Screwdriver bit attachment sleeve for screw centring and holding - comprises left hand wound coil spring which acts both in compression and extension

摘要

The sleeve fitted to the shank of a screwdriver is spring-loaded and effective both axially and radially. It requires no mechanical aid but works entirely independently. The sleeve (8) is in the form of a left hand wound coil spring which works both as compression (8c) and tensile spring(8b). The tensile spring is covered on its end by a sleeve with its bottom edge turned inwards over the spring. ADVANTAGE - Simple,low-cost,effective design.