JP2001114119A - Method for fixing bearing bush inside of steering shaft support element and bearing bush used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of fixing a bearing bush to a hole of a steering shaft support element without being much influenced by the dimension al error of the hole of the steering shaft support element, with the dimensional error of the bearing bush thickness corrected, and with a high inner diameter dimensional accuracy. SOLUTION: This method for fitting the bearing bush 4 inside of the steering shaft support elements 11 has a process in which a part of a cylindrical outer surface 33 of a core 31 is fitted into the hole 7 of the steering shaft support element 11, a cylindrical outer surface 35 of the core 31 is fitted into a bearing bush fitting hole 2 of the steering shaft support element 11, and the bearing bush 4 is fixed in a cylindrical inner wall surface 1 for fitting the bearing bush 4 by upsetting the bearing bush 4 by the remainder of the cylindrical outer surface 33 and an each annular surface 39 of the steering shaft support element 11 and the core 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of fixing a bearing bush to a steering shaft support for rotatably supporting a steering input shaft or a steering column shaft of a vehicle such as an automobile via a bearing bush. The present invention relates to a bearing bush for use in the method.

[0002]

An automobile steering apparatus includes a steering wheel and a steering valve mechanism for transmitting rotation of the steering wheel to a rack and pinion gear mechanism. For steering, it usually comprises a hollow steering input shaft and a torsion bar mounted in the steering input shaft, the torsion bar being fixed at one end to the steering input shaft. At the other end, the pinion gear of the rack and pinion gear mechanism is fixed to a integrally formed steering shaft support, and the steering input shaft is
At one end, it is connected to a steering wheel, and at the other end, it is rotatably supported by a steering shaft support.

In order to support the steering input shaft on the steering shaft support so as to be freely rotatable, a rolling bearing or a sliding bearing is generally used. When a bearing bush is used as the sliding bearing, the bearing is used. The bush is usually fixed in a hole in the steering shaft support.

When the bearing bush is fixed to the hole of the steering shaft support by press fitting, the dimensional error (tolerance) of the hole of the steering shaft support and the dimensional error of the thickness of the bearing bush are accumulated. However, after press-fitting, the inner diameter of the bearing bush varies greatly, and it may be difficult to fix the bearing bush to the hole with high inner diameter dimensional accuracy. It requires a precisely formed steering shaft support and bearing bush, which is extremely expensive.

Further, in the fixing by press-fitting the bearing bush into the hole of the steering shaft support, the outer diameter of the steering shaft support is affected by the swelling phenomenon of the outer surface of the steering shaft support based on the accumulation of the dimensional errors described above. For a steering shaft support that requires high dimensional accuracy even for its external shape, the fixing method by press fitting is not always optimal, and in order to deal with this, the thickness of the steering shaft support (wall thickness) In order to avoid the swelling phenomenon of the outer surface of the steering shaft support by using a thicker material or using a hard material to form the steering shaft support, the steering shaft support itself becomes large and becomes limited in a limited space. This may make it difficult to dispose, and may increase the price of the steering shaft support similarly to the above.

On the other hand, if the holes and the bearing bushes of the steering shaft support are formed with high precision in order to solve the above-mentioned disadvantages in the fixing method by press-fitting, it becomes expensive as described above, and conversely, it is not sufficient. It becomes difficult to fix the bearing bush in the hole of the steering shaft support with the fixing force, and in some cases, the bearing bush may rotate with the rotation of the steering input shaft during use, or may fall out of the hole of the steering shaft support. In particular, if the cylindrical inner wall surface that defines the hole of the steering shaft support is formed extremely smoothly in addition to high precision in order to facilitate press-fitting, the risk of rotation and falling off may be further increased. .

[0007] The above problem is that the other end of the steering column shaft, which is interposed between the steering wheel and the steering shaft support and whose one end is connected to the steering wheel, can be smoothly rotated via a bearing bush. This also occurs in the case of a steering shaft support that is supported in such a manner.

The present invention has been made in view of the above-mentioned points, and has as its object to reduce the dimensional error of the thickness of the bearing bush without being greatly affected by the dimensional error of the hole of the steering shaft support. Accordingly, it is an object of the present invention to provide a method capable of fixing the bearing bush to the hole of the steering shaft support with high internal diameter dimensional accuracy.

