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US 4,285,255 AGranted
Safety screwdriver
OwnerCarl T. Winfreyinventor
Life of this patent
Estimating the term…
Abstract
A safety screwdriver having a handle and a shank portion which includes an axially extending tubular extension surrounding a substantially rectangular blade recessed within. In the preferred embodiment the blade and tubular extension are a unitary construction with opposite side edges of the blade integrally cast to the side walls of the tube.
Claims3
The combination of a driver and slot head fastener comprising:
- (a) a driver including an elongated shank portion having a handle secured to one end in axial alignment therewith and a hollow tubular extension in axial alignment thereto at the end opposite said handle;
- (b) said slot head fastener having a threaded shank and a head of a prescribed thickness secured to one end of said shank, said head having a slot defined in the upper surface thereof, said slot extending a prescribed depth into and transversely of said head;
- (c) said tubular extension of said driver including an elongated flat blade positioned therein such that the terminal edge of said blade is recessed a prescribed distance within said tubular extension;
- (d) said prescribed distance of said blade recession being so related to the thickness of said fastener head and the depth of said slot that when said blade is positioned in said slot, said tubular member substantially encases said fastener head with the terminal edge of said tubular member positioned in a plane parallel to and intermediate of the upper and lower surfaces of said fastener head;
- (e) whereby said tubular member remains clear of the surface into which said fastener is being inserted.
2 more elements
Dependencies are inferred from the claim text.