Seal member

Abstract

To provide a seal member capable of reducing sliding resistance.SOLUTION: The seal member 1 includes a main body portion 10 formed of an elastic material having an inner peripheral surface 11 and an outer peripheral surface 12 which are a pair of surfaces facing away from each other, and a resistance reduction layer 20 which is a member provided on at least a part of the inner peripheral surface 11 which is one of the pair of surfaces of the main body portion 10. The main body portion 10 has a plurality of through holes 13.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a seal member, and more particularly to a seal member used in a flow path switching valve. [Background technology]

[0002] Rotary flow path switching valves have been used to switch the flow path of a fluid flowing, for example, in an automobile engine compartment. Some of these conventional flow path switching valves include a valve body that defines a valve chamber therein and has a flow path communicating with the valve chamber, and a valve disc that rotates within the valve chamber to switch the flow path. These flow path switching valves are provided with a seal member to seal the flow path connected by the valve disc. The seal member is a cylindrical member made of an elastic material and has a through hole corresponding to the flow path. The seal member is provided in an annular gap between the rotor of the valve disc and the valve body within the valve chamber, and seals the gap between the rotor and the valve body so as to seal the flow path selected by the rotor of the valve disc. Furthermore, the rotating rotor slides on the inner peripheral surface of the seal member (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-034560 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described flow path switching valve, the rotor slides on the inner peripheral surface of the seal member, causing friction between the rotor and the seal member, and a frictional force is applied to the rotor. This frictional force becomes resistance to the sliding of the rotor (sliding resistance), and the sliding resistance becomes resistance to the rotational drive of the valve disc. For this reason, there has traditionally been a demand for a configuration that reduces sliding resistance in seal members used in flow path switching valves.

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a seal member that can reduce sliding resistance. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the sealing member of the present invention is a sealing member for sealing a flow path between a valve body and a valve main body in a flow path switching valve, and comprises a main body portion formed from an elastic material having a pair of surfaces facing each other, and a resistance reduction layer which is a member provided on one of the pair of surfaces of the main body portion, wherein the main body portion has a plurality of through holes, the resistance reduction layer is formed by coating, and the resistance reduction layer is formed so as to protrude in the direction facing the one surface.

[0007] In a sealing member according to one embodiment of the present invention, a plurality of convex portions, which are portions that form protruding portions, are formed on one surface, and the resistance reduction layer is formed on at least the plurality of convex portions.

[0008] In a sealing member according to one embodiment of the present invention, the other of the pair of surfaces is the surface facing the valve body, and the resistance reduction layer is formed on the portion facing away from the portion where the other of the pair of surfaces contacts the valve body.

[0009] In one embodiment of the sealing member of the present invention, the other of the pair of surfaces has a plurality of lip portions which are portions that protrude from the other of the pair of surfaces and surround each of the plurality of through holes, and the plurality of lip portions are configured to contact the valve body.

[0010] In the sealing member according to one aspect of the present invention, a plurality of the resistance reducing layers are formed, and the plurality of resistance reducing layers are formed on the plurality of convex portions.

[0011] In the sealing member according to one aspect of the present invention, the resistance-reducing layer is formed on the entire one surface.

[0012] In a seal member according to one aspect of the present invention, a plurality of the resistance reducing layers are formed, and the plurality of resistance reducing layers extend along the plurality of lip portions, respectively.

[0013] In the sealing member according to one aspect of the present invention, the resistance-reducing layer is formed by applying a liquid material.

[0014] In a sealing member according to one aspect of the present invention, the resistance reducing layer is disposed in the plurality of through holes.

[0015] In a sealing member according to one aspect of the present invention, the resistance reduction layer passes through the plurality of through holes and reaches the other of the pair of surfaces.

[0016] In the seal member according to one aspect of the present invention, the main body portion is cylindrical.

