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Figure 1 is an outside view, and figure 2 is a longitudinal section of the Jaw Screw Dri- ver.invented bv Jacob W. Switzer, of Basil, Fairfield Co., Ohio, who has taken measures to secure a patent therefor. This screw driver is operated like the stock-brace, onlyit has spring jaws for holding the head of the screw-nail, while the driver is inserted into the groove or notch in the head of the nail. The handle of the stock is broken off. A is part of the handle, and B is the stock; j they are made in-the usual manner ; D is the shank of the driver, E. F F are spring jaws forembracing the head of the screw-nail. C is a barrel or tube surrounding the shank of the driver, and legs of the spring ja ws, F F. The spring jaws are fastened to the shank of the driver l-*Wth*4-.lplM'giia slot, G, m sails' s.ak, this slot allows the driver to be thrust further out beyond the face of the jaws, or to be drawn within them. This operation is performed by having a right-handed thread cut on theshank, D, and a left-handed thread; a, cut on the insi'de of the barrel, C, as shown in fig. 2. To drive in a screw-nail, the jaws are made to embrace the head of the nail, and are compressed on to them by turning the barrel, C, to the right, the driver then being, as represented, inserted into the crease of the nail head. By turningthe stock, thebarrel, C, and driver, revolving to the right, the screw is driven in rapidly and with great ease; no hole is required to be made with a gimblet,pre-vious to driving in the screw. To release the jaws from the head of the screw, all thatis necessary to be done is simply to graspthe barrel, C, firmly with theleft hand and keep turning in the same direction The slot, G, allows the driver to be forced be-; yond the jaws, when the barrel is grasped, and this relieves them. To draw a screw from a counter-sink, the driver, E, is worked- to project beyond the jaws (which is done by holdingon to thebar rel.with theleft hand and turning with the right),and then it is. inserted into the crease of the head of the screw, and the stock is turned to the left, the barrel turning round with the driver. After the head is drawn out a short distance, the barreJ, C, is held firm with the left hand, and the jaws are then left free, and allowed to grasp the head of the nail when this is done, the barrel, C, is turned round with the left hand, to bring it down firm on the jaws, after which the'driver, jSws, and barrel are turned to theleft,and thescrew is drawn out rapidly. More information may be obtained by let ter addressed to the inventor.
