An expansion valve

Abstract

This utility model discloses an expansion valve, including a valve body assembly. The valve body assembly includes a valve seat and a valve core. One end of the valve core is disposed within the valve seat, and a valve hole is formed on the valve core. The valve core includes a valve port section and a flow-retarding section. The valve port section forms the valve hole, and a first flow-retarding hole communicating with the valve hole is formed on the flow-retarding section. The expansion valve also includes a baffle plate disposed within the first flow-retarding hole. The baffle plate is opposite to and spaced apart from the valve hole, and the baffle plate can prevent liquid from flowing directly through the valve core along its axis. A noise reduction channel communicating with the first flow-retarding hole is provided on the side wall of the flow-retarding section. The noise reduction channel is located between the baffle plate and the valve hole, allowing liquid within the valve body assembly to flow between the valve hole, the first flow-retarding hole, and the noise reduction channel. This utility model can reduce noise during use.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, specifically to an expansion valve. Background Technology

[0002] The expansion valve is an important component in refrigeration and air conditioning systems, and its main function is to regulate the flow of refrigerant.

[0003] In existing expansion valves, the fluid directly enters or exits the throttling channel of the valve body. During cooling or heating, the fluid velocity in the expansion valve is too fast, which can easily generate turbulence and whistling noise during the flow process. This is especially true in the case of two-phase flow (gas and liquid mixing), where the uneven mixing of gas and liquid makes it easier to generate noise, which in turn affects the product quality of refrigeration equipment or air conditioners. Utility Model Content

[0004] This utility model aims to solve one of the technical problems in related technologies to a certain extent. To this end, this utility model provides an expansion valve with noise reduction and silencing effects.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: an expansion valve, comprising a valve body assembly, the valve body assembly comprising a valve seat and a valve core, one end of the valve core being disposed within the valve seat, a valve hole being formed on the valve core, the valve core comprising a valve port section and a flow-retarding section, the valve port section forming the valve hole, a first flow-retarding hole being formed on the flow-retarding section communicating with the valve hole, the expansion valve further comprising a baffle plate disposed within the first flow-retarding hole, the baffle plate being opposite to and spaced apart from the valve hole;

[0006] The side wall of the slow-flow section is provided with a noise reduction channel that communicates with the first slow-flow hole. The noise reduction channel is located between the baffle plate and the valve hole, and the liquid in the valve body assembly can flow between the valve hole, the first slow-flow hole and the noise reduction channel.

[0007] This technical solution, by setting up a baffle and a noise reduction channel, changes the flow direction of the liquid within the valve body assembly during use (so that the liquid does not flow directly through the valve hole along the axis completely). The change in the flow direction reduces the flow speed of the liquid, which can make the two-phase liquid mix more evenly, thereby reducing noise and improving product quality.

[0008] Furthermore, the axis of the noise reduction channel intersects the axis of the valve orifice.

[0009] Furthermore, the first flow-slowing orifice is coaxially arranged with the valve orifice, and the diameter of the first flow-slowing orifice is larger than the diameter of the valve orifice. The larger diameter of the first flow-slowing orifice and the abruptly enlarged flow cross-section can slow down the liquid flow and reduce noise.

[0010] Furthermore, a second flow-slowing orifice is formed at the end of the valve port section. The second flow-slowing orifice communicates with the valve port. The first and second flow-slowing orifices are respectively located at opposite ends of the valve port, and the diameter of the second flow-slowing orifice is larger than the diameter of the valve port. This allows for speed reduction and noise reduction of liquid flow in different directions within the valve body assembly.

[0011] Furthermore, the second slow-flow hole is formed as a tapered hole with an outer diameter larger than the inner diameter.

[0012] Furthermore, the baffle plate is provided with a through hole, which communicates with the first slow-flow hole, allowing the liquid in the valve body assembly to flow between the valve hole, the first slow-flow hole, and the through hole.

[0013] Furthermore, the number of noise reduction channels is set to multiple, and the multiple noise reduction channels are circumferentially distributed around the axis of the valve core.

[0014] Furthermore, the baffle is made of metal and is welded or riveted to the valve core.

