| 摘要 |
PURPOSE:To mold a reinforcing material containing rubber pipe, a metal pipe or a pipe using a thermoplastic material as a bent pipe having all of curvatures by extrusion by appropriately changing the interval of an annular gap from an equal width due to two concentric circles to a non-uniform width due to two circles different in center. CONSTITUTION:An extruded bent pipe forming part 11 is constituted of a core 12, the feed-out guide body 13 fitted onto the core 12 so as to provide an annular gap 11a almost the same as the wall thickness of an incomplete pipe 1, the extrusion die 14 fitted onto the leading end part of the core 12 so as to provide a predetermined annular gap 4 to form an extrusion port 3 and appropriately movable in the direction of the surface crossing the center axial line of the core 12 at a right angle and the extrusion cylinder 16 pushing the incomplete pipe 1 on the opposite side of the extrusion port. Since extrusion resistance is low on the widening side of the gap 4, a material is fastly extruded and, contrarily, on the narrowing side of the gap 4, the material is slowly extruded. As a result, the incomplete pipe 1 is molded in a bent state. |
