JP2003028200A - One-way clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a one-way clutch capable of preventing a getting of an upper edge of a sprag into a pocket of a holder even if the sprag is slipped and the rotating moment is generated. SOLUTION: This one-way clutch is provided with the holder 3, a spring 4 to be guided by the holder 3, and the sprag fitted in a pocket of the holder and a pocket of the spring and to be energized toward a lock side by a tongue piece part formed in the spring. A projection part 3a projecting outward in the radial direction is formed in an edge of the pocket 3p of the holder 3 of the one-way clutch arranged in an annular space between an outer ring 1 and an inner ring 2.

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, and more particularly, a projection protruding radially outward is formed at an end edge of a pocket of a cage so that a sprag does not slip into the pocket of the cage. The present invention also relates to a one-way clutch with stable meshing performance.

[0002]

2. Description of the Related Art A one-way clutch used in an automatic transmission of an automobile is usually composed of a retainer 13, a spring 14 and a sprag 15, as shown in FIG.
1 and the inner ring 12 are arranged in an annular space 20, and relative rotation between the outer ring 11 and the inner ring 12 repeats rotation and locking of the inner and outer rings. That is, when the sprag 15 rotates in one direction, the outer ring 11 and the inner ring 12 integrally rotate (lock) by a wedge action.
Then, the power is transmitted, and when it is rotated in the other direction, the wedge action is released, and the vehicle idles and the power transmission is blocked (unlocked). Such a one-way clutch that repeatedly performs transmission and interruption of power is always required to have synchronism of sprag operation and proper meshing, and therefore, is devised so that other members do not interfere with sprag operation. ing.

In the above-described one-way clutch of the sprag type, the spring 14 is guided on the inner diameter side of the retainer 13, and the radial positioning of the sprag 15 held by the retainer 13 and the spring 14 is made accurate. . Further, the tongue piece 14t of the spring 14 normally gives a pre-stress (urging force) to the side that locks the sprag 15 and contributes to the meshing property. Thus, with a one-way clutch,
The outer peripheral cam surface 15a of the sprag 15 rolls on the inner peripheral surface (raceway surface) 11a of the outer ring 11 and the inner peripheral cam surface 15b forms the inner ring 12 each time the sprag 15 idles and locks repeatedly.
Rolling on the outer peripheral surface (orbital surface) 12a.

[0004]

In the sprag type one-way clutch, due to misalignment, vibration, or eccentricity between the outer ring and the inner ring, the sprag oscillates when shifting from the free rotation state to the locked state or vice versa. You may slip during the process. When such a slip occurs, a rotational moment is applied to the sprag 15 with the edge Q of the pocket 13p of the cage 13 as a fulcrum, as shown in FIG. At this time, the recess 1 of the sprag 15
5c overlaps with the edge Q of the pocket 13p of the retainer 13, and rotates in the arrow Z direction with this Q point as a fulcrum. If the pocket 13p of the cage 13 is large, there is a problem that the convex portion 15d at the upper edge of the sprag 15 may go into the inner diameter side of the pocket 13p. If such a crawling phenomenon occurs, it becomes impossible to ensure the synchronism of the sprags, which adversely affects the meshing performance. However, for the pocket 13p of the cage, the sprag 1
In order to secure the smooth operation of No. 5, a length of a certain value or more is required.

The present invention has been made in order to solve the above-mentioned problems, and secures the required length of the pocket of the cage and, even when the sprag slips and a rotational moment is generated, the upper edge of the sprag is generated. It is an object of the present invention to provide a one-way clutch whose part does not slip into a pocket of a cage.

[0006]

That is, in order to solve the above-mentioned problems, the present invention according to claim 1 provides
A retainer, a spring guided by the retainer, and a sprag that is biased toward the lock side by a pocket of these retainers and a tongue piece formed in the spring by being fitted in the pocket of the retainer. In a one-way clutch arranged in an annular space between the inner ring and the inner ring, a protrusion protruding radially outward is formed at an end of the pocket of the retainer on the lock release side. Is.

The invention according to claim 2 is characterized in that a plurality of the projections are formed in the axial direction of the end portion of the pocket on the unlocking side.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional view of a member constituting the one-way clutch of the present invention. This one-way clutch is composed of a cage 3, a spring 4 guided by the cage 3, and a sprag 5 arranged in a pocket of the cage 3 and the spring 3, and an outer ring 1 and an inner ring 2 are provided. It is arranged in the annular space 8 between. Although not shown, the retainer 3 may be an outer retainer, and an inner retainer that rotates relative to the retainer 3 may be disposed on the inner diameter side of the spring 4;
It can also be applied to a one-way clutch having such inner and outer cages. In the following description, the rocking direction in which the sprag 5 rocks and is locked by the wedge action between the sprag 5 and the inner and outer rings will be referred to as the lock side and the opposite direction as the lock release side.

