Combining Forces

Motor technology is moving ahead with higher power efficiency, servo motors with integrated electronics and a continuing commitment to Ethernet communications and distributed intelligence at the top of the list.

Compactness and lower costs are also important priorities, as suppliers look to deliver speed and torque in packages that reduce overall system costs and simplify applications development. For motors of all types, from micro motors to large ac motors, improved power density and consistent high levels of dynamic performance are vital for new motion control applications.

“Direct torque, interior permanent magnet motors and energy efficiency are the main trends that we see,” says Mark Crocker, European marketing director for Baldor. “There also seems to be a lot of interest in integrated motors. We have had an integrated induction motor product for some years, and stepper motors with integrated electronics, but there is growing interest in servos with integrated electronics.”

Higher resolution feedback is also becoming increasingly popular, as cost-effective solutions have been introduced. For years, feedback devices were either proprietary or cost prohibitive but now technologies such as BIS are providing performance, lower costs and absolute feedback, as well.

Smaller, cheaper and higher power densities continue to be the main focus of ongoing product development. Ethernet networking is making a big difference in enabling high axis count applications and is helping drive the usage of servo motors.

According to Dan Throne, sales and marketing manager for Bosch-Rexroth, motor technology has shown significant increases in overall feedback options resolution and increased intelligence in the motors. Motor sizes are shrinking while the power density is improved and the cost of feedback and overall costs are dropping.

“Rotary, frameless and hollow shaft motor technologies are making the motor line derivatives of traditional motors,” Throne says. “We are doing more hollow shaft motors where the motor is an integral part of a nip roll because it makes no sense to have a gearbox, belt and pulley or ball screw. There is a tighter integration between the machine and motor technologies, versus what we accomplished with traditional motors.”