Rotary table drive mechanism

摘要

A driving apparatus for rotating a rotary table is described including a drive mechanism and a guide apparatus. The drive mechanism includes a drive roller which contacts a peripheral surface of the rotary table to rotate the table, a support element and a press-on element which hold the drive roller against the table and apply compensating forces which prevent the drive mechanism from applying distorting forces to the support bearings of the table. The drive mechanism is guided at the periphery of the table by a pair of guides which permit substantially friction free translation of the drive mechanism in a plane perpendicular to the axis of rotation of the table while preventing rotation of the drive mechanism or translation out of the plane.