The TMK line of torque motors from ETEL, a Swiss firm (www.etel.ch), has 30% more torque (on average) and top speed has been increased by a factor of 3.5 compared to the design of traditional torque motors. The extra torque comes courtesy of the motor’s flux-concentrating structure. And the increased speed is due to the laminated rotor and improved design of the rotor teeth.

The motors come in 12 standard sizes ranging from 198 to 385 mm in diameter and peak torque can be as high as 2,240 Nm. Top speed is 5,170 rpm with peak force density of 10 N/cm2.