Quick-connect chuck mechanism for screwdriver bits and the like
A bit holder has a shank at a proximal end thereof and a blind bit-accepting hole at a distal end thereof, shaped to receive a correspondingly-shaped tool bit. The bit holder has at least one locking mechanism comprising an opening defined in the bit holder, opening into a side of the bit-accepting hole. A locking element in the opening is moveable towards the opening to contact a tool bit in the bit-accepting hole. The bit holder has a sleeve around a body portion of the bit holder, overlying the opening and biased by a spring towards a normal position. The sleeve has an internal ramp angled to contact the locking element to urge the locking element towards the tool bit as the sleeve is moved into the normal position, and to accommodate the locking element when the sleeve is moved from the normal position against the force of the spring.
1. A bit holder having a shank at a proximal end thereof and a blind bit-accepting hole at a distal end thereof, said bit-accepting hole being shaped to receive a correspondingly-shaped tool bit, the bit holder having at least one locking mechanism comprising a first angled path defined in said bit holder, opening into a side of said bit-accepting hole, extending away from said bit-accepting hole at an acute angle from a central axis of said bit holder toward the proximal end, and a first locking element slideable in said first angled path, such that a portion of said first locking element associated with the distal end extends slightly into said bit-accepting hole, said bit holder further comprising a sleeve mounted around the body of the bit holder, the sleeve biased by a spring to urge said first locking element towards said bit-accepting hole, connected to said first locking element such that moving said sleeve towards the proximal end retracts said first locking element from said bit-accepting hole, wherein said first locking element comprises a ball and wherein said sleeve has a hook portion extending therefrom to capture said ball the bit holder further comprising a second angled path defined in said bit holder, opening into a side of said bit-accepting hole, extending away from said bit-accepting hole at an acute angle from a central axis of said bit holder toward the distal end, and comprising a second locking element slideable in said second angled path, the sleeve connected to said second locking element, whereby said tool bit is locked against movement towards either the proximal end and the distal end until said sleeve is moved.
2. A bit holder as in claim 1 , comprising more than one said locking mechanism spaced apart radially.
3. A bit holder as in claim 1 , further comprising a spring-loaded plunger mounted in a proximal end of said blind bit-accepting hole, to eject said tool bit when said locking element is released by moving said sleeve.
4. A bit holder as in claim 1 , wherein said tool bit and said bit-accepting hole are hexagonal in cross-section.
5. A bit holder as in claim 1 , wherein said tool bit and said bit-accepting hole are non-circular in cross-section.
6. A bitdriver comprising a bit holder as in claim 1 , and having a handle mounted on said shank.