| 摘要 |
PURPOSE:To prevent the damage of engine by detecting the temperatures of an internal combustion engine and by halting the operation of an ignition circuit during overheating. CONSTITUTION:A thermal detector 30 is designed to operate when the engine is overheated. As a minute current flows into a transistor 98 through a main switch 90 and a buzzer 92 in normal operation, the transistor 98 is on, and a thyristor 96 remains to be off. Therefore, the ignition circuit operates. As the base current for the transistor 98 flows into an earth through the switch 30 for the thermal detector during overheating, the transistor 98 is turned off. As the thyristor 96 is turned on by the current flowing through resistors 100 and 102, an generating coil 60 is shorted. Therefore, the ignition circuit stops operating. With this construction, the ignition circuit stops operating during overheating, which can prevent the damage of engine. The overheating conditions can be also detected from the buzzer 92. |
