阅读说明：本技术 密封装置 (Sealing device ) 是由 铃木敦志 于 2020-04-24 设计创作，主要内容包括：密封装置具有：安装在轴孔的内周面的安装部；配置在安装部的径向内侧的圆筒部；与旋转轴的外周面接触的密封唇部；将安装部与圆筒部连接的波纹部；配置在圆筒部的径向内侧并供旋转轴的外周面滑动的树脂制的环状的滑动构件。圆筒部、密封唇部和波纹部由弹性比树脂大的弹性材料形成。圆筒部具有朝向径向内侧突出的突出部,突出部为沿周向连续的环状突起或者具有沿周向隔开间隔配置的多个突起。突出部具有与旋转轴正交的2个表面。在滑动构件的外周面形成有周槽,周槽具有圆柱状的底周面和与底周面正交的2个侧壁面。突出部嵌入在周槽中,突出部的2个表面分别与周槽的2个侧壁面接触。(The sealing device has: a mounting portion mounted on the inner peripheral surface of the shaft hole; a cylindrical portion disposed radially inward of the mounting portion; a seal lip portion contacting an outer circumferential surface of the rotary shaft; a bellows portion connecting the mounting portion and the cylindrical portion; and an annular sliding member made of resin and disposed radially inside the cylindrical portion and configured to slide on an outer circumferential surface of the rotating shaft. The cylindrical portion, the seal lip portion, and the bellows portion are formed of an elastic material having elasticity greater than that of resin. The cylindrical portion has a protruding portion protruding radially inward, and the protruding portion is an annular protrusion continuous in the circumferential direction or has a plurality of protrusions arranged at intervals in the circumferential direction. The projection has 2 surfaces orthogonal to the axis of rotation. A circumferential groove is formed in the outer circumferential surface of the sliding member, and the circumferential groove has a cylindrical bottom circumferential surface and 2 side wall surfaces orthogonal to the bottom circumferential surface. The protrusion is fitted into the peripheral groove, and 2 surfaces of the protrusion are in contact with 2 side wall surfaces of the peripheral groove, respectively.)

1. A sealing device for closing a gap between a housing and a rotating shaft disposed in a shaft hole of the housing, the sealing device comprising:

an annular mounting portion mounted on an inner peripheral surface of the shaft hole;

a cylindrical portion disposed radially inward of the mounting portion;

a seal lip portion extending from the cylindrical portion and contacting an outer circumferential surface of the rotary shaft;

a bellows portion connecting the mounting portion and the cylindrical portion; and

a resin annular sliding member disposed radially inward of the cylindrical portion and adapted to slide on an outer peripheral surface of the rotating shaft,

the cylindrical portion, the seal lip portion, and the bellows portion are formed of an elastic material having elasticity greater than that of the resin,

the cylindrical portion has a protruding portion protruding radially inward, the protruding portion being an annular protrusion continuous in the circumferential direction or having a plurality of protrusions arranged at intervals in the circumferential direction, the protruding portion having 2 surfaces orthogonal to the rotation axis,

a circumferential groove having a cylindrical bottom circumferential surface and 2 side wall surfaces orthogonal to the bottom circumferential surface is formed on an outer circumferential surface of the sliding member,

the protrusion is embedded in the circumferential groove, and 2 surfaces of the protrusion are in contact with 2 side wall surfaces of the circumferential groove, respectively.

2. The sealing device of claim 1,

at an end of the sliding member, there are formed: an expanding portion expanding radially outward; and a hook portion extending in an axial direction from the expanding portion,

the expansion part is a flange continuous along the circumferential direction or is provided with a plurality of projections arranged at intervals along the circumferential direction,

the hook part is a cylinder which is continuous along the circumferential direction or is provided with a plurality of fragments which are arranged at intervals along the circumferential direction, the hook part and the circumferential groove are overlapped in the radial direction,

the protruding portion is formed at an end portion of the cylindrical portion,

an end surface circumferential groove that radially overlaps with the protruding portion is formed on an end surface of the cylindrical portion on a radially outer side of the protruding portion,

the hook portion of the slide member is embedded in the end face peripheral groove.

3. Sealing device according to claim 1 or 2,

at an end of the sliding member, there are formed: an expanding portion that expands radially outward and contacts an end surface of the cylindrical portion; and an outside hook portion extending in an axial direction from the expanded portion,

the expansion part is a flange continuous along the circumferential direction or is provided with a plurality of projections arranged at intervals along the circumferential direction,

the outer hook part is a cylinder which is continuous along the circumferential direction or is provided with a plurality of fragments which are arranged at intervals along the circumferential direction,

the outside hook portion is in contact with an outer peripheral surface of the cylindrical portion.

