| 摘要 |
PURPOSE:To attempt rapid red-heating of the tip of a heater and control its peak temperature and saturation temperature appropriately by constituting as one body a heat generating section consisting of conductive ceramic material and a control section with different positive resistance temperature coefficients and exposing the heat generating section to the surface of the heater. CONSTITUTION:A heat generating section 20 is exposed to the outer surface of a heater 11 and a control section 21 is incorporated in the heat generating section. A voltage is applied from an outer connection terminal 14 via a metallic wire 16 and an electrode 15 to the heat generating section of the heater 11 and a control section 21. Then, the voltage is divided among the heat generating section 20 and the control section 21 in proportion to their ratio of electric resistance, applying a larger voltage to the heat generating section 20 than to the control section 21. Accord ingly the heat generating section 20 has a larger electric power density relative to the control section, making the heat generating section 20 at the tip of the heater 11 generate heat rapidly. As the side of the control section 21 generates heat, its resistance increases, changing the voltage applied to the heat generating section 20 and the control section 21, and the application of voltage to the heat generating section is thereby controlled and its temperature is saturated at about 850 deg.C after it has reached the peak temperature of about 1,200 deg.C. Its overheating can be, therefore, avoided. |
