JPH03294657A - Inertia plunging type starter - Google Patents

Abstract

PURPOSE:To absorb impact force at the time of driving a ring gear by employing both a first elastic body furnished with a specified frictional coefficient and a second elastic body furnished with a specified frictional coefficient greater than that of the first elastic body in the axial direction between a tube and a pinion. CONSTITUTION:Torque imparted to a shaft 2 is transmitted to a tube 5, and is then transmitted to a cover 10 and a pinion 3 via a second elastic body 7 furnished with a great frictional coefficient functioning between the tube 5 and the cover 10. The pinion 3 is pushed by a first elastic body 6 as the tube 5 is advanced on the shaft 2 by means of the action of a helical line 2a, so that the pinion is meshed with a ring gear 4. In this case, advancing impact force caused by the collision of the pinion 3 against the ring gear 4 is absorbed by the first elastic body 6, and the second elastic body 7 is subjected to low load as the first elastic body 6 is deformed, so that frictional force between the tube 5 and the cover 10 thereby becomes low. As a result, impact force caused when the pinion 3 is shifted to drive the ring gear 4 is thereby absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inertial plunge starter in which a pinion moves forward and meshes with a ring gear due to the action of a helical spline.

[Prior Art] Conventionally, a starter that uses a rubber clutch has been proposed in order to absorb the impact generated between the pinion and the ring gear (see Japanese Utility Model Application Publication No. 47770/1983).
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An example of this starter is shown in FIG.

A cylindrical tube 101 is spline fitted to the outer periphery of the shirt l-100, and a stepped cylindrical clutch outer 102 is rotatably fitted.

The inner circumference of the clutch outer 102 includes the clutch outer 1
An annular elastic body 103 is disposed so as to mesh with the tube 102, and this elastic body 103 is fitted with a protrusion 101a formed on the outer periphery of the tube 101.

Therefore, due to the rotation of the shaft 100, the shaft 10
When the tube 101 spline-fitted with the clutch outer 102 rotates, the rotational force is transmitted to the clutch outer 102 via the elastic body 103, and the pinion 104 formed on the outer periphery of the clutch outer 102 rotates.

The pinion 104 is pushed by the elastic body 103 as the tube 101 moves forward on the shaft 100 due to the action of the helical spline, and meshes with the ring gear 105 .

At this time, the axial and rotational deflection of the elastic body 103 disposed between the clutch outer 102 and the tube 101 can absorb the impact that occurs when the pinion 104 and the ring gear 105 mesh with each other.

[Problem to be Solved by the Invention] However, in the starter employing the above-mentioned rubber clutch, the elastic body 103 is compressed to absorb the impact in the axial direction, but on the other hand, the elastic body 103 The more it is compressed and bent in the direction, the greater the sliding torque at the contact surface becomes. Therefore, pinion 104 and tube 10
1 means that the larger the impact torque is applied, the more difficult it becomes to rotate, and the impact absorption in the rotational direction is not performed sufficiently.

As a result, there was a problem that the pinion 104 and the shaft 100 were adversely affected. Furthermore, if the slip torque is set in accordance with a large impact torque, it becomes easy to slip during normal torque transmission, which has the disadvantage that the engine cannot be driven.

The present invention has been made based on the above circumstances, and its purpose is to provide an inertial plunge starter capable of absorbing the impact force in the rotational direction when the pinion moves at its maximum, that is, when the ring gear is driven. be.

1. Means for Solving the Problem] In order to achieve the above object, the inertial plunge starter of the present invention includes an output shaft having a helical spline formed on the outer periphery, and a tube fitted with the spline to the output shaft. , a pinion that is rotatably fitted to the output shaft at the tip side of the tube and meshes with the ring gear of the engine;
A cover is provided to rotate together with the pinion and is rotatably disposed on the rear end side of the tube with respect to the output shaft, and between the tube and the pinion in the axial direction. a first elastic body disposed between the tube and the cover and having a predetermined coefficient of friction between the tube and the pinion; The technical means is that a second elastic body having a friction coefficient larger than the predetermined friction coefficient is provided between the two elastic bodies.

[Action Co. The present invention having the above configuration has the following effects.

The rotational force generated on the output shaft is transmitted to a tube spline-fitted to the output shaft, and further transmitted via the second elastic body to the cover and a pinion that rotates together with the cover.

