Coordinated debut for Cartesian beam robots

The first of series of new Cartesian beam robots offering longer strokes, bigger payloads and a rigid structure designed for speed has been debuted by Sepro America LLC (Pittsburgh, PA). The Model S5-35 is a mid-size robot designed for injection molding machines with 350 to 700 tons of clamping force. Other sizes, for smaller and larger molding machines, are scheduled to debut later this year and in 2011.

Compared to a robot of comparable size in the existing Generation 4 (G4) range, the S5-35 offers a standard payload of 15 kg, a 25% increase. The 900-mm strip stroke is 12.5% longer than the maximum available on the current G4 unit, meaning the S5-35 can handle parts with deeper draw.  At the same time, however, the wrist and arm are actually 10% smaller so the mold does not need to open as far and cycle times can be reduced.

This increased level of performance is achieved without limiting speed, which is pegged at 3.5 m/sec on the horizontal stroke. Other important specifications include a 2000 to 7000 horizontal stroke and a 1400-mm vertical stroke that can be extended with an optional telescopic arm to 1800 mm.

Key features include a compact, space-saving control cabinet mounted on the beam, precision CNC rotations allowing precise positioning and superior flexibility required for complex applications (insert placing, stacking, etc.), and a 'Y-free' function, which provides for the programmed release of the strip-axis motor, allowing free movement of the robot arm and load-free ejector tracking. An optional elastic wrist allows for minor positioning inaccuracies while softening contact between the gripper and mold.-Stephen Moore