JPS6128756A - Starter with planet gear reduction mechanism - Google Patents

Abstract

PURPOSE:To secure the action of a clutch and transmit the power by arranging the one-way clutch between an internal gear constituting a planet gear reduction mechanism and the stationary side in the starter of an internal-combustion engine. CONSTITUTION:A sun gear 1a is formed around the armature shaft 1 of a starter motor, and an output shaft 2 is arranged coaxially wih the shaft 1. A planet gear reduction mechanism is constituted with the sun gear 1a, a planet gear 3, and an internal gear 4a. A one-way clutch is constituted with a clutch inner 4, a roller 11, a spring 12, and a clutch outer 10, and the rotary power is transmitted only toward the output shaft 2 from the armature shaft 1. Accordingly, the action of the one-way clutch is secured, and the power can be reliably transmitted.

Description

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

[Prior art]

In the conventional type, as shown in Japanese Patent Publication No. 36-4310, a plurality of clutch outers (having wedge chambers formed on the inner circumference) are disposed on the outer circumference of the armature shaft of the armature, and the armature shaft and the wedge chamber are connected to each other. In between, a roller is inserted that transmits rotation in only one direction.A sun gear is formed on the outer periphery of the clutch outer, and an internal gear is connected to this sun gear through an annular space. A planetary gear is meshed between them.

However, in the conventional system described above, the roller is inserted before the rotation of the armature shaft is decelerated via the planetary gear, so the rotation speed applied to the roller is high, and the roller is subject to centrifugal force. Under the influence of this, the clutch outer and armature shaft may become unlocked, causing the problem that power cannot be transmitted reliably.

[Problem that the invention seeks to solve]

In view of the above-mentioned conventional example, the present invention is intended to ensure the operation of the rollers. - [Means for solving the problem] An armature shaft of the starter motor, a sun gear provided on this armature shaft, an internal gear installed on this sun gear via an annular space, and meshing with each of the above gears. , a plurality of planetary gears arranged on the circumference,
An output shaft connected to the planetary gears and coaxially arranged with the armature shaft, a pinion fitted to the output shaft so as to be movable in the axial direction, and the outer periphery of the internal gear and the fixed side. The present invention is to provide a starter with a planetary gear reduction mechanism, which is provided with a one-way clutch that is disposed in the armature shaft and transmits rotational power from the armature shaft only in the direction of the output shaft.

〔Example〕

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

As shown in FIGS. 1 to 3, 1 is an armature shaft of a scooter motor, 1a is a sun gear formed on the outer periphery of the armature shaft 1, and 2 is arranged on the same axis as the armature shaft 1 via a bearing 2a. A flange portion 2b is formed at the starter motor side end, and the other end is held in the housing 8 via a bearing 8a. A plurality of planetary gears 3 are attached to the flange portion 2b of the output shaft 2 by pins 3a, and mesh with the sun gear 1a. Reference numeral 4 designates an annular clutch inner having an internal gear 4a that meshes with the planetary gear 3 formed on its inner peripheral surface. The sun gear la and the planetary gear 3 internal gear 4a constitute a planetary gear reduction mechanism. Reference numeral 5 designates a spline tube having a helical spline 5a on its inner periphery that is coupled to a helical spline 2c formed on the outer periphery of the output shaft 2, and 6 a binion integrally formed at the end of the spline tube 5, which is connected to an internal combustion engine (not shown). meshes with the ring gear. Reference numeral 7 denotes an intermediate bracket, which holds the output shaft 2 via a bearing 7a. Wedge chambers 9 are formed at equal intervals on the outer periphery of the clutch inner 4. Further, an annular clutch outer 10 serving as a fixed side is arranged around the outer periphery of the clutch inner 4 with a slight gap therebetween.

A roller 11 is inserted between the wedge chamber 9 of the clutch inner 4 and the inner peripheral surface of the clutch outer 10. This roller 11 is pressed against the narrow space of the wedge chamber 9 by a spring 12. A clutch inner 4 and a clutch outer 1 are provided at the axial end of the roller 11.
A bearing 12 with 0 is provided. Furthermore, ring-shaped thrust washers 13 are arranged at the axial ends of the clutch inner 4, the bearing 12, and the clutch outer 10, respectively, to restrict the movement of the clutch inner 4 in the axial direction.

Then, between the housing 8 and the yoke 14 of the scooter motor, the end of the intermediate bracket 7 and the thrust washer 1
3. The clutch outer 10 and the thrust washer 13 are pressed and clamped with through bolts or the like and fixed. at the same time,
The roller 11, bearing 12, and clutch inner 4 are also fixed. And clutch inner 4, roller 11,
The spring 12 and the clutch outer 10 constitute a one-way clutch. Further, one end of a lever 15 is engaged with the outer periphery of the spline tube 5, and the other end is engaged with a plunger of a magnetic switch 16. When the contact of the magnetic switch 16 closes, energization of the scooter motor starts.

