An indexing machine utilizes a rotating assembly for incrementally rotating a workpiece which is releasably held by a gripping mechanism adapted to rotate conjointly with the rotating assembly. The gripping mechanism is movable between a first position in which the gripping mechanism grips the workpiece and a second position in which the gripping mechanism releases the workpiece. The gripping mechanism is automatically and constantly urged towards its second position so as to facilitate the release of the workpiece from the gripping mechanism. Indexing plates, which determine the increments of rotation of the rotating assembly, are positioned at one end of the rotating assembly so that they may be quickly and easily removed. The rotating assembly includes a first member and a second member, which is mounted for reciprocating movement relative to the first member. A locking device releasably locks the second member to the first member so that the second member can rotate conjointly with the first member. When the second member is unlocked from the first member, the second member can be rotated relative to the first member.
A dividing head assembly comprises concentric outer and inner primary and secondary shafts journalled in a body member having a base for mounting the assembly on a machine tool bed in juxtaposition to a cutter. The inner shaft is coupled for rotation with the outer shaft and is axially slidably mounted in the outer shaft. The inner shaft has a workpiece holder at one end and a collar at the other end formed with a master thread and/or a master cam profile. A gear drive is provided for rotating the shafts, and the body member carries a follower for engaging the respective cam profile or master thread so that on rotation of the drive means the workpiece holder is provided with controlled rotation accompanied by axial movement thereof governed by the cam profile or master thread, for screw or cam forming a workpiece. A releasable coupling screw is operative between the shafts for locking the inner shaft against axial movement in the outer shaft so that with the follower disengaged from the cam profile or master thread, operation of the drive means provides rotation of the workpiece holder without axial movement thereof, for use of the device in the manner of a conventional dividing head.
