Brush holder for an electrical machine

Abstract

A brush holder for an electrical machine, and in particular a hammer brush holder, can include a carbon brush inserted with one of its ends provided with a brush shunt into a pot-shaped receptacle part of the brush holder. The carbon brush is retained in the receptacle part by means of clamping. A reliable clamping of the carbon brush is guaranteed by providing a scraper rib on at least one side wall of the receptacle part and designing it to ascend from the entry slot of the receptacle part toward its pot-like bottom with respect to its height and/or its width pointing into the receiving space of the receptacle part. The brush holder may be manufactured from plastic, and the carbon brush is inserted with a clamp locking force fit into a receiving opening of the brush holder. In order to be able to guarantee a secure fixed seating in any case in spite of the unavoidable tolerances in the case of mass production, at least one side wall of the insertion opening having a protruding scraper rib comes to rest against the carbon brush. The scraper rib is arranged or designed to make contact with the carbon brush in a way that allows lateral and/or vertical variation with increasing insertion depth of the carbon brush.