PURPOSE: To correct any warp of a chart without increasing the number of part items even in the case where the chart warps after completion of the recording, and also to enable the quality improvement of a recorded chart.

CONSTITUTION: As a paper delivery roller mechanism of a printer, two roller members 19 and 20 different in outer diameter are installed. As for these two roller members, one side is a first roller member 19 being formed with high- grade material in hardness and composed of a roller member small in an outer diameter, and the other is a second roller member 20 being formed with soft material and composed of a roller member a larger dimensional outer diameter than that of the first one. When they are installed, the first roller member 19 is joined together with the second one 20 in a state that the specified pressure P is imposed on from the upside at all times.