Patent ID: 8678725

Claim:
A bit retaining system for retaining a bit in a rotary tool, the system comprising: a collet assembly including: a spindle operable to rotate about a spindle axis, the spindle comprising an internal channel and having a threaded external surface, a collet operable to receive a shank of the rotary tool bit disposed within the internal channel, wherein the collet is configured to move axially with respect to the spindle, a collet nut in threaded engagement with the external thread of the spindle, the collet nut restricting the axial movement of the collet with respect to the spindle, wherein the collet nut comprises a plurality of gear teeth that define a collet gear; and a control assembly comprising: a control gear, a displaceable gear engaged with the control gear, wherein the displaceable gear is configured to move from a first gear position, in which the displaceable gear is disengaged from the collet gear, to a second gear position, in which the displaceable gear engages the collet gear, and a pin translateable in a direction generally perpendicular to the spindle axis and engagable to a notch on the spindle, the notch being adapted to receive the pin, wherein, when the displaceable gear is in its second position, a rotary force applied to the control gear causes a corresponding rotation in the collet gear to axially drive the collet nut axially along the spindle.