JPS6053791B2 - Pinion transmission device for starter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a starter pinion transmission device, and more particularly to a starter pinion transmission device suitable for a starter, which incorporates a set of reduction gears between an armature and a pinion gear.

A conventional starter pinion transmission device will be explained with reference to FIGS. 1, 2, and 4.

This transmission device includes a main body 1, a motor 2, a one-way clutch 3,
It is composed of a reduction gear 4, a pinion shaft assembly 5, a shift lever assembly 6, a magnetic switch 7, and the like. The main body 1 supports a motor 2, a pinion shaft assembly 5, a shift lever assembly 6, a magnetic switch 7, and the like.

The motor 2 includes an armature 10, an armature shaft 11, an armature gear 12, a field coil 13, and the like.

On the other hand, the clutch assembly 3 includes a clutch outer 15, a roller 16, and a clutch inner 17, and the clutch inner 17 is supported by the main body 1 by ball bearings 18 and 19 on the left and right sides.

Further, a clutch cover 21 is fixed inside the clutch outer 15 and has a plain metal 20 on the inner periphery to seal several rollers 16 and a lubricant, and which is slidably engaged with the clutch inner 17. Furthermore, a plain metal 22 that is slidably fitted to the clutch inner 17 is press-fitted into the other inner peripheral portion of the clutch outer 15. The speed reduction device 3 is composed of an armature gear 12 at the tip of an armature shaft 11 and a clutch gear 23 cut into the outer surface of a latch outer 15 that meshes with the armature gear 12.

The pinion shaft assembly 5 is the pinion shaft 2
5. Consists of pinion shaft return spring 26, stopper 27, and clip 28.

The pinion shaft 25, which has a pinion 29 at its tip, is screwed into the clutch inner 17 by a helical spline 30 in the center, and is supported by left and right journal parts 31, 32 of the helical spline 30, so that the pinion shaft 25 is axially It has a structure that allows it to be moved and rotated to transmit power unilaterally.

Note that a clip 2 is attached to the opposite pinion part of the pinion shaft 25.
A pinion shaft 25
is always biased to the left and is screwed together with the clutch inner 17 by a helical spline 30. magnetic switch,
The shift lever 38 consists of a plunger, a holder 41, a hole 42, and a shift lever 38. The shift lever 38 has a substantially central portion 38a that serves as a rotation fulcrum and is pressed against the main body 1, and its upper end 38b is inserted into a hole 42 of a holder 41 that is integrated with a plunger (not shown) of the magnetic switch 7.
Both the holder 41 and the shift lever upper end 38b are biased to the right by the torsion spring, and the tip of the holder 41 abuts against the main body. The other end 38c of the shift lever 38 is located near the opposite end 25a of the pinion shaft 25. Next, the operation of the above conventional example will be explained.
When a starter switch (not shown) is closed, the magnetic core is magnetized and the plunger is attracted to the left, and the upper end 38b of the shift lever is inserted into the hole 42 of the holder 41 integrated with the plunger.
also moves to the left against the Torsion spring.

Therefore, the lower end 38c of the shift lever 38 pushes the pinion shaft 25 to the right against the pinion shaft return spring 26, and the pinion 29 meshes with the ring gear 45 of the engine. Note that when the starter switch is closed, the motor 2
A small current also flows through the armature 10, and by the action of the helical spline 30, the pinion 29 is pushed to the right while rotating slowly, so that it can mesh smoothly with the ring gear 45 of the engine. When the engagement between the pinion 29 and the ring gear 45 is completed, the main switch is closed and the motor 2 is directly connected to the battery.
A strong rotational force is generated, and the rotational force is transmitted to the engine through the following path. Armature 10 → Armature shaft 11 → Armature gear 12 → Clutch gear 23 →
Clutch out 15 → roller 16 → clutch inner 17
→Helical spline 30→Pinion shaft 25→Pinion 29→Ring gear 45 If the starter switch is still closed after the engine has started, the one-way clutch 4 will operate and only the clutch inner 17 will idle, and the motor 2 will be driven from the engine side in the opposite direction. This prevents the

When the starter switch is opened, the energization to the magnet coil 7 is stopped, so that the plunger returns to its original position by the action of the torsion spring 39 and becomes ready for restarting.
l Next, the operation of the conventional pinion shaft 25 will be explained in detail.

When the end surface 25a on the opposite pinion side of the pinion shaft 25 is pushed by the lower end 38C of the shift lever 38, the pinion shaft 25 moves forward to the right against the spring force of the pinion shaft return spring 26 and engages with the ring gear 45'' as shown in FIG. As shown in FIG. 2, the clutch remains stationary with a small gap G left between the stopper 27 and the opposite end surface 17a of the clutch inner 17.

