A contact-making rotary transmission includes a brush forming an electrically conductive sliding contact element and a contact path of electrically conductive material for contact with the brush. The brush is guided and/or held by an arrangement which includes a plurality of carrier segments arranged axially behind one another. Each carrier segment has attached thereto a brush receptacle such as to define a first gap between the carrier segment and the brush receptacle. The brush receptacle includes a stationary receiving shaft which is formed by walls and configured to receive the brush, and a guide element which is provided on a wall of the receiving shaft so as to define a second gap between the brush and the wall. At least one of the walls includes an opening in communication with the first and second gaps to allow a flow of cooling air for cooling the brush.

Example brush holder assemblies of an electric machine are disclosed. An example brush holder assembly of an electric machine includes a carbon brush including an upper surface and a lower surface opposite the upper surface. The brush holder assembly also includes one or more lead wires extending out of the carbon brush at an insertion point on the upper surface and a first cavity extending into the carbon brush from the upper surface at a location spaced away from the insertion point of the one or more lead wires and unobstructed by the one or more lead wires.

The embodiments of the present disclosure provide a carbon brush holder having internal surfaces which surround a space for bearing a carbon brush, wherein a heat dissipating slot is disposed at an internal corner of the carbon brush holder. The embodiments of the present disclosure further provide an electric motor. In the embodiments of the present disclosure, heat accumulated at the internal corners of the carbon brush holder can be dissipated rapidly because of the heat dissipating slots disposed at the internal corners, such that an excessively high temperature at the internal corners of the carbon brush holder is prevented and a risk of melting the plastics at the internal corners of the carbon brush holder is reduced, thereby increasing the life of the carbon brush holder and the carbon brush.

A method for treating a surface of a brush holder apparatus, where the brush holder apparatus is configured for use in a dynamoelectric machine, includes an electropolishing step that electropolishes the surface of the brush holder apparatus. An anodizing step anodizes the surface of the brush holder apparatus. The electropolishing step is performed before the anodizing step.

A contact-making rotary transmission includes a brush forming an electrically conductive sliding contact element and a contact path of electrically conductive material for contact with the brush. The brush is guided and/or held by an arrangement which includes a plurality of carrier segments arranged axially behind one another. Each carrier segment has attached thereto a brush receptacle such as to define a first gap between the carrier segment and the brush receptacle. The brush receptacle includes a stationary receiving shaft which is formed by walls and configured to receive the brush, and a guide element which is provided on a wall of the receiving shaft so as to define a second gap between the brush and the wall. At least one of the walls includes an opening in communication with the first and second gaps to allow a flow of cooling air for cooling the brush.

A contact-making rotary transmission includes a brush forming an electrically conductive sliding contact element and a contact path of electrically conductive material for contact with the brush. The brush is guided and/or held by an arrangement which includes a plurality of carrier segments arranged axially behind one another. Each carrier segment has attached thereto a brush receptacle such as to define a first gap between the carrier segment and the brush receptacle. The brush receptacle includes a stationary receiving shaft which is formed by walls and configured to receive the brush, and a guide element which is provided on a wall of the receiving shaft so as to define a second gap between the brush and the wall. At least one of the walls includes an opening in communication with the first and second gaps to allow a flow of cooling air for cooling the brush.

A brush holder has a core side position regulator engaged with a first connection plate to regulate a relative position. The core side position regulator has a projection part projected toward an armature core in the axial direction, and a fitting groove portion defined on both sides of the projection part in a circumferential direction. The relative position in the circumferential direction is regulated by an engagement between the projection part and a slit of the first connection plate. The relative position in the axial direction is regulated by an engagement between sides of the slit and the fitting groove portion. A width of the projection part in the circumferential direction is larger than a width of a brush in the circumferential direction.

A marking system for knowing precisely at which location on an electrical device a used brush and associated brush holder assembly were positioned to evaluate whether abnormal brush wear, abnormal operation or other anomaly is occurring and performing maintenance and/or replacement of components as needed.

A marking system for knowing precisely at which location on an electrical device a used brush and associated brush holder assembly were positioned to evaluate whether abnormal brush wear, abnormal operation or other anomaly is occurring and performing maintenance and/or replacement of components as needed.

A brush lead guide for a brush holder assembly configured to retain the leads extending from a brush in a desired position/orientation to ensure the leads do not interfere with movement of the brush within the brush holder. In some instances, the lead guide includes a first guide rail including a channel for receiving a first lead of the brush and a second guide rail including a channel for receiving a second lead from the brush. The lead guide maintains the leads in a position such that the leads are held within the width of the opening of the brush holder to ensure the leads do not interfere with movement of the brush within the brush holder during use of the brush holder assembly.