Sealing device

Abstract

To reduce manufacturing costs and secure stable sealability.SOLUTION: A sealing device 10 includes: an annular reinforcement ring 20 along an inner peripheral surface 111 of a hole of a housing 110; a cylindrical seal member 30 which is fixed to the reinforcement ring and formed of an elastic material; and an annular fixing member 40 along an outer peripheral surface of the seal member. The seal member includes: a first fixing part 31 which elastically deforms between the inner peripheral surface of the hole and the reinforcement ring to be fixed to the housing while tightly adhering to the inner peripheral surface of the hole; a second fixing part 32 which is fastened from the outer periphery side by the fixing member to be fixed to a shaft 120 while tightly adhering to an outer peripheral surface 121 of the shaft inserted into the hole of the housing; and a film part 33 provided between the first fixing part and the second fixing part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a sealing device.

Background Art

[0002] Conventionally, a sealing device for sealing an annular gap between a housing having a hole and a shaft inserted into the hole is known. For example, Patent Document 1 describes a joint seal in which a rubber-like elastic body is vulcanized and adhered to the outer peripheral surface of a cylindrical fitting inserted into an opening of a piping flow path. A seal lip that adheres to the inner peripheral surface of the piping flow path is provided on the rubber-like elastic body of this joint seal.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the joint seal described in Patent Document 1, since the seal lip is interposed between the outer peripheral surface of the cylindrical fitting and the inner peripheral surface of the piping flow path, the contact state between the seal lip and the inner peripheral surface of the piping flow path easily varies with the eccentricity of the cylindrical fitting. For this reason, in the joint seal described in Patent Document 1, it is necessary to increase the wall thickness (interference amount) of the seal lip so as to ensure the adhesion between the seal lip and the inner peripheral surface of the piping flow path.

[0005] Here, since the seal lip has an undercut shape, when the wall thickness of the seal lip increases, it becomes difficult to perform the ejection molding of the rubber-like elastic body. For this reason, it is necessary to provide a parting line extending in the direction crossing the seal lip, and as a result, a process for removing burrs and the like caused by the parting line is required.

[0006] In view of the above circumstances, an object of the present disclosure is to provide a sealing device that can reduce manufacturing costs while ensuring stable sealing performance.

Means for Solving the Problems

[0007] In order to solve the above problems, a sealing device according to an aspect of the present disclosure is a sealing device that seals an annular space formed between a housing having a hole and a shaft inserted into the hole, and includes an annular reinforcing ring along the inner peripheral surface of the hole, a cylindrical seal member fixed to the reinforcing ring and made of an elastic material, and an annular fixing member along the outer peripheral surface of the seal member. The seal member has a first fixing portion fixed to the housing in a state of being in close contact with the inner peripheral surface of the hole by elastically deforming between the inner peripheral surface of the hole and the reinforcing ring, a second fixing portion fixed to the shaft in a state of being in close contact with the outer peripheral surface of the shaft by being tightened from the outer peripheral side by the fixing member, and a film portion provided between the first fixing portion and the second fixing portion.

Advantages of the Invention

[0008] In the present disclosure, it is possible to provide a sealing device having stable sealing performance while reducing manufacturing costs.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0010] Hereinafter, preferred embodiments according to the present disclosure will be described with reference to the accompanying drawings. Note that the dimensions and scales of each part in the drawings are appropriately different from the actual ones, and there are also parts schematically shown for easy understanding. Further, the scope of the present disclosure is not limited to these embodiments unless otherwise specified in the following description.

[0011] 1-1. Sealing device FIG. 1 is a cross-sectional view of a sealing device 10 according to the first embodiment. The sealing device 10 seals an annular gap formed between a housing 110 having a hole H and a shaft 120 inserted into the hole H. The housing 110 and the shaft 120 are used, for example, in a connection structure or a joint provided in a machine such as an automobile, an industrial machine, or a construction machine, or an auxiliary machine thereof.

