| 摘要 |
PURPOSE:To relieve stress and improve crack-resistnce, by placing a separatable separator at a portion where no air duct exists in circular direction in the air duct, and by winding a fiber-reinforced layer around their circular surface. CONSTITUTION:Grooves 7, 7' of certain depths are formed close to air ducts 6 on upper and lower ends of a molded coil 11 at a portion 6' where no air duct exists in circular direction in the air ducts 6. A separatable separator 9 is placed at a secondary coil of the grooves 7, 7' to overlap both ends in circular direction to the air duct 4 and to overlap upper and lower ends in axial direction to the bottom of grooves 7, 7' through a molded resin layer 8' equivalent to the thickness of air duct. A fiber-reinforced layer 10 is wound around the circular surface of the separator 9 and air ducts 6. This prevents coils 1, 2 from sticking through the resin layer 8' and relieves the stress. |
