| 摘要 |
PURPOSE:To carry out gas injection molding without the trouble of solidified resin generated at a nozzle end section by moving forward and backward a plunger and opening and closing alternately a nozzle for resin provided at the front end of a nozzle cylinder and a fluid injection path by means of a gate device. CONSTITUTION:When given injection pressure is applied to molten and plasticized resin by a screw 2 for the purpose of injecting the resin into a mold, a plunger 9 is moved forward together with a finger pin 12 resisting to a compression spring 13 and slide cores 11, upper and lower, are moved respectively upward and downward to communicate an outlet 93 with a nozzle 6 for resin, and an opening for fluid injection path 7 and a flow inlet path 7a are closed by the end and the side surface of the upper finger pin 12. Then, the given volume of resin is injected into the mold to release resin pressure by the screw 2 close the nozzle 6 for resin and open the fluid injection path 7. Pressurized fluid from a pressurized fluid source is passed through a pipe 14, the flow inlet path 7a, a recessed section 86 and the fluid injection path 7 by said arrangement, and injected from an injection port of the mold into the resin in the cavity to mold a hollow molded product. |
