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. 12, 1989
Filed:
Jan. 27, 1989
Philip D Barrett, Salem, OR (US);
Walter G Henderson, Salem, OR (US);
Wayne F Larson, Salem, OR (US);
Supra Products, Inc., Salem, OR (US);
Abstract
An electronic lock system is provided with a 'lockout list' that identifies keys that are to be prevented from opening system locks. Date coded lockout lists are carried in the memories of both the system's locks and keys. When a lock and key engage, the date codes of the lock and key lists are compared to determine which list is that most up-to-date. This list is then transferred into the other unit, overwirting that unit's stale list. Subsequent interactions of either of these units with other locks and keys will further spread the most timely lockout list data. By this arrangement, new lockout lists can be disseminated throughout a lock system simply by loading them into one or more keys. As these keys are used with locks, and those locks used with other keys, the list will spread throughout the system. A variety of other operational features are also disclosed.