| 摘要 |
PURPOSE:To provide a synthetic resin molding which allows to inject or extrude at lower molding pressure by a method wherein resin to fill a mold is injected or extruded under the state being applied by pressure shock waves with the specified repeating frequency. CONSTITUTION:Molding material is fed from a feeder 13 in a cylinder 6 by controlling the driving motor of the compactor 14 and an encoder 16 in a screw type extruding device 2 through a controlling device 5. In addition, a screw 7 is pivoted by controlling a motor and an encoder 18 also through the controlling device 5. Further, the molding material is heated and melted by controlling a heating coil 10 through an inverter 19, which is also controlled by the controlling device 5. The molten molding material passed through the injection hole of a nozzle 11 provided at the tip of a cylinder 7, is metered at the cylinder tube 20 of an injection cylinder device 3 so as to be poured in a mold by the predetermined amount. During the period of pouring the material, pressure shock waves with the repeating frequency of 100-500Hz are applied with a shock wave application device 57 to the molding material lying in a flow passage ranging from a nozzle 30 to a cavity. As a result, thixotropic phenomenon develops and the fluidity of the molding material increases and accordingly the desired molding is done at comparatively lower molding pressure. |
