| 摘要 |
PURPOSE:To minimize the consumption of power at the time of ignition and to extend the life of the ignition device by a method wherein the operation time of the ignition device is controlled in proportion to the variation of the ambient temperature. CONSTITUTION:When the ambient temperature is high, the resistance of a thermister 7 becomes small and the conversion voltage increases. Then, the increased conversion voltage is reversed and amplified by an operation amplifier 6 and the threshold voltage level of a timer 5 is set at a low value. The timer 5 is formed of a CR circuit and a programable unijunction transistor (PUT) and the CR circuit is connected to the anode of the PUT while the output of a timer control circuit 6 (the operation amplifier) is connected to the gate of the PUT. In this case, a capacitor C of the CR circuit is charged with a predetermined time constant so that when the potential at the PUT goes low, the time set on the timer 5 becomes short. On the other hand, when the ambient temperature is low, the resistance of the thermister becomes large and as a result, the time set on the timer 5 becomes long. Consequently, it is possible to reduce the consumption of power at the time of ignition and to extend the life of the ignition device. |
