To make a winding device adapted to a curved outer shape of a vehicle body since the whole of a winding device is small, and to prevent the winding device from malfunctioning and being failed.

Metal wires forming a helical spring are assembled to both ends of a sheet, and winding is performed by an effect of the helical spring at winding. Further, by using a helical spring of a head-cut conical shape as the helical spring, a superposed part of sheet both ends is prevented from being largely swelled to hardly generate rupture for the winding. Further, a non-linear shaft is adopted as the winding shaft, the winding device is adjusted to the curved outer shape of the vehicle body and is not projected from the outer shape of the vehicle body. Further, a crank type winding mechanism with easy handling is assembled to a winding shaft end.