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:
Sep. 15, 1981
Filed:
Aug. 13, 1979
Anker J Nielsen, Jr, Holden, MA (US);
Omco, Inc., Holden, MA (US);
Abstract
A conventional tubular lock is made pick-resistant by the inclusion of a specially designed washer. The washer, which has a non-circular opening, is provided in the lock interior. The washer is preferably located between the helical compression spring and the rear face of the slidable plunger. The opening in the washer permits the insertion of a specially shaped expandable key, but does not permit the insertion of an old style expandable key, or a nail or other similarly round picking tool which has a sufficiently large diameter to wedge in the rear bore of the plunger. Therefore, the specially designed washer permits the lock to be opened only by an authorized key, but not by a nail or an unauthorized key.