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:
Dec. 03, 1996
Filed:
Apr. 17, 1995
Yasuo Suzuki, Saitama, JP;
Kabushiki Kaisha Suzuki Rashi Seisakusho, Saitama, JP;
Abstract
A fastening screw is provided with a locking function to prevent loosening thereof after being tightened. In one aspect of the invention, the fastening screw has a head having a bearing face; a plurality of convex portions and concave portions formed on the bearing face to provide shallow wavelike portions proceeding in a circumferential direction of the bearing face; and a thread portion having a flat top portion, the width of the flat portion being larger than that of a root of a thread portion of an internal thread, wherein the angle between a slant surface of the fastening screw on a screw-tightening side and a line vertical to an axis of the fastening screw is substantially equal to the angle between a slant surface of the internal thread on a screw-loosening side and the line vertical to the axis of the fastening screw, and the angle between a slant surface of the fastening screw on the screw-loosening side and the vertical line is smaller than the angle between the slant surface of the fastening screw on the screw-tightening side and the vertical line.