Epson TM-H6000 Service Manual page 99

Confidential
Home position detection mechanism
The home position detection mechanism is located at the left end of the head carriage assembly.
This mechanism keeps track of the head carriage assembly movement position. The initial
settings are made by detecting the detection plate at the rear of the head carriage assembly.
The home position detector consists of an LED and photo IC. When the head carriage assembly
is moved, the detection plate passes between the LED and photo IC. The photo IC output level
changes when the light rays are interrupted. This change in output level is used as a detection
signal for the head carriage movement position.
Carriage detection mechanism
The carriage detection mechanism uses a rotary encoder interlocked to the carriage motor gear
to detect abnormal carriage motor rotation.
This mechanism is comprised of the carriage drive transmission gear and carriage detector,
which are located on the carriage motor shaft.
The carriage detector consists of an LED and photo transistor.
The driving force generated by the carriage motor is transmitted to the carriage motor gear,
carriage drive pulley, carriage belt, carriage transmission pulley, and the carriage drive
transmission gear, which is located at an equal interval on the inside of the gear, where the
screening plate is located. When the carriage drive transmission gear is rotated by the driving
force of the carriage motor, the screening plate passes between the LED and photo transistor.
The output level of the photo transistor changes at this time, since the light rays are interrupted.
This output level is used as the detection signal for carriage motor rotation.
Appendix D-8 Product Overview
Printer side
+5V
GND
head carriage detector assembly
Figure D-10
Printer side
+5V
GND
Screening plate
Figure D-11
When light is emitted
High
When light is
interrupted
Low
GND
Signal level at point A
When light is emitted
High
When light is
interrupted
Low
GND
Signal level at point A
Rev. A