| 摘要 |
PURPOSE:To prevent plasticated synthetic resin from becoming solidified in lamination and to prevent the same from becoming separated in lamination by a method wherein filling of the plasticated synthetic resin is made under relatively high pressure and after the filling, flow of the resin inside a cylinder of a molding machine main body and in a cavity of a mold is stopped instantaneously, or as quickly as possible. CONSTITUTION:The pressure of an electromagnetic relief valve 23 is controlled so that it can be set high in order to inject plasticated synthetic resin for filling a cavity 18 under high pressure and at high speed, preferably in a short time of 0.1-0.8 seconds, and thereby pressure oil is supplied from a pressure oil source 25 to an oil-hydraulic piston 27. A screw 19 is moved forward by operation of the pressure oil. The pressure oil is preferably pressurized at 1000-1500kg/cm<2>. The set pressure of the electromagnetic relief valve 23 is decreased in proportion to resin pressure that declines exponentially as cooling of the plasticated synthetic resin progresses, and thereby dwelling pressure is decreased with the pressure applied to the piston 19 decreased. |
