| 摘要 |
PURPOSE:To decrease deformation, ununiformity, etc. in a heater leg part and obtain a heater of high quality under a stable condition of welding, by processing a primary coil, in which a heating wire is wound to a core wire, to form a secondary coil, forming an insulating film to the secondary coil, securing said secondary coil to a supporting body, and then immersing the coil in a solution to dissolve the core wire. CONSTITUTION:For instance, an Mo wire of 5.0MG and a W wire of 8.0MG containing 0.3 Re are used for a core wire to form a closely pitched part, and a rough pitched part is formed to both ends of the closely pitched part, then a primary coil is formed. Then the primary coil is processed to form a secondary coil having a main heating part 1a and a leg part 1b. While alumina powder containing a binding agent is coated from a heater point end by the method of spraying or the like, and alumina is heated and sintered in hydrogen at increased temperature. Then the leg part 1b is welded to a supporting body 2 of stainless steel or the like, and the coil welding a heater main unit to a heater supporting body is immersed in mixed acid then the Mo core wire is dissolved. |
