1. An expansion valve, comprising:

the valve seat (10), the valve seat (10) has a cavity, and two ends of the cavity of the valve seat (10) are respectively a first end and a second end;

a valve sleeve (20) arranged in the cavity of the valve seat (10), wherein the valve sleeve (20) is movably arranged along the axial direction of the valve seat (10);

a valve needle (30) arranged in the cavity of the valve seat (10), at least one part of the valve needle (30) is arranged in the valve sleeve (20) in a penetrating way, and the valve needle (30) is movably arranged 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-through cavity, the minimum cross section of the flow-through 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 expansion state, and the area of the throttling surface in the expansion state is larger than that in the initial state;

wherein the throttle surface is in an initial state when the pressure difference of the fluid in the first end and the second end is within a preset range; when the fluid pressure in the first end is greater than the fluid pressure in the second end by a value outside the preset range, the valve needle (30) moves away from the valve sleeve (20) to switch the throttle surface to the expanded state; when the fluid pressure in the second end is greater than the fluid pressure in the first end by a value outside the predetermined range, the valve sleeve (20) is moved away from the valve needle (30) to switch the throttle surface to the expanded state.

2. An expansion valve according to claim 1, wherein the valve seat (10) has a first step on its inner wall for limiting the displacement of the valve sleeve (20) in a direction towards the valve needle (30), the expansion valve further comprising:

a first elastic member (41), wherein one end of the first elastic member (41) abuts against one end of the valve sleeve (20) far away from the valve needle (30).

3. An expansion valve according to claim 2, wherein the valve housing (20) comprises a first sleeve section (21) and a second sleeve section (22) connected to each other, the first sleeve section (21) having an outer diameter larger than the outer diameter of the second sleeve section (22), at least a part of the valve needle (30) being arranged in the second sleeve section (22) in a penetrating manner, one side of the first sleeve section (21) abutting the first resilient member (41) and the other side of the first sleeve section (21) being adapted to form a positive fit with the first step.

4. An expansion valve according to claim 2, further comprising:

the first positioning sleeve (51), the first positioning sleeve (51) is connected with one end of the valve seat (10), and the other end of the first elastic piece (41) is abutted to the first positioning sleeve (51).

5. An expansion valve according to claim 1, wherein at least one of the inner wall of the valve sleeve (20) and the outer wall of the valve needle (30) has a conical or bevelled surface (33); the area of the throttling surface is gradually increased under the condition that the valve sleeve (20) and the valve needle (30) are far away from each other; the area of the throttle surface is gradually reduced when the valve sleeve (20) and the valve needle (30) approach each other.

6. An expansion valve according to claim 1, wherein the valve needle (30) comprises a seat (31) and a needle body (32) connected to each other, the radial dimension of the seat (31) being larger than the radial dimension of the needle body (32), at least a part of the needle body (32) being arranged through the valve housing (20), the outer wall of the needle body (32) having a conical or beveled surface (33).

7. An expansion valve according to claim 6,

the seat body (31) is internally provided with a through hole (34), and the through hole (34) is used for communicating areas positioned at two ends of the seat body (31) in the cavity of the valve seat (10); and/or the presence of a gas in the gas,

a circulation groove is formed between the outer wall of the seat body (31) and the inner wall of the cavity of the valve seat (10), and the circulation groove communicates the areas, located at the two ends of the seat body (31), in the cavity of the valve seat (10).

8. An expansion valve according to claim 6, wherein the valve seat (10) has a second step on its inner wall for limiting the side of the seat body (31) facing the valve sleeve (20), the expansion valve further comprising:

and one end of the second elastic piece (42) is abutted with one end of the seat body (31) far away from the valve sleeve (20).

9. An expansion valve according to claim 8, further comprising:

and the second positioning sleeve (52), the second positioning sleeve (52) is connected with one end of the valve seat (10), and the other end of the second elastic piece (42) is abutted against the second positioning sleeve (52).

10. An expansion valve according to claim 1, further comprising:

the connecting pipe (60), the valve seat (10) is arranged in the connecting pipe (60), and the valve seat (10) is fixedly connected with the connecting pipe (60).

