| 摘要 |
PURPOSE:To contrive prevention of a screw damage along with shortening of a building-up period of time of injection molding work by reducing a quantity of remaining resin to be melted as much as possible, by a method wherein the titled prevention device is so constituted that an alarm indication is performed by whether an advancing and of a screw positions at the front part inside a heating cylinder at the time of turning OFF of an electric power source of a heater circuit and at the time of completion of molding the advancing end of the screw is moved up to the front part inside the heating cylinder without fail. CONSTITUTION:When a breaker 9 turning an electric power source of a heater circuit 10 OFF is opened when an advancing end 22 of a screw is not positioned at the front part 23 inside the heating cylinder at the time of completion of molding, as a constantly closing contact point 14 of a relay R1 is closed and a constantly contact point 15 is kept closed also as a limit switch LS1 does not act, too, a buzzer 16 is sounded and a lamp 17 is kept lighting. To make an operator release this alarm, the advancing end 22 of the screw has to move to the front part 23 of the heating cylinder and input to a detection displaying circuit 13 has to be disconnected by an action of the switch LS1. Because of this, it follows that the operator turns OFF the electric power source after the operator has turned ON the electric power source to the heater circuit 10 again to move the advancing end 22 of the screw to the front part 23 of the heating cylinder. |
