expansion valve

Abstract

The application provides an expansion valve, which comprises a valve seat, a valve sleeve and a valve needle, the cavity of the valve seat has a first end and a second end at two ends respectively, the valve sleeve is arranged in the cavity of the valve seat and is movably arranged along the axial direction of the valve seat, the valve needle is arranged in the cavity of the valve seat and at least a part of the valve needle is arranged in the valve sleeve, the valve needle is movably arranged along the axial direction of the valve seat, the area between the inner wall of the valve sleeve and the outer wall of the valve needle is a flow passage, the minimum cross section of the flow passage along the radial direction of the valve seat is a throttling surface, and the relative movement of the valve sleeve and the valve needle can adjust the area of the throttling surface. According to the scheme, when the fluid flows in any direction along the axial direction of the valve seat, the relative movement of the valve needle and the valve sleeve can be realized under the condition of meeting the pressure condition, so that the area of the throttling surface is increased, the throttling and the bidirectional flow of the expansion valve are realized. Compared with the existing expansion valve, the number of parts is simplified, the leakage points are reduced, so that the manufacturing cost can be reduced and the use effect can be improved.

Description

Technical Field

[0001] This invention relates to the field of expansion valve technology, and more specifically, to an expansion valve. Background Technology

[0002] Existing expansion valves with bidirectional flow function are usually of the dual-needle and dual-seat structure, which results in many parts and complex structure, leading to more leakage points and affecting manufacturing costs and performance. Summary of the Invention

[0003] This invention provides an expansion valve to simplify the structure of existing expansion valves.

[0004] To address the aforementioned problems, the present invention provides an expansion valve, comprising: a valve seat having a cavity, the two ends of which are a first end and a second end, respectively; a valve sleeve disposed within the cavity of the valve seat, the valve sleeve being movably disposed along the axial direction of the valve seat; a valve needle disposed within the cavity of the valve seat, at least a portion of the valve needle passing through the valve sleeve, the valve needle being movably disposed along the axial direction of the valve seat; the area between the inner wall of the valve sleeve and the outer wall of the valve needle is a flow cavity, the minimum cross-section of the flow cavity along the radial direction of the valve seat is a throttling surface, the relative movement of the valve sleeve and the valve needle can adjust the area of ​​the throttling surface, the throttling surface... The system has an initial state and an expanded state. The area of ​​the throttling surface in the expanded state is larger than the area in the initial state. Specifically, when the pressure difference between the fluids at the first end and the second end is within a preset range, the throttling surface is in the initial state. When the fluid pressure at the first end exceeds the fluid pressure at the second end by a value exceeding the preset range, the valve needle moves away from the valve sleeve to switch the throttling surface to the expanded state. When the fluid pressure at the second end exceeds the fluid pressure at the first end by a value exceeding the preset range, the valve sleeve moves away from the valve needle to switch the throttling surface to the expanded state.

[0005] Furthermore, the inner wall of the valve seat has a first step, which is used to limit the displacement of the valve sleeve in the direction of the valve needle. The expansion valve also includes a first elastic element, one end of which abuts against the end of the valve sleeve away from the valve needle.

[0006] Furthermore, the valve sleeve includes a first sleeve segment and a second sleeve segment connected to each other. The outer diameter of the first sleeve segment is larger than the outer diameter of the second sleeve segment. At least a portion of the valve needle passes through the second sleeve segment. One side of the first sleeve segment abuts against the first elastic member, and the other side of the first sleeve segment is used to cooperate with the first step for limiting.

[0007] Furthermore, the expansion valve further includes: a first positioning sleeve, which is connected to one end of the valve seat, and the other end of the first elastic element abuts against the first positioning sleeve.

[0008] Furthermore, at least one of the inner wall of the valve sleeve and the outer wall of the valve needle has a tapered surface or an inclined surface; when the valve sleeve and the valve needle are far apart, the area of ​​the throttling surface gradually increases; when the valve sleeve and the valve needle are close together, the area of ​​the throttling surface gradually decreases.