Another object of the present invention is to prevent the outer surface of the steering shaft support from bulging, so that the outer diameter of the steering shaft support is maintained even after the bearing bush is fixed. It is an object of the present invention to provide a method of fixing a bearing bush in a hole, which can be used and can use a thin steering shaft support.

It is a further object of the present invention to provide a steering shaft support having a hole and a bearing bush which are not accurately formed so as not to rotate and fall off during use. To provide a method in which the bearing bush can be firmly fixed to the hole and the inner wall surface defining the hole of the steering shaft support can be more firmly fixed to the hole of the steering shaft support by forming a rough cut. is there.

[0011]

According to a first aspect of the present invention, there is provided a method of fitting a bearing bush into a steering shaft support, comprising the steps of: A hole disposed adjacent to the bearing bush fitting hole in the axial direction,
An annular ring extending radially inward from the cylindrical inner wall surface to which the bearing bush is fitted and the cylindrical inner wall surface defining the hole and extending inward and terminating at the cylindrical inner wall surface between the cylindrical inner wall surface to which the bearing bush is fitted. Prepare a steering shaft support having an intervening surface, a cylindrical outer surface having a diameter that defines the inner diameter of the bearing bush after upsetting, and a cylindrical shape disposed axially adjacent to the cylindrical outer surface. An outer surface is provided, and a core bar is provided between the cylindrical outer surface and the cylindrical outer surface, the annular metal extending radially outward from the cylindrical outer surface and terminating at the cylindrical outer surface. And a part of the cylindrical outer surface of the cored bar is disposed in a hole of the steering shaft support, and the cylindrical outer surface of the cored bar is disposed in a bearing bush fitting hole of the steering shaft support, and the remaining portion of the cylindrical outer surface and Husband of steering shaft support and core metal And comprising a step of fixing the bearing bush in the cylindrical inner wall surface of the wearer fitted bearing bush with upset the bearing bush by the annular surface.

The method according to a second aspect of the present invention is characterized in that, in the above method, the cylindrical inner wall surface for fitting the bearing bush and the remaining portion of the cylindrical outer surface of the core metal, and the respective annular surfaces of the steering shaft support and the core metal. Until the volume of the annular space is close to the volume of the bearing bush.
An upset is performed with a gradual decrease, thereby fixing the bearing bush in the steering shaft support.

According to a third aspect of the present invention, in the above method, an upset pressure to be applied to the core metal when the volume of the annular space becomes close to the volume of the bearing bush is determined in advance, and the upset pressure is determined. The upset is completed by reaching.

In the methods of the second and third aspects, the term "near" includes a case where the volume of the annular space and the volume of the bearing bush are infinitely equal. Although the volume is about 99.9% or less of the volume of the annular space, the present invention is not limited to this, and the bearing bush is plastically flowed by the upset, and the bearing bush is substantially densely packed in the annular space. And the extent to which bulging of the outer surface of the steering shaft support does not occur or can be tolerated.

In the method of the present invention, the hole has a diameter substantially equal to or slightly larger than the inner diameter of the bearing bush after the upset as in the method of the fourth aspect of the present invention. Also, as in the method according to the fifth aspect of the present invention, the cylindrical inner wall surface on which the bearing bush is fitted and the cylindrical outer surface of the core metal are cylindrical surfaces, respectively, and the core metal cylinder is provided. The outer surface may have a diameter substantially equal to the diameter of the bearing bush fitting hole.

Further, in the method of the present invention, the inner wall surface of the cylinder defining the hole may be formed by the method of the sixth aspect of the present invention.
In the method according to the seventh aspect of the present invention, the inner peripheral surface of the annular body such as a washer mounted on the bearing bush fitting hole is formed by the steering shaft support itself.

The method according to an eighth aspect of the present invention comprises the step of mounting the bearing bush on the cylindrical surface of the metal core in advance in the method according to the present invention.
The method of the present invention includes a step of disposing the bearing bush in the bearing bush fitting hole in advance.

