JP2001001912A - Combining structure of steering column bearing with cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent influence on the rotation of a steering column shaft by preventing into a sliding surface further penetration of dust, rainwater, mud and the like which are penetrated into the inside of a housing without having influence on the operation of a universal joint. SOLUTION: The outer bush 11 of a bearing 2 for a steering column in which an elastic cover 3 is arranged in one end part is equipped with an inner ring 13 and an outer ring 14 concentric with the inner ring 13, the inner ring 13 is equipped with a lip part which is projected radially inward in one end part of the inner circumferential surface of an inner ring body and a locking projected groove part which is axially spaced at a required interval from the lip part, projected radially inward and sections a cylindrical recessed part by being incorporated with the inner circumferential surface of the inner ring body, and an inner bush 12 arranged in the inside of the outer bush 11 is arranged in the cylindrical recessed part. The cover 3 is equipped with a cylindrical part, an engagement part which is formed on the inner circumferential surface of one end part of the cylindrical part and engaged with the vicinity of one end part of the peripheral surface of the inner ring body, and an annular part extended from the other end part of the cylindrical part to the radial inward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering column bearing for supporting a steering column shaft of an automobile.

[0002]

The steering column shaft of an automobile is rotatably mounted in a cylindrical housing fixed to a vehicle body. In this case, the steering column shaft is rotatably supported by the housing. For this purpose, a bearing is interposed between the steering column shaft and the housing. As such a bearing for a steering column, a plain bearing made of a synthetic resin which is inexpensive and superior in vibration absorption as compared with a ball bearing may be used.

By the way, a universal joint (universal joint) is usually attached to the lower end of the steering column shaft disposed in the housing, and the rotation of the steering column shaft is further controlled via the universal joint by a rack-pinion mechanism or the like. The lower end surface of the housing at the lower end of the steering column shaft is difficult to close due to the operation of the universal joint and remains open. I have.

Therefore, a steering column bearing interposed between the vicinity of the lower end of the steering column shaft and the housing and rotatably supporting the vicinity of the lower end of the steering column shaft on the housing is provided from the open lower end surface of the housing. It is easily affected by dust, rainwater, mud, etc. entering the housing. In particular, in the above-described sliding bearing, if such dust, rainwater, mud, etc. enters or adheres to the sliding surface, abnormal noise may be generated. Then, there is an inconvenience that the specific effect is reduced early.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to prevent dust, rainwater, mud, or the like entering a housing without affecting the operation of a universal joint. It is an object of the present invention to provide a combined structure capable of preventing further intrusion into a surface and not affecting rotation of a steering column shaft, and a bearing device using the structure.

[0006]

According to a first aspect of the present invention, there is provided a combination structure comprising a steering column bearing and an elastic cover disposed at one end of the steering column bearing. Here, the bearing for the steering column, the outer bush having elasticity,
An inner bush is provided in the outer bush, and the outer bush has an inner ring and an outer ring arranged concentrically with the inner ring and outside the inner ring.The inner ring has a cylindrical inner ring body and A lip portion protruding radially inward at one end of the inner peripheral surface of the inner ring main body, and a lip portion protruding radially inward from the inner peripheral surface of the inner ring main body at a predetermined distance from the lip portion in the axial direction. An inner bush is provided in the cylindrical recess, and the cover is formed of a cylindrical shape. And an engaging portion formed on the inner peripheral surface of one end of the cylindrical portion and engaged near one end of the outer peripheral surface of the inner ring main body, and at least radially inward from the other end of the cylindrical portion. And an annular portion extending therefrom.

According to the combination structure of the first aspect,
A cover having an annular portion that can come into contact with the steering column shaft is disposed at one end of the bearing for the steering column by engaging with the engagement portion near one end of the outer peripheral surface of the inner race body. Therefore, it is possible to prevent further entry of dust, rainwater, mud, etc., between the lip portion of the steering column bearing and the steering column shaft, and the steering column shaft is not affected by dust, rainwater, mud, etc. And can be freely rotatably supported over a long period of time.

