Screw guide for powered screwdriver - has geometry of lever holding screw on guide block chosen so that friction of screw applies moment forcing lever hard onto screw

摘要

The attachment fits on the front end of the powered screwdriver and is positioned so that the screw (5) is co-axial with and directly in front of the driving bit. On the frame (7) of the attachment is a fixed guide block (11) with a semi-circular recess (12) in which the screw rests. Pivoted on the frame is a lever (9) with an inclined surface (15) which presses down on the screw under pressure of a spring (13). When the screw is driven home the lever is pushed up against the spring pressure by the head as it seats in the work. ADVANTAGE - Tilting of screw is prevented. Only light spring pressure is required on lever.