JP2002089590A - One-way clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one-way clutch excellent in mass-productivity and causing little friction. SOLUTION: The one-way clutch includes an inner ring; an outer ring; a plurality of engagement members positioned between the inner and outer rings; a cage for retaining the engagement members; a spring for energizing each engagement member in one direction; and an end bearing of U-shaped cross section consisting of a first cylinder portion and a second cylinder portion disposed on both sides between the inner and outer rings, and an annular portion interconnecting the first and second cylinder portions, with the first cylinder portion fitted over the outer peripheral surface of the inner ring and the second cylinder portion fitted over the inner peripheral surface of the outer ring. A recess 11 is formed in at least the inner peripheral surface 8a of the first cylinder portion 8 of the end bearing 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-way clutch used for a transmission of an automobile or the like.

[0002]

2. Description of the Related Art Conventionally, as a one-way clutch used for an automobile or the like, as shown in FIG.
1, a plurality of engagement members (sprags) 52 disposed between inner and outer rings, an inner retainer 53 and an outer retainer 54, a spring 55, an end bearing 56 and the like are known. .

[0003] The sprag 52 comprises an inner race 51 and an outer race 50.
Are held by the inner retainer 53 and the outer retainer 54 in a space formed by the respective end bearings 56 fitted on both sides between the inner and outer retainers 53, and one end is provided by a spring 55 disposed between the inner and outer retainers 53 and 54. It is arranged to be urged. Further, each end bearing 56 includes a first cylindrical portion 57 fitted to the outer peripheral surface 51a of the inner ring 51, a second cylindrical portion 58 fitted to the inner peripheral surface 50a of the outer ring 50, and a first cylindrical portion 57. And an annular portion 59 connecting the second cylindrical portion 58 to the second cylindrical portion 58 in the radial direction. The annular portion 59 of each end bearing 56 having a U-shaped cross section is located outside the one-way clutch. The annular portion 59 has substantially the same thickness from the inner circumference to the outer circumference, and extends in the radial direction so as to be substantially perpendicular to the axis of the inner ring 51. Further, in each of the end bearings 56, the inner peripheral surface 57a of the first cylindrical portion 57 facing the outer peripheral surface 51a of the inner ring 51 and the outer peripheral surface 58a of the second cylindrical portion 58 facing the inner peripheral surface 50a of the outer ring 50 are formed. It is formed on a flat surface.

[0004]

In the above-described conventional one-way clutch, the end bearings 56 are provided with the inner and outer rings 51,
It is arranged between the bearings 50 and serves as a sliding bearing. That is, the inner peripheral surface 57 a of the first cylindrical portion 57 slides on the outer peripheral surface of the inner ring 51, and the outer peripheral surface 58 a of the second cylindrical portion 58 slides on the inner peripheral surface 50 a of the outer ring 50. However, the inner and outer rings 51 and 50 and the first cylindrical portion 57 of the end bearing 56
The gap between the second cylindrical portion 58 and the second cylindrical portion 58 is very small from the viewpoint of securing a space for the sprag 52 of the one-way clutch. Therefore, the friction between the inner and outer rings 51 and 50 and the first cylindrical portion 57 and the second cylindrical portion 58 of the end bearing 56, that is, the drag torque cannot be reduced, and there is a problem that seizure easily occurs. This friction is
In particular, a problem occurs between the inner ring 51 and the first cylindrical portion 57. The reason for this is that the gap between the outer ring 50 and the second cylindrical portion 58 on the side where the peripheral speed is high is usually made as small as possible and the two members 50, 58
While it is considered that there is no slip between
This is because a gap is provided between the inner ring 51 having a low peripheral speed and the first cylindrical portion 57 so that the inner ring 51 is positively slipped between the two members 51 and 57.

In order to solve the above problem, as shown in FIG. 6, an axial groove 60 is machined by turning on an inner peripheral surface 57a of a first cylindrical portion 57 of an end bearing 56 at a plurality of circumferential positions. Although a configuration for reducing the contact area has been proposed, there is a problem in that the machining of the axial groove 60 is performed by machining, which results in high cost and poor mass productivity.

[0006] In view of the above problems, an object of the present invention is to provide a one-way clutch which is excellent in mass productivity and has low friction.

[0007]

Means for Solving the Problems As means for solving the above problems, the invention of claim 1 comprises an inner ring, an outer ring, a plurality of engaging members disposed between the inner and outer rings, and holding the engaging member. Retainer, a spring for urging each engaging member in one direction, and a first cylindrical portion which is disposed on both sides between the inner ring and the outer ring and which is fitted to an outer peripheral surface of the inner ring, and an inner peripheral surface of the outer ring A one-way clutch having a U-shaped cross-section end bearing composed of a second cylindrical portion fitted to the first cylindrical portion and an annular portion connecting the first and second cylindrical portions to each other. Is characterized in that a concave portion is formed on the inner peripheral surface.

