| 摘要 |
PURPOSE:To raise a molding speed and facilitate settig of temperature and pressure of molten resin, by using a slide block to mechanically move up and down a needle valve. CONSTITUTION:In an injection molding machine of hot runner type having the needle value 9 adapted to be moved up and down mechanically through the motion of a slide block 12, a rightward movement of the slide block 12 by a hydraulic cylinder and the like causes rise of a pulling-up pin 15 along a alant face 14 of the slide block 12 and simultaneously rise of the needle valve 9. The needle value 9 is in an integral relationship with the pin 15 and therefore a gate hole 7 opens and a hot runner 5 is communicated with a cavity 8. Becuase that the gate hole 7 can be opened without any relatonship with the resin pressure, the pressure and temperature of resin can be set freely, and high quality products can be obtained. Also, the molten resin can be prepressed and accordingly molding speed can be raised. |
