JPS6123865A - Starter equipped with planetary gear reduction mechanism - Google Patents

Abstract

PURPOSE:To absorb the impact in the engagement between a ring gear and a pinion by arranging an annular elastic member between an intermediate bracket for axially supporting a driving shaft and a stopper installed onto the outer periphery of the driving shaft. CONSTITUTION:One edge of a driving shaft 1 is rotatably installed with the armature shaft 3a of a starter motor 3 onto a same shaft through a bearing 1b. An annular elastic member 10 is arranged between an intermediate bracket 5 axially supporting the outer periphery of the driving shaft 1 through a bearing 9 and a stopper 16 installed onto the outer periphery of the driving shaft 1. Therefore, the impact in the engagement between a pinion 2d and a ring gear 15 can be certainly absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a starter with a planetary gear reduction mechanism for driving an internal combustion engine.

(Prior art) As shown in Japanese Utility Model Application Publication No. 58-136676, the conventional technology is to provide a groove in at least one of the front end of the armature shaft or the rear end of the drive shaft facing the armature shaft. An elastic body and a steel ball for receiving thrust load pressure urged by the elastic body are housed in the groove, and the elastic body absorbs the impact caused by the collision when the pinion meshes with the ring gear of the internal combustion engine.

However, with the above-mentioned conventional device, it is impossible for the elastic body to completely absorb the impact caused by the collision when the pinion meshes with the ring gear of the internal combustion engine. Because of this, it is necessary to strengthen the relatively weak end frame that holds one end of the armature shaft, and the elastic body constantly applies axial loads to the armature shaft and drive shaft. There was a problem in that the bearing loss of the armature shaft was large.

[Problem that the invention seeks to solve]

In view of the conventional example described above, the present invention reliably absorbs the impact when the ring gear and pinion mesh.

[Means for solving problems]

An armature shaft of a starter motor, a drive shaft disposed on the same axis as the armature shaft, a pinion connected to the outer periphery of the drive shaft by a helical spline and meshed with a ring gear of the internal combustion engine, and an end of the armature shaft of the starter motor. It has a sun gear formed on the outer periphery of the armature shaft, a planetary gear that meshes with the sun gear, and an internal gear that meshes with the planetary gear. a planetary gear reduction mechanism that reduces speed and transmits the speed to the drive shaft; an intermediate bracket that pivotally supports the outer periphery of the drive shaft via a bearing; a stopper provided on the outer periphery of the drive shaft;
A starter with a planetary gear reduction mechanism includes: an annular elastic member inserted between the stopper and the intermediate bracket on the outer peripheral side of the drive shaft.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

In FIG. 1, a spline tube 2a is helically spline connected to a helical spline 1a formed on the outer periphery of a drive shaft 1. As shown in FIG.

A stepped portion 1e is formed on the outer periphery of the helical spline 1a of the drive shaft 1 on the side of the starter motor 3, which contacts the end of the spline tube 2a. Further, the inner circumference of a thalassocia outer 2e integrally formed with this spline tube 2a is connected to a pinion 2d via a roller 2b and a clutch inner 2C. A one-way clutch 2 is constituted by the clutch outer 2810-ra 2b and the clutch inner 2C. Further, one end of the drive shaft 1 is connected to a starter motor 3 on the same axis via a bearing 1b.
It is rotatably assembled with the armature shaft 3a.

Furthermore, the other end of the drive shaft is rotatably and slidably held in a housing 11 via a bearing 9.

The starter motor 3 is connected to a magnet switch 12. Further, an end frame 4 that holds one end of the armature shirt 3a is attached to the end surface of the starter motor 3. and pinion 2 of armature shaft 3a
A sun gear 3b is formed on the outer periphery of the d-side end. Also,
A planetary gear 6 meshes with the outer periphery of this sun gear 3b. The side of the planetary gear 6 opposite to the armature shaft 3a is
It meshes with an internal gear 5a formed on an intermediate bracket 5 fixed to the housing 11. The end of the intermediate bracket 5 rotatably holds the drive shaft 1 via a bearing 1c. Further, a pin 8 is arranged on the inner circumference of the planetary gear 6 via a bearing 7. The pin 8 is press-fitted into a hole in a protrusion 1d that protrudes in the outer circumferential radial direction at the end of the drive shaft 1 on the side of the starter motor 3. Further, the sun gear 3b, intermediate bracket 5, planetary gear 6, and internal gear 5a constitute a planetary gear reduction mechanism.

A stop collar 16 serving as a stopper is attached to the outer periphery of the drive shaft 1. Further, an annular rubber 10 serving as an elastic member is attached to the outer periphery of the drive shaft 1 between the stop collar 16 and the intermediate bracket 5 via a thrust washer 17. Furthermore, there is a slight gap between the rubber 10 and the thrust washer 17.

Here, the clearance A between the inner peripheral end 1f of the drive shaft 1 and the end surface 3C of the armature shaft 3a corresponding to this end 1f is assumed to be larger than the distance that the drive shaft 1 moves toward the scooter motor 3. It is.

