Electronic expansion valve

Abstract

The electronic expansion valve comprises a shell, a valve element, a valve seat and a transmission assembly and further comprises a valve cavity, the shell is fixed to the valve seat, the transmission assembly is fixed or connected with the valve element so as to drive the valve element to be close to or away from the valve seat, the valve seat is provided with a valve port channel, the valve port channel can be communicated with the valve cavity, and the valve cavity is communicated with the valve element. The valve seat comprises a body part and an extension part, the extension part is connected with the body part, and the extension part extends towards the valve element in the axial direction; the valve element is sleeved with the extending part, and the valve element can move in the axial direction along the extending part so that the valve port channel can communicate with the valve cavity or the valve port channel can be prevented from communicating with the valve cavity. Therefore, due to the fact that the valve element is sleeved with the extending part, the extending part plays a role in limiting the valve element, the offset caused by impact on the valve element can be reduced, and the gap generated when the valve element closes the valve port channel due to the offset of the valve element is reduced.

Description

Technical Field

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

[0002] In the related art, the electronic expansion valve includes a valve core and a valve seat, the valve seat is provided with a valve mouth portion, and the valve core is used to close or open the valve mouth portion; in the process of the valve core moving up and down to approach or move away from the valve mouth portion, the fluid coming in from the side will impact the valve core, causing the valve core to shift, so that the valve core has a gap when closing the valve mouth portion, thereby causing internal leakage. Summary of the invention

[0003] In order to solve the above technical problems, the following technical solutions are provided:

[0004] An electronic expansion valve comprises a shell, a valve core, a valve seat and a transmission assembly, and also comprises a valve cavity, wherein the shell is fixed to the valve seat, the transmission assembly is fixed to or connected to the valve core to drive the valve core to approach or move away from the valve seat, the valve seat has a valve port channel, and the valve port channel can be communicated with the valve cavity, the valve seat comprises a main body and an extension portion, the extension portion is connected to the main body, and the extension portion extends toward the valve core in an axial direction; the extension portion is sleeved on the valve core, and the valve core can move in an axial direction along the extension portion to connect the valve port channel and the valve cavity or block the valve port channel from being communicated with the valve cavity.

[0005] In this way, since the extension part is sleeved on the valve core, and the valve core can move in the axial direction along the extension part to connect the valve port channel and the valve cavity or block the valve port channel from being connected with the valve cavity, the extension part plays a role of limiting the valve core, which is beneficial to reducing the displacement of the valve core caused by the impact, thereby reducing the gap caused by the displacement of the valve core when the valve core closes the valve port channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is a schematic diagram of a valve core located in a first position in an embodiment of the present application;

[0007] Figure 2 for Figure 1 A magnified schematic diagram of the middle area A;

[0008] Figure 3 This is a schematic diagram of a valve core being located in a second position in an embodiment of the present application;

[0009] Figure 4 for Figure 1 A three-dimensional schematic diagram of the middle valve core;

[0010] Figure 5 for Figure 4 A schematic cross-sectional view of the middle valve core;

[0011] Figure 6 for Figure 1 A schematic diagram of the flow holes of the middle valve core unfolded along the circumferential direction;

[0012] Figure 7 A schematic diagram of the flow hole of the valve core in the second embodiment unfolded along the circumferential direction;

[0013] Figure 8 A schematic diagram of the flow hole of the valve core in the third embodiment unfolded along the circumferential direction;

[0014] Fig. 9 is a schematic diagram of a valve seat in a fourth embodiment;

[0015] Fig.10 Schematic diagram of the valve seat in the fifth embodiment.

