Brother International IntelliFax-3550 Service Manual - Page 24

Paper pulling-in and registration mechanism Solenoid lever Clutch release lever Solenoid spring Clutch spring Paper feed solenoid Gear drive unit Heater roller drive gear Paper ejection roller drive gear Pull-in roller drive gear Intermediate gear Clutch gear Planetary gear system (Front) Main motor Gear 20/90 Drum drive gear The paper pulling-in and registration mechanism consists of the pull-in roller gear (incorporated in the multi-purpose sheet feeder), planetary gear system, paper feed solenoid, solenoid lever, clutch release lever, and registration sensor. (For the details about the sensor, refer to Section 2.3.) If the main motor rotates clockwise, the rotation is transmitted to the intermediate gear of the planetary gear system. As the intermediate gear rotates, the pull-in roller drive gear also rotates since the clutch gear is locked by the solenoid lever and the clutch release lever. Accordingly, the pull-in roller in the multi-purpose sheet feeder rotates to pull in paper into the equipment, a sheet at a time. If the paper feed solenoid is retracted and the clutch release lever is operated according to the cam profile of the pull-in roller gear so as to release the clutch gear, the clutch gear rotates and the pull-in roller drive gear does not rotate. In this way, the clutch gear switches the transmission of the motor rotation on and off to the pull-in roller drive gear. The solenoid on/off timing and the clutch release lever timing allow this mechanism to pull in a sheet and register it against the registration roller. Paper feeding and ejecting mechanism If the main motor rotates clockwise, the rotation is transmitted via the gear train to the drum drive gear, heater roller drive gear, and paper ejection roller drive gear. After the paper passes through the heat-fixing process, it will be ejected onto the paper tray. If the leading edge of the paper pushes up the actuator of the paper ejection sensor, the photo sensor becomes opened, signaling the start of paper ejection. If the trailing edge has passed through the sensor actuator, the sensor becomes closed, signaling the completion of paper ejection. Then, the main motor stops rotation. III - 5