JPH0681862A - Starter clutch - Google Patents

Abstract

PURPOSE:To provide a starter clutch having a seal structure with a small number of part items and easy to manufacture. CONSTITUTION:An external peripheral part is secured to an external peripheral surface of a clutch outer l, in a clutch cover 5, to arrange its ring plate part 52 by facing its internal peripheral end to an external peripheral surface of a clutch inner 2 through specified fine clearance, and thus, centering of the clutch inner 2 by the clutch cover 5 can be performed. Simultaneously with the above, the clutch cover 5 supports an elastic annular seal member 6, and its internal peripheral end is brought into light contact with the external peripheral surface of the clutch inner 2, to seal a ring-shaped space D.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a starter clutch.

[0002]

2. Description of the Related Art Conventionally, a starter clutch, that is, an overrunning clutch for a starter, is provided in the vicinity of an open end surface of the clutch outer in order to close a ring-shaped gap between a clutch outer that houses a clutch roller and a clutch spring and a clutch inner. A washer is fitted on the clutch outer cover and the outer periphery of the washer are covered with a clutch cover for fixing the washer.

However, in recent years, the use environment of the starter has become harsh with the increase in output and rotation of the engine. In particular, if the grease filled in the annular gap leaks to the outside due to high temperature, high vibration, water infiltration, etc., the wear of the clutch roller, etc. is promoted and the clutch life is shortened. As a result, sliding failure of the clutch roller or the like occurs, but in the above-mentioned conventional starter clutch, such grease leakage and water infiltration were insufficient.

In Japanese Utility Model Application Laid-Open No. 64-11369, in order to seal the ring-shaped gap, a ring-shaped step recess is formed in the opening end surface of the clutch outer, and an O-shaped recess is formed on the back end surface of the step recess.
After fitting the ring, close the stepped recess with a lid, insert a seal member between the inner surface of the lid and the outer surface of the clutch inner, and use the clutch cover to prevent the lid from coming off. There is. That is, in this prior art, the O-ring seals the gap between the lid and the clutch outer, the oil seal seals the gap between the lid and the clutch inner, and the lid fitted in the stepped recess is the core of the clutch inner. It is also configured to put out.

[0005]

However, in the seal structure of the above publication, although the seal of the annular gap and the centering of the clutch inner are possible, the O-ring, the oil seal and the lid having a complicated shape are provided. Required, the number of parts is large, and the processing of the lid, which requires high precision, is complicated, which has been a factor of increasing the manufacturing cost.

It is to be noted that the above-mentioned cover having a complicated shape is required because the cover presses the O-ring at the outer peripheral side portion of the inner end surface thereof, and the oil seal is applied to the inner peripheral side portion of the outer end surface thereof. Of the clutch inner, the outer peripheral portion of the outer end surface thereof receives an axial force for pressing the O-ring, and the inner and outer peripheral surfaces thereof contact the outer peripheral surface of the clutch inner and the inner peripheral surface of the clutch outer. This is because it must be realized.

The present invention has been made in view of the above problems, and an object thereof is to provide a starter clutch having a seal structure having a small number of parts and easy to manufacture.

[0008]

A starter clutch according to the present invention has a cylindrical clutch inner disposed coaxially with an output shaft, and an inner peripheral surface disposed coaxially with the output shaft and the clutch inner. A clutch outer having a one-end opening tubular shape that faces the outer peripheral surface of the clutch inner via a ring-shaped gap, and a clutch roller and a clutch spring housed in the ring-shaped gap and transmitting torque in one direction between the clutch inner and the clutch outer. A starter clutch having an outer peripheral portion fixed to the outer peripheral surface of the clutch outer to shield the opening of the clutch outer, an outer peripheral portion fixed to the clutch cover, and an inner peripheral end of the clutch inner. An elastic annular seal member is provided to lightly contact the outer peripheral surface to seal the annular gap, and End is characterized by facing with a predetermined small gap to the outer circumferential surface of the clutch inner.

[0009]

The inner peripheral edge of the clutch cover, the outer peripheral portion of which is fixed to the outer peripheral surface of the clutch outer, is disposed so as to face the outer peripheral surface of the clutch inner with a predetermined minute gap, whereby the clutch inner of the clutch cover is formed. Enables centering. At the same time, the clutch cover carries an elastic annular seal member, and the inner peripheral end of this elastic annular seal member makes light contact with the outer peripheral surface of the clutch inner to seal the annular gap.