[0016] Reference numerals:

[0017] 1. Valve core; 2. Valve seat; 3. Valve chamber; 4. Sealing pad; 5. Screw rod; 6. Limiting piece; 7. Elastic piece; 8. Guide sleeve; 9. Sealing piece; 100. Rotor; 200. Nut; 300. Housing; 400. Transmission assembly;

[0018] 12, flow hole; 121, first flow section; 122, second flow section; 123, third flow section; 13, abutment end; 131, tip; 14, abutment surface;

[0019] 20, valve port channel; 201, first through section; 202, first step portion; 203, second through section; 21, body portion; 22, extension portion; 23, second step portion; 24, guide portion;

[0020] 51. Main body; 52. Second flange; 81. Guide channel; 301. First part; 302. Second part. DETAILED DESCRIPTION

[0021] The technical solution of the specific implementation mode is described below with reference to the accompanying drawings.

[0022] like Figure 1-6 As shown,

[0023] An electronic expansion valve includes a housing 300, a valve core 1, a valve seat 2, a transmission assembly 400, and a valve chamber 3. The housing 300 is fixed to the valve seat 2, specifically by welding; in this embodiment, the housing 300 is divided into two parts, the housing 300 includes a first part 301 and a second part 302, the first part 301 and the valve seat 2 are respectively located at two ends of the second part 302, and the first part 301 and the valve seat 2 are respectively welded and fixed to two ends of the second part 302. In some embodiments, the housing 300 is integrally arranged. The transmission assembly 400 is fixed or connected to the valve core 1, and the transmission assembly 400 includes a rotor 100, a screw rod 5 and a nut 200; one end of the screw rod 5 is limitedly connected to the valve core 1 in the axial direction, the screw rod 5 is penetrated by the nut 200, and the screw rod 5 and the nut 200 are threadedly matched, the nut 200 is fixedly connected to the valve seat 2, and the other end of the screw rod 5 is fixedly connected to the rotor 100. When the rotor 100 rotates, the screw rod 5 is driven to rotate together. Since the screw rod 5 and the nut 200 are threadedly matched, and the nut 200 is fixedly connected to the valve seat 2, the screw rod 5 will move up or down when it rotates, thereby driving the valve core 1 to move up or down.

[0024] The valve seat 2 has a valve port channel 20, which can be communicated with the valve cavity 3. The valve seat 2 includes a main body 21 and an extension portion 22. The extension portion 22 is connected to the main body 21, and the extension portion 22 extends toward the valve core 1 in the axial direction. The valve port channel 20 penetrates the main body 21 and the extension portion 22 in the axial direction; the extension portion 22 is sleeved on the valve core 1, and the valve core 1 can move in the axial direction along the extension portion 22 to connect the valve port channel 20 and the valve cavity 3 or block the valve port channel 20 from being connected with the valve cavity 3.

[0025] In this way, since the extension portion 22 is sleeved on the valve core 1, and the valve core 1 can move in the axial direction along the extension portion 22 to connect the valve port channel 20 and the valve cavity 3 or block the valve port channel 20 from being connected with the valve cavity 3, the extension portion 22 acts as a limit on the valve core 1, which is beneficial to reducing the displacement of the valve core 1 caused by the impact, thereby reducing the gap caused by the displacement of the valve core 1 when the valve core 1 closes the valve port channel 20.

[0026] The valve port channel 20 includes a first through section 201 and a second through section 203, the extension portion 22 constitutes at least a portion of the wall corresponding to the first through section 201, and the main body portion 21 constitutes at least a portion of the wall corresponding to the second through section 203. In the axial direction, the first through section 201 is farther away from the transmission assembly 400 than the second through section 203, and the inner diameter of the wall corresponding to the first through section 201 is greater than or equal to the outer diameter of the extension portion 22. The wall corresponding to the opening of the first through section 201 facing the transmission assembly 400 is provided with a chamfer to facilitate the valve core 1 to enter the first through section 201 during assembly; the valve core 1 is at least partially located in the first through section 201, and at least a portion of the valve core 1 is slidably matched with the wall corresponding to the first through section 201.

