Brush unit for an electric machine, spring and seal arrangement for the same, and method for the production thereof

Abstract

The invention relates to a brush unit for an electric machine having a simple and low-cost but robust design, and that can be assembled at low cost using simple process steps, comprising four ring-shaped board elements (1, 3, 5, 7) stacked on each other, namely two outer circuit boards (1, 3), each of which is electrically conductively connected to one or more brushes (9), and two guide boards made of electrically insulative material disposed therebetween, comprising a shape having protrusions and recesses for forming radial guides (21) for the brushes (9) and receptacles (40) for springs (35) acting on the brushes. The springs are spiral springs wound around a mandrel (39), the flat ends thereof protruding past the springs being rotationally fixedly guided in a guide groove of each receptacle (40) and able to engage behind a stop (43). In order to assemble the brush unit, the circuit and guide boards (1, 3, 5, 7) are stacked on each other in the axial direction and riveted, then the brushes (9) are inserted in the guides (21) in the radial direction and the springs (35) are placed in the receptacles (40).

Description

technical field [0001] The invention relates to a brush set for a motor. A preferred field of application for such brush sets is electric motors for motor vehicles, in particular starters (starter motors) for internal combustion engines. Background technique [0002] People are constantly putting forward higher requirements on the life and power yield of automobile starters, partly due to the continuous improvement of environmental requirements. For example, in order to save fuel, a start-stop function has been installed in many new cars. In this function, the engine stops automatically when the car stops, and starts automatically when it is started. This necessarily leads to an increased load on the starter due to the necessary measures such as increasing the conductor cross-section and / or increasing the number of brushes, thus increasing the material outlay. As a result, high material costs must be counteracted by keeping installation costs as low as possible. Contents...

AI Technical Summary

Problems solved by technology

This necessarily leads to an increased load on the starter due to the necessary measures such as increasing the conductor cross-section and / or increasing the number of brushes, thus increasing material costs

As a result, high material costs must be counteracted by keeping installation costs as low as possible

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