[0009] Furthermore, the valve needle includes a seat and a needle body connected to each other, the radial dimension of the seat body is greater than the radial dimension of the needle body, at least a portion of the needle body passes through the valve sleeve, and the outer wall of the needle body has a tapered surface or an inclined surface.

[0010] Furthermore, the seat body has a through hole that connects the regions located at both ends of the seat body within the valve seat cavity; and / or, a flow groove is provided between the outer wall of the seat body and the inner wall of the valve seat cavity, the flow groove connecting the regions located at both ends of the seat body within the valve seat cavity.

[0011] Furthermore, the inner wall of the valve seat has a second step, which is used to limit the side of the seat body facing the valve sleeve. The expansion valve also includes a second elastic member, one end of which abuts against the end of the seat body away from the valve sleeve.

[0012] Furthermore, the expansion valve also includes a second positioning sleeve, which is connected to one end of the valve seat, and the other end of the second elastic element abuts against the second positioning sleeve.

[0013] Furthermore, the expansion valve also includes a connecting pipe, wherein the valve seat is disposed within the connecting pipe and the valve seat is fixedly connected to the connecting pipe.

[0014] The present invention provides an expansion valve comprising a valve seat, a valve sleeve, and a valve needle. The valve seat has a cavity with two ends, a first end and a second end, respectively. The valve sleeve is disposed within the cavity of the valve seat and is movably disposed along the axial direction of the valve seat. The valve needle is disposed within the cavity of the valve seat, with at least a portion of the valve needle passing through the valve sleeve and movably disposed along the axial direction of the valve seat. The area between the inner wall of the valve sleeve and the outer wall of the valve needle forms a flow cavity. When the pressure difference between the fluids at the first end and the second end is within a preset range, the throttling surface is in its initial state. When the fluid pressure at the first end exceeds the fluid pressure at the second end by a value exceeding the preset range, the valve needle moves away from the valve sleeve to switch the throttling surface to an expansion state. When the fluid pressure at the second end exceeds the fluid pressure at the first end by a value exceeding the preset range, the valve sleeve moves away from the valve needle to switch the throttling surface to an expansion state. This design allows for relative movement between the valve needle and valve sleeve when fluid flows axially in either direction on the valve seat, provided the pressure conditions are met. This increases the throttling surface area, achieving throttling and enabling bidirectional flow in the expansion valve. Compared to existing expansion valves, this design eliminates the need for a dual-needle, dual-seat structure, simplifying the number of parts, reducing leakage points, thereby lowering manufacturing costs and improving performance. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0016] Figure 1 A schematic diagram of the expansion valve provided in an embodiment of the present invention is shown;

[0017] Figure 2 It shows Figure 1 A schematic diagram of the expansion valve in the open state;

[0018] Figure 3 It shows Figure 1 Another schematic diagram of the expansion valve in the open state;

[0019] Figure 4 It shows Figure 3 A three-dimensional image;

[0020] Figure 5 It shows Figure 1 Schematic diagram of valve needle Figure 1 ;

[0021] Figure 6 It shows Figure 5 A cross-sectional view of the valve needle in the image;

[0022] Figure 7 It shows Figure 1Schematic diagram of valve needle Figure 2 ;

[0023] Figure 8 It shows Figure 7 A cross-sectional view of the valve needle in the image;

[0024] Figure 9 It shows Figure 1 Schematic diagram of valve needle Figure 3 ;

[0025] Figure 10 It shows Figure 9 A cross-sectional view of the valve needle in the image;

[0026] Figure 11 It shows Figure 1 A schematic diagram of the valve sleeve in the diagram;

[0027] Figure 12 It shows Figure 11 A sectional view of the valve sleeve.