[0027] Since the valve core 1 is at least partially located in the valve port channel 20, and at least part of the valve core 1 is slidably matched with the wall corresponding to the first through section 201, the valve core 1 can move up and down along the extension portion 22 in the axial direction, and the extension portion 22 guides and limits the valve core 1, thereby reducing the deviation of the valve core 1.

[0028] The extension portion 22 has at least one flow hole 12 , and the flow hole 12 penetrates the wall corresponding to the valve port channel 20 in the radial direction; in some embodiments, the number of the flow holes 12 is at least two, and the flow holes 12 are evenly distributed along the circumferential direction of the side wall of the extension portion 22 .

[0029] One end of the flow hole 12 is connected to the valve cavity 3; the valve core 1 has a first position and a second position. In the first position, at least part of the wall corresponding to the flow hole 12 is closer to the body 21 than the valve core 1, and the other end of the flow hole 12 is connected to the valve port channel 20; in the second position, the projection of the wall corresponding to the flow hole 12 along the center line is located on the valve core 1, and the valve core 1 blocks the other end of the flow hole 12 from being connected to the valve port channel 20. During the normal operation of the electronic expansion valve, the extension portion 22 is always partially sleeved on the valve core 1.

[0030] Since the rotor 100 can drive the valve core 1 to move up and down, when the valve core 1 moves to the first position, the other end of the flow hole 12 is connected to the valve port channel 20, and the fluid in the valve cavity 3 can flow into the valve port channel 20 through the flow hole 12; when the valve core 1 moves to the second position, the extension part 22 blocks the communication between the flow hole 12 and the valve port channel 20 in the radial direction.

[0031] The valve core 1 has an abutting end 13, and the wall corresponding to the valve port channel 20 is provided with a first step portion 202. In the axial direction, the first step portion 202 is farther away from the transmission assembly 400 than the valve core 1, and the abutting end 13 faces the first step portion 202; in the axial direction, at least part of the projection of the abutting end 13 is located at the first step portion 202.

[0032] The valve seat 2 further includes a sealing gasket 4, which is located between the abutting end 13 and the first step 202, and in the axial direction, at least part of the projection of the abutting end 13 is located on the sealing gasket 4; in some embodiments, the sealing gasket 4 is made of a soft material, specifically soft metal or rubber or plastic or nylon. The abutting end 13 is provided with a tip 131 facing the sealing gasket 4, and when the valve core 1 is in the second position, the tip 131 abuts against the sealing gasket 4.

[0033] In this embodiment, the flow hole 12 includes a first flow section 121, a second flow section 122 and a third flow section 123. In the axial direction, the first flow section 121 and the third flow section 123 are respectively located on both sides of the second flow section 122; along the axial direction and toward the valve seat 2, the spacing between the walls corresponding to the first flow section 121 gradually increases, the spacing between the walls corresponding to the second flow section 122 is constant, and the spacing between the walls corresponding to the third flow section 123 gradually decreases. Specifically, the cross-sections corresponding to the first flow section 121 and the second flow section 122 are semicircular.

[0034] The side wall of the valve seat 2 is provided with a second step portion 23 facing the housing 300. The housing 300 is at least partially sleeved on the valve seat 2, and the housing 300 is welded and fixed to the second step portion 23. The valve seat 2 has a guide portion 24. In the radial direction, the guide portion 24 is located between the second step portion 23 and the extension portion 22. In the axial direction and in the direction toward the housing 300, the diameter of the guide portion 24 gradually decreases. In this way, during assembly, the guide portion 24 plays a guiding role so that the housing 300 can be sleeved on the valve seat 2.

[0035] The transmission assembly 400 also includes a limit member 6, and the screw rod 5 is limitedly connected or fixedly connected to the limit member 6 in the axial direction. In this embodiment, the screw rod 5 is inserted into the valve core 1, and the end of the screw rod 5 is fixedly connected to the limit member 6. In some embodiments, the screw rod 5 and the limit member 6 are clamped.

