JP3186176B2 - Reduction type starter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deceleration type starter.
Specifically, the present invention relates to the shock absorbing mechanism.

[0002]

2. Description of the Related Art Japanese Utility Model Publication No. Sho 60-9415 discloses that a first gear meshing with an armature gear and a second gear meshing with a clutch outer gear are coaxially arranged adjacent to each other in the axial direction.
The two gears are brought into end face contact, and the frictional force at the end face contact portion is strengthened by a spring, torque is transmitted between the two gears by this frictional force, and when an impact load is generated between the ring gear and the pinion gear, the two gears are brought into contact with each other. Is slid on the end face to absorb the impact load.

[0003]

However, the above-described shock absorbing mechanism has the following problems. First, abrasion of the friction end surface generates abraded metal powder, which invades each bearing portion and causes abrasion, and the abrasion of the end surface causes the spring to loosen and the slip start torque of the friction end surface to fluctuate.

Second, since the base end of the spring is locked by the stationary housing, and the tip end of the spring is locked by the rotating first gear, the tip of the spring and the locking end face of the first gear are worn. However, the spring is displaced in the rotation direction due to the rotation of the first gear. Third, it is necessary to increase the size of the entire device in the axial direction by the spring accommodating space.

[0005] Fourth, when a lubricant such as oil or grease is mixed into a friction end face rather than a bearing or a gear face, a slip start torque greatly varies. In particular, since the first gear is rotatably fitted to the shaft cylinder portion extending in the axial direction from the second gear, it is difficult to prevent the lubricant from entering the friction end face in consideration of lubrication of this portion. . SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a deceleration-type starter that constantly exhibits a stable shock absorbing ability and can prevent an increase in device space.

[0006]

SUMMARY OF THE INVENTION A reduction starter according to the present invention is provided with a clutch outer gear formed on an outer peripheral surface of a clutch outer of a one-way clutch for transmitting torque to a pinion gear for driving a ring gear, and an armature. A rotating armature gear; and an idle gear rotatably fitted to a pin supported by the housing and meshing with the armature gear and the clutch outer gear to transmit torque of the armature gear to the clutch outer gear. The idler gear includes a first gear rotatably fitted to the pin, the first gear having a gear portion meshing with the armature gear on the outer peripheral surface, and the clutch outer gear on the outer peripheral surface. A second gear having a gear portion to be meshed and rotatably fitted to the pin adjacent to the first gear; At least one of the first gear and the second gear is accommodated in a central concave portion formed at a radial central portion, and a radial outer end portion is locked on an inner peripheral surface defining the central concave portion, and a gap between the two gears is formed. And an elastic member that elastically couples.

In a preferred aspect, a roller is provided adjacent to the elastic member along the periphery of the pin, and the roller connects the two gears via the elastic member. At least one of the inner peripheral surface of the two gears and the outer peripheral surface of the pin are in contact with each other.

[0008]

The driving torque of the armature is changed from the armature gear to the first gear, an elastic member between the first gear and the second gear,
The power is transmitted to the pinion gear via the second gear and the clutch outer gear, and the engine is started from the pinion gear via the ring gear. If the engine suddenly stops immediately after the engine is ignited, for example, the one-way clutch will be in a locked state, so a large impact torque will act on the reduction mechanism consisting of the first gear, the second gear, and the armature gear, which are high-speed rotating parts. The impact torque is absorbed by the elastic member, and each gear is protected from the impact torque.

[0009]

As described above, in the reduction type starter of the present invention, the idle gear is constituted by the first and second gears coaxially and axially adjacent to each other and the elastic member elastically connecting these two gears. Therefore, the gears can be prevented from being broken by absorbing the impact by the elastic member. Further, as compared with the case where the two gears are friction-coupled to each other, it is possible to avoid the above-described problem due to wear.

Further, since the elastic member is accommodated in at least one of the two gears, the idle gear and the housing for accommodating the idle gear are not increased in size, and an increase in physique weight can be suppressed.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) An embodiment of the present invention will be described with reference to FIGS. The starter includes a front case 15 disposed on the pinion gear side (front side) and a center case 13 fastened to the rear side of the front case 15, and an internal space between the two cases 15, 13 will be described later. A gear space for accommodating the reduction gear mechanism and the one-way clutch.