[0012] The housing 110 is a structure having a hole H. The housing 110 is made of, for example, a metal material such as iron, stainless steel, or aluminum alloy. The hole H is a space surrounded by an inner peripheral surface 111 along the axis AX1. Note that the material constituting the housing 110 is not limited to a metal material, and may be, for example, a resin material. Examples of the resin material include polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), and the like. The resin material may contain, if necessary, a fiber base material such as glass fiber, organic fiber, metal fiber, carbon fiber, or mineral fiber, or a particulate filler composed of a metal oxide such as alumina, a metal hydroxide such as aluminum hydroxide, or a nitride such as boron nitride.

[0013] In the example shown in FIG. 1, the housing 110 has a space S1 communicating with the hole H. The space S1 is a space surrounded by an inner peripheral surface 113 along the axis AX1. Here, the diameter of the inner peripheral surface 113 is smaller than the inner diameter Dh of the hole H. Therefore, a stepped surface 112 is provided between the inner peripheral surface 111 and the inner peripheral surface 113. The space S1 contains a fluid in a gaseous or liquid state. Examples of the fluid include a gas such as air, a liquid such as water or oil.

[0014] Note that the shape of the housing 110 only needs to be a shape having the hole H, and is not limited to the example shown in FIG. 1 and is arbitrary. For example, the diameter of the inner peripheral surface 113 may be equal to or larger than the inner diameter Dh of the hole H. Further, the shape of the inner peripheral surface 113 is not limited to a shape along a circle centered on the axis AX1 and is arbitrary. Furthermore, the space S1 may be provided as necessary and may be omitted.

[0015] The shaft 120 is a rod-shaped member having an outer peripheral surface 121 along the axis AX2. The shaft 120 is made of a metal material such as iron, stainless steel, or aluminum alloy, for example. The outer peripheral surface 121 has a smaller diameter than the inner peripheral surface 111 of the hole H of the housing 110 described above. For this reason, an annular space is formed between the outer peripheral surface 121 and the inner peripheral surface 111. Note that the material constituting the shaft 120 is not limited to a metal material and may be a resin material, for example. Examples of the resin material include polyetheretherketone (PEEK), polyphenylene sulfide (PPS), and polytetrafluoroethylene (PTFE). The resin material may contain a fiber base material such as glass fiber, organic fiber, metal fiber, carbon fiber, or mineral fiber as necessary, or may contain particulate fillers made of metal oxides such as alumina, metal hydroxides such as aluminum hydroxide, or nitrides such as boron nitride.

[0016] In the example shown in FIG. 1, the shaft 120 has a constant outer diameter Ds1 along the axis AX2. Further, the shaft 120 is a tubular body (hollow shaft) having a space S2. The space S2 is a space surrounded by an inner peripheral surface 122 along the axis AX2. The space S2 communicates with the space S1 and constitutes a flow path for the fluid described above, for example. Note that the shape of the shaft 120 is not limited to the example shown in FIG. 1 and may have a plurality of portions having different outer diameters, for example. Further, the shaft 120 may be a solid shaft.

[0017] In FIG. 1, a case where the axis AX1 and the axis AX2 coincide with each other is shown. Note that the axis AX1 and the axis AX2 do not necessarily coincide with each other, and one of the axis AX1 and the axis AX2 may be inclined with respect to the other. Further, the axis AX1 and the axis AX2 may change as the posture of the shaft 120 with respect to the housing 110 changes.

[0018] Hereinafter, the direction along the axis AX1 is referred to as the "axial direction", the direction orthogonal to the axis AX1 is referred to as the "radial direction", and the direction around the axis AX1 is referred to as the "circumferential direction". Further, the direction from the shaft 120 toward the housing 110 along the axis AX1 is referred to as the "X1 direction", and the direction opposite to the X1 direction is referred to as the "X2 direction". Note that, roughly speaking, since the axis AX1 and the axis AX2 coincide with each other, the direction along the axis AX2 may be defined as the "axial direction", the direction orthogonal to the axis AX2 may be defined as the "radial direction", and the direction around the axis AX2 may be defined as the "circumferential direction".

