| 摘要 |
The invention relates to electric heater units for "smooth top" cookers which employ two or more heater elements in the same unit. It is directed particularly at the problem of monitoring the temperature of the unit and/or the "smooth top" thereover to protect against overheating. It is known to use a thermal cut-out device extending over the heater unit where a single element is used, but design problems develop when two or more elements are employed in the same unit, of which at least one element is independently energizable. According to the invention an elongate thermal cut-out device (10) extends across said one element (10) but is thermally isolated from the other element or elements. Thus, the device operates only in response to the one element. Such thermal isolation can be accomplished by shielding a portion of the device which extends across the other element or elements by means of a block of thermal insulation material, or by means of a tube of thermally conductive material which carries any heat from the other element or elements to a heat sink. |
