Annular three-dimensional structure

Claim 1

Annular three-dimensional structure constituted by the regular criss-crossing of filiform elements distributed in a plurality of families of elements, each family being composed of elements of a same type occupying the same particular position within the structure, said structure comprising first and second families of meridian rectilinear elements, oblique with respect to the axis of the structure and forming, in each family, meridian sheets regularly distributed about the axis of the structure, and third and fourth families of helical elements forming, in each family, cylindrical sheets of the same axis as the structure and distributed regularly in radial direction, the inclination with respect to the axis of the elements of the first family being equal but opposite to that of the elements of the second family and the helical paths of the elements of the third family having the same pitch as those of the elements of the fourth family, but with an opposite orientation, structure wherein a fifth family is further provided which is selected from the group constituted by a family of radial elements forming meridian sheets distributed regularly about the axis of the structure, a family of circumferential elements forming cylindrical sheets having the same axis as the structure and distributed regularly in radial direction and a family of axial elements forming meridian or cylindrical sheets distributed regularly in the structure.