XJ128 and XJ128 Plus Printhead
XJ128 Guide to Operation
Xaar Document no: D031010302 Version A
Page 44
8.2.2 Short-term maintenance
Short-term maintenance is performed between printing runs, for example at the start of the run and/
or at the end of the run. It is recommended to be an automatic function of the system to ensure
repeatable and reliable execution.
8.2.3 Long-term maintenance
Long-term maintenance is performed at the end of the day or when the system is powered down,
and is not in use. This may include capping or flushing the printheads clean of ink with a suitable
flushing solution.
8.3 Printhead maintenance methods
A maintenance routine may use one or more of the following methods. Please refer to the Ink and
Printhead User Guide documentation for recommendations on which methods suit particular
printhead and ink combinations.
8.3.1 Pressure purge
The pressure purge maintenance technique has two main functions:
Flush the nozzles clean of air or contamination
Flush the nozzle plate clean of contamination
7
The method consists of increasing the ink supply pressure until ink is forced through the printhead
and out of the nozzles. Figure 8.1 below shows the typical pressure supply needed to perform a
pressure purge.
Figure 8.1 - Pressure purge details
If the printhead has an operational temperature different to that of ambient then a
pressure purge could introduce a temperature drop and affect performance, therefore a
“
re
-warming
”
period may be required before operation can resume.
7
Ink and system dependant
2-4 sec.
1 to 1.5 kPa
7
-0.1kPa to
–
0.5 kPa
7
0 kPa
Ink Supply
Pressure
Time
