A four-way reversing valve

Abstract

This invention discloses a four-way reversing valve, including a slider component and a valve seat. The valve seat includes a first valve port and a second valve port. The slider component includes a slider and a sealing portion that contacts the top end of the valve seat. The sealing portion includes a first side sealing portion with a first outer edge and a first pressure relief channel. The minimum distance between the first outer edge and the inner wall of the channel cavity is greater than the inner diameter of the first valve port. The four-way reversing valve provided in this application, by having a minimum distance between the first outer edge and the inner wall of the channel cavity greater than the inner diameter of the first valve port, and a minimum distance between the second outer edge and the inner wall of the channel cavity greater than the inner diameter of the second valve port, guides the refrigerant through the first and second pressure relief channels when the slider is in the intermediate position, thereby reducing the fluctuation amplitude of the intermediate flow and improving the reversing reliability of the four-way reversing valve.

Description

Technical Field

[0001] This invention relates to the field of refrigerant switching valves for refrigeration systems, and more specifically, to a four-way reversing valve. Background Technology

[0002] Figure 1 This is a cross-sectional schematic diagram of a four-way reversing valve in the background art. The four-way reversing valve includes a main valve body and a slider 2'. The main valve body includes a valve seat 1'. The upper end of the valve seat 1' contacts the sealing part of the slider 2'. The slider 2' can slide relative to the valve seat 1'. The four-way reversing valve realizes the switching of refrigerant flow direction by the position change between the slider 2' and the valve seat 1'. Summary of the Invention

[0003] Based on the four-way directional valve in the background technology, since the sealing part of the slider is smaller than the valve port diameter in the sliding direction, an intermediate channel is formed between the slider and the valve port of the valve seat during the sliding process, and the flow area of ​​the intermediate channel changes with the sliding of the slider. The inventors found that if the fluctuation of the intermediate flow is large, it will affect the directional valve efficiency.

[0004] This invention provides a four-way directional valve, including a slider component and a valve seat. The valve seat includes a first valve port and a second valve port. The slider component includes a slider and a sealing portion that contacts the top end of the valve seat. The sealing portion includes a first side sealing portion and a second side sealing portion. The first side sealing portion has a first outer edge and includes a first pressure relief channel. The valve chamber of the four-way directional valve includes a main valve chamber located outside the slider and a channel chamber located inside the slider. In the sliding direction of the slider, the first pressure relief channel extends from the first outer edge toward the channel chamber. Furthermore, the minimum distance between the first outer edge and the inner wall of the channel cavity is greater than the inner diameter of the first valve port; the second side sealing portion has a second outer edge and includes a second pressure relief channel. In the sliding direction of the slider, the second pressure relief channel extends from the second outer edge toward the channel cavity, and the minimum distance between the second outer edge and the inner wall of the channel cavity is greater than the inner diameter of the second valve port; during the sliding process of the slider, on the projection plane perpendicular to the sliding direction of the slider, the projection area of ​​the first pressure relief channel is equal, and the projection area of ​​the second pressure relief channel is equal.

[0005] The four-way reversing valve provided in this application has a minimum distance between the first outer edge and the inner wall of the channel cavity that is greater than the inner diameter of the first valve port, and a minimum distance between the second outer edge and the inner wall of the channel cavity that is greater than the inner diameter of the second valve port. When the slider is in the middle position, the refrigerant is guided through the first pressure relief channel and the second pressure relief channel, thereby reducing the fluctuation range of the intermediate flow and improving the reversing reliability of the four-way reversing valve. Attached Figure Description

[0006] Figure 1 Background Art: A cross-sectional schematic diagram of a four-way directional valve;

[0007] Figure 2 This invention provides a cross-sectional schematic diagram of the slider of a four-way reversing valve in the middle position;

[0008] Figure 3 : Figure 2 Enlarged view of point A in the middle;

[0009] Figure 4 : Figure 2 A cross-sectional view of the slider when it is in the exact center position;

[0010] Figure 5 : Figure 4 Enlarged view of point B in the middle;

[0011] Figure 6 : Figure 4 Enlarged view of point C in the middle;

[0012] Figure 7 : Figure 4 A schematic diagram of the refrigerant flow direction under the indicated conditions;

[0013] Figure 8 : Figure 7 Sectional view at point DD;

[0014] Figure 9 : Figure 2 The diagram shows the interaction between the slider and the valve seat of the four-way directional valve in the first reversing position.