[0017] In the seal member according to one aspect of the present invention, the main body portion is plate-shaped. [Effects of the Invention]

[0018] The sealing member according to the present invention can reduce sliding resistance. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view schematically showing the configuration of an example of a flow path switching valve to which a seal member according to the present invention is applied. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] 1 is a perspective view showing a schematic configuration of a sealing member according to an embodiment of the present invention. [Figure 4] 1 is a front view showing a schematic configuration of a sealing member according to an embodiment of the present invention. [Figure 5] FIG. 2 is a transparent front view of a seal member according to an embodiment of the present invention, showing the inner circumferential side thereof. [Figure 6] 1 is a cross-sectional view showing a schematic configuration of a sealing member according to an embodiment of the present invention. [Figure 7] 1 is a cross-sectional view of a specific example of a sealing member according to an embodiment of the present invention. [Figure 8] 1 is a cross-sectional view of a specific example of a sealing member according to an embodiment of the present invention. [Figure 9] 1 is a perspective view showing a schematic configuration of a specific example of a sealing member according to an embodiment of the present invention. [Figure 10] 1 is a perspective view showing a schematic configuration of a specific example of a sealing member according to an embodiment of the present invention. [Figure 11] FIG. 12 is a cross-sectional view showing a schematic configuration of the seal member shown in FIG. [Figure 12] 1 is a perspective view showing a schematic configuration of a specific example of a sealing member according to an embodiment of the present invention. [Figure 13] 13 is a cross-sectional view schematically illustrating a cross section of a portion of the seal member shown in FIG. 12. FIG. [Figure 14] 1 is a cross-sectional view schematically illustrating a cross section of a portion of one specific example of a sealing member according to an embodiment of the present invention. [Figure 15] 15 is a cross-sectional view schematically showing a cross section of a modified example of the sealing member shown in FIG. 14. FIG. [Figure 16] 1 is a perspective view showing a schematic configuration of a specific example of a sealing member according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. A sealing member according to the present invention is a sealing member for sealing a flow path between a valve element and a valve main body in a flow path switching valve. FIGS. 1 and 2 are cross-sectional views schematically showing the configuration of a flow path switching valve 100 as an example of a flow path switching valve to which the sealing member according to the present invention is applied. FIG. 2 is a cross-sectional view showing a cross section taken along line AA in FIG. 1. The flow path switching valve 100 is a multi-control valve that switches the flow path of a circulating coolant to control the flow of the coolant in a vehicle equipped with an electric motor, such as an electric vehicle (EV). The flow path switching valve 100 switches the flow path of the coolant to change the module through which the coolant flows.

[0021] 1 and 2, the flow path switching valve 100 has a valve body 110 in which a valve chamber 111 is formed, and a valve element 120 rotatably supported by the valve body 110. The seal member according to the present invention is attached to the annular space between the valve element 110 and the valve body 110 within the valve chamber 111. As an example of the seal member according to the present invention, a seal member 1 according to an embodiment of the present invention, which will be described later, is shown in FIGS.

[0022] As shown in FIG. 1, the valve body 110 has a cylindrical base 112 and a cover 113. A valve chamber 111 is defined inside the base 112. The valve body 110 defines a cylindrical space extending along the axis x1 of the valve disc 120, and this space forms the valve chamber 111. As shown in FIGS. 1 and 2, cylindrical outflow ports 114 and 115 are connected to the sides of the base 112, and the outflow ports 114 and 115 form flow paths 114a and 115a, respectively, that penetrate the base 112 and communicate with the valve chamber 111. An opening 112a that opens the valve chamber 111 in the direction of the axis x1 is formed in the bottom of the base 112, and a through-hole 116 extending along the axis x1 is formed in the upper part of the base 112. The through-hole 116 forms an opening in the upper surface 112b of the base 112, communicates with the valve chamber 111, and penetrates the valve body 110 at its upper part in the direction of the axis x1. The upper surface 112a is an annular surface that defines the upper end of the valve chamber 111.