[0028] The above figures include the following reference numerals:

[0029] 10. Valve seat; 20. Valve sleeve; 21. First sleeve section; 22. Second sleeve section; 30. Valve needle; 31. Seat body; 32. Needle body; 33. Inclined surface; 34. Through hole; 41. First elastic element; 42. Second elastic element; 51. First positioning sleeve; 52. Second positioning sleeve; 60. Connecting pipe. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0031] As shown in the attached figures, an embodiment of the present invention provides an expansion valve, comprising: a valve seat 10 having a cavity, the two ends of which are a first end and a second end, respectively; a valve sleeve 20 disposed within the cavity of the valve seat 10, the valve sleeve 20 being movably disposed along the axial direction of the valve seat 10; a valve needle 30 disposed within the cavity of the valve seat 10, at least a portion of the valve needle 30 passing through the valve sleeve 20, the valve needle 30 being movably disposed along the axial direction of the valve seat 10; the area between the inner wall of the valve sleeve 20 and the outer wall of the valve needle 30 is a flow cavity, the minimum cross-section of the flow cavity along the radial direction of the valve seat 10 is a throttling surface, and the relative movement of the valve sleeve 20 and the valve needle 30 adjusts the area of ​​the throttling surface; the area of ​​the throttling surface is... When the pressure difference is zero, the first and second ends are disconnected, and the expansion valve is closed. When the area of ​​the throttling surface is greater than zero, the first and second ends are connected, and the expansion valve is open. When the pressure difference between the fluids in the first and second ends is within a preset range, the expansion valve is closed. When the fluid pressure in the first end exceeds the fluid pressure in the second end by more than a preset range, the valve needle 30 moves away from the valve sleeve 20 under the action of the pressure difference, so that the expansion valve switches to the open state. When the fluid pressure in the second end exceeds the fluid pressure in the first end by more than a preset range, the valve sleeve 20 moves away from the valve needle 30 under the action of the pressure difference, so that the expansion valve switches to the open state.

[0032] According to the technical solution of the present invention, an expansion valve is provided, which includes a valve seat 10, a valve sleeve 20, and a valve needle 30. The two ends of the cavity of the valve seat 10 are a first end and a second end, respectively. The valve sleeve 20 is disposed in the cavity of the valve seat 10 and is movably disposed along the axial direction of the valve seat 10. The valve needle 30 is disposed in the cavity of the valve seat 10, and at least a portion of the valve needle 30 passes through the valve sleeve 20 and is movably disposed along the axial direction of the valve seat 10. The area between the inner wall of the valve sleeve 20 and the outer wall of the valve needle 30 is a flow cavity. When the pressure difference of the fluid in the first end and the second end is within a preset range, the throttling surface is in the initial state. When the fluid pressure in the first end is greater than the fluid pressure in the second end by a value exceeding the preset range, the valve needle 30 moves away from the valve sleeve 20 to switch the throttling surface to an expansion state. When the fluid pressure in the second end is greater than the fluid pressure in the first end by a value exceeding the preset range, the valve sleeve 20 moves away from the valve needle 30 to switch the throttling surface to an expansion state. This design allows for relative movement of the valve needle 30 and valve sleeve 20 when the fluid flows axially in either direction of the valve seat 10, provided the pressure conditions are met. This increases the throttling surface area, enabling throttling and flow regulation, and achieving bidirectional flow in the expansion valve. Compared to existing expansion valves, this design eliminates the need for a double-valve-needle, double-valve-seat structure, simplifying the number of parts, reducing leakage points, thereby lowering manufacturing costs and improving performance.

[0033] Specifically, the flow chamber is the cavity in the overlapping area of ​​the valve sleeve 20 and the valve needle 30 along the axial direction of the valve seat 10. Both the valve sleeve 20 and the valve needle 30 are driven by the pressure difference of the fluid to achieve relative movement between them. The area of ​​the throttling surface in the initial state is zero or greater than zero; when the area of ​​the throttling surface is greater than zero, the first end and the second end are connected. In this application, the area of ​​the throttling surface in the initial state is greater than zero, meaning the expansion valve still has a certain flow capacity, which can reduce the noise of the applied equipment during start-up and shutdown.

