JPH1023716A - Carbon brush - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent chattering between a commutator and a brush, to prevent brush loss or surface roughness of a commutator surface,
An object of the present invention is to provide a brush with a good rectification state. SOLUTION: A commutator non-contact surface at both ends with respect to a commutator contact surface formed at a center portion of a sliding surface with a commutator at a tip end of a brush body has an R larger than R at a central portion or a sliding direction. The brush is formed with a right-angled surface. Chattering between the edges of both ends of the commutator and the brush in the sliding direction during initial commutation can be suppressed, and brush loss or surface roughness of the commutator can be prevented, resulting in a stable commutation state without deterioration in characteristics. Brush.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon brush for a commutator motor used in a household vacuum cleaner or the like.

[0002]

2. Description of the Related Art A commutator motor used in a household vacuum cleaner or the like performs a break-in operation after the motor is assembled for stabilization of characteristics and quality inspection. In order to improve productivity, it is required to reduce the running-in operation time, and a carbon brush (hereinafter referred to as a brush) used for the brushing is required to have a good initial familiarity with the commutator.

[0003] A conventional brush will be described below.
FIG. 4 is a plan view of a conventional brush, and FIG. 5 is an enlarged view of an initial sliding surface between the conventional brush and a commutator.

In FIGS. 4 and 5, reference numeral 1 denotes a commutator, and reference numeral 2 denotes a brush having an R surface 2a formed at the tip thereof for sliding with the commutator. Reference numeral 3 denotes a pigtail buried at the top of the brush 2.

[0005] In order to improve initial familiarity with the commutator with the brush constructed as described above, the R surface 2a formed at the center of the sliding surface with the commutator at the tip of the brush body has an outer diameter of the commutator. It was formed identically to R.

[0006]

However, in this brush, in order to improve the initial familiarity with the commutator, the R surface formed at the center of the sliding surface with the commutator at the tip of the brush body has an outer diameter of the commutator. Because it is formed the same as R, the outer diameter of the commutator becomes smaller than R due to variations in the R surface processing of the brush, and chattering occurs between the edges at both ends in the sliding direction of the commutator and the brush during initial commutation. However, there has been a problem that the brush is broken or the surface of the commutator surface is roughened due to chattering, and the commutation state is deteriorated and the characteristics are deteriorated.

The present invention solves the above-mentioned conventional problems, suppresses chattering between the commutator and the brush, prevents breakage of the brush or roughening of the commutator surface, and improves the commutation state. It is intended to provide a brush.

[0008]

In order to achieve this object, a brush according to the present invention comprises a commutator contact surface formed on a sliding surface of a brush body at a tip end thereof and a commutator non-contact surface at both ends. With the brush formed by the above, the sliding surface formed at the brush tip becomes smooth, and the angle of the edge becomes gentle. Suppress chattering between the commutator and the brush during the initial commutation with the brush, and prevent brush loss or surface roughness of the commutator surface,
The rectification state becomes good.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In a carbon brush of the present invention, a sliding surface of a commutator provided at a tip is provided on a commutator contact surface having the same curved surface as an outer peripheral curved surface of a commutator, and on both sides of the commutator contact surface. And a commutator non-contact surface.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 is a front view of a brush according to Embodiment 1 of the present invention, and FIG. 3 is an enlarged view of an initial sliding surface between a brush and a commutator. Reference numeral 2a denotes a commutator contact surface having the same outer diameter R as the commutator 1 with which the commutator 1 contacts. Both ends of the commutator contact surface 2a have a larger R than the outer diameter of the commutator 1.
It has a commutator non-contact surface 2b that is a curved surface. As described above, the edge portion where the contact surface 2a and the non-contact surface 2b of the motor intersect is smooth, and the occurrence of chatter between the brushes can be suppressed during the initial commutation of the brushes.

FIG. 2 is a front view of a brush according to a second embodiment. 2a is a commutator contact surface with which the commutator 1 contacts, and 2c is a commutator non-contact surface formed at right angles to the sliding direction. The sliding direction is a direction in which the carbon brush pushes against the commutator, and forms a non-contact surface so as to be perpendicular to the sliding direction.

[0012]

As described above, according to the present invention, the commutator contact surfaces formed at the center of the sliding surface with the commutator at the tip of the brush main body have the commutator non-contact surfaces at both ends thereof at the center. By making the brush formed with a surface perpendicular to the R or sliding direction larger than R, the occurrence of chattering between edges of both ends of the commutator and the brush in the sliding direction during initial commutation is suppressed, Since the loss of the brush or the roughening of the surface of the commutator can be prevented, it is possible to obtain a brush capable of obtaining a stable commutation state without deterioration in characteristics.

[Brief description of the drawings]

FIG. 1 is a front view of a brush according to a first embodiment of the present invention.

FIG. 2 is a front view of a brush according to a second embodiment of the present invention.

FIG. 3 is an enlarged view of an initial sliding surface between a brush and a commutator according to the first embodiment of the present invention.

FIG. 4 is a plan view of a conventional brush.

FIG. 5 is an enlarged view of a conventional initial sliding surface between a brush and a commutator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Commutator 2 Carbon brush 2a Commutator contact surface 2b, 2c Commutator non-contact surface 3 Pigtail

Claims (3)

[Claims] 1. A commutator contact surface having the same curved surface as the outer peripheral curved surface of a commutator and a commutator non-contact surface located on both sides of the commutator contact surface. Composed carbon brush. 2. The carbon brush according to claim 1, wherein the non-contact surface of the commutator has a curved surface that is larger than an outer peripheral curved surface of the commutator. 3. The carbon brush according to claim 1, wherein the non-contact surface of the commutator is formed at right angles to the sliding direction.