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:
Aug. 18, 1987
Filed:
Dec. 23, 1985
Durham S McCauley, Boston, NY (US);
Miller G McCalmon, Orchard Park, NY (US);
McGard, Inc., Buffalo, NY (US);
Abstract
A tamper-proof bolt including a shank with a threaded end portion merging into an unthreaded portion of lesser diameter merging into an enlarged unthreaded portion merging into the larger base of a frustoconical head also having a smaller base, an undulating curvilinear groove in the smaller base, an island having lobes within the groove, an outer side in the groove, an inner side in the groove formed by the sides of the lobes of the island, and a cylindrical boss on the island extending axially outwardly from the smaller base and having a radial dimension which is approximately equal to the minimum radial dimension of the undulating groove. A key having an undulating curvilinear ridge for reception in complementary mating engagement in the curvilinear undulating groove of the bolt and having portions of a minimum radial dimension of approximately the same size as the boss for rotating engagement relative thereto and having lobes for meshing engagement with the sides of the undulating curvilinar groove when it is received therein.