A motor housing hole and a magnet switch housing hole are opened on the rear side of the center case 13. The starter motor 8 is housed in the former, and the magnet switch 9 is housed in the latter. The starter motor 8 includes a cylindrical yoke 40, and a bowl-shaped end frame 14 is fitted to a rear end of the yoke 40 so as to close a rear end opening of the yoke 40. 14 is fastened to the front case 15 by a long bolt (not shown) penetrating the center case 13.

Center case 13 and end frame 1
4 supports an armature shaft 10 via bearings 11 and 12, and the armature shaft 10 has an armature 17.
Are spline-fitted. The armature shaft 1 that penetrates through the center case 13 and projects above the gear space.
The armature gear 1 is integrally formed at the front end of the clutch gear 0 with a clutch outer gear 21 of a one-way clutch B via an idle gear A which is a main part of the present embodiment. are doing. The clutch outer gear 21 is formed on the outer peripheral surface of the clutch outer 22, and the clutch outer 22 is rotatably fitted on the outer peripheral surface of the clutch inner 23 of the one-way clutch B. The clutch inner 23 is rotatably supported by the front case 15 and the center case 13 by bearings.
A clutch roller and a spring for transmitting torque in one direction from the clutch outer to the clutch inner are accommodated in the wedge-shaped space between the clutch rollers.

A drive shaft 24 penetrates through the clutch inner 23 so as to be rotatable and axially retractable.
Drive shaft 24 projecting from clutch inner 23
A pinion gear 20 is spline-fitted on the outer peripheral surface of the front end portion so as to be able to advance and retreat in the axial direction. On the other hand, a plunger (not shown) is held inside the magnet switch 9 caulked by the center case 13 so as to be able to advance and retreat in the axial direction. When the magnet switch 9 is energized, the plunger is moved via a push rod (not shown). Drive shaft 2
4 is pushed forward to engage the pinion gear 20 with a ring gear (not shown), and when the power is cut off, the plunger, push rod and drive shaft 24 are retracted to the original positions by a spring (not shown). The drive shaft 24 is helically spline-fitted to the clutch inner 23 of the one-way clutch B.
Armature gear 1, idle gear A,
The drive shaft 24 and the pinion gear 20 are rotated through the one-way clutch B, and the engine is started through a ring gear (not shown).

The main part of this embodiment will be described below. The idle gear A includes the front case 15 and the center case 1
3, a second gear 3a rotatably fitted to the pin 16, five rollers 4 extending rearward from the second gear 3a along the outer periphery of the pin 16, and each roller A first gear 3b rotatably fitted to the rear half of the fourth gear 4;
And an elastic member 6 housed inside the first gear 3b.

The second gear 3a meshes with the clutch outer gear 21 and is rotatable around the pin 16. The first gear 3b meshes with the armature gear 1 and rotates around the pin 16 via the roller 4. It is rotatable. Each roller 4 is made of a columnar steel member, and the first half of each roller 4 is pressed into a recess (not shown) of the wheel plate 5 as shown in FIG. The first half of the roller 4 and the wheel plate 5
Is inserted when the second gear 3a is sintered and integrated with the second gear 3a (see FIG. 3).

The first gear 3b is also made of an oil-impregnated sintered alloy similarly to the second gear 3a. As shown in FIG. 4, a central concave portion 39 penetrating in the axial direction is provided in the central portion in the axial direction.
The rear half of each roller 4 is fitted into the central concave portion 39, and the outer peripheral surface of the roller 4 is in contact with the inner peripheral surface of the first gear 3b and the outer peripheral surface of the pin 16 so as to be relatively rotatable. As shown in FIG. 4, elastic members 6 made of hard rubber are arranged inside the central recess 39 between the rollers 4 arranged at regular intervals around the pins 16. The elastic members 6 are adjacent to each other.
Arcuate concave side surface abutting on the roller 4 and the second gear 3a
An arc-shaped convex surface formed with a small gap on the inner peripheral surface of
An outer peripheral surface of the pin 16 has an arc-shaped concave surface formed with a minute gap therebetween.

As shown in FIG. 4, a plurality of recesses 38 are provided in the radial direction on the inner peripheral surface of the second gear 3a, and project from the arc-shaped convex surface of the elastic member 6 in the centrifugal direction. The projection 6b fits into the recess 38. Both gears 3a,
3b, the displacement in the axial direction is regulated by assembling the front case 15 to the center case 13.
Hereinafter, the operation of the idle gear A will be described.

