PURPOSE: To ensure that when a solenoid is re-driven, the energy originating in the preceding driving is completely discharged by the time of the subsequent driving, by a construction wherein a switching element for discharging through a rectifying element is provided, and an absorbing capacitor is provided between the switching element and the rectifying element.

CONSTITUTION: When ON signals SG15, SG12 are outputted to a power-supplying transistor Tr15 and a transistor Tr12 for driving a solenoid L12 in the condition wherein the energy in a solenoid L11 is not yet completely discharged, a driving current I12 starts to flow in the solenoid L12. At this time, since a discharging transistor Tr16 is turned OFF, the energy in the solenoid L11 is discharged through a discharging circuit consisting of a diode D11 → the absorbing capacitor C1 → a diode D17 → the transistor Tr15 → the solenoid L11. Accordingly, the attenuation time of a discharge current can be shortened, and the energy in the solenoid L11 is completely discharged by the time the subsequent driving of the solenoid L11 is started.