Sealing device

Abstract

The utility model provides a sealing device which does not need a large occupied space and is low in cost. A sealing device (1) is provided with: a holding member (2) having an annular shape about an axis (x); an annular member (3) made of a fluororesin material, the annular member (3) being held by the holding member (3) and extending toward the inner peripheral side (IC); and an elastic body part (4) covering at least the outer peripheral side (OC) of the holding member (2).

Description

Technical Field

[0001] The utility model relates to a sealing device. Background Art

[0002] For example, Chinese Patent Application Publication No. 116447138 discloses a sealing structure of a hydrogen circulation pump incorporated in a hydrogen fuel cell. Utility Model Content

[0003] Problems to be solved by the utility model

[0004] This sealing structure has a complicated structure, and therefore requires a large occupied space and is costly.

[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 low-cost sealing device which does not require a large occupied space.

[0006] Means used to solve problems

[0007] In order to achieve the above-mentioned purpose, the sealing device involved in the utility model includes: a retaining component, which is annular with an axis as the center; an annular component made of fluororesin material, which is retained by the retaining component and extends toward the inner peripheral side; and an elastic body portion, which covers at least the outer peripheral side of the retaining component.

[0008] In the sealing device involved in the utility model, the fluororesin material is PTFE.

[0009] In the sealing device involved in the present invention, the retaining component includes: an outer retaining component, which is annular with the axis as the center; and an inner retaining component, which is annular with the axis as the center and is embedded in the inner circumference of the outer retaining component, and the annular component is sandwiched between the outer retaining component and the inner retaining component in the axial direction.

[0010] In the sealing device according to the present invention, the elastic body portion includes: a radial cover covering the outer peripheral surface of the outer holding member; and an axial cover covering the side surface of the outer holding member.

[0011] In the sealing device according to the present invention, the holding member is formed of stainless steel.

[0012] The utility model relates to a hydrogen circulation pump for a hydrogen fuel cell, comprising: a rotating shaft, which rotates around an axis; a shell, which has a through hole for inserting the rotating shaft; and a sealing device, which seals between the rotating shaft and the through hole, and the sealing device comprises: a retaining component, which is annular with the axis as the center; an annular component, which is made of fluororesin material, the annular component is retained by the retaining component and extends toward the inner circumference to contact the rotating shaft; and an elastic body, which covers at least the outer circumference of the retaining component and is sandwiched between the retaining component and the shell.

[0013] Utility Model Effect

[0014] According to the utility model, a low-cost sealing device which does not require a large occupied space can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a cross-sectional view schematically showing the structure of a sealing device 1 according to one embodiment of the present invention.

[0016] Figure 2 This is an enlarged cross-sectional view in one direction of the sealing device 1 schematically showing the structure of the sealing device 1 according to one embodiment of the present invention.

[0017] Figure 3 It is a cross-sectional view schematically showing the structure of a hydrogen circulation pump 50 to which the sealing device 1 is applied.

[0018] Figure 4 This is a cross-sectional view showing a usage state of the sealing device 1 according to one embodiment of the present invention. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a cross-sectional view schematically showing the structure of a sealing device 1 according to one embodiment of the present invention. Figure 1 : is a cross-sectional view of the sealing device 1 along the axis x. As described later, the sealing device 1 involved in the utility model is assembled to a hydrogen circulation pump, etc., which is used to supply unreacted hydrogen discharged from a fuel cell stack assembled in a fuel cell vehicle to the fuel cell stack again. Specifically, the sealing device 1 is used in the hydrogen circulation pump, etc. to seal between a rotating shaft and a housing, and the housing has a through hole for inserting the rotating shaft.

[0020] In the drawings, for the sake of convenience, one side in the direction along the axis x (hereinafter referred to as the "axial direction") is defined as the first side FS, and the other side opposite to the one side in the axial direction is defined as the second side SS. As described later, the first side FS is, for example, a gas side where a gas such as hydrogen exists, and the second side SS is, for example, a liquid side where a liquid such as a lubricant exists. In addition, in the direction orthogonal to the axis x (hereinafter referred to as the "radial direction"), the direction away from the axis x is defined as the outer peripheral side OC, and the direction close to the axis x is defined as the inner peripheral side IC. In addition, the direction around the axis x is defined as the circumferential direction.

