The latest range of Parker’s torque motors is designed with the aim of helping end users of heavy-duty industrial machinery replace traditional motors and gearboxes with a highly efficient direct-drive system.  Used together with Parker’s variable-speed drives, the torque motors are intended primarily for use with plastics and rubber extrusion machines, as well as with injection molding, mixing, crushing and winding equipment.  The new motors can help reduce energy and maintenance costs, thus improving productivity and profitability, and providing greater reliability and overall levels of performance.

A lot of high-power machines use AC or DC motors linked to gearboxes to provide the required torque and speed to drive screws, shafts and other associated components.  However, this configuration can be noisy and unreliable, draw relatively high levels of power, and also be complex to install, operate and maintain.

In contrast to the configuration described above, the new Parker TMW series torque motors are based on a proven design of permanent-magnet, brushless servo motor, which produces high levels of torque at low operating speeds.  Used in combination with Parker AC890 variable-speed drives, this enables a screw to be connected directly to a motor, with speed and torque being controlled by the drive.  Unlike traditional gearbox systems, this allows operating parameters to be varied infinitely within the performance envelope of the motor.  This is a far more efficient process, seeing as there are virtually no power losses in the transmission mechanism, which helps to reduce energy consumption and stress on moving parts within the system.  The TMW motors are virtually noiseless, have a far smaller footprint, can be retrofitted easily and require only minimal maintenance.

Unlike some other torque motors on the market, Parker’s TMW range features an integrated thrust bearing that can be sized according to the application, as well as an innovative screw extraction mechanism to simplify installation and maintenance.  Parker is also able to offer both standard and customized mechanical interfaces for shafts and barrels, with the shaft being hollow to improve cooling.  The TMW range can be used with machinery requiring from 1200 up to 22,000Nm of torque and running at speeds of 50-500rpm.  It is estimated that the typical efficiency improvements from a TMW motor and AC890 drive combination is up to 10 per cent better when compared with a traditional gearbox based system.