A microactuator reference limit used to prevent over-accumulation of internal states may be set based on the microactuator’s mechanical properties and is applied at the reference point to the microactuator servo subsystem. In the apparatus main body, there are stored a first duct for sucking in air from the open air, a resonator connected to the first duct, a cleaner for cleaning the sucked-in air, and a second duct 30 for sending out the air, after it has passed through the cleaner, into the internal combustion engine. 5 times the head diameter for easy use and the head is fitted with the various water filter sizes.