A tab 3a (hereinafter referred to as a tab 3a or a projection 3a) is provided as a projection in the radially outward direction at the end of the pocket 3p of the retainer 3 on the unlocking side. Usually, the tab 3a can be formed by pressing at the same time as the pocket 3p of the cage 3 is manufactured by pressing. When such a tab 3a is formed at the end of the pocket 3p of the retainer 3, as shown in FIG. 2, when the one-way clutch changes from the locked state to the unlocked state, the sprag 5 rotates due to slippage. Even if a moment is generated, the sprag 5 still has a pocket 3p.
Before it digs in, it comes into contact with the tab 3a at the end of the pocket 3p of the cage 3.

Usually, the sprag 5 swings so that its outer cam surface 5a rolls on the inner peripheral surface 1a of the outer ring 1 and its inner cam surface 5b rolls on the outer peripheral surface 2a of the inner ring 2 to release the locked state ( The same applies when locking from a free rotation state). At this time, if the sprag 5 slips in the process of oscillating due to misalignment or vibration of the one-way clutch, or eccentricity of the outer ring 1 and the inner ring 2, the sprag 5 is connected to the edge of the pocket 3p of the cage 3. A rotational moment is applied with the point Q as a fulcrum, and the point rotates in the arrow Z direction with the point Q as a fulcrum. However, in this case, since the tab 3a is formed at the end of the pocket 3p of the cage 3 on the unlocking side in the circumferential direction, the sprag 5 comes into contact with the upper end of the tab 3a and stops at that position. . Therefore, the sprag 5 does not get into the inner diameter side of the pocket 3p.

As shown in FIGS. 3A and 3B, the protrusion 3a provided at the end of the pocket 3p of the retainer 3 on the unlocking side may be one, but FIG. A),
As shown in (B), the pocket 3p has a convex shape (a concave shape at the central portion and a step shape on both sides).
Two (a plurality of) protrusions 3b and 3c may be formed in the axial direction of the end portion on the unlocking side. In this case, pocket 3p
The tongue portion 4t of the spring 4 is located in the concave portion, and the projections 3b and 3c, which are stepped portions on both sides, serve as guide portions for the spring 4.

In this one-way clutch, the projection (tab) 3a or the projection (3) provided on the cage 3 is provided.
b, 3c) must be formed so that when the sprag 5 is freely rotated and the locked state is released, the sprag 5 comes into contact when fully released. That is, if the sprag 5 comes into contact with the upper end of the tab 3a when the locked state is not completely released, the one-way clutch will be meshed poorly.

In the above embodiment of the present invention, the cage 3
The protrusion 3a (or the protrusions 3b and 3c) provided on the end edge of the pocket 3p is not limited to the example shown in the figure. In short, it suffices to provide a protrusion that comes into contact with the pocket 3p of the cage 3 before the sprag 5 slips in when a rotational moment is generated in the sprag 5 due to slippage during swinging motion. Therefore, the protrusions (tabs) 3a (or the protrusions 3b, 3c) are a kind of protrusions that prevent the sprags 5 from going under and can have various shapes.

[0014]

As described above in detail, according to the one-way clutch of the present invention, even if the sprag slips during the swinging motion and a rotational moment is generated with the end edge portion of the pocket as a fulcrum, the sprag It is possible to prevent the end of the cam surface from coming into contact with a generally radially extending projection (tab) provided in the pocket of the cage and stopping at that position, and preventing the sprag from slipping into the pocket of the cage. Therefore, the synchronism of the sprags can be ensured and the one-way clutch with good meshing can be obtained.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a member constituting a one-way clutch of the present invention.

FIG. 2 is a partial cross-sectional view of a member constituting the one-way clutch of the present invention, showing a state in which a rotation moment is generated in a sprag and the sprag rotates and comes into contact with a protrusion of a pocket of a cage.

FIG. 3 (A) is a plan view of a retainer pocket portion and a spring portion of the one-way clutch of the present invention, and FIG. 3 (B) is a perspective view of this portion.

FIG. 4 (A) is a plan view of a cage pocket portion and a spring portion of a modified example of the one-way clutch of the present invention, and FIG. 4 (B) is a perspective view of this portion.

FIG. 5 is a partial cross-sectional view of a member constituting a conventional one-way clutch, showing a state in which a rotation moment is generated in a sprag and the sprag rotates into a pocket of a cage.

FIG. 6 is a partial cross-sectional view of a member constituting a conventional one-way clutch.

[Explanation of symbols]

1 outer ring 2 inner ring 3 cage 3a Projection (tab) 3p cage pocket 4 spring 5 sprags

Claims (2)

[Claims] 1. A retainer, a spring guided by the retainer, and a sprag urged toward the lock side by a pocket of the retainer and a tongue portion formed in the spring fitted in the pocket of the spring. And a one-way clutch disposed in the annular space between the outer ring and the inner ring, wherein a protrusion portion that projects radially outward is formed at the lock release side end of the pocket of the cage. One-way clutch featuring. 2. The one-way clutch according to claim 1, wherein a plurality of the protrusions are formed in an axial direction of an end portion of the pocket on the unlocking side.