| 摘要 |
PURPOSE:To be able to continue long-life catalyst effect by decomposing oil surely with uniformity of filter temp. by a method wherein heat generating density of a heater heating the filter having oil-decomposing catalyst is made large at the filter peripheral parts except the upper part. CONSTITUTION:A heater has a heating element 22 buried in an insulator (mica plate) 21 and composed of an Fe-Cr electric wire, and spaces of the heating element 22 are so arranged as to be marrow, that is, close at peripheral parts of the left, right, and lower parts, and wide at the center and upper parts. At the time when necessary exhaust is finished at the end of cooking, a front shutter 17 is closed. In this state, heating is started by conduction of the heater 19. A timer is energized accompanied with electricity flow the heater 19 and the timer is deenergized after necessary time for decomposing oil elapsed, and conduction of the heater 19 is stopped. Thus, as the heater 19 has narrow spaces, that is, a large heat generating density at the peripheral parts of the heating element except the upper part, such a phenomenon that said parts of the filter 16 are cooled by air coming in from a very small slit between the ventilating fan mainbody 12 and the front shutter 17 at the exhaust time of decomposed waste gas down to a temperature lower than that in the other parts is prevented to occur. |
