1. Field of the Invention
This invention relates to self-aligning roller casters and, in particular, to roller assemblies useful in aircraft cargo loading systems.
2. Brief Statement of the Prior Art
Aircraft cargo loading systems commonly employ roller trays in which a plurality of rollers are mounted on a tray support that is secured to the cargo floor of the aircraft. The rollers are at convenient spacings to permit cargo pallets to be freely moved across the floor. In some applications, needle rollers are employed, however, these rollers provide only uni-directional movement of the cargo.
A recent development in cargo loading systems has been a self-aligning roller assembly which is described in U.S. Pat. No. 3,435,938. This assembly employs a pair of rollers that are mounted on upright standards that are laterally offset on a rotationally mounted base plate. This assembly permits free directional movement of cargo, however, it requires the use of two individual rollers which are mounted on upright flanges carried by the rotatable base member. The structure is not readily flush-mounted in the tray but projects therefrom. Additionally, the structure is relatively complex in assembly.