The invention according to claim 2 is characterized in that the recess is a plurality of dimple-shaped recesses.

Further, the invention according to claim 3 is characterized in that the recess is an axial groove formed by press molding.

Further, in the invention according to claim 4, the recess is formed by an axial groove formed by press molding and a circumferential groove formed by press molding so as to cross the axial groove. It is characterized by having.

Further, the invention according to claim 5 includes an inner ring,
An outer ring, a plurality of engaging members disposed between the inner and outer rings, a retainer holding the engaging members, a spring for urging each engaging member in one direction, and disposed on both sides between the inner ring and the outer ring And a first cylindrical portion fitted to the outer peripheral surface of the inner ring, a second cylindrical portion fitted to the inner peripheral surface of the outer ring, and the first and second cylindrical portions.
In a one-way clutch comprising an end bearing having a U-shaped cross section comprising an annular portion connecting the cylindrical portions, a plurality of convex portions are formed on at least an inner peripheral surface of the first cylindrical portion of the end bearing. And

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. It comprises an outer ring 1, an inner ring 2, a plurality of engaging members (sprags) 3 arranged between the inner and outer rings, an inner retainer 4 and an outer retainer 5, a spring 6, an end bearing 7, and the like. .

The sprags 3 are held by an inner cage 4 and an outer cage 5 in a space formed by end bearings 7 fitted on both sides between the inner ring 2 and the outer ring 1, and are held inside and outside. It is arranged by being biased to one side by a spring 6 arranged between the containers 4 and 5. Furthermore, each end bearing 7
A first cylindrical portion 8 fitted to the outer peripheral surface 2a of the inner ring 2;
A second cylindrical portion 9 fitted to the inner peripheral surface 1a of the outer race 1;
It has a U-shaped cross section including an annular portion 10 connecting the cylindrical portion 8 and the second cylindrical portion 9 in the radial direction. The annular portion 10 of each end bearing 7 having a U-shaped cross section is located outside the one-way clutch. The annular portion 10
Are formed to have substantially the same thickness from the inner circumference to the outer circumference, and to extend in the radial direction so as to be substantially perpendicular to the axis of the inner ring 2.

Further, the outer surface of each of the end bearings 7, that is, the inner peripheral surface 8a of the first cylindrical portion 8 facing the outer peripheral surface 2a of the inner ring 2, and the second peripheral surface 1a of the outer ring 1 facing the inner peripheral surface 1a.
Outer peripheral surface 9a of cylindrical portion 9 and outer surface 10a of annular portion 10
Has a concave portion for reducing friction. As an embodiment of this concave portion, in FIGS. 1 and 2, a large number of dimple-shaped depressions 11 are formed. The depression 11 may be formed on the inner peripheral surface 8a of the first cylindrical portion 8 and the outer peripheral surface 9a of the second cylindrical portion 9 which are sliding surfaces.
In particular, it is always necessary for the inner peripheral surface 8a of the first cylindrical portion 8. As can be understood from the description of the conventional structure, the gap between the outer ring 1 and the second cylindrical portion 9 on the side where the peripheral speed is high is usually minimized, and the slip between the two members 1 and 9 is reduced. Although it is considered not to occur, a gap is provided between the inner ring 2 having a low peripheral speed and the first cylindrical portion 8 so that both members 1
This is because it is made to slide actively between the eight.

The end bearing 7 is formed as follows. A donut-shaped disc having a predetermined length in a radial deformation direction is punched from a thin metal plate by press working.
At this time, a dimple-shaped depression 11 having a predetermined depth is simultaneously formed on the entire surface of one surface by stamping with a press. Thereafter, the inner and outer diameter portions are drawn and formed by pressing the first cylindrical portion 8 and the second cylindrical portion 9 so that the dimple-shaped depression 11 is on the outer surface side. The end bearing 7 of FIG.
Is formed. Since the dimple-shaped dent processing is performed on the entire surface, the position of the dent 11 is not considered so much, so that the die processing is easy.
Unnecessary depressions 11 are also formed in a. When it is necessary to avoid this, when punching out the above-mentioned donut-shaped disk, only the radial region to be the first cylindrical portion 8 is used.
Alternatively, the dimple-shaped dent 11 may be formed only in the radial direction regions to be the first cylindrical portion 8 and the second cylindrical portion 9. With this configuration, the depression 11 is formed only on the inner peripheral surface 8a of the first cylindrical portion 8 serving as a sliding surface, or only on the inner peripheral surface 8a of the first cylindrical portion 8 and the outer peripheral surface 9a of the second cylindrical portion 9. Will be formed. This depression 11 must be formed at least on the inner peripheral surface 8a of the first cylindrical portion 8 as described above.

