JPH0814251A - Holder for thrust roller bearing - Google Patents

Abstract

PURPOSE:To suppress the progress of the wear between a holder and the rotation guide surface of a guide member without adding a surface treatment or press process in a holder for thrust roller bearing formed by press-working a steel plate. CONSTITUTION:Bent turned parts 4, 5, 6 are provided on the bore side, outer diameter side and central part of the end surface 3 of a ring steel plate 2, the bore-side turned part 4a forming a rotation guide surface is extended in the thickness direction of the steel plate 2 to the end surface of the steel plate 2. Since the area of the guide surface is thus extended by the extended portion to reduce the surface pressure acting on the guide surface, the progress of the wear between a shaft 12 and the guide surface of a holder 1 is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cage made of a pressed steel plate used for thrust roller bearings.

[0002]

2. Description of the Related Art As a cage for thrust roller bearings, a cage formed by press forming a thin steel plate is known as a cage having excellent heat resistance, a reduced material cost and a reduced weight.

As shown in FIGS. 1 and 6, this cage made of pressed steel plate has an inner diameter side end portion and an outer diameter side end portion at an end surface 3 of an annular steel plate 2 in order to secure the strength of the cage. And the center portion between the inner and outer diameter ends is bent by pressing in the same direction in the thickness direction of the steel sheet and then folded back, and the three bent folding portions 4, 5 and 6 form a cross section in the circumferential direction of the steel sheet 2. It is transformed into a substantially W shape.

Further, a plurality of pockets 7 are formed on the end surface of the steel plate 2 at regular intervals in the circumferential direction, and the peripheral surface of the cylindrical roller 10 housed in each pocket 7 is bent and folded at the central portion.
It is held by the pocket side surfaces 8 and 9 on both sides.

As shown in FIG. 5, the cage 1 made of pressed steel plate has a housing 1 with a cylindrical roller 10 housed in each pocket 7 held between an inner ring 13 and an outer ring 14.
The thrust roller bearing is configured by being assembled between the shaft 1 and the shaft 12, and the folded portion 4a on the inner diameter side and the shaft 1 are arranged.
2, or the folded portion 5a on the outer diameter side and the housing 11 are in sliding contact with each other to guide the rotation.

The inner-diameter side or outer-diameter side folded-back portions 4a and 5a, which serve as guide surfaces for rotation, are folded back in close contact with the bent portions 4b and 5b in order to increase the deformation resistance of the edges of the steel sheet. The front end portion is formed to be substantially flush with the flat end surface 3 of the steel plate 2 together with the bent and folded portion 6 in the central portion.

[0007]

By the way, in the cage 1 of the inner diameter guide type or the outer diameter guide type as described above, the folded-back portions 4a, 5a serving as guide surfaces are provided under the condition that the rotation speed of the bearing is high.
The surface pressure between the housing and the surface of the housing 11 or the shaft 12 becomes large, which may cause wear of the guide surface.

In particular, under severe lubrication conditions or under conditions where a radial component force is generated, there is a problem that the surface pressure of the guide surface becomes extremely large and the progress of wear is accelerated.

As a method of dealing with such a problem, there is a method of increasing the surface hardness of the folded portions 4a, 5a of the cage 1 to suppress the progress of wear. In this method, the surface of the housing 11 or the shaft 12 is The hardness also needs to be increased, which has the drawback of increasing the manufacturing process of the bearing and increasing the cost.

Therefore, the present invention solves the above problems and suppresses the progress of wear of the guide surface of the cage and the surface of the guide member with which the guide surface contacts without increasing the manufacturing process and increasing the cost. It is an object of the present invention to provide a cage for a thrust roller bearing that can be manufactured.

[0011]

In order to solve the above-mentioned problems, the present invention relates to an inner surface of an annular steel plate, an inner diameter side end portion, an outer diameter side end portion, and a center portion between the inner and outer diameter end portions, respectively. After bending back in the same direction in the thickness direction, a plurality of pockets are formed on the end surface of the steel plate at predetermined intervals in the circumferential direction, and the rollers housed in the pockets are bent at the center and at both sides. A rotation guide surface that is held by the side surface of the pocket, and one or both of the folded portions on the inner diameter side and the outer diameter side are extended in the thickness direction of the steel sheet with respect to the end surface of the steel sheet, and the extended folded portions contact other members. It was.

