Coating machines having a coating material discharger configured to discharge a coating
material under pressure to an atomizer wherein a coating material bag for filling the coating material is housed in a coating material discharging chamber of a predetermined volume, and an inlet/exit port of an operating fluid is disposed in the material discharging chamber for exerting a pressure from outside of the coating material bag thereby discharging the coating material under pressure; wherein plural coating material bags are provided in the coating material discharging chamber, and switching valves are interposed in coating material discharge flow channels from each of the coating material bags to the atomizer to selectively supply the coating material from one of the coating material bags to the atomizer during entering of the operating fluid.