JPH0592536U - Rolling bearing device - Google Patents

Abstract

(57) [Abstract] [Purpose] An oil film is stably formed on the entire outer peripheral surface of the outer ring, which is the cam surface, to prevent minute seizure and wear. An outer ring 4 provided in a rolling bearing device 1 attached to an eccentric rotary shaft 17 is manufactured by press molding, and an outer peripheral surface 4a of the outer ring 4 is made into an unpolished rough surface. As a result, a plurality of minute recesses 21 are formed on the outer peripheral surface 4a of the outer ring 4 and the outermost surface is made smooth. Therefore,
The lubricant is easily retained in the minute recesses 21, and
The lubricant here is transferred to the sliding contact surfaces of the plunger 11 and the outer ring 4 along with the sliding contact operation to form an oil film.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rolling bearing device used for a pumping mechanism included in an anti-skid device for an automobile, for example.

[0002]

[Prior Art]

 The anti-skid device for automobiles eliminates brake lock and prevents slips by pumping the hydraulic pressure applied to the wheel cylinders during sudden braking or braking on slippery roads. A pumping mechanism for doing

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

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

On the other hand, in the conventional example of FIG. 5, a general rolling bearing 18 having no inner ring is attached to an eccentric rotation shaft 17 formed integrally with the drive shaft 14 of the motor 10. In this case, the entire rolling bearing 18 is eccentrically rotated by the eccentric rotation of the eccentric rotation shaft 17, and the outer ring 18a of the eccentric rotation shaft 17 serves as a cam surface which is in sliding contact with the plunger 11 at one location of the eccentric rotation track. It

[0006]

[Problems to be solved by the device]

 By the way, each of the eccentric rolling bearings 16 and 18 used in the pumping mechanism has a relatively thick outer ring 16a and 18a manufactured by cutting, and these outer rings 16a and 18a The outer peripheral surface is polished.

When the outer peripheral surfaces of the outer rings 16a and 18a are observed microscopically, as shown in FIG. 6, there are innumerable fine streaks 20 ... By polishing in the circumferential direction. Therefore, on the outer peripheral surfaces of the outer rings 16a and 18a, the lubricant is axially divided by the polishing streak 20, and an oil film is hard to be formed, and a slight seizure is likely to occur at the contact portion with the plunger 11, and wear is likely to occur. ..

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

[0009]

[Means for Solving the Problems]

 According to the present invention, an eccentric rotation shaft, a plurality of rolling elements arranged on the outer periphery of the eccentric rotation shaft, an outer ring having a raceway portion of the rolling element formed on the inner peripheral surface and a cylindrical cam surface formed on the outer peripheral surface. And a cylindrical cam surface of the outer ring having a plurality of minute recesses and an outermost surface being a smooth surface.

[0010]

[Action]

 When the lubricant is held in the plurality of minute recesses, the lubricant held therein is transferred to the sliding contact surfaces of the outer ring and the sliding contact partner to form an oil film. In addition, since the plurality of minute recesses are separate from each other and have no directivity, the lubricant easily spreads over the entire outer peripheral surface of the outer ring. Moreover, since the outermost surface of the outer peripheral surface of the outer ring is smooth, abrasion is unlikely to occur during the sliding contact operation.

[0011]

【Example】

 Hereinafter, details of the present invention will be described based on an embodiment shown in FIGS. FIG. 1 shows a sectional view of a rolling bearing device. The rolling bearing device 1 is attached to an eccentric rotary shaft 17 which is integrally formed with a drive shaft 14 of a motor 10 as in the conventional example of FIG. is there. The rolling bearing device 1 has a shell-type bearing structure including a plurality of needle rollers 2, a cage 3 that rotatably holds the needle roller 2, and an outer ring 4 that surrounds the cage 3. Is becoming The plurality of needle rollers 2 and the cage 3 correspond to rolling elements described in the claims.

A cylindrical cam surface for the plunger 11 is formed on the outer peripheral surface 4a of the outer ring 4, and a plurality of minute recesses 21 are formed on the outer peripheral surface 4a as shown in FIG. In addition, the outermost surface is smooth. In order to obtain such an outer peripheral surface 4a, it is desirable to manufacture the outer ring 4 by pressing. Inner collars 4b and 4c are formed at both axial ends of the outer ring 4, and each of the inner free ends of the inner collars 4b and 4c is brought close to the eccentric rotary shaft 17, and the adjacent portions are labyrinth. It is said to be the seal part. The outer ring 4 is filled with a lubricant such as grease.

