Datum Location Employing Retractable Ball Transfer Units
Original Publication Date: 1988-Sep-01
Included in the Prior Art Database: 2005-Feb-15
To locate a subassembly with a heavy aluminium base casting onto fixed vertical steel datums in a work station, the subassemblies are moved into position across a number of raised ball transfer units until they register with fixed horizontal datums. The transfer units are then pneumatically lowered to lower the subassemblies onto the vertical datums. In an assembly line a heavy subassembly is loaded to various work and test stations, using a loading carousel. Typically, the subassembly is loaded on to three Z axis fixed hardened steel datums that are part of the station base plate. It is then pushed up to three fixed X and Y datums. The amount of movement is approximately 3 mm. Friction welding takes place between the soft aluminium casting underside of the subassembly and the Z datums.