| 摘要 |
<p>9D RG 12535 A glass-ceramic cooktop surface is provided with a temperature sensor integral with the glass ceramic plate of the cooktop. The temperature sensor utilizes the temperature resistance characteristic of the glass ceramic plate as a means of monitoring the temperature of the plate and is formed in the heated areas of the glass-ceramic plate. The sensor comprises pairs of metallized conductive strips fired to the underside of the plate and terminated in a cool region of the plate. A continuity resistor is provided at the termination point of each pair of strips to distinguish between cold glass conditions and a defective sensor. One strip of each pair is connected to a further metallized strip which surrounds the periphery of the glass and forms a common ground for a heating unit control circuit and is also used as a broken glass detector. Each sensor forms one leg of an AC voltage divider and is connected to an assoicated control c circuit. The output of the voltage divider is applied to two voltage comparators having a common output connected to operate a relay to control heater power to the "burners" of the cooktop which may be open coil heaters or film heaters.</p> |