Technical Field

The present invention relates to a sealing device suitable for use as a steering dust seal.

Background

The steering dust seal is disposed in the front instrument panel, and a steering shaft is rotatably inserted into the steering dust seal (patent document 1).

The steering dust seal has a function of suppressing entry of foreign matter from the engine room into the passenger compartment (dust, muddy water, etc.), and suppressing transmission of sound from the engine room into the passenger compartment.

The steering gear dust seal described in patent document 1 includes a bellows portion made of an elastic material, a cylindrical portion made of an elastic material and disposed inside the bellows portion, and a low-friction sliding ring disposed inside the cylindrical portion.

The low-friction slip ring is disposed so as to be slidably in contact with the outer peripheral surface of the steering shaft around the steering shaft. The low-friction slip ring is formed of a resin having a small friction coefficient, and suppresses generation of abnormal noise when the steering shaft rotates.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-91077

Disclosure of Invention

Technical problem to be solved by the invention

A lip capable of sliding contact with a steering shaft is formed in a cylindrical portion disposed around a low-friction slip ring, and the lip suppresses entry of foreign matter from an engine room into a passenger compartment. In order to stably contact the lip with the outer peripheral surface of the steering shaft over the entire periphery, it is preferable that the low-friction slide ring having high rigidity be stably and reliably coupled to the cylindrical portion made of an elastic material. For example, it is desirable that the lip continuously contact the outer peripheral surface of the steering shaft over the entire circumference even if the steering shaft is eccentric with respect to the housing. In addition, in the case where the steering shaft is provided in the tilt steering mechanism, it is desirable that the lip continuously contact the outer peripheral surface of the steering shaft over the entire circumference even if the steering shaft is tilted.

Accordingly, the present invention provides a sealing device that can stably connect an annular sliding member and a cylindrical portion made of an elastic material.

Means for solving the technical problem

A sealing device according to an aspect of the present invention is a sealing device that seals a gap between a housing and a rotating shaft disposed in a shaft hole of the housing, the sealing device including: an annular mounting portion mounted on an inner peripheral surface of the shaft hole; a cylindrical portion disposed radially inward of the mounting portion; a seal lip portion extending from the cylindrical portion and contacting an outer circumferential surface of the rotary shaft; a bellows portion connecting the mounting portion and the cylindrical portion; and a resin annular sliding member disposed radially inward of the cylindrical portion and configured to slide on an outer peripheral surface of the rotating shaft. The cylindrical portion, the seal lip portion, and the bellows portion are formed of an elastic material having elasticity greater than that of the resin. The cylindrical portion has a protruding portion protruding radially inward, the protruding portion being an annular protrusion continuous in the circumferential direction or having a plurality of protrusions arranged at intervals in the circumferential direction, the protruding portion having 2 surfaces orthogonal to the rotation axis. A circumferential groove having a cylindrical bottom circumferential surface and 2 side wall surfaces orthogonal to the bottom circumferential surface is formed on an outer circumferential surface of the sliding member. The protrusion is embedded in the circumferential groove, and 2 surfaces of the protrusion are in contact with 2 side wall surfaces of the circumferential groove, respectively.

In this embodiment, the protrusion portion protruding radially inward in the cylindrical portion made of an elastic material is fitted in the circumferential groove of the outer circumferential surface of the sliding member, and 2 surfaces of the protrusion portion are in contact with 2 side wall surfaces of the circumferential groove, respectively, so that the sliding member and the cylindrical portion are reliably coupled, and the coupling is stable. Therefore, even if the rotating shaft (steering shaft) is eccentric or inclined with respect to the housing, the seal lip portion is continuously in contact with the outer peripheral surface of the rotating shaft over the entire circumference.

Drawings

Fig. 1 is a sectional view showing a sealing device according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view of a part of the sealing device of fig. 1 showing a rotation axis thereof being inclined in an enlarged manner.

Fig. 3 is a bottom view of a portion of the sealing device shown in fig. 2.

Fig. 4 is a cross-sectional view of a part of a sealing device of a comparative example showing an enlarged state in which a rotation shaft is inclined.

Fig. 5 is a bottom view of a part of a sealing device according to a modification of the first embodiment.

Fig. 6 is a cross-sectional view of a part of the sealing device of the second embodiment showing an enlarged state in which the rotation axis is inclined.

Fig. 7 is a bottom view of a portion of the sealing device shown in fig. 6.

Fig. 8 is a bottom view of a part of a sealing device according to a modification of the second embodiment.