In the method according to the present invention, in the method according to the tenth aspect, the core metal is formed of a solid or a hollow body. In the present invention, a solid or hollow core can be used as described above. In particular, by using a hollow core, another member is arranged at the center of the bearing bush fitting hole of the steering shaft support. Even so, the bearing bush can be fixed to the steering shaft support without any problem.

In the method of the present invention, the upset bearing bush is a cylindrical bush, preferably a wound bush as in the method of the eleventh aspect of the present invention, and the wound bush is made of the present invention. As in the method of the eleventh aspect, at least three layers of a steel plate back metal, a porous metal sintered layer sintered on the back metal, and a synthetic resin layer filled and coated on the metal sintered layer More preferably, it has a structure.

The upset is performed by applying a load of about 1 to 10 tons, preferably about 2 to 7 tons. However, the present invention is not necessarily limited to this, and it depends on the material of the bearing bush and the steering shaft support. It may be determined appropriately.

In the present invention, the hole disposed adjacent to the bearing bush fitting hole in the axial direction may be a through hole or, alternatively, may be a bottomed hole. In the case of a hole, a bottomed hole or through hole may be further provided in the steering shaft support adjacent to the through hole in the axial direction.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention and its embodiments will be described in more detail with reference to the preferred examples shown in the drawings. The present invention is not limited to these embodiments.

In the method of this embodiment for fitting a bearing bush into a steering shaft support, first, as shown in FIG. 3, a bearing bush fitting hole 2 defined by a cylindrical inner wall surface 1 for fitting a bearing bush. And the bearing bush fitting hole 2 is disposed adjacent to the bearing bush fitting hole 2 in the axial direction and concentric with the bearing bush fitting hole 2, and has a diameter 3 of the bearing bush fitting hole 2.
Bearing bush 4 with smaller diameter than after upset
(See FIGS. 8 and 9), and has a hole 7 having a diameter 6 substantially equal to the inside diameter 5 of the inner surface of the cylinder that defines the cylindrical inner wall surface 1 of the bearing bush fitting hole 2 and the hole 7. A steering shaft support 11 having an annular surface 10 extending radially inward from the cylindrical inner wall surface 1 to which the bearing bush is fitted and terminating at the cylindrical inner wall surface 9 is interposed between the steering shaft support 11 and the wall surface 9. prepare.

The steering shaft support 11 has a cylindrical portion 12, a pinion gear portion 13 formed integrally with the cylindrical portion 12 and having teeth on its outer surface, and an attachment formed integrally with the pinion gear portion 13. The cylindrical portion 12 includes the bearing bush fitting hole 2, the bearing bush fitting hole 2, an axially upper portion adjacent to the bearing bush fitting hole 2, and concentric with the bearing bush fitting hole 2. And a hole 15 having a diameter larger than the diameter 3 of the bearing bush fitting hole 2 and an axially lower portion adjacent to the hole 7 and concentric with the bearing bush fitting hole 2. A hole 16 having a diameter smaller than the diameter 6 of the hole 7 is formed between the inner wall surface 9 of the cylinder and the inner wall surface 8 of the bottomed hole 16 in a radial direction from the inner wall surface 9 of the cylinder. And an annular surface 16a extending inward and terminating at the cylindrical inner wall surface 8 is interposed. Shoe fitting hole 2 and the hole 15 has a cylindrical shape, therefore, the wall surface 15a among which defines a cylindrical inner wall 1 and the holes 15 has a cylindrical surface, the pinion gear portion 1
Reference numeral 3 denotes a pinion gear of the rack and pinion gear mechanism.

The steering shaft support 11 (see FIGS. 8 and 9) in which the bearing bush 4 is fitted into the bearing bush fitting hole 2 by the method of this embodiment is, as shown in FIGS. Steering valve mechanism 17
Used for In the steering apparatus shown in FIGS. 1 and 2, a steering valve mechanism 17 that transmits the rotation of a steering wheel (not shown) to a rack and pinion gear mechanism generally has a hollow steering input shaft 18 and a hollow steering input shaft 18 for power steering. , A torsion bar 19 mounted in the steering input shaft 18, and the torsion bar 19 has a steering input shaft 18 at one end 19 a thereof.
The steering input shaft 18 is connected to the steering wheel at one end by a pin 20 and is fitted and fixed to the steering shaft support 11 at the other end 19b. In this embodiment, the bearing is rotatably supported by the steering shaft support 11 via the bearing bush 4. Other configurations for the rack and pinion gear mechanism and power steering are well known and need not be described in detail.

