Patent ID: 7748302

Claim:
A workpiece exchanging apparatus for exchanging a machined workpiece with an unmachined workpiece, the workpiece exchanging apparatus comprising: a gripping arm provided at its two longitudinal end sections with gripping sections for gripping, respectively, a machined workpiece and an unmachined workpiece, the gripping arm being able to turn around a turn axis that is positioned at a longitudinal center section of the gripping arm and being able to move linearly in the axial direction of that turn axis; a first cam mechanism for making the gripping arm turn; and a second cam mechanism for making the gripping arm linearly move; wherein the gripping arm performs: an operation in which the gripping arm moves linearly from a standby position of the gripping arm to a workpiece handover position for handing over the machined workpiece and the unmachined workpiece, in order for the gripping sections to grip the machined workpiece and the unmachined workpiece; an operation in which the gripping arm moves linearly from the workpiece handover position to a workpiece withdrawal position for withdrawing the machined workpiece and the unmachined workpiece received at the workpiece handover position; an operation in which the gripping arm turns such that the positions of the machined workpiece and the unmachined workpiece gripped by the gripping sections are swapped; an operation in which the gripping arm moves linearly from the workpiece withdrawal position to the workpiece handover position, in order for the gripping sections to release the machined workpiece and the unmachined workpiece; and an operation in which the gripping arm moves linearly in order to return from the workpiece handover position to the standby position; and the workpiece exchanging apparatus further comprising: a support shaft supporting the gripping arm such that the central axis of the support shaft coincides with the turn axis, the support shaft turning around the central axis together with the gripping arm and moving linearly in the axial direction of the central axis together with the gripping arm.