FX-1180/FX-880 Service Manual
Chapter 2 Operating Principles
Rev. B
2-2
2.2 PRINTER MECHANISM
This printer mechanism consists of Printhead, Paper feed mechanism, Carriage movement
mechanism, Tractor feed mechanism, Platen gap adjustment mechanism, Ribbon feed
mechanism, PF motor, CR motor, detectors, and so on.
2.2.1 Printhead
The printhead prints data from the control board on paper using the ink ribbon. The printhead is
mounted on the carriage unit.
2.2.2 Paper Feed Mechanism
The paper feed mechanism picks up paper and transports it to the printhead, then ejects the paper
step by step or continuously driven by the PF motor. PF motor drives the paper feed mechanism
gears and the platen roller. The top of form and paper out condition are detected by the front and
rear PE detector, respectively.
2.2.3 Carriage Movement Mechanism
The carriage movement mechanism carries the carriage unit left and right along the CR guide
shaft and mechanism frame, and stops it at any position for printing. It is driven by torque sent
from the CR motor via the timing belt. Home position is detected by the HP (home position)
detector at power on and CR motor phase changing timing.
2.2.4 Tractor Feed Mechanism
The tractor feed mechanism feeds continuous paper to the printhead and ejects it. Torque from
the PF motor is transferred to the tractor unit via the release mechanism in the paper feed
mechanism. The release lever in the release mechanism switches torque from the PF motor
between cut sheet feeding and continuous paper feeding. This printer is equipped with several
tractor feeding methods (front / rear push tractor feeding, front / rear push & pull tractor feeding
and front / rear pull tractor feeding), which is selected according to the tractor unit setting positions
and the lever positions. The tractor detector detects the release lever setting position, for cut sheet
feeding or continuous paper feeding.
2.2.5 Platen Gap Adjustment Mechanism
The platen gap (the gap between the platen and the printhead) adjustment mechanism consists of
CR guide shaft, parallelism adjustment bushing, PG adjust lever and PG detector. PG adjust lever
is attached to the left side of the CR guide shaft. The bushings are attached to the both sides of
the frame. As the both sides of CR guide shaft are eccentric toward external form of them,
printhead approaches or recedes from the platen roller as the PG lever turns forward or backward.
PG detector detects PG lever position. If the lever is set to a position between “2” and “6”, the
printer is in the copy mode.
2.2.6 Ribbon Feed Mechanism
The CR motor drives the ribbon feed mechanism via the timing belt. The ribbon feed mechanism
has the sun and planetary gear system. No matter the carriage unit is driven left and right, the ink
ribbon is driven in one direction.
Summary of Contents for FX 890 - B/W Dot-matrix Printer
Page 1: ...6 59 0 18 3LQ PSDFW RW 3ULQWHU EPSON FX 1180 880 4008484 ...
Page 9: ...PRODUCT SPECIFICATION 3 7 5 ...
Page 23: ...OPERATING PRICIPLES 3 7 5 ...
Page 30: ...TROUBLESHOOTING 3 7 5 ...
Page 49: ...DISASSEMBLY AND ASSEMBLY C H A P T E R ...
Page 72: ...ADJUSTMENT 3 7 5 ...
Page 80: ...MAINTENANCE 3 7 5 ...
Page 85: ...APPENDIX 3 7 5 ...
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