摘要 |
A heat treating apparatus utilizes a straightening plate provided in its central part with a gas exhaust opening and disposed under a heating plate. A temperature-reducing purge ring is disposed between the face plate and the straightening plate, and is provided in its inner circumference with plural gas jetting holes. A thin gap is formed between the temperature-reducing purge ring and the face plate. When a cooling gas is jetted radially inward through the gas jetting holes, a vacuum is created between the lower surface of the face plate and the upper surface of the temperature-reducing purge ring. Air is sucked into the space between the face plate and the straightening plate and flows together with the cooling gas to rapidly cool the face plate. |