[0015] Figure 10 : Figure 2 A schematic diagram of the intermediate flow curve of a four-way directional valve. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the accompanying drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The directional terms such as "up" and "down" used herein are... Figure 2 The positions of the components shown are defined only for clarity and convenience in expressing the technical solution. It should be understood that the directional terms used herein should not limit the scope of protection claimed in this application.

[0017] Figure 2A cross-sectional schematic diagram of a four-way reversing valve with the slider in the middle position, provided by the present invention; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 for Figure 2 A cross-sectional view of the slider when it is in the exact center position; Figure 5 for Figure 4 Enlarged view of point B in the middle; Figure 6 for Figure 4 Enlarged view of point C in the middle; Figure 7 for Figure 4 A schematic diagram of the refrigerant flow direction under the indicated conditions; Figure 8 for Figure 7 Sectional view at point DD; Figure 9 for Figure 2 The diagram shows a cross-sectional view of the sliding block and valve seat of the four-way directional valve in the first reversing position. Figure 10 for Figure 2 A schematic diagram of the intermediate flow curve of a four-way directional valve.

[0018] It should be noted that, with Figure 2 For example, the lateral direction of the four-way directional valve is the sliding direction of the slider 2 described below, and the longitudinal direction of the four-way directional valve is the direction perpendicular to the sliding direction of the slider 2 described below.

[0019] The four-way reversing valve of this embodiment includes a valve body component 1, a slider component, a valve seat 3, and a connecting pipe component 4. The valve body component 1 includes a main valve body 11, a first end cap 12, and a second end cap 13. The main valve body 11, the first end cap 12, and the second end cap 13 are made of stainless steel. The first end cap 12 and the second end cap 13 are formed by stamping. The first end cap 12 and the second end cap 13 are respectively welded and fixed to the ends of the main valve body 11 on the opposite side.

[0020] The valve seat 3 is welded and fixed to the inner wall of the main valve body 11. The valve seat 3 includes a first valve port 31, a second valve port 32, and an intermediate valve port 33. In the sliding direction of the slider 2, the intermediate valve port 33 is located between the first valve port 31 and the second valve port 32, and the first valve port 31, the second valve port 32, and the intermediate valve port 33 are generally evenly distributed along the sliding direction of the slider 2. The connecting pipe component 4 is made of stainless steel and includes an inlet connecting pipe 41, a first connecting pipe 42, an intermediate connecting pipe 43, and a second connecting pipe 44. The inlet connecting pipe 41 is connected to the main valve body 11, the first connecting pipe 42 is connected to the first valve port 31, the intermediate connecting pipe 43 is connected to the intermediate valve port 33, and the second connecting pipe 44 is connected to the second valve port 32.

[0021] The slider assembly includes a slider 2, a connecting rod 51, a first sealing bowl 52, and a second sealing bowl 53. In the sliding direction of the slider 2, the first sealing bowl 52 and the second sealing bowl 53 are respectively connected to the opposite ends of the connecting rod 51, with the middle portion of the connecting rod 51 connected to the slider 2. The slider 2 includes a sealing part 21, which contacts the top end 30 of the valve seat 3. When the four-way reversing valve reverses, when the slider 2 moves to the intermediate position (at this intermediate position, the first connecting pipe 42, the intermediate connecting pipe 43, and the second connecting pipe 44 are interconnected, forming an intermediate flow), the refrigerant in the four-way reversing valve will flow from the high-pressure side to the low-pressure side. The intermediate flow plays a pressure-relieving role during the reversing process, preventing the refrigeration system from being damaged by high pressure. The reversing of the four-way reversing valve is achieved by the pressure difference pushing the first sealing bowl 52 and the second sealing bowl 53, thereby switching the flow direction of the refrigerant in the four-way reversing valve.