Fig. 9 is a sectional view showing a sealing device of a third embodiment of the present invention.

Fig. 10 is a cross-sectional view of a part of the sealing device of fig. 9 showing a state where the rotation axis is inclined in an enlarged manner.

Detailed Description

Various embodiments of the present invention will be described below with reference to the drawings. The scale of the drawings is not necessarily exact, and some features may be exaggerated or omitted.

First embodiment

As shown in fig. 1, a sealing device 1 according to a first embodiment of the present invention is a steering dust seal for closing a gap between a housing (front instrument panel) 2 and a rotating shaft (steering shaft) 4 disposed in a shaft hole 2A of the housing 2. The rotary shaft 4 rotates about the axis Ax. The sealing device 1 is a ring-shaped member, and a left half of the sealing device 1 is shown in fig. 1. In fig. 1, reference symbol E shows a space on the engine compartment side, and P shows a space on the passenger compartment side.

The sealing device 1 includes 2 sealing portions 10, 40 having mutually similar structures.

The seal portion 10 is basically a highly elastic member formed of an elastic material, for example, an elastomer, and includes an annular mounting portion 12 mounted on the inner peripheral surface of the shaft hole 2A, a cylindrical portion 14 disposed radially inward of the mounting portion 12, and a meandering bellows portion 16 connecting the mounting portion 12 and the cylindrical portion 14.

Further, the seal portion 10 has a seal lip portion 18, and the seal lip portion 18 extends from the cylindrical portion 14 toward the radially inner side and toward the engine compartment-side space E, and is in contact with the outer circumferential surface of the rotary shaft 4 over the entire circumference. The seal lip 18 includes a plurality of seal lips 18A, 18B, and 18C slidably contacting the rotary shaft 4. The seal lips 18A, 18B, 18C are elastically deformed by contact with the rotary shaft 4. The cylindrical portion 14, the bellows portion 16 and the sealing lip portion 18 are formed of an elastic material, such as an elastomer.

In the present embodiment, although 3 seal lips 18A, 18B, and 18C are provided, it is only necessary that at least 1 seal lip is in contact with the rotating shaft 4, and it is not always necessary that 3 seal lips 18A, 18B, and 18C are in contact with the rotating shaft 4 at the same time. The number of the seal lips is not limited to the embodiment, and may be 1, 2, or 4 or more.

The mounting portion 12 has: an elastic ring 20 formed of an elastic material, such as an elastomer; and a rigid ring 22 fixedly bonded around the elastic ring 20 and formed of a rigid material such as metal. The resilient ring 20 may be formed from the same material as the cylindrical portion 14, the bellows 16 and the sealing lip 18, in which case the resilient ring 20 is connected to the bellows 16.

The rigid ring 22 is fitted (pressed) into the shaft hole 2A. In the rigid ring 22, one end portion 22a has a smaller diameter than the other portions, and a portion 20a of the elastic ring 20 is disposed around the end portion 22a over the entire circumference. A portion 20a is compressed between the end 22a of the rigid ring 22 and the housing 2, closing the gap between the mounting portion 12 and the housing 2.

The rotating shaft 4 is a steering shaft provided in the tilt steering mechanism. Therefore, the rotation shaft 4 is tilted by the driver. In addition, the rotary shaft 4 may be eccentric with respect to the shaft hole 2A. The bellows 16 is a portion that is easily elastically deformed, and is provided to allow movement, i.e., inclination and eccentricity, of the rotary shaft 4 by elastic deformation thereof, and the seal lips 18A, 18B, and 18C can contact the outer peripheral surface of the rotary shaft 4 over the entire circumference.

Further, the seal portion 10 includes a sliding member 24, and the sliding member 24 is disposed inside the cylindrical portion 14 and fixed to the annular shape of the cylindrical portion 14. The sliding member 24 can be fixed to the cylindrical portion 14 by fitting a convex portion formed on the outer peripheral surface of the sliding member 24 into a concave portion formed on the inner peripheral surface of the cylindrical portion 14. The manner of fixing the slide member 24 to the cylindrical portion 14 is not limited.

The sliding member 24 is provided so that the seal lips 18A, 18B, and 18C can contact the outer peripheral surface of the rotating shaft 4 over the entire circumference thereof even if the rotating shaft 4 is inclined or eccentric with respect to the shaft hole 2A. When the rotation shaft 4 is tilted or eccentric with respect to the shaft hole 2A, the slide member 24 located around the rotation shaft 4 moves following the movement of the rotation shaft 4. The seal lips 18A, 18B, and 18C are present at positions substantially fixed relative to the sliding member 24, and therefore also at positions substantially fixed relative to the rotary shaft 4. Therefore, the seal lips 18A, 18B, and 18C can contact the outer peripheral surface of the rotary shaft 4 over the entire circumference.

