PURPOSE: To easily alter an air blowoff direction by arranging an air blowoff head having opening parts provided on the air supply side and air blowoff side thereof and having first and second set collars.

CONSTITUTION: An air supply port 11 has the first connection end connected to the air supply hose outside a first frame 14 and the second connection end fitted to the opening part on the air supply side of an air blowoff head inside the first frame 14 and the intermediate part thereof has a hollow structure. When temp. controlled air is supplied to the first connection end of the air supply port 11 from the air supply hose, it passes through the second connection end from the first connection end to be sent to the opening part on the air supply side of the air blowoff head. The air blowoff head 1 has a cylindrical shape and one end of the cylinder thereof becomes the opening part on the air supply side and the other end thereof is closed. The blown-out temp. controlled air is sprayed on an article 9 to be controlled in temp. to transmit heat thereto to heat the article 8.