POSITIONING CONTROL DRIVE UNIT

摘要

The position adjustment drive is particularly for a sewing machine, having a micro-processor set of at least 8 bits. from which different operating sequences can be separately derived. To control the speed of rotation there can be a phase-locking unit functioning as a three-point regulator, the unit having an oscillator with voltage control followed by a comparison stage acting as a phase comparator, from whose output a back-coupling loop leads to the voltage-control input of the oscillator. A filter can be mounted in the loop, to reduce the back- coupling effect at high frequencies.