VACUUM FURNACE

PURPOSE:To heat a work from a central part of a heating space also to permit heating to obtain an uniform temperature in a short period of time by a method wherein a plurality of heaters are provided around a space, in which the work to be processed is placed, and a heater is also arranged at the central part of the same space. CONSTITUTION:A central heater 27 is arranged at the central part of a space 11, in which a work is placed, and the work 25 to be processed is positioned in the space 11 under a condition that said central heater 27 is elevated. The work 25 is placed in a hollow part 34 at the center of the space, the, said heater 27, elevated already, is lower. Hearts 12a-12d, provided around the space 11, and the central heater 27 are excited to generate heat under this condition. In this condition, the work 25 to be precessed is heated from the outer periphery by the heaters 12a-12d and, simultaneously, is heated from the central part thereof by the central heater 27. As a result, the whole body of the work 25 is heated to a uniform temperature in a short period of time.