GB178160A - Improvements in and relating to screw-drivers - Google Patents

Abstract

178,160. Vianello, O. Dec. 8, 1920. Screwdrivers. - A screwdriver is provided with means for deforming the nick of the screw to prevent removal of the driver blade in an axial direction. The blade 4, Fig. 6, has an enlarged end 3 to engage the nick 1 of the screw and is mounted in a wood or metal sheath 7 to which is pivoted a pair of blades 8 drawn together by a spring 10 and adapted when the handle 5 is struck by a hammer to deform the central part of the edges of the nick 1, as shown in Fig. 4. The blade 4 is preferably in two parts connected by a pivot 60 so that after the actuation of the blades 8 the sheath 7 may be retracted to allow it and the upper part of the blade to be turned at right angles to the acting part 2 of the blade, to serve as a crank for turning the screw. A spring snap 12 engages either of two holes 14, 16 in the blade 4 according to whether the tool is used with the blade in the straight or turned dcwn position. Screw-engaging heads 3 may be provided on both end of the blade 4. The handle 5 is connected to the sheath by a clutch device which permits of a return movement of the handle independent of the sheath. This clutch comprises a sleeve 18 secured to the handle 5 and mounted upon the cylindrical part 19 of the sheath 7 and provided on its lower edge with notches. 2.0 held in engagement with projections 22 on the part 19 by a spring 21. In a second form, Fig. 10, the deforming blades 8 are secured to the handle 5 and are connected to the driver shank 2 by a thumb or other screw 6 and slot 27 which may contain a spring or other elastic body beneath the screw to raise the blades after deformation has been effected. A second spring device may also be arranged above the screw 6. The tool may be used with the blades 8 turned down as shown, or in line with the shank in which position they are retained by a spring catch engaging a slot 14 in the shank 2. A number of screw-driving blades of different sizes arranged in the form of a star may be pivoted to the shank 2, the screw 6 permitting of adjustment of the blades 8 according to the thickness of the individual driving blades. In the form shown in Fig. 11, the deforming blades 8, slidably mounted on the shank 2 by screws 6, 6<1> and slots 27, 27<1>, are connected by a block 31 and the handle shank 2<1> carries two similar plates 8<1> connected by a block 31<1> and the shank 2<1> is pivoted by pins 30 to the shank 2. The tool may be used with the shanks 2, 2<1> in line or at right angles, the deformation of the screws being effected by striking the block 31<1> or 31.