| 摘要 |
PURPOSE:To enable a minimum amount of discharged air of a blower to be kept for maintaining a combustion characteristic by a method wherein a supervising means for performing a control over voltage or current to not less than a specified voltage or current is provided in addition to a control over the number of rotations of an air blower in case that a strong wind from an external part is attained. CONSTITUTION:In case that a controlling operation is carried out for keeping a specified number of rotations 15 of an air blower, a current 16 of an air blower motor is decreased as an air speed of air from external area is increased so as to keep the number of rotations of the air blower constant, so that an amount of air 17 discharged from the blower actually is decreased gradually. In view of a combustion performance of an equipment, a lower current limit value 19 of the air blower motor is calculated experimentally from an amount of air 18 of the air blower required minimum, and then a current supervising means 14 may supervise whether the current 16 of the air blower motor is less than this value 19 or not. If the current 16 of the blower motor is less than the current lower limit value 19, the current 16 of the blower motor is kept at the current lower limit value 19 without having any relation with the number of revolutions of the blower. At this time, the actual number of revolutions 15 of the blower is increased and the amount of air 17 of the blower can keep a required minimum amount of air 18. |
