Overview - Epson Stylus PHOTO 1270 Service Manual

EPSON Stylus Photo 870/1270

2.1 Overview

This section describes the operating principles of the printer mechanism
and electrical circuit boards. The major components of the EPSON Stylus
Photo 870/1270 are:
"
Printer mechanism: Stylus Photo 870: M4T10
Stylus Photo 1270: M4S60
"
Main board: C304MAIN Board
"
Power supply board: C298PSB/PSE Board
PRINTER MECHANISM
Unlike other EPSON ink jet printers, the EPSON Stylus Photo 870/1270 uses
a DC motor as power source. The DC motor enables the printer to lower
noise during printing. Table 2-1 shows various motor types used in the
printer and their applications.
Table 2-1. Motor Types and Corresponding Applications
Motor Name Type
DC motor with
CR motor
brush
DC motor with
PF motor
brush
4-Phase / 48-
Pump/ASF
pole stepping
motor
motor
OPERATING PRINCIPLES
Application / Feature
Drives the carriage making little noise.
Works with a linear scale to monitor motor's
operating condition.
Supplies power to drive paper feeding
rollers used to send paper at specified
speeds and load/eject paper. To monitor
paper feeding pitch, a loop scale is attached
beside the high-precision gear.
Sends drive for pump operation and paper
feeding from ASF. Since this is a stepping
motor, it has no scales or photo sensors that
are used to monitor motor's operating
condition.
The basic structure of the printer mechanism is mostly common to the
Stylus COLOR 400, except that the Stylus Photo 870/1270 uses a Pump/
ASF motor. With this motor equipped, the paper loading mechanism and
the pumping mechanisms are independently driven, which allows the
printer to offer higher throughput.
Figure 2-1 shows the printer mechanism block diagram for the Stylus
Photo 870/1270.
Intermittent Gear
PF Motor Pinion
PF Motor
Flashing Window
(at 80th or 136th column)
Photo Interrupter (Encoder)
Notched Roller
Carriage Unit
Printhead
Timing Belt
Cap Unit
(without a valve)
Pump Unit
CR Guide Shaft
PF Roller
Liner Scale
Figure 2-1. Printer Mechanism Block Diagram
Overview
Revision B
Rotary Encoder
PF Drive Gear (high precision)
Photo Interrupter (Encoder)
Detector Wheel
ASF Sensor
LD Roller Shaft
Loading Rollers
PE Sensor
Pump/ASF Motor
ASF/Pump
CR Motor Disengage Gear Train
PG Lever
33