Deutsche Carbone Ag

Jurgen Spangenberg

Arwed Uecker

Conrad H Reynvaan

Erhard Grohs

Lothar Biering

Klaus Groht

An improvement to an electric fuel pump which includes an electric motor with a rotating commutator defining an axial direction, a radial direction and a tangential direction, and having a circumferential surface, and a carbon brush having a contact surface contacting the circumferential surface of the commutator. The brush includes a gap extending from the contact surface in a radial direction and further extending through the brush in the axial direction, the gap reducing flotation of the carbon brush caused by a layer of fuel drawn between the carbon brush and the commutator. In an alternate embodiment, the brush includes a pressure relief hole extending from the contact surface completely through the brush in the radial direction.

Carbon brush for electric fuel pumps

A sliding contact member substantially free of the toxic metals lead and antimony, includes copper, carbon, and at least one added material which is selected from the group consisting of a metal and a metal alloy having a melting temperature which is substantially below that of copper. The sliding contact member contains less than 10 percent by weight of the at least one added material. The sliding contact member is electrically conductive and capable of carrying high current densities, and the at least one added material provides a good cleaning effect, promotes cooling of the sliding contact member during operation, and provides good slidability against a mating contact member. This is achieved by keeping the at least one added material separate from the copper so that alloy formation is inhibited and, preferably, prevented.

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Bad Vilbel, Germany

Jurgen Spangenberg