[0019] The sealing device 10 is a structure that seals an annular gap formed between the inner peripheral surface 111 of the hole H of the housing 110 and the outer peripheral surface 121 of the shaft 120. As shown in FIG. 1, the sealing device 10 includes a reinforcing ring 20, a seal member 30, and a fixing member 40.

[0020] The reinforcing ring 20 is an annular member that reinforces the seal member 30 along the axis AX1. The reinforcing ring 20 is disposed along the inner peripheral surface 111 of the hole H of the housing 110. The reinforcing ring 20 is made of a material having a higher Young's modulus than the material constituting the seal member 30 from the viewpoint of ensuring necessary rigidity and the like. Specifically, the reinforcing ring 20 is made of, for example, a resin material or a metal material.

[0021] Examples of the resin material constituting the reinforcing ring 20 include polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), and the like. The resin material may contain, as necessary, fiber base materials such as glass fiber, organic fiber, metal fiber, carbon fiber, or mineral fiber, or particulate fillers composed of metal oxides such as alumina, metal hydroxides such as aluminum hydroxide, or nitrides such as boron nitride. When the reinforcing ring 20 is made of a resin material, the reinforcing ring 20 is manufactured, for example, by injection molding.

[0022] Examples of the metal material constituting the reinforcing ring 20 include stainless steel or SPCC (cold-rolled steel). When the reinforcing ring 20 is made of a metal material, the reinforcing ring 20 is manufactured, for example, by pressing or forging.

[0023] When the reinforcing ring 20 is viewed in a cross-section cut along a plane including the axis AX1, it has an L shape. That is, the reinforcing ring 20 has a first portion 21 and a second portion 22. The first portion 21 has a cylindrical shape along the inner peripheral surface 111 of the hole H of the housing 110. The second portion 22 has a plate shape protruding radially inward from one end in the axial direction of the first portion 21. In the example shown in FIG. 1, the second portion 22 is connected to the end of the first portion 21 in the X1 direction and extends in a direction perpendicular to the axis AX1. Note that the cross-sectional shape of the reinforcing ring 20 is not limited to the example shown in FIG. 1, and may be a shape in which, for example, one of the first portion 21 and the second portion 22 is omitted.

[0024] Here, the outer diameter of the first portion 21 is smaller than the inner diameter Dh of the hole H. The inner diameter of the first portion 21 is larger than the outer diameter Ds1 of the shaft 120. Also, the inner diameter of the reinforcing ring 20 is larger than the inner diameter Ds2 of the shaft 120 and smaller than the outer diameter Ds1 of the shaft 120. Note that the inner diameter of the reinforcing ring 20 may be equal to or greater than the outer diameter Ds1 of the shaft 120, or may be equal to or less than the inner diameter Ds2 of the shaft 120.

[0025] The seal member 30 is a cylindrical elastic member that is fixed to the reinforcing ring 20 and is in close contact with the inner peripheral surface 111 of the hole H of the housing 110 and the outer peripheral surface 121 of the shaft 120, respectively. Here, the seal member 30 is fixed to the inner peripheral surface 111 together with the reinforcing ring 20 by press-fitting. Further, the shaft 120 is inserted inside the seal member 30.

[0026] The seal member 30 is made of an elastic material. Examples of the elastic material include rubber materials such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), or fluororubber (FKM). The seal member 30 is formed, for example, by insert molding with the reinforcing ring 20 as an insert. By this insert molding, a seal member 30 joined to the reinforcing ring 20 by vulcanization adhesion is obtained. Note that part or all of the seal member 30 may be made of a resin material such as a fluororesin such as PTFE (Poly Tetra Fluoro Ethylene). Further, the rubber material includes a material called an elastomer.

[0027] The rubber hardness of the rubber material constituting the seal member 30 is preferably 90° or less.

[0028] The seal member 30 has a first fixing portion 31, a second fixing portion 32, and a film portion 33. These are arranged side by side in the X1 direction in the order of the second fixing portion 32, the film portion 33, and the first fixing portion 31. Further, these are integrally formed of the aforementioned elastic material and are in close contact with the outer peripheral surface 121 of the shaft 120. Note that one or both of the first fixing portion 31 and the second fixing portion 32 do not have to be in close contact with the outer peripheral surface 121.

