JPS6332367Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an internal reduction type starter, particularly a starter incorporating a planetary gear reduction device.

Conventionally, there has been a device of this type as shown in FIG. In the figure, 1 is a starter assembly, 2 is a DC motor, 3 is a bracket to which this DC motor is attached, and 4 is a ring gear constituting a planetary gear mechanism.
Then, together with the intermediate bracket 5, the DC motor 2
It is clamped and fixed. Reference numeral 6 denotes an armature constituting the DC motor 2, the output rotating shaft 7 of which is supported by a sleeve bearing 8 fitted on the inner peripheral surface of the intermediate bracket 5, and a spur gear (sun gear) attached to the protruding end. )9 is formed. A planetary gear 10 is supported by a pin 12 attached to a flange 13 via a bearing 11, and meshes with the ring gear 4 and spur gear 9 to reduce the rotational speed of the spur gear 9 and rotate the flange. 13. Reference numeral 14 denotes an output rotating shaft that is fitted into the flange 13, and a sleeve bearing 16 is fitted into a recess 15 provided on the inner peripheral surface of the end, supporting the front end of the output rotating shaft 7. . Reference numeral 17 designates an overrunning clutch that is spline engaged with the output rotating shaft 14, and 18 designates a shift lever.

Next, the operation of the above configuration will be explained. The overrunning clutch 17 is moved forward and forced into engagement with an engine (not shown) by the shifting force of the shift lever 18. Next, the armature 6 is energized to generate rotational force, and the spur gear 9 at the front end of the rotating shaft 7 moves the planetary gear 10 into the ring gear 4.
The rotating force is transmitted to the flange 13 via the pin 12, and the output rotating shaft 14 is rotated at a reduced speed. Then, the overrunning clutch 17 spline-engaged with the output rotating shaft 14 is urged to rotate, and the internal combustion engine (not shown) is started. Incidentally, at this time, a rotational biasing reaction force is generated in the ring gear 4, but the reaction force is received by the frictional force that is engaged with the spigot part 3a.

In the conventional device as described above, the intermediate bracket that supports the input/output rotating shaft and the ring gear that constitutes the planetary gear reduction mechanism are separate structures, which increases the number of parts of the device and makes it complicated and expensive. There were some drawbacks such as.

This idea was made in order to eliminate the drawbacks of the conventional device as described above. By integrating the ring gear and the intermediate bracket with engineering plastic, the device structure is simplified, and the structure is made stronger at low manufacturing cost. The aim is to provide something advantageous.

An embodiment of this invention will be described below with reference to the drawings. In FIG. 2, reference numeral 19 denotes an intermediate bracket that is integrally manufactured by resin molding using engineering plastic material, and includes an annular flange portion 19c disposed between the planetary gear 10 and the DC motor 2, and A projection 19d formed by projecting the outer peripheral side of the flange 19c toward the planetary gear 10, and an internal gear 1 formed on the inner peripheral surface of the projection 19d and meshing with the planetary gear 10.
9a, and a bearing portion 19b formed by protruding the inner peripheral side of the flange portion 19c in a direction opposite to the projection portion 19d. The outer circumferential surface of the intermediate bracket 19 has a protruding portion 19d fitted into the spigot portion 3a of the bracket 3, and both end surfaces thereof are clamped by the bracket 3 and the DC motor 2. The rest of the configuration is the same as the conventional device shown in FIG. 1, so the same symbols will be used and the explanation thereof will be omitted. Further, since the operation of the above structure is similar to that of the conventional device shown in FIG. 1, a description thereof will be omitted.

According to the above configuration, the structural members are simplified, and the tooth portion 19a of the ring gear has a shape in which the end surface is fixed to a plate-like member, which has the effect of easily increasing the strength.

In the above description, the bracket 3 and the intermediate bracket 19 have a fitting structure, but the recess (or protrusion) is integrally formed on the outer peripheral surface of the intermediate bracket, while the protrusion (or recess) is formed on the bracket. By arranging them so that they fit into each other and receiving the rotational force exerted by the intermediate bracket, an even more reliable speed reduction mechanism can be obtained. Further, although the shaft bearing part of the intermediate bracket is used as the input rotating shaft part, the same effect can be obtained even if it is on the output side of the speed reduction mechanism.

As described above, according to this invention, the ring gear (internal gear) of the planetary gear reduction mechanism and the intermediate bracket provided in the reduction mechanism part are integrally molded with engineering plastics, which is a synthetic resin member. This structure simplifies the device, significantly reduces noise from the gear reduction section, and has the excellent effect of compensating for the decrease in strength due to plasticization at a low cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a conventional planetary gear type internal reduction type starter, and FIG. 2 is a sectional view of a main part of an embodiment of this invention. In the figure, 1 is a starter assembly, 2 is a DC motor,
3 is a bracket, 6 is an armature, 7 is a rotating shaft, 8 is a sleeve bearing, 9 is a spur gear, 10 is a planetary gear, 13 is a flange, 14 is an output rotating shaft, 19 is a ring gear assembly, 19a is an internal gear, 19
b is a bearing portion, 19c is a flange portion, and 19d is a protrusion portion. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A DC motor, a bracket that is fitted with the DC motor via a pilot part, a sun gear formed on the output rotation shaft of the DC motor, and a sun gear that meshes with the sun gear to rotate the output rotation shaft of the DC motor. A planetary gear reduction device having a planetary gear that reduces the speed of the motor, an annular flange disposed at an end of the DC motor, and a protrusion formed by protruding the outer peripheral side of the flange toward the planetary gear. , an intermediate bracket formed on the inner circumferential surface of the protrusion and having an internal gear meshing with the planetary gear, and integrally molded from engineering plastic; A starter characterized in that the starter is fitted into the spigot part of the bracket and both end surfaces of the protrusion are held between the bracket and the DC motor.