The pinion is pushed by the first elastic body as the tube moves forward on the output shaft due to the action of the helical spline, and meshes with the ring gear.

Here, the forward impact force generated when the pinion collides with the ring gear and when the pinion reaches the maximum movement position is absorbed by the bending of the first elastic body.

On the other hand, the load on the second elastic body becomes lower due to the bending of the first elastic body, and the frictional force between the tube and the cover becomes smaller than the initial setting value.

As a result, the pinion and the tube can easily rotate, so that the impact force in the rotational direction when the pinion shifts to driving the ring gear is absorbed.

[Effects of the Invention] In the inertial plunge starter of the present invention having the above-mentioned effect, the greater the forward impact force, the greater the deflection of the first elastic body, and the smaller the load on the second elastic body. In other words, it becomes easy to slip between the second elastic body and the tube and cover. Therefore, at the time of maximum movement of the pinion when the forward impact force is maximum,
It is possible to absorb and alleviate the impact force in the rotational direction that occurs when driving the ring gear, and it is possible to prevent adverse effects on the pinion and output shaft.

In addition, during normal torque transmission, the rotational force of the output shaft transmitted to the tube is transmitted to the pinion via the second elastic body, which has a larger coefficient of friction than the first elastic body, so that the engine can be reliably driven. Can be done.

[Example] Next, an inertial plunge starter of the present invention will be described based on an example shown in the drawings.

FIG. 1 is a sectional view of an inertial plunge starter (hereinafter abbreviated as starter).

The starter 1 of this embodiment transmits the rotational force applied to the shaft (output shaft) 2 from a motor (not shown) to the pinion 3, and also absorbs the impact force generated when the pinion 3 and the ring gear 4 mesh with each other. It has a friction clutch mechanism.

This friction clutch mechanism consists of a tube 5 that is spline-fitted to a helical spline 2a formed on the outer periphery of a shaft 2, and a distal end side of the tube 5 in the axial direction (left side in FIG. 1).
A first elastic body 6 and a second elastic body 7 are disposed on the rear end side of the first elastic body 6 and the second elastic body 7 is rotatably fitted to the shaft 2 via a bearing 8 on the distal end side of the first elastic body 6. clutch outer 9
and a cover 10 rotatably disposed on the rear end side of the second elastic body 7 with respect to the shaft 2.

The tube 5 has a cylindrical portion 5b in which a tube spline 5a that fits with the helical spline 2a of the shaft 2 is formed on the inner peripheral surface, and a large diameter portion 5c formed in a disk shape on the outer periphery of the cylindrical portion 5b. .

The first elastic body 6 and the second elastic body 7 each have an annular shape, and are fitted into a stepped portion between the cylindrical portion 5b and the large diameter portion 5C of the tube 5. The first elastic body 6 has its rear end surface (right side in FIG. 1) in contact with the tip surface of the large diameter portion 5C, and the second elastic body 7 has its tip surface in contact with the large diameter portion 5C. It is disposed in contact with the rear end surface of 5c.

The clutch outer 9 has a pinion 3 integrally formed on its outer periphery, and a tube 5 on the rear end side of the pinion 3.
A flat plate portion 9a having a slightly larger outer diameter than the large diameter portion 5C is provided. This clutch outer 9 has a flat plate portion 9a.
The rear end surface of the elastic body 6 is disposed in contact with the front end surface of the first elastic body 6. Note that the clutch outer 9 is biased rearward by a return spring 11 for returning the pinion 3.

The cover 10 is cup-shaped and includes a disk-shaped flat part 10a around the outer periphery of the shaft 2, and a cylindrical part 10b extending from the outer peripheral edge of the flat part 10a toward the distal end of the shaft 2. This cover 10 includes a duplex 5, a first elastic body 6,
The outer periphery of the clutch outer 9 is caulked with the tip of the cylindrical portion 10b so as to wrap around the second elastic body 7, and is provided to rotate together with the clutch outer 9. The cover 10 is disposed such that the front end surface of the flat portion 10a is in contact with the rear end surface of the second elastic body 7.

