| 摘要 |
PURPOSE:To prevent over-rotation of engine accurately by connecting a time constant circuit to the gate of an ignition thyristor and holding the thyristor under conductive condition through said circuit until generation of an output in positive direction upon increase of engine rotation. CONSTITUTION:An exciting coil 20 for a magnet generator is connected through a diode 21 to a charging/discharging capacitor 22 while the primary coil 24 of an ignition coil 23 is connected in series with said capacitor 22. Furthermore, an ignition thyristor 29 is connected in series with said capacitor 22 and a diode 30 is connected in parallel with said thyristor 29. Then a time constant circuit 34 comprised of an electrolytic capacitor 32 and a variable resistor 33 is connected through a resistor 31 to the gate of said thyristor 29 and a signal coil 36 is connected through a diode 35 to said circuit 34. The signal coil 36 is shared with said coil 20 and formed by grounding the coil 20 at the center tap. |
