Patent ID: 7971953
Filing Date: 2011-07-05
Classification: B41J,B65H

Abstract:
1. A recording-medium-residual-quantity detecting device comprising: a first rotation-quantity detecting unit that detects a rotation quantity of a roll in which a recording medium is wound; a first driving unit that applies a rotational power to the roll; a second rotation-quantity detecting unit that detects a rotation quantity of a transportation roller that transports the recording medium by rotating in contact with the recording medium that is unwound from the roll; a second driving unit that applies a rotational power to the transportation roller; and a controlling unit that controls the first driving unit and the second driving unit, wherein the controlling unit has a winding control mode in which the first driving unit and the second driving unit are controlled so that rotational powers to wind the recording medium into the roll without slack between the roll and the transportation roller are applied to the roll and the transportation roller, and wherein a residual quantity of the recording medium is calculated on the basis of a rotation quantity θr of the roll and a rotation quantity θs of the transportation roller that are respectively detected by the first rotation-quantity detecting unit and the second rotation-quantity detecting unit when the winding control mode is executed.