| 摘要 |
<p>PURPOSE:To prevent the occurrence of an arc when a switch is opened by making a series circuit of a commutating condenser and the flywheel diode of a driving motor as the flywheel circuit of an electric device mounted on a car. CONSTITUTION:When a start instruction is given to control circuit 12, an electromagnetic switch 10 is actuated and power is supplied to electric apparatus 11, such as a power steering motor. Next, when switch 6 or 7 is switched to the side of the mornally open contact and this is detected by control circuit 12 via diode 8 or 9, a gate signal is sent from control circuit 12 to a chopper 2 and the driving motor 3 is driven. When a car stop signal is given to control circuit 12, the chopper 2 is cut off, and then the electromagnetic switch is opened and the control circuit is stopped. Further, at this time, if the communicating condenser 2a is being charged in the polarity shown in the drawing, discharging takes place through current transformer 23, diode 2b, flywheel diode 4 used for the driving motor, and the power steering motor 11.</p> |
