Patent ID: 7389993
Filing Date: 2008-06-24
Classification: B23B,Y10T

Abstract:
1. A drill chuck comprising: a chuck body rotatable about a chuck axis and provided centered on the axis with an annular array of teeth; a plurality of jaws angularly spaced on the body about the axis and radially displaceable relative to the body; a tightening ring axially fixed but rotatable about the axis on the body in a tightening direction and in an opposite loosening direction; means including a pair of screwthread formations between the tightening ring and the jaws for moving the jaws radially together on rotation of the tightening ring in the tightening direction and for moving the jaws radially apart on rotation of the tightening ring in the loosening direction; a pawl engageable with the teeth and angularly fixed on the tightening ring, the pawl being radially displaceable between a retaining position engaging the teeth and preventing rotation of the body relative to the tightening ring in the loosening direction and a freeing position disengaged from the teeth and permitting free rotation of the body relative to the tightening ring in both directions; an adjustment sleeve axially fixed but at least limitedly angularly displaceable on the body relative to the tightening ring between a locked end position and an unlocked end position; means including a cam on the adjustment sleeve engageable with the pawl for displacing the pawl into the retaining position when the adjustment sleeve is in the locked end position and for displacing the pawl into the freeing position when the adjustment sleeve is in the unlocked end position; a locking part engageable with the pawl in the retaining position thereof; and means for pressing the locking part against the pawl in the retaining position thereof and thereby pressing the pawl against the teeth.