| 摘要 |
PURPOSE:To prevent erroneous operations, by comparing the output signal of an acceleration sensor for a vehicle with a specified threshold value, outputting ON/OFF signals, operating a safety apparatus when the accumulated values of the elapsed times of the ON signals exceeds a specified value, thereby operating the apparatus quickly even at the time of low speed running. CONSTITUTION:An acceleration sensor 1 converts acceleration developed in a vehicle into an electric signal and outputs the signal. The outputted acceleration signal is amplified in a differential amplifier 2 and sent to a first comparator 4 through an LPF 3. The comparator 4 compares the acceleration signal with a threshold value. When the acceleration signal exceeds the threshold value as a result of comparison, an ON signal is outputted to a timer 5. The timer 5 measures the duration of the ON signal and outputs the result to a second comparator 6. The comparator 6 accumulates the durations of the ON signal and compares the accumulated time with a threshold value. When the accumulated time exceeds the threshold value, an ON signal is outputted to a trigger device 7 and a safety apparatus is operated. In this way, the apparatus is operated relatively quickly even at the time of low speed running, and the occurrence of erroneous operations can be reduced. |