[0015] Furthermore, a limiting platform is formed on the inner wall of the first slow-flow hole, the end face of the baffle plate is fitted with the limiting platform, and the outer wall of the baffle plate abuts against the inner wall of the first slow-flow hole.

[0016] Furthermore, the valve body assembly also includes a first connecting pipe and a second connecting pipe. The first connecting pipe is coaxially connected to the valve seat, and the second connecting pipe is connected to the side wall of the valve seat and communicates with the inner cavity of the valve seat. The valve core is disposed between the first connecting pipe and the second connecting pipe. The end of the valve port section is disposed inside the valve seat. The slow-flow section is disposed inside the first connecting pipe, and a gap is formed between the outer wall of the slow-flow section and the inner wall of the first connecting pipe.

[0017] Furthermore, the expansion valve also includes a valve needle, which is disposed on one side of the valve port section and opposite to the valve hole. The valve needle can move closer to or further away from the valve hole to adjust the opening degree of the expansion valve.

[0018] These features and advantages of this utility model will be disclosed in detail in the following specific embodiments and accompanying drawings. The preferred embodiments or means of this utility model will be shown in detail in conjunction with the accompanying drawings, but this is not intended to limit the technical solution of this utility model. In addition, each of these features, elements and components appearing in the following text and drawings is multiple and is labeled with different symbols or numbers for convenience, but all represent parts with the same or similar structure or function. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings:

[0020] Figure 1 This is a schematic cross-sectional view of the expansion valve according to one embodiment of the present invention;

[0021] Figure 2 for Figure 1 Enlarged view of point A (Schematic diagram of liquid cooling without through holes in the baffle);

[0022] Figure 3 This is a schematic diagram of the fluid flow at the valve core in one embodiment of the present invention (there is a through hole on the baffle plate);

[0023] Figure 4 This is a schematic diagram of the inclined arrangement of the noise reduction channel on the valve core in one embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the inclined arrangement of the noise reduction channel on the valve core in one embodiment of the present invention;

[0025] Figure 6 This is a front view schematic diagram of the valve core according to one embodiment of the present utility model;

[0026] Figure 7 This is a front view schematic diagram of the valve core according to one embodiment of the present utility model;

[0027] Figure 8 This is a top view of a baffle plate according to one embodiment of the present invention;

[0028] Figure 9 This is a top view of a baffle plate according to one embodiment of the present invention.

[0029] in,

[0030] 10. Valve body assembly; 11. Valve seat; 12. Valve core; 121. Valve port section; 1211. Valve hole; 1212. Second slow-flow hole; 122. Slow-flow section; 1221. First slow-flow hole; 1222. Noise reduction channel; 1223. Limiting platform;

[0031] 13. First connecting pipe; 14. Second connecting pipe;

[0032] 20. Baffle plate; 21. Through hole;

[0033] 30. Valve needle;

[0034] 40. Rotor assembly; 41. Magnetic rotor; 42. Guide rail shaft; 43. Slip ring; 44. Stop rod;

[0035] 50. Outer shell. Detailed Implementation

[0036] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described are intended to explain this utility model and should not be construed as limiting it.

[0037] The terms "an embodiment," "example," or "trademark" used in this specification refer to a particular feature, structure, or characteristic described in connection with the embodiment itself that may be included in at least one embodiment disclosed in this utility model. The phrase "in an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0038] See appendix Figure 1 , 2 One embodiment of this utility model discloses an expansion valve, including a valve body assembly 10. The valve body assembly 10 includes a valve seat 11 and a valve core 12. One end of the valve core 12 is disposed in the valve seat 11. A valve hole 1211 is formed on the valve core 12. The valve core 12 includes a valve port section 121 and a flow-retarding section 122. The valve port section 121 forms the valve hole 1211. A first flow-retarding hole 1221 is formed on the flow-retarding section 122, which communicates with the valve hole 1211. The expansion valve also includes a baffle plate 20 disposed in the first flow-retarding hole 1221. The baffle plate 20 is opposite to and spaced apart from the valve hole 1211.

[0039] The side wall of the slow-flow section 122 is provided with a noise reduction channel 1222 that communicates with the first slow-flow hole 1221. The noise reduction channel 1222 is located between the baffle plate 20 and the valve hole 1211. The liquid in the valve body assembly 10 can flow between the valve hole 1211, the first slow-flow hole 1221 and the noise reduction channel 1222.