As described above, when the rotary shaft 4 rotates, the outer peripheral surface of the rotary shaft 4 slides against the inner peripheral surface of the sliding member 24. The sliding member 24 is made of a resin having a lower friction coefficient, such as polytetrafluoroethylene, which is harder than an elastomer. Therefore, even if the rotary shaft 4 rotates, it is possible to prevent the occurrence of abnormal noise due to friction between the outer peripheral surface of the rotary shaft 4 and the inner peripheral surface of the slide member 24.

Although not indispensable, a groove 24A for retaining grease is formed on the inner circumferential surface of the sliding member 24. The grease further reduces friction between the outer circumferential surface of the rotary shaft 4 and the inner circumferential surface of the sliding member 24.

Although not indispensable, the seal portion 10 has a reinforcing ring 26 embedded in the cylindrical portion 14. The reinforcing ring 26 is formed of a rigid material, such as metal, and suppresses deformation of the cylindrical portion 14 so that the seal lips 18A, 18B, 18C can be brought into contact with the rotary shaft 4 in a stable posture.

The seal portion 40 has a similar structure to the seal portion 10. By having the double structure of the seal portions 10 and 40, the function of suppressing the transmission of sound from the space E on the engine compartment side to the space P on the passenger compartment side can be further improved, and the function of suppressing the entry of foreign matter from the space E on the engine compartment side to the space P on the passenger compartment side can be further improved.

The seal portion 40 is basically a highly elastic member made of an elastic material, such as an elastomer, and includes an annular attachment portion 42 attached to the inner peripheral surface of the shaft hole 2A, a cylindrical portion 44 disposed radially inward of the attachment portion 42, and a meandering corrugated portion 46 connecting the attachment portion 42 and the cylindrical portion 44.

Further, the seal portion 40 has a seal lip portion 48, and the seal lip portion 48 extends from the cylindrical portion 44 toward the radially inner side and toward the engine compartment-side space E, and contacts the outer circumferential surface of the rotary shaft 4 over the entire circumference. The seal lip 48 has a cylindrical shape that slidably comes into surface contact with the rotary shaft 4. The seal lip 48 is elastically deformed by contact with the rotary shaft 4. The cylindrical portion 44, the bellows portion 46 and the sealing lip portion 48 are formed of an elastic material, such as an elastomer.

In the present embodiment, although the seal lip portion 48 has a cylindrical shape, it may have 1 or more seal lips having the same shape as any one of the seal lips 18.

The mounting portion 42 has: an elastic ring 50 formed of an elastic material, for example, an elastomer; and a rigid ring 52 fixedly bonded around the elastic ring 50 and formed of a rigid material such as metal. The resilient ring 50 may be formed of the same material as the cylindrical portion 44, the bellows 46 and the sealing lip 48, in which case the resilient ring 50 is connected to the bellows 46.

The rigid ring 52 has a substantially L-shaped cross-sectional shape, and is fitted into the elastic ring 20 of the mounting portion 12 of the seal portion 10.

The bellows portion 46 is a portion that is easily elastically deformed, and is provided to allow movement, i.e., inclination and eccentricity, of the rotary shaft 4 by its elastic deformation, and the seal lip portion 48 can be in contact with the outer peripheral surface of the rotary shaft 4 over the entire circumference.

Further, the seal portion 40 has an annular slide member 54, and the annular slide member 54 is disposed inside the cylindrical portion 44 and fixed to the cylindrical portion 44. A convex portion formed on the outer peripheral surface of the slide member 54 is fitted into a concave portion formed on the inner peripheral surface of the cylindrical portion 44. The manner of coupling the slide member 54 to the cylindrical portion 44 will be described in detail later.

The sliding member 54 is provided so that the seal lip 48 can contact the outer peripheral surface of the rotating shaft 4 over the entire circumference thereof even if the rotating shaft 4 is inclined or eccentric with respect to the shaft hole 2A. When the rotation shaft 4 is tilted or eccentric with respect to the shaft hole 2A, the slide member 54 located around the rotation shaft 4 moves following the movement of the rotation shaft 4. The seal lip 48 is present at a position substantially fixed relative to the sliding member 54, and therefore is also present at a position substantially fixed relative to the rotary shaft 4. Therefore, the seal lip 48 can contact the outer peripheral surface of the rotary shaft 4 over the entire circumference.