[0029] The first fixing portion 31 is an annular or cylindrical portion of the seal member 30 that is fixed to the inner peripheral surface 111 of the hole H of the housing 110. The first fixing portion 31 is joined to the reinforcing ring 20 by vulcanization adhesion or the like. In the example shown in FIG. 1, the first fixing portion 31 includes the reinforcing ring 20. That is, the reinforcing ring 20 is embedded in the first fixing portion 31.

[0030] The first fixing portion 31 is inserted into the hole H of the housing 110 with a predetermined tightening allowance. Therefore, the outer diameter of the first fixing portion 31 is slightly larger than the inner diameter Dh of the hole H of the housing 110 in a state where the first fixing portion 31 is not inserted into the hole H (natural state). When the first fixing portion 31 is inserted into the hole H, it elastically deforms between the inner peripheral surface 111 of the hole H and the reinforcing ring 20. Thereby, the first fixing portion 31 is fixed to the housing 110 in a state of being in close contact with the inner peripheral surface 111 of the hole H.

[0031] In the example shown in FIG. 1, a curved surface 31a is provided on the entire outer peripheral surface of the first fixing portion 31 over its entire circumference. The curved surface 31a has a convexly curved shape when viewed in a cross section cut by a plane including the axis AX1 or the axis AX2. For this reason, even if the posture of the first fixing portion 31 changes such that one of the axis AX1 and the axis AX2 is inclined with respect to the other, as long as the change is within a predetermined range, stable adhesion between the first fixing portion 31 and the inner peripheral surface 111 is ensured.

[0032] Further, the first fixing portion 31 has a portion 31b that protrudes inward from the outer peripheral surface 121 of the shaft 120. For this reason, the inner diameter D1 of the first fixing portion 31 is smaller than the outer diameter Ds1 of the shaft 120. The portion 31b overlaps the shaft 120 when viewed from the axial direction. For this reason, for example, when the first fixing portion 31 is inserted into the hole H by pushing the shaft 120 in the X1 direction with the seal member 30 attached to the shaft 120, the end 123 of the shaft 120 in the X1 direction is prevented from being located in the X1 direction with respect to the reinforcing ring 20. Also, the surface of the portion 31b facing the X2 direction contacts or is close to the end 123 of the shaft 120.

[0033] The thickness t1 of the first fixing portion 31 is determined in consideration of the aforementioned tightening allowance according to the difference between the inner diameter Dh of the hole H of the housing 110 and the outer diameter Ds1 of the shaft 120.

[0034] The second fixing portion 32 is an annular or cylindrical portion of the seal member 30 that is fixed to the outer peripheral surface 121 of the shaft 120. The second fixing portion 32 is tightened from the outer peripheral side by the fixing member 40. Thereby, the second fixing portion 32 is fixed to the shaft 120 in a state of being in close contact with the outer peripheral surface 121 of the shaft 120.

[0035] The thickness t2 of the second fixing portion 32 is thinner than the thickness t1 of the first fixing portion 31. For this reason, compared with a configuration in which the thickness t2 of the second fixing portion 32 is equal to or greater than the thickness t1 of the first fixing portion 31, the shaft 120 can be easily inserted inside the second fixing portion 32. Here, from the viewpoint of obtaining good adhesion between the second fixing portion 32 and the outer peripheral surface 121 of the shaft 120, the inner diameter of the second fixing portion 32 is preferably slightly smaller than the outer diameter Ds1 of the shaft 120 in a state where the shaft 120 is not inserted into the second fixing portion 32 (natural state). Note that the thickness t2 of the second fixing portion 32 is the thickness of a portion of the second fixing portion 32 where a protrusion 32a described later is not provided.

[0036] In the example shown in FIG. 1, a protrusion 32a that protrudes outward in the radial direction is provided at the end of the second fixing portion 32 in the X2 direction. For this reason, the durability of the second fixing portion 32 can be enhanced, and the fixing member 40 can be prevented from coming off from above the seal member 30. Note that the protrusion 32a may be provided as necessary, or may be omitted.

