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. 23, 1985
Filed:
Aug. 29, 1983
Applicant:
Inventor:
David M Beams, Virden, IL (US);
Assignee:
Dickey-john Corporation, Auburn, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
340684 ; 56 102 ;
Abstract
A monitoring circuit is provided for a metal detector which includes a metal sensor for producing a sensor signal in response to the passage of a metallic object through a rotating apparatus and a tachometer for producing a tachometer signal at a frequency proportional to the rate of rotation of the rotating apparatus. In accordance with the invention, the monitoring circuit comprises an adjustable tracking filter responsive to a predetermined control signal for tracking the frequency of the sensor signal in a predetermined fashion and a control circuit responsive to the tachometer signal for producing the control signal.