A brush apparatus for a slip ring system of a current-energized electric machine for a motor vehicle is provided for supplying a rotor of the electric machine with current, wherein the brush apparatus is securable to a component of the electric machine that is mounted in fixed relation to the rotor. The brush apparatus includes a brush carrier having a cartridge-type holder and a brush arranged in the cartridge-type holder and forming a sliding contact with a slip ring of the slip ring system. The brush apparatus also includes a retaining device, formed from an electrically insulating material for retaining the brush carrier, which has a securing region for securing the brush apparatus on the component, and a heat-conducting core enclosed in the retaining device, which is exposed for the purpose of heat dissipation at least in the securing region of the retaining device that is couplable to the component.

A carbon brush unit for a direct current-excited brushed motor may include a carbon brush and a carbon brush holder which is formed to receive the carbon brush. An outer side of the carbon brush and/or an inner side of the carbon brush holder are formed such that in the assembled state of the carbon brush unit defined contact regions and air channels located therebetween result between the outer side of the carbon brush and the inner side of the carbon brush holder in order to dissipate heat, wherein the contact regions are less than 60% of the overall surface of the inner side of the carbon brush holder, wherein the outer side of the carbon brush has a nanostructuring which forms the defined contact regions and air channels.

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 drive device for a hydraulic pump of a braking system for a motor vehicle includes a housing, a rotor, a rotor shaft mounted in the housing and supporting the rotor, and a commutator arranged in the housing. The commutator includes at least one commutator brush held by a brush holder. The commutator brush cooperates with a commutator ring arranged on the rotor shaft in a non-rotatable manner. The brush holder includes a sealing ring assigned to the commutator which is arranged coaxially to the rotor shaft and interacts with the rotor shaft in a sealing manner.

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.

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.

This brush holder assembly includes: a brush holder formed in a disk shape by molding of insulating resin, and including a pair of box fixing sections each including a groove formed from an outer peripheral side toward inside: and brush box assemblies each having a brush box which houses a brush therein, each of the brush box assemblies being disposed in the box fixing section. Each of the brush box assemblies is formed of box-like metal, and has a plurality of mounting legs. Additionally, each of the box fixing sections of the brush holder has a plurality of mounting holes. In this brush holder assembly, these mounting legs are inserted into the respective mounting holes, and the brush box assembly is fixed. Furthermore, in the brush holder assembly of the present invention, the brush holder assemblies face the brush holder through gaps. Additionally, a commutator motor of the present invention includes the above brush holder assembly.

A carbon brush for transferring high currents having a connective piece for connecting an electric conductor and a consumable contact piece having a contact surface formed for abutting against a commutator element. The connective piece has a silver content of approximately 5% by weight to approximately 39% by weight and the contact piece has a silver content of approximately 40% by weight to 100% by weight.

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.