[0040] The expansion valve in this embodiment generally also includes a rotor assembly 40, a valve needle 30, and a housing 50. The rotor assembly 40 includes a magnetic rotor 41, a guide shaft 42, a slip ring 43, a stop rod 44, etc. The housing 50 is fixedly connected to the valve seat 11. The rotor assembly 40 is disposed inside the housing 50. The guide shaft 42 and the valve needle 30 are connected by components such as springs and spring support seats. During use, the rotation of the magnetic rotor 41 drives the guide shaft 42 to rotate accordingly. The guide shaft 42 further drives the valve needle 30 to perform linear motion, thereby adjusting the opening degree of the expansion valve. The slip ring 43 is disposed on the guide shaft 42 through a spiral guide. The stop rod 44 is used to cooperate with the slip ring 43 to limit the start and stop positions of the linear motion of the guide shaft 42.

[0041] In actual production, the valve core 12 is generally welded and fixed inside the valve seat 11 (the valve core 12 can be partially or completely placed inside the valve seat 11). The valve core 12 is provided with a valve hole 1211 corresponding to the valve needle 30. The rotor assembly 40 drives the linear movement of the valve needle 30 to bring the valve needle 30 closer to (inserting) or away from the valve hole 1211.

[0042] In this embodiment, the rotor assembly 40 is used to communicate with the main control system of the refrigeration equipment or air conditioner when assembled with it, so as to automatically control the position of the valve needle 30 relative to the valve hole 1211, control the opening of the expansion valve, and achieve precise control of the flow of the expansion valve.

[0043] In this embodiment, the valve core 12 includes a valve port section 121 and a flow-retarding section 122, wherein the valve port section 121 and the flow-retarding section 122 are axially arranged, a valve hole 1211 is provided in the valve port section 121, and a first flow-retarding hole 1221 is formed in the flow-retarding section 122, as shown in the attached figure. Figure 2 As shown, the first slow-flow hole 1221 and the valve hole 1211 are interconnected. A baffle plate 20 is provided in the first slow-flow hole 1221. The baffle plate 20 prevents the liquid flow from directly passing through the valve core 12 axially. Thus, during the flow process, when the liquid reaches the baffle plate 20, its flow direction changes, and it flows through the noise reduction channel 1222 on the side wall of the valve core 12. (See attached diagram) Figure 2 , 3 Figure 4 shows a schematic diagram of the flow path of the liquid. It can be seen that when the liquid flows between the noise reduction channel 1222, the first slow-flow hole 1221 and the valve hole 1211, it will undergo multiple changes in flow direction. Each change in flow direction will slow down the flow rate, thereby reducing noise.

[0044] It should be noted that the function of the baffle plate 20 in this embodiment is to prevent the liquid flow from flowing directly through the valve core 12 along the axial direction. The blocking of the liquid flow mentioned here can be either to completely isolate the liquid flow from passing through the valve core 12 axially, so that the liquid flow can only pass through the valve core 12 through the noise reduction channel 1222, or to allow only part of the liquid flow to pass through the valve core 12 axially, while the other part flows through the noise reduction channel 1222. In this case, the baffle plate 20 has the effect of diverting the flow.

[0045] As can be seen, this embodiment does not specifically limit the structure of the baffle 20, as long as it can block the liquid flow and divert the liquid flow through the noise reduction channel 1222, thereby changing the direction of the liquid flow. Specifically, the baffle 20 can be configured to completely block the first slow-flow hole 1221, or it can be configured with a through hole 21 for liquid flow. In actual installation, the baffle 20 can completely isolate the fluid from passing through, or it can allow the fluid to pass through slowly (for example, the baffle 20 can be configured as a multi-layer filter structure).

[0046] Furthermore, this embodiment does not specifically limit the diameter relationship between the first slow flow orifice 1221 and the valve orifice 1211. In actual settings, the diameter of the first slow flow orifice 1221 can be set to be larger than the diameter of the valve orifice 1211, or in some cases it can be set to be equal to or smaller than the diameter of the valve orifice 1211.

