 Why adopt torque motors?
 REDUCED COST OF OWNERSHIP
Direct coupling of the payload to the rotor eliminates the need for mechanical transmission elements such as gearboxes, timing belts, speed reducers and worm gear drives. Unlike brushed motors, there is no contact by the moving parts in a direct drive system. Therefore there is no mechanical wear resulting in excellent reliability and long lifetimes. Fewer mechanical parts minimize maintenance and reduce the system cost. The direct drive technology intrinsic to a torque motor based system results in an efficient and effective gearless assembly.
EASY INTEGRATION
ETEL torque motors are available in a wide range of sizes and can be easily adapted to most applications. ETEL’s unmatched standard product offering includes motors with external lamination stack diameters up to 1260 mm. The limited airgap inherent to direct drives results in a large hollow shaft for easy integration of cables, cooling tubes or other equipment. The ring configuration of a torque motor minimizes the volume required for mounting. This gives the machine designer great flexibility in locating the motor with respect to support bearings, feedback devices and payload.
DYNAMIC PERFORMANCE
Torque motor applications have a wide range of dynamic performance requirements. Depending on the specifics of a system’s duty cycle, the peak torque, continuous torque or both will drive the selection of a motor. An application with a light duty cycle that requires high peak torque for a short period of time will typically utilize an uncooled motor like ETEL’s TML series. As the continuous torque requirement increases so will the temperature of the motor. The integrated cooling in the ETEL TMB and TMK motors provide an efficient means of temperature control ensuring high dynamic performance that can be maintained even for the most demanding applications.
WIDE TORQUE-SPEED RANGE
Direct drive torque motors deliver high torque over a wide range of speeds, from a stalled or low speed condition to high angular velocities. Torque motors can achieve high velocities (up to 5000 rpm) with a trade off in torque as technology becomes limited by eddy current loses in magnetic field.
The torque motor is part of a complete direct drive solution which includes a position controller. Servo controllers like the ETEL position controllers that have been designed specifically for direct drive applications provide excellent control loop quality ensuring optimum stiffness, smooth motion and excellent velocity control with low torque ripple. |