[0023] 1, the cover 113 of the valve body 110 has a lid portion 113a that closes the opening 112a of the base 112, and the lid portion 113a is fitted into the opening 112a to close the opening 112a. The lid portion 113a is fixed to the base 112, for example, by adhesive. In this manner, the lid portion 113a of the cover 113 closes the space formed in the valve body 110 and, together with the base 112 of the valve body 110, defines the valve chamber 111. The cover 113 also has a cylindrical inlet port 117 that is connected to the lid 113a. The inlet port 117 forms a flow path 117a that passes through the lid 113a and communicates with the valve chamber 111.

[0024] 1 and 2, the valve element 120 has a shaft portion 121 connected to the output shaft of a motor (not shown) and a rotor 122 that switches between the flow paths 114a and 115a within the valve chamber 111. The rotor 122 is a cylindrical portion with a bottom, and has a cylindrical cylindrical portion 123 and an upper end portion 124 that closes the cylindrical portion 123 at its upper end. The upper end portion 124 is in slidable contact with the upper surface 112a of the base 112. Furthermore, the lower end surface 123b of the cylindrical portion 123 is in slidable contact with the lid portion 113a of the cover 113. The outer peripheral side surface 123a of the cylindrical portion 123 faces the side surface 112b that defines the side end of the valve chamber 111 of the base 112 of the valve body 110, at a constant or approximately constant radial distance. Two through holes 125 and 126 are formed in the cylindrical portion 123 of the rotor 122, and as shown in FIG. 2, the two through holes 125 and 126 are positioned relative to each other so as to be able to communicate with the flow paths 114a and 115a, respectively.

[0025] 1, the lower end of the shaft 121 is connected to the upper end 124 of the rotor 122, and the upper end of the shaft 121 passes through a through-hole 116 in the valve body 110, with the shaft 121 protruding from the valve body 110. The shaft 121 is in slidable contact with the through-hole 116. An annular groove 121a is formed in the shaft 121, and an O-ring 127 is fitted in the groove 121a to seal the gap between the shaft 121 and the valve body 110 at the through-hole 116.

[0026] 1 and 2, the seal member 1 is provided in the valve chamber 111 in an annular gap between a side surface 123a of the cylindrical portion 123 of the rotor 122 of the valve element 120 and a side surface 112b of the base 112 of the valve body 110. The seal member 1 is fixed to the valve body 110, and relative movement with respect to the valve body 110 is suppressed. The seal member 1 is compressed in the radial direction by the side surface 123a of the cylindrical portion 123 of the rotor 122 and the side surface 112b of the base 112 of the valve body 110, thereby sealing the flow path formed in the flow path switching valve 100.

[0027] As the shaft portion 121 of the valve element 120 rotates about the axis x1, the positions of the through holes 125, 126 of the rotor 122 rotate about the axis x1. This rotational movement switches the flow path that communicates with the flow path 117a of the inlet port 117 between the flow path 114a of the outlet port 114 and the flow path 115a of the outlet port 115 via the internal space of the rotor 122. When the shaft portion 121 rotates and the rotor 122 rotates, the side surface 123a of the cylindrical portion 123 of the rotor 122 slides against the inner circumferential surface of the seal member 1.

[0028] Fig. 3 is a perspective view showing a schematic configuration of a seal member 1 according to an embodiment of the present invention, and Fig. 4 is a front view showing a schematic configuration of the seal member 1. Fig. 5 is a see-through front view of the seal member 1 showing the inner peripheral side, and Fig. 6 is a cross-sectional view of the seal member 1. Note that in the drawings, not all of the multiple components are assigned reference numerals, and the reference numerals of some of the multiple components may be omitted.

[0029] As shown in Figures 3 to 6, the seal member 1 includes a main body 10 made of an elastic material and having a pair of surfaces, an inner circumferential surface 11 and an outer circumferential surface 12, facing each other, and a resistance-reducing layer 20 provided on at least a portion of the inner circumferential surface 11, one of the pair of surfaces of the main body 10. The main body 10 has a plurality of through holes 13. The resistance-reducing layer 20 is formed by coating. The configuration of the seal member 1 will be described in detail below.

