Abstract: A holder for a tool or workpiece has a tubular working spindle centered on and rotatable about an axis, an elongated pulling element axially displaceable in the spindle and having a front end provided with holder jaws and a rear end with a forwardly directed face perpendicular to the axis. An actuating body axially displaceable in the spindle forward of the element face has an outwardly directed and rearwardly inwardly inclined face. A spring between the spindle and the body urges the body continuously backward. At least one wedge in the spindle between the body and the element face has a rear end face flatly abuttable with the element face, an inclined inner face flatly abuttable with the body face, and a forwardly outwardly inclined front end face.

Abstract: The tool spindle has a drive plate on which a cutter is mounted. Drive keys on the drive plate engage slots in the cutter so that the cutter rotates with the drive plate. A clamp bar is provided to clamp the cutter against the drive plate. The cutter is formed with clearances which register with the clamp bar when the cutter is rotated relative to the clamp bar, so that the cutter may be removed from the drive plate. A new cutter is then reverse rotated into a position in which it may be clamped by the clamp bar. A spring holds the clamp bar in its clamping position. The quick change system also includes two or more locking fingers which are activated by centrifugal force to maintain the cutter clamped to the drive plate even in the event of failure of the spring which normally holds the clamp bar in its clamping position.

Abstract: A machine tool chuck in which a wedge member is provided to cause radial displacement of workpiece clamping pawls for replacement. The replacement can be made with minimum variations in radial position at which the clamping pawls are relocated. To this end, the clamping pawls and slide blocks are slidably guided radially through a chuck body independently of each other. Each clamping pawl and each slide block are in slidable engagement with a sloping wedge action portion of an axial slidable wedge bar in such a way that axial displacement of the wedge bar will force both the clamping pawl and the slide block to move radially independently of each other while maintaining the geometric relationship therebetween. For replacement of the clamping pawl, the wedge bar is moved backward to cause its wedge action portion to be disengaged from the clamping pawl whereby the clamping pawl can be slid radially outwardly for replacement.

Abstract: An improved scroll chuck for holding a workpiece in a lathe including a jaw holder having a front side and a rear side, radially extending slots in the front side and means for attaching the holder to the lathe for turning about a central axis. Two or more jaw devices are mounted in the slots and are radially movable therein. A scroll member is rotatably mounted on the holder and has a spiral-shaped rib formed on a front surface thereof. This rib extends along recesses formed on the jaw devices whereby rotation of the scroll member causes the jaw devices to move in the radial direction. A pin member is arranged on one of the jaw devices and extends from a rearwardly facing surface of the device and into an elongate recess formed in the holder. This pin member prevents the jaw device from accidentally disengaging from the holder.

Abstract: A chuck having a sliding outer jaw is locked against any adjustment in radial position relative to the inner jaw on which it is moved radially by a radially movable pin which, in one radial position, prevents axial retraction of the post interconnecting inner and outer jaws for radial movement. The chuck utilizes a tool having a pair of radially movable means, one of which is capable of moving the post axially of the chuck after the other means has caused the post retention to be made inactive for preventing axial movement of the post.