Sealing structure

Abstract

The utility model provides a sealing structure capable of inhibiting invasion of muddy water and the like. A sealing structure is provided with a sealing device for sealing a gap between the outer peripheral surface of a rotating shaft rotatable about an axis and the inner peripheral surface of a hole into which the rotating shaft is inserted. The sealing device is provided with an annular reinforcing ring with the axis as the center and an elastic body part. The elastic body part is provided with an annular sealing lip which covers the reinforcing ring and makes contact with the outer circumferential surface of the rotating shaft, and a first annular dustproof lip and a second annular dustproof lip which are arranged from the sealing lip in one direction of the axis and make contact with the outer circumferential surface of the rotating shaft. And an annular side lip adjacent to the second dust lip in a radial direction orthogonal to the axis. The member is opposed to the sealing device in one direction along the axis and forms a labyrinth structure between the member and the side lip.

Description

Technical Field

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

[0002] For example, a sealing device such as an oil seal is installed on a crankshaft of a vehicle such as an automobile. In the sealing device, for example, a sealing lip and a dust lip slide on the outer peripheral surface of the crankshaft. Utility Model Content

[0003] Issues to be Solved by Utility Models

[0004] When the driving environment of an automobile is a harsh environment with a lot of mud and water, the amount of mud and water entering between the dust lip, the sealing lip and the crankshaft increases, thereby accelerating the wear of the dust lip and the sealing lip. Therefore, countermeasures against the intrusion of mud and water are important.

[0005] The present invention has been made in view of the above-mentioned problems, and its object is to provide a sealing structure capable of suppressing the intrusion of muddy water and the like.

[0006] Means for solving problems

[0007] In order to achieve the above-mentioned purpose, the sealing structure involved in the utility model is equipped with a sealing device, which is used to seal the gap between the outer peripheral surface of a rotating shaft that can rotate around an axis and the inner peripheral surface of a hole for inserting the rotating shaft, and the sealing structure includes: the sealing device has a reinforcing ring and an elastic body part that are annular with the axis as the center, the elastic body part has an annular sealing lip covering the reinforcing ring and contacting the outer peripheral surface of the rotating shaft, two annular first dustproof lips and second dustproof lips arranged from the sealing lip along one direction of the axis and contacting the outer peripheral surface of the rotating shaft, and an annular side lip adjacent to the second dustproof lip in a radial direction orthogonal to the axis; and

[0008] A component is opposed to the sealing device in the one direction along the axis and forms a labyrinth structure with the side lip.

[0009] In the sealing structure according to the present invention, the component is a pulley mounted on the rotating shaft and extending in the radial direction.

[0010] In the sealing structure of the present invention, the component is an oil slinger installed on the rotating shaft and extending in the radial direction.

[0011] In the sealing structure according to the present invention, the slinger includes: a flange portion extending in the radial direction; and an annular extending portion extending from the flange portion along the other direction of the axis.

[0012] In the sealing structure according to the present invention, the side lip is opposed to the extending portion in the radial direction.

[0013] In the sealing structure according to the present invention, the side lip is inclined toward the outer peripheral side in the radial direction.

[0014] In the sealing structure according to the present invention, the extending portion is inclined toward the outer peripheral side in the radial direction.

[0015] Utility Model Effect

[0016] According to the present invention, a sealing structure capable of suppressing the intrusion of muddy water or the like can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view schematically showing the structure of a sealing device 1 according to a specific example.

[0018] Figure 2 It is an enlarged cross-sectional view of a portion of one side of the sealing device 1 along the axis x.

[0019] Figure 3 It is a cross-sectional view schematically showing the structure of a sealing structure 10 according to one embodiment of the present invention.

[0020] Figure 4 It is a cross-sectional view schematically showing the structure of a sealing structure 10A according to another embodiment of the present invention.

