Epson STYLUS Scan 2500 Service Manual page 44

EPSON Stylus Scan 2500
CARRIAGE LOCK MECHANISM
The carriage lock mechanism prevents the carriage from being left at an
uncapped position for a long time which can occur due to user mistakes,
physical shock, vibration during transport, and so on. The CR lock mechanism
is driven by the stepping PF motor. See Table, " PF Motor Specifications," on
page 40 for motor specifications.
The PF motor controls the CR lock mechanism as well as the PF mechanism
depending on the direction of the PF motor rotation. The CR lock mechanism
is located at the right end of the paper eject roller.
Top view
Pump Planetary
Bushing 6
Paper Eject
roller
Planetary
Middle frame Lever Guide
Figure 2-11. CR Lock Mechanism
While the PF motor drive is used for paper feeding (PF motor rotation = CCW),
the CR Lock Lever is set under the Paper Eject Frame. But the CR Lock lever
rises up and locks the carriage when the PF motor rotates CW.
Operating Principles
Right-side view
Lever
Carriage
CR Lock
Lever
Pump
Printer Mechanism Operation
The PF motor drive is sent to the CR Lock lever via the Paper Eject roller.
PF Motor pinion gear (CW rotation)
Gear 28 Paper Eject Roller
If the carriage is left uncapped for a long time, ink on the printhead surface
gradually thickens and may clog the nozzles. In some cases, the nozzles may
be so thoroughly clogged that they cannot be cleared even after performing
multiple cleaning operations.
To prevent clogged nozzles, the printer caps and locks the carriage in the
following conditions.
V Power off sequence:
When power is turned off, even during printing, the printer caps and
locks the carriage at the end of the power-off sequence.
V Power on sequence:
When power is turned on, the printer automatically performs an
automatic (power-on) cleaning cycle and then caps and locks the
carriage.
NOTE: The power-on cleaning cycle is an automatic head cleaning
sequence that is performed every time the power is turned on.
The timer IC, which is powered by the lithium battery,
measures the length of time the printer has been off. The
printer selects and performs the appropriate cleaning
operation according to the length of time it has been off.
V Paper eject sequence:
When the Load/Eject button is pressed, the printer ejects any paper in
the paper path. If no print data is received at this time, the printer caps
and locks the carriage and then enters the standby mode.
However, if no paper is in the paper path when the Load/Eject is
pressed, the printer loads a sheet and does not lock the carriage.
PF motor torque is always transmitted to the CR lock lever side, but the
operation of the CR lock mechanism varies depending on the rotation
direction of the motor.
Clockwise = sets the carriage lock lever
Counterclockwise= releases the carriage lock lever
Revision A
Gear 73.6 Combination gear
CR Lock Lever
44