TOOL UNIT CLAMPING APPARATUS HAVING IMPROVED SHORT-STROKE LOCKING MECHANISM

摘要

A short-stroke clamping apparatus for detachably connecting a tool unit to a tool supporter is provided of the type having a canister member which includes apertures for admitting spherical locking elements, and a lock rod that is reciprocally movable a stroke distance along an axis and which has cam portions for moving the spherical locking elements through the canister apertures into engagement with the tool unit. In the clamping apparatus, the canister member apertures are elongated along the stroke axis. This allows the spherical locking elements to move axially along the cam portions of the lock rod as well as radially, such that locking engagement can be achieved with a shorter axial stroke movement of the lock rod. The aperture walls may also be angled to allow even greater axial movement of the locking elements, which not only further shortens the lock rod stroke, but can increase the gripping force that the clamping apparatus applies to the tool unit. The shorter lock rod stroke in turn advantageously shortens the tool envelope, and increases both the rigidity and life of the spring package that withdraws the lock rod. The aperture walls may also be angled to improve the force of locking engagement between the locking elements and the tool unit.