[0037] The film portion 33 is an annular or cylindrical portion of the seal member 30 that connects the first fixing portion 31 and the second fixing portion 32. The film portion 33 is provided between the first fixing portion 31 and the second fixing portion 32, and is connected to each of the end of the first fixing portion 31 in the X2 direction and the end of the second fixing portion 32 in the X1 direction.

[0038] The thickness t3 of the membrane portion 33 is thinner than the thickness t1 of the first fixing portion 31. For this reason, compared with a configuration in which the thickness t3 of the membrane portion 33 is equal to or greater than the thickness t1 of the first fixing portion 31, the membrane portion 33 can be deformed preferentially over the first fixing portion 31 as the posture of the shaft 120 with respect to the housing 110 changes. In the example shown in FIG. 1, the thickness t3 of the membrane portion 33 is equal to the thickness t2 of the second fixing portion 32. Note that the thickness t3 of the membrane portion 33 may be different from the thickness t2 of the second fixing portion 32.

[0039] The length L in the axial direction of the membrane portion 33 is not particularly limited, but from the viewpoint of preferably deforming the membrane portion 33, it is preferably equal to or greater than the thickness t2.

[0040] The fixing member 40 is an annular member for fixing the seal member 30 to the shaft 120. The fixing member 40 is, for example, a fastening member such as a resin or metal hose clip or band. The fixing member 40 is disposed along the outer peripheral surface of the seal member 30. Here, the second fixing portion 32 is interposed between the fixing member 40 and the outer peripheral surface 121 of the shaft 120. In that state, the fixing member 40 is tightened so that the second fixing portion 32 is in close contact with the outer peripheral surface 121.

[0041] FIG. 2 is a diagram for explaining the eccentricity of the shaft 120. In FIG. 2, a case where the axis AX2 is inclined at an angle θ with respect to the axis AX1 is shown. In this case, the membrane portion 33 deforms. For this reason, compared with a configuration without the membrane portion 33, the deformation and change in posture of the first fixing portion 31 are reduced. For this reason, even when the posture of the shaft 120 with respect to the housing 110 changes, stable adhesion between the first fixing portion 31 and the inner peripheral surface 111 of the hole H is ensured.

[0042] As described above, the sealing device 10 seals an annular space formed between a housing 110 having a hole H and a shaft 120 inserted into the hole H. Here, as described above, the sealing device 10 includes an annular reinforcing ring 20 along the inner peripheral surface 111 of the hole H, a cylindrical seal member 30 fixed to the reinforcing ring 20, and an annular fixing member 40 along the outer peripheral surface of the seal member 30. The seal member 30 is made of an elastic material as described above and has a first fixing portion 31, a second fixing portion 32, and a film portion 33. The first fixing portion 31 is fixed to the housing 110 in a state of being in close contact with the inner peripheral surface 111 of the hole H by elastically deforming between the inner peripheral surface 111 of the hole H and the reinforcing ring 20. The second fixing portion 32 is fixed to the shaft 120 in a state of being in close contact with the outer peripheral surface 121 of the shaft 120 by being tightened from the outer peripheral side by the fixing member 40. The film portion 33 is provided between the first fixing portion 31 and the second fixing portion 32.

[0043] In the above sealing device 10, since the first fixing portion 31 is in close contact with the inner peripheral surface 111 of the hole H and the second fixing portion 32 is in close contact with the outer peripheral surface 121 of the shaft 120, the annular space formed between the housing 110 and the shaft 120 can be sealed.

[0044] Moreover, since the film portion 33 is provided between the first fixing portion 31 and the second fixing portion 32, even if eccentricity of the shaft 120 with respect to the housing 110 occurs, by preferentially deforming the film portion 33 rather than the first fixing portion 31, a change in the posture of the first fixing portion 31 can be reduced. For this reason, the tightening allowance of the first fixing portion 31 can be made smaller than before. As a result, even when an undercut-shaped protrusion or the like is provided on the outer peripheral surface of the first fixing portion 31, the seal member 30 can be molded without providing a parting line that crosses the outer peripheral surface of the first fixing portion 31. As a result, stable adhesion between the first fixing portion 31 and the housing 110 can be ensured without performing a process of removing burrs or the like caused by the parting line.