[0010]

As described above, in the starter clutch of the present invention, the inner peripheral end of the clutch cover is formed so that it can be centered, and the inner peripheral portion of the clutch cover carries the elastic annular seal member for sealing. Since the construction is adopted, it is possible to favorably prevent water ingress and grease outflow, and since the seal structure is not provided in the annular gap, it is possible to sufficiently fill the annular gap with grease. Further, by aligning the clutch inner with the clutch inner,
It is also possible to reduce the frictional resistance with the ruler member and reduce the wear thereof.

Further, the above-mentioned sealing and waterproofing can be realized with a simple shape and a small number of parts, and the excellent effect that the centering at the time of assembling the clutch inner is also possible can be achieved.

[0012]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to FIG. This starter clutch is a one-way roller clutch (overrunning clutch) for starting an engine for a vehicle, the upper half of which is shown in cross section. The clutch outer 1 and the clutch inner 2 are fitted to the output shaft of a starter motor (not shown). And the clutch clearance is provided in the annular gap D between the clutch outer 1 and the clutch inner 2.
The rotor 3 and a clutch spring (not shown) are housed. Further, the opening of the ring-shaped gap D is closed by a half washer 4 for preventing the roller from coming off, the half washer 4 is fixed by a clutch cover 5, and a lip seal (an elastic annular seal member in the present invention) is attached to the clutch cover 5. 6 is fixed.

The clutch outer 1 is a substantially bowl-shaped cylindrical member having a wedge-shaped inner wall, and a small diameter cylindrical portion 11 is provided so as to project axially outward from a central portion of the bottom surface of the bowl. A helical spline groove 12 that fits into a helical spline groove (not shown) of the output shaft is engraved on the peripheral surface. The clutch inner 2 has a sleeve shape with a gear, and in the figure, a substantially right half is coaxially fitted in a bowl of the clutch outer 1, and a right end surface of the clutch inner 2 is in relative rotation contact with a bowl bottom of the clutch outer 1. A pinion gear 21 is provided at the left end of the outer peripheral surface of the clutch inner 2. The pinion gear 21 is axially left-movable integrally with the starter clutch so as to be able to mesh with a ring gear (not shown) on the engine side. The bearing 8 is fitted in the left half of the inner peripheral surface of the clutch inner 2.
An output shaft (not shown) is fitted in the bearing 8, whereby the clutch inner 2 is rotatable relative to the output shaft. At the axial center of the outer peripheral surface of the clutch inner 2,
A circular brim portion 22 is provided so as to project in the centrifugal direction by cold forging or the like, and the left end surface of the circular brim portion 22 in the figure is integrated with the right end of the pinion gear 21. Further, an annular groove 23 is provided in the central portion of the outer peripheral surface of the clutch inner 2 in the axial direction adjacent to the right end of the circular collar portion 22.

The bowl-shaped space between the clutch inner 2 and the clutch outer 1 is a ring-shaped gap D which is open at one end. In this ring-shaped gap D, a cylindrical clutch roller 3 and a clutch spring (not shown) are arranged. Has been done. The inner wall of the clutch outer 1 is formed in a wedge shape, and a cylindrical clutch roller 3 is pressed against the wedge-shaped portion by a clutch spring (not shown), so that the clutch outer 1
It is possible to transmit the driving torque of the above to the clutch inner 2. Then, when the clutch inner 2 rotates at a higher speed, the pressing of the clutch roller 3 by the clutch spring is deenergized, and the torque transmission from the clutch inner 2 to the clutch outer 1 becomes impossible.

The half washer 4 is fitted in the annular groove 23 of the clutch inner 2 and is restricted from moving in the axial direction. The outer periphery of the right end surface of the half washer 4 in the drawing is the left end of the clutch outer 1. Is in contact with the surface (open end surface),
As a result, the half washer 4 closes the annular gap D,
The clutch roller 3 and the clutch spring are prevented from deviating from the annular gap D. Further, grease is enclosed in the ring-shaped gap D.

