| 摘要 |
PURPOSE:To prevent the generation of a weld line by providing a prescribing member to the peripheral edge part surrounding the diffusion space at the central part of a cavity and introducing a synthetic resin being a raw material into the diffusion space to appropriately prescribe the flow of the synthetic resin diffusing and flowing from the central part to the peripheral edge part. CONSTITUTION:A synthetic resin molding machine 1 is constituted of a pair of upper and lower molds 2 and a raw material injection apparatus 3 injecting a raw material in the molds 2 from the upper surfaces thereof. Three prescribing members 8, 9, 9 are arranged at three places of the position opposed to the gate 7 communicating with a cavity 5 and positions respectively having an angle of 120 deg. left and right from said position so that the leading ends of three prescribing members are abutted from three places. These members are retracted in the diameter direction of the cavity 5 to prescribe the flow of the injected synthetic resin raw material. The flow of the injected molten resin is prevented from such a phenomenon that the leading end part thereof is divided to flow and the divided flows meet in the cavity 5 and the cavity 5 can be filled with the resin by the unified flow of the whole. |