As described above, when the rotary shaft 4 rotates, the outer peripheral surface of the rotary shaft 4 slides against the inner peripheral surface of the sliding member 54. The sliding member 54 is made of a resin having a lower friction coefficient, such as polytetrafluoroethylene, which is harder than an elastic body. Therefore, even if the rotary shaft 4 rotates, it is possible to prevent the occurrence of abnormal noise due to friction between the outer peripheral surface of the rotary shaft 4 and the inner peripheral surface of the slide member 54.

Although not indispensable, a groove 54A for retaining grease is formed on the inner circumferential surface of the sliding member 54. The grease further reduces friction between the outer circumferential surface of the rotary shaft 4 and the inner circumferential surface of the sliding member 54.

Although not provided in this embodiment, a reinforcing ring similar to the reinforcing ring 26 of the seal portion 10 may be embedded in the cylindrical portion 44. Such a reinforcing ring suppresses deformation of the cylindrical portion 44, so that the seal lip 48 can be brought into contact with the rotary shaft 4 in a stable posture.

The connection between the slide member 54 and the cylindrical portion 44 will be described in detail later.

A protruding portion 60 protruding radially inward is formed at the end of the cylindrical portion 44 on the passenger compartment side. As shown in fig. 2 in an enlarged scale, the projection 60 has 2 parallel surfaces orthogonal to the rotation axis 4.

Fig. 3 is a bottom view of the cylindrical portion 44 and the slide member 54, specifically, as seen from the space P on the passenger compartment side. As shown in fig. 3, in the present embodiment, the protruding portion 60 is an annular protrusion that is continuous in the circumferential direction.

On the other hand, as shown in an enlarged view in fig. 2, a circumferential groove 62 is formed in the outer circumferential surface of the slide member 54, and the circumferential groove 62 has a cylindrical bottom circumferential surface and 2 side wall surfaces orthogonal to the bottom circumferential surface. The projection 60 is fitted into the circumferential groove 62, and 2 surfaces of the projection 60 are in contact with 2 side wall surfaces of the circumferential groove 62, respectively. Therefore, the slide member 54 is reliably coupled to the cylindrical portion 44, and the coupling is stable. Therefore, even if the rotary shaft 4 is eccentric with respect to the housing 2 or inclined as shown in fig. 2, the seal lip 48 is continuously in contact with the outer peripheral surface of the rotary shaft 4 over the entire circumference.

Further, an expanded portion 64 expanded radially outward and a hook portion 66 extending in the axial direction from the outer edge of the expanded portion are formed at the end of the slide member 54. The expanded portion 64 and the hook portion 66 are coaxially formed in the protrusion 60 and the circumferential groove 62. As shown in fig. 3, in the present embodiment, the expanded portion 64 is a flange continuous in the circumferential direction, and the hook portion 66 is a cylinder continuous in the circumferential direction. Therefore, the expanded portion 64 is a side wall on one side of the circumferential groove 62, and the hook portion 66 overlaps the circumferential groove 62 in the radial direction.

On the other hand, as shown in an enlarged view in fig. 2, an end surface peripheral groove 68 and an annular projecting wall 69 are formed on the end surface of the cylindrical portion 44. An annular convex wall 69 is formed around the end face peripheral groove 68 coaxially with the protrusion 60 and the peripheral groove 62.

The end surface peripheral groove 68 is disposed radially outward of the protruding portion 60 and overlaps the protruding portion 60 in the radial direction. In this way, the hook portion 66 of the end portion of the slide member 54 and the end face circumferential groove 68 of the cylindrical portion 44 are arranged radially outward of the circumferential groove 62 of the slide member 54 and the protruding portion 60 of the cylindrical portion 44. A hook portion 66 at the end of the slide member 54 is fitted in an end surface peripheral groove 68 of the cylindrical portion 44. Therefore, the connection between the circumferential groove 62 of the slide member 54 and the protruding portion 60 of the cylindrical portion 44 is difficult to release. Therefore, the slide member 54 and the cylindrical portion 44 are further reliably coupled, and the coupling is further stabilized.

Fig. 4 is an enlarged view of a part of the seal portion 40 of the comparative example in which the rotary shaft 4 is inclined. In the present comparative example, the protruding portion 60 and the end face peripheral groove 68 are not formed in the cylindrical portion 44, and the peripheral groove 62, the expanded portion 64, and the hook portion 66 are not formed in the slide member 54. The sliding member 54 is coupled to the cylindrical portion 44 only by fitting a convex portion formed on the outer peripheral surface of the sliding member 54 into a concave portion formed on the inner peripheral surface of the cylindrical portion 44.