[0034] In this embodiment, the inner wall of the valve seat 10 has a first step, which is used to limit the displacement of the valve sleeve 20 in the direction toward the valve needle 30. The expansion valve also includes a first elastic member 41, one end of which abuts against the end of the valve sleeve 20 away from the valve needle 30. With the above configuration, the valve sleeve 20 can be limited in two axial directions to limit the range of movement of the valve sleeve 20.

[0035] In this embodiment, the valve sleeve 20 includes a first sleeve segment 21 and a second sleeve segment 22 connected to each other. The outer diameter of the first sleeve segment 21 is larger than the outer diameter of the second sleeve segment 22. At least a portion of the valve needle 30 passes through the second sleeve segment 22. One side of the first sleeve segment 21 abuts against the first elastic member 41, and the other side of the first sleeve segment 21 is used to cooperate with the first step for limiting.

[0036] In this embodiment, the expansion valve further includes a first positioning sleeve 51, which is connected to one end of the valve seat 10, and the other end of the first elastic member 41 abuts against the first positioning sleeve 51. Thus, the first positioning sleeve 51 can limit and guide the first elastic member 41.

[0037] Optionally, the first positioning sleeve 51 includes a first segment, a second segment, and a third segment connected in sequence. The outer diameter of the first segment is larger than the outer diameter of the second segment, and the inner diameter of the second segment is larger than the inner diameter of the third segment. A first elastic member 41 is inserted into the second segment, and the end of the first elastic member 41 abuts against the third segment. The first segment is riveted to the valve seat 10. The third segment has an opening for fluid flow.

[0038] In this embodiment, at least one of the inner wall of the valve sleeve 20 and the outer wall of the valve needle 30 has a tapered surface or an inclined surface 33; when the valve sleeve 20 and the valve needle 30 are far apart, the area of ​​the throttling surface increases; when the valve sleeve 20 and the valve needle 30 are close together, the area of ​​the throttling surface decreases. Through the above configuration, as... Figure 1As shown in the diagram, when there is high pressure above, the valve needle 30 opens under the pressure difference, maintaining a certain opening to achieve throttling. The greater the pressure difference, the greater the downward opening of the valve needle 30, and the greater the flow capacity. When there is high pressure below, the valve sleeve 20 opens under the pressure difference, maintaining a certain opening to achieve throttling. The greater the pressure difference, the greater the upward opening of the valve sleeve 20, and the greater the flow capacity, thus achieving bidirectional flow regulation. When the pressure difference is small, the valve needle 30 and valve sleeve 20 are positioned on the valve seat 10. At this time, the area of ​​the throttling surface is greater than zero, ensuring that the expansion valve has a certain flow capacity at low pressure and reducing fluid noise during start-up and shutdown.

[0039] In this embodiment, the valve needle 30 includes a seat 31 and a needle body 32 connected to each other. The radial dimension of the seat 31 is larger than the radial dimension of the needle body 32. At least a portion of the needle body 32 passes through the valve sleeve 20, and the outer wall of the needle body 32 has a tapered surface or an inclined surface 33. The tapered surface or inclined surface 33 on the outer wall of the needle body 32 allows the area of ​​the throttling surface to change when the needle body 32 and the valve sleeve 20 undergo relative displacement, thereby achieving flow regulation. This design is simple in structure and facilitates precise flow regulation. Specifically, the inclined surface 33 is inclined relative to the axis of the needle body 32.

[0040] In this embodiment, the seat 31 has a through hole 34 that connects the regions located at both ends of the seat 31 within the valve seat 10 cavity; and / or, a flow groove is provided between the outer wall of the seat 31 and the inner wall of the valve seat 10 cavity, connecting the regions located at both ends of the seat 31 within the valve seat 10 cavity. Through the above configuration, the regions at both ends of the seat 31 can be connected, thereby enabling fluid flow.

[0041] Optionally, the base 31 includes a cylindrical body and an end plate disposed at one end of the cylindrical body. The needle body 32 is disposed on the end plate. The side wall of the cylindrical body has an opening, one end of which is located on the end plate, and the other end of which communicates with the cavity of the cylindrical body. The opening on the side wall of the cylindrical body and the cavity inside the cylindrical body form a through hole 34.

