Epson TM-U950 Technical Manual page 51

CONFIDENTIAL
Carriage sensor assembly
The carriage sensor assembly detects carriage motor rotation problems by using a rotary
encoder. It consists of a set of gears mounted on the carriage motor wheel and a carriage sensor.
This sensor uses an LED and photo IC arrangement. On the outer circumference of the carriage
sensor gear, six sensor plates are mounted with equal spacing. This gear is driven by the carriage
motor via carriage motor gear and ribbon feed transmission gear. The sensor plates pass
between the LED and photo IC, blocking the light and causing a change in the output level of the
photo IC. This change is used to generate the carriage motor rotation signal.
Figure 2-7. Carriage Sensor Assembly
Auto-cutter sensor assembly
The auto-cutter sensor assembly uses the brush contact principle and consists of the cutter slider
assembly and a contact pin holder sub-assembly. This sub-assembly carries three contact pins:
for ground, reset signal, and full cut/partial cut (F/P) position signal. The contact pins contact
the print pattern on a sensor board mounted on the cutter slider assembly. When the drive gear
moves the cutter slider assembly, the reset and F/P signals are generated.
Figure 2-9. Contact Pin Holder Sub-assembly
2-6 Mechanism Configuration and Operating Principles
Figure 2-8. Carriage Sensor Circuit Diagram
Figure 2-10. Relation of Contact Pin
and Contact Board
Rev. A