A recent microdrive called the penny motor, and for good reason, may be useful in getting designers to think small. “Although the brushless motor measures only about 12-mm diameter by 2-mm thick, it uses high-precision ball bearings, multipolar rare-earth magnets, and a coil made by photolithographic processes,” says Matthias Nienhaus, director of the company mymotors and actuators, Germany. “These motors could be used as direct drives in scanners and ventilators, in micro pumps, or high-precision positioning and dosing systems,” he says.

Nienhaus says the company focuses on drives, controllers, and accessories, such as cables and plugs, all of which have been downsized. The company recently developed two-gear motors with a flat design capable of many gear ratios. “These can generate considerable torque, up to 10 mNm,” adds Nienhaus.

Position sensors are also available for the motors. The company's goal is to expand the range of sensors and enhance the level of “intelligence” in micromotors. The devices are available in the U.S. from MicroMo Electronics, Clearwater, Fla., (www.faulhaber-group.com/mymotors).