The invention relates to a wear-monitoring device of a brush of a current-transferring device in an electric machine comprising a measuring element, which is arranged at a distance from the brush and forms an electrical capacitor together with the brush, the capacitance of which electrical capacitor depends on the position of the brush relative to the measuring element.

The invention relates to a wear-monitoring device of a brush of a current-transferring device in an electric machine comprising a measuring element, which is arranged at a distance from the brush and forms an electrical capacitor together with the brush, the capacitance of which electrical capacitor depends on the position of the brush relative to the measuring element.

A brush holder apparatus has a stationary support member having two opposing grooves, a fork electrical connector, and a conductive bar configured to pass through a portion of a main body of the stationary support member. The conductive bar provides electrical conductivity with a collector mount and the fork electrical connector. A brush holder is configured to be releasably affixed to the stationary support member, and has two rails configured to slide along the grooves. The brush holder has a knife electrical connector configured to mate with the fork electrical connector. A brush spring is clipped on the brush holder, and the brush spring presses a brush against a collector of a dynamoelectric machine. A brush lead is connected to the brush and a brush terminal. The brush lead is an elongate conductive member, and a brush wear indicator is disposed over the brush lead.

A brush holder apparatus has a stationary support member having two opposing grooves, a fork electrical connector, and a conductive bar configured to pass through a portion of a main body of the stationary support member. The conductive bar provides electrical conductivity with a collector mount and the fork electrical connector. A brush holder is configured to be releasably affixed to the stationary support member, and has two rails configured to slide along the grooves. The brush holder has a knife electrical connector configured to mate with the fork electrical connector. A brush spring is clipped on the brush holder, and the brush spring presses a brush against a collector of a dynamoelectric machine. A brush lead is connected to the brush and a brush terminal. The brush lead is an elongate conductive member, and a brush wear indicator is disposed over the brush lead.

A system for monitoring the wear state of a carbon brush of a brush holder assembly in which the length of the carbon brush is diminished from an initial length as an end of the carbon brush wears away during use. The system includes a wear state monitor, including a sensor, coupled to the carbon brush. The wear state monitor is configured to rotate as the length of the carbon brush diminishes. The sensor is configured to measure an angular displacement of the wear state monitor as the wear state monitor rotates. The measured angular displacement of the wear state monitor correlates to an amount of diminution in the length of the carbon brush.

A system for monitoring the wear state of a carbon brush of a brush holder assembly in which the length of the carbon brush is diminished from an initial length as an end of the carbon brush wears away during use. The system includes a wear state monitor, including a sensor, coupled to the carbon brush. The wear state monitor is configured to rotate as the length of the carbon brush diminishes. The sensor is configured to measure an angular displacement of the wear state monitor as the wear state monitor rotates. The measured angular displacement of the wear state monitor correlates to an amount of diminution in the length of the carbon 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.

A brush for an electric machine includes at least one brush body having an electrical resistance, which is configured to electrically contact at least one component moving relative to the brush body during operation of the electric machine, and which sustains wear during the operation of the electric machine along a wear direction, as a result of friction contact with the component. The brush includes a detection device configured to determine wear of the brush body, where the detection device comprises a plurality of detection zones which are mutually spaced apart along the wear direction, the respective electrical resistance of which differs from the electrical resistance of the brush body.

A brush for an electric machine includes at least one brush body having an electrical resistance, which is configured to electrically contact at least one component moving relative to the brush body during operation of the electric machine, and which sustains wear during the operation of the electric machine along a wear direction, as a result of friction contact with the component. The brush includes a detection device configured to determine wear of the brush body, where the detection device comprises a plurality of detection zones which are mutually spaced apart along the wear direction, the respective electrical resistance of which differs from the electrical resistance of the brush body.

A method for measuring a state of wear of a consumable friction element, a measuring device and a friction element, in particular a brush or the like. The measuring device includes a sensing device having a sensor. A magnetic field can be produced by means of the sensor, and the friction element can be moved in the magnetic field relative to the sensor. The measuring device comprises an indicator that can be attached to the friction element. The indicator comprises a ferromagnetic, antiferromagnetic and/or ferrimagnetic substance, and a change in the magnetic field can be detected by means of the sensing device as a result of a change in the position of the indicator relative to the sensor.