3 ] Head/Carriage Unit - Brother DCP6690CW Service Manual

[ 3 ] Head/carriage unit

The head/carriage unit consists of a front end (ink-jet head) and a back end (damper and air vent
unit) as shown below.
The front end consists of metal plates laminated together and etched to form ink flow channels.
Piezoelectric ceramic actuators generate the spray pressure. The response of individual front
ends to applied voltages and waveforms varies, however, because of the nature of piezoelectric
materials, fluctuation in manufacturing accuracy, and other factors. The front end therefore
leaves the production line with head property labels giving property data. The manufacturer
writes this property data to the EEPROM on the main PCB incorporating this unit. Based on the
property data of the front end, the processor drives piezoelectric ceramic actuators to insure
consistent performance without fluctuations.
(Front)
Head driver
Filter
Piezo plate
Metal plates
Nozzle plate
3-13
Back end
(Buffer and air vent unit)
Front end
(Ink-jet head)
(Head)
Confidential