[0045] In addition, since the tightening margin of the first fixing portion 31 can be made small, the insertion load of the first fixing portion 31 into the hole H of the housing 110 can be reduced, or the degree of freedom in the design of the first fixing portion 31 can be increased. For example, the width (fitting width) by which the first fixing portion 31 is in close contact with the housing 110 can be increased.

[0046] Furthermore, since the second fixing portion 32 is fixed to the shaft 120 by tightening with the fixing member 40, the second fixing portion 32 can be stably brought into close contact with the outer peripheral surface 121 of the shaft 120 regardless of the shape, surface roughness, and dimensional accuracy of the outer peripheral surface 121 of the shaft 120. Also, after the second fixing portion 32 is fixed to the shaft 120, the first fixing portion 31 can be inserted into the hole H of the housing 110. Therefore, the sealing device 10 can be easily assembled to the housing 110 and the shaft 120.

[0047] As can be understood from the above, in the sealing device 10, it is possible to ensure stable sealing performance while reducing the manufacturing cost.

[0048] In the present embodiment, as described above, the shaft 120 is a tubular body. Therefore, the internal space S2 of the shaft 120 can be communicated with the internal space S1 of the housing 110. As a result, a flow path can be formed by these spaces.

[0049] Also, as described above, the reinforcing ring 20 has a cylindrical first portion 21 and a plate-like second portion 22 that protrudes inward from one end in the axial direction of the first portion 21. Therefore, while securing the necessary width in the axial direction of the reinforcing ring 20, the rigidity in the radial direction of the reinforcing ring 20 can be efficiently increased. As a result, stable adhesion between the first fixing portion 31 and the inner peripheral surface 111 of the hole H of the housing 110 is obtained.

[0050] Furthermore, as described above, when the elastic material constituting the seal member 30 is a rubber material, the first fixing portion 31, the second fixing portion 32, and the film portion 33 are integrally formed of the rubber material. Therefore, the adhesion of the first fixing portion 31 to the housing 110 and the adhesion of the second fixing portion 32 to the shaft 120 can be enhanced respectively. Also, the film portion 33 can be easily deformed as the shaft 120 is eccentric with respect to the housing 110. Moreover, since the film portion 33 is integrally formed with the first fixing portion 31 and the second fixing portion 32, damage to the seal member 30 due to deformation of the film portion 33 can be reduced.

[0051] Here, when the rubber hardness of the rubber material constituting the seal member 30 is 90° or less, the film portion 33 can be easily deformed following the eccentricity of the shaft 120 with respect to the housing 110.

[0052] Also, as described above, when the reinforcing ring 20 is made of a metal material or a resin material, there is an advantage that it is easy to increase the rigidity of the reinforcing ring 20 in the radial direction.

[0053] Furthermore, as described above, the thickness of the film portion 33 is thinner than the thickness of the first fixing portion 31. Therefore, the film portion 33 can be easily deformed as the shaft 120 is eccentric with respect to the housing 110. Also, compared with the configuration where the thickness of the film portion 33 is equal to or greater than the thickness of the first fixing portion 31, deformation of the first fixing portion 31 due to deformation of the film portion 33 can be reduced. For this reason, even when the film portion 33 is deformed, the first fixing portion 31 can be stably adhered to the inner peripheral surface 111 of the hole H of the housing 110.

[0054] 2. Second Embodiment Hereinafter, a second embodiment of the present disclosure will be described. For elements whose actions and functions are the same as those in the above-described embodiments in the forms exemplified below, the reference numerals used in the description of the above-described embodiments will be reused and the detailed description of each will be omitted as appropriate.

