Ribbon Switch Mechanism Unit; Switching From Black To Red; Releasing From Red To Black - Casio UP-250 Technical Manual

movable blade drive pin in direction E to make the blade execute a cut. If the motor continues
rotating, the wormwheel makes one rotation and it makes the movable blade return to the
standby position and the cutting is finished.
Wormwheel
Movable blade

Ribbon Switch Mechanism Unit

The ribbon switch mechanism unit consists of the carriage motor assembly, carriage sub assembly,
tension plate assembly, tension belt pulley, home position detector assembly, ribbon frame assembly,
ribbon frame spring, ribbon switch lever, ribbon release lever, and ribbon release spring.
The mechanism unit is placed at the left and right of the carriage sub assembly, whose position is
controlled by the number of carriage motor steps, using the home position as the reference position.
It switches between the black and red ribbon in the ribbon switch and ribbon release areas outside the
printing area.

Switching from Black to Red

When the carriage, sub assembly (print head unit) moves in direction E and reaches the ribbon switch
area, the ribbon switch lever is pushed by the ribbon switch section and moved to position A (shown by
the dotted lines). The ribbon assembly frame is pushed upward by the push face for the ribbon frame.
The detent face for the ribbon switch falls into the ribbon switch lever hole in the ribbon frame assembly
and the ribbon frame assembly is set to the red position.

Releasing from Red to Black

When the carriage sub assembly moves in the D direction and reaches the ribbon release area, the
ribbon release lever is pushed by the ribbon release section. Then portion C pushes theribbon frame
assembly upward. At this time, the detent face for the ribbon switch is released from the ribbon switch
lever hole in the ribbon frame assembly and the ribbon switch lever is returned to ribbon switch lever
position B (shown by the solid lines) by the spring power of the
Movable blade drive pin
Wheel pin
Figure 2-14 Auto-cutter mechanism
Slot D
Arm
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