| 摘要 |
PURPOSE:To reduce the charging power and protect oscillating transistors against damage by detecting the discharging voltage of a condenser for stopping the oscillation of a DC-DC converter at a set value and delaying the starting of oscillation until the completion of discharging. CONSTITUTION:A transistor 31 is connected with some delay after the start of charging of a condenser 30, and the base potential of a control transistor 2 is lowered for connection. Source power is supplied to a DC-DC converter 1 to start oscillation, and a condenser 4 is charged. By the completion of charging on the basis of the output transition of a comparison circuit 27 by the divided charging voltages by resistances 22 and 23 and divided voltages set by source power voltages 24 and 25, both transistor are disconnected, and the source power supply to the converter 1 is intercepted to stop the oscillation. When a contact 21 is opened, a thyristor 9 is connected by the pulse from a trigger circuit 20, and the charge of the condenser 4 is discharged to the primary coil of an ignition coil 5. When the discharging is completed, the output of the comparison circuit 27 is restored, and the above-written process of source power supply is restarted. |
