The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 1980
Filed:
Jul. 26, 1978
Applicant:
Inventor:
Charles E Gutshall, Rockford, IL (US);
Assignee:
Technofast, Inc., Willowbrook, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16B / ;
U.S. Cl.
CPC ...
85 45 ;
Abstract
A screw head recess includes a generally frusto-conical central socket and radial slots interconnected by concave sections of the socket. Each slot is defined by two opposed wall surfaces which intersect with a bottom surface which slopes radially inwardly and downwardly along the axis of the screw. At least a portion of the junction between one sidewall and the bottom surface is curved to produce a camming surface for frictional engagement between the screw and a driving tool sufficient to provide a temporary stick-fit between the screw and the tool.