extension direction of the spiral spring. The guide rod 530 is fixedly connected to the rotor assembly 100 or the screw rod 200, so that the rotor assembly 100 can drive the guide rod 530 to push the stop ring 520 to spirally move along the outer guide rail portion. In addition, the screw rod 200 and the valve core assembly 300 are movably threadedly connected.

[0030] The valve core assembly 300 includes a sliding nut 310 and a valve needle assembly 320. The end of the screw rod 200 away from the rotor assembly 100 is threadedly matched with the sliding nut 310. The sliding nut 310 and the stop seat 510 are matched through a limiting structure, so that the screw rod 200 can drive the sliding nut 310 to drive the valve core assembly 300 to move axially relative to the stop seat 510 along the screw rod 200 to open or close the valve mouth 410, and the limiting structure can prevent the sliding nut 310 from rotating around the axis of the screw rod 200 relative to the stop seat 510.

[0031] Specifically, it should be noted that the upper part (the part close to the rotor assembly 100) and the lower part (the part used to cooperate with the sliding nut 310) of the stop seat 510 can be an integrally formed setting or a split design, but no matter which form, the stop seat 510 is fixedly connected to the valve seat assembly (400). By setting a limiting structure, the sliding nut 310 can be prevented from rotating relative to the stop seat 510 around the axis of the screw rod 200. At this time, the sliding nut 310 can move relative to the screw rod 200 along the axial direction of the screw rod 200, so that the screw rod 200 drives the sliding nut 310 to drive the valve core assembly 300 to open or close the valve port 410. The relative rotation between the sliding nut 310 and the stop seat 510 is prevented from causing the sliding nut 310 and the stop seat 510 to wear.

[0032] It should be noted that the electronic expansion valve further includes a housing 800 , which covers the outer sides of the rotor assembly 100 , a portion of the lead screw 200 and a portion of the valve core assembly 300 and is welded to the valve seat assembly 400 .

[0033] In this embodiment, the circumferential side of the sliding nut 310 is provided with a rotation-stopping protrusion 311 extending along its radial direction, and the stop seat 510 is provided with a guide groove 515 extending along its axial direction corresponding to the rotation-stopping protrusion 311, and one end of the rotation-stopping protrusion 311 away from the sliding nut 310 extends into the guide groove 515 and can slide and cooperate with the guide groove 515 along the axial direction of the stop seat 510, so that the sliding nut 310 and the stop seat 510 slide and cooperate along the axial direction of the stop seat 510. In addition, the rotation-stopping protrusion 311 and the guide groove 515 constitute a limiting structure.

[0034] Specifically, in one embodiment, there are multiple anti-rotation protrusions 311, and the multiple anti-rotation protrusions 311 are evenly distributed along the circumference of the sliding nut 310. Correspondingly, there are multiple guide grooves 515, and the multiple guide grooves 515 are evenly distributed along the circumference of the stop seat 510, and the guide grooves 515 and the anti-rotation protrusions 311 are arranged one by one.

[0035] In this way, when the side wall of the guide groove 515 restricts the rotation of the anti-rotation protrusion 311 , the circumferential force of the sliding nut 310 can be uniform, preventing the sliding nut 310 from deflecting due to uneven force at different locations and affecting the axial displacement of the sliding nut 310 .

[0036] More specifically, the number of the anti-rotation protrusions 311 and the guide grooves 515 can be two, three, or four, etc., which are not listed here one by one.

[0037] But it is not limited to this. In other embodiments, the number of the anti-rotation protrusion 311 can also be one, which greatly simplifies the structure of the electronic expansion valve.

[0038] In one embodiment, the gap between the anti-rotation protrusion 311 and the side wall of the guide groove 515 is less than or equal to 0.1 mm.

[0039] It should be noted that each guide groove 515 has two side walls that are arranged opposite to each other, and the gap between the anti-rotation protrusion 311 and any side wall is less than or equal to 0.1 mm.

[0040] With such arrangement, when the anti-rotation protrusion 311 changes its rotation direction, the amplitude of the collision with the side wall of the guide groove 515 is reduced, thereby reducing the wear of the anti-rotation protrusion 311 and the side wall of the guide groove 515, thereby increasing the service life of the electronic expansion valve.

[0041] In one embodiment, the stop seat 510 is provided with a first stop portion 540 , and when the stop ring 520 stops at the first stop portion 540 , the valve core assembly 300 and the valve port portion 410 are spaced apart and stop moving.

[0042] In one embodiment, the stop seat 510 is further provided with a second stop portion 550 . When the stop ring 520 stops at the second stop portion 550 , the valve core assembly 300 abuts against the valve port 410 and closes the valve port 410 .

[0043] By providing the first stopper 540 and the second stopper 550, the movement stroke of the stop ring 520 in the external threaded portion 511 can be effectively limited, thereby limiting the rotation angle range of the guide rod 530 relative to the stop seat 510. Since the guide rod 530 is fixedly connected to the rotor assembly 100 or the screw rod 200, such a configuration can effectively limit the rotation angle range of the rotor assembly 100, thereby controlling the movement stroke of the valve core assembly 300 relative to the valve port 410, and avoiding wear of the valve core assembly 300 and the valve port 410. Moreover, such a configuration can also prevent the stop ring 520 from moving to the area outside the external threaded portion 511, thereby affecting the thread fit between the stop ring 520 and the stop seat 510.