The bearing bush 4 fitted to the cylindrical inner wall surface 1 of the steering shaft support 11 is, as shown in FIGS. 4 to 6, a steel back metal 21 made of a steel plate and sintered on the steel back metal 21. A rectangular plate material 24 having a three-layer structure of a porous metal sintered layer 22 and a synthetic resin layer 23 filled and covered with the porous metal sintered layer 22 is wound into a cylindrical shape with the synthetic resin layer 23 inside. It is a formed winding bush. In carrying out the method of the present invention, it is needless to say that the present invention is not limited to such a wound bush, and may be, for example, a cylindrical bush.

In addition to preparing the steering shaft support 11, a metal core 31 as shown in FIG. 7 is prepared. Core 3
Reference numeral 1 denotes a cylindrical outer surface 33 having a diameter 32 that defines the inner diameter 5 of the bearing bush 4 after the upset, and is disposed adjacent to the cylindrical outer surface 33 axially upward and concentric with the cylindrical outer surface 33. A cylindrical outer surface 35 having a diameter 34 larger than the diameter of the cylindrical outer surface 33 and substantially equal to the diameter 3 of the bearing bush fitting hole 2; And a cylindrical outer surface having a diameter smaller than the diameter of the cylindrical outer surface and substantially equal to or slightly smaller than the diameter of the bottomed hole. I have.

In the metal core 31, an annular surface 39 extending radially outward from the cylindrical outer surface 33 and terminating at the cylindrical outer surface 35 is interposed between the cylindrical outer surface 33 and the cylindrical outer surface 35. In addition, between the cylindrical outer surface 33 and the cylindrical outer surface 36, the cylindrical outer surface 36 extends radially inward from the cylindrical outer surface 33 and extends inward.
An annular surface 40 terminating at the end is interposed.

The core metal 31 of this embodiment is a solid body formed by integrally forming a cylindrical portion 41, a cylindrical portion 42 having a larger diameter than the cylindrical portion 41, and a cylindrical portion 43 having a smaller diameter than the cylindrical portion 41. In the metal core 31, the cylindrical outer surface 33 is formed on the cylindrical portion 41,
A cylindrical outer surface 35 is formed on the cylindrical portion 42, and a cylindrical outer surface 36 is formed on the cylindrical portion 43, respectively.
Is a cylindrical surface. In the core metal 31 of this example, the end of the cylindrical portion 41 on the insertion side into the hole 7 and the hole 16 of the cylindrical portion 43 are formed.
An insertion guide surface 4 which is tapered
5 and 46 are respectively formed.

The above-described steering shaft support 11 and the core metal 31 are prepared. Next, as shown in FIG. 7, the mounting portion 14 of the steering shaft support 11 is inserted into the hole 52 of the positioning pressure pad 51 further prepared. The steering shaft support 11 is supported by being fitted, and the cylindrical portion 54 of the cylindrical guide jig 53 prepared separately is also fitted into the hole 15 of the steering shaft support 11. The cylindrical portion 54 of the guide jig 53 is formed such that its inner diameter is substantially equal to the diameter 3 of the bearing bush fitting hole 2. 55 is a knockout pin. In the present invention, such a guide jig 53 does not necessarily have to be provided.

Next, the cylindrical outer surface 3 of the cylindrical portion 41 of the cored bar 31 will be described.
7, the bearing bush 4 is mounted by using the insertion guide surface 45. Next, as shown in FIG.
And the core 31 is positioned with respect to the steering shaft support 11, and a load in the direction A is applied to the core 31 to position the core 31 with the positioning pressure pad 5.
Move toward 1.

