| 摘要 |
PURPOSE:To reliably pack resin into every part, smoothly perform degassing and prevent the wet face and warp of a disc case from being generated by disposing an injection port at two positions which are covered and hidden by an ordinary shutter and which are located on the carved face of a mold corresponding to the outside of a disc-body containing part, forming a degassing part at a central part on a far side from the injection ports, and setting the thickness of the portion outside the disc-body containing part in a cavity to be thicker than the thickness of the portion of the containing part. CONSTITUTION:An injection port 5 for a molten resin is arranged at two positions symmetrical to a center line l and formed at these positions which are covered and hidden by the shutter 6 of an upper case 1 and which correspond to the outside of a disc-body containing part 1i. The thickness of a portion corresponding to a face plate part outside the containing part 1i is set thicker than the thickness of a portion corresponding to the disc-body containing part 1i in a cavity 4, and a degassing telescopic tube 8 is disposed on a movable mold plate 3 at a central part on a far side from the injection ports 5. The molten resin injected from each injection port 5 into the cavity 4 is packed from one end side to the other end side and also from a thick-wall part to a thin-wall part and eventually reaches the degassing telescopic tube 8, whereby the smooth flow of the resin reliably reaches every part and the degassing can be easily done. |
