Brush holder assembly having snap-in replaceable commutator brush holder

Abstract

A brush holder plate assembly comprising a brush holder plate fabricated from electrically insulating thermoplastic material and having a plurality of sets of spaced-apart, parallel, raised guiding and support rails integrally formed on one surface of the plate. The plate further has a centrally formed aperture of sufficient cross sectional dimension to be slipped over the commutator of an electric machine after complete assembly of all the parts of the machine. The sets of spaced-apart, parallel, raised guiding and support rails project radially outward away from the centrally formed aperture like the spokes of a wheel. A plurality of snap-in-place, brush holder cartridges are removably secured by slide catches to the respective sets of spaced-apart parallel raised guiding and support rails for physically supporting commutating brushes in an array surrounding the commutator of the electric machine with one exposed end of each brush in physical and electrical contact with the commutator. For this purpose, the brush holder cartridges each further include biasing springs for spring tensioning brushes into physical and electrical engagement with the commutator of an electric machine to supply or conduct electric current between the commutator and the brush and the electric current supply.