| 摘要 |
PURPOSE:To detect the end of a recording paper simply and assuredly by detecting difference between the condition of the recording paper remaining on a winding core of a recording paper roll and the condition of no recording paper remaining thereon. CONSTITUTION:The difference between the condition of recording paper 2 remaining on a winding core 9 of a recording paper roll 1 and the condition of no recording paper 2 remaining thereon is detected to detect the end of rolled recording paper 2. In this case, by utilizing a difference between the color (usually white) of the recording paper 2 and the color (black and so on) of the winding core 9 specific to its quality, and a reflection-type photo sensor 10 disposed adjacent to the peripheral surface of the recording paper roll 1, detected is the difference between the quantity of light reflected from the recording paper 2 when the recording paper 2 remains on the winding core 9 and the quantity of light reflected from the winding core 9 when no recording paper 2 remains on the winding core 9. Thus, the existence of the recording paper 2 on the winding core 9 can be judged simply and assuredly. |