Background

The existing expansion valve with the bidirectional flow function is generally of a double-valve needle double-valve seat structure, so that the expansion valve has multiple parts and a complex structure, so that multiple leakage points are caused, and the manufacturing cost and the using effect are influenced.

Disclosure of Invention

The invention provides an expansion valve, which is used for simplifying the structure of the existing expansion valve.

In order to solve the above problems, the present invention provides an expansion valve comprising: the valve seat is provided with a cavity, and a first end and a second end are respectively arranged at two ends of the cavity of the valve seat; 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 a cavity of the valve seat, at least one part of the valve needle penetrates through the valve sleeve, and 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-through cavity, the minimum cross section of the flow-through 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 has an initial state and an expansion state, and the area of the throttling surface in the expansion state is larger than that in the initial state; wherein the throttle surface is in an initial state when the pressure difference of the fluid in the first end and the second end is within a preset range; when the value of the fluid pressure in the first end is larger than the value of the fluid pressure in the second end and exceeds the preset range, the valve needle moves away from the valve sleeve so as 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 outside the preset range, the valve sleeve moves in a direction away from the valve needle to switch the throttle surface to the expanded state.

Further, the inner wall of the valve seat has a first step, and the first step is used for limiting the displacement of the valve sleeve towards the valve needle direction, and the expansion valve further includes: and one end of the first elastic piece is abutted with one end of the valve sleeve, which is far away from the valve needle.

Further, the valve sleeve comprises a first sleeve section and a second sleeve section which are connected with each other, the outer diameter of the first sleeve section is larger than that of the second sleeve section, at least one part of the valve needle penetrates through the second sleeve section, one side of the first sleeve section is abutted to the first elastic part, and the other side of the first sleeve section is used for being in limit fit with the first step.

Further, the expansion valve further includes: the first positioning sleeve is connected with one end of the valve seat, and the other end of the first elastic piece is abutted to the first positioning sleeve.

Further, at least one of the inner wall of the valve sleeve and the outer wall of the valve needle has a tapered surface or a slant surface; under the condition that the valve sleeve and the valve needle are far away from each other, the area of the throttling surface is gradually increased; the area of the throttle surface is gradually reduced in the case where the valve sleeve and the valve needle approach each other.

Further, the valve needle comprises a seat body and a needle body which are connected with each other, the radial dimension of the seat body is larger than that of the needle body, at least one part of the needle body penetrates through the valve sleeve, and the outer wall of the needle body is provided with a conical surface or an inclined surface.

Furthermore, the seat body is internally provided with a through hole which communicates the areas positioned at the two ends of the seat body in the valve seat cavity; and/or a circulation groove is arranged between the outer wall of the seat body and the inner wall of the valve seat cavity, and the circulation groove communicates the areas, which are positioned at the two ends of the seat body, in the valve seat cavity.

Further, the inner wall of the valve seat is provided with a second step, the second step is used for limiting one side of the valve sleeve facing the seat body, and the expansion valve further comprises: and one end of the second elastic piece is abutted with one end of the seat body, which is far away from the valve sleeve.

Further, the expansion valve further includes: and the second positioning sleeve is connected with one end of the valve seat, and the other end of the second elastic piece is abutted against the second positioning sleeve.

Further, the expansion valve further includes: and the valve seat is arranged in the connecting pipe and is fixedly connected with the connecting pipe.

The technical scheme of the invention is applied to provide an expansion valve, which comprises a valve seat, a valve sleeve and a valve needle, wherein a first end and a second end are respectively arranged at two ends of a cavity of the valve seat; 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, at least one part of the valve needle penetrates through the valve sleeve, and 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 circulation 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 an initial state; when the value that the fluid pressure in the first end is larger than the fluid pressure in the second end exceeds a preset range, the valve needle moves towards the direction far away from the valve sleeve so as to switch the throttling surface into an expansion state; when the fluid pressure in the second end is greater than the fluid pressure in the first end beyond a predetermined range, the valve sleeve moves in a direction away from the valve needle to switch the throttling surface to the expanded state. By adopting the scheme, when fluid flows along any direction in 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, throttling is realized, and the bidirectional flow of the expansion valve is realized. Compared with the existing expansion valve, the double-valve needle double-valve seat structure is not needed, the number of parts is simplified, and leakage points are reduced, so that the manufacturing cost can be reduced, and the using effect is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of an expansion valve provided in an embodiment of the present invention;

fig. 2 shows a schematic view of the expansion valve of fig. 1 in an open state;