[0022] In this embodiment, the sealing part 21 includes a first side sealing part 211 and a second side sealing part 212. The first side sealing part 211 has a first outer edge 2111 and includes a first pressure relief channel 2112. The valve chamber of the four-way reversing valve includes a main valve chamber 101 located outside the slider 2 and a channel chamber 201 located inside the slider 2. In the sliding direction of the slider 2, the first pressure relief channel 2112 extends from the first outer edge 2111 toward the channel chamber 201, and the second side sealing part 212 extends from the first outer edge 2111 toward the channel chamber 201. The minimum distance between the outer edge portion 2111 and the inner wall of the channel cavity 201 is greater than the inner diameter of the first valve port 31; the second side sealing portion 212 has a second outer edge portion 2121, and the second side sealing portion 212 includes a second pressure relief channel 2122. In the sliding direction of the slider 2, the second pressure relief channel 2122 extends from the second outer edge portion 2121 toward the channel cavity 201, and the minimum distance between the second outer edge portion 2121 and the inner wall of the channel cavity 201 is greater than the inner diameter of the second valve port 32. This reduces the fluctuation amplitude of the intermediate flow, thereby improving the switching reliability of the four-way directional valve.

[0023] It should be noted that during the switching process of the four-way directional valve, if the intermediate flow rate fluctuates significantly, the slider 2 may not be able to move smoothly to the predetermined position, resulting in an incomplete switching process or even no switching at all. Furthermore, fluctuations in the intermediate flow rate directly affect the pressure distribution within the refrigeration system. When the intermediate flow rate is too high, the pressure difference between the high-pressure and low-pressure sides within the valve chamber of the four-way directional valve may decrease, affecting the switching efficiency and consequently the normal operation of the refrigeration system. Conversely, if the intermediate flow rate is too low, the slider 2 may not be able to relieve pressure during switching, potentially causing damage to the refrigeration system due to high-pressure surges.

[0024] In this embodiment, during the sliding process of slider 2, the projected area of ​​the first pressure relief channel 2112 and the second pressure relief channel 2122 are equal on the projection surface perpendicular to the sliding direction of slider 2. Specifically, their projected shape is rectangular. Taking the first pressure relief channel 2112 as an example, the flow rate of refrigerant in the first pressure relief channel 2112 will remain uniform, avoiding flow fluctuations caused by changes in the cross-section of the first pressure relief channel 2112. This allows control over the fluctuation range of the intermediate flow rate and improves the switching reliability of the four-way reversing valve. This also simplifies the forming of the pressure relief channel and reduces the difficulty of the processing technology.

[0025] However, it should be noted that due to possible tolerances and errors in the actual processing, the projected area of ​​the first pressure relief channel 2112 may not be completely equal in actual manufacturing. Within a certain tolerance and error range, it is still equivalent to the concept of equal projected area in this embodiment.

[0026] like Figure 2-3 As shown, in the sliding direction of slider 2, the minimum distance between the first outer edge 2111 and the inner wall of the channel cavity 201 is defined as S1, and the inner diameter of the first valve port 31 is D1, then S1 > D1. Similarly, in the sliding direction of slider 2, the minimum distance between the second outer edge 2121 and the inner wall of the channel cavity 201 is defined as S2, and the inner diameter of the second valve port 32 is D2, then S2 > D2. Therefore, when the position of slider 2 changes, when slider 2 is in the middle position (as described below) Figure 3 Taking the first pressure relief channel 2112 as an example, the second pressure relief channel 2122 has the same function as the first pressure relief channel 2112 (and will not be elaborated here). In the longitudinal direction of the four-way reversing valve, the first side sealing part 211 is located above the first valve port 31, and the slider 2 is in the state of connecting the main valve chamber 101 with the first valve port 31. During the process of sliding to the state of closing the channel chamber 201 with the first valve port 31, the first side sealing part 211 always covers the first valve port 31 in the projection plane direction perpendicular to the sliding direction of the slider 2 (that is, in the longitudinal direction of the four-way reversing valve), ensuring that the refrigerant flows to the first valve port 31 through the first pressure relief channel 2112. That is, the magnitude of the intermediate flow is determined by the flow area of ​​the first pressure relief channel 2112. Therefore, the slider 2 can effectively control the intermediate flow to reduce the fluctuation amplitude of the intermediate flow of the four-way reversing valve, thereby improving the reversing reliability of the four-way reversing valve.

