Patent attributes
An extended life ball transfer unit has a housing with a well of generally cup-shaped configuration with at least the lower portion of its surface being defined by a pair of radii mutually offset to opposite sides from its vertical axis to generate a gothic church arch cross section. A passage extends therethrough at the base of the housing well. Sealed in the well is a spherical conveyor ball having a radius of smaller length than the radii defining the lower surface of the well, and the well defining radii having their origins above the center of the conveyor ball. A multiplicity of spherical bearing balls is disposed between the conveyor ball and at least the lower portion of the well. The bearing balls support the conveyor ball and transferring the load from the conveyor ball to the housing over an annular area defined by an arc of about 5-15° with its center spaced about 30°–40° upwardly from the passage. A annular cap is seated in the upper portion of the well and has an inner surface portion bearing against the surface of the conveyor ball to provide a sealing action limiting debris from passing into the lower portion of the well.
