| 摘要 |
PURPOSE:To keep the precision near zero differential pressure value, by setting zero differential pressure on condition that an ignition switch is closed and an engine is stopped completely and holding it until the next running and correcting zero pressure each time when the engine is stopped. CONSTITUTION:A signal pulse RS is connected to a comparator RD for the number of revolutions, and the high-level output is generated from the time when the engine enters the stop state. This output is connected to an input terminal Gin1 of a gate G, and the signal from an ignition switch IGsw is connected to an output terminal Gin2 of the gate G. The output terminal of the gate G is connected to an instruction input terminal of a sample holding circuit S & H and a delay circuit R2C2 of an auxiliary power supply circuit. The signal from a differential pressure sensor 10 is connected to the non-inverted input terminal of a differential amplifier AMP, and the held value of a sample and holding circuit S & H is connected to the inverted input terminal of the amplifier AMP, and the amplifier AMP outputs a differential voltage e2=e1-e0 between an output e1 of the differential pressure sensor 10 and the held value. |
