Power transmission rocks on at NDES

The ELCOM ST(tm) slotted brushless dc motors from Pittman (http://www.pittmannet.com/300000.html?id=188) now include control electronics inside the motor housing. The company claims the result is a smaller, more versatile motor that's less expensive to operate than conventional brushless dc motors that typically require more complex connections.

The motor's flexible design allows Pittman to configure it as either a two-wire, single-polarity motor with open-loop speed control, or as a reversible motor just by changing the windings. The company can even incorporate other functional components such as closed-loop motor speed control, and encoders for velocity feedback and enhanced motor stability.

Targeted at engineers seeking the simplicity of a motor with on-board electronics, but without the expense of an indexer on each axis, the IMS Motor+Driver from Intelligent Motion Systems Inc. (http://www.imshome.com) consists of a NEMA 17 frame size 1.8-degree motor mounted to a microstepping motor drive. It's also available in multiple configurations, including a single-shaft stand-alone device, a standard motor with optical encoder, and an Acme screw linear actuator.

"With prices starting at $113.73 each/100 piece quantity, it allows the system designer to choose the best method of control for the application," says IMS President David Coutu. Various setup parameters can be changed on-the-fly or downloaded and stored in non-volatile memory. And the motor is available in three different stack lengths. "It's a small, powerful, and inexpensive solution that offers 'cost-effective versatility,' and reduces design and assembly time in low-power stepping motor applications," says Coutu.

Designed for limited space applications, the series 44M100D permanent- magnet stepper motor weighs in at just 80g (2.82 oz), but it's no lightweight in terms of power, according to Thomson Airpax Mechatronics (http://www.thomsonindustries.com/airpax/airpax.htm). Its "super-thin" design measures just 44 mm (1.7 inches) by 12 mm (0.48 inches) long, yet it produces 30 mNm (4.25 oz-in) of pullout torque.

Engineers designing electronic assembly equipment such as component delivery systems, tape and label feeders, and precision-testing instrumentation will appreciate its super-thin profile, high torque to inertia ratio, and low cost of $9.95 for 500 units. Flexible options include custom mounting/lead egress positions, changes in coil design, and different bearing configurations.