JPS60184964A - Reduction starter - Google Patents

Abstract

PURPOSE:To enable effective absorption of partial contact in gear meshing housing a fixed sun gear in the free state inside a space defined between a rotary- side center bracket and a pinion-side center bracket which support a rotary shaft. CONSTITUTION:In the titled stator, the output power of the rotary 2 of a motor 1 is transmitted to a plurality of planetary gears 7 in mesh with a fixed sun gear 6 from a rotary sun gear integrated with a rotary shaft 3. The planetary gears 7 make orbital turn to revolve a pinion shaft 10 via a planetary arm 9. The revolution thereof is transmitted via a roller clutch 11 to a pinion 12, cranking an engine. The external peripheral wall of a rotary-side center bracket 14 is bent in the shape of L and the bent tip is brought into contact with the side face of a pinion-side center bracket 18. The fixed sun gear 6 is housed in the space defined between those brackets and the internal gear 25 is made in engagement with a teeth part 27 projecting on the side face of the bracket 18.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a beam induction starter. In particular, the invention relates to a duction starter that is equipped with a planetary gear reduction device that reduces rotational force and transmits it to a pinion. This type of starter is used, for example, as a reduction starter for starting an engine, which is used to reduce the rotational force of an electric motor.

[Background of the invention]

Conventional traction starters of this type have the problem that the gears are in uneven contact, resulting in unstable strength. Such uneven contact in gear meshing is caused by accuracy errors between each part. Furthermore, in a reduction starter having a plurality of planetary gears, irregularities in the mounting dimensions are also a major cause. However, in the prior art, it has been difficult to completely prevent such uneven contact.

The problems of the prior art will be explained below with reference to the drawings.

Figure 5 shows a general conventional example in which a planetary gear meshes with a rotating sun gear a formed on a shaft, and this planetary gear meshes with a fixed sun gear C. A conventional example is shown in which a sun gear is integrated with an intermediate bracket to form a ring gear assembly d (see Japanese Utility Model Application Publication No. 58-67977).

In the conventional example shown in Fig. 6, the fixed sun gear (internal gear) is integrally formed with the intermediate bracket, which is a structural body, to form a ring gear assembly d, so the fixed sun gear is completely fixed in position. There is.

In the conventional example shown in Fig. 5, the fixed sun gear a is also connected to the intermediate bracket e.
It must be fixed with a bottle, screw, etc., or fixedly attached to another structure, and it also requires mechanical fixation. Therefore, if there is even a slight deviation in the mounting dimensions of the planetary gear, the fixed sun gear a (or the ring gear assembly d integrated with the bracket) cannot be deformed to absorb this deviation, resulting in uneven contact.

It is also possible to consider a structure in which the internal gear member is placed on the intermediate bracket via an elastic body (for example, a leaf spring or rubber) to prevent one-sided contact, but in this case, a large transmission force is required for engine starting, etc. In the case of the elastic body, the structure of the elastic body is complicated and the shape is large. In addition, when such an elastic body is used, the elastic body changes over time, and eventually the strength of Σ becomes unstable.

The above r・1 <In the conventional technology, the strength is unstable due to uneven contact due to misalignment, and extreme stress is generated in the part where uneven contact occurs, so the material of the fixed sun gear As a result, we had no choice but to use materials with high strength such as steel. A structure using an elastic body becomes complicated and large-sized, and strength instability cannot be resolved, so it is not a fundamental solution.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a planetary gear speed reduction device or a duction starter in which the gears do not come into partial contact when the planetary gears and the fixed sun gear mesh with each other. Furthermore, in this case, the power to be transmitted is evenly distributed to multiple planetary gears to stabilize the gear strength, thereby preventing the occurrence of extreme stress due to uneven force application, and as a result, the gears are fixed. The purpose is to make it possible to use not only conventional steel but also resin and other materials for the sun gear.

[Summary of the invention]

The glue reduction starter of the present invention can be obtained by bending the outer periphery of the rotor-side center bracket that supports the rotating shaft into an abbreviated shape, and abutting the bent end against the side surface of the pinion-side center bracket that supports the pinion. The fixed sun gear is inserted into the space with a slight side gap, and the internal gear of the fixed sun gear is fitted into the toothed part protruding from one side of the center bracket on the pinion side, while each center bracket is fixed. It is equipped with a planetary gear reduction device that is fixed to the gear case by inserting bolts into it. In this way, the fixed sun gear of the present invention has a gap and is installed by fitting, so it can be stored in a relatively free state. Therefore, even if there is misalignment due to dimensional errors or other reasons, the fixed sun gear can be fixed. This is absorbed by the elastic deformation, so that no uneven contact occurs. And if the fixed sun gear is fixed to a bracket etc.,
Since elastic deformation still occurs using the fixed part as a fulcrum, there is a high possibility that uneven force will be applied to the fixed sun gear and extreme stress will occur, but in the present invention, the fixed sun gear is fixed to a bracket or the like. Since it is not symmetrical, it can be elastically deformed uniformly, and uneven contact can be prevented with stable operation. It is no longer necessary to use a material with high strength for the fixed sun gear.