In the combined structure according to the second aspect of the present invention, in the combined structure according to the first aspect, the engaging portion is provided so as to protrude radially inward on an inner peripheral surface of one end of the cylindrical portion. A projection is provided, and the projection is fitted in a recess formed in a radially inward direction near one end of the outer peripheral surface of the inner ring main body. In the vicinity of one end.

In the combined structure according to the third aspect of the present invention, in the combined structure according to the first aspect, the engaging portion is formed so as to be recessed radially outward on the inner peripheral surface of one end of the cylindrical portion. The inner ring body is provided with a recess, and the recess fits into a protrusion protruding radially outward in the vicinity of one end of the outer peripheral surface of the inner ring main body. It is engaged near one end of the surface.

In the present invention, as in the second aspect, even if the projection of the cylindrical portion is fitted into the recess of the inner race body and the cover is assembled to the steering column bearing through this fitting, Alternatively or together with this, as in the third embodiment, the recess of the cylindrical portion may be fitted to the projection of the inner race body, and the cover may be assembled to the steering column bearing through this fitting.

[0011] In the combination structure of the fourth aspect of the present invention, the combination structure of the second or third aspect may include:
The engaging portion engages with one end of the outer peripheral surface of the inner ring main body with play in the axial direction.

In the combined structure according to a fifth aspect of the present invention, in the combined structure according to any one of the second to fourth aspects, the engaging portion is formed on the outer peripheral surface of the inner race body so as to be movable in the circumferential direction. It is designed to engage near one end.

According to the combined structure of the fourth or fifth aspect, the cover is arranged at one end of the bearing for the steering column with a certain degree of freedom. The rotation of the steering column shaft is not hindered, and even if the annular portion is brought into close contact with the steering column shaft with interference, the cover is rotated with the rotation of the steering column shaft. Does not hinder rotation.

In a combined structure according to a sixth aspect of the present invention, in the combined structure according to the first aspect, the engaging portion is provided so as to protrude radially inward on an inner peripheral surface of one end of the cylindrical portion. And a projection which is engaged with an interference near one end of the outer peripheral surface of the inner ring main body.

[0015] In the combination structure of the seventh aspect of the present invention, the combination structure of the first or sixth aspect may further comprise:
The engaging portion is engaged with a protrusion protruding radially outward in the vicinity of one end of the outer peripheral surface of the inner ring main body with an interference.

According to the present invention, as in the sixth aspect, even if the projection of the cylindrical portion is engaged with the outer peripheral surface of the inner ring body with interference, and the cover is assembled to the steering column bearing through this engagement, Alternatively or together with this, as in the seventh embodiment, the engagement portion of the cylindrical portion is engaged with the protrusion of the inner ring main body with interference, and the cover is assembled to the steering column bearing through this engagement. Is also good.

In the present invention, the recesses and projections are preferably annular in shape in the circumferential direction. However, the present invention is not limited to this, and at least one of the recesses and projections is formed in the circumferential direction. It may be intermittent.

In the combined structure according to the eighth aspect of the present invention, in the combined structure according to any one of the first to seventh aspects, the cover is integrally formed on one end surface of the annular portion and is concentric with each other. And an inner cylinder part and an outer cylinder part which are arranged in the axial direction and extend in the axial direction. The inner cylinder part has an axial length shorter than the axial length of the outer cylinder part.

In the combined structure according to the ninth aspect of the present invention, in the combined structure according to any one of the first to eighth aspects, the outer bush is an annular support leg integrally connecting the inner ring and the outer ring. And at least three plate-like reinforcing ribs integrally connecting the inner ring, the outer ring, and the support legs.