[0042] Optionally, the inner wall of the valve seat 10 cavity is cylindrical, and the outer wall of the seat 31 has a plane, with the area between the plane and the inner wall being a flow groove.

[0043] In this embodiment, the inner wall of the valve seat 10 has a second step, which is used to limit the side of the seat 31 facing the valve sleeve 20. The expansion valve also includes a second elastic member 42, one end of which abuts against the end of the seat 31 away from the valve sleeve 20. With the above configuration, the movement range of the valve needle 30 can be limited by the second step and the second elastic member 42. Moreover, when the pressure is low, the second elastic member 42 can keep the valve needle 30 in its initial position.

[0044] In this embodiment, the expansion valve further includes a second positioning sleeve 52, which is connected to one end of the valve seat 10, and the other end of the second elastic member 42 abuts against the second positioning sleeve 52. The second positioning sleeve 52 can limit and guide the second elastic member 42. Specifically, the structure of the second positioning sleeve 52 is the same as that of the first positioning sleeve.

[0045] In this embodiment, the expansion valve further includes a connecting pipe 60, a valve seat 10 disposed within the connecting pipe 60, and the valve seat 10 being fixedly connected to the connecting pipe 60. The connecting pipe 60 facilitates fluid flow and connection to other pipelines.

[0046] Optionally, the outer wall of the valve seat 10 has an annular groove, and the inner wall of the connecting pipe 60 has an annular protrusion. The annular protrusion engages with the annular groove, thereby achieving a reliable connection between the two.

[0047] In an embodiment not shown, the first positioning sleeve 51 or the second positioning sleeve 52 may have an end cap structure.

[0048] In an embodiment not shown, the valve sleeve 20 may be disposed within the first positioning sleeve 51, the first positioning sleeve 51 and the valve sleeve 20 being an integral structure, and the valve needle 30 may be disposed within the second positioning sleeve 52, the second positioning sleeve 52 and the valve sleeve 20 being an integral structure.

[0049] According to the technical solution of the present invention, an expansion valve is provided, which includes a valve seat 10, a valve sleeve 20, and a valve needle 30. The two ends of the cavity of the valve seat 10 are a first end and a second end, respectively. The valve sleeve 20 is disposed in the cavity of the valve seat 10 and is movably disposed along the axial direction of the valve seat 10. The valve needle 30 is disposed in the cavity of the valve seat 10, and at least a portion of the valve needle 30 passes through the valve sleeve 20 and is movably disposed along the axial direction of the valve seat 10. The area between the inner wall of the valve sleeve 20 and the outer wall of the valve needle 30 is a flow cavity. When the pressure difference of the fluid in the first end and the second end is within a preset range, the throttling surface is in the initial state. When the fluid pressure in the first end is greater than the fluid pressure in the second end by a value exceeding the preset range, the valve needle 30 moves away from the valve sleeve 20 to switch the throttling surface to an expansion state. When the fluid pressure in the second end is greater than the fluid pressure in the first end by a value exceeding the preset range, the valve sleeve 20 moves away from the valve needle 30 to switch the throttling surface to an expansion state. This design allows for relative movement between the valve needle 30 and the valve sleeve 20 when fluid flows axially in either direction on the valve seat 10, provided the pressure conditions are met. This increases the throttling surface area, enabling throttling and flow regulation, and achieving bidirectional flow in the expansion valve. Compared to existing expansion valves, this design eliminates the need for a double-needle, double-seat structure, simplifying the number of parts, reducing leakage points, thereby lowering manufacturing costs and improving performance.