A procedure for manufacturing such a rolling bearing device 1 will be described with reference to the process chart of FIG. First, 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. 3A is prepared. As the circular substrate A1, a bright material (polishing material) having a surface finish roughness of 0.4 to 3S (JIS standard B0601) is used. By subjecting this circular substrate A1 to press drawing, it is formed into a cup shape with one end open and the other end closed, as shown in FIG. 3 (b). At the time of this drawing, it is desirable that the vicinity of the opening end (the portion that becomes the inner collar 4c) of the cup-shaped member A2 be thinner than the other portions. After that, a small-diameter through hole is formed in the bottom of the cup-shaped member A2 so as to leave the inner collar 4b, and then the whole is quenched to increase the strength, and the opening end of the cup-shaped member A2 ( The part that will become the inner collar 4c) is tempered. The cage 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. By forming the inner collar 4c by bending inward in the radial direction, the outer ring 4 is completed, as shown in FIG. 3 will be prevented from falling off.

The outer peripheral surface 4a of the outer ring 4 thus manufactured by press drawing is left un-polished while remaining rough as pressed. Therefore, fine irregularities (see FIG. 2) of the rough surface during press molding remain on the surface of the outer peripheral surface 4a of the outer ring 4 (the roughness is approximately Rz2 to 3 at the roughest location), but Since there is no directivity and the convex and concave portions are not continuous in a long line in the circumferential direction, the lubricant easily spreads on the outer peripheral surface 4a of the outer ring 4 and the outer peripheral surface 4a of the outer ring 4 as a whole. An oil film will be formed on the surface. Moreover, the tips of the respective convex portions of the concavities and convexities are flattened and do not become sharp due to pressure contact with the press die, so that good lubrication is performed with the plunger 11. On the other hand, since the raceway surface of the inner peripheral surface of the outer ring 4 is on the side of the punch die which is the counterpart member for press drawing, the outer peripheral surface 4a is slightly rougher.

Further, in the eccentric rolling bearing device 1 of the present invention, the axial end portion of the outer ring 4 is slidably contacted with the step portion 19 between the drive shaft 14 and the eccentric rotary shaft 17 by swinging in the axial direction. However, since the inner flanges 4b and 4c at the axial end of the outer ring 4 are made wider in the radial direction, the contact surface pressure with the step 19 is produced by conventional cutting. It becomes lower, and wear at the axial end portion of the outer ring 4 is reduced.

In addition, since the needle roller 2 and the cage 3 are surrounded by the outer ring 4, the outer ring 4 suppresses the scattering of the lubricant inside, and the eccentric rotation shaft 17 and The lubricity between them is also maintained well.

The present invention is not limited to the above embodiment. For example, the cage 3 may not be used, and the plurality of needle rollers 2 alone can constitute the rolling element according to the claims. Further, the eccentric rotation shaft 17 of the above-described embodiment is, as shown in the conventional example of FIG. 4, an inner ring having a shaft hole formed at an eccentric position and a motor drive shaft concentric with an outer ring of which the inner ring is mounted. It may be configured with a mounting shaft.

Further, when the rolling bearing device 1 of the embodiment of the present invention is used in the hydraulic unit of the anti-skid device of the automobile as described in the conventional example, the eccentric rotary shaft 17 and the drive shaft 14 are It serves as the output shaft of the electric motor of the pumping mechanism in the hydraulic unit, and the plunger 11 serves as the plunger of the pumping mechanism. Of course, the rolling bearing device of the present invention can be applied to various things other than the hydraulic unit of the antiskid device of the automobile.

[0019]

[Effect of the device]

 As described above, according to the present invention, the oil film can be stably formed on the entire outer peripheral surface of the outer ring, which is the cam surface that makes sliding contact with the plunger. It becomes possible to prevent seizure and wear.

[Brief description of drawings]

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

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

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

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

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rolling bearing device 2 Needle rollers 4 Outer ring 4a Outer ring outer peripheral surface 17 Eccentric rotation shaft 21 Minute recess

Claims (1)

[Scope of utility model registration request] 1. An outer ring having an eccentric rotation shaft, a plurality of rolling elements arranged on the outer circumference of the eccentric rotation shaft, a raceway portion of the rolling element formed on the inner peripheral surface, and a cylindrical cam surface formed on the outer peripheral surface. And a cylindrical cam surface of the outer ring having a plurality of minute recesses and an outermost surface being a smooth surface.