Epson Stylus Color, Service Manual

Page: 46 / 151

Chapter2 Operating Principles
Rev. A
2-9
The figure below shows carriage mechanism. The print head as a core of the printing mechanism is
installed in the carriage unit. This print head keeps the angle of print head in flexible and adjustable
structure by moving the adjustment lever up and down with the Angular adjustment mechanism.
(Refer to chapter 4 for more details) Also, parallelism adjustment lever is mounted on right side of the
carriage guide shaft and it adjusts parallelism between paper and shaft when this shaft is installed to the
printer mechanism.
After this adjustment is completed, operating the PG adjustment lever makes possible to change the
space between the surface of paper and print head surface into 2 phases; either 1.04mm to 1.94mm. It is
possible to vary the space between the surface of paper feed assembly and the print head by rotating the
axis of carriage guide shaft which itself is decentralized, with the operation of PG lever. This is the
mechanism that user can adjust the appropriate PG value by himself according to the paper thickness or
any other environmental conditions such as paper curl.
Carriage lock mechanism is to prevent the carriage from being left uncapped for a long time because of
vibration during the printer transport or mishandling by the users. If the carriage is left uncapped for a long
time, an ink on the print head surface gradually becomes viscosity. As a result, the nozzle will be unable to
discharge ink. To make matters worse, the nozzle may be completely clogged by the viscosity ink and it
may not be able to return to the normal condition just by the normal cleaning operation. In order to prevent
this, printer goes to carriage lock state at the following conditions.
After Power OFF operation:
If the power is turned off during the printing or any other performance, carriage lock will be
performed in the end after completing initialize operation.
After power ON operation:
After power is turned on and automatic P-On Cleaning(power on cleaning) is performed, then
carriage lock will be performed. The timer IC always counts printer’s power OFF time by using
the power of lithium battery mounted on the C209 main board. P-on cleaning function
automatically selects the cleaning level according to the time which the printer is not in used.
After Eject the paper:
After Load/Eject button is pressed and the paper is ejected, if the data is not input, the printer
performs carriage lock and goes to standby state. However, if the paper is loaded to the printer
inside by Load/Eject button, the printer does not perform the carriage lock operation.
Carriage home position Sensor
Carriage Motor
Timing Belt
PF Roller
Paper Feed Motor
Eject Roller
Paper guide(Front)
Carriage Unit
Front Side
Rear Side
Parallelism
Adjust Lever
Carriage
Guide Shaft
Fixing Bush
Figure 2-8. Carriage Mechanism(Top Viewing)