[0030] As shown in FIGS. 3 to 6 , the main body 10 has, for example, a cylindrical shape. Specifically, for example, it has a cylindrical or approximately cylindrical shape with the axis x as its central axis or approximate central axis. The inner circumferential surface 11 is a cylindrical surface facing the inner circumferential side and extends, for example, on a cylindrical surface or approximately cylindrical surface with the axis x as its central axis or approximate central axis. The outer circumferential surface 12 is a surface facing away from the inner circumferential surface 11 in the radial direction and is a cylindrical surface facing the outer circumferential side and extends, for example, on a cylindrical surface or approximately cylindrical surface with the axis x as its central axis or approximate central axis. The through-holes 13 penetrate the main body 10 in the radial direction and form openings on the inner circumferential surface 11 and the outer circumferential surface 12. The multiple through-holes 13 are formed to communicate with flow paths 114 a and 115 a formed in the valve main body 110 of the flow path switching valve 100. For example, as shown in Figures 3 to 5, the multiple through holes 13 are arranged in two annular rows around the axis x aligned in the axis x direction, and in each row, the multiple through holes 13 are arranged at equal or approximately equal angular intervals around the axis x. Note that the arrangement of the multiple through holes 13 is not limited to this. As shown in Figures 4 and 5, each through hole 13 is, for example, rectangular. Note that the shape of each through hole 13 is not limited to this.

[0031] As shown in FIG. 4, the outer peripheral surface 12 of the main body 10 is formed with a plurality of lip portions 14 protruding from the outer peripheral surface 12. The plurality of lip portions 14 surround the plurality of through holes 13, respectively. That is, each through hole 13 is located in a region of the outer peripheral surface 12 surrounded by the lip portion 14. Also, for example, as shown in FIG. 4, each through hole 13 is surrounded by a plurality of lip portions 14 in multiple layers. Note that each through hole 13 may be surrounded by a single layer of lip portions. For example, as shown in FIG. 4, the plurality of lip portions 14 each include a plurality of vertical lip portions 15 that are lip portions 14 extending along the axis x, and a plurality of horizontal lip portions 16 that are lip portions 14 that extend in the circumferential direction perpendicular or substantially perpendicular to the vertical lip portions 15.

[0032] As described above, the main body 10 is made of an elastic material, and examples of the elastic material that forms the main body 10 include rubber and thermoplastic elastomer (TPE). However, the elastic material that forms the main body 10 is not limited to these, and various elastic materials can be used.

[0033] 5 and 6, the entire inner circumferential surface 11 of the main body 10 is covered with a resistance-reducing layer 20. The resistance-reducing layer 20 is formed by coating. The resistance-reducing layer 20 has low friction and wear resistance, and in the flow path switching valve 100, it can reduce the sliding resistance of the rotor 122 to the cylindrical portion 123 and also make the seal member 1 less susceptible to wear due to friction with the cylindrical portion 123 of the rotor 122.

[0034] The material of the resistance-reducing layer 20 is, for example, a material with excellent lubricity, specifically, a liquid material containing a component with excellent lubricity, such as fluorine, silicon, graphite, etc. However, the material of the resistance-reducing layer 20 is not limited to these, and various materials with excellent lubricity can be used.

[0035] The coating for forming the resistance-reducing layer 20 may be applied by, for example, using a spray or a dispenser, or by dipping, etc. However, the coating for forming the resistance-reducing layer 20 is not limited to these.

[0036] The resistance-reducing layer 20 is formed by coating, which reduces manufacturing costs compared to conventional methods of forming a PTFE layer by baking. Furthermore, because the resistance-reducing layer 20 is formed by coating, it can be formed on the inner circumferential surface 11 of the main body 10 in various shapes, which improves the degree of freedom in forming the resistance-reducing layer 20 on the inner circumferential surface 11 of the main body 10 compared to conventional methods.

