| 摘要 |
PROBLEM TO BE SOLVED: To suitable restrain the occurrence of stepping-out the like due to the reduction in the driving voltage of a step motor in controlling the step motor type valve device. SOLUTION: An intake throttle valve 4 arranged inside an intake passage 2 is driven by a step number control making a reference of a prescribed step position of a step motor 40. When the voltage of a battery to be supplied to the step motor 40 decreases below a prescribed voltage, an electric control device 19 set the target opening value of the intake throttle valve 4 to a value, for instance, corresponding to the full-open position of the same intake throttle valve 4. |
