Patent ID: 7942595

Claim:
A gear unit apparatus for a printer, comprising: a printer bracket; a printing section that has a platen roller rotatably attached to the printer bracket and performs printing on a printing paper; a transfer roller that is rotatably attached to the printer bracket and transfers the printing paper; a drive motor that rotary drives the platen roller and the transfer roller; a belt group that transmits rotary driving force of the drive motor to the platen roller and the transfer roller; and a gear group that is engaged with the belt group, wherein a unit bracket that is detachable to the printer bracket is provided independently of the printer bracket, the drive motor, the belt group and the gear group are assembled to the unit bracket, and, when the unit bracket is attached to the printer bracket, a platen roller gear of the platen roller and a transfer roller gear of the transfer roller are engageable with the gear group; and wherein the unit bracket is provided with a unit bracket side engaging/disengaging section that is engageable/disengageable with a printer bracket side engaging/disengaging section formed in the printer bracket, a part of the gear group of the unit bracket is engageable/disengageable with the platen roller gear and the transfer roller gear on the printer bracket side by means of engagement/disengagement between the printer bracket side engaging/disengaging section and the unit bracket side engaging/disengaging section, and leading end sections of the printer bracket side engaging/disengaging section and the unit bracket side engaging/disengaging section that face each other are formed into a taper shape, the unit bracket side engaging/disengaging section comprising a plurality of gear shafts of the gear group, the printer bracket side engaging/disengaging section comprising a plurality of engaging/disengaging holes with which the plurality of gear shafts can be engaged/disengaged, the plurality of gear shafts being engaged/disengaged with the platen roller gear and the transfer roller gear by engaging/disengaging the plurality of engaging/disengaging holes.