[0020] In the combination structure of the tenth aspect of the present invention, in the combination structure of the ninth aspect, the outer ring comprises:
It has a cylindrical outer ring main body, and a plurality of ridges extending in the axial direction on the outer peripheral surface of the outer ring main body and arranged in the circumferential direction, and the support legs do not correspond to the cylindrical concave portions. The outer peripheral surface of the inner ring main body and the inner peripheral surface of the outer ring main body facing the outer peripheral surface are integrally connected in the circumferential direction thereof, and the reinforcing rib is formed on the outer peripheral surface of the inner ring main body with which the engaging portion is engaged. It extends from the vicinity of the part along the axial direction to the support leg, and integrally connects the outer peripheral surface of the inner ring main body, the inner peripheral surface of the outer ring main body, and the support leg.

According to the combination structure of the tenth aspect,
Since the outer peripheral surface of the inner ring main body not corresponding to the cylindrical concave portion and the inner peripheral surface of the outer ring main body facing the outer peripheral surface are integrally connected in the circumferential direction by the support legs, the pressure at the time of press-fitting and fixing to the housing is reduced. The input can be prevented from directly acting on the cylindrical recess, and the inner diameter dimensional accuracy (roundness) of the inner bush held in the cylindrical recess is not affected. In addition, even if the influence of welding strain due to welding processing adversely affects the inner diameter dimensional accuracy (roundness) of the housing,
Since the deviation in the dimensional accuracy of the inner diameter of the housing does not directly act on the cylindrical concave portion of the inner ring, the inner dimensional accuracy (roundness) of the inner bush held in the cylindrical concave portion is not affected.

A bearing device for a steering column according to the present invention includes the combined structure according to any one of the first to tenth aspects, wherein the steering column bearing has a cylindrical structure on an outer peripheral surface of an outer ring. The steering column shaft, which is press-fitted into the housing, is slidably in contact with the lip portion with a tightening margin, and is supported while maintaining a predetermined bearing clearance with the inner peripheral surface of the inner bush. And the inner peripheral surface of the annular part of the cover,
The lip portion penetrates through the inner ring body and contacts the steering column shaft projecting from the inner ring body to the outside with interference.

According to the bearing device for a steering column of the present invention, the inner peripheral surface of the annular portion of the cover penetrates through the inner race body and comes into contact with the steering column shaft protruding from the inner race body to the outside at the lip side with interference. Therefore, as described in the combined structure of the first aspect, it is possible to prevent further entry of dust, rainwater, mud, etc., between the lip portion of the steering column bearing and the steering column shaft. Thus, the steering column shaft can be freely rotatably supported for a long period of time without being affected by dust, rainwater, mud and the like.

In the above combined structure and the bearing device for a steering column, the lip portion and the locking ridge portion of the inner race of the outer bush are each provided with an annular lip extending continuously along the circumferential direction of the inner race. It may be a portion and a locking ridge portion, or may be a plurality of portions arranged intermittently (intermittently) in the inner ring along the circumferential direction. In one preferred example, the lip is
The diameter of an imaginary circle formed at the tip of the lip (the inner diameter of the lip in the present invention) is formed to be smaller than the inner diameter of the inner bush by about 0.02 mm to 0.20 mm.

As the material for forming the outer bush having elasticity, a rubber elastic body or a synthetic resin having elasticity can be exemplified. The synthetic resin having elasticity is soft and tough, and is generally a shore. Hardness (D type) 4
0-60, rebound resilience value (JIS-K6301) 50-
It has a rubber-like elastic behavior of 80, and is preferably a polyester-ether copolymer or a polyurethane.

As a material for forming the cover having elasticity,
A rubber elastic body equivalent to the outer bush, a synthetic resin having elasticity can be exemplified, but in order to further improve the sealing property, a rubber containing a synthetic elastomer, a polyester elastomer slightly softer than the material forming the outer bush, Preferable examples include forming materials such as elastic materials and polyurethane.

Hereinafter, embodiments of the present invention will be described in detail based on preferred examples shown in the drawings. The present invention is not limited to these examples.

[0028]

1 to 3, a steering column bearing device 1 of this embodiment includes a steering column bearing 2 and an elastic cover 3 disposed at one end of the steering column bearing 2. Is provided.

