CHUCK FOR AXIALLY CLAMPING A TOOL TO A MACHINE TOOL SPINDLE

摘要

A rotary chuck for axially clamping a tool includes a spindle terminus forming part of a rotary machine tool spindle; a clamping element holder immobilized in the central bore of the spindle terminus; and a plurality of clamping elements circumferentially evenly distributed about the holder. Each clamping element is a one-armed spreading lever having a first end pivotally supported in the holder to provide for a pivotal movement of each clamping element in a plane containing the spindle axis. Each clamping element has a second end having a radially outwardly swung clamping position in which each second end is adapted to be clamped against an inner shoulder of a hollow tool shank received in the spindle bore for axially pulling the tool into engagement with a frontal end face of the spindle terminus. Each second end has a radially inwardly swung releasing position in which the tool is released from the chuck. There is further provided a clamping drive extending coaxially with the spindle axis and being operatively coupled to the clamping elements. The clamping drive is axially movable in a first direction for displacing the clamping elements into the clamping position and in a second direction for displacing the clamping elements into the releasing position.