Kinematic Couplings for Pallets in Flexible Assembly Systems

摘要

Flexible assembly systems use conveyors to transfer products through a series of workstations. The product being assembled is typically held in a fixture mounted on top of a pallet. Conventional approaches for locating the pallets often use precision ground pins and bushings for location. This technique requires clearance between the pin and bushings to accommodate manufacturing variation and prevent binding. For one system, this clearance limits the repeatability of the pallet to 100 microns. For high-precision assembly operations, the non-repeatability of the pallet can be one of the largest sources of variation and lead to low quality or porr yields. This paper presents kinematic couplings as an exact constrainc pallet used in a flexible assembly system for electrical connectors. The repeatability of the kinematic pallet was measured in fractory-like conditions. The repeatability was within 10 microns, which is about an order of magnitude improvement over a leading insutrial pallet.