[0027] Based on the above, it should be further explained that the first side sealing part 211 has a first sealing surface 2114 that contacts the top end part 30, the first outer edge part 2111 includes a first chamfer part 2113, the lower end of the first chamfer part 2113 is connected to the sealing surface 2114, the wall part forming the channel cavity 201 includes a second chamfer part 2011, the lower end of the second chamfer part 2011 is connected to the sealing surface 2114, in the sliding direction of the slider 2, the distance between the lower end of the first chamfer part 2113 and the lower end of the second chamfer part 2011 is the aforementioned minimum distance S1, the medium can be guided by the first chamfer part 2113 and the second chamfer part 2011, which can improve the switching efficiency of the four-way reversing valve. Similarly, the second side sealing portion 212 has a second sealing surface 2124 that contacts the top end portion 30. The second side sealing portion 212 includes a third chamfered portion 2123, the lower end of which is connected to the second sealing surface 2124. In the sliding direction of the slider 2, the distance between the lower end of the third chamfered portion 2123 and the lower end of the second chamfered portion 2011 is the aforementioned minimum distance S2. The structure and function of the second side sealing portion 212 are the same as those of the first side sealing portion 211, and will not be described in detail here.

[0028] In this embodiment, the first valve port 31 includes a fourth chamfered portion 311, the upper end of which is connected to the top end portion 30. The maximum distance of the fourth chamfered portion 311 in the sliding direction of the slider 2 is the aforementioned inner diameter D1. Similarly, the second valve port 32 includes a fifth chamfered portion 321, the upper end of which is connected to the top end portion 30. The maximum distance of the fifth chamfered portion 321 in the sliding direction of the slider 2 is the aforementioned inner diameter D2. Likewise, the fourth chamfered portion 311 and the fifth chamfered portion 321 also have the function of guiding the medium, further improving the switching efficiency of the four-way directional valve.

[0029] like Figure 2-8 As shown, in the sliding direction of slider 2, the first pressure relief channel 2112 is at a first distance from the channel cavity 201. The first pressure relief channel 2112 is indirectly connected to the main valve cavity 101 and the channel cavity 201 through the first valve port 31. When slider 2 is in the middle position, the first pressure relief channel 2112 is connected to the main valve cavity 101 and the first valve port 31, and the first valve port 31 is connected to the channel cavity 201. In the sliding direction of slider 2, the second pressure relief channel 2121 is at a second distance from the channel cavity 201. The second pressure relief channel 2121 is indirectly connected to the main valve cavity 101 and the channel cavity 201 through the second valve port 32. When slider 2 is in the middle position, the second pressure relief channel 2121 is connected to the main valve cavity 101 and the second valve port 32, and the second valve port 32 is connected to the channel cavity 201. This ensures that the refrigerant is depressurized when the four-way reversing valve is in the middle reversing position, improving the reversing reliability of slider 2.

[0030] The four-way directional valve includes a first reversing position, a second reversing position, and an intermediate reversing position. The intermediate reversing position is located between the first and second reversing positions. The slider 2 includes a first position, a second position, and an intermediate position. When the slider 2 is in the first position, the four-way directional valve is in the first reversing position. Similarly, when the slider 2 is in the intermediate position, the four-way directional valve is in the intermediate reversing position. When the slider 2 is in the second position, the four-way directional valve is in the second reversing position. Under the action of the pressure difference, the slider 2 moves from the first reversing position (as shown in Figure 9) to the second reversing position, thus switching the flow direction of the four-way directional valve from communication between the first connecting pipe 42 and the intermediate connecting pipe 43 to communication between the second connecting pipe 44 and the intermediate connecting pipe 43. Figure 7 For example, it should be noted that during the sliding process of slider 2, the aforementioned intermediate position also includes the exact intermediate position. The minimum distance between the inner wall of the first valve port 31 and the inner wall of the channel cavity 201 is equal to the minimum distance between the inner wall of the second valve port 32 and the inner wall of the channel cavity 201. That is, when slider 2 is in the aforementioned exact intermediate position, the flow rate of the intermediate flow through the first valve port 31 to the channel cavity 201 is the same as the flow rate of the intermediate flow through the second valve port 32 to the channel cavity 201. When slider 2 is in the exact intermediate position, the flow direction of a portion of the refrigerant (which forms the intermediate flow) in the four-way reversing valve is as follows: Figure 7 As shown, the refrigerant in the main valve chamber 101 flows through the first pressure relief channel 2112 to the first valve port 31, and then through the first valve port 31 to the channel chamber 201, finally flowing to the intermediate valve port 33 to achieve pressure relief from the high-pressure side to the low-pressure side. Similarly, the refrigerant in the main valve chamber 101 flows through the second pressure relief channel 2212 to the second valve port 32, and then through the second valve port 32 to the channel chamber 201, finally flowing to the intermediate valve port 33 to achieve pressure relief from the high-pressure side to the low-pressure side.