[0044] In one embodiment, the sliding nut 310 includes a main body 314 and a connecting portion 315, the main body 314 is an injection molded part, and the connecting portion 315 is a metal part. The sliding nut 310 is threadedly connected to the screw rod 200 through the main body 314, one end of the connecting portion 315 is fixedly connected to the main body 314, and the other end is welded to the valve needle assembly 320.

[0045] The main body 314 is an injection molded part, which can significantly reduce the weight of the sliding nut 310 and reduce the difficulty of processing the sliding nut 310. The connecting part 315 is a metal part, which is conducive to welding the valve needle assembly 320 through the connecting part 315 of the sliding nut 310, thereby improving the connection strength between the sliding nut 310 and the valve needle assembly 320. In addition, with such a configuration, the same sliding nut 310 can be matched with valve needle assemblies 320 of different specifications, that is, only one sliding nut 310 needs to be made to adapt to valve needle assemblies 320 of different specifications.

[0046] Specifically, the connection portion 315 can be made of copper, stainless steel, aluminum or other alloy materials, which are not listed here one by one.

[0047] In one embodiment, the connecting portion 315 is embedded in the main body 314 .

[0048] Specifically, the connection portion 315 is embedded in the main body portion 314 through an integral injection molding process, thereby further reducing the difficulty of assembling the connection portion 315 and the main body portion 314 and improving the connection strength between the connection portion 315 and the main body portion 314 .

[0049] However, the present invention is not limited thereto. In other embodiments, the connection portion 315 may be connected to the main body portion 314 by snapping, bonding, welding or threading.

[0050] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the scope of patent protection of the present application shall be subject to the attached claims.

Claims

1. An electronic expansion valve, characterized in that: It comprises a stop seat (510), a rotor assembly (100), a screw rod (200), a valve core assembly (300) and a valve seat assembly (400), wherein the valve seat assembly (400) is provided with a valve port portion (410); The valve core assembly (300) includes a sliding nut (310) and a valve needle assembly (320), and one end of the screw rod (200) away from the rotor assembly (100) is threadedly matched with the sliding nut (310), and the sliding nut (310) and the stop seat (510) are matched with each other through a limiting structure, so that the screw rod (200) can drive the sliding nut (310) to drive the valve core assembly (300) to move axially along the screw rod (200) relative to the stop seat (510) to open or close the valve mouth (410), and the limiting structure can prevent the sliding nut (310) from rotating relative to the stop seat (510) around the axis of the screw rod (200).

2. The electronic expansion valve according to claim 1, characterized in that: The circumferential side of the sliding nut (310) is provided with a stop protrusion (311) extending along its radial direction, and the stop seat (510) is provided with a guide groove (515) extending along its axial direction corresponding to the stop protrusion (311), and one end of the stop protrusion (311) away from the sliding nut (310) extends into the guide groove (515) and can slide with the guide groove (515) along the axial direction of the stop seat (510), so that the sliding nut (310) and the stop seat (510) can slide along the axial direction of the stop seat (510), and the stop protrusion (311) and the guide groove (515) constitute the limiting structure.

3. The electronic expansion valve according to claim 2, characterized in that: The number of the anti-rotation protrusions (311) is multiple, and the multiple anti-rotation protrusions (311) are evenly distributed along the circumference of the sliding nut (310).

4. The electronic expansion valve according to claim 3, characterized in that: The number of the guide grooves (515) is also multiple, and the multiple guide grooves (515) are evenly distributed along the circumference of the stop seat (510), and the guide grooves (515) and the anti-rotation protrusions (311) are arranged in a one-to-one correspondence.

5. The electronic expansion valve according to claim 2, characterized in that: The number of the anti-rotation protrusion (311) and the number of the guide groove (515) are both one.

6. The electronic expansion valve according to claim 2, characterized in that: The gap between the anti-rotation protrusion (311) and the side wall of the guide groove (515) is less than or equal to 0.1 mm.

7. The electronic expansion valve according to claim 1, characterized in that: It also includes a stop ring (520) and a guide rod (530); an outer guide rail portion is provided on the outer peripheral side of the stop seat (510) away from the screw rod (200); the stop ring (520) is sleeved on the outer periphery of the stop seat (510) and movably cooperates with the outer guide rail portion; the guide rod (530) is fixedly connected to the rotor assembly (100) or the screw rod (200) so that the rotor assembly (100) can drive the guide rod (530) to push the stop ring (520) to move spirally along the outer guide rail portion.

8. The electronic expansion valve according to claim 7, characterized in that: The stop seat (510) is provided with a first stop portion (540), and when the stop ring (520) stops at the first stop portion (540), the valve core assembly (300) and the valve port portion (410) are spaced apart and stop moving; The stop seat (510) is also provided with a second stop portion (550). When the stop ring (520) stops at the second stop portion (550), the valve core assembly (300) abuts against the valve mouth portion (410) and closes the valve mouth portion (410).

9. The electronic expansion valve according to claim 1, characterized in that: The sliding nut (310) comprises a main body (314) and a connecting part (315), wherein the main body (314) is an injection molded part, and the connecting part (315) is a metal part. The sliding nut (310) is threadedly connected to the screw rod (200) through the main body (314), and one end of the connecting part (315) is fixedly connected to the main body (314), and the other end is welded to the valve needle assembly (320).

10. The electronic expansion valve according to claim 1, characterized in that: It also comprises a housing (800), wherein the housing (800) is arranged on the outside of the rotor assembly (100), part of the screw rod (200) and part of the valve core assembly (300), and is welded to the valve seat assembly (400).

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