Patent ID: 7249726

Claim:
Apparatus for winding filamentary material in a figure 8 configuration, comprising: a rotatable spindle for retaining a mandrel upon which the filamentary material is wound; a traverse mechanism for controlling the laying of wound coils on the mandrel; means for controlling the wound layers on the mandrel in accordance with the rotation of the spindle and the movement of the traverse mechanism to vary the angular displacement, radial displacement between successive coils, of the wound coil so that the number of cross-overs of succeeding layers of the wound coils increases as the winding process progresses, the advance of the wound coil, thereby increasing the density of the wound coils; wherein the advance, φ 1 , is determined from the following equations to determine the angular displacement of the coil: φ=COS −1 ( Rm /( Rm+D )); (1) and where: Rm=Radius of the mandrel; D=Diameter of the filamentary material; and φ/cos[24]=φ 1 (2).