[0021] Reference numerals:

[0022] 1 sealing device, 10, 10A sealing structure, 11 housing, 12 hole, 12a inner peripheral surface, 13 rotating shaft, 13a outer peripheral surface, 14 pulley (component), 14a side surface, 15 bolt, 16 oil slinger (component), 16a inner cylinder portion, 16b flange portion, 16c extension portion, 16d side surface, 16e inner peripheral surface, 2 reinforcement ring, 21 cylinder portion, 21a outer peripheral surface, 21b inner peripheral surface, 22 flange portion, 22a side surface, 22b side surface, 3 elastic body portion, 31 radial cover, 32 axial cover, 33 sealing portion, 34 side lip, 35 lip waist portion, 36 sealing lip, 36a lip front end portion, 36b lip front end, 36c sealing side surface, 36d gas side surface, 37 first dust lip, 38 second dust lip, 4 spring, FS first side, G gap, IC inner peripheral side, OC outer peripheral side, SS second side, x axis line. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 It is a cross-sectional view schematically showing the structure of a sealing device 1 according to a specific example. Figure 11 is a cross-sectional view of the sealing device 1 along the axis x. As described later, the sealing device 1 is mounted on, for example, a crankshaft assembled in a vehicle such as an automobile. Specifically, as described later, the sealing device 1 is used to seal a gap between a rotating shaft as a crankshaft and a housing having a hole for inserting the rotating shaft.

[0024] In the drawings, for convenience of explanation, 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 the atmosphere 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.

[0025] The sealing device 1 includes a reinforcement ring 2, an elastic body portion 3 formed integrally with the reinforcement ring 2, and a spring 4 mounted on the elastic body portion 3. The reinforcement ring 2, the elastic body portion 3, and the spring 4 are all formed into a circular ring shape centered on the axis x. The reinforcement ring 2 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 first side FS. The cylindrical portion 21 is formed into a cylindrical shape with the axis x as the center axis. In this example, the flange portion 22 is formed by bending the end of the first side FS of the cylindrical portion 21 in the radial direction.

[0026] 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. 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 22a is connected to the outer peripheral surface 21a, and the side surface 22b is connected to the inner peripheral surface 21b.

[0027] The elastomer portion 3 includes: a radial cover 31 covering the cylindrical portion 21 of the reinforcement ring 2; an axial cover 32 covering the flange portion 22 of the reinforcement ring 2; and a sealing portion 33 extending from the axial cover 32 to the second side SS. The radial cover 31, the axial cover 32, and the sealing portion 33 are formed integrally with each other. The radial cover 31 covers the outer peripheral surface 21a and the inner peripheral surface 21b of the cylindrical portion 21. That is, the cylindrical portion 21 is buried in the radial cover 31. The axial cover 32 extends radially from the end of the first side FS of the radial cover 31 to the inner peripheral side IC. The axial cover 32 extends as a whole along the side surface 22a of the flange portion 22. The axial cover 32 exposes a portion of the side surface 22b of the flange portion 22.

[0028] Figure 21 is an enlarged cross-sectional view of one side portion of the sealing device 1 along the axis x. Figure 1 and Figure 2 The axial cover 32 is provided with a side lip 34 extending in the axial direction toward the first side FS. The side lip 34 is formed in an annular shape with the axis x as the center. In this example, the side lip 34 extends from the axial cover 32 in the axial direction toward the first side FS, and extends obliquely toward the outer peripheral side OC relative to the axis x. That is, the side lip 34 extends toward the first side FS and the outer peripheral side OC.

[0029] The sealing portion 33 includes a lip waist portion 35, an annular sealing lip 36 extending from the lip waist portion 35 to the second side SS in the axial direction, two annular first dust lips 37 extending from the lip waist portion 35 to the inner circumference side IC, and an annular second dust lip 38. The lip waist portion 35 is a portion located near the end portion on the inner circumference side IC of the flange portion 22 of the reinforcement ring 2. The lip waist portion 35 is continuous with the end portion on the inner circumference side IC of the axial cover 32.

[0030] like Figure 2 As shown in FIG. 1 , the sealing lip 36 has a wedge-shaped lip front end portion 36a protruding toward the inner peripheral side IC. The lip front end portion 36a is located at the innermost peripheral side IC in a lip front end 36b that describes a circle centered on the axis x in a plane perpendicular to the axis x. The sealing lip 36 is formed so that, in the use state, the vicinity of the lip front end 36b is in close contact with the outer peripheral surface of the rotating shaft in a slidable manner.