[0021] Figure 2 1 is an enlarged cross-sectional view of the sealing device 1 in one direction, schematically showing the structure of the sealing device 1. Figure 1 and Figure 2 The sealing device 1 includes a retaining member 2, an annular member 3 retained by the retaining member 2, and an elastic body portion 4 at least partially covering the retaining member 2. The retaining member 2, the annular member 3, and the elastic body portion 4 are all formed into a circular ring centered on the axis x. The retaining member 2 includes an outer retaining member 10 disposed on the outer circumferential side OC and an inner retaining member 20 disposed on the inner circumferential side IC. By fitting the inner retaining member 20 to the outer retaining member 10, the annular member 3 is axially retained between the outer retaining member 10 and the inner retaining member 20.

[0022] The outer retaining member 10 has an annular cylindrical portion 11 extending in the axial direction and an annular flange portion 12 extending from the cylindrical portion 11 to the inner circumference side IC on the second side SS. The cylindrical portion 11 is formed as a whole in a cylindrical shape with the axis x as the center axis. In this example, the flange portion 12 is formed by bending the end of the second side SS of the cylindrical portion 11 in the radial direction. An annular protrusion 13 protruding toward the inner circumference side IC is formed on the cylindrical portion 11. The protrusion 13 extends in an annular shape from the end of the first side FS on the opposite side of the end of the second side SS bent by the flange portion 12 to the inner circumference side IC. The protrusion 13 extends, for example, along an imaginary plane orthogonal to the axis x.

[0023] The cylindrical portion 11 has an outer peripheral surface 11a and an inner peripheral surface 11b facing each other in the radial direction. The outer peripheral surface 11a is a surface facing the outer peripheral side OC, and the inner peripheral surface 11b is a surface facing the inner peripheral side IC. Steps are also formed on the outer peripheral surface 11a and the inner peripheral surface 11b by the step 11c formed on the cylindrical portion 11. The flange portion 12 has a side surface 12a and a side surface 12b facing each other in the axial direction. The side surface 12a is a surface facing the first side FS, and the side surface 12b is a surface facing the second side SS. The side surface 12b is connected to the outer peripheral surface 11a, and on the other hand, the side surface 12a is connected to the inner peripheral surface 11b. Steps are also formed on the side surfaces 12a and 12b by the step 12c formed on the flange portion 12.

[0024] The inner holding member 20 has an annular cylindrical portion 21 extending in the axial direction and an annular flange portion 22 extending from the cylindrical portion 21 to the inner circumference IC on the second side SS. The cylindrical portion 21 is formed as a whole in a cylindrical shape with the axis x as the center axis. In this example, the flange portion 22 is formed by bending in the radial direction from the end of the second side SS of the cylindrical portion 21. The cylindrical portion 21 is arranged at a position closer to the inner circumference IC than the cylindrical portion 11 of the outer holding member 10. The flange portion 22 is arranged at a position closer to the first side FS than the flange portion 12 of the outer holding member 10.

[0025] The cylindrical portion 21 has an outer peripheral surface 21a and an inner peripheral surface 21b facing each other in the radial direction. The outer peripheral surface 21a is a surface facing the outer peripheral side OC, and the inner peripheral surface 21b is a surface facing the inner peripheral side IC. In this example, the outer peripheral surface 21a is opposite to the inner peripheral surface 11b of the cylindrical portion 11 of the outer retaining member 10. The cylindrical portion 21 abuts against the protrusion 13 at the end surface 21c facing the first side FS. The flange portion 22 has a side surface 22a and a side surface 22b facing each other in the axial direction. The side surface 22a is a surface facing the first side FS, and the side surface 22b is a surface facing the second side SS. The side surface 22b is connected to the outer peripheral surface 21a, and on the other hand, the side surface 22a is connected to the inner peripheral surface 21b. The side surface 22b is opposite to the side surface 12a of the flange portion 12 of the outer retaining member 10.

[0026] The annular component 3 has a base 31 that is annular around the axis x and a contact portion 32 that is continuous with the end of the inner circumferential side IC of the base 31. The base 31 is a plate-like portion that extends along an imaginary plane that is orthogonal to the axis x. The base 31 has a side surface 31a and a side surface 31b that are opposite to each other in the axial direction. In this example, the side surface 31a and the side surface 31b extend along an imaginary plane that is orthogonal to the axis x. The side surface 31a is a surface facing the first side FS, and the side surface 31b is a surface facing the second side SS. The outer peripheral end 31c of the base 31 extends along a circle centered on the axis x. In this example, the outer peripheral end 31c abuts against the inner peripheral surface 11b of the cylindrical portion 11 of the outer retaining component 10.

