The movement performance of clamping unit in the internal circulation two-platen injection molding machine

Injection molding machine (IMM) is an advanced manufacturing equipment, which integrates mechanical, electronic, hydraulic and automatic control technology. IMM is the most important production tool and more than 80% of plastic products is manufactured by injection molding. Clamping unit is an important component of IMM. Thanks to the use of internal circulation cylinders, no additional oil is needed during the mold-moving stage and thus ensures the high mold-moving speed. The connection of the four mold-locking cylinders ensures even pressure in the cylinders. This results in completely uniform force distribution. The platen can be self-adjusted according to the parting surface of the mold. Equipping with gear-type mold height adjusting mechanism shortens the mold-locking cylinder stroke and the time of pressure rising. This paper describes the classification of two-platen clamping unit and details how the internal circulation clamping unit works. The movement performance is analyzed combined with experimental tests and theoretical calculations finally.