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:
Nov. 09, 1982
Filed:
May. 01, 1979
Ernest C Wittke, West Caldwell, NJ (US);
The Singer Company, Little Falls, NJ (US);
Abstract
An absolute digital clock system which is capable of counting absolute time despite the disruptive effects of a nuclear event, or other disturbance, on the electronic circuitry of the system. The clock system of the invention includes a master quartz crystal oscillator stage, and a string of counter stages connected thereto each including a binary counter for counting down from the frequency of the preceding stage to a lower frequency, and each including a crystal oscillator phase-locked with the binary counter and producing a signal at the lower frequency. During the period of time when the radiation level is too high for adequate electronic functioning, the quartz crystals in the master stage and subsequent counter stages continue to vibrate without significant loss of phase information due to the high mechanical inertia of the quartz crystals, and this mechanical inertia of the various crystals is used in the system of the invention to enable the system to continue to indicate absolute time despite an interruption of substantial length as compared with the period of vibration of the individual crystals.