Carriage Drive Mechanism - Brother MFC5490CN Service Manual

3.2.2.3 Carriage drive mechanism

The head/carriage unit, which integrates the print head unit and carriage, is supported and
guided by the CR guide rail and CR support chassis. The CR timing belt transmits the carriage
motor rotation to the head/carriage unit. Clockwise motor rotations move the head/carriage unit
to the right; counterclockwise ones to the left.
The CR encoder sensor on the top of the head/carriage unit scans the CR encoder strip above
the CR support chassis to monitor the current head position relative to the home position. The
controller uses this signal for robust control ensuring uniform speed.
The CR encoder strip is a clear film striped in a 1/150 inch cycle. It offers a choice of three
travel speeds of the head/carriage unit, 57.7, 43.3 and 21.7 ips, to match the print resolution.
CR encoder sensor
Head/carriage unit
CR guide rail
(Paper feed roller)
CR support chassis
Idle pulley
3-37
CR encoder strip
Carriage motor
pulley
Carriage motor
CR timing belt
(3_21_BHL9)
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