Chapter 22-90Lift cam sensorThis is a photo-interrupter-type sensor. The lift motor is driven by a predetermined number of pulses received after blocking of the sensor light by the flag, thuscontrolling the heights of the head and platen.Environmental temperature sensorThe environmental temperature sensor installed on the carriage PCB detects the temperature around the carriage.The resistance of the thermistor that changes with the temperature inside the printer is reported to the main controller via the carriage PCB.The environmental temperature is used to calibrate the head sensor and to detect abnormal head temperatures.Head temperature sensorThe diode-type head temperature sensors installed at the top and bottom of the printhead nozzle unit are used to detect the head temperature.The diode voltage that changes with the nozzle unit temperature is reported to the main controller via the carriage PCB.The detected head temperature is used to control the head operation and to detect abnormal head temperatures.Printhead contact detectionThe printhead contact status is detected by testing the electrical conductivity.It is detected according to the voltage changes at the two terminals of the contact faces, power supply terminals, and GND terminal.
