| 摘要 |
PURPOSE:To enable stable and accurate measurement by varying the band-pass characteristic of a variable filter circuit according to the operating condition of the engine to remove a pulsating wave component mixed the measuring pressure. CONSTITUTION:A detection means 7 for detecting the operating condition of the engine uses a piezo-electric element provided on the engine box. A pulsating signal varying according to the operating condition of the engine is obtained therefrom and applied to a control end of a frequency variable filter circuit 6. A signal from the variable filter circuit 6 is inputted into a measuring circuit 8 to obtain a pressure signal by performing a specified computation. |
