Rotor of permanent magnet motor

Abstract

The invention discloses a rotor of a permanent magnet motor. The rotor comprises a rotor core with a plurality of installation grooves and permanent magnets installed in the installation grooves. The rotor core is provided with a central hole and a plurality of sections of cylindrical surfaces, a magnetic bridge is connected between adjacent cylindrical surfaces, the outside surface of each magnetic bridge is much closer to the central hole of the rotor core relative to the cylindrical surfaces, the outside surface of each magnetic bridge is outwards concave from the installation grooves to form a groove in the magnetic bridge, and the widths of the grooves are smaller than that of those of the installation grooves. Compared with the prior art, the rotor of the permanent magnet motor has the advantages that the magnetic bridges and the grooves are arranged to allow a motor with the rotor to obtain low cogging torque, reversed electromotive force tending to the sine and low load torque pulsation. The rotor has the advantages of being simple in manufacturing process, high in mechanical strength, low in noise and high in demagnetization-resistance performance due to appropriate multi-section arc or the line-section magnetic bridges, and the rotor is applicable to motors of roller washing machines.

Description

technical field [0001] The invention relates to a rotor of a permanent magnet motor, in particular to a rotor of a permanent magnet motor applied to a washing machine. Background technique [0002] At present, most of the drum washing machines use series-excited brushless motors and outer rotor brushless motors. For example, Chinese Patent Application No. CN200720110566.5 discloses a motor. The structure of the series motor is complicated. The rotor current is mechanically commutated through the commutator and brushes. When the motor is running, especially dehydration, it runs at a high speed. High-speed friction occurs, which causes the motor to have large mechanical wear, high noise, strong electromagnetic interference, and easy to generate sparks. [0003] Chinese patent application number CN200580041295.6 discloses an external rotor motor, which is assembled by a cantilever beam, and the imbalance of the external rotor causes the noise of the motor to be large. [0004...

AI Technical Summary

Problems solved by technology

For example, the Chinese patent application number CN200720110566.5 discloses a motor. The structure of the series motor is complicated. The rotor current is mechanically commutated through the commutator and the brush. High-speed friction occurs, which causes the motor to have large mechanical wear, high noise, strong electromagnetic interference, and easy to generate sparks

[0003] Chinese patent application number CN200580041295.6 discloses an external rotor motor, which is assembled by a cantilever beam, and the imbalance of the external rotor causes the motor to be noisy

[0004] Furthermore, Chinese Patent No. CN201020145709.8 announced on June 22, 2011 discloses a motor, the motor is a built-in permanent magnet motor, the end of the permanent magnet on the rotor is provided with a groove, the groove has a gap, the gap Make the slot communicate with the outside of the rotor, and fill the slot with polyester, the process of the permanent magnet motor is complicated, the mechanical strength is low, and the rated speed of the permanent magnet motor is low

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