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

The starter inch is closed and the magnetic switch 16 is activated to attract the plunger. This plunger suction rotates the lever 15 and moves the pinion 6 toward the ring gear. Then, just before the pinion 6 comes into contact with the ring gear, the contacts of the magnetic switch 16 are closed to drive the starter motor. The armature shaft rotates by driving the starter motor. and the second
As shown in the figure, the rotation of the armature shaft 1 in the direction of arrow A is transmitted to the planetary gear 3 in the direction of arrow B via the sun gear 1a. This rotation of the planetary gear 3 in the direction of arrow B applies force to the clutch inner 4 in the direction of the arrow. Then, the roller 11 is pushed into the narrow space of the wedge chamber 9 and wedged between the clutch inner 4 and the clutch outer 10 and locked, and the self-latch inner 4 is prevented from rotating, and the clutch inner 4 formed on the inner periphery of the clutch inner 4 is locked. The internal gear 4a is fixed. The rotation of the armature shaft 1 is then decelerated and transmitted to the output shaft 2 via the planetary gear 3 moving in the direction of arrow C.

This reduced rotation is transmitted to the output shaft 2, a spline tube 5 connected by a helical spline, and a pinion 6. Then, the rotation of the pinion 6 starts the ring gear of the internal combustion engine.

Next, FIG. 3 shows an overrun situation, in which when an excessive rotational force is transmitted from the ring gear of the internal combustion engine (not shown) to the pinion 6, the output shaft 2 rotates at a high speed. At this time, if the rotation speed of the output shaft 2 becomes larger than the rotation speed after deceleration of the armature shaft l of the starter motor, the planetary gear 3
When the rotational speed of the output shaft 2 becomes lower and the rotational speed of the output shaft 2 becomes higher, the planetary gear 3 reverses and rotates in the direction of the arrow E. When the rotation speed of the output shaft 2 becomes larger than the rotation speed of the armature shaft 1 after deceleration, a force acts on the clutch inner 4 in the direction of arrow F, so that the clutch inner 4 and the clutch outer 1
The roller 11 wedged between the clutch inner 4 and the clutch outer 10 moves to the wide space of the wedge chamber 9 and releases the lock between the clutch inner 4 and the clutch outer 10. The clutch inner 4, which is formed by the internal gear 4a, rotates in the direction of arrow F and idles, thereby preventing excessive rotational force from the internal combustion engine from being transmitted to the armature shaft.

As explained above, according to the present invention, since the one-way clutch is provided between the internal gear 4a of the planetary gear mechanism and the clutch outer 10, the axial length can be shortened, and the armature shaft 1 When transmitting the rotation of the pinion 6 to the output shaft 2, the roller 11 can reliably lock the clutch inner 4 and the clutch outer 10 without being affected by centrifugal force. Since it does not move with movement, the inertial weight can be reduced and the meshing between the pinion and the ring gear can be ensured.

In the above embodiment, the wedge chamber 9 is formed on the outer periphery of the clutch inner 4, but the wedge chamber 9 may be formed on the inner periphery of the clutch outer 10, and the roller 11 may be inserted therein.

Further, although the clutch outer 10 is formed as a separate annular body, the inner circumferential surface of the housing 8 or yoke 14 forming the fixed side may be used.゛Furthermore, a wedge chamber 9 is provided and a roller 11 is inserted into this wedge chamber 9 to constitute a one-way clutch, but if it has the function of transmitting rotation only in one direction, it may be different. A one-way clutch may be provided on the outer periphery of the internal gear.

[Effects of the Invention] As described above, in the present invention, since the one-way clutch is disposed between the internal gear constituting the planetary gear reduction mechanism and the fixed side, the axial length can be shortened. ,
And when transmitting the rotation of the armature shaft to the output shaft,
Since the one-way clutch is not affected by centrifugal force, there is an excellent effect that the one-way clutch can operate reliably.

[Brief explanation of drawings]

Fig. 1 is a partially sectional front view showing an embodiment of the starter of the present invention, Fig. 2 is a cross-sectional view showing the state of the starter in the above embodiment when it is driven, and Fig. 3 shows the overrun state of the above embodiment. FIG. 1... Armature shaft, la... sun gear, 2
...Output shaft, 3.. Planetary gear, 4a.. Internal gear, 6.. Pinion, 10.. Clutch outer forming the fixed side, 11.. Roller.

Claims (1)

[Claims] An armature shaft of the starter motor, a sun gear provided on this armature shaft, an internal gear installed on this sun gear via an annular space, and a plurality of planetary gear and
An output shaft connected to this planetary gear and arranged coaxially with the armature shaft, a pinion fitted to this output shaft so as to be movable in the axial direction, and arranged between the outer periphery of the internal gear and the fixed side. A starter with a planetary gear reduction mechanism, which is equipped with a one-way clutch that transmits rotational power from the armature shaft only in the direction of the output shaft.