Quick-connect chuck mechanism for screwdriver bits and the like

Abstract

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 which includes an angled path defined in the bit holder, opening into a side of the bit-accepting hole, extending away from the bit-accepting hole in a proximal direction at an acute angle A from a central axis. A locking element is slideable in the path. A sleeve around the shank is biased towards the bit-accepting hole by a spring, such that a distal end of the locking element extends slightly into the bit-accepting hole. Moving the sleeve towards the proximal end of the bit holder retracts the locking element from the bit-accepting hole, thereby releasing the bit. A spring-loaded plunger in the blind hole may be used to eject the bit automatically when the locking mechanism is released by the sleeve.

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 an angled path defined in said bit holder, opening into a side of said bit-accepting hole, extending away from said bit-accepting hole in a proximal direction at an acute angle A from a central axis of said bit holder, and a locking element slideable in said path, such that a distal end of said locking element extends slightly into said bit-accepting hole, said bit holder further comprising a sleeve mounted around said shank, biased by a spring to urge said locking element towards said bit-accepting hole, connected to said locking element such that moving said sleeve towards the proximal end of said bit holder retracts said locking element from said bit-accepting hole. 
     
     
         2 . A bit holder as in  claim 1 , wherein said locking element comprises a pin connected to said sleeve, for a distal end of said pin to contact a tool bit. 
     
     
         3 . A bit holder as in  claim 1 , wherein said locking element comprises a pin connected to said sleeve, said pin having a roller mounted at a distal end thereof to contact a tool bit. 
     
     
         4 . A bit holder as in  claim 1 ; wherein said locking element comprises a ball and wherein said sleeve has a hook portion extending therefrom to capture said ball. 
     
     
         5 . A bit holder as in  claim 1 , 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 in a distal direction at an acute angle A from a central axis of said bit holder, and comprising a second locking element, whereby said tool bit is locked against movement in both directions until said sleeve is moved. 
     
     
         6 . A bit holder as in  claim 5 , comprising more than one said locking mechanism spaced apart radially. 
     
     
         7 . A bit holder as in  claim 6 , further comprising a spring-loaded plunger mounted in a proximal end of said blind hole, to eject a said tool bit when said locking element is released by moving said sleeve. 
     
     
         8 . A bit holder as in  claim 7 , wherein said bit and said bit-accepting hole are hexagonal in cross-section. 
     
     
         9 . A bit holder as in  claim 7 , wherein said bit and said bit-accepting hole are non-circular in cross-section. 
     
     
         10 . A bitdriver comprising a bit holder as in  claim 9 , and having a handle mounted on said shank. 
     
     
         11 . 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 an opening defined in said bit holder, opening into a side of said bit-accepting hole, and a locking element in said opening, said locking element comprising a rotatable eccentric cam, spring biased to rotate its largest radius away from said bit-accepting hole, said bit holder further comprising a sleeve mounted around said shank, spring-biased against said eccentric cam to prevent said eccentric cam from rotating its largest radius away from said bit-accepting hole. 
     
     
         12 . A bitdriver comprising a bit holder as in  claim 11 , and having a handle mounted on said shank. 
     
     
         13 . 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 an opening defined in said bit holder, opening into a side of said bit-accepting hole, and a locking element in said opening moveable towards said opening to contact a tool bit ins said bit-accepting hole, said bit holder further comprising a sleeve around a body portion of said bit holder, overlying said opening and biased by a spring towards a normal position, said sleeve having an internal ramp angled to contact said locking element to urge said locking element towards said tool bit when said sleeve is in said normal position, and to free said locking element when said sleeve is moved from said normal position against the force of said spring. 
     
     
         14 . A bitdriver comprising a bit holder as in  claim 13 , and having a handle mounted on said shank.