| 摘要 |
PURPOSE:To enable the measurement of the content of alcohol in a fuel from the outside of a piping, by measuring the content of alcohol from the degree of attenuation of a microwave which is transmitted through waveguides to transmit through a fuel piping and is attenuated by this transmission. CONSTITUTION:A microwave delivered from an oscillator 5 reaches a converter 4a through a coaxial cable 6a and is emitted into a waveguide 3a from a coaxial inner conductor 61 of the cable 6a which is projected into the cavity of the converter 4a. While forming a wave electric field, this microwave is transmitted through the waveguide 3a and, traversing through a fuel piping 1 disposed midway, reaches a converter 4b through a waveguide 3b. The microwave transmitted to a coaxial cable 6b through the intermediary of the converter 4b is converted into a DC voltage proportional to the amplitude by a detector 7 and is sent as a sensor signal to an air-fuel ratio controlling device through a lead wire 7a. A sensor measures the degree of attenuation of the microwave which is attenuated in accordance with the content of alcohol in a mixture fuel and reaches the detector 7, and detects the content of alcohol accurately. |
