JPH0586025U - Bearing for steering column - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a bearing for a steering column, which can suppress the occurrence of vibration when the bearing is used, and can improve the roundness of the bearing ring and the work efficiency in the production thereof. [Constitution] A bearing ring (1) that contacts the roller (2) on the inner diameter surface
A V-shaped crack (6) is formed at one location on the circumferential surface of the. The crevice (6) is formed symmetrically with respect to the axial centerline (XX), and the bent portion (7) is formed in the circumferential direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bearing for a steering column attached to a steering device of an automobile or the like.

[0002]

[Prior Art]

 As a bearing for supporting a steering shaft of an automobile or the like in a steering column, a steering column bearing shown in FIGS. 1 (a) and 1 (b) has been conventionally used. This bearing has a thin-walled cylindrical race ring (1), a large number of needle rollers (2) incorporated inside the race ring (1) [hereinafter simply referred to as "rollers"] and a cage ( 3), an elastic outer cylinder (4) enclosing the bearing ring (1).

Of the above-mentioned components, the elastic outer cylinder (4) is formed of an elastic body such as rubber, and therefore has an annular shape extending in the axial direction in order to prevent grease leakage and foreign matter intrusion. The seal part (8) is integrally provided. The bearing ring (1) is manufactured by bending a steel plate into a cylindrical shape and then subjecting it to heat treatment, and as shown in FIGS. A substantially S-shaped crack (6) is formed.

The steering column bearing having the above configuration is press-fitted and mounted in the steering column. At the time of this press-fitting, the elastic outer cylinder (4) is compressed in the radial direction, and the race ring (1) is also compressed while closing the cracks (6), so that a proper preload is applied to the bearing.

[0005]

[Problems to be solved by the device]

 By the way, in the bearing ring shown in FIGS. 3 and 4, the crack (6) is formed asymmetrically with respect to the axial center line (X'-X '), and therefore, when the bearing ring (1) is manufactured. Residual stress generated by bending process is distributed unevenly at both ends (1a) (1b) of the bearing ring (1). Therefore, both ends (1a) and (1b) are unevenly expanded by the heat treatment after bending, which may deform the bearing ring (1) and reduce the roundness. Such a decrease in roundness leads to a decrease in various performances of the bearing, and therefore improvement has been demanded.

Further, in the conventional bearing ring, the circumferential length (s) of the crack is relatively long. This crack is closed by press-fitting the bearing into the steering column as described above, but at this time, as shown in FIG. 5, strictly speaking, if there is a minute step at the crack (6). Conceivable. Therefore, when the circumferential length (s) of the crack (6) is long, it takes a long time for the roller (2) to pass through the step, and there is a problem that vibration due to rolling of the roller increases. there were.

Further, in the conventional bearing ring, as shown in FIG. 3B, the crack (6) expands when an axial tensile load is applied. If the crack (6) expands in this manner, another race may enter the crack (6) and the races may be entangled with each other. Therefore, when a large number of bearing rings were stored during the manufacturing process of the bearing, the entanglement prevented the bearing rings from being taken out smoothly, resulting in a decrease in the efficiency of assembly work.

In view of these problems, the present invention can suppress the occurrence of vibration when using a bearing, and can improve the roundness of the bearing ring and the work efficiency at the time of manufacturing the steering column. The object is to provide a bearing for use.

[0009]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a cylindrical raceway ring with a split that divides a circumferential surface, a plurality of rollers installed inside the raceway ring, and a roller. In a device provided with a retainer that holds the bearing ring in a predetermined position and an elastic outer cylinder that wraps the bearing ring, a crack in the bearing ring is formed with a bent portion and symmetrically with respect to an axial centerline. ing.

