INJECTION MOLDING MACHINE

• Main Author: YAMADA AKIO
• Format: Patent
• Language: English
• Published: 08.12.2011
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PROBLEM TO BE SOLVED: To provide an injection molding machine that has a high responsiveness of drive control of an electric servomotor for injection molding in an injection and pressure keeping steps, and molds with a high efficiency a high quality thin product, a highly precise product, or a thick product.SOLUTION: The injection molding machine makes a determination (secondary pressure position determination), when it reaches a VP (velocity/pressure) switching position, whether a secondary pressure position sis set behind the VP switching position (secondary pressure position s≥the VP switching position), or ahead of the VP switching position (secondary pressure position s<the VP switching position). In the case of the secondary pressure position s≥the VP switching position, the machine retreats a screw 1 to the secondary pressure position sat a high speed, and switches to a control corresponding to a pressure keeping pattern pat the stage of an injection pressure reaching a predetermined secondary pressure. In the case of the secondary pressure position s<the VP switching position, the machine advances the screw 1 to the secondary pressure position sat a high speed, and switches to a control corresponding to the pressure keeping pattern pat the stage of an injection pressure reaching the predetermined secondary pressure. This control is repeated until the final pressure keeping setting pressure during the pressure keeping step.