By replacing a standard induction or frequency drive motor with a permanent-magnet servo motor, the Maxima Servo injection molding machine from Milacron Plastics Technologies is said to offer energy efficiency, reliability and part quality "rivaling" an all-electric, according to the manufacturer, but at a lower price point.
The 2-platen clamp design also allows the machine to apply pressure directly to the center of the mold instead of at the corners, differing from some competitive servodriven hydraulics and promoting better platen parallelism, which can lead to more consistent parts.
Brian Bish, hydraulic platform product manager for Milacron noted in a release that the new Maxima Servo line manages to combine the energy savings of most all-electric presses, with the small footprint and center tonnage cylinder of a 2-platen. According to Milacron, the energy savings can offer a return on the initial cost premium in as little as 6 months.
Instead of using an induction motor running at a fixed speed, the Maxima's servomotors can vary in speed from 0 to 3000 RPMs in both directions, responding to work load with very high resolution, since rotation can be controlled by a fraction of an angle. In additon, an internal gear pump replaces an electro-hydraulic pump, with the benefits of only running when needed and requiring less maintenance.
By centrally locating tonnage cylinder behind the moving platen, the Maxima provides clamping force directly behind the mold, reducing platen deflection and concentrating uniform force across the mold surface. This not only reduces mold wear, but allows superior force distribution across the mold's parting lines for cleaner parts.
The Milacron Maxima Servo is available globally from 310 to 4400 tons. The company also offers hybrid versions of these machines.