When the armature 17 rotates, the armature gear 1 rotates the first gear 3b, and the torque of the first gear 3b is transmitted from the elastic member 6 to the roller 4, and
To the second gear 3a, and both gears 3a and 3b rotate integrally. The second gear 3a rotates the ring gear through the one-way clutch B, the drive shaft 24 and the pinion gear 20 at a reduced speed.

Here, when an excessive load is generated between the ring gear and the one-way clutch B due to sudden stop of the engine or the like, the elastic member 6 is elastically deformed in the circumferential direction, absorbs an impact, and prevents the gear from being damaged. I do. The important point in this embodiment is that, as shown in FIG. 4, each roller 4 performs the positioning of the second gear 3 a and the first gear 3 b, that is, the centering, and the position between the second gear 3 a and the elastic member 6. In the axial direction. That is, the elastic member 6 does not need to transmit torque in the axial direction between the second gear 3a and the first gear 3b, but only deforms in the circumferential direction when an impact occurs,
Thereby, only the first gear 3b is displaced in the circumferential direction with respect to the roller 4, so that only a small number of elastic members are required and the fatigue thereof is also small.

In the above embodiment, the five elastic members 6 are separately interposed between the five rollers 4, but the respective elastic members 6 can be integrated. That is, the pin 16
A concave portion into which the roller 4 is fitted may be provided in a ring-shaped elastic member fitted into the elastic member. Also, the concave portion 38 of the first gear 3b
May be used as protrusions, and the protrusion 6b of the elastic member 6 may be used as a recess. The number of these protrusions and recesses can be set arbitrarily. (Embodiment 2) Another embodiment is shown in FIG.

In this embodiment, the second gear 3a has the same structure as the first gear 3b, and the impact torque is controlled by an elastic member (not shown) from the second gear 3a to the inside of the second gear 3a.
And transmitted to the roller 4 via the first gear 3
b through the elastic member 6 inside the first gear 3b (see FIG. 4).
, And most of the elastic members are absorbed by the deformation of these elastic members. In this embodiment, the roller 4 is a second gear 3a.
The roller 4 in contact with the pin 16
Is displaced, and uneven wear of the contact surface can be avoided. (Embodiment 3) Another embodiment is shown in FIG.

In this embodiment, the roller 4 is connected to the second gear 3a.
Is provided with a hole 37 into which the roller 4 is rotatably fitted. In this way, since the roller 4 is rotatable, uneven wear of the roller 4 can be avoided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a starter according to an embodiment of the present invention;

FIG. 2 is a perspective view showing an assembled state of a roller and a wheel plate;

FIG. 3 is a perspective view of a second gear and a roller integrated therewith,

FIG. 4 is a sectional view showing an arrangement state of a first gear, an elastic member, a roller, and a pin;

FIG. 5 is an enlarged sectional view of a main part of a starter showing another embodiment;

FIG. 6 is a front view of a second gear used in another embodiment;

[Explanation of symbols]

A is an idle gear, B is a one-way clutch, 1 is an armature gear, 3b is a first gear, 3a is a second gear, 10 is an armature shaft, 13 is a center case (housing), 15 is a front case (housing), 16 is a pin, 17 is an armature, 20 is a pinion gear, 21
Is a clutch outer, and 22 is a clutch outer gear.

Claims (2)

(57) [Claims] A clutch outer gear formed on an outer peripheral surface of a clutch outer of a one-way clutch for transmitting torque to a pinion gear for driving a ring gear; an armature gear rotating integrally with the armature; and a pin supported by a housing. An idle gear that is freely fitted and that meshes with the armature gear and the clutch outer gear to transmit the torque of the armature gear to the clutch outer gear. A first gear rotatably fitted to the pin having a gear portion meshing with the armature gear on a surface thereof; and a gear portion meshing with the clutch outer gear on an outer peripheral surface, the first gear being adjacent to the first gear. A second gear rotatably fitted to the pin, and at least one of the first gear and the second gear An elastic member that is housed in a central recess formed at a radial center portion, and whose radial outer end is locked to an inner peripheral surface that defines the central recess, and that elastically couples the two gears. Deceleration type starter. 2. A roller is provided adjacent to the elastic member along the periphery of the pin, the roller connecting the two gears via the elastic member, and the outer periphery of the roller being the two gears. The deceleration-type starter according to claim 1, wherein both the inner peripheral surface and the outer peripheral surface of the pin are in contact with each other.