Mini-motor lasts longer
API Motion's 17S 17-mm miniature brush dc motor series is based on Potescape's ironless-rotor concept that minimizes both power losses and rotor inertia. A precious-metal commutation system uses gold-alloy brushes and silver-alloy collector materials to increase efficiency and extend service life. "Motor life increases up to 50% because our patented Electro-Erosion Reduction (EER) system decreases the number of wear-causing sparks and peak currents in the commutation system," says Product Manager Steve Veya. The 18.7-mm long motor achieves almost 0.011 Nm of stall torque.
Targeted at battery-powered devices such as medical pumps, security cameras, and model trains, the motor starts at $33/unit list.
Less copper = more torque
Rockwell Automation enters the high-performance servomotor fray with its MP Series servomotors. The brushless permanent-magnet type motors use a segmented-core design that conserves copper compared to the company's induction motors, while achieving higher copper density inside the motor. Instead of winding the motor stator all at once, a segmented core allows the manufacturer to wind each slot individually prior to stator assembly. The result, according to Senior Product Marketing Engineer Rod Dorschner, is higher copper density, flatter end turns, and approximately 40% more torque for its size. Targeted at packaging equipment and applications where space is an issue, the MP Series will be available in a broad range of sizes from IEC 55 to 150, with torque ranging from 0.5 to 100 Nm.
Analog speed control board
The OSC-462H from Intelligent Motion Systems Inc. uses a digital oscillator for accurate velocity control with an output frequency of up to 100 kHz, which varies the level of the 0- to 5V dc input via a 10-kV potentiometer. "Compared to traditional voltage-driven oscillators set up with resistors and capacitors," explains IMS President David Coutu, "crystal-driven oscillators have negligible frequency drift over time and temperature changes, for more stable operation." The stepper motor speed-control board uses a 10-command instruction set that consists of 2 to 7 character mnemonics. An operator interface plugs into the board for parameter set up and downloads into flash memory. Priced at $64.50 each in quantities of 100, the programmable single-axis device targets simple point-to-point, constant-frequency applications.
Force with finesse
Need to replace hydraulics? E-Drive Design's Eliminator HD(TM)series heavy-duty ballscrew linear actuator offers four frame sizes with thrust capacities from 2,000 to 24,000 lb, and linear velocities up to 23 inches/sec. 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 Sales & Marketing Manager Jim Haury. "And the Eliminator HD accepts virtually any motor/gearhead to accommodate retrofits, engineer preference, and factory standards." Key differentiators: high thrust capacity, heavy steel wall construction, rugged piston anti-rotation, and high-dynamic-capacity ballscrews.
PCI-bus and 4x the power
In addition to ISA, the Unidex 500 family of multi-axis controllers now comes in a PCI-bus format. Enhancements to the eight-axis motion-control card include upgrading D/A converter resolution from 16 to 18 bit; increasing encoder-input frequency from 20 to 40 MHz; and adding I/O (up to 48), according to Chief Engineer Alex Weibel. "We have more processing power to achieve faster update rates," he says. In fact, the Unidex 500 series controllers achieve a minimum servo update rate of 62.5 msec using the Motorola 56300 DSP controller. But it's the Position Synchronized Output (PSO) function for laser firing or data acquisition that really makes this product useful to design engineers, Weibel says. "Now engineers can generate pulses at either fixed increments or varying increments based on encoder position," he explains. "And they can specify the output-pulse width."
With its new Ternary linear (TLS) electromechanical actuation system, Alpha Gear Drives Inc. underscores its role as a systems provider rather than a component manufacturer. Ternary products combine electronics, software, and mechanical technology, so engineers don't have to. Targeted at pneumatic cylinder replacements, TLS uses a ballscrew and nut for linear motion. But the heart of the all-in-one system, according to Applications Engineer Bill Dorman, 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," explains Dorman. 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," says Dorman. "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."