[0055] Figure 3 is a cross-sectional view of the sealing device 10A according to the second embodiment. The sealing device 10A is configured in the same manner as the sealing device 10 of the first embodiment described above, except that it has a seal member 30A instead of the seal member 30. The seal member 30A is configured in the same manner as the seal member 30, except that it has a first fixing portion 31A instead of the first fixing portion 31. The first fixing portion 31A is configured in the same manner as the first fixing portion 31, except that it has an inclined surface 31c instead of the curved surface 31a. In FIG. 3, the shape of the first fixing portion 31A in the natural state is shown by a two-dot chain line.

[0056] The inclined surface 31c is provided on the outer peripheral surface of the first fixing portion 31A and is inclined so as to approach the axis AX1 or the axis AX2 as it goes toward the end of the first fixing portion 31A in the X1 direction. On the outer peripheral surface of the first fixing portion 31A shown in FIG. 3, an inclined surface is provided at a position in the X2 direction with respect to the inclined surface 31c, and the inclined surface is inclined so as to approach the axis AX1 or the axis AX2 as it goes toward the end of the first fixing portion 31A in the X2 direction. Instead of the inclined surface, a surface parallel to the axis AX1 or the axis AX2 may be provided.

[0057] Also with the above sealing device 10A, similar to the sealing device 10 of the first embodiment described above, it is possible to reduce the manufacturing cost while ensuring stable sealing performance. Further, in the present embodiment, as described above, the outer peripheral surface of the first fixing portion 31A has an inclined surface 31c that is inclined so that the thickness t1 becomes thinner as it goes in the direction away from the second fixing portion 32. Therefore, even when the shaft 120 is eccentric with respect to the housing 110, the first fixing portion 31A can be easily inserted into the hole H of the housing 110.

[0058] 3. Third Embodiment Hereinafter, a third embodiment of the present disclosure will be described. For elements whose operations and functions are the same as those of the above-described embodiments in the forms exemplified below, the reference numerals used in the description of the above-described embodiments are reused, and the detailed description of each is appropriately omitted.

[0059] FIG. 4 is a cross-sectional view of the sealing device 10B according to the third embodiment. The sealing device 10B is configured in the same manner as the sealing device 10 of the first embodiment described above, except that it has a seal member 30B instead of the seal member 30. The seal member 30B is configured in the same manner as the seal member 30, except that it has a first fixing portion 31B instead of the first fixing portion 31. The first fixing portion 31B is configured in the same manner as the first fixing portion 31A of the second embodiment, except that a lip portion 31d is added.

[0060] The lip portion 31d is a protrusion provided over the entire circumference of the outer peripheral surface of the first fixing portion 31B. In the example shown in FIG. 4, the lip portion 31d protrudes in a direction inclined with respect to the radial direction toward the outside in the radial direction. The tip (outer peripheral edge) of the lip portion 31d contacts the inner peripheral surface 111 of the hole H over the entire circumference. Note that the shape, position, size, etc. of the lip portion 31d are not limited to the example shown in FIG. 4 and are arbitrary. For example, the shape of the lip portion 31d may be a shape extending parallel to the radial direction or a shape extending parallel to the axial direction. Further, the lip portion 31d may contact the stepped surface 112. Also, the inclined surface 31c may be omitted.

[0061] Also with the above sealing device 10B, similar to the sealing device 10 of the first embodiment described above, it is possible to reduce the manufacturing cost while ensuring stable sealing performance. Further, in the present embodiment, as described above, the first fixing portion 31B has a lip portion 31d that contacts the inner peripheral surface 111 of the hole H over the entire circumference. Therefore, even when the machining accuracy of the hole H of the housing 110 is poor, the first fixing portion 31B can be stably adhered to the inner peripheral surface 111 of the hole H of the housing 110.

[0062] 4. Modifications Each of the embodiments illustrated above can be variously modified. Specific modification modes applicable to each of the above embodiments are illustrated below. Two or more modes arbitrarily selected from the following illustrations can be appropriately combined within a range where they do not conflict with each other.

