Damaged bolt and screw removing devices
AssigneeCombined Products Co. #1 Inc.
InventorsBurton Kozak, Ira Kozak
Life of this patent
Estimating the term…
Abstract
A bit for removing a broken fastener comprises a tip from which extend two or more notches separated by traction or biting surfaces formed from two-sided frusto-conically-shaped regions. The surfaces are bounded on one side by a nonlinear cutting edge and on the other side by a non-cutting edge and are configured to cut into the fastener when the bit is rotated in a direction opposite to the fastener's direction of engagement. Specific embodiments include configurations where the cutting edges extend at different angles with respect to the bit axis, where the biting surfaces comprise a plurality of serrations, and where the cutting edges are separated by flutes which spiral along a longitudinally extending periphery of the bit.
Claims18
A bit for removing a fastener from a work piece, said bit comprising:
- a) an elongated shaft with a longitudinal axis, said shaft having a first end, and a second end, said first end terminating in a tip and said second end of the shaft configured to be received by a tool which provides rotational torque;
- b) a plurality of non-cutting edges and a plurality of cutting edges, each of the non-cutting edges and cutting edges extending continuously from said tip to a bit periphery, said cutting edges configured to cut into a fastener when the bit is rotated in a direction opposite to an engagement direction of the fastener, and said cutting edges and said non-cutting edges alternating with each-other;
- c) a plurality of traction surfaces to grip the fastener, each traction surface extending from a respective one of the plurality of cutting edges and defining a first surface angle to the longitudinal axis and wherein at least one traction surface comprises a plurality of lineal serrations that extend across at least a portion of the at least one traction surface;
- and
- d) a plurality of relief surfaces extending between a respective one of the plurality of traction surfaces and a respective one of the plurality of non-cutting edges, each relief surface defining a second surface angle to the longitudinal axis which is different than the first surface angle.
Dependencies are inferred from the claim text.