Werkzeugspannmechanismus und Zugstange

摘要

A fixed first sleeve and a movable second sleeve are arranged in a center through hole of a main spindle. Balls at the rear end of the second sleeve engage a recessed slope of the first sleeve and a recessed slope of a draw bar, thereby amplifying the urging force of a spring for urging the draw bar upward. Balls at the distal end of the second sleeve hold and pull in the head of the pull stud with the amplified force. The pull stud has an axial through hole and a hole that connects with the through hole and opens sideways. Compressed air passes through these holes, thereby cleaning the respective taper surfaces and end faces of the main spindle and a tool shank. Switching means is used to close the hole that opens sideways, whereby a cutting fluid is allowed to flow through the axial through hole only.