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 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.

A grounding brush assembly including a grounding brush and a mounting plate configured to axially and radially retain the brush, the brush providing a support and a plurality of electrically conductive fibers mounted in the support. The mounting plate is at least partially coated with an electrically conductive coating.

A brush block assembly and a method of assembling the same are described. The brush block assembly includes two or more brushes arranged in one or more rows, each of the two or more brushes comprised of a pressed electrically conductive material with an integral lead wire and a terminal, and one or more terminal studs, each of the two or more brush blocks within a same one of the one or more rows being separated by one of the one or more terminal studs, a helical spring coupled respectively to each of the two or more brushes, and insulated wires from a power supply and the respective terminal of each of the two or more brushes within the same one of the one or more rows being retained by the one of the one or more terminal studs in the one of the one or more rows.

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.

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 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.

An electric machine having a field coil and a rotatable armature coil. A rotatable commutator is conductively coupled with the armature coil and has a plurality of contacts. A plurality of brushes are conductively engageable with the plurality of contacts wherein rotation of commutator about the rotational axis causes the plurality of contacts to sequentially engage the plurality of brushes as the plurality of contacts rotate about the rotational axis. The plurality of brushes includes at least one positive brush and at least one negative brush, the at least one positive brush being a multi-layer brush and the negative brush being a single layer block brush. The multi-layer brush may include a high-copper layer and a low-copper layer with the low-copper layer forming the trailing edge of the brush. The single layer brush may have a copper content greater than the high-copper layer of the multi-layer brush.