Tap member with axially adjustable contact for multi-conductor electrical track

Claim 1

A universal tap member adaptable for drawing power from one of three separate main circuits carried by an electric power distribution track of generally inverted U configuration, said track having a downwardly open channel and including insulation means carrying first and second vertically and horizontally offset pairs of parallel elongate conduits, said tap comprising a base portion adapted to engage against said channel, a bearing member formed on said base portion, a non-conductive spindle rotatably mounted in said bearing member from a first to a second position, a neutral contact member fixedly mounted to said spindle and positioned to engage a selected one of said conduits responsive to rotation of said spindle to said second position, an elongate conductor shaft of regular cross section mounted on said spindle and electrically isolated from said neutral contact, said shaft having its longitudinal axis concident with the axis of rotation of said spindle, a live contact member mounted on said spindle and including a commutator portion slidingly engaging said shaft in electrical contact therewith, said live contact member being shiftable axially of said spindle, complemental stop means interposed between said live contact member and said spindle for supporting said contact means adjustably in one of three discrete positions relative to said shaft, said contact means including a longitudinally directed contact portion electrically connected to said commutator and positioned to engage a selected conduit other than said one conduit in accordance with the adjusted position of said contact member and spindle responsive to rotation of said spindle from said first to said second position.