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:
Feb. 17, 1987
Filed:
May. 22, 1984
Applicant:
Inventors:
Kevin Flynn, Brighton, MA (US);
Eric V Schultz, Cambridge, MA (US);
Assignee:
American District Telegraph Company, New York, NY (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G04F / ; H03K / ; G08B / ; G04B / ;
U.S. Cl.
CPC ...
364569 ; 34082531 ; 34030915 ; 328 63 ; 368200 ; 377 16 ;
Abstract
A card reader located in proximity to the central point of the secured area having a crystal controlled time base clock. Entry is granted when the proper information is entered to the card reader through a keypad or identification card. The clock is adjusted under software control according to a selected offset signal. The card reader is operable to provide access control of a secured area according to a schedule operable relative to the card reader clock without external reference signals.