Textile machines consist of a huge amount of spindles, e.g. ring spinning machines have up to 1200 spindles. Even today most of these spindles are belt driven by one central motor in the textile machine. Merely spindles with high power requirement - e.g. cabling machines - are provided with inverter fed induction motors. But these are most often drives with a common frequency converter, feeding a common three phase AC link. Both types of spindles, the belt driven and the induction motor driven, need additional sensors to monitor the work of the spindle - e. g. speed sensors or sensors to detect the breakage of a filament.
An `intelligent' single spindle drive could take over the functions of these sensors, reduce noise and save energies. The textile machine would become more flexible with the ability to controll each spindle separately.
The main demands are small processing costs and a high degree of efficiency. Furthermore, a speed control is required, as well as a communication interface to the controller of the textile machine. The electronic devices should be integrated into the motor housing. The substitution of external sensors requires the measuring of the shaft torque , .
The main demands on the drive are: