INDUCTION MOTOR WITH SHORT-CIRCUITED ARMATURE AND A PIPE CAGE.

摘要

Induction motor with a short-circuited armature and a pipe cage at which the rotor bars protrude beyond the frontal side of the rotor at one or both ends thereof and on the protruding bar ends short-circuiting means are arranged. In the bar section between the short-circuiting means and the frontal side of the motor, at least on one side of the rotor short-circuited tubes made of a magnetizable material are placed on each of the rotor bars insulated from the rotor bars. The wall-thickness of said tubes is selected in such a manner that partly they should reach or at least approximate the state of magnetic saturation under the influence of starting current, partly the Skin-effect should arise in them. The excitation and plus-slippage occuring at the operational speed of rotation may be eliminated, when the tubes are provided with one or more slits forming air-gaps in longitudinal direction, preferably along the external and/or internal generatrix.