AIRBAG DEVICE

The present invention provides an air bag apparatus in which an amount of a gas flowing into an air bag can be adjusted in a stepless manner. A pinion 40 is rotated by activating a motor 38 according to an instruction from a control circuit to move a rack 34 straight in a desired direction. By this operation, an amount of a gas flowing into an air bag 14 is adjusted by opening/closing a gas ejecting port 30 provided in a module case 12.