Carriage (Cr) Mechanism - Epson Stylus COLOR 1520 Service Manual

2.2.3 Carriage (CR) Mechanism

The CR mechanism is composed of the CR unit, timing belt, CR guide shaft, paper eject frame, HP
sensor (Home Position sensor) and CR motor. The CR motor sends torque to the timing belt to move the
CR unit in the both right and left directions along the paper eject frame and CR guide shaft. A stepping
motor used for the CR motor enables the CR unit to move and stop at any position. The CR is primarily
detected at the home position by HP sensor when the printer is turned on and its position is then
controlled by the open loop. Table 2-2 and Table 2-3 show the specification for the CR motor and the CR
motor drive terms, respectively.
Item
Motor type
Drive voltage
Coil resistance
Excitation mode
Drive frequency
Minimum step
Print Print speed
mode
Draft 400 cps
LQ 200 cps
SLQ 100 cps
Rev. A
Table 2-2 CR Motor Specification
4-phases / 200-pole / HB type stepping motor
42 VDC 5% (The voltage applied to the driver)
5 7% (at 25 C per 1 phase)
Unipolar drive
1-2 phase, 2w1-2 phase : Constant current drive
480 ~ 9600 Hz
0.106 mm (1-2 phase drive)
0.026 mm (2W1-2 phase drive)
Table 2-3 CR Motor Drive Terms
Acceleration Acceleration
1 2
0.96 0.96
0.96 0.96
0.90 0.90
Figure 2-4. CR Mechanism
Description
Constant Deceleration
0.70 0.70
0.70 0.80
0.60 0.80
Operating Principles
Deceleration
1 2
0.70
0.80
0.80
2-5