[Embodiment of the Invention] An embodiment of the present invention will be described below. In this embodiment, the present invention is applied to a starter that decelerates the rotation of an armature 2 of an electric motor 1 and transmits it to a pinion 12, thereby starting an engine.

In FIG. 1, the output of an armature 2 of an electric motor 1 is transmitted from an armature pinion (rotating sun gear) 4 formed on an armature shaft 3 to an internal gear (fixed A plurality of planetary gears 7 are meshed with the sun gear) 6 and each gear of the armature chabinion 4 and are arranged at approximately equally divided positions on the circumference.
transmitted to.

The power transmitted to the planetary gear 7 is then transmitted to the planetary arm 9, which has a support pin 8 that rotatably supports the planetary gear 7 and rotates as the planetary arm 9 revolves, and a pinion shaft 10 formed integrally with the planetary arm 9. transmitted to. Thereafter, the signal is transmitted from the pinion shaft 10 to the roller clutch 11 and the pinion 12 to crank the engine.

The armature shaft 3 is provided in the rear cupney 13 and the armature side center bracket 14, respectively, and has a 7'C bearing 1.
5.16, and the pinion shaft 10 is supported by bearings 19.20 provided in the gear case 17 and the pinion side center bracket 18, respectively. Fixing bolt 2
1 connects the yoke 22 and the rear cover 13 to the gear case 17
It is for fixing to.

The armature side center bracket 14 has an outer circumference of L
It is constructed by folding it into a letter shape. Furthermore, the fixed sun gear 4 is inserted into the space obtained by abutting the bent tip against the side surface of the pinion side center bracket 18, with a slight side gap left.

Specifically, in this embodiment, the armature-side center bracket 14 is formed of an iron plate or the like, and is structured into a two-stage structure having a first cylindrical portion 23 that accommodates the bearing 16 and a second cylindrical portion 24 that accommodates the internal gear 6. It is made into a 1L-shape by press-molding it into an L-shape.

In addition, the depth H and inner diameter of this second cylindrical portion 24 have a slight gap (about 0.2 mm) with respect to the axial dimension and outer cylindrical diameter d of the internal gear 6 to be stored in this portion. It is designed to last.

In addition, the internal gear (fixed sun gear) 6 in this example is the second
As shown in the figure, this is formed as an annular cylinder 26 with an internal gear 25 formed on its inner periphery. This internal gear 26
can be formed from metal such as steel or aluminum, or from resin by cold open molding or resin molding.

As will be described later, it is not necessarily made of steel, but may be made of resin. As in this example, the fixed sun gear 6 can be formed in a symmetrical shape, so it is easy to manufacture, and since it can be assembled from either side, it is easy to assemble, and since position detection is not required, it can be assembled automatically.

As shown in Fig. 3, the pinion side center bracket 18
has a protruding tooth-shaped portion 27 formed on its negative side. The internal gear 25 (FIG. 2) of the fixed sun gear 6 is fitted into this toothed portion 27.

In this example, the details are as follows. That is, as shown in FIG. 3, the pinion side center bracket 18 of this example has
- Cold-open molding or precision casting into a shape with tooth profiles 27 protruding from the sides. The tooth profile 27 is designed to have the same number of teeth so that it can be inserted into the internal gear 25 of the internal gear through an optimal gap (backlash of approximately 0.1 module), and the rim 2B of the tooth profile 27 is designed to have the same number of teeth. 1st inside
The planetary arm 9 explained in the figure can be stored. The bearing 20 is press-fitted into the center. The hole 29 is for inserting the fixing bolt 21 and fixing the pinion side center bracket to prevent it from idling.

As described above, the pinion-side center bracket 18 and the fixed sun gear 6 are not separate bodies, and both are fixedly attached, but the internal gear 25 of the fixed sun gear 6 is fitted into the toothed part 27 of the bracket 18. The structure is such that it can be installed by As a result, the fixed sun gear 6 can be elastically deformed to a certain degree. Moreover, this elastic deformation is performed uniformly because a part of the fixed sun gear 6 is not fixed to any part.

The effect of preventing uneven contact due to this will be described next.

That is, it will be explained in detail below that the planetary gear reduction device configured as described above can effectively prevent the one-sided contact of the gear, which is the object of the present invention.

As mentioned above, uneven contact in gear meshing is largely due to accuracy errors between each part, but in products with multiple planetary gears such as this reduction starter, irregularities in the mounting dimensions are also a major cause. occupies .

