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:
Jun. 14, 1977
Filed:
Jan. 21, 1974
Applicant:
Inventors:
Minoru Tanaka, Yokohama, JA;
Shoichi Mitani, Yokohama, JA;
Takeo Yuminaka, Katsuta, JA;
Rokuro Sasaki, Katsuta, JA;
Hatuya Nakamura, Katsuta, JA;
Assignee:
Hitachi, Ltd., , JA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01V / ;
U.S. Cl.
CPC ...
328-5 ; 307308 ; 3402 / ; 331 65 ;
Abstract
A compact and low-cost apparatus for detecting the proximity of a human body and generating a corresponding electrical signal is disclosed which apparatus includes an oscillator and an operational amplifier. Under normal conditions, equal input voltages are applied to the input terminals of the operational amplifier, whereas the equilibrium of the input voltages is lost by the approach of a human body to the apparatus.