FIG. 3 shows another schematic view of the expansion valve of FIG. 1 in an open state;

FIG. 4 shows a perspective view of FIG. 3;

figure 5 shows a first schematic view of the valve needle of figure 1;

figure 6 shows a cross-sectional view of the valve needle of figure 5;

figure 7 shows a second schematic view of the valve needle of figure 1;

figure 8 shows a cross-sectional view of the valve needle of figure 7;

figure 9 shows a third schematic view of the valve needle of figure 1;

figure 10 shows a cross-sectional view of the valve needle of figure 9;

fig. 11 shows a schematic view of the valve sleeve of fig. 1;

fig. 12 shows a cross-sectional view of the valve sleeve of fig. 11.

Wherein the figures include the following reference numerals:

10. a valve seat; 20. a valve housing; 21. a first jacket segment; 22. a second jacket segment; 30. a valve needle; 31. a base body; 32. a needle body; 33. a bevel; 34. a through hole; 41. a first elastic member; 42. a second elastic member; 51. a first positioning sleeve; 52. a second positioning sleeve; 60. and (6) taking over.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in the accompanying drawings, an embodiment of the present invention provides an expansion valve including: the valve seat 10 is provided with a cavity, and two ends of the cavity of the valve seat 10 are respectively a first end and a second end; a valve housing 20 disposed in the cavity of the valve seat 10, the valve housing 20 being movably disposed along an axial direction of the valve seat 10; a valve needle 30 disposed in 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-through cavity, the minimum section of the flow-through cavity along the radial direction of the valve seat 10 is a throttling surface, and the area of the throttling surface can be adjusted by the relative movement of the valve sleeve 20 and the valve needle 30; under the condition that the area of the throttling surface is zero, the first end and the second end are disconnected, and the expansion valve is in a closed state; under the condition that the area of the throttling surface is larger than zero, the first end is communicated with the second end, and the expansion valve is in an open state; when the pressure difference of the fluid in the first end and the fluid in the second end is within a preset range, the expansion valve is in a closed state; when the value of the fluid pressure in the first end being greater than the fluid pressure in the second end exceeds the 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 is switched to an open state; when the fluid pressure in the second end is greater than the fluid pressure in the first end beyond a predetermined range, the valve sleeve 20 is moved away from the valve needle 30 by the pressure difference to switch the expansion valve to the open state.

The technical scheme of the invention is applied to provide an expansion valve, the expansion valve comprises a valve seat 10, a valve sleeve 20 and a valve needle 30, and two ends of a cavity of the valve seat 10 are respectively a first end and a second end; the valve sleeve 20 is arranged in the cavity of the valve seat 10, and the valve sleeve 20 is movably arranged along the axial direction of the valve seat 10; the valve needle 30 is arranged in the cavity of the valve seat 10, at least one part of the valve needle 30 penetrates through the valve sleeve 20, and the valve needle 30 is movably arranged 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-through chamber; 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 an initial state; when the fluid pressure in the first end is greater than the fluid pressure in the second end beyond a predetermined range, the valve needle 30 moves away from the valve sleeve 20 to switch the throttle surface to the expanded state; when the fluid pressure in the second end is greater than the fluid pressure in the first end beyond a predetermined range, the valve sleeve 20 moves away from the valve needle 30 to switch the throttling surface to the expanded state. By adopting the scheme, when fluid flows along any one direction of two directions in the axial direction of the valve seat 10, the relative movement of the valve needle 30 and the valve sleeve 20 can be realized under the condition of meeting the pressure condition, so that the area of the throttling surface is increased, throttling and flow regulation are realized, and the bidirectional flow of the expansion valve is realized. Compared with the existing expansion valve, the double-valve needle double-valve seat structure is not needed, the number of parts is simplified, and leakage points are reduced, so that the manufacturing cost can be reduced, and the using effect is improved.

