A pneumatic
radial tire and a method for manufacturing the same, a device for forming a band of
radial tire, and a method of and device for forming a belt-band-
tread rubber
assembly. The pneumatic tire including a belt arranged on the radially outer side or a carcass, and a band arranged on the radially outer side of the belt and composed of continuous one to several organic
fiber cords wound spirally and approximately parallel to the circumferential direction of the tire. The
radial tire manufacturing method including the steps of laminating the predetermined number of belt plies on a belt drum or belt ring for forming a belt, and winding one to several organic
fiber cords continuously and spirally in the cicumferential direction of the belt on the outer surface of the formed belt in order to form a band. The band forming device including a means for drawing out a cord to be wound, a means for traversing the letting-off means in the widthwise direction of the belt, and a means for controlling the
traverse of the letting-off means. The method of forming belt-band-
tread rubber assemblies comprising a step of expanding the
diameter of belt drum so that the shape in axial section of belt drum becomes the same or approximately the same as the finished shape of the band in
vulcanization mold. The
assembly forming device including a
diameter-variable belt drum comprising a stretchable forming annular body made of an
elastomer, and a means for expanding and contracting the
diameter of the annular body, wherein the shape in axial section of the circumferential surface of the annular body in the diameter.