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:
Jan. 14, 1997
Filed:
May. 08, 1995
Hiroyoshi Suzuki, Himeji, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A fuel mixing ratio detecting device can detect a fuel mixing ratio of a mixed fuel with high precision, regardless of the value of an electric conductivity of the fuel. The device comprises a sensor portion (an LC resonance circuit) having an electrostatic capacity detecting portion for detecting an electrostatic capacity of the fuel, which fills a space between electrodes, and a coil connected in parallel with the electrostatic capacity detecting portion, a voltage-controlled oscillator for generating a high-frequency signal having a predetermined frequency by performing a voltage control operation, a phase comparator for detecting a phase difference between a voltage and a current of the high-frequency signal applied to the sensor portion A, a target value switching unit for changing a phase difference target value between a first target value of 0.degree. and a second target value other than 0.degree., a control unit for controlling the voltage control operation of the voltage-controlled oscillator according to a difference between the phase difference detected by the phase comparator and the set target value, and a computing unit for computing a dielectric constant of the fuel from the frequency of the high-frequency signal when the phase difference has the first target value and for computing the electric conductivity of the fuel from an amount of shift between the frequency of a first high-frequency signal when the phase difference has the first target value and the frequency of a second high-frequency signal when the phase difference has the second target value and for detecting the mixing ratio of the fuel from the computed dielectric constant and the computed electric conductivity.