[0036] In the axial direction, the stopper 6 is closer to the main body 21 than at least part of the valve core 1, and in the axial direction, the projection of part of the stopper 6 is located on the valve core 1, so that the stopper 6 and the valve core 1 are limited in the axial direction, and when the screw rod 5 rotates and moves upward, the screw rod 5 can drive the valve core 1 to move upward through the stopper 6. The sealing gasket 4 is located at the outer periphery of the stopper 6, and a gap is left between the sealing gasket 4 and the stopper 6 to prevent the stopper 6 from interfering with the sealing gasket 4 when moving.

[0037] The transmission assembly 400 further includes an elastic member 7; the screw rod 5 includes a main body 51 and a second flange 52, and the second flange 52 protrudes from the main body 51 in the radial direction; the elastic member 7 is sleeved on the screw rod 5, and in the axial direction, at least part of the valve core 1 is located between the elastic member 7 and the stopper 6. In this embodiment, the elastic member 7 is a spring. In the axial direction, the two ends of the elastic member 7 are directly or indirectly in contact with the valve core 1 and the second flange 52, respectively, and the elastic member 7 is in a compressed state. In this embodiment, there is also a retaining spring between the elastic member 7 and the second flange 52, and the elastic member 7 is in contact with the retaining spring, and the retaining spring is in contact with the second flange 52. In this way, in the axial direction, at least part of the valve core 1 is located between the elastic member 7 and the limit member 6, that is, the screw rod 5 and the valve core 1 realize a limit connection; when the screw rod 5 rotates and moves downward, the screw rod 5 drives the valve core 1 to move downward, and when the valve core 1 moves down to the abutting end 13 and abuts against the sealing gasket 4, the valve core 1 stops moving downward. At this time, the screw rod 5 will also rotate and move downward for a distance, thereby compressing the elastic member 7 to ensure the reliability of the abutment seal between the sealing gasket 4 and the valve core 1 (specifically the abutting end 13).

[0038] The electronic expansion valve also includes a guide sleeve 8, which has a guide channel 81 that runs through its body; the guide sleeve 8 is located in the valve cavity 3, and the guide sleeve 8 is fixed to the housing 300, specifically welded; the guide sleeve 8 is coaxially arranged with the extension portion 22; the valve core 1 is at least partially located in the guide channel 81, and the valve core 1 and the wall corresponding to the guide channel 81 are slidably matched; a sealing member 9 is provided between the valve core 1 and the wall corresponding to the guide channel 81. In this way, the guide sleeve 8 guides and limits the valve core 1, reduces the displacement of the upper end of the valve core 1, and avoids the valve core 1 from getting stuck during the up and down movement.

[0039] In the figure, L is the circumference of the outer periphery of the valve core 1, and x is the opening (that is, the degree to which the flow hole 12 is opened in the axial direction).

[0040] Figure 7 A second embodiment is shown. In this embodiment,

[0041] The flow hole 12 includes a first flow section 121 and a third flow section 123, and the first flow section 121 is connected to the third flow section 123; along the axial direction and toward the valve seat 2, the spacing between the walls corresponding to the first flow section 121 gradually increases, and the spacing between the walls corresponding to the third flow section 123 gradually decreases. Specifically, the cross-section of the flow hole 12 is circular; the distance difference between the centers (i.e., the centers of the circles) of two adjacent flow holes 12 in the axial direction is zero.

[0042] Figure 8 A third embodiment is shown. In this embodiment,

[0043] The flow holes 12 are arranged in a wave shape along the circumferential direction, and the absolute value of the distance difference between the centers of any two adjacent flow holes 12 (in this embodiment, the cross section of the flow holes 12 is circular, and the center is the center of the circle) in the axial direction is the same, and the distance between the centers of any two adjacent flow holes 12 in the circumferential direction is the same. In this way, the functional relationship between the conduction area corresponding to the flow holes 12 and the opening is closer to linear, so that the flow rate can be easily controlled.

