To maintain initial response of an actuator even if hysteresis width of the actuator 2 gets wider due to aged deterioration of the actuator 2.
A dither width establishing means 61 increases dither width of dither current based on load information and operation time of an engine. Namely, the dither width establishing means 61 increases dither width of dither current by increasing pulse width of dither signal based on the load information and the operation time of the engine. The dither width establishing means 61 includes a pulse width storage means storing a relation between pulse width and the load information and the operation time of the engine, and establishes pulse width corresponding to the load information and the operation time of the engine as pulse width of the signal.
FUJII YASUO
YAMA HAJIME
Toshiyuki Kimura
Next Patent: AUXILIARY CHAMBER TYPE ENGINE