JP2589044Y2 - Rolling bearing device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing device used for a pumping mechanism included in, for example, an anti-skid device of an automobile.

[0002]

2. Description of the Related Art An anti-skid device of an automobile is designed to eliminate brake lock and prevent slippage by pumping hydraulic pressure applied to a wheel cylinder when braking suddenly or when braking on a slippery road surface. And a pumping mechanism for performing hydraulic pumping.

FIGS. 4 and 5 show a conventional pumping mechanism.
As shown in (1), the rotation of the motor 10 is converted into the reciprocating motion of the plunger 11 to perform a pumping action. The plunger 11 is slidably fitted in a cylinder 13 provided in a housing 12.

In the conventional pumping mechanism shown in FIG. 4, an eccentric rolling bearing 16 serving as a cam is mounted on a mounting shaft 15 formed concentrically with a drive shaft 14 of a motor 10, and an outer ring of the bearing 16 is provided. The outer peripheral surface of 16a slides on the plunger 11 as a cam surface. The eccentric rolling bearing 16 has an inner ring 16b.
A shaft hole is formed in b at an eccentric position (see Japanese Utility Model Laid-Open No. 2-146220).

On the other hand, in the conventional example shown in FIG. 5, a general rolling bearing 18 without an inner ring is attached to an eccentric rotating shaft 17 formed integrally with a driving shaft 14 of a motor 10. In this case, the rolling bearing 18 as a whole is eccentrically rotated by the eccentric rotation of the eccentric rotation shaft 17, and the outer ring 18a is moved at one place of the eccentric rotation track.
The cam surface is in sliding contact with the cam surface.

[0006]

The eccentric rolling bearings 16 and 18 used for the pumping mechanism are:
Each of them has a relatively thick outer ring 16a, 18a manufactured by cutting, and the outer ring 16a, 18a
The outer peripheral surface of 18a is polished.

When the outer peripheral surfaces of the outer rings 16a and 18a are observed microscopically, as shown in FIG. 6, there are countless fine streaks 20... For this reason, on the outer peripheral surfaces of the outer rings 16a and 18a, the lubricant is divided in the axial direction by the polishing streaks 20, so that an oil film is not easily formed.

The present invention addresses the above-mentioned conventional problems. An oil film is stably formed on the entire outer peripheral surface of an outer ring serving as a cam surface so that minute seizure and wear can be prevented. The task is to

[0009]

According to the present invention, there is provided an eccentric rotary shaft, a plurality of rolling elements arranged on the outer circumference of the eccentric rotary shaft, and a track portion of the rolling element formed on an inner circumferential surface, and a cylindrical shape formed on an outer circumferential surface. In a rolling bearing device provided with an outer ring having a cam-shaped surface, the cylindrical cam surface of the outer ring has a plurality of minute concave portions and the outermost surface is a smooth surface.

[0010]

When the lubricant is retained in the plurality of minute recesses, the lubricant retained therein is transferred to the sliding surfaces of the outer ring and the sliding contact with the sliding contact of the outer ring, and the oil film is formed. Becomes
Since the plurality of minute recesses are separate and have no directionality, the lubricant easily spreads over the entire outer peripheral surface of the outer ring. Further, since the outermost surface of the outer peripheral surface of the outer ring is smooth, abrasion hardly occurs during the sliding operation.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to one embodiment shown in FIGS. FIG. 1 is a sectional view of a rolling bearing device. The rolling bearing device 1 is mounted on an eccentric rotary shaft 17 formed integrally with a drive shaft 14 of a motor 10 as in the conventional example of FIG. The rolling bearing device 1 includes a plurality of needle rollers 2 and needle rollers 2.
Are rotatably held, and a shell-type bearing structure including an outer ring 4 surrounding the retainers 3.
The plurality of needle rollers 2 and the retainer 3 correspond to a rolling element described in the claims.

A cylindrical cam surface for the plunger 11 is formed on the outer peripheral surface 4a of the outer race 4.
As shown in FIG. 2, a plurality of minute concave portions 21 are formed on a, and the outermost surface is a smooth surface.
In order to obtain such an outer peripheral surface 4a, it is desirable to manufacture the outer race 4 by press working. Inner flanges 4b, 4c are formed at both axial ends of the outer ring 4, and the inner collars 4b, 4c
Each of the inner free ends is brought close to the eccentric rotary shaft 17, and the close part is a labyrinth seal portion. The inside of the outer ring 4 is filled with a lubricant such as grease.

