Sensors And Actuators - Brother MFC7050C Service Manual

2.3

Sensors and Actuators

This equipment has the following sensors:
Sensor name
Hook switch sensor
Cover sensor
Registration sensor
Document front sensor
Document rear sensor
Ink empty sensor
Carrier home position sensor
• Hook switch sensor which detects whether the handset is placed on the handset mount.
• Cover sensor which detects whether the top cover is closed.
• Registration sensor which detects the leading and trailing edges of paper, which allows the
controller to determine the registration timing and check paper jam.
• Document front sensor which detects the presence of documents.
• Document rear sensor which detects the leading and trailing edges of pages to tell the control
circuitry when the leading edge of a new page has reached the starting position and when the
scan for that page is over.
• Ink empty sensor which detects the density of a printed ink-empty mark.
• Carrier home position sensor which detects whether the carrier is in the home position.
Each of the above photosensors consists of a light-emitting diode and a light-sensitive transistor.
The ink empty sensor is a reflection type. Other photosensors are a photointerrupter having an
actuator separately arranged as shown on the next page.
Type Located on
Mechanical switch Hook switch PCB in the handset mount
Mechanical switch Cover sensor PCB
Photosensor Main PCB
Photosensor Document sensor PCB of the control panel
PCB ASSY
Photosensor Document sensor PCB of the control panel
PCB ASSY
Photosensor Ink empty sensor PCB
Photosensor Sensor FPC
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