Method for automatically setting injection molding speed condition in injection molding machine

摘要

A reference pressure of melted material injected to a mold cavity of a mold is set as a function of injection passing time from a start of an injecting process or a function of a distance of movement of an injection plunger, and the movement of the plunger is started at a temporarily constant injection speed. A correction value of the injection speed is obtained to eliminate a difference between a sensed pressure of the melted material injected to the mold cavity of the mold and the reference pressure in a range that the sensed pressure of the melted material exceeds the reference pressure during the injection passing time from the start of the injection process wherein the plunger is started to move or during the movement of the plunger, and the injection speed is corrected in accordance with the corrected value. The corrected value of the injection speed, and the injection passing time from the start of the injection process or the distance of the movement of the plunger, those of which corresponding to the range, are memorized in a memory unit, and are characterized to a desired injection speed pattern, and the pattern is read out from the memory unit as an injection molding speed condition.