Print Head Unit Movement; Wire Movement When A Single Dot Is Printed - Casio UP-250 Technical Manual

Print head unit movement

When the carriage motor is driven and the carriage motor gear moves in the direction of arrow B
(forward rotation), the rotational power is conveyed to the belt drive pulley, then the belt. Next,
the carriage sub assembly, which is fixed to the belt, moves in the direction of arrow B.
When the carriage motor gear rotates in the direction of arrow A (reverse rotation), the carriage
sub assembly moves in the direction of arrow A.

Wire movement when a single dot is printed

When the specified print head drive pulse is input to the drive coil, the iron core is magnetized,
and the actuating plate is pulled in the direction of arrow A. This action pushes the wire toward
the platen. When the wire strikes the ink ribbon and paper against the platen, a single dot is
printed. (The "platen" is the portion of the paper feed frame being struck by the wires during
printing.)
When energizing of the drive coil is completed, the wire and actuating plate are returned to the
standby position by the wire return spring and actuating plate spring.
Belt
Carriage sub assembly
Figure 2-3 Print head unit movement
Wire return
spring
Actuating
plate
A
Figure 2-4 Printing
Carriage motor gear
Belt drive pulley
Paper roll
Ink ribbon
B
Wire
Wire guide
Iron core
Drive coil
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Platen