Abstract: Thread-guiding device for apparatus for winding a thread onto a support rotatable by associated actuating means, at least one element for receiving and guiding the thread to be wound, the element for receiving and guiding the thread to be wound being integral with a thread guiding device of the magnetic/electromagnetic.

Abstract: This invention relates to a circuit and to a method for processing amplitude and phase variable multiphase signals, which are required as current or voltage reference to drive electric motors, comprising a synchro-resolver angular position transducer, rigidly connected with a synchronous motor with the same polar configuration and number of poles thereof, according to which the analog signals detected by said transducer are modulated, demodulated and outputted out of phase by 90.degree. with the signals relating to the rotating magnetic field. The circuit moreover comprises a phase shifter device and means for modifying the amplitude of signals out-putted by said transducer as a function of at least one control signal. The resultant of the signals processed by said means is supplied to an amplifier to generate in the stator currents of determined amplitude and phases for driving said motor complying with the magnetic laws thereof.

Abstract: A chopping transistor connected across a d-c power supply, in series with a load such as a motor, has its base connected to an output of an oscillator generating a train of voltage pulses V.sub.1 by which that transistor is alternately turned on and off. A threshold sensor emits a series of monitoring pulses V.sub.2 of the same polarity as the conduction-establishing control pulses V.sub.1 when the collector/emitter voltage of the transistor surpasses a certain limit; the joint appearance of signals V.sub.1 and V.sub.2 at respective inputs of an AND gate gives rise to an off-normal signal V.sub.3 which, if of extended duration, passes a delay circuit to act as an alarm signal V.sub.4. A memory tripped by that alarm signal emits a permanent disconnect signal V.sub.5 which either blocks the oscillator or fires a thyristor in shunt with the transistor whereby a fuse in series therewith is blown.