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:
Dec. 18, 1984
Filed:
Jun. 03, 1982
Norikazu Sawazaki, Yokohama, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
An electrostatic voltage detecting device includes a detecting electrode for detecting an electrostatic voltage generated by charge on a recording medium, a variable capacitance diode whose capacitance changes according to an output signal applied from the detecting electrode, a primary coil combined with the variable capacitance diode to form a resonance circuit, an oscillator for supplying an oscillating output signal of predetermined frequency to the primary coil, and a secondary coil inductively coupled with the primary coil. The capacitance of the variable capacitance diode changes according to an output voltage applied from the detecting electrode to vary a resonance frequency of the resonance circuit and consequently a voltage induced in the secondary coil.