[0037] The rigidity of the resistance reduction layer 20 can be adjusted by changing the material and thickness of the resistance reduction layer 20. This makes it possible to adjust the friction coefficient and wear resistance, and also to adjust the ease of assembly of the seal member 1 into the valve chamber 111 of the valve body 110 of the flow path switching valve 100.

[0038] The seal member 1 has the above-described configuration and is provided in the annular gap between the side surface 123a of the cylindrical portion 123 of the rotor 122 and the side surface 112b of the base 112 of the valve body 110 in the valve chamber 111, as described above. In the valve chamber 111, the seal member 1 presses the multiple lip portions 14 against the side surface 112b of the base 112, thereby sealing the flow path formed by the through hole 13 of the seal member 1 and the flow paths 114a, 115a of the valve body 110 that communicate with the through hole 13. In addition, the side surface 123a of the cylindrical portion 123 of the rotor 122 comes into contact with the entire resistance-reducing layer 20 of the seal member 1, thereby sealing the flow path formed by the through hole 13 of the seal member 1 and the through holes 125, 126 of the rotor 122 that communicate with the through hole 13. In addition, since the cylindrical portion 123 of the rotor 122 is in contact with the low-friction resistance reduction layer 20, the sliding resistance of the rotor 122 against the cylindrical portion 123 is reduced, and the torque required to rotate the valve body 110 can be reduced.

[0039] As described above, according to the seal member 1 according to the embodiment of the present invention, the sliding resistance to the valve body 120 can be reduced.

[0040] Next, a specific example of the seal member 1 will be described.

[0041] Regarding the above-described seal member 1, FIG. 7 is a cross-sectional view showing one specific example of the seal member 1, and FIG. 8 is a cross-sectional view showing another specific example of the seal member 1. Note that FIGS. 7 and 8 show cross sections along the axis x near the through holes 13 of the main body 10. As shown in FIG. 7, the resistance-reducing layer 20 may be present in any or all of the multiple through holes 13. Also, as shown in FIG. 8, the resistance-reducing layer 20 may pass through any or all of the multiple through holes 13 and reach the outer peripheral surface 12 of the main body 10. Note that, as shown in FIGS. 7 and 8, within the through hole 13, the resistance-reducing layer 20 is attached to the inner peripheral surface 13a of the through hole, which is an annular surface that defines the through hole 13.

[0042] Furthermore, the resistance reducing layer 20 may be formed so as to protrude in the direction facing the inner circumferential surface 11 (toward the inner circumferential side). For example, the resistance reducing layer 20 may be formed on a part of the inner circumferential surface 11 of the main body 10. For example, the resistance reducing layer 20 may be formed intermittently in the direction of the axis x and in the circumferential direction. Specifically, for example, as shown in FIG. 9 , the resistance reducing layer 20a may be formed intermittently along the axis x on each of the vertical surface portions 11a, which are portions of the inner circumferential surface 11 extending along the axis x, and the resistance reducing layer 20b may be formed intermittently along the circumferential direction on each of the horizontal surface portions 11b, which are portions of the inner circumferential surface 11 extending along the circumferential direction.

