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:
Jul. 31, 1984
Filed:
Dec. 01, 1983
Brian D Tucker, Ilford, GB;
Gould Advance Limited, Hainault, GB;
Abstract
Drift in the zero or datum reference point of a circuit (such as that forming part of a measuring device) is corrected by sensing the rate of change of the signal provided by the circuit and distinguishing between a rate of change characteristic of that due to a valid signal indicative of a measurement and a rate of change characteristic of that due to drift in the circuit. In one embodiment, a window comparator 18 senses the rate of change of the signal output from circuit 10 by periodically sampling in sample/ hold 16 and then comparing with the current value of the signal. A signal circulating path 20, 21, 22 holds a drift compensating value which is updated when comparator 18 senses a rate of change below a threshold value which is indicative of drift in circuit 10. The drift compensating value is added to the signal from circuit 10 in summing amplifier 15 thereby correcting the signal for drift.