[0031] The lip tip 36a defines an annular sealing side surface 36c facing the second side SS and an annular gas side surface 36d facing the first side FS. The sealing side surface 36c is a conical surface in the shape of a truncated cone whose diameter increases as it goes toward the second side SS. In addition, the gas side surface 36d is a conical surface in the shape of a truncated cone whose diameter increases as it goes toward the first side FS. A lip tip 36b is formed at the portion where the sealing side surface 36c and the gas side surface 36d intersect.

[0032] The first dust lip 37 is arranged from the sealing lip 36 to the first side FS in the axial direction. The first dust lip 37 extends from the lip waist portion 35 to the first side FS and the inner peripheral side IC. The second dust lip 38 is arranged from the first dust lip 37 to the first side FS in the axial direction. The second dust lip 38 extends from the lip waist portion 35 to the first side FS and the inner peripheral side IC. In this example, the first dust lip 37 and the second dust lip 38 extend from the lip waist portion 35 in substantially the same direction.

[0033] The length of the first dust lip 37 is set to be smaller than that of the second dust lip 38. With such a structure, the lip tip 36b and the end of the inner circumference side IC of the first dust lip 37 and the end of the inner circumference side IC of the second dust lip 38 are arranged at substantially the same position in the radial direction. The first dust lip 37 and the second dust lip 38 prevent foreign matter such as muddy water, sand, and dust from entering the direction of the lip tip 36a in the use state. In this example, in the axial direction, the side lip 34 extends further to the first side FS than the second dust lip 38.

[0034] The spring 4 is disposed, for example, at a position radially opposed to the lip tip 36b across the seal lip 36. The spring 4 applies force to the lip tip 36a, i.e., the lip tip 36b, toward the inner circumference IC. Thus, the spring 4 applies a tightening force of a predetermined magnitude, for example, to the lip tip 36a, i.e., the lip tip 36b, relative to the outer circumference of the rotating shaft.

[0035] The reinforcement ring 2 is manufactured, for example, by stamping or forging of a metal material. The metal material includes, for example, stainless steel. The elastomer portion 3 is formed, for example, by 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 3 is formed, for example, by crosslinking (vulcanization) molding using a molding die equipped with the reinforcement ring 2. In this way, the elastomer portion 3 is formed integrally with the reinforcement ring 2. The spring 4 is formed, for example, by a metal material such as stainless steel.

[0036] Next, the structure of the sealing structure 10 according to one embodiment of the present invention will be described. Figure 3 It is a cross-sectional view schematically showing the structure of a sealing structure 10 involved in one embodiment of the utility model, and is a partial cross-sectional view of a section along the axis x. The sealing structure 10 comprises: a housing 11; a rotating shaft 13, which is inserted into a hole 12 of the housing 11; and the above-mentioned sealing device 1, which seals the gap G formed between the inner peripheral surface 12a of the hole 12 and the outer peripheral surface 13a of the rotating shaft 13. The rotating shaft 13 is, for example, a crankshaft of an engine of a vehicle such as an automobile. In this example, a component, namely a pulley 14, is installed on the end face of the first side FS of the rotating shaft 13. During installation, a fixing component such as a bolt 15 is used. In this example, the pulley 14 is formed into a disc shape extending in a circular shape in the radial direction.

[0037] The hole 12 of the housing 11 is, for example, a cylindrical space extending along the axis x. That is, the inner circumferential surface 12a of the hole 12 is a cylindrical surface with the axis x as the center axis. On the other hand, the rotating shaft 13 is, for example, a cylindrical rotating shaft extending along the axis x. The outer circumferential surface 13a of the rotating shaft 13 is a cylindrical surface with the axis x as the center axis. The hole 12 and the rotating shaft 13 are defined as being coaxial. Between the inner circumferential surface 12a of the hole 12 and the outer circumferential surface 13a of the rotating shaft 13, a gap G extends in an annular shape. The gap G is radially opposed to the side surface 14a of the second side SS of the pulley 14. In this example, the pulley 14 has a diameter in the radial direction that is substantially the same as the diameter of the inner circumferential surface 12a of the hole 12.

