| 摘要 |
PURPOSE:To permit to manufacture the bent tube system resonance type muffler by a method wherein an inner tube, to be penetrated through the muffler, is inserted into a holding fitment at the tip end of a nozzle and a parison is hung, thereafter, the parison, formed in a mold by blowing, is welded by fusion to said inner tube and is solidified. CONSTITUTION:The heated inner tube 1 is inserted into the cylinder 17a of the holding fitment 15 and the parison 13 of a predetermined length is hung at the outside of the cylinder 17a, thereafter, split molds 19a, 19b of the mold 20 are clamped. When pressure air is injected from a flow path 12 into outflow ports 16a, 16b gradually, the parison 13 is formed so as to have configuration of the mold 20 by air flowed out of the small hole 5 of the tube 1, an opening at the lower part of the tube 1 and the hole 16b. In this case, the upper and lower ends of the inner tube 1 are welded to the parison 13 by fusion and are solidified whereby the muffler 10, consisting of a box body 6, a straight tube section 7, the bent tube section 8 an the inner tube 1, may be obtained. Accord ing to this method, the resonance type muffler, having a desired shape may be manufactured simply by blow molding. |