FIG. 3 shows another embodiment.
A plurality of axial grooves 12 are formed on the circumference of the inner peripheral surface 8a of the cylindrical portion 8 by press working.
One circumferential groove 14 intersecting with 2 is formed by press working. This axial groove is continuous from the end of the first cylindrical portion 8 to the outer surface 10a of the annular portion 10 so that lubricating oil can flow. Further, in FIG. 3, the axial groove 12 is formed only on the inner peripheral surface 8a of the first cylindrical portion 8, but may be formed on the outer peripheral surface 9a of the second cylindrical portion 9 if necessary. Further, the entire outer surface of the end bearing 7, that is, the inner peripheral surface 8 of the first cylindrical portion 8
a, it may be formed on the outer surface 9a of the second cylindrical portion 9 and the outer surface 10a of the annular portion 10. A plurality of circumferential grooves 14 may be provided in the axial direction. Further, if necessary, either the circumferential groove 14 or the axial groove 12 may be omitted. Also,
The press forming of the axial groove 12 and the circumferential groove 14 is the same as that described with reference to FIG.

FIG. 4 shows another embodiment,
The outer surface of the end bearing 7, that is, the first cylindrical portion 8
A large number of projections 13 are formed on the inner peripheral surface 8a, the outer peripheral surface 9a of the second cylindrical portion 9, and the outer surface 10a of the annular portion 10. The convex portion 13 may be formed on the inner peripheral surface 8a of the first cylindrical portion 8 and the outer peripheral surface 9a of the second cylindrical portion 9 which are sliding surfaces. 8a is always necessary. The reason is as described in FIG. The convex portion 13 is also processed by press molding, and the processing steps are the same as those in FIG.

[0018]

The one-way clutch according to any one of the first to fifth aspects of the present invention has a concave portion formed on the inner peripheral surface of the first cylindrical portion of the end bearing, which is the side where slippage occurs. The contact area can be reduced, and the friction, that is, the drag torque can be reduced.

Further, in the one-way clutch of the second or fifth aspect, a lubricating oil film is easily formed by a large number of irregularities, and the seizure resistance can be improved.

Further, in the one-way clutch according to the third aspect, since the axial groove is formed by press molding instead of machining, excellent mass productivity and cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a one-way clutch according to an embodiment of the present invention.

FIG. 2 is a sectional view of the end bearing of FIG. 1;

FIG. 3 is a sectional view of an end bearing according to another embodiment of the present invention.

FIG. 4 is a sectional view of an end bearing according to still another embodiment of the present invention.

FIG. 5 is a sectional view of a conventional one-way clutch.

FIG. 6 is a sectional view of another end bearing of the conventional one-way clutch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer ring 2 Inner ring 3 Sprag 4 Inner cage 5 Outer cage 6 Spring 7 End bearing 8 First cylindrical part 9 Second cylindrical part 10 Annular part 11 Depression 12 Axial groove 13 Convex part

Claims (5)

[Claims] An inner ring, an outer ring, a plurality of engaging members disposed between the inner and outer rings, a retainer holding the engaging members,
A spring for urging each of the engagement members in one direction, a first cylindrical portion which is disposed on both sides between the inner ring and the outer ring, and which is fitted to the outer peripheral surface of the inner ring, and which is fitted to the inner peripheral surface of the outer ring. In a one-way clutch including a second cylindrical portion and an end bearing having a U-shaped cross section formed of an annular portion connecting the first and second cylindrical portions, at least an inner peripheral surface of the first cylindrical portion of the end bearing is provided. A one-way clutch, wherein a recess is formed. 2. The one-way clutch according to claim 1, wherein the recess is a plurality of dimple-shaped recesses. 3. The one-way clutch according to claim 1, wherein the recess is an axial groove formed by press molding. 4. The method according to claim 1, wherein the concave portion is formed by an axial groove formed by press molding and a circumferential groove formed by press molding so as to intersect the axial groove. Item 1. The one-way clutch according to Item 1. 5. An inner ring, an outer ring, a plurality of engaging members disposed between the inner and outer rings, a retainer holding the engaging members,
A spring for urging each of the engagement members in one direction, a first cylindrical portion which is disposed on both sides between the inner ring and the outer ring, and which is fitted to the outer peripheral surface of the inner ring, and which is fitted to the inner peripheral surface of the outer ring. In a one-way clutch including a second cylindrical portion and an end bearing having a U-shaped cross section formed of an annular portion connecting the first and second cylindrical portions, at least an inner peripheral surface of the first cylindrical portion of the end bearing is provided. A one-way clutch, wherein a plurality of convex portions are formed.