| 摘要 |
PURPOSE:To perform exchanging of resin in a short time without consuming the excessive resin and prevent productivity from lowering, by a method wherein a resin exchanging accumulator having a piston arranged in a direction crossing with a resin passage in the middle of the resin passage between an extruding machine and die housing is provided. CONSTITUTION:In a die inner accumulator type blow molding machine, this is constituted so that molten resin is supplied through a resin supply port of a die housing 1a, molten resin is allowed to dwell within a resin passage space formed of a plunger 22 which is fitted concentrically over a core metal 7 and capable of an up-and-down movement of a metal 7 of the central part of the die housing 1a by passing through a resin passage engraved in the outer circumferential surface of a sleeve 31 within the die housing 1a and a parison 20 is obtained by discharging the dwelt molten resin into a tubular state through an outlet slit 8a of a die 50. Then in the middle of the resin passage between an extruding machine 23 and the die housing 1a, a resin exchanging accumulator 40 having pistons 41, 42 which are arranged in the crossing direction by communicating with the resin passage. |