The manufacturing procedure of such a rolling bearing device 1 will be described with reference to the process chart of FIG. First, FIG.
A circular substrate A1 made of a thick alloy steel plate such as carbon steel or SCM material (chrome molybdenum steel) as shown in FIG. This circular substrate A1 has a surface finish roughness of 0.
A bright material (polishing material) of 4 to 3S (JIS B0601) is used. By subjecting the circular substrate A1 to press drawing, it is formed into a cup shape in which one end is open and the other end is closed, as shown in FIG. At the time of this drawing, it is desirable to make the vicinity of the opening end (the part to be the inner flange 4c) of the cup-shaped member A2 thinner than other parts. Thereafter, a small-diameter through-hole is formed at the bottom of the cup-shaped member A2 so as to leave the inner flange 4b, and then the entire body is quenched to increase the strength. The temper is applied to the part to be the flange 4c. A retainer 3 holding the needle rollers 2 is inserted inward from the open end side of the cup-shaped member A2 in the direction of the arrow in FIG. 3C, and in this state, inserted into the open end of the cup-shaped member A2. By forming the inner flange 4c by bending inward in the radial direction, the outer ring 4 is completed as shown in FIG. 3D, and the retainer 3 from the outer ring 4 is Prevents falling off.

The outer peripheral surface 4a of the outer ring 4 manufactured by the press drawing is not polished while the rough surface of the press drawing remains as it is. For this reason, the surface of the outer peripheral surface 4a of the outer race 4 has fine irregularities on the rough surface during press molding (see FIG. 2).
Remain (the roughness is approximately Rz2 to 3 at the roughest point), but the unevenness has no directionality, and the convexities of the unevenness do not continue in a streak-like manner in the circumferential direction. The lubricant is easy to spread on the outer peripheral surface 4a of 4,
An oil film is formed on the entire outer peripheral surface 4a of the outer race 4.
In addition, since the tips of the projections of the projections and depressions are flattened and do not become sharp due to the pressure contact with the press die, good lubrication with the plunger 11 is performed. On the other hand, since the raceway surface of the inner peripheral surface of the outer ring 4 is on the side of the punching die which is a partner of the press drawing, the roughness is slightly coarser than the outer peripheral surface 4a.

Further, in the eccentric rolling bearing device 1 of the present invention, the axial end of the outer race 4 slides on the step 19 between the drive shaft 14 and the eccentric rotary shaft 17 by oscillating in the axial direction. However, since the radial width of the inner flanges 4b and 4c at the axial end of the outer ring 4 is increased, the contact surface pressure with the step 19 is lower than that of the outer ring manufactured by conventional cutting. Therefore, wear at the axial end of the outer race 4 is reduced.

In addition, since the needle roller 2 and the retainer 3 are surrounded by the outer ring 4, the outer ring 4 suppresses the scattering of the internal lubricant, and the like. Good lubricity is also maintained.

The present invention is not limited to the above embodiment. For example, the retainer 3 may not be used, and the rolling element described in the claims can be constituted only by the plurality of needle rollers 2. Further, as shown in the conventional example of FIG. 4, the eccentric rotary shaft 17 of the above embodiment has an inner ring having a shaft hole formed at an eccentric position, and a mounting concentric with a motor drive shaft to which the inner ring is externally mounted. It may be constituted by a shaft.

Further, when the rolling bearing device 1 according to the embodiment of the present invention is used for a hydraulic unit of an anti-skid device of an automobile as described in the conventional example, the eccentric rotating shaft 1
The drive shaft 7 and the drive shaft 14 serve as output shafts of an electric motor of a pumping mechanism in the hydraulic unit, and the plunger 11 serves as a plunger of the pumping mechanism. Of course, the rolling bearing device of the present invention can be applied to various types other than the hydraulic unit of the anti-skid device of the automobile.

[0019]

As described above, according to the present invention, an oil film can be stably formed on the entire outer peripheral surface of the outer ring, which is the cam surface that comes into sliding contact with the plunger, so that sliding with the plunger can be achieved. Fine seizure and abrasion due to contact can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the rolling bearing device of the present invention.

FIG. 2 is a perspective view showing the outer peripheral surface of the outer ring of the device of the present invention.

FIG. 3 is a process chart showing a manufacturing procedure of the device of the present invention.

FIG. 4 is a sectional view of a pumping mechanism provided with a conventional rolling bearing.

FIG. 5 is a cross-sectional view of a pumping mechanism provided with another conventional rolling bearing.

FIG. 6 is a perspective view showing the outer peripheral surface of the outer ring of the conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling bearing device 2 Needle roller 4 Outer ring 4a Outer surface of outer ring 17 Eccentric rotation shaft 21 Micro concave

Claims (1)

(57) [Scope of request for utility model registration] 1. An eccentric rotary shaft, a plurality of rolling elements disposed on the outer circumference of the eccentric rotary shaft, and an outer ring having a track portion of the rolling element formed on an inner circumferential surface and a cylindrical cam surface formed on an outer circumferential surface. A rolling bearing device comprising: a cylindrical cam surface of the outer ring having a plurality of minute recesses and an outermost surface being a smooth surface.