[0027] The base 31 is sandwiched between the flange 12 of the outer holding member 10 and the flange 22 of the inner holding member 20 in the axial direction. At this time, the end face 21c of the cylindrical portion 21 abuts against the protrusion 13 of the cylindrical portion 11. In a state where the base 31 is sandwiched between the side 12a of the flange 12 and the side 22b of the flange 22, the axial distance between the side 12a of the flange 12 and the side 22b of the flange 22 is set to be smaller than the axial thickness of the base 31. As a result, the base 31 is sandwiched between the flange 12 and the flange 22 in a state where it is compressed in the axial direction. Therefore, the annular member 3 can be firmly held between the flange 12 of the outer holding member 10 and the flange 22 of the inner holding member 20.

[0028] The contact portion 32 is a plate-like portion having a side surface 32a and a side surface 32b facing away from each other. The contact portion 32 extends obliquely toward the first side FS from the outer peripheral end connected to the base 31 toward the inner peripheral end 32c. In this example, the contact portion 32 has a shape that decreases in diameter in the axial direction toward the first side FS. The side surface 32b is a surface facing the inner peripheral side IC, and the side surface 32a is a surface facing the outer peripheral side OC. The side surface 32b is connected to the side surface 31a, and on the other hand, the side surface 32a is connected to the side surface 31b. The contact portion 32 is configured so that when the sealing device 1 is installed in the use state of the application object, the inner peripheral end 32c of the inner peripheral side IC of the contact portion 32 can slidably contact the outer peripheral surface of the rotating shaft of the application object.

[0029] The elastomer portion 4 is formed of an annular elastomer centered on the axis x. The elastomer portion 4 is integrally mounted on the outer retaining component 10. Specifically, the elastomer portion 4 is integrally formed with the outer retaining component 10 in a manner that covers the outer retaining component 10 from the outer peripheral side OC and the second side SS. The elastomer portion 4 has a radial cover 41 and an axial cover 42. In this example, the radial cover 41 covers the cylindrical portion 11 of the outer retaining component 10 from the outer peripheral side OC. The axial cover 42 covers the flange portion 12 of the outer retaining component 10 from the second side SS. The radial thickness of the radial cover 41 is set to generate a fitting force of a specified size when the sealing device 1 is pressed into the inner peripheral surface of the through hole of the housing of the application object and is compressed in the radial direction. The fitting force is a force toward the outer peripheral side OC. In addition, in this example, the axial cover 42 also covers the end of the inner peripheral side IC of the flange portion 12 and a part of the inner peripheral side IC of the side 12a.

[0030] The outer retaining member 10 and the inner retaining member 20 are manufactured, for example, by stamping and forging of metal materials. The metal material includes, for example, stainless steel. The annular member 3 is formed, for example, of a fluororesin material. The fluororesin material includes, for example, PTFE (polytetrafluoroethylene). The elastomer portion 4 is formed, for example, of an elastic resin material. The elastic resin material includes, for example, synthetic rubbers such as nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM). The elastomer portion 4 is formed, for example, by crosslinking (vulcanization) molding using a molding die equipped with the outer retaining member 10.

[0031] When the sealing device 1 is assembled, as described above, the elastomer portion 4 is formed using a molding die provided with the outer retaining member 10, whereby the elastomer portion 4 is bonded to the outer retaining member 10 by cross-linking bonding. The annular member 3 is arranged on the flange portion 12 of the outer retaining member 10 from the first side FS. Thereafter, the inner retaining member 20 is embedded in the outer retaining member 10 from the first side FS. The thickness of the base portion 31 of the annular member 3 is greater than the distance between the flange portion 12 and the flange portion 22 in the axial direction. As a result, the flange portion 22 of the inner retaining member 20 compresses the base portion 31 of the annular member 3 in the axial direction and embeds it in the outer retaining member 10. The end face 21c of the first side FS of the cylindrical portion 21 abuts against the protrusion 13 of the outer retaining member 10. The sealing device 1 is assembled in this way.