[0047] This embodiment does not impose specific limitations on the size and location of the noise reduction channel 1222.

[0048] As one embodiment of this utility model, see the appendix. Figures 2 to 5 The axis of the noise reduction channel intersects the axis of the valve orifice.

[0049] This embodiment does not specify the angle between the noise reduction channel 1222 and the valve core 12 axis. In actual settings, the angle can generally be set between 45° and 90°. A 90° angle indicates that the axis of the noise reduction channel 1222 is orthogonal to the axis of the valve core 12. See Appendix. Figure 4 , 5 This is a schematic diagram showing the angle between the noise reduction channel 1222 and the axis of the valve core 12 being less than 90° and greater than 90°.

[0050] As one embodiment of this utility model, see the appendix. Figure 2 The first slow-flow hole 1221 is coaxially arranged with the valve hole 1211, and the diameter of the first slow-flow hole 1221 is larger than the diameter of the valve hole 1211.

[0051] In this embodiment, the diameter of the first slow-flow hole 1221 is larger than the diameter of the valve hole 1211. In this way, during the flow of the liquid, in addition to the deceleration and noise reduction effect caused by changing the flow direction of the liquid mentioned above, the flow cross section of the liquid after flowing through the noise reduction channel 1222 or the valve hole 1211 will suddenly expand, which can also slow down the speed of the liquid flow and achieve a better noise reduction effect, which is equivalent to forming a double noise reduction effect.

[0052] As one embodiment of this utility model, see the appendix. Figure 2 The valve port section 121 has a second slow flow hole 1212 formed at its end. The second slow flow hole 1212 communicates with the valve port 1211. The first slow flow hole 1221 and the second slow flow hole 1212 are respectively disposed at opposite ends of the valve port 1211. The diameter of the second slow flow hole 1212 is larger than the diameter of the valve port 1211.

[0053] In this embodiment, the valve core 12 has a first flow-retarding hole 1221 and a second flow-retarding hole 1212 respectively provided at both ends of the valve hole 1211. See Appendix. Figure 3When the liquid flows through the first slow-flow hole 1221, it will undergo the first speed reduction (the speed reduction principle is as described above). After the liquid flows through the valve hole 1211, it will enter the second slow-flow hole 1212. Since the diameter of the second slow-flow hole 1212 is larger than the diameter of the valve hole 1211, the flow cross section suddenly becomes larger, which can also reduce the speed of the liquid flow and further improve the noise reduction effect.

[0054] It should be noted that this description only describes the speed reduction effect of the fluid flow through valve core 12. For actual settings, please refer to the appendix. Figure 1 A larger cavity is formed inside the valve seat 11. After the liquid flows into this cavity, it also has a deceleration effect, which will not be elaborated here.

[0055] As one embodiment of this utility model, see the appendix. Figure 3 The second slow-flow hole 1212 is formed as a conical hole with an outer diameter larger than the inner diameter.

[0056] The design of the tapered structure of the second slow-flow hole 1212 in this embodiment can make the liquid flow more stable during the flow process, and also helps the valve needle 30 and valve core 12 to be installed and matched.

[0057] As one embodiment of this utility model, see the appendix. Figure 4 , 7 8. The baffle plate 20 is provided with a through hole 21, which communicates with the first slow flow hole 1221, and the liquid in the valve body assembly 10 can flow between the valve hole 1211, the first slow flow hole 1221 and the through hole 21.

[0058] In this embodiment, the baffle plate 20 is provided with a through hole 21. During use, the liquid coolant in the valve body assembly 10 passes through the baffle plate 20 and can pass through the through hole 21 on the baffle plate 20 to the valve core 12. That is, at this time, the liquid flow can pass through the valve core 12 through two different paths, as shown in the attached figure. Figure 3 As shown, in this embodiment, the liquid flow through the through hole 21 makes the distribution of the liquid flow in all directions more uniform when flowing through the valve core 12, so that the pressure of each part of the liquid flow is basically balanced, which helps to reduce noise.

[0059] In this embodiment, the distribution position of the through hole 21 on the baffle plate 20 is not specifically limited. In actual setting, the through hole 21 can be set at the center of the baffle plate 20, and the through hole 21 and the valve hole 1211 are coaxially set. The through hole 21 can also be set at a position away from the center of the baffle plate 20.