The reason why the gap G is maintained is to ensure sufficient contact between the main switch contacts even if they wear out. Here, when the rotational force from the armature 10 is transmitted to drive the engine, the pinion shaft 25 moves to the right by the action of the helical spline 30 connecting the clutch inner 17 and the pinion shaft 25, and the gap G=0. Become. If the starter switch is still closed after the engine has started, the one-way clutch 4 will work.
The engagement between the clutch inner 17 and the clutch outer is released.

During this overrun, a thrust force is generated between the helical spline 30 connecting the clutch inner 17 and the pinion shaft 25 in the direction in which the pinion shaft 25 returns, that is, to the left in FIG. It will retreat to the state and rotate. Therefore, since the pinion shaft return spring 26 rotates at high speed, it is enlarged to fit into the gap G due to the action of centrifugal force, and has the disadvantage that it is eventually scattered and destroyed. An object of the present invention is to eliminate the drawbacks of the prior art, and to prevent the pinion shaft return spring 26 from overrunning the pinion.
To provide a pinion transmission device for a starter that does not scatter.

In the starter pinion transmission device according to the present invention, the pinion shaft 25 is supported by the helical spline large diameter portion of the clutch inner and the inner circumference small diameter portion 17d at the rear end, and the stopper 27 that restricts the movement of the pinion at the time of pinion overrun is installed in the clutch inner. The pinion shaft return spring 26 is completely housed in the inner peripheral portion 17b to prevent the pinion shaft return spring 26 from flying off and being destroyed, and at the same time, to shorten the overall length of the starter.

Embodiments of the present invention will be described based on the accompanying drawings.

3 and 5 show embodiments of the present invention. That is, the right journal 32 provided between the pinion 29 and the helical spline 30 in the conventional pinion shaft 25
Since the pinion shaft 25 is supported by the large diameter portion of the helical spline 30 and the left journal 31, the left journal 31 can be brought closer to the pinion 29 side. Therefore, the bearing portion 17d of the clutch inner 17, which is the left bearing portion of the pinion shaft 25, has also moved significantly closer to the pinion 29 side. Therefore, a pinion shaft return spring 26 is disposed between the outer periphery of the pinion shaft 25 and the stopper 27, and
The stopper 27 is configured such that the protrusion movement of the pinion shaft 11 is restricted by the collision between the stopper 7c and the end 27a of the stopper.
was fixed to the pinion-on-shaft 25 with a clip 28.

As a result, as shown in FIG. 5, even in the event of overrun, the pinion shaft return spring 26 remains
It is completely housed in the inner peripheral part 17b on the opposite pinion side. Further, in order to prevent the pinion shaft 25 from collapsing, in the present invention, the helical spline 30 has a large diameter, and the pinion shaft 25 is supported at two points: the helical spline 30 and the inner peripheral portion 17d of the clutch inner 17. By implementing the present invention, it is possible to completely incorporate the stopper and pinion shaft return spring into the clutch inner,
It is possible to provide a starter pinion transmission device in which the overall length of the pinion transmission device is significantly shortened and the pinion shaft return spring is not damaged even during overrun.

[Brief explanation of drawings]

Figure 1 is a partial sectional view of a starter using a conventional pinion transmission, Figure 2 is a sectional view of a conventional pinion transmission,
FIG. 3 is a sectional view of the pinion transmission device of the present invention, FIG. 4 is a sectional view of the conventional pinion transmission device when the pinion pops out, and FIG. 5 shows the pinion transmission device of the present invention when the pinion pops out. FIG. 10... Armature, 15... Clutch outer, 17... Clutch inner, 17c
・・・・・・Clutch inner opposite pinion side inner diameter stepped part, 1
7b...Clutch inner anti-pinion side inner diameter part,
23...Clutch gear, 25...Pinion shaft, 26...Pinion shaft return spring, 27...Stopper, 27a...Stopper end, 29. ...Zenion, 30...Helical spline, 31...Pinion shaft left ginal.

Claims (1)

[Claims] 1. A pinion shaft having an engine drive pinion, a clutch inner screwed with the pinion shaft by a helical spline, and a clutch outer positioned on the outer periphery of the clutch inner via a roller and engaged with the clutch inner only in one direction. A clutch gear formed on the outer periphery of the clutch outer and transmitting the rotational torque of the armature, a stopper disposed on the outer periphery of the pinion shaft on the side opposite to the pinion, and a pinion shaft return spring disposed on the inner diameter stepped portion of the clutch inner on the side opposite to the pinion. In the starter pinion transmission device, the pinion shaft return spring is housed in the inner periphery of the clutch inner on the side opposite to the pinion when the pinion is ejected, and the pinion stopper and the clutch inner are in contact with each other when the pinion shaft is at maximum movement. A starter pinion transmission device featuring: