Patent ID: 8708445

Claim:
A printing device comprising: a driving motor that applies a driving power rotating a roll body in which a medium is rolled; a holder that holds the roll body and that transfers the driving power of the driving motor to the roll body; a transport motor that applies a driving power transporting the medium rolled out from the roll body; a transport roller that is provided further to the downstream side than the roll body in a transport direction of the medium and transfers the driving power of the transport motor to the medium; a looseness amount acquiring unit that acquires an amount of looseness between the holder and the transport roller; and a controller that controls the driving motor when the amount of looseness is equal to or more than a predetermined amount of looseness, the controller controlling the driving motor on the basis of the amount of looseness acquired by the looseness amount acquiring unit, and when the amount of looseness is less than the predetermined amount of looseness, the controller controlling the driving motor on the basis of tension between the holder and the transport roller, wherein the looseness amount acquiring unit includes a sensor which detects a position of the medium in a vertical direction, and wherein the sensor is arranged extending from above the medium to below the medium when the medium is tight.