[0031] like Figure 8 As shown, the first pressure relief channel 2112 is a first rectangular groove. On the projection plane perpendicular to the sliding direction of the slider 2, the longitudinal cross-sectional area of ​​the first rectangular groove serves as the projection area of ​​the first pressure relief channel 2112. The second pressure relief channel 2122 is a second rectangular groove. On the projection plane perpendicular to the sliding direction of the slider 2, the longitudinal cross-sectional area of ​​the second rectangular groove serves as the projection area of ​​the second pressure relief channel 2122. Of course, the cross-sectional shapes of the first pressure relief channel 2112 and the second pressure relief channel 2122 are not limited to this. Provided that the purpose of this invention is met, the longitudinal cross-sectional shapes of the first pressure relief channel 2112 and the second pressure relief channel 2122 can also be semi-circular, triangular, etc.

[0032] The first side sealing part 211 has a sealing surface 2114 that contacts the top part 30. In the direction perpendicular to the sliding direction of the slider 2, the first pressure relief channel 2112 is recessed upward from the sealing surface 2114, and the first pressure relief channel 2112 does not penetrate the upper end part 202 of the slider 2.

[0033] like Figure 7 As shown, the maximum distance between the first outer edge 2111 and the second outer edge 2121 in the sliding direction of slider 2 is defined as L1, and the maximum distance between the first valve port 31 and the second valve port 32 is defined as L2. Therefore, L1 > L2. This ensures that when slider 2 is in the middle region of valve seat 3 (i.e., when slider 2 is in the middle position), the flow path of the intermediate flow is always located between slider 2 and valve seat 3 through the aforementioned pressure relief channel, effectively controlling the fluctuation amplitude of the intermediate flow and thus ensuring the operational reliability of slider 2.

[0034] In this embodiment, such as Figure 8 As shown, the centerline of the slider 2 in the width direction is defined as Q, and the first pressure relief channel 2112 and the second pressure relief channel 2122 are distributed along the aforementioned centerline Q. This further shortens the flow path of the refrigerant, improves the switching efficiency of the four-way reversing valve, and facilitates the processing of the first pressure relief channel 2112 and the second pressure relief channel 2122.

[0035] In this embodiment, when slider 2 is in the intermediate position (i.e., the four-way directional valve is in the aforementioned intermediate reversing position), the flow area of ​​the first pressure relief channel 2112 is 0.8%-1.8% of the flow area of ​​the first valve port 31, and the flow area of ​​the second pressure relief channel 2212 is 0.8%-1.8% of the flow area of ​​the second valve port 32. This further controls the intermediate flow rate, thereby reducing the fluctuation amplitude of the intermediate flow rate of the four-way directional valve and improving the reversing reliability of the four-way directional valve.

[0036] The technical features of the above embodiments can be combined. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0037] The above examples illustrate the principles and implementation methods of the present invention. These embodiments are merely illustrative and intended to aid in understanding the method and core concepts of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the inventive concept, and these modifications also fall within the scope of protection of the present invention.

