| 摘要 |
PURPOSE:To obtain a shut-off nozzle for plastic injection molding which is small in size, easy to operate, durable and capable of manufacturing a product of good quality, by streamlining the passage of resin and providing a large vessel for a spring-containing section by dividing a torpede section into the front section and the rear section. CONSTITUTION:A nozzle is composed of a nozzle head 1 which is connected to a mold of product, steamlined torpedoes 2a and 2b constituting a part of a passage 8 of resin and an adaptor connected to a resin-supplying unit, and the torpedoes 2a and 2b in the front and rear sections are positioned by a knock pin 6. When a pin 4 moved backwards by overcoming the force of a spring 5 by the ratio between resin pressure and sectional area of the shut-off pin 4, a gate 9 is opened. When the resin pressure dropped at the end of the injection, the force of the spring 5 overcomes the resin pressure to push the pin 4 forwards and close the gate 9 to keep the resin from dripping. |