The steering column bearing 2 comprises an elastic outer bush 11 made of a rubber elastic body or an elastic synthetic resin, and an inner bush 12 inserted and held in the outer bush 11. The outer bush 11 includes an inner race 13 and an inner race 13.
An outer ring 14 arranged concentrically with the outside of the inner ring 13, an annular support leg 15 connecting the outer ring 14 and the inner ring 13 so that the outer ring 14 supports the inner ring 13, and a reinforcement of the inner ring 13. , And at least three, in this example, six, reinforcing ribs 16 in which the inner race 13, the outer race 14, and the support legs 15 are integrally connected.

The inner ring 13 has a cylindrical inner ring main body 21 and a plurality of, in this embodiment, six lip portions 23 projecting radially inward at one end of an inner peripheral surface 22 of the inner ring main body 21. And a radially inwardly projecting inner circumferential surface 22 of the inner race body 21 which is spaced from the lip 23 by a predetermined distance in the axial direction.
And a locking ridge 25 extending in a circumferential direction in an annular manner to define a cylindrical recess 24 in cooperation with the inner peripheral surface 22.
The inner diameter d1 of the lip portion 23 (referred to as the diameter of an imaginary circle formed by the tip surface of the lip portion 23) is
Is formed to be slightly smaller than the inner diameter d2.

The outer race 14 has a cylindrical outer race main body 31 and a plurality of ridges (serrations) 33 extending along the axial direction on the outer peripheral surface 32 of the outer race main body 31 and arranged in the circumferential direction.
And an annular flange 35 extending radially outward at one end 34 of the outer race main body 31. Note that the annular flange 35 may be omitted, and the ridge 33 may be formed on the entire outer peripheral surface 32 of the outer ring main body 31.

The support leg 15 integrally connects the outer peripheral surface 35 of the inner race main body 21 that does not correspond to the cylindrical concave portion 24 and the inner peripheral surface 36 of the outer race main body 31 facing the outer peripheral surface 35 in the circumferential direction. I have.

The reinforcing ribs 16 extend from the vicinity of the recess 41 formed in the outer peripheral surface 35 of the inner ring body 21 where the engaging portion 54 to be described later engages to the support leg 15 along the axial direction. The outer peripheral surface 35 of the inner ring main body 21, the inner peripheral surface 36 of the outer ring main body 31, and the side surface 42 of the support leg 15 are integrally connected. The reinforcing ribs 16 reinforce the inner ring main body 21 at a portion where the cylindrical concave portion 24 is formed.
Although this arrangement is provided, three or more arrangements may be provided at equal intervals in the circumferential direction.

The inner bush 12 is held in the cylindrical recess 24 between the lip portion 23 and the locking ridge portion 25. In this embodiment, the inner bush 12 is formed integrally with a thin steel plate on the surface of the thin steel plate. It consists of a three-layer structure of a metal sintered layer and a synthetic resin layer impregnated and coated on this metal sintered layer, and is formed of a so-called wound bush formed by winding the synthetic resin layer inside and forming a cylindrical shape. I have.

In the steering column bearing 2 assembled by inserting the inner bush 12 into the cylindrical recess 24 of the inner race 13, the plurality of lip portions 23
The inner bush 12 is formed so as to protrude inward in the radial direction with an inner diameter d1 slightly smaller than the inner diameter d2. Specifically, the inner diameter d1 of the lip portion 23 is smaller than the inner diameter d2 of the inner bush 12 by the inner bush 12 and the inner bush. An amount corresponding to a clearance (sliding gap) between the large-diameter portion 46 of the steering column shaft 45 supported by the bush 12, for example, 0.02 mm to 0.20 m
It is formed to be smaller by m. The locking ridge 25 is formed so that its inner diameter d3 is larger than the inner diameter d2 of the inner bush 12 and smaller than the outer diameter d4. Therefore, the inner bush 12 is inserted and held in the cylindrical concave portion 24 of the inner race 13, so that the inner bush 12 is prevented from coming off from the inner race 13.