[0038] The sealing device 1 is fitted into the gap G. Specifically, the radial cover 31 of the elastomer portion 3 is fitted into the hole 12 of the housing 11. The radial cover 31 is compressed in the radial direction between the inner peripheral surface 12a of the hole 12 and the outer peripheral surface 21a of the cylindrical portion 21 of the reinforcement ring 2. In this way, the radial cover 31 generates a force toward the inner peripheral side IC when compressed in the radial direction, that is, a fitting force, of a predetermined magnitude. On the other hand, the sealing lip 36 contacts the outer peripheral surface 13a of the rotating shaft 13 at the lip front end 36b. Similarly, the ends of the inner peripheral side IC of the first dust lip 37 and the second dust lip 38 also contact the outer peripheral surface 13a of the rotating shaft 13.

[0039] In the sealing structure 10, the side surface 14a of the pulley 14 is opposite to the sealing device 1. The annular side lip 34 of the sealing device 1 is inclined toward the first side FS and the outer peripheral side OC. In this way, a labyrinth structure is formed by the side lip 34 and the pulley 14. When the rotating shaft 13 rotates around the axis x, the sealing lip 36, the first dust lip 37, and the second dust lip 38 slide on the outer peripheral surface 13a of the rotating shaft 13, so that the sealing device 1 seals between the oil and the atmosphere. The labyrinth structure formed by the side lip 34 and the pulley 14 can suppress the muddy water from flowing along the rotating shaft 13. Figure 3 Radial intrusion of arrow A.

[0040] In addition, in the sealing structure 10, the two first dust lips 37 and the second dust lips 38 slide on the outer peripheral surface 13a of the rotating shaft 13. Even if muddy water or the like passes over the side lip 34 and intrudes into the inner peripheral side IC, the first dust lip 37 and the second dust lip 38 can suppress the intrusion of muddy water or the like into the oil side. As a result, foreign matter is suppressed from intruding between the first dust lip 37, the second dust lip 38, the sealing lip 36 and the outer peripheral surface 13a of the rotating shaft 13, thereby suppressing the wear of each of the first dust lip 37, the second dust lip 38, and the sealing lip 36. The sealing performance of the sealing device 1 can be improved. In this way, the product life of the sealing device 1 can be extended.

[0041] Figure 41 is a cross-sectional view schematically showing the structure of a sealing structure 10A according to another embodiment of the present invention. In the sealing structure 10A, a slinger 16 is further added to the above-mentioned sealing structure 10. In this example, the slinger 16 is mounted on the rotating shaft 13 between the pulley 14 and the sealing device 1 in the axial direction. The slinger 16 functions as a protective cover against muddy water and the like. The structures other than the slinger 16 are the same as those of the above-mentioned sealing structure 10, and therefore the same reference numerals are given to these structures, and repeated descriptions are omitted here.

[0042] In one example, the slinger 16 includes an annular inner cylinder portion 16a centered on the axis x, an annular flange portion 16b extending radially from the inner cylinder portion 16a, and an annular extension portion 16c extending from the end portion of the outer circumference side OC of the flange portion 16b toward the outer circumference side OC and the second side SS. The slinger 16 is formed integrally of, for example, a metal material or a resin material. The inner cylinder portion 16a is mounted on the outer circumference surface 13a of the rotating shaft 13 by, for example, press-fitting. However, the inner cylinder portion 16a may be mounted on the outer circumference surface 13a of the rotating shaft 13 by a method other than press-fitting.

[0043] In this example, the flange portion 16b is an annular portion bent from the end portion of the second side SS of the inner tube portion 16a and extending in the radial direction. The side surface 16d of the second side SS of the flange portion 16b is axially opposed to the sealing device 1. In this example, the side surface 16d is axially opposed to the side lip 34. In this example, the end portion of the first side FS of the side lip 34 is opposed to the vicinity of the end portion of the outer peripheral side OC of the flange portion 16b. A gap is formed between the side surface 16d of the flange portion 16b and the end portion of the first side FS of the side lip 34.

