Abstract: A collet assembly for releasably holding a tool shaft of the type having an indexing depression in the surface thereof includes an elongate core having a bore in one end thereof for receiving the tool shaft. A retainer extending transversely through the core is shiftable into a locking position within the depression in order to prevent rotation of the shaft relative to the core. A tapered sleeve longitudinally slidable over the core engages and drives the retainer into the core. A collar threadably mounted on a core draws the sleeve in one longitudinal direction over the core in order to maintain the sleeve in a position locking the retainer in place.

Abstract: Apparatus for dressing abrasive wheels employed for grinding involute surfaces such as involute gear teeth includes a fixture for generating involute curves cooperatively coupled with a turntable and a dressing tool. The fixture includes a carriage bar reciprocably mounted on the turntable which drives the dressing tool. The carriage bar is captured between a stationary base circle disc and a pair of laterally movable rollers mounted on a rotatable portion of the fixture. Rotation of the fixture produces lateral translation of the carriage bar in a manner to generate involute movement of the tool. The fixture is swingably mounted to allow the mounting position of the carriage bar to be easily changed in order to generate a mirror image of the involute curve. The fixture and turntable are mounted on a base for freedom of movement along two perpendicular axes to permit rapid indexing and set up.