Ha, interesting. You’re saying the coils were D shaped in the direction of rotation, not aligned inwards or outwards. Well hard drives only turn in one direction, so that makes sense. But also, they have to turn at a very constant speed, and the load is very, very small. So I wonder if the coils were shaped that way to smooth out the torque the motor applied.
Could permanent magnets be shaped asymmetrically, and make a directionally biased motor?
I’d say it’s because a lot of people don’t trust “weird” tools and simply want a simple tool. If they don’t understand how it works, they shun it. I’m the opposite.
yes permanent magnets which is a little misleading a name. but yes a directional magnetic field. I think people might be hung up on the idea that a there is a north and south pole of the magnet and that it’s evenly divided.
This is not always the case. The motors we made had magnets that were formed ceramics (most magnets today are) where in the mix is the “rare earth” magnetic metals. The formed ceramic when delivered to the factory was not magnetic at all. But once in the motor the drum would go into a magnetizer which was a coil system and it not only magnetized them but it also introduced a coil like shape to the magnetic field - it wasn’t just end on end it had a twist to it.
Those motors then produced more torque in one direction than in the other - all had to to with the field… The motors were used as window lift motors. I guess my big point here was not don’t think of the magnetic field as just north and south in a line like in those bar magnets from school days. It can be quite complicated.