[0050] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An expansion valve, characterized in that, include: Valve seat (10), the valve seat (10) has a cavity, the two ends of the cavity of the valve seat (10) are a first end and a second end, respectively; A valve sleeve (20) is disposed in the cavity of the valve seat (10), and the valve sleeve (20) is movably disposed along the axial direction of the valve seat (10); A valve needle (30) is disposed in the cavity of the valve seat (10), at least a portion of the valve needle (30) passes through the valve sleeve (20), and the valve needle (30) is movably disposed along the axial direction of the valve seat (10). The area between the inner wall of the valve sleeve (20) and the outer wall of the valve needle (30) is a flow cavity. The minimum cross section of the flow cavity along the radial direction of the valve seat (10) is a throttling surface. The relative movement of the valve sleeve (20) and the valve needle (30) can adjust the area of ​​the throttling surface. The throttling surface has an initial state and an expanded state. The area of ​​the throttling surface in the expanded state is greater than the area in the initial state. Wherein, when the pressure difference between the fluid in the first end and the second end is within a preset range, the throttling surface is in the initial state; when the fluid pressure in the first end is greater than the fluid pressure in the second end by a value exceeding the preset range, the valve needle (30) moves away from the valve sleeve (20) to switch the throttling surface to the expansion state; when the fluid pressure in the second end is greater than the fluid pressure in the first end by a value exceeding the preset range, the valve sleeve (20) moves away from the valve needle (30) to switch the throttling surface to the expansion state. When the area of ​​the throttling surface is greater than zero, the first end and the second end are connected; The valve seat (10) has a first step on its inner wall, which is used to limit the displacement of the valve sleeve (20) in the direction toward the valve needle (30). The valve needle (30) includes a seat (31), and the inner wall of the valve seat (10) also has a second step, which is used to limit the side of the seat (31) facing the valve sleeve (20).

2. The expansion valve according to claim 1, characterized in that, The expansion valve also includes: A first elastic element (41) is formed, one end of which abuts against the end of the valve sleeve (20) away from the valve needle (30).

3. The expansion valve according to claim 2, characterized in that, The valve sleeve (20) includes a first sleeve segment (21) and a second sleeve segment (22) connected to each other. The outer diameter of the first sleeve segment (21) is larger than the outer diameter of the second sleeve segment (22). At least a portion of the valve needle (30) passes through the second sleeve segment (22). One side of the first sleeve segment (21) abuts against the first elastic member (41), and the other side of the first sleeve segment (21) is used to cooperate with the first step for limiting.

4. The expansion valve according to claim 2, characterized in that, The expansion valve also includes: The first positioning sleeve (51) is connected to one end of the valve seat (10), and the other end of the first elastic element (41) abuts against the first positioning sleeve (51).

5. The expansion valve according to claim 1, characterized in that, At least one of the inner wall of the valve sleeve (20) and the outer wall of the valve needle (30) has a tapered surface or an inclined surface (33); when the valve sleeve (20) and the valve needle (30) are far apart from each other, the area of ​​the throttling surface gradually increases; when the valve sleeve (20) and the valve needle (30) are close to each other, the area of ​​the throttling surface gradually decreases.

6. The expansion valve according to claim 1, characterized in that, The valve needle (30) also includes a needle body (32) connected to the seat (31). The radial dimension of the seat (31) is greater than the radial dimension of the needle body (32). At least a portion of the needle body (32) passes through the valve sleeve (20). The outer wall of the needle body (32) has a tapered surface or a slope (33).

7. The expansion valve according to claim 6, characterized in that, The seat (31) has a through hole (34) that connects the regions located at both ends of the seat (31) within the cavity of the valve seat (10); and / or, There is a flow groove between the outer wall of the seat (31) and the inner wall of the valve seat (10) cavity, and the flow groove connects the regions located at both ends of the seat (31) in the valve seat (10) cavity.

8. The expansion valve according to claim 6, characterized in that, The expansion valve also includes: The second elastic element (42) has one end abutting against the end of the seat (31) away from the valve sleeve (20).

9. The expansion valve according to claim 8, characterized in that, The expansion valve also includes: The second positioning sleeve (52) is connected to one end of the valve seat (10), and the other end of the second elastic member (42) abuts against the second positioning sleeve (52).

10. The expansion valve according to claim 1, characterized in that, The expansion valve also includes: Connector (60), valve seat (10) is disposed inside the connector (60), and valve seat (10) is fixedly connected to the connector (60).

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