| 摘要 |
PROBLEM TO BE SOLVED: To easily form a new rubber sectional region on the opposite side of an extruder while enlargement of the extruder is not generated and the change of a preformer-set is restricted as small as possible by a method wherein the rubber discharging from one extruder is allowed to flow by branching into this side and the back face side of the extruder. SOLUTION: In a first preformer 7, a plurality of kinds of rubber are discharged through a plurality of feed openings 11 arranged in the longitudinal direction of the preformer 7 to an inflowing port 4. On an inflowing surface Si, a first and a second branched imflowing parts 14A and 14B, which dividedly accept a rubber sent through one feed opening 11, are provided. At the same time, on an outflowing surface So, an outflowing port 5 including a first and a second branched outflowing parts 15A and 15B, to which the rubbers sent from the first and the second branched inflowing parts 14A and 14B are separated, is formed. A second preformer 9 koins the rubbers sent from the separated first and second branched outflowing parts 15A and 15B and finally sends out through a sending-out port 23. |