[0010]

[Action]

 By forming cracks symmetrical with respect to the axial centerline of the bearing ring, residual stress due to bending of the bearing ring is generated evenly on the left and right of the axial centerline. As a result, thermal expansion during heat treatment occurs evenly on the left and right of the axial centerline, so that deformation of the bearing ring can be suppressed and high roundness can be maintained. Further, since the circumferential length of the crack is shorter than that of the conventional product, the time required for the roller to pass through the step can be shortened. This makes it possible to suppress the occurrence of vibration when the bearing is used. Further, by providing the bent portion in the crack, both ends of the bearing ring are engaged with each other to prevent the crack from expanding when an axial tensile or compressive load is applied. Therefore, it becomes possible to prevent entanglement between the bearing rings.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

As shown in FIGS. 1 (a) and 1 (b), the steering column bearing of the present invention has a thin-walled cylindrical race ring (1), a large number of rollers (2), and a cage as in the conventional products. (3) The elastic outer cylinder (4) is integrally provided with the seal portion (8).

In the present invention, as shown in FIGS. 1 (c) and 2 (a), a V-shaped crack (6) is formed in the bearing ring (1). The split (6) is symmetrical with respect to the axial centerline (XX) and is bent in the circumferential direction at the V-shaped portion. Here, the "axial center line" means a line passing through the middle of the axial length (t) of the bearing ring (1).

By forming the cracks (6) symmetrical with respect to the axial centerline (XX) in this way, the residual stress generated by the bending process at the time of manufacturing the bearing ring (1) is reduced. It is evenly distributed on the left and right of the directional center line (XX). As a result, during heat treatment after bending, the race ring (1) expands evenly on the left and right sides of the axial center line (XX), so that its circularity is less likely to change. Also, compared with the conventional bearing ring (1) shown in Fig. 3, even when the angle of inclination of the split (6) is the same, the circumferential length (s) is about half that of the conventional product. ing. From this, the time required for the roller (2) to pass through the step is also reduced to about half, and it is possible to suppress the occurrence of vibration due to the rolling of the roller (2). Further, since the crack (6) has a bent portion (7) in the circumferential direction, both ends (1a) (1b) of the bearing ring (1) are engaged by axial tensile and compressive loads. As a result, the cracks (6) can be prevented from expanding, and when a large number of bearing rings (1) are stored, the bearing rings (1) do not become entangled with each other.

The shape of the crack (6) is not limited to the V-shape, but a shape having a bent portion (7) in the circumferential direction, for example, a substantially U-shape as shown in FIGS. 2 (b) and (c). The same action and effect as described above can be achieved by using a mold or a convex mold.

[0016]

[Effect of the device]

 As described above, according to the present invention, the high roundness of the bearing ring can be maintained even after the heat treatment, and the vibration generated when the bearing is used can be suppressed, so that various performances of the bearing can be improved. On the other hand, since it is possible to prevent the circularity of the bearing ring from decreasing as described above, it is possible to reduce the defect rate during the manufacture of the bearing ring. Further, even if a large number of bearing rings are stored during the process of assembling the bearing, the bearing rings do not become entangled with each other, so that the assembly work can be performed smoothly. Therefore, productivity at the time of bearing assembly can be improved.

[Brief description of drawings]

1A and 1B are views showing an embodiment of a steering column bearing according to the present invention, in which FIG. 1A is a partial cross-sectional side view, FIG. 1B is a front view, and FIG. It is a perspective view of a bearing ring.

FIG. 2 is a side view showing an example of a shape of a crack formed on a bearing ring.

FIG. 3 is a perspective view (a) and a side view (b) of a conventional bearing ring.
Is.

FIG. 4 is a side view showing another example of a conventional crack.

FIG. 5 is a cross-sectional view showing a state of a crack at the time of press fitting into a steering column.

[Explanation of symbols]

 1 orbital ring 2 roller 3 cage 4 elastic outer cylinder 6 crack XX axis center line

Claims (1)

[Scope of utility model registration request] 1. A cylindrical bearing ring having a split formed at one location on the circumferential surface, a plurality of rollers incorporated inside the bearing ring, and a retainer for holding the rollers at a predetermined position. And a resilient outer cylinder that encloses the bearing ring, wherein a crack in the bearing ring has a bent portion and is formed symmetrically with respect to an axial centerline. Bearings.