| 摘要 |
PURPOSE:To ensure the ignition of a squib as well as to use an amount of limited electric power in an effective manner by stopping a power supply to an igniter from a power supply means if the size of an overcurrent detected by an overcurrent detecting means installed in a current supply line, comes to the specified value. CONSTITUTION:Two current detecting resistors 20 and 21 with a specified value of resistance each are connected to both grounding sides of squibs 13 and 12 in series, while both first and second overcurrent judging circuits 22 and 23 inputting the value of voltage to be generated at the nongrounding side, compre the electric potential, thereby varying the output into a high level as it is so judged that an overcurrent has flowed if the potential at the nongrounding side becomes larger as far as exceeding the reference potential. On the other hand, a microcomputer 26 selects the generating time of a trigger signal to be fed to two switching transistors 29 and 31, corresponding to the squib 12 or 13 where the over current flows, to a short time. With this transfer, such a possibility that it is one-sided to the one squib due to the overcurrent and thereby feeding is carried out of a backup condenser 5 is thus prevented from occurring. |
