| 摘要 |
An apparatus for controlling the heating element(s) which is/are used for demisting a surface of an object is provided with temperature detectors which are used separately to detect the surface temperature of the object to be demisted and the temperature and humidity of the ambient air, a comparison circuit comparing the temperature of the surface of the object with a surface control temperature which is calculated from the temperature and the humidity of the ambient air. When the surface temperature is found to be lower than the surface control temperature, the comparison circuit feeds a signal to a semiconductor relay, which causes the latter to activate the demisting heating element to heat the surface of the object, thus preventing vapours in the ambient air from condensing into moisture on the surface of the object. If the surface temperature is found to be higher than the surface control temperature, a signal is emitted to terminate the heating of the surface of the object. |
