JPH0616985Y2 - Planetary deceleration type starter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a starter, in particular, one having a planetary gear speed reducer incorporated therein.

[Conventional technology]

Conventionally, as an example of the planetary gear reduction starter, there is one as shown in FIG. In FIG. 2, 1 is an armature of a direct current motor, 2 is an armature rotating shaft, 3 is a yoke of a direct current motor, and an end face of which is a front bracket 5 fitted with an internal gear 4 which constitutes a planetary gear speed reducer. Are connected. A sun gear 6 is formed at a front end portion of the armature rotating shaft 2, and a planetary gear 7 is meshed with the sun gear 6, and the planetary gear 7 is attached to a support pin 9 via a bearing 8 fitted on an inner peripheral surface thereof. It is supported. Reference numeral 10 is a flange for fixing the support pin 9, which constitutes an arm of the planetary gear speed reducer, and an output rotary shaft 11 is integrally formed with the arm. Reference numeral 12 is a sleeve bearing fitted to the inner peripheral surface of the projection 41 of the internal gear 4, and supports the output rotary shaft 11. Reference numeral 13 denotes a sleeve bearing fitted in a recess in the rear inner peripheral surface of the output rotary shaft 11, and supports the front end of the armature rotary shaft 2. Reference numeral 14 is a steel ball fitted between the ends of the armature rotary shaft 2 and the output rotary shaft 11 and has a function of transmitting and receiving a thrust load. Reference numeral 15 is a permanent magnet that generates a field, and 31 is a radial flange portion formed by bending the end portion of the yoke 3 inward, which serves to maintain the thrust direction of the planetary gears, the reduction portion and the motor portion. This is for shielding each other from dust.

Next, the operation will be described. By closing a key switch (not shown), the armature 1 is energized and energized, and a rotational force is generated under the magnetic energization of the permanent magnet 15. The rotating force of the armature 1 is transmitted to the planetary gear 7 via the sun gear 6 of the rotating shaft 2, the rotating speed is reduced, and the flange portion
It is transmitted to the output rotary shaft 11 via 10. Further, the rotational force of the output rotary shaft 11 is transmitted to a ring gear of an internal combustion engine (not shown) via a pinion of an overrunning clutch (not shown) fitted to the output rotary shaft 11.

[Problems to be solved by the invention]

As described above, the conventional device is provided with the internal gear that constitutes the planetary gear speed reducer as a separate body, so that the number of parts is increased, the structure is complicated, and the assembling is problematic.

The present invention has been made to solve the above problems, and an object thereof is to reduce the number of parts and to obtain a starter excellent in assemblability.

[Means for solving problems]

The planetary reduction type starter according to the present invention integrally forms an internal gear that constitutes the planetary gear mechanism at the tip of the yoke, and rotates the armature on the inner surface of the middle of the yoke (between the motor part and the internal gear). A flange portion in which a bearing for supporting the shaft is fitted is integrally formed.

[Action]

In this invention, since the yoke and the internal gear in the conventional starter and the flange portion that supports the armature rotating shaft are integrally formed, the separate internal gear and the center bracket are unnecessary, and The points are reduced.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is an armature of a DC motor, 2 is an armature rotating shaft, 3 is a yoke of a DC motor, an internal gear 4 is formed at its tip, and a radial flange portion is provided at an intermediate portion. 3b
Is integrally formed on the inner surface of the annular yoke portion 3a, and the bearing 16 is fitted on the inner peripheral portion of the flange portion 3b. The bearing 16 supports the armature rotating shaft 2. A sun gear 6 is formed at a front end portion of the armature rotating shaft 2, and the sun gear 6 is formed on the sun gear 6.
The planetary gear 7 that meshes with is meshed. Since the other configurations and operations are almost the same as those in FIG.

In the above embodiment, the permanent magnet is used to generate the field of the electric motor, but the same effect can be obtained even if the magnetic pole iron core is wound with a coil.

In addition, as for the integral molding of the yoke, any manufacturing method for forming the low carbon steel, such as cold forging, sintering, sintering forging, and injection molding powder metallurgy, may be used. In addition, the yoke portion to which the permanent magnet is attached may be formed by ironing the inner or outer diameter or the inner or outer diameter after the above formation.

[Effect of device]

As described above, according to the present invention, the yoke, the internal gear that constitutes the planetary gear speed reducer, and the bearing that supports the armature rotating shaft are fitted and the flange that holds the planetary gear in the thrust direction is integrally formed. With this configuration, the number of parts is reduced, the structure of the reduction mechanism is simplified, and the flange that holds the internal gear and bearing and that holds the planetary gear in the thrust direction is formed during the yoke manufacturing process. Since they are obtained at one time, the number of processing steps can be reduced and the assembling can be facilitated, and there is an effect of greatly contributing to the cost reduction of the device.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional planetary reduction type starter. In the figure, 2 is an armature rotating shaft, 3 is a yoke, 3a is a motor part of the yoke, 3b is a flange part, 4 is an internal gear, 5 is a front bracket, and 16 is a bearing. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. A starter having a planetary gear reducer built-in, wherein an internal gear of the planetary gear reducer is formed on the inner periphery of the front end of an annular yoke of an electric motor directly connected to a front bracket, and an intermediate portion of the yoke. A planetary reduction type starter characterized in that a radial flange is formed integrally with the yoke on the inner surface, and a bearing fitted to the inner periphery of the flange supports the armature rotating shaft.