GB133129A - - Google Patents

Abstract

133,129. Mackay, R. A., and Adam, Grimaldi, & Co. Sept. 25, 1918. No Patent granted (Sealing fee not paid) Screwdrivers. - A screw-driving attachment for a brace or a drilling or other machine comprises a frame slidable on the screwdriving bit and carrying a screw hopper and spring-controlled jaws for holding the screws during the driving operation, the feeding of the screws from the hopper being effected automatically by the relative movements of the frame and the bit. The hopper d is carried by a sleeve b of a frame a supported by a rod h' from a bracket l secured to the brace or machine. The sleeve b slides on the bit c and is normally pressed towards its free end by a spring h on the rod h'. The sleeve b is provided with a pair of spring-pressed jaws q to hold the screw while it is being driven and until it is nearly home, when the jaws are pressed apart by the head of the screw engaging the inclined internal faces of the jaws. The lowermost screw in the hopper is held by a detent f carried by a pivoted arm k, which is actuated to release the screw by a plunger i, which is operated by an enlargement c<2> on the bit during the driving of the previously-fed screw. The released screw falls into engagement with the side of the bit c until, when the bit is again raised, the screw falls into the jaws g. The depth to which the screws can be inserted is limited by the engagement of the enlargement c<2> with the end of the sleeve b, and the enlargement c<2> may be adjustable to suit screws of different lengths. A number of removable sleeves such as b of different diameters may be provided for use with screws of different sizes.