In particular, the flow-through chamber is a cavity in the axial direction of the valve seat 10, the valve sleeve 20 and the valve needle 30 being in the overlapping area. The valve sleeve 20 and the valve needle 30 are both actuated by a fluid pressure differential to effect relative movement therebetween. The area of the throttling surface in the initial state is zero or larger than zero, and the first end and the second end are communicated when the area of the throttling surface is larger than zero. In the present application, the area of the throttle surface in the initial state is larger than zero, i.e. the expansion valve still has a certain flow capacity, which reduces the noise of the applied equipment during the startup and shutdown.

In this embodiment, the valve seat 10 has a first step on the inner wall thereof for limiting the displacement of the valve sleeve 20 in the direction toward the valve needle 30, and the expansion valve further comprises: a first elastic member 41, one end of the first elastic member 41 abutting against one end of the valve sleeve 20 away from the needle 30. With the above arrangement, the valve sleeve 20 can be limited in two axial directions to limit the moving range of the valve sleeve 20.

In this embodiment, the valve sleeve 20 includes a first sleeve section 21 and a second sleeve section 22 that are connected to each other, an outer diameter of the first sleeve section 21 is greater than an outer diameter of the second sleeve section 22, at least a portion of the valve needle 30 is inserted into the second sleeve section 22, one side of the first sleeve section 21 abuts against the first elastic member 41, and the other side of the first sleeve section 21 is used for being in limit fit with the first step.

In this embodiment, the expansion valve further includes: the first positioning sleeve 51 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 elastic element 41 can be limited and guided by the first positioning sleeve 51.

Optionally, the first positioning sleeve 51 includes a first section, a second section and a third section, which are connected in sequence, the outer diameter of the first section is greater than the outer diameter of the second section, the inner diameter of the second section is greater than the inner diameter of the third section, the first elastic element 41 is inserted into the second section, the end of the first elastic element 41 is abutted against the third section, and the first section is riveted with the valve seat 10. Wherein the third section has an opening therein for fluid flow.

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 or inclined surface 33; in the case of a mutual distance of the valve sleeve 20 and the valve needle 30, the area of the throttle surface increases; in the case of a mutual approach of the valve sleeve 20 and the valve needle 30, the area of the throttle surface is reduced. With the above arrangement, as shown in fig. 1, when the pressure is high above, the valve needle 30 is pushed open by the pressure difference, and the throttle is realized by keeping a certain opening, and the larger the pressure difference is, the larger the downward opening of the valve needle 30 is, and the larger the flow capacity is. When the lower part is high pressure, the valve sleeve 20 is pushed open under the action of pressure difference, a certain opening degree is kept, throttling is realized, the larger the pressure difference is, the larger the upward opening degree of the valve sleeve 20 is, the larger the flow capacity is, and therefore the bidirectional flow regulation function is realized. When the pressure difference is small, the valve needle 30 and the valve sleeve 20 are positioned on the valve seat 10, and the area of the throttling surface is larger than zero at the moment, so that a certain flow capacity of the expansion valve at low pressure is ensured, and the fluid noise during the startup and shutdown is reduced.

In this embodiment, the valve needle 30 includes a seat 31 and a needle 32 connected to each other, the radial dimension of the seat 31 is larger than the radial dimension of the needle 32, at least a portion of the needle 32 penetrates through the valve housing 20, and the outer wall of the needle 32 has a tapered surface or inclined surface 33. The outer wall of the needle body 32 has a tapered surface or inclined surface 33, so that the area of the throttling surface can be changed when the needle body 32 and the valve sleeve 20 are displaced relatively, thereby realizing flow regulation. By adopting the scheme, the flow regulating device is simple in structure and convenient to realize accurate flow regulation. Specifically, the slope 33 is disposed obliquely with respect to the axis of the needle body 32.

