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. 25, 1989
Filed:
Jan. 16, 1987
Applicant:
Inventor:
Richard L Bireley, San Diego, CA (US);
Assignee:
Aquametrics, Inc., San Diego, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
F16K / ;
U.S. Cl.
CPC ...
137 783 ; 324 / ; 324 / ; 324 / ; 361178 ; 361181 ;
Abstract
A monitor or sensor for sensing the moisture content of a surrounding medium comprises two electrodes connected in a detector circuit for detecting the impedance between them and producing an output signal proportional to the impedance. At least one of the electrodes is covered by a dielectric coating and the other electrode is positioned to minimize any capacitative effects between the electrodes through the surrounding medium. The detector may comprise a multivibrator with an output frequency controlled by the sensor impedance, and the output signal can be used to control the operation of watering equipment.