Based on a machinery platform Athena developed five years ago, the Niigon machines feature a combination of servo ball screws and servo-pump technology, said Luke Osmokrovic, engineering customer support manager for Athena. The machines, which do not have servo valves, feature an on-demand servo pump that precisely manages hydraulic functions. Servo ball screws are used for clamping movements.
Designed for stack and cube molding, a bottom-mounted propeller drive mechanism, or center section, supports a cube mold or two conventional molds mounted back to back. The center section has dedicated linear support rails and uses the same high-load linear bearings as the moving platen.
Athena said a Niigon 150 unit with 165 tons of clamping force supports cube or back-to-back molds weighing up to 5,511 pounds. Even the heftiest tool causes the support beam to sag only 0.003 inch. Meanwhile, Niigon 300 models can handle weights of up 13,227 pounds, Osmokrovic said.
Because of their two-platen design, Niigon stack/cube machines can accommodate a full-size injection unit on the moving platen end of the machine in-line with the mold center line, Osmokrovic said.
Ten percent of the maximum clamping force is available to pull the molds apart. The propeller mechanism handles this mold break force, which is consistent and repeatable.
When configured with two injection units, conventional hot-runner systems can be used. Niigon machines can be equipped with fully integrated, third-party, hot-runner controllers. They sit about 6 inches off the floor, providing space for operations such as conveying, as well as maintenance and cleaning. They come equipped with a 28.5-inch multitouch HMI.
Niigon machines have mold water and hydraulic oil routed to the center of the rotary table. The mold is accessible from both sides, as well as the top. All machine utilities connect to one end of the machines.
Earlier this year, Athena shipped a Niigon 150 machine configured with two in-line reciprocating screw injection units, each with a 50mm screw. Two robots for part handling were fully integrated into the machine with direct control from the HMI, allowing post-mold operations on both sides of the cube within a machine width of only 7 feet.