PRINTING DEVICE

PURPOSE:To always obtain a stable back tension by providing a sheet holding means adapted to be engaged with a sheet spool core, a means for increasing the rotational speed thereof, a brake drum secured at a position coaxial with the output shaft thereof, a brake arm and a means for pressing the arm onto the brake drum. CONSTITUTION:When an ink film 11 is pulled out from a supply section thereof, the rotation of the supply section is transmitted to through a core gear 12 to a speed increasing gear 16 which therefore comparatively increases the rotational speed during the rotation is transmitted to a brake gear 18. However, if the wind-up diameter of the ink film 11 is large, the rotational speed of the brake gear 18 is not so high. When the wind-up diameter becomes small, the rotational speed of the brake gear 18 is comparative high. In such a case, a centrifugal force acts upon a weight 23 on a brake arm 20 so that the brake arm 20 moves away outward. Accordingly, the pressing force by a brake member 22 decreases. Thus, it is possible to maintain the back tension of the ink film 11 at a substantially constant value.