JP3708293B2 - Small motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a small motor mounted on a hydraulic unit for an automobile or the like.
[0002]
[Prior art]
In recent years, hydraulic units for automobiles and the like have been required to be small and light and low in cost, and at the same time have high waterproof performance. For this reason, there are an increasing number of cases where the waterproof performance is improved as a unit rather than a single motor.
[0003]
FIG. 3 shows the structure of a conventional small motor. A structure is known in which the motor 1 breathes by opening a hole in the bracket 9 so as to communicate with the breathing hole 12 of the unit 11.
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional configuration, the pressure inside the motor is kept constant, so that the brush powder flows out to the unit side when breathing, making it difficult to breathe due to clogging, and interfering with other parts in the unit. There was a fear.
[0005]
SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object of the present invention is to provide a small motor having high reliability by improving the quality as compared with the prior art.
[0006]
[Means for Solving the Problems]
The small motor according to the present invention has a brush holder in which a wall is provided on the outer periphery of the bracket breathing hole on the inner side of the motor, and a wall covering the wall is integrally formed of heat-resistant resin.
[0007]
Thereby, a small motor with high quality and high reliability can be obtained.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, there is provided a yoke having a bottomed hollow cylindrical shape and having a plurality of permanent magnets fixed to an inner peripheral surface thereof, an armature facing the permanent magnet, and a commutator. A rotor, a brush holder provided on the yoke side with respect to the opening end of the yoke and provided with a brush that slides on the commutator, and a bracket that closes the yoke opening end. A small motor that is mounted on a unit and performs a breathing action through the unit, and has a brush holder in which a wall is provided on the outer periphery of the bracket through-hole on the yoke side, and a wall that covers the wall is integrally formed of heat-resistant resin. This is a small motor that prevents clogging on the unit side and other parts to prevent the brush powder from flowing out of the motor when breathing is performed in order to keep the pressure difference inside the motor constant. Can interference is prevented with the effect that high reliability in high quality.
[0009]
The invention according to claim 2 of the present invention is characterized in that the bracket is made of a material having a constant thickness and the outer wall of the breathing hole is formed by burring, which is relatively inexpensive. It is possible to prevent clogging on the unit side and interference with other parts, and to obtain high quality and high reliability.
[0010]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0011]
The small motor according to the embodiment of the present invention includes a yoke 6 that is formed in a cylindrical shape with a bottom and has a plurality of permanent magnets 3 fixed to an inner peripheral surface thereof, and a rotor that includes an armature and a commutator facing the permanent magnet 3. 2, a brush holder 10 provided with a brush 4 that is mounted closer to the yoke than the opening end of the yoke 6 and slides on the commutator, and a bracket 9 that closes the yoke opening end. A bracket wall 9a is provided on the yoke side of the outer periphery of the hole, and a brush holder wall 10a that covers the bracket wall 9a is provided in the brush holder. is there.
[0012]
FIG. 1 is a half sectional view of a small motor according to an embodiment of the present invention, and FIG. 2 is a sectional view of a portion of a substantially bracket and a brush holder of the small motor according to the present invention.
[0013]
1 and 2, the bracket 9 has a bracket wall 9a on the outer periphery of the breathing hole, and a brush holder wall 10a that covers the bracket wall 9a is formed integrally with the brush holder 10 and a heat-resistant resin. Through 12, the motor 1 has a breathing action.
[0014]
【The invention's effect】
As described above, according to the present invention, when breathing is performed in order to keep the pressure difference inside the motor constant, it is possible to prevent the brush powder from flowing out from the inside of the motor. It is possible to prevent clogging in the case and interference with other parts, and to obtain an advantageous effect that high quality and high reliability can be obtained.
[Brief description of the drawings]
FIG. 1 is a half sectional view of a small motor showing an embodiment of the present invention. FIG. 2 is a partial sectional view showing an embodiment of the present invention. FIG. 3 is a partial sectional view of a conventional small motor.
DESCRIPTION OF SYMBOLS 1 Motor 2 Rotor 3 Permanent magnet 4 Brush 5 Brush box 6 Yoke 7 Counter output side bearing 8 Output side bearing 9 Bracket 10 Brush holder 11 Unit 12 Breathing hole

Claims (2)

A yoke formed in a cylindrical shape with a bottom and having a plurality of permanent magnets fixed to the inner peripheral surface thereof, a rotor composed of an armature and a commutator facing the permanent magnet, and the opening end of the yoke A brush holder provided on the yoke side and provided with a brush that slides on the commutator; and a bracket that closes the yoke opening end; and a bracket wall is provided on the yoke side of the outer periphery of the breathing hole of the bracket; A small motor that is mounted on a hydraulic unit or the like and has a breathing action through the unit, wherein a brush holder wall that covers the bracket wall is provided on the brush holder. 2. The small motor according to claim 1, wherein the bracket is made of a material having a constant thickness and the outer wall of the breathing hole is formed by burring.

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