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Name: Moe A.
Status: Other
Age: Old
Location: N/A
Country: N/A
Date: May 2004

Are there any advantages of this design over a squirrel- cage to justify the higher cost, or was this a predecessor of the squirrel-cage design?

It is pretty clearly a gimmick to add startup torque to an induction motor. Purely symmetric AC induction-motors have zero torque when at zero velocity. Shaded-pole motors have this symmetry broken a bit, but the startup torque is still too weak if there is a viscous or heavy load on the rotor. Capacitor-start motors sound like the nearly equivalent thing today. I cannot compare advantages in detail, but I tend to think your motor's characteristics are somewhere between capacitor-start and shaded-pole. I do not know the history.

Jim Swenson

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