[0043] Alternatively, the resistance-reducing layer 20 may be formed in an annular shape only on the surface of the inner circumferential surface 11 of the main body 10 that faces away from the lip portion 14. In this case, in the flow path switching valve 100, the resistance-reducing layer 20 is formed on the portion of the inner circumferential surface 11 that protrudes inward when the lip portion 14 contacts the side surface 112b of the base 112 of the valve body 110, and the resistance-reducing layer 20 can be formed only on the portion that contacts the side surface 123a of the tubular portion 123 of the rotor 122. Specifically, for example, as shown in FIGS. 10 and 11 , the resistance-reducing layer 20a that protrudes inward has the same or substantially the same shape as the vertical lip portion 15 is formed on the portion of the inner circumferential surface 11 that faces away from each vertical lip portion 15 on the inside in the radial direction, and the resistance-reducing layer 20b that protrudes inward has the same or substantially the same shape as the horizontal lip portion 16 is formed on the portion of the inner circumferential surface 11 that faces away from each horizontal lip portion 16 on the inside in the radial direction. The resistance reduction layer 20a extends along the axis x, similar to the vertical lip portions 15. Similarly to the horizontal lip portions 16, the resistance reduction layer 20b extends in the circumferential direction perpendicular or substantially perpendicular to the resistance reduction layer 20a. It is not necessary for all vertical lip portions 15 to be provided with the resistance reduction layer 20a; there may be vertical lip portions 15 on which the resistance reduction layer 20a is not formed on the radially inner, opposing portion of the inner circumferential surface 11. In other words, the number of resistance reduction layers 20a does not have to be the same as the number of vertical lip portions 15, and may be less than the number of vertical lip portions 15. Furthermore, the number of resistance reduction layers 20a may be greater than the number of vertical lip portions 15. Similarly, it is not necessary for all horizontal lip portions 16 to be provided with the resistance reduction layer 20b; there may be horizontal lip portions 16 on which the resistance reduction layer 20b is not formed on the radially inner, opposing portion of the inner circumferential surface 11. That is, the number of resistance reducing layers 20b does not have to be the same as the number of lateral lip portions 16, and may be less than the number of lateral lip portions 16. Also, the number of resistance reducing layers 20b may be more than the number of lateral lip portions 16.

[0044] 10 and 11 , in the flow path switching valve 100, the vertical lip portion 15 and the horizontal lip portion 16 contact the side surface 112b of the base 112 of the valve body 110, respectively, and thereby resistance-reducing layers 20a, 20b are formed on the portion of the inner circumferential surface 11 that protrudes inward, and the resistance-reducing layers 20a, 20b can be formed on the portion that contacts the side surface 123a of the cylindrical portion 123 of the rotor 122 or on the portion that strongly contacts the side surface 123a. This reduces the contact area of ​​the inner circumferential surface 11 with the side surface 123a of the cylindrical portion 123 of the rotor 122. This effectively reduces the sliding resistance of the seal member 1 against the valve disc 120.

[0045] 12 and 13, a plurality of protrusions 11c protruding inward may be formed on the inner circumferential surface 11, and a resistance-reducing layer 20 may be formed on each of the protrusions 11c. FIG. 13 is a cross-sectional view of the protrusions 11c. FIG. 13 shows, for example, a cross-section of the protrusions 11c taken along a plane including the axis x and a portion of the main body 10. As shown in FIG. 13, the resistance-reducing layer 20 is formed on the apex 11ca of the protrusions 11c and in the vicinity of the apex 11ca. The apex 11ca of the protrusions 11c is the radially innermost portion of the protrusions 11c. The shape of the protrusions 11c is not limited to a hemispherical or substantially hemispherical shape as shown in FIGS. 12 and 13, and may be other shapes. For example, the shape of the protrusions 11c may be other shapes, such as a conical or approximately conical surface, a pyramidal or approximately pyramidal surface, a truncated conical or approximately truncated conical surface, etc. Furthermore, the protrusions 11c are not limited to being uniformly or approximately uniformly spaced apart over the entire inner circumferential surface 11 as shown in FIG. 12. For example, the protrusions 11c may be unevenly spaced over the inner circumferential surface 11, or may be provided only on a part of the inner circumferential surface 11, for example, only on the vertical surface portion 11a or only on the horizontal surface portion 11b. The arrangement of the protrusions 11c is not limited to this.

[0046] 12 and 13, in the flow path switching valve 100, the inner circumferential surface 11 contacts the side surface 123a of the cylindrical portion 123 of the rotor 122 at the protruding portion 11c via the resistance-reducing layer 20. This reduces the contact area of ​​the inner circumferential surface 11 with the side surface 123a of the cylindrical portion 123 of the rotor 122. This effectively reduces the sliding resistance of the seal member 1 against the valve body 120.

