DUSSELDORF, GERMANY - At K'95, suppliers of controls for injection molding machines focused on mastery of the molding cycle's transition point, and continued to roll out software that is easier to use. Control software introduced at K'95 in Dusseldorf by automatically fine-tunes an injection molding machine's closed-loop control.
Barber-Colman hopes to make the Impact Advanced Process Control available Jan. 1, said John Searle, head of international marketing and sales. Impact will be available on all Maco Custom 400, Maco 4000 and Maco 4500 controllers. The firm claims the software enables a molder with little knowledge of process control theory to set up a machine.
Barber-Colman has installed one unit at an automotive molder in the Detroit area, he said. Four injection press makers are evaluating Impact for possible use. Three patents are pending.
Impact creates a theoretical model of complete molding cycle, then compares it against actual molding on each shot. The software also includes a proprietary algorithm that automat-ically monitors and optimizes control at the transition point, when the machine switches from injection to the pack/hold stage. That eliminates pressure spikes found with other control systems during transition, Barber-Colman claims.
The Loves Park, Ill., firm also said it has boosted the number of possible temperature control points on the Maco 4000, 5000 and 6000 series of controllers by adding a high-density temperature card that increases the number of temperature loops from six to 12 per card.
Maco 4000 controllers also now include a die height adjustment feature for toggle clamp injection presses.
An Automatic Quality Control System introduced at K'95 detects in every injection shot when the mold cavity is full, ensuring an optimum transition point from the fill stage to the pack stage, said its Swiss supplier, Kistler Instrumente AG Winterhur. Kistler Instrument Corp. of Amherst, N.Y., is the U.S. unit.
The system monitors internal pressure of the mold, tracking fluctuations. Information is displayed on a monitor screen reflecting trends so an operator can see from a distance whether production is stable or drifting.
Kistler also showed a new nozzle pressure sensor and a new, less expensive melt pressure and temperature sensor for extrusion, called Dual Monitor Type 4801.
Sharing Kistler's booth was Moldflow Pty Ltd. of Australia. The firm is moving its computer software from the design shop to the injection molding floor, with the introduction of Intelligent Process Control technology. IPC automatically sets up, monitors and controls how the plastic performs inside presses.
Instead of tracking the ram, the system predicts the flow of polymers at any given point, instead of focusing on the machine. The plastic is controlled to match an ideal ``fingerprint.''
Moldflow said that, since plastics are compressible, the ram has to move a further distance before there is a significant flow of plastic. That means that, during mold fill, the volume being displaced by the ram is significantly different from the volume that is injected into the cavity.
Moldflow's strategy during K was to market IPC to press makers for new machines, said John Rowland, general manager of process control. IPC also is available as a retrofit item on existing machines. Moldflow's U.S. unit is Moldflow Inc. of Shelton, Conn.