In the comparative example, the coupling strength between the sliding member 54 and the cylindrical portion 44 is insufficient, and the cylindrical portion 44 is slightly separated from the sliding member 54 on the left side in fig. 4. That is, on the left side of fig. 4, the cylindrical portion 44 is not firmly supported by the slide member 54. Therefore, the seal lip 48 cannot follow the inclination of the rotary shaft 4, but is away from the rotary shaft 4. In contrast, in the embodiment, the cylindrical portion 44 is firmly supported over the entire circumference by the sliding member 54, and the seal lip 48 is continuously in contact with the outer circumferential surface of the rotary shaft 4 over the entire circumference.

Fig. 5 is a bottom view of the cylindrical portion 44 and the sliding member 54 of the sealing device 1 according to the modification of the first embodiment, and specifically, is a view seen from the space P on the passenger compartment side, as in fig. 3.

In the present modification, the protruding portion 60 protruding radially inward of the cylindrical portion 44 has a plurality of protrusions 60A arranged at intervals in the circumferential direction, instead of the annular protrusion that continues in the circumferential direction. The projections 60A of the projections are equally spaced, but may be unequally spaced. The number of the projections 60A of the projection is not limited to the illustrated one.

As shown in fig. 2, these projections 60A are fitted into a circumferential groove 62 formed in the outer circumferential surface of the slide member 54, and 2 surfaces orthogonal to the rotation axis 4 of each projection 60A are in contact with 2 side wall surfaces of the circumferential groove 62. In this modification, the cross-sectional view of fig. 2 is common to the first embodiment. In fig. 2, the projection 60 is referred to as a projection 60A instead.

In the present modification, the sliding member 54 and the cylindrical portion 44 are also reliably coupled, and the coupling is stable. Therefore, even if the rotary shaft 4 is eccentric with respect to the housing 2 or inclined as shown in fig. 2, the seal lip 48 is continuously in contact with the outer peripheral surface of the rotary shaft 4 over the entire circumference.

In the present modification, the plurality of projections 60A arranged at intervals in the circumferential direction, instead of the annular projection continuous in the circumferential direction, are fitted into the circumferential groove 62 formed in the outer circumferential surface of the slide member 54, so that the projection 60 and the circumferential groove 62 can be easily connected as compared with the first embodiment.

In the present modification, the expanded portion 64 at the end of the slide member 54 has a plurality of protrusions 64A arranged at intervals in the circumferential direction instead of a flange continuous in the circumferential direction, and the hook portion 66 has a plurality of segments 66A arranged at intervals in the circumferential direction instead of a cylinder continuous in the circumferential direction. The intervals of the projections 64A of the expansion portion are equal, but may be unequal. The number of the projections 64A of the expansion portion is not limited to the illustrated one. The hook segments 66A may be equally spaced apart, although they may be equally spaced apart. The number of hook segments 66A is not limited to that shown.

In fig. 2, the expanded portion 64 is instead referred to as a projection 64A, and the hook portion 66 is instead referred to as a fragment 66A. The projection 64A of the expanded portion constitutes a side wall on one side of the circumferential groove 62, and the hook portion piece 66A overlaps the circumferential groove 62 in the radial direction. Hook-portion segments 66A at the end of the slide member 54 are fitted into end-face circumferential grooves 68 of the cylindrical portion 44. Therefore, the connection between the circumferential groove 62 of the slide member 54 and the protruding portion 60 of the cylindrical portion 44 is difficult to release. Therefore, the slide member 54 and the cylindrical portion 44 are further reliably coupled, and the coupling is further stabilized.

In the present modification, since the plurality of segments 66A, which are not circumferentially continuous cylinders but are circumferentially spaced apart, are fitted into the end surface circumferential groove 68 of the cylindrical portion 44, the hook portion 66 and the end surface circumferential groove 68 can be easily connected as compared with the first embodiment.

In the present modification, the protruding portion 60 has a plurality of projections 60A, the expanded portion 64 has a plurality of projections 64A, and the hook portion 66 has a plurality of fragments 66A. However, any one or both of the protrusion 60, the expanded portion 64, and the hook 66 may be continuous in the circumferential direction.

Second embodiment

Fig. 6 is an enlarged cross-sectional view of the seal portion 40 of the sealing device according to the second embodiment showing the inclination of the rotary shaft 4. In the drawings of fig. 6 and later, the same reference numerals are used to show the same components as those already described, and detailed description thereof will not be given.

In the second embodiment, the expanded portion 64 formed at the end of the sliding member 54 is expanded radially outward more greatly than the expanded portion 64 of the first embodiment, and is in contact with the annular projecting wall 69 of the end surface of the cylindrical portion 44.

