CIRCUITO DI CONTROLLO A COMMUTAZIONE PER MOTORI, IN PARTICOLARE PER MACCHINE LAVABIANCHERIA

The present invention relates to a switching control circuit 7 for direct or alternating current motors, particularly for washing machines. According to the invention, this circuit has, in combination: a) means 8 capable of determining the number of revolutions of the motor and of generating an electrical signal V2 according to this determination; b) an error amplifier 20 capable of amplifying an input signal V3 given by the resultant of the aforesaid electrical signal V2 and a signal VR representing a desired number of revolutions of the motor 1 set by means of a programming unit, the said amplifier 20 generating an output signal V4 which is compared with a signal Vp representing the power absorbed by the motor network 1; c) amplifier means 25 for amplifying an input signal V5 given by the difference between the signal V4 at the output of the error amplifier 20 and the signal Vp representing the power and for sending a drive signal V6, the latter being sent to a modulator means 27 capable of controlling at least one solid-state switch 5 in series with the motor 1.