[0060] In addition, in actual setup, this embodiment does not specifically limit the number of through holes 21 on the baffle 20. In actual setup, the through holes 21 on the baffle 20 can be set to multiple, and the multiple through holes 21 can generally be evenly distributed on the baffle 20.

[0061] In one embodiment of this utility model, the number of noise reduction channels 1222 is set to multiple, and the multiple noise reduction channels 1222 are circumferentially distributed around the axis of the valve core 12.

[0062] In this embodiment, the noise reduction channel 1222 is circumferentially distributed around the axis of the valve core 12. In this way, during use, the liquid flow passes through the noise reduction channel 1222 from multiple different directions around the valve core 12, and the distribution of the liquid flow is more uniform, which helps to improve the stability of the liquid flow and reduce noise.

[0063] In this embodiment, the structure of multiple noise reduction channels 1222 can increase the flow area of ​​the fluid, thereby reducing the flow velocity. Of course, in actual settings, the number of noise reduction channels 1222 can be set to 3, 4, 5, 6, or even more, as shown in the attached figure. Figure 8 As shown, it can also be set to one; see appendix. Figure 9 For example, the design can be optimized based on the size of the valve core 12. If the diameters of the valve seat 11 and the valve core 12 are large, then a greater number of noise reduction channels 1222 can be set accordingly.

[0064] It should be noted that this embodiment does not specifically limit the shape of the noise reduction channel 1222. In actual settings, the noise reduction channel 1222 can be set as a rectangle, circle, triangle or irregular shape, as long as it can allow the liquid flow to pass through.

[0065] In one embodiment of this utility model, the baffle plate 20 is made of metal and is welded or riveted to the valve core 12.

[0066] In this embodiment, the baffle plate 20 is generally made of the same metal as the valve core 12, specifically stainless steel, copper, or other metals, which facilitates the welding and fixing of the baffle plate 20 and the valve core 12. Furthermore, in actual design, the baffle plate 20 and the valve core 12 can also be fixed by one or more methods such as riveting, snap-fitting, or necking, improving the stability of the fixing between the baffle plate 20 and the valve core 12.

[0067] In actual setup, the thickness of the baffle 20 can be set from 0.5mm to 2mm.

[0068] As one embodiment of this utility model, see the appendix. Figure 7A limiting platform 1223 is formed on the inner wall of the first slow-flow hole 1221. The end face of the baffle plate 20 is fitted to the limiting platform 1223, and the outer wall of the baffle plate 20 abuts against the inner wall of the first slow-flow hole 1221.

[0069] In this embodiment, the limiting platform 1223 provides an installation foundation and installation limit for the baffle plate 20 during installation, facilitating its installation. Furthermore, the surface fits between the limiting platform 1223 and the baffle plate 20, preventing tilting. The outer wall of the baffle plate 20 and the inner wall of the first slow-flow hole 1221 can abut against each other circumferentially, allowing for circumferential welding and improving the stability of the baffle plate 20 within the valve core 12.

[0070] As one embodiment of this utility model, see the appendix. Figure 1 The valve body assembly 10 further includes a first connecting pipe 13 and a second connecting pipe 14. The first connecting pipe 13 is coaxially connected to the valve seat 11, and the second connecting pipe 14 is connected to the side wall of the valve seat 11 and communicates with the inner cavity of the valve seat 11. The valve core 12 is disposed between the first connecting pipe 13 and the second connecting pipe 14. The end of the valve port section 121 is disposed inside the valve seat 11. The slow flow section 122 is disposed inside the first connecting pipe 13, and a gap is formed between the outer wall of the slow flow section 122 and the inner wall of the first connecting pipe 13.

[0071] In this embodiment, the first connecting pipe 13 and the second connecting pipe 14 can serve as the installation base for pipeline components in the equipment. The expansion valve of this utility model can be conveniently connected to the liquid flow pipeline in the equipment through the first connecting pipe 13 and the second connecting pipe 14.

