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:
Aug. 04, 1981
Filed:
May. 01, 1979
Katsuyuki Fujito, Kadoma, JP;
Seiro Hasegawa, Kadoma, JP;
Takehiko Unoguchi, Kadoma, JP;
Atsushi Nishino, Kadoma, JP;
Akihiko Yoshida, Kadoma, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
Apparatus for humidity detection comprises a humidity sensing element, the electrostatic capacitance of which varies in accordance with the ambient humidity, a fixed capacitor, first and second pulse generating circuits respectively responsive to the sensing element and the capacitor, and a computing circuit responsive to pulses from the first and second pulse generating circuit. The sensing element and the fixed capacitor are respectively charged via resistors to produce first and second pulses in accordance with voltage across the sensing element and the capacitor. The difference between the widths of the first and second pulses is detected in the computing circuit to produce an output pulse indicative of the relative humidity, thereby compensating for undesirable infuenece due to dielectric loss in the sensing element so as to accurately measure humidity irrespectively of the ambient temperature.