The cover 3 includes a circular cylindrical portion 51 and a cylindrical portion 51.
The shaft 41 has a recess 41 protruding radially inward from the inner peripheral surface 53 of the one end 52 of the inner ring body and radially inwardly recessed near one end of the outer peripheral surface 35 of the inner race body 21. Engagement portion 54 having an annular projection fitted so as to be able to move in the circumferential direction with some play in the direction, and an annular portion 56 extending radially inward from the other end 55 of the cylindrical portion 51. And an inner cylindrical portion 58 and an outer cylindrical portion 59 which are integrally formed on one end face 57 of the annular portion 56 and are concentrically arranged and extend in the axial direction.

The inner peripheral surface 60 of the annular portion 56 has an inner diameter d5.
Is formed to be slightly smaller than the diameter of the large diameter portion 46 of the steering column shaft 45 so as to come into close contact with the large diameter portion 46 of the steering column shaft 45. The inner cylindrical portion 58 has an axial length shorter than the axial length of the outer cylindrical portion 59, and each of the inner cylindrical portion 58 and the outer cylindrical portion 59 is provided with a forked yoke 6 of the steering column shaft 45.
5 have inclined surfaces 71 and 72 which come into close contact with the outer peripheral surface. The inner tube portion 58 and the outer tube portion 59 are for positioning the cover 3. If the cover 3 can be positioned as desired by another configuration, the inner tube portion 58 and the outer tube portion 59 are omitted. Is also good.

In the bearing device 1 for a steering column, the bearing 2 for the steering column includes a cylindrical housing 75 on the outer peripheral surface of the outer race 14, that is, the ridge 33.
The steering column shaft 45 disposed in the housing 75 integrally includes the small diameter portion 73, the large diameter portion 46, and the forked yoke 65, and is in sliding contact with the lip portion 23 with an interference. The inner bush 12 is supported while maintaining a predetermined bearing clearance with the inner peripheral surface 76 of the inner bush 12. The inner peripheral surface 60 of the annular portion 56 of the cover 3 is
The large-diameter portion 46 of the steering column shaft 45 that penetrates through the first and protrudes outside from the inner race body 21 on the lip portion 23 side
Is in contact with the deadline. The steering column bearing 2 is firmly fixed to the housing 75 by a caulking portion 81 formed by caulking the housing 75 from the outside so as not to come out of the housing 75, and the housing 75 is fixed to a vehicle body or the like. Have been.

In the steering column bearing device 1 described above, the lower end surface 82 of the housing 75 is normally opened because the universal joint is attached to the forked yoke 65. Even if dust, rainwater, mud, or the like enters the vehicle, the inner peripheral surface 60 of the annular portion 56 of the cover 3
5 is in close contact with the large-diameter portion 46, so that invading dust, rainwater, mud, and the like are further increased by the large-diameter portion 46 and the lip portion 23.
And the sliding surface between the inner bush 12 and the inner bush 12 can be prevented, and there is no possibility that the dust, rainwater, mud, or the like will deteriorate the function of the steering column bearing 2.

Further, in the bearing device 1 for a steering column, since the inner race 13 is integrally connected to the outer race 14 via the support leg 15, the bearing 2 is press-fitted into the housing 75 in the cylindrical recess 24 of the inner race 13. Since the pressing force at the time of the pressing does not directly act, the inner diameter dimensional accuracy (roundness) of the inner bush 12 inserted and held in the cylindrical concave portion 24 is not affected. Therefore, an appropriate clearance (sliding gap) is maintained between the inner bush 12 and the large-diameter portion 46 of the steering column shaft 45 supported by the inner bush 12, so that the smoothness can be achieved without causing a problem such as a one-side contact. Sliding takes place.

Further, the influence of the press-in force is
2 as well as the lip portion 2 of the inner ring 13
3, the interference of the lip portion 23 with the large-diameter portion 46 of the steering column shaft 45 is also not affected by the press-in force. Slidably and resiliently.

