To pursue compression of processing time in a conventional vacuum furnace, accurate quality control, optimization of a totalized control mainly intended for energy saving, and improvement of productivity.
A partition plate 3 surrounding a heated object while leaving a certain part opened, and a heater 4 positioned between an inner furnace wall and the partition plate 3 are provided in the furnace. A fan 7 is provided for circulating and diffusing gas heated up by the heater 4 to heat up the heated object. Circulating the gas heated up by the heater 4 through the inside and the outside of the partition plate to diffuse the gas in the furnace makes the temperature distribution of the heated object uniform, remarkably reducing the time for heating up, which achieves energy saving in heating up.
FUJIOKA TOSHIO
AKAYAMA TAKASHI
Nozomi Tsujimoto
Ueno Yasunari