DRIVE CABLE DRUM Russian patent published in 2021 - IPC B61B9/00 B66C13/12 B66D1/12 B66D1/30 

FIELD: lifting devices.

SUBSTANCE: present invention relates to lifting-and-conveying equipment, in particular to devices for unwinding and winding of cable on drum during lifting or movement of crane. Segments of magnets 7 are started to rotate in drive cable drum at rotation of engine 1, thus inducing Foucault currents in disc 8 to form magnetic field interacting with constant field. As a result, asynchronous rotation of disc 8 relative to magnets 7 of sign-alternating polarity is provided. This ensures smoothly tensioning cable 5 regardless of whether it is winded on the drum, or unwinding from drum 4, or starting the drive cable drum in operation. Three-phase frequency converter 9 performs the following functions: automatic regulation of tension uniformity during winding and unwinding of the cable with a drum; frequency converter, in real time, maintains the required torque on the shaft of the electric drive of the cable drum; control of winding speed or cable unwinding by a drum, as well as increase in speed adjustment accuracy. Variable speed of winding or unwinding cable by drum is change of current flowing through windings of three-phase motor 1: when current increases, frequency of three-phase voltage supplied from converter 9 to engine 1 decreases, which starts to rotate at lower rpm per unit time; at reduction of current frequency of three-phase voltage supplied from converter 9 to engine 1 increases, which starts to rotate with high speed in unit of time.

EFFECT: higher operational reliability of drive cable drum.

1 cl, 2 dwg