Service manual

EPSON LX-300+ Revision A
Operating Principles Printer Mechanism (M-3M10) 47
CARRIAGE HOME POSITION (HP) DETECTOR
The table below is the HP detector specifications.
HP detector detects the signal right after when the CR motor switches the
phase.
2.2.2.1 High speed skip method
At no-printing area, the carriage moves at high speed compared to the
normal carriage speed at printing. This is called carriage control.
2.2.3 Ribbon Mechanism
2.2.3.1 Ink Ribbon Shifting Mechanism
Ink ribbon shifting mechanism: CR motor drives timing belt and the timing
belt driven pulley drives the ribbon shifting gears.
2.2.3.2 Color Ribbon Driving Mechanism (Option)
Color ribbon driving mechanism: shifts the color ribbon up and down to
change the color area of the ribbon to be printed.
Color ribbon mechanism consists of the color shift (CS) motor, CS cam,
ribbon detector, CS lever assembly and color cartridge holder. Color ribbon is
installed on the color cartridge holder.
When CS motor revolves, 1) the pinion revolves CS cam, 2) the CS lever
assembly on the CS cam shifts the color cartridge holder up and down and 3)
drives ribbon up and down.
Table 2-5. HP detector Specifications
Item Specification
Method Mechanical contact method
Switching rate 0.6 to 1.0 mA, 5 VD±5%
Switching mode
• out of HP: close
• within HP: open
Table 2-6. CS Motor Specifications
Item Specification
Motor type 2-phase/48-pole PM stepping motor
Coil resistance 150
Ω
±5% (25°C, per 1 phase)
Control method uni-polar rated voltage drive
Phase drive 2-2 phase
Drive voltage 36.75 ± 1.75 VDC
Consuming current
• Operating, peak current: 245 mA
• Non-operating: 20 mA
Drive frequency 500 pps