JPS5969536A - Overrunning clutch for starter - Google Patents

Abstract

PURPOSE:To improve the strength of a clutch outer casing, reduce the wall thickness and weight, and improve machinability by fixing a ring made of a material with less moldability but sufficient hardness on the outer periphery of said clutch outer casing made of a soft material with good moldability. CONSTITUTION:When the turning force of a starter motor is applied to a shaft 7, rotation is transmitted to a clutch outer casing 2 through the helical spline 1a of a tube 1 opposing to the hilical spline 7a on a shaft 7, and the rotation is further transmitted to an inner casing 8 through rollers 4, driving an engine ring gear through a pinion 3 provided on the other end of the inner casing 8. Said outer casing 2 is made of a relatively soft material etc. with good machinability and on its outer periphery is fixed a ring 5 made of a material with less moldability but sufficient hardness, by means of shrinkage fit, etc. Thereby the strength of said outer casing 2 is improved and its wall thickness and weight can be reduced, while improving the machinability of a clutch cam chamber 2a, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an overrunning clutch for a starter.

In conventional overrunning clutches, the thalassocia outer is generally cold-formed, but since the cam chamber shape is complex and requires high-precision molding, a comparatively better cold-forming process is used. Soft materials are used.

However, since it is necessary to increase the wall thickness of the outer layer in order to hear the hiss when the starter is locked (1), there is a drawback that the overall physique becomes larger and the weight becomes heavier.

In order to solve the above-mentioned drawbacks, the present invention shrink-fits a ring-shaped member made of a hard material (for example, carbon fiber built-in metal, silicon carbide ceramic, high carbon steel, etc.) to the outer periphery of the clutch outer portion, or By fixing by press-fitting, etc., the strength is improved, and by doing so, the overall thickness of the thalassocia outer can be reduced and the weight can be reduced.
At the same time, it is possible to use a relatively soft material with good workability and a member that is easy to form, such as a sintered material, for the clutch outer portion, so that the workability of the thalassochicum chamber, etc. can be improved.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention shown in the drawings will be described. 1st
The figure is a cross-sectional view of essential parts showing an embodiment of an overrunning clutch embodying the present invention, and Figure 2 is a line AA shown in Figure 1.
A cross-sectional view along the line is shown. 1 is a spline tube, and 2 is a clutch outer portion formed integrally with the tube 1, and a cam chamber 2a is formed on the inner periphery. 3 is a pinion, 4 is a roller stored in the cam chamber 2a (2), 5 is a ring fixed to the outer periphery of the outer part 2 by shrink fitting or press fitting, 6 is a clutch cover, and by tightening, The entire clutch is assembled and maintained. 7 is a shaft 7a that is rotationally driven by a starter motor.

1a is a helical spline formed on the outer periphery of the shaft 7 and the inner periphery of the tube 1, and 8 is a thalassochi inner integrally molded with the binion 3. The clutch outer portion 2 is made of a relatively soft material with good workability (for example, steel for cold forging) or an easily molded material such as sintered metal. Further, the ring 5 is made of a hard material with poor formability (for example, carbon fiber-embedded metal, silicon carbide ceramic, high carbon steel, etc.).

Next, the operation of the above configuration will be explained. When the rotational force of a starter motor (not shown) is applied to the shaft 7, the rotation is transmitted to the outer portion 2 via the helical spline 1a of the tube 1 opposite to the helical spline 7a on the shaft 7. 4, the rotation is transmitted to the inner 8 (3), and the pinion 3 provided at the other end of the inner 8 drives an engine ring gear (not shown).
．． The engine reaches a complete explosion.

Note that as shown in FIG. 3, the cover 6' is attached to the outer part 2.
By press-fitting and fixing between the upper stepped portion 1b and the ring 5, it is possible to downsize the cover 6'.

Alternatively, as shown in FIG. 4, the ring 5 and the tube 1 may be integrally molded, and the outer portion 2 made of a sintered material or an easily moldable material may be press-fitted into the inner periphery of the ring 5.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing the first embodiment of the device of the present invention, and the second
The figure is a cross-sectional view taken along the line A--A shown in FIG. 1, and FIGS. 3 and 4 are longitudinal sectional views showing the configuration of essential parts of two other embodiments of the apparatus of the present invention. 2...Clutch outer part, 2a...Cam chamber, 5.
··ring. Representative Patent Attorney Takashi Okabe (4) Figure 1 Figure 3 Figure 2

Claims (1)

[Claims] An overrunning clutch for a starter that has a thalassocia outer part with a double structure consisting of a ring made of a hard material with poor formability and a clutch outer part made of a relatively soft material with good formability and having a cam chamber formed on the inner periphery.