Further, as shown in FIG. 8, a part of the cylindrical outer surface 33 of the metal core 31 is provided in the hole 7 of the steering shaft support 11, and the cylindrical external surface 35 of the metal core 31 is provided in the bearing bush of the steering shaft support 11. The cylindrical outer surface 36 of the core bar 31 is disposed in the fitting hole 2 in the hole 16 of the steering shaft support 11, respectively, and the remaining portion of the cylindrical outer surface 33 and the cylindrical portion 12 and the core bar 31 of the steering shaft support 11 are respectively provided. The bearing bush 4 is upset by the annular surfaces 10 and 39, and the bearing bush 4 is fixed to the cylindrical inner wall surface 1.

In this upset, the volume of the annular space 61 formed by the remaining portion of the cylindrical inner wall surface 1 and the cylindrical outer surface 33 and the annular surfaces 10 and 39 is reduced.
Is gradually reduced until the volume becomes close to the volume of the bearing bush 4.
An axial compressive force is applied to the bearing bush 4 to reduce the axial length of the bearing bush 4, and the bearing bush 4 is slightly plastically radially flowed based on the decrease in the axial length. Is pressed against the cylindrical inner wall surface 1.

The upset pressure to be applied to the core bar 31 when the volume of the annular space 61 becomes close to the volume of the bearing bush 4 is preferably obtained in advance, and the upset is completed when the upset pressure is reached. The upset is completed before the annular surface 40 comes into contact with the annular surface 16a.

According to the above-described method, the bearing bush 4 is upset by the cored bar 31 and fixed to the cylindrical inner wall surface 1. Therefore, the bearing bush 4 is not so affected by the dimensional error of the diameter 3 of the bearing bush fitting hole 2. In addition, a dimensional error in the thickness of the bearing bush 4 can be corrected, and the bearing bush 4 can be fixed to the cylindrical inner wall surface 1 in the bearing bush fitting hole 2 with a high inner diameter dimensional accuracy. Steering shaft support 11 with bearing bush 4 as shown in FIG.
Can be obtained.

According to the above method, the bearing bush 4
To reduce the axial length of the bearing bush 4 by applying a compressive force in the axial direction to the bearing bush 4, while only slightly plastically flowing the bearing bush 4 in the radial direction based on the decrease in the axial length. Therefore, the swelling phenomenon of the outer surface of the cylindrical portion 12 of the steering shaft support 11 does not occur. As a result, the outer diameter of the cylindrical portion 12 of the steering shaft support 11 can be maintained as it is after the fixing, and the thin cylinder can be maintained. The part 12 can be used.

Further, according to the above method, the bearing bush 4
May be slightly plastically flowed in the radial direction, thereby fixing the bearing bush 4 to the cylindrical inner wall surface 1 in the bearing bush fitting hole 2. Therefore, the cylindrical inner wall surface 1 may be formed by rough cutting.
Moreover, when the cylindrical inner wall surface 1 is formed by rough cutting, the bearing bush 4 can be more securely fixed to the cylindrical inner wall surface 1.

In the above example, the cylindrical portion 4 of the cored bar 31 is used.
1, the bearing bush 4 was previously mounted, but instead of this,
The bearing bush 4 may be mounted in the bearing bush fitting hole 2 in advance, and then the core metal 31 may be inserted into the guide jig 53.

In the above example, the hole 7 is formed in the steering shaft support 11 itself, and the hole 7 is defined by the inner peripheral surface 9 of the steering shaft support 11 itself. As shown in FIG. 10, an annular body 71 such as a washer, which is separate from the steering shaft support 11, is attached to the bearing bush fitting hole 2, and the hole 7 is defined by the inner peripheral surface 72 of the annular body 71. You may do so.

