| 摘要 |
PURPOSE:To enable to control easily a thickness of parison, by a method wherein a throttle valve reducing an area of a flow path is provided in the middle of a nozzle flow path and an opening part of the same is made to incline to the central axis by a predetermined angle. CONSTITUTION:Although a disturbance is generated in a flow of molten resin through a difference in length in a deformed part P of a nozzle flow path 7, the disturbance is mitigated through an inflow into an expansion chamber Q and the disturbance is mitigated further through a matter that the flow is narrow by a narrowing part R. Although the other end M of the nozzle flow path 7 possesses inclination angles theta0, theta1 in a long-diameter side and short-diameter side respectively, when a flow path thickness (t) of a lead-out part S is made to vary by moving a mandrel in a vertical direction, if theta0=theta1 is given, a uniform thickness can be obtained extending over the whole circumference of parison. With this construction, a disturbance of a resin flow can be prevented easily at low cost without performing deformation of an adjusting part of an inside die and a good resin blow-molded article can be molded. |