The slide member 54 also has an outboard hook 70. The outer hook 70 extends in the axial direction from the outer end edge of the expanded portion 64, and is disposed coaxially with the hook 66 on the radially outer side of the hook 66. The outside hook portion 70 contacts the outer peripheral surface of the annular projecting wall 69 of the cylindrical portion 44.

The seal portion 40 of the second embodiment has the features of the seal portion 40 of the first embodiment, and the effects associated with the first embodiment can be achieved.

Further, according to the second embodiment, the outer hook portion 70 formed at the end portion of the slide member 54 is in contact with the outer peripheral surface of the cylindrical portion 44 except that the protruding portion 60 on the inner side of the cylindrical portion 44 is fitted in the peripheral groove 62 on the outer peripheral surface of the slide member 54. That is, the inner peripheral surface of the cylindrical portion 44 is in contact with the outer peripheral surface of the slide member 54, and the outer peripheral surface of the cylindrical portion 44 is in contact with the outer hook portion 70 of the slide member 54, so that the end portion of the cylindrical portion 44 is fitted into the end portion of the slide member 54. Therefore, the slide member 54 and the cylindrical portion 44 are further reliably coupled, and the coupling is further stabilized.

Fig. 7 is a bottom view of the cylindrical portion 44 and the sliding member 54 in the second embodiment, specifically, a view seen from the space P on the passenger compartment side. As shown in fig. 7, in the present embodiment, the protruding portion 60 is an annular protrusion that is continuous in the circumferential direction, the expanded portion 64 is a flange that is continuous in the circumferential direction, and the hook portion 66 is a cylinder that is continuous in the circumferential direction. The outer hook 70 is a cylinder continuous in the circumferential direction.

As shown in fig. 8, the expanded portion 64 may have a plurality of protrusions 64A arranged at intervals in the circumferential direction on the radially outer side, and the outer hook portion 70 may have a plurality of segments 70A arranged at intervals in the circumferential direction. The intervals between the outer hook segments 70A are equal, but may be unequal. The number of outside hook segments 70A is not limited to that shown. In the modification of fig. 8, since the plurality of segments 70A arranged at intervals in the circumferential direction, rather than being continuous in the circumferential direction, are arranged outside the cylindrical portion 44, the outer hook portion 70 can be easily connected to the cylindrical portion 44 as compared with the first embodiment.

In the second embodiment, the protruding portion 60 may have a plurality of protrusions 60A. The hook 66 may have a plurality of segments 66A.

Third embodiment

Fig. 9 shows a sealing device 1 according to a third embodiment of the present invention. In this sealing device 1, the position and shape of the mounting portion 12 of the sealing portion 10 are different from those of the mounting portion 12 of the sealing portion 10 of the first embodiment. The position and shape of the mounting portion 42 of the seal portion 40 are different from those of the mounting portion 42 of the seal portion 40 of the first embodiment.

Further, the orientations of the seal lip portion 48 and the slide member 54 with respect to the cylindrical portion 44 are opposite to the orientations of the seal lip portion 48 and the slide member 54 with respect to the cylindrical portion 44 in the first embodiment. That is, the seal lip portion 48 extends from the cylindrical portion 44 toward the radially inner side and toward the passenger compartment side space P, and the slide member 54 is disposed in a recessed portion formed in the inner peripheral surface of the engine compartment side end portion of the cylindrical portion 44.

As shown in fig. 10, in the present embodiment, a protruding portion 60 and an end face peripheral groove 68 are formed at the engine compartment-side end portion of the cylindrical portion 44, and a peripheral groove 62, an expanded portion 64, a hook portion 66, an annular projecting wall 69, and an outer hook portion 70 are formed at the engine compartment-side end portion of the slide member 54. That is, the present embodiment is different from the second embodiment in which these components are provided on the occupant compartment side of the cylindrical portion 44 and the cylindrical portion 44, by providing these components on the engine compartment side of the cylindrical portion 44 and the cylindrical portion 44. The description of the constituent elements and the modified examples related to the second embodiment are also applied to the third embodiment.

Other modifications

While the present invention has been described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. Such alterations, changes, and modifications are intended to be included within the scope of the invention.

For example, in the above embodiment, the sealing portion 40 improves the reliability of the connection between the cylindrical portion 44 and the sliding member 54, but in order to improve the reliability of the connection between the cylindrical portion 14 and the sliding member 24 in the other sealing portion 10, a similar component to the sealing portion 40 may be provided.

The slide members 24 and/or 54 may be reinforced with a rigid ring.

