| 摘要 |
PURPOSE:To improve the injection performance and the injection brake performance and to make possible the injection molding positively, by providing a throttling section in a resin path at the forward section of an injection cylinder, and making the resin path between the throttling section and a nozzle hole diametrically larger than the nozzle hole diameter. CONSTITUTION:An injection screw 6 is inserted in an injection cylinder 1 movabley and rotatably an injection and rotation driving apparatus and is composed of a screw 7 and a screw head 8. A throttling piece 10 is mounted in a cylinder head 3 or a nozzle 4 so that a throttling section 12 is formed in a resin path 11 at the forward section of the injection cylinder 1 and the throttling section 12 and a resin path 13A and a resin path 13B located respectively before and after the throttling section 12 are continued by tapered sections 14A, 14B. The diameter of the resin path 13A on the side of the nozzle hole 15 is made larger than the nozzle hole 15. The throttling piece 10 includes the throttling section 12 and the tapered sections 14A, 14B, is cylindrical, and may be made of a steel, but prefereably is made of a material low in thermal diffusivity in the case where the heat-up of shearing of resin is to be used, such as zirconia, etc. |
