US Patent 7416403 Die clamping unit

A die clamping unit includes a stationary platen, a tie bar which is attached to the stationary platen, a movable platen which is movable forwards and backwards along the tie bar with respect to the stationary platen, a first servomotor which moves the movable platen away from the stationary platen in a core-back operation, a second servomotor which moves the movable platen forwards and backwards to perform die-opening and -closing, and a control device which drives the first servomotor to move the movable platen away from the stationary platen and which drives the second servomotor to apply a force to the movable platen in the direction toward the stationary platen in the core-back operation.