To accurately calculate a remaining amount of roll paper only based on a detection result.
This paper remaining amount calculation device 1 holds axial both ends of the roll paper formed by winding long paper around a paper tube by a spool shaft and a stopper, rotatably supports the roll paper by a bearing via the spool shaft, detects at least an outer diameter position of the paper tube and a side end face of the paper wound around the paper tube by a paper remaining amount detection sensor in a sensor 2 arranged in the stopper in the radial direction of the roll paper, and outputs a detection signal to a CPU 8 via a support side communication part 3. Based on the detection signal, the CPU 8 determines an outer diameter of the paper tube, an outer diameter of the paper from the outer diameter position of the paper tube to an outer diameter position of the paper wound around the piper tube and paper thickness of one piece of the paper so as to calculate the remaining amount of the paper wound around the paper tube.
SATO NOBUYUKI
KOBAYASHI MASATO
HORIKAWA DAISAKU
