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:
Oct. 29, 1996
Filed:
Nov. 23, 1993
Yasuo Suzuki, Saitama, JP;
Kabushiki Kaisha Suzuki Rashi Seisakusho, Saitama, JP;
Abstract
The screw of this invention can be used for fastening members of a variety of materials and reliably prevent loosening of the screw. The screw shank is formed with two threads, a main thread for driving the screw and a sub-thread which extends in the same direction as the main thread, is smaller in outer diameter than the main thread and has a pitch different from the main thread. The inclination of the slant surface of the sub-thread is set steep on the loosening side and moderate on the fastening side. The pitch of the main thread is set larger than that of the sub-thread. When the tightened screw is applied a loosening torque, the sub-thread bites into the inner wall of the hole, preventing the screw from being loosened.