| 摘要 |
PURPOSE:An ultra-high-speed injection unit which is designted to accumulate a prescribed volume of plastic materials, ejected from an in-line screw type injecting device, in a forward gap section of an ejection plunger in an injection cylinder and move the plunger forward into a metallic mold cavity. CONSTITUTION:Shut-off valves 15 and 19 are closed and resin material which is put in from a hopper 6 of an in-line screw device 1 is moved forward in a heating cylinder 2 by a screw 5 to be plasticized, and keeping the material accumulated in a forward gap section 2a of a screw head 5a, the screw 5a is moved back to a prescribed position. And then, an opening section 17a of the valve 15 is set to a passage 7, and by operating a hydraulic cylinder 4, the screw 5 is moved forward to shift the material in the gap section 2a to a gap section 14 and keep a plunger 10 moving backward until a hydraulic ram 11 hits a stopper 18 located on a prescribed position. During this period of time, pressure of the material in the gap section 14 is increased to a prescribed value by operating the screw 5, and the passage 7 is closed by the valve 15. Injecting operation is conducted by working directly onto the hydraulic cylinder 12 and also by connecting a nozzle 22 with a flow passage 23 by a valve 19. |
