摘要 |
PURPOSE:To make it possible to perform a stable molding operation by a method wherein injection speed is gradually lowered by the filling resistance of molten resin during the period ranging from the finish of a filling process to the start of a dwell process. CONSTITUTION:The forward speed of a screw 10 is controlled by speed changeover positions and speeds which are set on the speed changeover position setters 30a, 30b and 30c and the speed setters 32a, 32b and 32c of a setting device 28. Thus, when the screw 10 advances and reaches a starting position of free reduction of speed set by a starting position setter 34 of reduction of speed a signal which corresponds to a value set at a limiting torque setter 38 is sent from a torque limiter 26 to a controlling device 24 so as to limit a current fed to an injection motor 18. As a result, the speed of a screw 10 is lowered gradually, because the screw 10 undergoes the filling resistance of molten resin. Accordingly, the shifting of the screw 10 due to its large inertial energy and the fluctuation of its shifting time is dissolved and a stable molding operation can be performed. |