Title:
INDUCTION MOTOR
Document Type and Number:
Japanese Patent JPS555045
Kind Code:
A
Abstract:
PURPOSE:To eliminate the variation of the rotation of an induction motor even after its frequency is altered at constant load and voltage by providing a secondary resistor of large resistance. CONSTITUTION:A shorting ring 3 is provided at both ends of the slot 2 at a cage rotor core 1 of an induction motor to increase the secondary resistance thereof. The resistance is reduced by decreasing the sectional area of the shorting ring 2, or the slot 2 or reducing the purity of aluminum material of the slot 2 and the ring 3 or replacing the aluminum by zinc with low conductivity. Thus, the secondary resistance is continuously varied to set the secondary resistance for obtaining the same rotating speed of the motor at both 50Hz and 60Hz. Thus, even if the frequency is varied at constant load and voltage of the motor, the rotating speed of the motor can be retained constant, and the variation of the speed can also be eliminated against the voltage variation of approx. + or -1.0% of rated current as shown in a graph.
Inventors:
NEGISHI KOUSABUROU
Application Number:
JP7678178A
Publication Date:
January 14, 1980
Filing Date:
June 23, 1978
Export Citation:
Assignee:
SANKYO DENKI CO LTD
International Classes:
H02K17/16; H02K17/30; H02P23/00; H02P25/04; (IPC1-7): H02K17/30; H02P7/36
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