The clutch cover 5 comprises a thin cylindrical portion 51 fitted and crimped on the outer peripheral surface of the clutch outer 1, and a thin wheel plate portion 52 extending radially inward from the left end of the cylindrical portion 51. The right end portion of the cylindrical portion 51 is crimped to the right end surface of the clutch outer 1. In addition, the outer peripheral portion 5 of the wheel plate portion 52
2a is curved toward the pinion gear 2a, and the wheel plate portion 52a
The center part and the inner peripheral part in the radial direction have a flat plate shape and are in contact with the half washer 4 by caulking (the half washer 4 is held together with the clutch outer 1). Furthermore,
The inner peripheral end portion 52a of the wheel plate portion 52 is bent toward the pinion gear 21 side to have a cylindrical shape, and the inner peripheral end portion 52a faces the outer peripheral surface of the circular flange portion 22 of the clutch inner 2 with a minute gap. ing. Therefore, the clutch cover 5 has a function of preventing the half washer 4 from coming off, and also has a function of centering the clutch inner 2.

The lip seal 6 is composed of a ring-shaped member made of soft rubber, and is a wheel plate portion 52 of the clutch cover 5.
Is adhered to the left end surface of the lip seal 6, and the inner peripheral end of the lip seal 6 is in light contact with the outer peripheral surface of the circular flange 22 of the clutch inner 2. The starter clutch is assembled as follows. First, the clutch roller 3 and the clutch spring are housed in the clutch outer 1, the clutch inner 2 is fitted in the annular gap D in the clutch outer 1, and the half washer 4 is held. In this state, the clutch inner 2 is fitted in the annular gap D in the clutch outer 1, and then the clutch cover 5 with the lip seal 6 is fitted in the clutch outer 1 and the clutch cover 5 is caulked to complete the assembly. .
In the starter clutch of this embodiment configured as described above, the inner peripheral end portion 52a of the wheel plate portion 52 of the clutch cover 5 is formed.
Plays a centering function for holding the clutch inner 2 coaxially with the clutch outer 1. By this centering, the contact state between the clutch inner 2 and the lip seal 6 can always be kept in a light contact state, and therefore the durability of the lip seal 6 is improved. Further, the clutch cover 5 functions as a support member for the lip seal 6, and the lip seal 6 prevents the grease enclosed in the ring-shaped gap D from leaking out and prevents water from entering the ring-shaped gap D. Therefore, the starter clutch of this embodiment has a simple structure, a small number of parts, a light weight and a small size, and a simple manufacturing process.

(Embodiment 2) Contrary to Embodiment 1, this embodiment uses the clutch outer 101 on the pinion side and the clutch inner 102 on the armature side. In this case, the pinion gear is on the clutch outer 101 side. Since there is a 101b, a flat washer 10 is used instead of the half washer 4.
4 can be adopted. Reference numeral 105 is a clutch cover, and 106 is a lip seal (elastic annular seal member) fixed to the clutch cover 105.

[Brief description of drawings]

FIG. 1 is a half sectional view showing an embodiment of a starter clutch of the present invention,

FIG. 2 is a half sectional view showing another embodiment of the starter clutch of the present invention.

[Explanation of symbols]

1 is a clutch outer, 2 is a clutch inner, 3 is a clutch roller, 4 is a half washer, 5 is a clutch cover,
6 is a lip seal (elastic ring seal member).

Claims (1)

[Claims] 1. A cylindrical clutch inner disposed coaxially with an output shaft, and an inner peripheral surface disposed coaxially with the output shaft and the clutch inner, with an outer peripheral surface of the clutch inner interposed via a ring-shaped gap. A cylindrical clutch outer that is open at one end, a clutch roller and a clutch spring that are housed in the annular gap and that transmit torque in one direction between the clutch inner and the clutch outer, and an outer peripheral portion on the outer peripheral surface of the clutch outer. In a starter clutch including a clutch cover that is fixedly attached to shield the opening of the clutch outer, the outer peripheral portion is fixedly attached to the clutch cover, and the inner peripheral end is in slight contact with the outer peripheral surface of the clutch inner to seal the annular gap. And an inner peripheral end of the clutch cover is provided on the outer peripheral surface of the clutch inner by a predetermined amount. Starter clutch, wherein the facing through the gap.