Abstract: A winding device includes a hand crank, a securing substrate plate, and two unidirectional gears pivotally coupled between the hand crank and the substrate plate by a pivot member. A pivot member is inserted, in one operation, through axial holes of pivot mounting portions of the hand crank and the securing substrate plate, and through a semicircular through holes of the unidirectional gears to pivotally couple the hand crank with the securing substrate plate and unidirectional gears. The pivot member includes two semi-circular pivot portions that are disposed parallel and opposite to each other. Each pivot portion is formed by curling and bending a plate into a semi-circular structure. The pivot portion includes a curved face and two curled portions disposed on an inner side of the curved face. The curled portions have end portions curling in opposite directions and abutting the inner side of the curved face at different points so as to increase the bending strength of the curved face.