vacuum cleaner circuit

Using a vacuum cleaner to clean a room is not only clean, hygienic, labor-saving, time-saving, and effective, but its biggest advantage is that it can effectively absorb dust
so that the dust will not spread and fly, keeping the indoor air clean. The many advantages and applications of vacuum cleaners have gradually been understood by consumers.
With the gradual improvement of people's living standards. Vacuum cleaners have been widely used in households.
    Figure 1-28 shows the circuit of the Chunhua brand XDL-60 upright vacuum cleaner . In Figure 1-28, S is the manual switch. L is the inductor coil, VTD
is the bidirectional trigger diode, and VTH is the bidirectional thyristor. RP is the speed regulating potentiometer. Turn on the power and press the switch S. When the voltage across C2 reaches
the turning voltage of the trigger diode VTD, VTD is turned on, cz is discharged, and the pulse current flows through the gate of the triac VTH and is triggered to conduct,
thereby starting the motor M. By adjusting the potentiometer RP, the phase of the gate trigger pulse can be adjusted to change the conduction angle of VTH, thereby adjusting the motor
voltage and controlling the speed of M to achieve the purpose of changing the suction power of the vacuum cleaner . Island and Ca form a surge voltage absorption circuit to absorb
the higher surge voltage generated at both ends of VTH when the motor M commutates.