| 摘要 |
PURPOSE:To enable a screw rotor to be formed through injection molding together with intended improvement in its durability by constructing the surface layer of a rotor consisting of a synthetic resin layer with fluororesion, and the second or subsequent layers with Polyphenylene-sulfide resin. CONSTITUTION:A male screw rotor 1 comprises a metallic shaft 2 and a rotor 3 for cover this shaft, and the rotor 3 is so constructed as laminating a core layer 4, a intermediate layer 5 and the surface lay 6 made of respective kinds of synthetic resin are laminated in the radial direction in this order. The surface layer 6 is made of fluororesin and the intermediate layer or subsequent layers are made of polyphenylene-sulfide-resin. Thus, many characteristics required for a screw used under extremely severe conditions are well satisfied and a screw rotor with a low price, a light weight and high accuracy in its size can be obtained. |
