초록

The present disclosure relates to a device designed for use in surgical procedures requiring the driving of screws into bone. The device provides positive locking screw holding engagement yet permits angular movement of the screw of up to 10°from the axial direction.

대표청구항 ▼

In combination, a screw driving bit having a rearward driving end, a shank and a forward screw engaging end and a screw retaining device movably attached to the shank of said bit, said screw retaining device comprising a collet and a plurality of screw retaining balls disposed within openings equidi

In combination, a screw driving bit having a rearward driving end, a shank and a forward screw engaging end and a screw retaining device movably attached to the shank of said bit, said screw retaining device comprising a collet and a plurality of screw retaining balls disposed within openings equidistantly spaced around the periphery of said collet, said balls being frEe to move radially in said openings, a spring biased member which, in a first position, biases said balls radially outwardly and which, in a second position, exerts spring pressure against the head of a screw received within said collet, a spring biased collet sleeve which, in a first position, restrains the outward movement of said radially outwardly biased balls and which, in a second position, biases said balls radially inwardly against the shank of said screw thus preventing axial movement of said screw, spring means biasing said screw driving bit into a forward position into engagement with the slot in said screw head thereby further preventing axial movement of said screw and eliminating marring of the screw head in the screw driving process.