In the above combined structure 4, the inner cylinder 5
8 and the cover 3 having the outer tube portion 59, but instead of this, as shown in FIG.
9 may be used, and the cover 85
Is protruded radially inward from a circular cylindrical portion 86 and an inner peripheral surface 88 of one end portion 87 of the cylindrical portion 86, and is recessed near one end of the outer peripheral surface 35 of the inner race body 21. An engagement portion 89 having an annular projection fitted into the recess 41 so as to be able to move in the axial direction with a little play in the axial direction, and
An annular inner peripheral surface 91 similar to the inner peripheral surface 60 that extends radially inward and outward from the other end portion 90 of the cylindrical portion 86 and is in tight contact with the large-diameter portion 46 of the steering column shaft 45.
And an annular portion 92 having

In the combined structure 4 of the cover 85 and the steering column bearing 2 shown in FIG.
Dust, rainwater, mud, and the like that have entered the housing 75 can be further prevented from entering the sliding surface between the large-diameter portion 46 and the lip portion 23 and the inner bush 12. There is no possibility that the function of the steering column bearing 2 is reduced.

Further, in the above description, the engaging portion 54 or 89 having a projection protruding from the inner peripheral surface 53 or 88 of the cylindrical portion 51 or 86 is formed. Instead of this, as shown in FIG. 6, the engagement portion 9 is provided with a recess formed in the inner peripheral surface 88 of the cylindrical portion 86.
5 and the engaging portion 95 is fitted to a projection 96 projecting radially outward in the vicinity of one end of the outer peripheral surface 35 of the inner race main body 21 to form the engaging portion 95. The outer peripheral surface 35 of the inner ring main body 21 may be engaged near one end of the outer peripheral surface 35 of the inner ring main body 21. Further, as shown in FIG.
The inner peripheral surface 8 of the cylindrical portion 86 can be formed without providing a recess or a projection.
8 is provided with an engagement portion 89 having a projection protruding from the inner ring main body 2.
7 may be engaged with the outer peripheral surface 35 of the inner ring main body 21 without providing a projection or a recess on the inner peripheral surface 88 of the cylindrical portion 86, contrary to FIG. Figure 6
And a projection 96 shown in FIG.
6, the inner peripheral surface 88 may be used as an engaging portion. In addition, as the engaging portion, the above examples may be combined with each other.

[0045]

According to the present invention, it is possible to prevent dust, rainwater, mud and the like from entering the housing from further entering the sliding surface without affecting the operation of the universal joint. It is possible to provide a combined structure capable of preventing the rotation of the shaft from being affected and a bearing device using the combined structure.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a preferred embodiment of the present invention.

FIG. 2 is an exploded cross-sectional view of the combination structure used in the example shown in FIG.

FIG. 3 is a view taken along line III-III shown in FIG. 2;

FIG. 4 is a view taken along the line IV-IV shown in FIG. 2;

FIG. 5 is an exploded cross-sectional view of another example of the combination structure that can be used in the example shown in FIG. 1;

FIG. 6 is a partially enlarged cross-sectional view of another example of the combination structure that can be used in the example shown in FIG. 1;

FIG. 7 is a partially enlarged sectional view of still another example of the combination structure that can be used in the example shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 2 Steering column bearing 3 Cover 4 Combined structure 11 Outer bush 12 Inner bush 13 Inner ring 14 Outer ring 21 Inner ring main body 23 Lip part 25 Locking ridge 41 Depression 51 Tube part 54 Engagement part

Continued on front page F-term (reference) 3D030 DC35 DC37 3J012 AB07 AB13 BB01 DB07 DB13 EB05 FB01 3J016 AA02 BB03

Claims (11)