[0044] Fig. 9 A fourth embodiment is shown. In this embodiment,

[0045] The abutting end portion 13 includes an abutting surface portion 14. In the axial direction and in the direction from the transmission component toward the valve seat, the outer diameter corresponding to the abutting surface portion 14 gradually decreases. In the axial direction, the projection of the sealing gasket 4 is at least partially located on the abutting surface portion 14, and the inner diameter of the sealing gasket 4 (in this embodiment, the sealing gasket is annular) is smaller than the maximum value of the outer diameter corresponding to the abutting surface portion 14, and the inner diameter of the sealing gasket 4 is larger than the minimum value of the outer diameter corresponding to the abutting surface portion 14. When the valve core 1 is in the second position, the abutting surface portion 14 is in sealing contact with the sealing gasket 4. In this embodiment, the cross section corresponding to the abutting surface portion 14 is an inclined surface, and in some embodiments, the cross section corresponding to the abutting surface portion 14 is a curved surface.

[0046] Fig.10 A fifth embodiment is shown. In this embodiment,

[0047] The valve seat 2 does not include a sealing gasket 4; in the axial direction, the projection of the first step portion 202 is at least partially located on the abutting surface portion 14, and the inner diameter of the first step portion 202 is smaller than the maximum value of the outer diameter corresponding to the abutting surface portion, and larger than the minimum value of the outer diameter corresponding to the abutting surface portion; when the valve core 1 is in the second position, the abutting surface portion 14 is in sealing contact with the first step portion 202.

[0048] It should be noted that:

[0049] In the present invention, the axial direction refers to the axial direction of the electronic expansion valve body, and the radial direction in the text refers to the radial direction of the electronic expansion valve body;

[0050] The terms "first", "second", "third", "fourth" and "fifth" are used for descriptive purposes only and shall not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features;

[0051] Although this specification has described the present application in detail with reference to the above-mentioned implementation modes, a person of ordinary skill in the art should understand that a person of ordinary skill in the art can still modify, combine or make equivalent substitutions to the present application, and all technical solutions and improvements thereof that do not depart from the spirit and scope of the present application should be included in the scope of the claims of the present application.

Claims

1. An electronic expansion valve, comprising a housing (300), a valve core (1), a valve seat (2) and a transmission assembly (400), and also comprising a valve chamber (3), wherein the housing (300) is fixed to the valve seat (2), the transmission assembly (400) is fixed to or connected to the valve core (1) to drive the valve core (1) to move closer to or farther from the valve seat (2), the valve seat (2) having a valve port channel (20), the valve port channel (20) being able to communicate with the valve chamber (3), It is characterized in that The valve seat (2) comprises a main body portion (21) and an extension portion (22), wherein the extension portion (22) is connected to the main body portion (21), and the extension portion (22) extends toward the valve core (1) in an axial direction, and the valve port channel (20) penetrates the main body portion (21) and the extension portion (22) in an axial direction; The extension portion (22) is sleeved on the valve core (1), and the valve core (1) can move in the axial direction along the extension portion (22) to connect the valve port channel (20) and the valve cavity (3) or block the connection between the valve port channel (20) and the valve cavity (3).

2. An electronic expansion valve according to claim 1, characterized in that: The valve port channel (20) comprises a first through section (201) and a second through section (203); the extension portion (22) constitutes at least a portion of a wall corresponding to the first through section (201); the body portion (21) constitutes at least a portion of a wall corresponding to the second through section (203); and the inner diameter of the wall corresponding to the first through section (201) is greater than or equal to the outer diameter of the valve core (1); At least part of the valve core (1) is located in the first through section (201), and at least part of the valve core (1) is in sliding engagement with a wall corresponding to the first through section (201).