[0063] 4-1. Modification 1 FIG. 5 is a cross-sectional view of the sealing devices 10_1 and 10_2 according to Modification 1. The sealing devices 10_1 and 10_2 are attached to both ends of the shaft 120. The sealing device 10_1 seals the annular space between the housing 110_1 and the shaft 120. The sealing device 10_2 seals the annular space between the housing 110_2 and the shaft 120. Here, each of the sealing devices 10_1 and 10_2 is configured in the same manner as the sealing device 10 of the first embodiment described above. Also, each of the housings 110_1 and 110_2 is configured in the same manner as the housing 110 of the first embodiment described above.

[0064] Note that the housings 110_1 and 110_2 may have different configurations from each other. Also, the sealing devices 10_1 and 10_2 may have different configurations from each other. Each of the sealing devices 10_1 and 10_2 may be configured in the same manner as the sealing device 10A of the second embodiment, or may be configured in the same manner as the sealing device 10B of the third embodiment.

[0065] 4-2. Modification 2 The shape of the first fixing portion of the seal member is not limited to the above-described embodiments. For example, the thickness of the first fixing portion may be constant in the axial direction.

Description of Reference Numerals

[0066] 10... sealing device, 10A... sealing device, 10B... sealing device, 10_1... sealing device, 10_2... sealing device, 20... reinforcing ring, 21... first portion, 22... second portion, 30... seal member, 30A... seal member, 30B... seal member, 31... first fixing portion, 31A... first fixing portion, 31B... first fixing portion, 31a... curved surface, 31b... portion, 31c... inclined surface, 31d... lip portion, 32... second fixing portion, 32a... protrusion, 33... film portion, 40... fixing member, 110... housing, 110_1... housing, 110_2... housing, 111... inner peripheral surface, 112... stepped surface, 113... inner peripheral surface, 120... shaft, 121... outer peripheral surface, 122... inner peripheral surface, 123... end, A... type, AX1... axis, AX2... axis, D1... inner diameter, Dh... inner diameter, Ds1... outer diameter, Ds2... inner diameter, H... hole, S1... space, S2... space, t1... thickness, t2... thickness, t3... thickness, θ... angle.

Claims

1. A sealing device for sealing an annular space formed between a housing having a hole and a shaft inserted into the hole, comprising: an annular reinforcing ring along the inner peripheral surface of the hole; a cylindrical seal member fixed to the reinforcing ring and made of an elastic material; an annular fixing member along the outer peripheral surface of the seal member, wherein the seal member has: a first fixing portion that is elastically deformed between the inner peripheral surface of the hole and the reinforcing ring and is fixed to the housing in a state of being in close contact with the inner peripheral surface of the hole; a second fixing portion that is fixed to the shaft in a state of being in close contact with the outer peripheral surface of the shaft by being tightened from the outer peripheral side by the fixing member; a film portion provided between the first fixing portion and the second fixing portion; wherein the first fixing portion is in close contact with the outer peripheral surface of the shaft; the first fixing portion has a portion protruding inward from the outer peripheral surface of the shaft; the portion is in contact with or close to the end of the shaft; the inner diameter of the reinforcing ring is smaller than the outer diameter of the shaft; a sealing device.

2. The shaft is a tubular body. The sealing device according to claim 1.

3. The reinforcing ring has a cylindrical first portion and a plate-like second portion protruding radially inward from one end of the first portion in the axial direction. The sealing device according to claim 1 or 2.

4. The elastic material is a rubber material. The first fixing portion, the second fixing portion, and the film portion are integrally formed of the rubber material. The sealing device according to any one of claims 1 to 3.

5. The rubber hardness of the rubber material is 90° or less. The sealing device according to claim 4.

6. The outer peripheral surface of the first fixing portion has an inclined surface that slopes so that the thickness decreases in a direction away from the second fixing portion. The sealing device according to any one of claims 1 to 5.

7. The reinforcing ring is made of a metal material or a resin material. The sealing device according to any one of claims 1 to 6.

8. The first fixing portion has a lip portion that contacts the inner peripheral surface of the hole over the entire circumference. The sealing device according to any one of claims 1 to 7.

9. The thickness of the film portion is thinner than the thickness of the first fixing portion. The sealing device according to any one of claims 1 to 8.

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