Filament Winding Method and Apparatus, and Tank

Abstract

In a filament winding method, while a rotating tank relatively reciprocates in a tank axial direction to a helical winding head, fibers are fed from yarn-feeding sections to the tank. After the tank turns back in the tank axial direction, a large number of fibers are wound around one domed portion and a trunk portion of the tank, and trailing ends of the large number of fibers are located at one end portion of the trunk portion. Then a piece or a small number of fibers are fed from a rotating hoop winding head to the trunk portion, and hoop winding is performed on helical winding layers formed around the trunk portion. Then, at the one end portion of the trunk portion, the large number of fibers pulled from the yarn-feeding sections of the helical winding head are cut off.

1 . A filament winding method for winding fibers around a tank composed of a trunk portion having a uniform radius in a tank axial direction and a pair of domed portions, wherein each of the domed portions communicates with a corresponding end portion of the trunk portion in the tank axial direction and is formed with a diameter that becomes smaller outward in the tank axial direction, comprising the steps of:
 a first step wherein while the tank, which is rotating, relatively reciprocates in the tank axial direction to a helical winding head, fibers are fed from each of a plurality of yarn-feeding sections to the tank, wherein the helical winding head includes the plurality of yarn-feeding sections arranged on a concentric circle around the tank;   a second step wherein after the tank turns back in the tank axial direction, a large number of fibers are wound around one of the domed portions and the trunk portion of the tank, and trailing ends of the large number of fibers are located at one end portion of the trunk portion; and   a third step wherein after the second step, a piece or a small number of fibers are fed from a rotating hoop winding head to the trunk portion, and hoop winding is performed on helical winding layers formed around the trunk portion, and then at the one end portion of the trunk portion, the large number of fibers pulled from the yarn-feeding sections of the helical winding head are cut off.   
     
     
         2 . A filament winding apparatus for winding fibers around a tank composed of a trunk portion having a uniform radius in a tank axial direction and a pair of domed portions, wherein each of the domed portions communicates with a corresponding end portion of the trunk portion of the tank in the tank axial direction and is formed with a diameter that becomes smaller outward in the axial direction, comprising:
 a helical winding head having a plurality of yarn-feeding sections arranged on a concentric circle around the tank, wherein each yarn-feeding section feeds fibers to the tank;   a hoop winding head arranged to feed a piece or a small number of fibers to the tank;   a first moving device arranged to relatively move the tank in the tank axial direction to the helical winding head;   a second moving device arranged to relatively move the hoop winding head in the tank axial direction to the tank;   a controlling device arranged to control movements of the first moving device, the second moving device, the helical winding head and the hoop winding head, wherein:   while the tank, which is rotating, relatively reciprocates in the tank axial direction to the helical winding head, fibers are fed from each yarn-feeding section to the tank,   after the tank turns back in the axial direction, a large number of fibers are wound around one of the domed portions and the trunk portion, and trailing ends of the large number of fibers are located at one end portion of the tank,   then the hoop winding head, which is rotating, feeds a piece or a small number of fibers to the trunk portion and hoop winding is performed on helical winding layers, and   then, at the one end portion of the trunk portion, the large number of fibers pulled from each yarn-feeding section of the helical winding head are cut off.   
     
     
         3 . A tank, whose circumference surface is wound with fibers, composed of a trunk portion having a uniform radius in a tank axial direction and a pair of domed portions, wherein each of the domed portions communicates with a corresponding end portion of the tank in the tank axial direction and is formed with a diameter that becomes smaller outward in the tank axial direction, wherein
 an outermost layer of a large number of fibers wound with helical winding is formed on one of the domed portions and the trunk portion, trailing ends of the large number of fibers are located at one end portion of the trunk portion, hoop winding layers are formed on the outermost helical winding layer formed around the trunk portion, and cut edges of the large number of fibers wound with helical winding are located at the one end portion of the trunk portion.