Claims

1. A four-way directional valve, characterized in that, The system includes a slider component and a valve seat (3). The valve seat (3) includes a first valve port (31) and a second valve port (32). The slider component includes a slider (2). The slider (2) includes a sealing portion (21). The sealing portion (21) contacts the top end (30) of the valve seat (3). The sealing portion (21) includes a first side sealing portion (211) and a second side sealing portion (212). The first side sealing portion (211) has a first outer edge portion (2111). The first side sealing portion (211) covers... The four-way reversing valve includes a first pressure relief channel (2112), and the valve chamber includes a main valve chamber (101) located outside the slider (2) and a channel chamber (201) located inside the slider (2). In the sliding direction of the slider (2), the first pressure relief channel (2112) extends from the first outer edge (2111) toward the channel chamber (201), and the minimum distance between the first outer edge (2111) and the inner wall of the channel chamber (201) is greater than the inner diameter of the first valve port (31). The second side sealing part (212) has a second outer edge part (2121) and includes a second pressure relief channel (2122). In the sliding direction of the slider (2), the second pressure relief channel (2122) extends from the second outer edge part (2121) toward the channel cavity (201), and the minimum distance between the second outer edge part (2121) and the inner wall of the channel cavity (201) is greater than the inner diameter of the second valve port (32). During the sliding process of the slider (2), on the projection surface perpendicular to the sliding direction of the slider (2), the projection surface area of ​​the first pressure relief channel (2112) is equal, and the projection surface area of ​​the second pressure relief channel (2122) is equal.

2. The four-way directional valve according to claim 1, characterized in that, In the sliding direction of the slider (2), the first pressure relief channel (2112) and the channel cavity (201) have a first distance. The slider (2) includes an intermediate position. When the slider (2) is in the intermediate position, the first pressure relief channel (2112) connects the main valve cavity (101) and the first valve port (31). The first valve port (31) connects the channel cavity (201). In the sliding direction of the slider (2), the second pressure relief channel (2121) and the channel cavity (201) have a second distance. When the slider (2) is in the middle position, the second pressure relief channel (2121) connects the main valve cavity (101) and the second valve port (32), and the second valve port (32) connects the channel cavity (201).

3. The four-way directional valve according to claim 1, characterized in that, The first pressure relief channel (2112) is a first rectangular groove. On the projection surface perpendicular to the sliding direction of the slider (2), the longitudinal cross-sectional area of ​​the first rectangular groove is used as the projection surface area of ​​the first pressure relief channel (2112). The second pressure relief channel (2122) is a second rectangular groove. On the projection surface perpendicular to the sliding direction of the slider (2), the longitudinal cross-sectional area of ​​the second rectangular groove is used as the projection surface area of ​​the second pressure relief channel (2122).

4. The four-way directional valve according to any one of claims 1-3, characterized in that, The valve seat (3) also includes an intermediate valve port (33), which is located between the first valve port (31) and the second valve port (32). It is defined that in the sliding direction of the slider (2), the maximum distance between the first outer edge (2111) and the second outer edge (2121) is L1, and the maximum distance between the first valve port (31) and the second valve port (32) is L2. Then, L1 > L2.

5. The four-way directional valve according to claim 4, characterized in that, Defined as Q, the centerline of the slider (2) in the width direction, and the first pressure relief channel (2112) and the second pressure relief channel (2122) are distributed along the centerline Q.

6. The four-way directional valve according to any one of claims 1-5, characterized in that, The slider (2) includes an intermediate position. When the slider (2) is in the intermediate position, the flow area of ​​the first pressure relief channel (2112) is 0.8%-1.8% of the flow area of ​​the first valve port (31), and the flow area of ​​the second pressure relief channel (2212) is 0.8%-1.8% of the flow area of ​​the second valve port (32).

7. The four-way directional valve according to any one of claims 1-5, characterized in that, The first side sealing portion (211) has a sealing surface (2114) that contacts the top end portion (30). The first outer edge portion (2111) includes a first chamfer portion (2113). The lower end of the first chamfer portion (2113) is connected to the sealing surface (2114). The wall portion forming the channel cavity (201) includes a second chamfer portion (2011). The lower end of the second chamfer portion (2011) is connected to the sealing surface (2114). In the sliding direction of the slider (2), the distance between the lower end of the first chamfer portion (2113) and the lower end of the second chamfer portion (2011) is the minimum distance between the first outer edge portion (2111) and the inner wall of the channel cavity (201). The second side sealing portion (212) has a second sealing surface (2124) that contacts the top end portion (30). The second side sealing portion (212) includes a third chamfer portion (2123). The lower end of the third chamfer portion (2123) is connected to the second sealing surface (2124). In the sliding direction of the slider (2), the distance between the lower end of the third chamfer portion (2123) and the lower end of the second chamfer portion (2011) is the minimum distance between the second outer edge portion (2121) and the inner wall of the channel cavity (201).

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