In this embodiment, the seat body 31 has a through hole 34 therein, and the through hole 34 communicates the areas at the two ends of the seat body 31 in the cavity of the valve seat 10; and/or, a flow groove is arranged between the outer wall of the seat body 31 and the inner wall of the cavity of the valve seat 10, and the flow groove communicates the areas, which are positioned at the two ends of the seat body 31, in the cavity of the valve seat 10. Through the arrangement, the areas at the two ends of the seat body 31 can be communicated, so that the flow of fluid is realized.

Optionally, the seat body 31 includes a cylinder body and an end plate disposed at one end of the cylinder body, the needle body 32 is disposed on the end plate, an opening is disposed on a side wall of the cylinder body, one end of the opening is located on the end plate, and the other end of the opening is communicated with the cavity of the cylinder body. The opening in the side wall of the barrel and the cavity in the barrel form a through hole 34.

Optionally, the inner wall of the cavity of the valve seat 10 is cylindrical, the outer wall of the seat body 31 has a flat surface, and the area between the flat surface and the inner wall is a flow channel.

In this embodiment, the inner wall of the valve seat 10 has a second step for limiting a side of the seat body 31 facing the valve housing 20, and the expansion valve further includes: and a second elastic member 42, wherein one end of the second elastic member 42 is abutted against one end of the seat body 31 far away from the valve sleeve 20. With the above arrangement, the moving range of the valve needle 30 can be restricted by the second step and the second elastic member 42. Also, the second elastic member 42 may maintain the valve needle 30 at the initial position when the pressure is small.

In this embodiment, the expansion valve further includes: and a second positioning sleeve 52, wherein the second positioning sleeve 52 is connected with one end of the valve seat 10, and the other end of the second elastic member 42 is abutted against the second positioning sleeve 52. The second elastic element 42 can be limited and guided by the second positioning sleeve 52. Specifically, the second positioning sleeve 52 has the same structure as the first positioning sleeve.

In this embodiment, the expansion valve further includes: the adapter 60 is provided with the valve seat 10 inside the adapter 60, and the valve seat 10 is fixedly connected with the adapter 60. Fluid flow and connection to other lines is facilitated by the nipple 60.

Optionally, an annular groove is formed on the outer wall of the valve seat 10, and an annular protrusion is formed on the inner wall of the adapter 60, and the annular protrusion is clamped in the annular groove, so that the valve seat and the adapter are reliably connected.

In an embodiment not shown, the first positioning sleeve 51 or the second positioning sleeve 52 may be of an end cap type structure.

In an embodiment not shown, the valve housing 20 may be disposed within a first position sleeve 51, the first position sleeve 51 and the valve housing 20 being of unitary construction, and the valve needle 30 may be disposed within a second position sleeve 52, the second position sleeve 52 and the valve housing 20 being of unitary construction.

The technical scheme of the invention is applied to provide an expansion valve, the expansion valve comprises a valve seat 10, a valve sleeve 20 and a valve needle 30, and two ends of a cavity of the valve seat 10 are respectively a first end and a second end; the valve sleeve 20 is arranged in the cavity of the valve seat 10, and the valve sleeve 20 is movably arranged along the axial direction of the valve seat 10; the valve needle 30 is arranged in the cavity of the valve seat 10, at least one part of the valve needle 30 penetrates through the valve sleeve 20, and the valve needle 30 is movably arranged 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-through chamber; 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 an initial state; when the fluid pressure in the first end is greater than the fluid pressure in the second end beyond a predetermined range, the valve needle 30 moves away from the valve sleeve 20 to switch the throttle surface to the expanded state; when the fluid pressure in the second end is greater than the fluid pressure in the first end beyond a predetermined range, the valve sleeve 20 moves away from the valve needle 30 to switch the throttling surface to the expanded state. By adopting the scheme, when fluid flows along any direction in the axial direction of the valve seat 10, the relative movement of the valve needle 30 and the valve sleeve 20 can be realized under the condition of meeting the pressure condition, so that the area of a throttling surface is increased, throttling and flow regulation are realized, and the bidirectional flow of the expansion valve is realized. Compared with the existing expansion valve, the double-valve needle double-valve seat structure is not needed, the number of parts is simplified, and leakage points are reduced, so that the manufacturing cost can be reduced, and the using effect is improved.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.