[Claims] 1. A steering column bearing comprising: a steering column bearing; and an elastic cover disposed at one end of the steering column bearing. The steering column bearing includes an elastic outer bush, an outer bush, and an outer bush; An inner bush disposed in the bush, the outer bush includes an inner ring, and an outer ring disposed concentrically with the inner ring and outside the inner ring, wherein the inner ring has a cylindrical inner ring body; A lip protruding radially inward at one end of the inner peripheral surface of the inner ring main body, and a lip protruding radially inward from the inner peripheral surface of the inner ring main body at a predetermined distance from the lip in the axial direction. And a locking ridge that defines a cylindrical recess in cooperation with the lip portion and the inner peripheral surface of the inner ring body, the inner bush is disposed in the cylindrical recess, and the cover is
A tubular portion, an engaging portion formed on the inner peripheral surface of one end of the tubular portion and engaging near one end of the outer peripheral surface of the inner ring body, and at least radially inward from the other end of the tubular portion. A combined structure of a steering column bearing and a cover, comprising an annular portion extending in a direction. 2. The engagement portion has a projection radially inwardly protruding from an inner peripheral surface of one end of the cylindrical portion, and the projection is located near one end of an outer peripheral surface of the inner ring main body. By fitting into the recess formed in the radially inward direction, the engaging portion is
The combination structure according to claim 1, wherein the combination structure is engaged near one end of the outer peripheral surface of the inner ring main body. 3. The engaging portion has a recess radially outwardly formed on an inner peripheral surface of one end portion of the cylindrical portion, and the concave portion is provided at one end of an outer peripheral surface of the inner ring main body. By engaging with a protrusion protruding radially outward in the vicinity of the part, the engaging part is
The combination structure according to claim 1, wherein the combination structure is engaged near one end of the outer peripheral surface of the inner ring main body. 4. The combination structure according to claim 2, wherein the engaging portion engages with one end of the outer peripheral surface of the inner ring body with play in the axial direction. 5. The engagement part according to claim 2, wherein the engagement part is engaged with one of the outer peripheral surfaces of the inner race body in the vicinity of one end so as to be movable in the circumferential direction. Combination structure. 6. An engagement portion is provided with a projection protruding radially inward on an inner peripheral surface of one end portion of the cylindrical portion, and engaging with one end near an outer peripheral surface of the inner ring body with an interference. The combination structure according to claim 1, comprising: 7. The combination according to claim 1, wherein the engaging portion is engaged with a protrusion projecting radially outward in the vicinity of one end of the outer peripheral surface of the inner race body with a interference. Structure. 8. The cover further includes an inner cylindrical portion and an outer cylindrical portion formed integrally with one end surface of the annular portion and arranged concentrically with each other and extending in the axial direction. And an axial length shorter than the axial length of the outer cylindrical portion.
The combination structure according to any one of the above. 9. The outer bush further includes an annular support leg connecting the inner ring and the outer ring, and at least three plate-like reinforcing ribs connecting the inner ring, the outer ring, and the support leg. 9. The combination structure according to any one of 1 to 8. 10. The outer ring includes a cylindrical outer ring main body, and a plurality of ridges extending in an axial direction on an outer peripheral surface of the outer ring main body and arranged in a circumferential direction. The legs integrally connect the outer peripheral surface of the inner ring main body not corresponding to the cylindrical concave portion and the inner peripheral surface of the outer ring main body facing the outer peripheral surface in the circumferential direction thereof. The support leg extends along the axial direction from the vicinity of the portion of the outer peripheral surface of the inner ring main body to the supporting leg, and integrally connects the outer peripheral surface of the inner ring main body, the inner peripheral surface of the outer ring main body, and the support leg. The combination structure as described. 11. A steering column bearing device provided with the combined structure according to claim 1, wherein the steering column bearing is provided in a cylindrical housing on an outer peripheral surface of an outer ring. The steering column shaft, which is press-fitted and disposed in the housing, is slidably contacted with the lip portion with a tightening margin and is supported while maintaining a predetermined bearing clearance with the inner peripheral surface of the inner bush. A bearing device for a steering column in which an inner peripheral surface of the portion is in contact with a steering column shaft which penetrates the inner race body and protrudes outside from the inner race body on the lip side.