Integral drawing type box girder internal mold and using method thereof

The invention relates to an integral drawing type box girder inner mold and a using method thereof.The integral drawing type box girder inner mold comprises two folding side molds, the two folding side molds are spliced with each other, and a connecting piece is arranged at the splicing position of the two folding side molds; the folding side mold comprises two mold plate units which are hinged to each other, a connecting rod mechanism is arranged between the two mold plate units which are hinged to each other, and the connecting rod mechanism comprises two connecting rods which are hinged to each other and two connecting bases which are hinged to the ends of the two connecting rods respectively. The two connecting bases are rotationally connected to the inner sides of the two formwork units correspondingly, and the rotation axes of the connecting bases are parallel to the rotation axes of the formwork units. And driving rods for driving the ends, away from the hinge seats, of the connecting rods to move in t