Carriage Mechanism - Epson SEIJ98006 Service Manual

EPSON Stylus Color 900

2.2.1 Carriage Mechanism

As shown in Figure 2-1, the carriage unit with the printhead on it moves
right and left, depending on the rotational direction of the CR (Carriage)
motor. Table 2-1 shows the CR motor specifications.
Table 2-1. CR Motor Specifications
No. Item
1 Motor Type 4-phase / 200-pole / HB-type stepping motor
2 Drive voltage 42 VDC
3 Coil resistance 5.8
4 Drive mode Bipolar constant current drive
The CR unit position is always memorized and controlled by the CRHP
(Carriage Home Position) sensor. This sensor confirms the CR position
to renew the memory at the following timing:


When power is turned on / off


When a head cleaning operation, including initial ink charge, is
performed.


When the printer returns to a ready status because the printer
has executed print job or receives no data for one second or
more.
See Table 2-2 and Table 2-3 which show the CRHP sensor
specifications and CRHP sensor switch mode, respectively.
Operating Principles
Specifications
5% (Applied to the driver)
10%
Printer Mechanism Operating Principles
Table 2-2. CRHP Sensor Specifications
No. Item
1 Type
2 Drive voltage
3 Collector resistance
Table 2-3. CRHP Sensor Switch Mode
CR Position Switch mode
Within the CRHP
Open
range
Off the CRHP range Close
If this sensor is defective or does not work, it does not detect the
carriage while the carriage is in the home position seek mode. In this
case, the printer cuts off electricity to the CR motor and shows a fatal
error.
Like the Stylus Pro5000, the Stylus color 900 also uses a linear encoder
to obtain secure carriage movement and accurate print timing. The
linear encoder reads slits on the encoder belt (linear scale) above the
timing belt to control the carriage. See Table 2-4 for the linear encoder
specifications.
Revision C
Specifications
Photoelectrical transfer system
(SHARP GP1S73P2)
5 V 5%
30 VDC or less
Sensor output
0.7 VDC or less
2.4 VDC or more
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