Novel ball transfer unit

摘要

A ball transfer unit adapted to receive cargo for movement thereover having a ball race assembly including a cup member having a cylindrical wall extending therearound and having a terminal end at the outer extremity of said cup. The wall in proximity to said terminal end is provided with external threads. A plurality of roller balls repose in the cup. A rotatable cargo engageable ball rests on the roller balls. A ball cover is provided to prevent inadvertent removal of the cargo engaging ball from said assembly while allowing free rotation thereof. The ball cover has a terminal end and, in proximity to said terminal end, the cover is provided with internal threads. The external and internal threads are engageable to hold the ball cover in place on the ball race assembly during normal use and the ball cover being readily disengageable to permit disassembly and cleaning of the components of the unit. The unit has a flat, planar bottom surface on which to rest during disassembly. The cup is supported around its periphery by an inwardly extending shoulder provided on the cylindrical wall. The cup supported by the shoulder together with the threads serve to improve the alignment of the ball and ball cover so that less dirt is admitted.