Fastener driving tool

Claim 1

For use in combination with an actuator base including: engaging means for securing a working head thereto, reciprocal hammer means driven in response to an energy source, and activating means for selectively energizing said hammer, an improved working head for first holding a fastener having a head and a bifurcated shank in alignment with said hammer and then guiding said fastener as said fastener is forcibly discharged therefrom by said hammer whereby the prongs of said bifurcated shank enter a preselected material in controlled deformed relationship, said improved working head comprising: a. an elongate base having an upper end adapted to be secured to said activator base and a lower end for abutting said preselected material; b. a pair of fixed guides upstanding from the face of said base and extending longitudinally from the upper end along a substantial portion of the length thereof, said fixed guides being in parallel arrangement and having a distance therebetween corresponding to the distance across the head of said fastener and having a height relative the material thickness of said fastener; c. a pair of opposed movable guides disposed below said fixed guides; d. biasing means for normally urging said movable guides inwardly to contact the shank of said fastener and permitting retraction of said movable guide for passage of said head therebetween; e. a cover plate secured to the face of said base, disposed upon said fixed guides and terminating proximate the movable guides and having an aperture therein sized and shaped for insertion of said fastener; and f. an anvil proximate the lower end of said base in the discharge path of said fastener for controllably deforming the prongs of said fastener.