[0072] The slow-flow section 122 of the valve core 12 can be set inside the first connecting pipe 13. In this embodiment, during the production of the expansion valve, the baffle plate 20 and the valve core 12 can generally be assembled in advance, and then the assembly of the valve core 12 and the baffle plate 20 can be installed together in the valve seat 11. Finally, the first connecting pipe 13 is sleeved on the outside of the valve core 12 and connected to the valve seat 11.

[0073] The expansion valve in this embodiment can be applied in air conditioning systems, refrigeration and freezing equipment, and heat pump systems in actual use.

[0074] The above are merely specific embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Those skilled in the art should understand that this utility model includes, but is not limited to, the contents described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of this utility model will be included within the scope of the claims.

Claims

1. An expansion valve, comprising a valve body assembly (10), the valve body assembly (10) including a valve seat (11) and a valve core (12), one end of the valve core (12) being disposed within the valve seat (11), and a valve hole (1211) being formed on the valve core (12), characterized in that, The valve core (12) includes a valve port section (121) and a slow-flow section (122). The valve port section (121) forms the valve hole (1211). The slow-flow section (122) forms a first slow-flow hole (1221) that communicates with the valve hole (1211). The expansion valve also includes a baffle plate (20) disposed in the first slow-flow hole (1221). The baffle plate (20) is opposite to and spaced apart from the valve hole (1211). The baffle plate (20) can prevent liquid from flowing directly through the valve core (12) along the axis of the valve core. The side wall of the slow-flow section (122) is provided with a noise reduction channel (1222) that communicates with the first slow-flow hole (1221). The noise reduction channel (1222) is located between the baffle plate (20) and the valve hole (1211). The liquid in the valve body assembly (10) flows between the valve hole (1211), the first slow-flow hole (1221) and the noise reduction channel (1222).

2. The expansion valve according to claim 1, characterized in that, The axis of the noise reduction channel (1222) intersects the axis of the valve hole (1211).

3. The expansion valve according to claim 1, characterized in that, The diameter of the first slow-flow orifice (1221) is larger than the diameter of the valve orifice (1211).

4. The expansion valve according to claim 3, characterized in that, A second slow-flow hole (1212) is formed at the end of the valve port section (121). The second slow-flow hole (1212) communicates with the valve hole (1211). The first slow-flow hole (1221) and the second slow-flow hole (1212) are respectively disposed at opposite ends of the valve hole (1211). The diameter of the second slow-flow hole (1212) is larger than the diameter of the valve hole (1211).

5. The expansion valve according to claim 4, characterized in that, The second slow-flow hole (1212) is formed as a tapered hole with an outer diameter larger than the inner diameter.

6. The expansion valve according to any one of claims 1 to 5, characterized in that, The baffle plate (20) is provided with a through hole (21), which communicates with the first slow flow hole (1221), and the liquid in the valve body assembly (10) can flow between the valve hole (1211), the first slow flow hole (1221) and the through hole (21).

7. The expansion valve according to any one of claims 1 to 5, characterized in that, The baffle plate (20) is made of metal and is welded or riveted to the valve core (12).

8. The expansion valve according to any one of claims 1 to 5, characterized in that, A limiting platform (1223) is formed on the inner wall of the first slow flow hole (1221). The end face of the baffle plate (20) is fitted with the end face of the limiting platform (1223). The outer wall of the baffle plate (20) abuts against the inner wall of the first slow flow hole (1221).

9. The expansion valve according to any one of claims 1 to 5, characterized in that, The valve body assembly (10) further includes a first connecting pipe (13) and a second connecting pipe (14). The first connecting pipe (13) is coaxially connected to the valve seat (11), and the second connecting pipe (14) is connected to the side wall of the valve seat (11) and communicates with the inner cavity of the valve seat (11). The valve core (12) is disposed between the first connecting pipe (13) and the second connecting pipe (14). The end of the valve port section (121) is disposed inside the valve seat (11). The slow flow section (122) is disposed inside the first connecting pipe (13), and a gap is formed between the outer wall of the slow flow section (122) and the inner wall of the first connecting pipe (13).

10. The expansion valve according to any one of claims 1 to 5, characterized in that, The expansion valve also includes a valve needle (30), which is disposed on one side of the valve port section (121) and opposite to the valve hole (1211). The valve needle (30) can move closer to or further away from the valve hole (1211) to adjust the opening of the expansion valve.

Images