Next, the operation of the above configuration will be explained.

When the magnetic switch 12 is activated, the lever 13 is pulled toward the magnetic switch 12, causing the pinion 2d to move forward via the one-way clutch 2. Immediately before the pinion 2d contacts the ring gear 15 of the internal combustion engine,
The contact of the magnet switch 12 closes, driving the starter motor 3.

Then, the armature shaft 3a rotates, this rotation is decelerated via the planetary gear reduction mechanism, and the drive shaft 1
give to The rotation of the drive shaft 1 is applied to the nion 2d via the helical spline la and the one-way clutch 2. Further, when the pinion 2d comes into contact with the ring gear 15, which is not yet rotating, an impact torque in the axial direction is generated. This impact torque acts to move the drive shaft 1 toward the starter motor 3 in the axial direction F via the one-way clutch 2 and the helical spline, thereby moving the drive shaft 1 in the direction of the arrow. At this time, the annular rubber 10 disposed between the stop collar 16 and the intermediate bracket 5 undergoes elastic deformation and absorbs the impact torque. Further, due to the clearance A, even if an impact torque is applied in the axial direction F, the inner circumferential end surface 1r of the drive shaft 1 comes into contact with the armature shaft end surface 3C, and it is possible to prevent the impact torque from being transmitted to the armature shaft 3a. . Therefore, since no axial impact torque is applied to the end frame 4 of the starter motor 3, reinforcement of the end frame 4 is not required, and the end frame 4 can be made inexpensive. Further, since the annular rubber 10 constituting the elastic member is not in contact with the rotating thrust washer 17, bearing loss of the armature shaft 3a can be prevented. Since the annular rubber 10 is installed on the outer periphery of the drive shaft 1, the cross-sectional area of the annular rubber 10 for absorbing impact torque can be made thicker, and the impact torque can be reliably absorbed. do.

Note that in another embodiment shown in FIG. 2, the planetary gear 6
A holding member 18 for holding the motor 3 is disposed on the scooter motor 3 side via the bearing 7, and its end portion is fixed between the housing 11 and the motor yoke lla. The internal gear 5a that meshes with the planetary gear 6 is connected to the drive shaft 1.
is integrally formed.

Further, an intermediate bracket 19 disposed on the side opposite to the starter motor 3 of the internal gear 5a has one end fixed to the housing 11, and the other end rotatably holds the drive shaft l via a bearing IC. . A protrusion 20 serving as a stopper is integrally formed on the outer periphery of the drive shaft l, and an annular rubber 10 is disposed between the protrusion 20 and the intermediate bracket 19 via a thrust wansha 17. .

Further, in the above embodiment, the annular rubber 10 is used as the elastic member, but the elastic member may be an elastic body such as a coil spring or a disc spring.

Further, the one-way clutch 2 includes an armature shaft 3
It may be installed anywhere between the a side and the pinion 2d.

As long as the elastic member is inserted between the stopper and the intermediate bracket in an uncompressed state, the elastic member may be slightly in contact with the stopper and the intermediate bracket.

〔Effect of the invention〕

As described above, in the present invention, since the annular elastic member is disposed between the intermediate bracket that pivotally supports the outer periphery of the drive shaft via a bearing and the stopper provided on the outer periphery of the drive shaft, The elastic member absorbs the impact when the pinion and ring gear engage, and the impact is not transmitted to the end frame via the armature shaft, eliminating the need for reinforcement of the end frame, etc.
This has the advantage that the end frame can be made inexpensive, and the area of the annular elastic member that absorbs impact can be made large, so that impact can be reliably absorbed.

[Brief explanation of drawings]

FIG. 1 is a partially sectional front view showing an embodiment of the device of the present invention;
FIG. 2 is a longitudinal sectional view showing the main parts of another embodiment of the device of the present invention. 1... Drive shaft, 1a... Helical spline, 2d... Pinion, 3... Starter motor,
3a... Armature shaft, 5, 19... Intermediate bracket, 10... Annular rubber forming an elastic member, 3b
. 5a, 6... sun gear, internal gear, planetary gear, respectively constituting the planetary gear mechanism, 15... pinion, 16.20... stop collar without stopper,
Protrusion.

Claims (1)

[Claims] An armature shaft of a starter motor, a drive shaft disposed on the same axis as the armature shaft, a pinion connected to the outer periphery of the drive shaft by a helical spline and meshing with a ring gear of an internal combustion engine, and a starter motor. The motor includes a sun gear formed on the outer periphery of an end of an armature shaft, a planetary gear that meshes with the sun gear, and an internal gear that meshes with the planetary gear, and the motor is connected to the motor through the sun gear, the planetary gear, and the internal gear. , a planetary gear reduction mechanism that reduces rotation of the armature shaft and transmits the rotation to the drive shaft; an intermediate bracket that pivotally supports the outer periphery of the drive shaft via a bearing; and a stopper provided on the outer periphery of the drive shaft. A starter with a planetary gear reduction mechanism, comprising: an annular elastic member inserted between the stopper and the intermediate bracket on the outer peripheral side of the drive shaft.