Brother DCP-6690CW, Service Manual, Page: 82 / 506

3-28 Confidential
[ 3 ] Mechanisms constituting the head maintenance mechanism
(1) Head capping mechanism
The ASF motor drives the head capping mechanism. When the power is off or the machine is
not printing, this mechanism fits the head cap unit (which contains two head caps) tightly over
the print head to prevent the head nozzles from drying up and to keep dust off the head nozzle
surface.
The head cap unit is mounted on the head cap holder and supported by the spring.
When the head/carriage unit returns to its home position, it presses the mode switching lever
(shown on
pages 3-34 and 3-35 ) to the right so that the clutch gear L engages with the cap lift
cam gear (purge mode). Driving the ASF motor rotates the cap lift cam so that the cap lift arm
raises the head cap holder, fitting it tightly over the head nozzle surface.
(2) Carriage lock mechanism
This mechanism locks the head/carriage unit to prevent the head nozzles from getting out of the
head cap unit accidentally due to external vibration or impact when the machine is not printing,
when the power is off, or during transport.
A part of the head cap holder acts as a carriage lock. When the head cap holder rises in head
capping operation, the carriage lock also comes up to lock the head/carriage unit.
Purge gear
Cap lift cam
Cap lift arm
Head cap holder
(3_12)
Head cap unit
Carriage lock
(Part of head cap holder)
ASF changeover gear
Cap lift cam gear
Air cap stopper
(For duplex print models only)