Patent US 5,337,920

A general purpose system for the storage and retrieval of articles having nested sets of rotatable platters or of various perimeters such that each set fits inside the perimeter of the next larger sized platter. All platters have storage positions or bins in which articles are stored. Bins are positioned so that one side is adjacent to the perimeter of the platter. All platters are mounted so that a part of their perimeter is adjacent to the perimeter of the platter on which they are mounted. This arrangement makes all storage positions available at the edge of the largest or main platter by rotating a subset of the smaller platters. The main platter can be rotated to a serving window making all storage positions on the platter available at the serving window. The geometry of the circular arrangement make the number of storage positions on a main platter vary with the square of the radius of the main platter whereas the time it takes to fetch a storage location varies with the radius. Smaller platters can be removed and replaced by bins allowing the system to accommodate bins with a wide variety of sizes and shapes. Several different drive assemblies can be interchangeably or redundantly mounted to rotate the platters. A computer system controls the drive assemblies to automate and optimize the storage-retrieval process. The storage system may also use rotatably mounted nested sets of support arms.