JPS6330211Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of an electric motor for engine starting.
In particular, the purpose is to make the device smaller and lighter.

A conventional device of this type is shown in FIG. In the figure, reference numeral 1 denotes a rear bracket of an electric motor for starting the engine, which is fitted onto a yoke 2. 3 is a brush assembly screwed onto the rear bracket 1, the brush 4 is held by a brush holder 5, and one end is in sliding contact with the commutator 7 of the armature 6 to obtain the necessary commutating function. There is. 8 is the above rear bracket 1
This is a bearing device fitted to the armature 6, and supports the rear end portion of the rotating shaft 9 of the armature 6.

Next, the operation in the above configuration will be explained.
When the engine switch is closed, the armature 6 is energized via the brush 4 that is in sliding contact with the commutator 7.
Rotational force is generated. This rotational force is transmitted to the rotating shaft 9, and an engine (not shown) is started. Note that this reaction force at the time of starting is received by the sleeve bearing 8 that supports the rotating shaft 9.

In the conventional apparatus as described above, the rear bracket and the brush holder have a separate structure, which has the disadvantage of making the apparatus complicated and expensive.

This invention was made in order to eliminate the drawbacks of the conventional equipment as described above, and uses a face type commutator (flat type commutator) and molds the rear bracket and brush holder using synthetic resin molding. The purpose of the present invention is to provide an engine starting electric motor that is easy to assemble, compact, and lightweight.

An embodiment of this invention will be described below with reference to the drawings. In FIG. 2, reference numeral 10 denotes a rear bracket made of plastic, which has a bottomed cylindrical brush holder 10a integrally molded therein, and the brush 14 is supported by the holder 10a. The brush 14 is configured to be pressed forward by a brush spring 15 housed inside the brush 10a. 11 is an armature coil held on the rotating shaft 12 through its core; 13 is a face-type commutator that is attached to the rotating shaft 12 and has a brush 14 in sliding contact; A child coil 11 is provided, and the armature coil 11 is supported so that its end surface is located at the sliding contact surface with the brush 14. Note that the sliding surface is a face type commutator 13.
After the armature coil 11 is welded to the armature coil 11, the armature coil 11 is processed to have a flat surface by polishing or the like. Also,
A sleeve bearing 8 that supports the rotating shaft 12 is fitted into the central protrusion 10b of the rear bracket 10.

With the above configuration, rotational force is generated in the armature as in the conventional device shown in FIG. 1, and an engine (not shown) is started. Although the yoke biasing method (magnetic biasing method) is not specified in the above description, a field method such as a direct current series winding method or a permanent magnet method is applicable.

As described above, this invention forms the brush holder integrally with the rear bracket, supports the brushes within the brush holder, makes the brushes slide into contact with the face-type commutator, and penetrates the face-type commutator. Since the armature coil is connected to the sliding surface of the face-type commutator, the structure of the brush holding mechanism and the face-type commutator can be made smaller, making the entire device smaller and lighter. It has the advantage of being able to be made easily and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing a conventional engine starting electric motor, and FIG. 2 is a partial sectional view showing an embodiment of this invention. In the figure, 8 is a sleeve bearing, 10 is a rear bracket, 10a is a brush holder, 11 is an armature coil, 12 is a rotating shaft, 13 is a face type commutator,
14 is a brush, and 15 is a brush spring. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A rear bracket made of plastic,
A cylindrical brush holder with a bottom is formed integrally with the inner surface of the rear bracket, a brush is supported by the brush holder, and a brush holder is housed inside the brush holder to support the brush. A brush spring that presses and biases, a sleeve bearing fitted to the rear bracket, a rotating shaft supported by the sleeve bearing, and a face type commutator that is attached to the rotating shaft and on which the brush slides. and an armature coil held on the rotating shaft via a core, the end of which passes through the face-type commutator and is connected to the sliding surface thereof, and the end face of the armature coil is connected to the brush. An electric motor for starting an engine, characterized in that it is configured to make sliding contact.