A stopper 12 for regulating the forward movement of the pinion 3 is fitted onto the tip of the shaft 2, and the stopper 12 is
It is locked by a snap ring 13 fitted into a circumferential groove 2b formed on the outer periphery of the shaft 2. The return spring 11 described above is fitted onto the outer periphery of the shaft 2 and is disposed between the stopper 12 and the clutch outer 9.

In this friction clutch mechanism, the first elastic body 6, the large diameter portion 5C of the tube 5, and the flat plate portion 9a of the clutch outer 9
The coefficient of friction at each contact surface with the contact surface is set to a relatively small predetermined value.

Further, the coefficient of friction at each contact surface between the second elastic body 7, the large diameter portion 5C of the duplex 5, and the flat portion 10a of the cover 10 is set to be larger than the above-mentioned predetermined value.

Next, the operation of this embodiment will be explained.

When the starter switch (not shown) is closed, the rotational force applied to the shaft 2 by the rotation of the motor is transferred to the shaft 2.
It is transmitted to the tube 5 spline-fitted to the tube 5, and further,
It is transmitted to the cover 10 and the pinion 3 that rotates together with the cover 10 via the second elastic body 7 which has a large coefficient of friction between the tube 5 and the cover 10 .

The duplex 5 to which the rotational force of the shaft 2 is transmitted moves forward on the shaft 2 by the action of the helical spline.

As a result, the pinion 3 moves forward while rotating via the first elastic body 6 and the second elastic body 7, and the ring gear 4
comes into contact with the end face of the At this time, an axial impact is applied, but the impact force is absorbed by the first elastic body 6 being compressed and bent in the axial direction.

Further, the pinion 3 is rotated and pushed in the axial direction by the end surface of the ring gear 4, thereby meshing with the ring gear 4 and moving forward until it comes into contact with the end surface of the stopper 12. At this time, an axial impact is also generated, but the first elastic body 6 bends and absorbs the impact, as in the above case.

Since the first elastic body 6 is compressed and bent in the axial direction, the load in the axial direction is reduced, so that the large diameter portion 5C of the tube 5 and the flat portion 10a of the cover 10
The pressing force applied to each contact surface with the the result,
The frictional force on each of the contact surfaces becomes smaller than the initially set slip torque, and the pinion 3 (cover 10) and tube 5 rotate more easily, so the rotation direction that occurs when moving to drive the ring gear 4 impact can be absorbed, and an adverse effect on the pinion 3 and shaft 2 can be prevented.

Further, during normal torque transmission, the rotational force of the shaft 2 transmitted to the tube 5 is transmitted to the pinion 3 via the second elastic body 7 having a larger coefficient of friction than the first elastic body 6, so that the rotational force of the shaft 2 is reliably transmitted to the engine. can be driven.

In this embodiment, an example is shown in which the clutch outer 9 is caulked with the cover 10, but the clutch outer 9 and the cover 10 are
You may fix it with a circlip (retaining ring) or the like. Alternatively, if strength permits, the clutch outer 9 and the cover 10 may be fixed by press fitting.

Moreover, the cover 10 is formed into a cup shape, and the tube 5,
Although the first elastic body 6 and the second elastic body 7 are provided so as to be wrapped therein, the clutch outer 9 may be formed into a cup shape, and the cover 10 may be formed into a disk shape with only the flat portion 10a.

[Brief explanation of drawings]

FIG. 1 shows one embodiment of the present invention, and is a sectional view of an inertial plunge starter. FIG. 2 is a sectional view of an inertial plunge starter according to the prior art. In the figure: 1... Inertial diving starter 2... Shaft (output shaft) 3... Pinion 4... Ring gear 5... Tube 6... First elastic body 7... Second Elastic body 10...cover

Claims (1)

[Scope of Claims] 1) (a) an output shaft having a helical spline formed on its outer periphery; (b) a tube spline-fitted to the output shaft; and (c) the output on the distal end side of the tube. a pinion rotatably fitted to the shaft and meshing with the ring gear of the engine; (d) provided to rotate integrally with the pinion;
(e) a cover disposed rotatably with respect to the output shaft on the rear end side of the tube; (e) a cover disposed between the tube and the pinion in the axial direction; (f) a first elastic body having a predetermined coefficient of friction between the first elastic body and the second elastic body; and a second elastic body having a coefficient of friction greater than the coefficient of friction.