Citizen iDP-3210, Service Manual

Page: 6 / 46

iDP-3210 Service Manual
CITIZEN 6/46
2.2 Mechanism and Operational Principle
The basic construction and operational principle of the printer are divided into the following blocks for explanation.
* Power Transmission and Paper Feed Mechanism.
* Sensor Mechanism.
* Print Head Mechanism.
2.2.1 Power Transmission and Paper Feed Mechanism.
The drive force of the motor as power is transmitted from the motor gear fixed to the motor shaft to the platen
roller through the platen gear. The platen gear rotates by this driving force.
The platen roller is pressed to the surface of the heating element of the thermal head by the force
of bar-shaped springs connected to both the ends of the roller. When paper is inserted between the platen roller
and thermal head, it is caught between the roller and the head by the rotation of the roller,
and transferred to the paper outlet being linked with the rotation of the platen roller.
2.2.2 Platen Attaching/Removing Mechanism
The platen roller of the printer, part of the paper feed mechanism, is constructed in a way that allows attaching
and removing. The platen roller block is composed of a platen roller, platen gear, platen bushes, and platen guides.
Setting this block on to the U-supports of the chassis, the platen gear engages with the motor gear.
Further, the platen block has come in contact with the thermal head by means of the platen bushes being pressed
by bar-formed springs one end of which is fixed to the chassis.
The platen roller can be attached/removed by hooking/undoing each movable end of the springs to the hook on
the metal fitting on the chassis.