3. An electronic expansion valve according to claim 1, characterized in that: The extension portion (22) has at least one flow hole (12), and the flow hole (12) penetrates the wall corresponding to the valve port channel (20) in the radial direction; One end of the flow hole (12) is in communication with the valve chamber (3); The valve core (1) has a first position and a second position, In the first position, at least a portion of the wall corresponding to the circulation hole (12) is closer to the main body (21) than the valve core (1), and the other end of the circulation hole (12) is in communication with the valve port channel (20); In the second position, the projection of the wall corresponding to the circulation hole (12) along its centerline is located on the valve core (1), and the valve core (1) blocks the other end of the circulation hole (12) from communicating with the valve port channel (20).

4. An electronic expansion valve according to any one of claims 1 to 3, characterized in that: The valve core (1) has an abutting end portion (13), and a wall corresponding to the valve port channel (20) is provided with a first step portion (202). In the axial direction, the first step portion (202) is farther from the transmission assembly (400) than the valve core (1), and the abutting end portion (13) faces the first step portion (202); In the axial direction, at least a portion of the projection of the abutment end portion (13) is located on the first step portion (202).

5. An electronic expansion valve according to claim 4, characterized in that: The valve seat (2) further comprises a sealing gasket (4), wherein the sealing gasket (4) is located between the abutting end portion (13) and the first step portion (202), and in the axial direction, at least part of the projection of the abutting end portion (13) is located on the sealing gasket (4); The abutting end portion (13) is provided with a tip portion (131) facing the sealing gasket (4), and the tip portion (131) can abut against the sealing gasket (4), or The abutting end portion (13) comprises an abutting surface portion (14), and in the axial direction and in the direction from the transmission component toward the valve seat, the outer diameter corresponding to the abutting surface portion (14) gradually decreases, and in the axial direction, the projection of the sealing gasket (4) is at least partially located on the abutting surface portion (14), and the inner diameter of the sealing gasket (4) is smaller than the maximum value of the outer diameter corresponding to the abutting surface portion (14), and the inner diameter of the sealing gasket (4) is larger than the minimum value of the outer diameter corresponding to the abutting surface portion (14); the abutting surface portion (14) can be in sealing abutment with the sealing gasket (4).

6. An electronic expansion valve according to claim 3, characterized in that: The flow hole (12) comprises a first flow section (121), a second flow section (122) and a third flow section (123); in the axial direction, the first flow section (121) and the third flow section (123) are respectively located on both sides of the second flow section (122); In the axial direction and in the direction toward the valve seat (2), The distance between the walls corresponding to the first flow section (121) gradually increases. The spacing between the walls corresponding to the second flow section (122) is constant, The distance between the walls corresponding to the third flow section (123) gradually decreases.

7. An electronic expansion valve according to claim 3, characterized in that: The circulation hole (12) comprises a first circulation section (121) and a third circulation section (123), wherein the first circulation section (121) is connected to the third circulation section (123); In the axial direction and in the direction toward the valve seat (2), The distance between the walls corresponding to the first flow section (121) gradually increases. The distance between the walls corresponding to the third flow section (123) gradually decreases.

8. An electronic expansion valve according to claim 7, characterized in that: The number of the flow holes (12) is at least two; The distance difference between the centers corresponding to two adjacent circulation holes (12) in the axial direction is zero; or the circulation holes (12) are arranged in a wave shape along the circumferential direction, and the absolute value of the distance difference between the centers corresponding to any two adjacent circulation holes (12) in the axial direction is the same, and the distance between the centers corresponding to any two adjacent circulation holes (12) in the circumferential direction is the same.

9. The electronic expansion valve according to claim 1, characterized in that: The side wall of the valve seat (2) is provided with a second step portion (23) facing the shell (300); the shell (300) is at least partially sleeved on the valve seat (2); and the shell (300) and the second step portion (23) are fixed by welding.

10. An electronic expansion valve according to claim 9, characterized in that: The valve seat (2) has a guide portion (24), and in the radial direction, the guide portion (24) is located between the second step portion (23) and the extension portion (22); In the axial direction and in the direction toward the housing (300), the diameter of the guide portion (24) gradually decreases.

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