[0047] 14, a plurality of protrusions 11c protruding inward may be formed on the inner circumferential surface 11, and the resistance-reducing layer 20 may be formed on the inner circumferential surface 11 so as to cover the entire inner circumferential surface 11, including the protrusions 11c. FIG. 14 is a cross-sectional view showing a portion of the main body 10 including the protrusions 11c. FIG. 14 shows, for example, a cross-section of the protrusions 11c taken along a plane including the axis x. As shown in FIG. 14, in this specific example, the shape of the protrusions 11c is a truncated cone or a substantially truncated cone. As with the above-described cases shown in FIGS. 12 and 13, the shape of the protrusions 11c is not limited to the illustrated shape. As shown in FIG. 14, the resistance-reducing layer 20 is embedded between adjacent protrusions 11c. This makes the resistance-reducing layer 20 less likely to peel off from the inner circumferential surface 11. 15, when the shape of the protrusions 11c is wider on the inner circumferential side than on the outer circumferential side, the resistance-reducing layer 20 can be made less likely to peel off from the inner circumferential surface 11. The protrusions 11c are formed, for example, so that the inner circumferential side is wider in the circumferential direction and in the direction of the axis x than on the outer circumferential side. Also, the protrusions 11c are formed, for example, so that the inner circumferential side is wider in the circumferential direction or in the direction of the axis x than on the outer circumferential side. The shape of the protrusions 11c is not limited to these shapes.

[0048] Furthermore, the resistance-reducing layer 20 may be formed not only on the inner peripheral surface 11 of the main body 10 but also on the outer peripheral surface 12 of the main body 10, or may be formed on the entire surface of the main body 10. When the resistance-reducing layer 20 is formed not only on the inner peripheral surface 11 of the main body 10 but also on the outer peripheral surface 12, the sealing member 1 can be made reversible. Furthermore, by providing the resistance-reducing layer 20 on the outer peripheral surface 12 of the main body 10, the sealing member 1 can be easily attached to the valve chamber 111 of the valve body 110.

[0049] Specifically, for example, as shown in FIG. 16 , a resistance-reducing layer 21 similar to the resistance-reducing layer 20 may also be formed on the outer peripheral surface 12 of the main body 10. That is, a part or the entire outer peripheral surface 12 may be covered with the resistance-reducing layer 21. In this case, for example, the thickness of the resistance-reducing layer 21 may be set so that the portion covering the lip portion 14 protrudes outward more than the portion covering the portion of the outer peripheral surface 12 that is not the lip portion 14. Alternatively, the thickness of the resistance-reducing layer 21 may be set so that the portion covering the lip portion 14 does not protrude outward more than the portion covering the portion of the outer peripheral surface 12 that is not the lip portion 14, and the entire portion covering the outer peripheral surface 12 has a smooth surface. Alternatively, the resistance-reducing layer 21 may be formed to cover only the lip portion 14. For example, the resistance-reducing layer 21 may be formed on each of the plurality of lip portions 14 on the outer peripheral surface 12 of the main body 10 so as to cover the tip of each of the plurality of lip portions 14. Furthermore, the lip portion 14 may be formed on the outer peripheral surface 12 of the main body portion 10 by the resistance reducing layer 21 instead of being formed integrally with the main body portion 10 .

[0050] Furthermore, the sealing member 1 may be in the form of a plate or sheet that extends in a plane, rather than in the form of a cylinder as described above. For example, the sealing member 1 may be in the form of a rectangular plate or sheet. In this case, by rolling the sealing member 1 into a cylinder, it can be used in the flow path switching valve 100 in the same way as the above-described cylindrical sealing member 1, and in this case too, it exhibits the same effect as the above-described cylindrical sealing member 1.

