| 摘要 |
An arrangement for monitoring the approximate temperature of a resistive heating element selectively energized at a plurality of power levels in response to the selection by an operator of one of a plurality of power settings including OFF, which includes a heater energy counter to provide approximate heating element temperature information. The heater energy counter is incremented at a rate which is approximately proportional to the rate of increase of the temperature of the heating element when energized at the selected power level. In one form of the invention, the counter is decremented when a lower power setting or an OFF setting is selected, at a rate which is approximately proportional to the rate at which the temperature of the heating element decreases in cooling down to the temperature level associated with the new power setting. By this arrangement, the count of the counter approximately tracks the heating element temperature, thereby providing approximate temperature information. This temperature information can be used to energize an indicator light when the count of the counter exceeds a predetermined threshold count corresponding to a temperature above which the element is uncomfortably hot to the touch, which light remains energized regardless of whether the element is ON or OFF until the count is decremented below the reference value, thereby providing a visual signal to the operator that the heating element is hot. |