In the above example, a solid body is used as the core metal 31. Alternatively, the core metal 31 may be formed from a hollow body 81 as shown in FIG. The core metal 31 has a cylindrical outer surface 33 having a diameter 32 that defines the inner diameter 5 of the bearing bush 4 after the upset, and a cylindrical outer surface 33.
And has a diameter 34 that is larger than the diameter of the cylindrical outer surface 33 and substantially equal to the diameter 3 of the bearing bush fitting hole 2 while being disposed adjacent to and above the cylindrical outer surface 33 in the axial direction. The cylindrical outer surface 35 and the cylindrical outer surface 33 are disposed adjacent to the cylindrical outer surface 33 below in the axial direction and concentric with the cylindrical outer surface 33.
A cylindrical outer surface having a diameter smaller than the diameter of the cylindrical outer surface and substantially equal to or slightly smaller than the diameter of the bottomed hole;
5, an annular surface 39 extending radially outward from the cylindrical outer surface 33 and ending at the cylindrical outer surface 35 is interposed between the cylindrical outer surface 33 and the cylindrical outer surface 36. An annular surface 40 extending radially inward from the outer cylindrical surface 33 and terminating at the outer cylindrical surface 36 is interposed.

A core metal 31 shown in FIG. 11 is prepared, and the bearing bush 4 is fixed to the cylindrical inner wall surface 1 in the bearing bush fitting hole 2 of the steering shaft support 11 using the core metal 31 in the same manner as described above. May be used, such a core metal 31
By using the steering shaft support 11
The bearing bush 4 can be fixed to the cylindrical inner wall surface 1 without any hindrance even if some other part is fixed to the center of the inside or the center protrudes.

The above manufacturing method can be applied to a case where a bearing bush is fixed to a steering shaft support which supports a steering column shaft interposed between a steering wheel and a steering shaft support so as to be able to rotate freely. The same can be applied.

[0043]

According to the present invention, the dimensional error of the hole of the steering shaft support is not so affected, and
The dimensional error in the thickness of the bearing bush can be corrected, so that the bearing bush can be fixed to the cylindrical inner wall surface with high inner diameter dimensional accuracy, and the swelling phenomenon of the outer surface of the steering shaft support can be caused. As a result, the outer diameter of the steering shaft support can be maintained as it is even after fixing, and a thin steering shaft support can be used. In addition, the cylindrical inner wall surface for fitting the bearing bush and the bearing bush itself can be precisely formed. Even if not formed well, the bearing bush can be firmly fixed to the cylindrical inner wall surface of the steering shaft support so that it does not rotate and fall off during use, and the cylindrical inner wall surface for fitting the bearing bush is formed by rough cutting By doing so, the bearing bush can be more securely fixed to the cylindrical inner wall surface of the steering shaft support.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a steering valve mechanism of a steering device.

FIG. 2 is a sectional view taken along line II-II shown in FIG.

FIG. 3 is a cross-sectional view of an example of a steering shaft support suitable for use in the method of the present invention.

FIG. 4 is a perspective view of an example of a bearing bush suitable for use in the method of the present invention.

FIG. 5 is a sectional view of the bearing bush shown in FIG. 4;

FIG. 6 is a sectional view of a plate for forming the bearing bush shown in FIG. 4;

FIG. 7 is a cross-sectional view of an example of a mold suitable for use in the method of the present invention and an explanatory diagram of one step.

FIG. 8 is an explanatory diagram of the final step of the method of the present invention.

FIG. 9 is an explanatory view of a steering shaft support to which a bearing bush is fixed according to the method of the present invention.

FIG. 10 is a partial cross-sectional explanatory view of another example in which a hole is formed in the steering shaft support shown in FIG. 3;

FIG. 11 is a sectional view of another example of a mold suitable for use in the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical inner wall surface for bearing bush fitting 2 Bearing bush fitting hole 4 Bearing bush 7 hole 9 Cylindrical inner wall surface 10 Annular surface 11 Steering shaft support 31 Core metal 33 Cylindrical outer surface 35 Cylindrical outer surface 39 Annular surface

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuaki Tsuji 3-5-8 Minamisenba, Chuo-ku, Osaka-shi, Osaka Inside Koyo Seiko Co., Ltd. (72) Inventor Masami Yonezawa 3-5-minamisenba, Chuo-ku, Osaka-shi, Osaka No. 8 Inside Koyo Seiko Co., Ltd. (72) Inventor Masayuki Kohama 1-11-2, Noribori, Nishi-ku, Osaka-shi, Osaka Inside Oilless Industrial Co., Ltd. Osaka Branch (72) Hideki Numazawa 1-11, Tanibori, Nishi-ku, Osaka-shi, Osaka No. 2 OILES INDUSTRIES CO., LTD. Osaka Branch (72) Inventor Hideyuki HASHIMOTO 2-31-1, Dobashi, Toyota City, Aichi Prefecture OILES INDUSTRIES CO., LTD. Toyota Branch F-term (reference) 3D033 FD06 FD07 3J017 AA01 DB07

