Tooling: External Double-Ejection Systems
Adaptable to a variety of mold sizes, the double-ejection systems control the sequence of double ejections or plate openings, with users able to set travel distance.
The new double-ejection systems, launched at K 2019 by CUMSA, control the sequence of double ejections or plate openings. There are three types—EX, EY, EZ—and each version controls travel, which is determined by the customer, so that they stop at the selected plates in a locked position while the other plates continue to move.
CUMSA says all three styles feature external set up and simple maintenance; easy installation; robust design; and four different rod diameters: 14, 20, 32 and 50 mm. The EX External Superior Plate Separator is available in four sizes and can be used in two different situations—a pre-opening plate movement of the mold and a double-ejection system. In this setup, the EX controls two sets of ejector plates so that when the machine actuates, the upper ejector plates are set. The first opening width is customizable up to 250 mm for the two smaller EX sizes. For the two larger versions, width ranges up to 375 mm.
The EY External Double Ejection line, which is also available in four sizes, was designed for molds where the upper set of ejector plates are separated, and the machine actuates the lower set of ejector plates. The upper set stops at the core plate, while the rear plate continues to travel until it reaches the upper plate. This series can customize the first opening from 30 to 80 mm.
The EZ External Plate Synchronized model is available in four different sizes as well, and was designed to allow synchronized mold plates openings, regardless of their location. With this design, once the first stroke is defined, the selected plates will open at the same time, and then the rest of the mold will open freely. The first stroke is customizable up to 250 mm for the two smaller sizes, and up to 375 mm in larger sizes.
CUMSA also notes that extension rods are available for the EX, EY and EZ lines, enabling the use of the external double-ejection systems in taller molds.
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