Driver bit attachment

Claim 1

An attachment for a power tool to permit driving of threaded fasteners said attachment comprising a generally cylindrical body; projection means extending from one end of said body, said projection means being adapted for connection to said power tool to receive rotational torque therefrom; a first longitudinal bore extending axially within said body; a driver bit having a portion which is received within said first bore; securing means within said first bore for retaining the driver bit therein; a second bore which has a larger mean diameter than said first bore, said second bore extending from said first bore to the end opposite the end having the projection, said second bore having an axial length approximately equal to the height of the fastener head with which the adaptor is to be used and a mean diameter larger than the maximum width dimension of the fastener head, a portion of said driver bit being received therein; a set screw threadingly engaged in a tapped hole in the the projecting means and extending into said first bore from said projection means end to position the driver bit within the first and second bores so that the point of disengagement of the driver bit from the fastener head may be varied in order to prevent over torquing of the fastener.