Claims (14)

[Claims] 1. A bearing bush fitting hole defined by a cylindrical inner wall surface to which a bearing bush is fitted, and a hole disposed in the axial direction adjacent to the bearing bush fitting hole, An annular ring extending radially inward from the cylindrical inner wall surface to which the bearing bush is fitted and the cylindrical inner wall surface defining the hole and extending inward and terminating at the cylindrical inner wall surface between the cylindrical inner wall surface to which the bearing bush is fitted. Prepare a steering shaft support having an intervening surface, a cylindrical outer surface having a diameter that defines the inner diameter of the bearing bush after upsetting, and a cylindrical shape disposed axially adjacent to the cylindrical outer surface. And an outer surface,
Between the cylindrical outer surface and the cylindrical outer surface, a step of preparing a metal core having an annular surface extending radially outward from the cylindrical outer surface and terminating at the cylindrical outer surface; and A part of the outer surface of the cylinder is disposed in a hole of the steering shaft support, and the cylindrical outer surface of the core is disposed in a bearing bush fitting hole of the steering shaft support. Fixing the bearing bush to the cylindrical inner wall surface on which the bearing bush is fitted by upsetting the bearing bush by the respective annular surfaces. 2. The volume of an annular space formed by a cylindrical inner wall surface fitted with a bearing bush, the remaining portion of the cylindrical outer surface of a metal core, and the respective annular surfaces of a steering shaft support and a metal core. The method according to claim 1, wherein the upset is performed by gradually decreasing the volume of the bearing bush until the volume becomes close to the volume of the bearing shaft. 3. An upset pressure to be applied to the core bar when the volume of the annular space is close to the volume of the bearing bush, and the upset is completed by reaching the upset pressure. A method for fixing a bearing bush in a steering shaft support according to claim 1. 4. The steering shaft according to claim 1, wherein the hole has a diameter substantially equal to or slightly larger than the inner diameter of the bearing bush after upsetting. A method of fixing a bearing bush in a support. 5. The cylindrical inner wall surface for fitting the bearing bush and the cylindrical outer surface of the core metal are respectively cylindrical surfaces, and the cylindrical outer surface of the core metal has a diameter substantially equal to the diameter of the bearing bush fitting hole. The method of fixing a bearing bush in a steering shaft support according to any one of claims 1 to 4, comprising: 6. The cylindrical inner wall surface defining the hole is formed by the steering shaft support itself.
A method of fixing a bearing bush in a steering shaft support according to any one of claims 1 to 5. 7. The steering shaft support body according to claim 1, wherein the cylindrical inner wall surface defining the hole is an inner peripheral surface of an annular body attached to the bearing bush fitting hole. How to fix the bush. 8. The method of fixing a bearing bush in a steering shaft support according to claim 1, further comprising the step of mounting the bearing bush on a cylindrical outer surface of a metal core in advance. 9. The method of fixing a bearing bush in a steering shaft support according to claim 1, further comprising a step of previously disposing the bearing bush in the bearing bush fitting hole. 10. The method for fixing a bearing bush in a steering shaft support according to any one of claims 1 to 9, wherein the core metal is formed of a solid body or a hollow body. 11. The method for fixing a bearing bush in a steering shaft support according to claim 1, wherein the bearing bush is a wound bush. 12. The bearing bush has at least a three-layer structure of a steel plate back metal, a porous metal sintered layer sintered on the back metal, and a synthetic resin layer filled and coated on the metal sintered layer. The method of fixing a bearing bush in a steering shaft support according to any one of claims 1 to 11, wherein the bush is a bush. 13. A bearing bush for use in the method according to any one of claims 1 to 12. 14. A steering shaft support for use in a method according to any one of the preceding claims.