Actuators with built-in controllers
A line of computer-controlled linear actuators, linear slides, rotary stages, mirror mounts, and other motion control devices offer flexibility in automating submicron positioning applications. Because the devices have built-in controllers, they need only be connected to a computer’s serial or USB port to be ready for use. Additional devices can be daisy-chained to the first and controlled via the same port. Linear actuators to suit a wide range of application requirements are available, offering capabilities that can be matched with needs for thrust, resolution, range, or vacuum compatibility.
Zaber Technologies Inc., Richmond, BC, Canada
Easy-to-install spring-set electromagnetic power-off brakes with a built-in quiet feature are designed to provide safe and energy-efficient braking in such applications as medical equipment, robotics, actuators, motor systems, and packaging equipment. The Thomson-Deltran AKB–series brakes come in diameters of 1.83–5.00 in. and provide static engagement with torque of 12.5–470 lb-in. The brakes’ field assembly is fixed and unable to rotate, while the rotor assembly is secured to the shaft; the shaft rotates freely when the coil is energized. But when power is off, the fixed and rotating components engage, stopping or holding the load.
Danaher Motion, Wood Dale, IL
Air cylinders with a twin-rod design are offered as a means of achieving precise, nonrotating linear motion while producing twice the force of conventional cylinders of their size. Exhibiting less than 1/3° of rotation, the design ensures precise rod alignment and essentially eliminates end play. The rectangular cylinder body simplifies mounting, saves space, and facilitates the achievement of precise angles. The rod end plate accepts other pneumatic devices. Available in single- and double-acting models, the cylinders come with finely adjustable 1/2- to 4-in. strokes and in six bore sizes ranging from 1/4 to 1 1/4 in.
Humphrey Products Co., Kalamazoo, MI
Brushless dc motors
A family of brushless dc motors is offered for space- and cost-restricted applications such as pumps, fans, and medical devices, and especially for uses where long life, high power density, high starting torque, and controllability are required. With a 1-in. outside diameter and lengths ranging from 0.5 to 1 in., the BLDC25-OR-series three-phase motors include three Hall-effect sensors for exact positioning and smooth running. Their 12-pole design makes positioning feedback of 36 pulses per revolution available without an additional encoder. The motors can produce continuous maximum power of 3 W and efficiency values above 70%.
Hansen Corp., Princeton, IN
Incorporating an optical linear encoder and linear motor, a rigid, compact positioning actuator that features patented curved-cage technology is designed for high speed, high accuracy, and long-term maintenance-free operation. Its direct-drive design and fully closed control give the Type KLM actuator a positioning accuracy of 10 µm/500 mm and positioning repeatability of ±0.3 µm. The actuator operates at speeds to 2.0 m/sec and with accelerations reaching 4.7 g. The Caged Ball linear motion guide that gives the device its speed and accuracy capabilities provides lubrication, smooth movement, low noise, and low dust generation.
THK America Inc., Schaumburg, IL
Digital servo amplifier
A high-voltage, all-digital brushless servo amplifier uses a digital-signal-processor-based architecture and provides software-selectable torque-, velocity-, or position-mode operation. Sine-wave commutation enables the compact ACE500 motor controller to deliver smooth torque at low speeds for demanding motion control requirements in robotic, direct-drive, and linear-motor applications. The amplifier uses an ac flux vector control algorithm to provide high dynamic response and very good noise immunity; its low current harmonics ensure smooth, efficient motor control. The 6.9 × 5.2 × 1.95-in. device handles power inputs of 90–254 V ac, single-phase, and 120–360 V dc.
Automotion Inc., Ann Arbor, MI