| 摘要 |
<p>A step motor controller is disclosed, in which in order to control the rotor accurately according to the degree of a step-out, if any, of a step motor (26), the step motor (26) is driven in accordance with a control signal generated based on the present position and a target position, the difference between the true position associated with the actual position of the step motor (26) and the present position thereof is detected, and the control signal is corrected in accordance with the difference. Further, in the case where the step motor (26) used for driving an intake throttle valve (25) of an internal combustion engine (11) steps out, the internal combustion engine can be driven without emitting a smoke, and the criteria for judging a step-out can be changed in accordance with whether the step-out is to an opening side or a closing side. For this purpose, upon detection of a step-out of at least a predetermined degree, the step motor (26) is controlled to a predetermined high opening position. The step motor (26) is judged to have stepped out, in the case where the actual position is displaced to the opening side by at least a predetermined first value from a target position or in the case where the actual position is displaced to the closing side by at least a second predetermined value from a target position. The first predetermined value is set larger than the second predetermined value. <IMAGE></p> |
