Electric actuators target fluid cylinders

Thursday, November 16, 2000

From low-force to high-force applications and everywhere in between, the latest breed of electro-mechanical actuators is designed specifically for easy replacement of hydraulic and pneumatic cylinders.

E-Drive Design's Eliminator HD(TM) series heavy-duty ballscrew linear actuator offers force with finesse. Designed for engineers converting from hydraulic to electromechanical actuators, the unit achieves greater control of the motion, and eliminates hydraulic related safety and environmental issues, according to Jim Haury, mechanical engineer and E-Drive Design's sales & marketing manager.

Available in four frame sizes with thrust capacities from 2,000 to 24,000 lbf and linear velocities up to 23 inches/sec, the Eliminator HD accepts virtually any motor/gearhead. Haury says that's a benefit for engineers who are familiar with tuning a particular brand of servomotor, retrofitting machines with existing motors on them, or meeting specific factory standards.

Key differentiators, according to Haury, include high thrust capacity, heavy wall steel construction, rugged piston anti-rotation, and high dynamic capacity ballscrews. For more information on Eliminator HD check out www.edrivedesign.com/eliminator.html, where you'll find images, specs, and graphs of life vs. load and torque vs. thrust.

The Ternary linear (TLS) electromechanical actuation system from Alpha Gear Drives Inc. targets pneumatic cylinder replacements, and underscores the company's role as a solutions provider rather than a component manufacturer.

Ternary three-in-one actuator products combine electronics, software, and mechanical technology, explains alpha Applications Engineer Bill Dorman. "So engineers don't have to spend a lot of time getting it all to play together." TLS uses a ballscrew and nut for linear motion. But the heart of the all-in-one system is a stepper motor with integral drive and controller.

Operating in closed loop with feedback from an 800-ppr encoder on the back of the stepper, "the unit achieves servo-like performance at low cost," Dorman explains.

Two modes of operation, local and direct-drive, offer designers flexibility. "Up to 16 positions in local mode can be saved and combined with acceleration and velocity parameters," he says. "And for motion sequences with an infinite number of positions, engineers can set the intelligent actuator up as a slave to a host PC or PLC in direct-drive mode." For more information visit www.alphagear.com.