Brother MFC5490CN Service Manual page 37

This chapter gives an overview of the scanning and printing mechanisms as well as the sensors,
actuators, and control electronics. It aids in understanding the basic principles of operation as well as
locating defects for troubleshooting.
3.1 OVERVIEW ............................................................................................................ 3-1
3.2 MECHANICAL COMPONENTS ............................................................................. 3-2
3.2.1 Scanner Mechanism.................................................................................. 3-5
3.2.2 Printing Mechanism................................................................................... 3-8
3.2.2.1 Ink supply and ink jet mechanism ......................................................... 3-10
[ 1 ]
[ 2 ]
[ 3 ]
[ 4 ]
[ 5 ]
[ 6 ]
3.2.2.2 Head maintenance mechanism............................................................. 3-24
[ 1 ]
[ 2 ]
[ 3 ]
[ 4 ]
[ 5 ]
[ 6 ]
3.2.2.3 Carriage drive mechanism .................................................................... 3-37
3.2.2.4 Paper pulling-in, registration, feeding and ejecting mechanisms .......... 3-41
3.2.3 Sensors and Actuators .............................................................................. 3-47
3.3 CONTROL ELECTRONICS ................................................................................... 3-50
3.3.1 Components .............................................................................................. 3-50
CHAPTER 3 THEORY OF OPERATION
CONTENTS
Overview ........................................................................................... 3-10
Features ............................................................................................ 3-11
Head/carriage unit............................................................................. 3-12
Ink cartridges..................................................................................... 3-19
Ink refill assembly.............................................................................. 3-22
Ink supply tubes ................................................................................ 3-23
Overview ........................................................................................... 3-24
Maintenance unit components .......................................................... 3-25
Mechanisms constituting the head maintenance mechanism........... 3-27
Power transmission route to the head maintenance mechanism
and motor rotational direction............................................................ 3-32
Purge types, ink usage, purge counts, and purge codes .................. 3-35
Ink cartridge capacities and the number of printable pages
per ink cartridge ................................................................................ 3-36
Confidential