| 摘要 |
PURPOSE:To improve the temperature rising efficiency and obtain a heating unit with excellent electric insulation property, heat resistance and heat insulation property by aligning many positive-characteristic thermistor plates, pinching them with a pair of ceramic frames, and allowing the feed air to pass only between the thermistor plates. CONSTITUTION:The first frame 6 with excellent electric insulation property, heat resistance and heat insulation property and made of ceramic is fitted to the second frame 7. The first PTC heater 2a and the second PTC heater 26 are pinched with some degree of freedom in the vertical direction between the frames 6 and 7. The heating unit 2 thus assembled is assembled to a blast duct. It can be assembled simply with a low cost, and a hot air heater with very excellent airtightness, electric insulation property, heat resistance and heat insulation property can be constituted. The heat of the heater is not transferred to the blast duct fixing the heating unit 2, thus a resin material or the like with low heat resistance can be used, and the whole hot air heater can be constituted lightweight with a low cost. |
