1. OUTLINE
EO10-33016A
1.5 Electronics Specifications
1-17
(2) Slit sensor (Transmissive sensor)
The ribbon motor block has three same slit sensors: Two of them are attached to the ribbon
feed motor side, and the other one is to the ribbon take-up side.
A slit sensor is a photo-coupler, consisting of an LED and a transistor.
This sensor detects the amount of taken ribbon, ribbon feed amount, the rotation count of the
ribbon shaft and the ribbon motors, and the direction of rotation.
The slit sensor on the ribbon take-up side detects the amount of taken ribbon by monitoring the
time of detecting slits of the ribbon slit gear.
The two slit sensors on the ribbon feed side detects a ribbon end when the motor rotates in the
reverse direction at a ribbon break or ribbon end.
(3) Top cover open sensor
On each side of the printer, same top cover open sensor is provided. This sensor is a photo-
coupler, consisting of an LED and a transistor. A top cover open status is detected depending
on the two hook plates linked with the top cover release button intercept the photo-coupler or
not.
When a top cover open status is detected, “HEAD OPEN” is displayed on the LCD, the error
LED illuminates, and printing is stopped.
Slit Sensor (Take-up)
Slit
Slit Sensor (Feed)
Ribbon Slit Gear
(Take-up)
Ribbon Slit Gear
(Feed)
Hook Plate
Top Cover Open Sensor