[0032] Next, the operation of the sealing device 1 will be described below. Figure 3 1 is a cross-sectional view schematically showing the structure of a hydrogen circulation pump 50 to which the sealing device 1 is applied. The hydrogen circulation pump 50 is installed in, for example, a hydrogen fuel cell. The hydrogen fuel cell includes, for example: a fuel cell stack that generates electricity by reacting oxygen with hydrogen; an air compressor that supplies oxygen to the fuel cell stack; a high-pressure hydrogen tank that supplies hydrogen to the fuel cell stack; a gas-liquid separation device that separates water discharged from the fuel cell stack from unreacted hydrogen; and a hydrogen circulation pump 50 that supplies unreacted hydrogen to the fuel cell stack. The hydrogen circulation pump 50 is a pump for returning unreacted hydrogen separated from water by the gas-liquid separation device to the fuel cell stack.

[0033] The hydrogen circulation pump 50 has a motor housing 51 and a pump housing 52 mounted on the motor housing 51. A motor 53 is arranged in the motor housing 51. The motor 53 has a rotor 55 fixed on a rotating shaft 54 ​​and a stator 56 fixed on the motor housing 51. The rotating shaft 54 ​​extends from the motor housing 51 into the pump housing 52. One end of the rotating shaft 54 ​​is rotatably supported on the motor housing 51 by a bearing 57, and the other end of the rotating shaft 54 ​​is rotatably supported on the pump housing 52 by a bearing 58. In addition, between one end and the other end, the rotating shaft 54 ​​is supported by a pair of bearings 59, for example. The rotating shaft 54 ​​can rotate around its axis by magnetic interaction between the permanent magnets of the rotor 55 and the coils of the stator 56.

[0034] A pump chamber 52a and a gear chamber 52b are defined in the pump housing 52. A rotating shaft 60 extending parallel to the rotating shaft 54 ​​is arranged in the pump housing 52. The rotating shaft 60 extends from the gear chamber 52b into the pump chamber 52a. The rotating shaft 60 is rotatably supported on the pump housing 52 by a pair of bearings 61 in the gear chamber 52b. Specifically, the rotating shaft 60 is cantilevered by a pair of bearings 61. In the gear chamber 52b, gears 63 and 64 are respectively installed on the rotating shaft 54 ​​and the rotating shaft 60. The gear 63 and the gear 64 are meshed with each other. As a result, the rotation of the rotating shaft 54 ​​around the axis is transmitted to the rotating shaft 60. In this way, the rotating shaft 60 can rotate around its axis.

[0035] The pump chamber 52a is connected to the fuel cell stack. In the pump chamber 52a, a driving rotor 65 and a driven rotor 66 are installed on the rotating shaft 54 ​​and the rotating shaft 60, respectively. The driving rotor 65 rotates by the rotation of the rotating shaft 54, and rotates by the rotating shaft 60 based on the rotation of the rotating shaft 54, thereby rotating the driven rotor 66. As a result, the unreacted hydrogen sucked into the pump chamber 52a from the fuel cell stack is discharged from the pump chamber 52a to the fuel cell stack. In this example, the above-mentioned sealing device 1 is applied to the through holes 67, 68 of the pump housing 52 in which the rotating shafts 54, 60 are arranged between the pump chamber 52a and the gear chamber 52b, and the through hole 69 of the pump housing 52 that connects the gear chamber 52b and the space in the motor housing 51.

[0036] Figure 4 2 is a cross-sectional view showing the sealing device 1 in use. Figure 4 , a situation in which the sealing device 1 is used to seal the through hole 67 between the pump chamber 52a and the gear chamber 52b is shown. Specifically, the sealing device 1 is installed on the inner circumferential surface 67a of the through hole 67 by being pressed in. As a result, the radial cover 41 of the elastomer portion 4 is compressed radially between the cylindrical portion 11 of the outer retaining member 10, generating a fitting force, which is a force toward the outer peripheral side OC. In this example, the sealing device 1 also abuts against the end face 67b of the first side FS of the through hole 67 at the protrusion 13 of the outer retaining member 10. On the other hand, the inner circumferential end 32c of the contact portion 32 contacts the outer circumferential surface 54a of the rotating shaft 54. When the rotating shaft 54 ​​rotates around the axis x, the inner circumferential end 32c slides on the outer circumferential surface 54a of the rotating shaft 54. In this way, the hydrogen in the pump chamber 52a and the fluid such as the lubricant in the gear chamber 52b are sealed.