If one of the planetary gears 7 has a large irregularity in the installation dimensions, the fixed sun gear 6 will be placed in the annular space 5 created by each center bracket 14, 18, as described above, by attaching the pinion side center bracket 18. Since the tooth profile 27 and the internal gear 25 of the fixed sun gear 6 are inserted and assembled in a relatively free state, the fixed sun gear 6 easily eccentricizes in response to the revolution of the planetary gear 7, causing the planetary gear to become eccentric. The power of the gears 7 is equally distributed.

If there is a large installation irregularity, the power cannot be distributed evenly just by the effect of the eccentricity of the fixed sun gear 6, but in this case, it is due to the elastic deformation of the fixed sun gear 6.

In this case, according to the present structure, since the annular tube 26 of the fixed sun gear 6 has a uniform cross-sectional shape as shown in FIG. 4, its elastic deformation is uniformly distributed as shown by the broken line 34. As a result, the internal stress generated in the fixed sun gear 6 is also distributed over the whole and becomes small. Therefore, no extreme stress or excessive force is applied to the fixed sun gear 6, and it is therefore possible to form it not only from a strong material such as steel but also from resin or the like. .

Moreover, this allows uneven contact of the gears to be effectively absorbed, and the plurality of planetary gears 7 accurately distributes the transmitted power evenly.

If you fixed the sun gear 6 like this, the center bracket 1
For example, one end of the fixed sun gear 6 (the right end in the figure) of the fixed sun gear 6 in FIG.
8, the restraint point becomes a fulcrum, and the part at this fulcrum does not deform, and the parts away from it deform sequentially, and the elastic deformation becomes uniform. It will be missing. This prevents the occurrence of extreme stress,
Precise prevention of uneven contact and equal distribution of transmitted power between multiple planetary gears cannot be fully expected. Therefore, this configuration can be said to have solved this problem.

〔Effect of the invention〕

As mentioned above, the glue reduction starter of the present invention has various effects as listed below.

(1) Since the fixed sun gear is not restrained by the center bracket and is housed in a free state, uneven contact of the gear can be effectively absorbed. Therefore, it is highly durable and has a long lifespan. The noise during operation can also be reduced. Of course, it also has the effect of stable operation. In addition, the plurality of planetary gears accurately distribute the transmitted power evenly, which further ensures the stability of operation.

(2) The elastic deformation of the fixed sun gear is uniform and distributed over almost the entire gear, resulting in less internal stress and stable strength.

(3) As a result of the above (11 (21), there is a margin in the gear strength, so it is not necessary to use a fixed sun gear with high strength. For example, it is possible to use resin as the material, which makes it easier to select the material. Greater freedom.

(4) As a result of the above, lightweight materials such as resin can be used, so weight can be reduced. Even when steel or the like is used, it is easy to reduce the size and weight by making the wall thinner.

(5) There is no need for a special elastic body for absorbing uneven contact, and a simple structure can be provided with a duction starter.

As mentioned above, the practical effects of the present invention are significant.

It should be noted that, as a matter of course, the present invention is not limited to the illustrated embodiment.

[Brief explanation of drawings]

1 to 4 show a reduction starter according to an embodiment of the present invention, FIG. 1 is a partial sectional view thereof, FIG. 2 is a perspective view of its fixed sun gear, and FIG. 3 is a center view of its pinion side. A perspective view of the bracket, and FIG. 4 is a sectional view of a main part to show the function. 5 and 6 are respectively simplified diagrams of conventional examples. 3... Armature shaft (rotating shaft), 4...
・Armor cha pinion (rotating sun gear), 5... annular space, 6... internal gear (fixed sun gear), 7
... Planetary gear, 10 ... Pinion shaft, 14.
... Armature side center bracket (rotor side center bracket), 17... Gear case, 18... Pinion side center bracket, 21... Fixing bolt,
25... Inner wheel, 27... Protruding tooth profile. Agent Patent Attorney Masami Akimoto Figure 2, Figure 13, Figure 41

Claims (1)

[Claims] 1. A rotating sun gear formed on a rotating shaft, a fixed sun gear installed on this rotating sun gear via an annular space,
a plurality of planetary gears that mesh with each of the gears and are arranged at approximately equal positions on the circumference; a pinion shaft that rotatably supports the planetary gears and rotates as the planetary gears revolve; a rotating shaft; In a duction starter equipped with a planetary gear reduction device having a rotor-side center bracket and a pinion-side center bracket that respectively support a pinion shaft, the outer periphery of the rotor-side center bracket is bent and the bent tip is attached to the pinion-side center bracket. The fixed sun gear is inserted into the space obtained by abutting against the side surface of the pinion side center bracket with a slight side gap, and the internal gear of the fixed sun gear is inserted into the toothed part protruding from one side of the center bracket on the pinion side. A duction starter equipped with a planetary gear reduction device, in which each center bracket is fixed to the gear case by inserting a fixing bolt into the center bracket.