[0012]

In the above construction, the area of the guide surface is expanded by extending the folded portion on the inner diameter side or the outer diameter side, which becomes the guide surface, and the surface that acts on the unit area of the guide surface by the expanded amount. The pressure can be reduced. Therefore,
The progress of wear on the guide surface is suppressed, and the durability of the cage and the guide member with which the cage contacts can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. This cage 1 is of an inner diameter guide type, and in the end surface 3 of an annular steel plate 2, bent and folded portions 4, 5 and 6 are formed on the inner diameter side, the outer diameter side and the central portion, respectively. A plurality of pockets 7 are formed with a size that crosses the bent and folded portion 6 in the radial direction. Further, the tip of the folded-back portion 4a on the inner diameter side is extended in the thickness direction of the steel sheet with respect to the flat end surface 3 of the steel sheet 2, and the extended folded-back portion 4 is formed.
The entire surface of a is used as a rotation guide surface that makes sliding contact with the shaft 12.

In the structure described above, the area of the folded-back portion 4a on the inner diameter side is expanded by the amount of extension compared with the conventional product shown in FIG. 6, and when the folded-back portion 4a and the shaft 12 come into contact with each other, the contact surface The surface pressure acting per unit area becomes small. Therefore, even under a condition of high rotational speed or a condition in which a radial component force is exerted, sliding contact between the folded-back portion 4a and the shaft 12 is made smooth, and wear generated on the contact surface can be suppressed. The durability of the guide surface of the cage can be improved.

As described above, the processing for extending only the tip of the folded-back portion 4a can be dealt with by slightly modifying the shape of the press die, and the addition of new surface treatment and the work process of the press processing are increased. Since it is not necessary, it can be manufactured at almost the same manufacturing cost as the conventional product.

In contrast to the above, FIG. 3 shows an embodiment applied to a cage of an outer diameter guide type. In this case, the tip of the folded portion 5a on the outer diameter side which makes sliding contact with the housing 11 is provided. The end face 3 is extended in the thickness direction of the steel plate 2.

Other structures and operations are the same as those in the above-mentioned embodiment, and the same parts are designated by the same reference numerals and the description thereof will be omitted.

On the other hand, in the cage shown in FIG. 4, both the inner diameter side and the outer diameter side folded-back portions 4a, 5a are extended in the thickness direction with respect to the end surface of the steel plate 2, and the inner diameter guide method and the outer diameter are adopted. It can be used for both directions.

In each of the above-described embodiments, the width for extending the folded-back portions 4a, 5a is set to a width that is more than the width that can effectively reduce the surface pressure of the guide surface, and is set within a width that is allowable in the internal design of the bearing. To do so.

[0020]

As described above, according to the present invention, the folded portion on the inner and outer diameter sides of the retainer is extended to reduce the surface pressure acting on the guide surface, so that the guide surface slides smoothly and wear is prevented. It is possible to suppress the generation, and it is possible to greatly improve the durable life of the cage and the guide member that comes into contact with the cage.

Further, the extension of the folded-back portion can be dealt with by a simple modification of the press die and the like, which does not require surface treatment or addition of a pressing step, so that an increase in manufacturing cost can be suppressed, and the cost is low and lightweight. There is an advantage that a cage made of pressed steel plate can be provided.

[Brief description of drawings]

FIG. 1 is a plan view showing a cage.

FIG. 2 is a sectional view showing an example.

FIG. 3 is a sectional view showing another embodiment.

FIG. 4 is a sectional view showing another embodiment.

FIG. 5 is a sectional view showing a thrust roller bearing.

FIG. 6 is a sectional view showing a conventional cage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cage 2 Steel plate 3 End surface 4, 5, 6 Bending folded part 4a, 5a Folded part 7 Pocket 8, 9 Pocket side face 10 Cylindrical roller 11 Housing 12 Shaft 13 Inner ring 14 Outer ring

Claims (1)

[Claims] 1. An end face of an annular steel plate is bent in the same direction in the thickness direction of the steel plate at the center part between the inner diameter side end part, the outer diameter side end part and the inner and outer diameter end parts, and then folded back to form the steel plate. On the end face, a plurality of pockets are formed at predetermined intervals in the circumferential direction, and the rollers housed in the pockets are held by the bent portion of the center and the side faces of the pockets on both sides of the pocket. A cage for thrust roller bearings, wherein one or both of the folded-back portions are extended in the thickness direction of the steel sheet with respect to the end surface of the steel sheet, and the extended folded-back portions serve as rotation guide surfaces for contacting other members.