[0037] In the sealing device 1 as described above, the annular member 3 is sandwiched between the outer retaining member 10 and the inner retaining member 20 in the axial direction. The outer peripheral side OC of the outer retaining member 10 is covered by the radial cover 41 of the elastic body portion 4. According to such a structure, when the sealing device 1 is installed on the inner peripheral surface 67a of the through hole 67 by pressing, the fitting force is generated by the compression of the radial cover 41 of the elastic body portion 40. In this way, the sealing device 1 can be easily installed in the through hole 67. The sealing device 1 is a simple structure in which the annular member 3 is sandwiched between the outer retaining member 10 and the inner retaining member 20, so the space occupied by the sealing device 1 can be reduced compared with the past. In addition, since the number of components is small, the assembly cost of the sealing device 1 can be reduced.

[0038] The present invention has been described above by the above-mentioned embodiments, but the technical scope of the present invention is not limited to the scope described in the above-mentioned embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above-mentioned embodiments. According to the description of the claims, the method to which such changes or improvements are made is also included in the technical scope of the present invention.

[0039] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the interpretation of the present invention. In addition, the above-described embodiments do not limit the objects of use utilized by the present invention, and the present invention can include all objects as its objects of use. The various components and their configurations, materials, conditions, shapes, and dimensions, etc., possessed by the above-described embodiments are not limited to the illustrated contents and can be appropriately changed. For example, the present invention includes differences generated in the implementation of manufacturing tolerances, etc. In addition, within the scope of technical non-contradiction, the components shown in different embodiments can be partially replaced or combined with each other. In addition, the various structures can be appropriately and selectively combined to achieve at least a portion of the above-mentioned topics and effects.

[0040] Description of Reference Numerals

[0041] 1 sealing device, 2 holding member, 3 annular member, 4 elastic body, 10 outer holding member, 20 inner holding member, 11 cylindrical portion, 11a outer peripheral surface, 11b inner peripheral surface, 11c step, 12 flange portion, 12a side surface, 12b side surface, 13 protrusion, 21 cylindrical portion, 21a outer peripheral surface, 21b inner peripheral surface, 21c end surface, 22 flange portion, 31 base, 31a side surface, 31b side surface, 31c outer peripheral end, 32 contact portion, 32a side surface, 32b side surface, 32 c inner circumferential end, 41 radial cover, 42 axial cover, 50 hydrogen circulation pump, 51 motor housing, 52 pump housing, 52a pump chamber, 52b gear chamber, 53 motor, 54 rotating shaft, 54a outer circumferential surface, 55 rotor, 56 stator, 57, 58, 59 bearing, 60 rotating shaft, 61 bearing, 63, 64 gears, 65, 66 rotor, 67, 68, 69 through hole, 67a inner circumferential surface, 67b end surface, FS first side, SS second side, OC outer circumferential side, IC inner circumferential side, x axis line.

Claims

1. A sealing device, characterized in that: include: A retaining member is annular with the axis as the center; an annular member made of a fluororesin material, the annular member being held by the holding member and extending toward the inner circumference; as well as The elastic body portion covers at least the outer peripheral side of the holding member.

2. The sealing device according to claim 1, characterized in that: The fluororesin material is PTFE.

3. The sealing device according to claim 1, characterized in that: The holding component comprises: an outer retaining member having a ring shape with the axis as the center; and The inner holding member is annular with the axis as the center and is embedded in the inner circumference of the outer holding member. The annular member is sandwiched between the outer holding member and the inner holding member in the axial direction.

4. The sealing device according to claim 3, characterized in that: The elastic body portion has: a radial cover covering an outer peripheral surface of the outer retaining member; and An axial cover covers the side surfaces of the outer retaining member.

5. The sealing device according to claim 1, characterized in that: The retaining member is formed of stainless steel.

6. A hydrogen circulation pump for a hydrogen fuel cell, characterized in that: include: Axis of rotation, rotation around an axis; A housing having a through hole for inserting the rotating shaft; as well as A sealing device is used to seal between the rotating shaft and the through hole. The sealing device comprises: A retaining member, which is annular with the axis as the center; an annular member made of a fluororesin material, the annular member being held by the holding member and extending toward the inner circumference to contact the rotating shaft; and The elastic body portion covers at least the outer peripheral side of the holding member and is sandwiched between the holding member and the housing.

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