Pole arrangement for synchronous electric motor - has opposed pairs of stator poles chamfered at air gap region to improve running action of rotor

摘要

The synchronous electric motor is for control and measuring purposes and also for the drive for a labelling machine or for an indexing drive. It has a permanent magnet rotor (7) with poles which are two less in number than the pole pieces carrying the windings (8, 9) for the stator. Thus the rotor can have six poles and the stator has eight. Two (3) adjacent stator poles are chamfered at one side, and the two stator poles opposite them are also chamfered. This increases the air gap, and the chamfers of each pair are on the outer corners. This improves the running action of the rotor, and when the power supply is cut off, there is a stronger holding force on the rotor.