The so-called fixing is the process by which the image is fixed in a photocopy medium (such as paper). And fixing component generally includes: the upper fuser roller (roller heating) on upper fuser roller, pressure roller fixing lights under (heat lamps) separation claw (including spring), fixing gears, thermistors, temperature resistance and series of components. In the process of copying, to avoids the color image erased, it must be cured by the fixing device to form the final copy, so the fixing component thermistor is one of the key components of the essential on the copier.
The thermosensitive resistors used by the photocopier fixing component are the thermistor of the negative temperature coefficient, its resistance reduces while the temperature getting increases. We use the property of thermistor to detect the temperature of the hot roll, the temperature of the hot roller is then determined according to the resistance of thermistor. With thermistor built bridge or make resistance converted into corresponding voltage bleeder circuit, through the analog to digital conversion circuit (A/D) make temperature data is converted into digital signals for the CPU, and judging by the CPU temperature whether it is reached constant temperature point, when it comes to the directional drive circuit, the two - way thyristor closes off the signal, stop for fixing the lamp power supply makes the temperature rise, and give the preheating instructions that can be copied. If not, continue to use the thyristor to heat the fixing lamp.
It can be seen that the fixing component thermistor is mainly used for the protection of temperature measurement.