[0044] In this example, the extension portion 16c is an annular portion that is bent from the end of the outer peripheral side OC of the flange portion 16b and extends toward the outer peripheral side OC and the second side SS. The end of the second side SS of the extension portion 16c is opposite to the axial cover 32 of the elastomer portion 3. That is, a predetermined gap is formed between the end of the second side SS of the extension portion 16c and the axial cover 32. At the same time, the extension portion 16c is opposite to the side lip 34 in the radial direction at its inner peripheral surface 16e. The inner peripheral surface 16e is arranged from the side lip 34 to the outer peripheral side OC. The extension portion 16c is inclined toward the outer peripheral side OC. The inner peripheral surface 16e of the extension portion 16c is a truncated cone-shaped surface that expands toward the outer peripheral side OC as it moves toward the second side SS.

[0045] In such a sealing structure 10A, the side surface 16d of the oil slinger 16 is opposed to the side lip 34 of the sealing device 1 in the axial direction. The inner peripheral surface 16e of the oil slinger 16 is opposed to the side lip 34 in the radial direction. In this way, a labyrinth structure is formed by the side lip 34 and the oil slinger 16. When the rotating shaft 13 rotates around the axis x, the labyrinth structure formed by the side lip 34 and the oil slinger 16 can suppress the muddy water from moving in the same direction along the rotating shaft 13. Figure 4 Radial as well as axial intrusion of arrow A.

[0046] The oil slinger 16 rotates around the axis x together with the rotating shaft 13. The inner circumferential surface 16e of the extension portion 16c expands toward the outer circumferential side OC as it moves toward the second side SS. According to such a structure, for example, muddy water and the like adhering to the inner circumferential surface 16e of the extension portion 16c can be blown away toward the outer circumferential side OC by centrifugal force. As a result, the intrusion of muddy water and the like in the radial and axial directions can be further suppressed. In addition, as described above, even if muddy water and the like pass over the side lip 34 and intrude into the inner circumferential side IC, the intrusion of muddy water and the like toward the oil side can be suppressed by the first dust lip 37 and the second dust lip 38. The sealing performance of the sealing device 1 can be improved.

[0047] The present invention has been described above by the above embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. According to the description of the claims, such changes or improvements can also be included in the technical scope of the present invention.

[0048] The above-described embodiments are used to facilitate the understanding of the present invention, and are not used 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 may include all objects of use as its objects of use. The various components and their configurations, materials, conditions, shapes, and dimensions possessed by the above-described embodiments are not limited to the illustrated contents, and may be appropriately changed. For example, the present invention includes differences arising from the implementation of manufacturing tolerances, etc. In addition, within the scope of technical non-contradiction, the components shown in different embodiments may be partially replaced or combined with each other. In addition, in order to achieve at least a portion of the above-mentioned subjects and effects, the various structures may be appropriately and selectively combined.

Claims

1. A sealing structure comprising a sealing device for sealing a gap between an outer peripheral surface of a rotating shaft rotatable about an axis and an inner peripheral surface of a hole into which the rotating shaft is inserted, characterized in that: The sealing structure comprises: The sealing device comprises a reinforcing ring and an elastic body portion which are annular with the axis as the center, the elastic body portion comprising an annular sealing lip covering the reinforcing ring and contacting the outer peripheral surface of the rotating shaft, two annular first dust lip and second dust lip arranged along one direction of the axis from the sealing lip and contacting the outer peripheral surface of the rotating shaft, and an annular side lip adjacent to the second dust lip in a radial direction orthogonal to the axis; and A component is opposed to the sealing device in the one direction along the axis and forms a labyrinth structure with the side lip.

2. The sealing structure according to claim 1, characterized in that: The component is a pulley mounted on the rotating shaft and extending in the radial direction.

3. The sealing structure according to claim 1, characterized in that: The component is an oil slinger mounted on the rotating shaft and extending in the radial direction.

4. The sealing structure according to claim 3, characterized in that: The slinger includes a flange portion extending in the radial direction and an annular extending portion extending from the flange portion in the other direction of the axis.

5. The sealing structure according to claim 4, characterized in that: The side lip is opposed to the extension portion in the radial direction.

6. The sealing structure according to claim 5, characterized in that: The side lip is inclined toward the outer peripheral side in the radial direction.

7. The sealing structure according to claim 5, characterized in that: The extending portion is inclined toward the outer peripheral side in the radial direction.

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