Injection Molding: Two-Platen Vertical Press Has Lower Mold Table
Mold table at waist height instead of shoulder height is more ergonomically efficient.
The Japanese parent of Nissei America has introduced a new servohydraulic vertical-clamp press that boasts 10% lower overall height and 30% lower mold-mounting height than conventional machines. This is said to make mold installation, setup, insert loading and product takeout easier than ever before. The new TWX220RIII25V (220 tons) is developed from the Nissei TNX-RIII Series, but its mold table is at waist height (1 meter) instead of shoulder height as on the preceding series.
The more ergonomic height is due to the new two-platen hydromechanical clamp, similar to those on horizontal presses. It incorporates a high-speed traverse cylinder and high-pressure clamping cylinders and half-nut mechanisms on the tiebars instead of the conventional hydraulic clamp that controls both high-speed and high-pressure clamp movements with one cylinder. This clamp reduces oil requirements by more than half. Furthermore, the three-tiebar press has 100-mm greater stroke and maximum daylight than before, accommodating larger and more complex molds. Standard configuration has two lower mold halves and one upper half. Nissei says the turntable can be converted easily to three-stage operation with an additional stage for operations before or after molding.
The optimized bed structure is said to permit flexible robot mounting. Turntable motion and ejectors are driven by servomotor for increased speed, smooth motion, and highly precise positioning, which can prevent misalignment of inserts, according to Nissei.
The TACT IV controller has a 15-in. color touchscreen that can accommodate two vertical windows open side by side. It is said to permit improved quality and production management by making operation history and data search easy. Maintenance functions are also said to be enhanced. Control cycle speed is 500 microsec.
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