A known sound-insulating ring disclosed in japanese patent laid-open publication nos. 2019 and 7552 may be provided around the rotary shaft 4. The sound insulating ring can be disposed between the seal portion 10 and the seal portion 40, for example.

The embodiments of the present invention are also described in the items numbered below.

Item 1. a sealing device for closing a gap between a housing and a rotating shaft disposed in a shaft hole of the housing, comprising:

an annular mounting portion mounted on an inner peripheral surface of the shaft hole;

a cylindrical portion disposed radially inward of the mounting portion;

a seal lip portion extending from the cylindrical portion and contacting an outer circumferential surface of the rotary shaft;

a bellows portion connecting the mounting portion and the cylindrical portion; and

a resin annular sliding member disposed radially inward of the cylindrical portion and adapted to slide on an outer peripheral surface of the rotating shaft,

the cylindrical portion, the seal lip portion, and the bellows portion are formed of an elastic material having elasticity greater than that of the resin,

the cylindrical portion has a protruding portion protruding radially inward, the protruding portion being an annular protrusion continuous in the circumferential direction or having a plurality of protrusions arranged at intervals in the circumferential direction, the protruding portion having 2 surfaces orthogonal to the rotation axis,

a circumferential groove having a cylindrical bottom circumferential surface and 2 side wall surfaces orthogonal to the bottom circumferential surface is formed on an outer circumferential surface of the sliding member,

the protrusion is fitted into the circumferential groove, and 2 surfaces of the protrusion are in contact with 2 side wall surfaces of the circumferential groove, respectively.

Item 2. the sealing device according to item 1, characterized in that,

at an end of the sliding member, there are formed: an expanding portion expanding radially outward; and a hook portion extending in an axial direction from the expanding portion,

the expansion part is a flange continuous along the circumferential direction or is provided with a plurality of projections arranged at intervals along the circumferential direction,

the hook part is a cylinder which is continuous along the circumferential direction or is provided with a plurality of fragments which are arranged at intervals along the circumferential direction and are overlapped with the circumferential groove in the radial direction,

the protruding portion is formed at an end portion of the cylindrical portion,

an end surface circumferential groove that radially overlaps with the protruding portion is formed on an end surface of the cylindrical portion on a radially outer side of the protruding portion,

the hook portion of the slide member is fitted in the end surface peripheral groove.

According to this item, the hook portion at the end portion of the sliding member and the end face circumferential groove of the cylindrical portion are disposed radially outward of the circumferential groove of the sliding member and the protruding portion of the cylindrical portion, and the hook portion at the end portion of the sliding member is fitted into the end face circumferential groove of the cylindrical portion, whereby the coupling between the circumferential groove of the sliding member and the protruding portion of the cylindrical portion is difficult to release. Therefore, the sliding member and the cylindrical portion are further reliably coupled, and the coupling is further stabilized.

Item 3. the sealing device according to item 1 or 2, characterized in that,

at an end of the sliding member, there are formed: an expanding portion that expands radially outward and contacts an end surface of the cylindrical portion; and an outside hook portion extending in an axial direction from the expanded portion,

the expansion part is a flange continuous along the circumferential direction or is provided with a plurality of projections arranged at intervals along the circumferential direction,

the outer hook part is a cylinder which is continuous along the circumferential direction or is provided with a plurality of fragments which are arranged at intervals along the circumferential direction,

the outside hook portion is in contact with an outer peripheral surface of the cylindrical portion.

According to this item, the outer hook portion formed at the end of the sliding member is in contact with the outer peripheral surface of the cylindrical portion, except that the protruding portion on the inner side of the cylindrical portion is fitted in the peripheral groove of the outer peripheral surface of the sliding member. That is, the inner peripheral surface of the cylindrical portion is in contact with the outer peripheral surface of the sliding member, and the outer peripheral surface of the cylindrical portion is in contact with the outer hook portion of the sliding member, so that the end portion of the cylindrical portion is fitted into the end portion of the sliding member. Therefore, the sliding member and the cylindrical portion are further reliably coupled, and the coupling is further stabilized.

Description of the reference numerals

1 sealing device

2 casing (front dashboard)

2A axle hole

4 rotating shaft (steering shaft)

10. 40 sealing part

42 mounting part

44 cylindrical part

46 corrugated part

48 sealing lip

50 elastic ring

52 rigid ring

54 sliding member

60 projection

Projection of 60A projection

62 circumference groove

64 expansion part

Projection of 64A expansion part

66 hook part

Segments of 66A hook

68 end face peripheral groove

69 annular convex wall

70 outside hook

70A outside hook segment