[0051] The resistance-reducing layers 20, 21 may be formed on the main body 10, for example, by attaching the main body 10 to a member having a shape that imitates the cylindrical portion 123 of the rotor 122 of the valve body 120. When the main body 10 is plate-shaped or sheet-shaped as in the above-described modified example, the main body 10 is wrapped around a member having a shape that imitates the cylindrical portion 123 of the rotor 122 of the valve body 120, and the resistance-reducing layers 20, 21 are formed on the main body 10 in this state.

[0052] It should be noted that each of the above-described modifications may be combined with other modifications.

[0053] Although the present invention has been described above through the above embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0054] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. Furthermore, the above-described embodiments do not limit the scope of the present invention, and the present invention may include any and all applications. The components of the above-described embodiments, as well as their arrangement, materials, conditions, shape, size, etc., are not limited to those illustrated and may be modified as appropriate. For example, the present invention includes differences that arise during implementation due to manufacturing tolerances, etc. Furthermore, components illustrated in different embodiments may be partially substituted or combined within the scope of technical inconsistency. Furthermore, the various configurations may be selectively combined as appropriate to achieve at least some of the above-described problems and effects. [Explanation of symbols]

[0055] 1 seal member, 10 main body portion, 11 inner peripheral surface, 11a vertical surface portion, 11b horizontal surface portion, 11c convex portion, 11ca top portion, 12 outer peripheral surface, 13 through hole, 13a through hole inner peripheral surface, 14 lip portion, 15 vertical lip portion, 16 horizontal lip portion, 20, 20a, 20b, 21 resistance reduction layer, 100 flow path switching valve, 110 valve body, 111 valve chamber, 112 base body, 112a upper surface, 112b side surface, 113 cover, 113a lid portion, 114, 115 outflow port, 114a, 115a flow path, 116 through hole, 117 inflow port, 117a flow path, 120 valve body, 121 shaft portion, 122 rotor, 123 cylindrical portion, 123a Side, 124 Top, 125,126 Through hole, x,x1 axis

Claims

1. A seal member for sealing a flow path between a valve element and a valve body in a flow path switching valve, a main body portion formed of an elastic material and having a pair of surfaces facing each other; a resistance reducing layer that is a member provided on one of the pair of surfaces of the main body portion, The main body portion has a plurality of through holes, the resistance-reducing layer is formed by coating, the resistance reducing layer is formed so as to protrude in a direction in which the one surface faces, Sealing material.

2. A plurality of convex portions that form the protruding portion are formed on the one surface, The resistance reducing layer is formed on at least the plurality of protrusions. The seal member according to claim 1 .

3. the other of the pair of surfaces is a surface facing the valve body, The resistance-reducing layer is formed on a portion of the other of the pair of surfaces facing away from a portion where the other of the pair of surfaces contacts the valve body. The seal member according to claim 1 .

4. the other of the pair of surfaces has a plurality of lip portions that are portions that protrude from the other of the pair of surfaces and surround the plurality of through holes, The plurality of lip portions are adapted to contact the valve body. The sealing member according to claim 1 or 3.

5. A plurality of the resistance reducing layers are formed, the plurality of resistance reducing layers are formed on the plurality of convex portions, The seal member according to claim 2 .

6. the resistance reducing layer is formed on the entire one surface, The seal member according to claim 2 .

7. A plurality of the resistance reducing layers are formed, The plurality of resistance reducing layers extend along the plurality of lip portions, respectively. The sealing member according to claim 4 dependent on claim 3.

8. The resistance reducing layer is formed by applying a liquid material. The seal member according to claim 1 .

9. The resistance reducing layer is disposed in the plurality of through holes. The seal member according to claim 1 .

10. the resistance reduction layer passes through the plurality of through holes and reaches the other of the pair of surfaces; The seal member according to claim 1 .

11. The main body is cylindrical. The seal member according to claim 1 .

12. The main body is plate-shaped. The seal member according to claim 1 .

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