Permanent-magnet synchronous motors, which are also known as torque or high-torque motors, are rapidly becoming established as the standard solution for more and more applications – and now also in mixing technology. Combined with a compact and space-saving design that only requires very little installation space, the high torque output of these drives enables energy-efficient solutions for challenging mixing tasks.
Mixing drives with asynchronous motors, which have been commonly used for many years, come with restrictions. Usually, the rotational speed of the motor is not the same as that of the mixing tool. In order to obtain the most suitable mixing speed for the mixing task, gearing ratios are normally realized with the aid of V-belt drives, or gearboxes are used for applications with a high torque demand to translate high motor speeds into low tool speeds.
Increase of the magnetic field by 20 %
Mechanical transmission elements such as V-belts and gearboxes are subject to wear, so regular inspections and maintenance are essential. When torque motors are used, these transmission elements are no longer required. The mixing tool is then connected directly via a flange to the motor shaft of the torque motor, and the power transmission is direct and loss-free.
The use of torque motors offers many advantages: less weight, more power and minimized losses improve efficiency and dynamic performance. Thanks to the omission of a number of mechanical elements, torque motors are low-noise and low-maintenance. Due to the increased stiffness of the drivetrain, vibrations are reduced and the motor runs more smoothly. There is virtually no wear at all in the motor, partly also because there are no radial belt forces.
Higher efficiency of the
Torque drives can initially appear more expensive due to the higher purchase cost of the motor including the frequency inverter. However, if the costs of the components for the belt drive and the gearbox that are required for drives with asynchronous motors are included in the cost assessment, the additional costs are relativized. Depending on the particular application, a torque drive can be fitted to a new machine with almost no additional cost.
Torque motors have also been the standard technology for large-scale mixers. The excellent energy efficiency, low maintenance requirements and long service life of the mixing tool drives have already inspired customers to convert older mixers to the new drive system.