Portable miniaturized printer device

A thermal printer, comprising:

• a thermal printing head;
• a recessed accommodation part that accommodates a roll-shaped continuous paper;
• a pair of rack gears arranged in a staircase-like shape on a paper conveyance direction side of the roll-shaped continuous paper accommodated in the accommodation part and having tooth rows arranged in a first direction orthogonal to the paper conveyance direction so as to face each other;
• a pinion gear arranged between the pair of rack gears and configured to fit into the tooth rows of the pair of rack gears;
• and
• a pair of paper guides respectively provided at a position of an upper rack gear of the pair of rack gears closer to a center side in the first direction from one end portion in the first direction and a position of a lower rack gear of the pair of rack gears closer to the center side in the first direction from another end portion in the first direction or the other end portion, and support side surfaces of the roll-shaped continuous paper accommodated in the accommodation part by an opening or closing movement in the first direction by the pair of rack gears and the pinion gear, wherein
• a paper guide of the pair of paper guides, which is provided on the upper rack gear, is mounted to an upper mounting part extending from a back surface of the upper rack gear opposite to the tooth row to the paper conveyance direction side, wherein the upper mounting part is offset away from the pinion gear.

A portable printer, comprising:

• a recessed accommodation part that accommodates a roll-shaped continuous paper;
• a pair of rack gears arranged in a staircase-like shape on a paper conveyance direction side of the roll-shaped continuous paper accommodated in the accommodation part and having tooth rows arranged in a first direction orthogonal to the paper conveyance direction so as to face each other;
• a pinion gear arranged between the pair of rack gears and configured to fit into the tooth rows of the pair of rack gears;
• and
• a pair of paper guides respectively provided at a position of an upper rack gear of the pair of rack gears closer to a center side in the first direction from one end portion in the first direction and a position of a lower rack gear of the pair of rack gears closer to the center side in the first direction from another end portion in the first direction or the other end portion, and support side surfaces of the roll-shaped continuous paper accommodated in the accommodation part by an opening or closing movement in the first direction by the pair of rack gears and the pinion gear, wherein
• a paper guide of the pair of paper guides, which is provided on the upper rack gear, is mounted to an upper mounting part extending from a back surface of the upper rack gear opposite to the tooth row to the paper conveyance direction side, wherein the upper mounting part is offset away from the pinion gear.