magnetic coupling

Yes, there is that way, but there is also Eddy current coupling, whereas you have 2 electro magnetic coils, by the poles, you will get a attraction and repulsion

So 1 disk having N-S-N-S and the 2nd disk having the same poles, the opposites attract, with low magnetic flux, you will have high slippage, increasing the current into the device you will have stronger magnetic fields, so the "grabbing force" between the 2 "Rotors" will be greater, and less slip will be induced.

Look up "Eddy Clutch"

TECO manufacture a "Eddy Clutch Controller"

This type of clutch is used for the transmission from a single speed motor (Prime mover) to a load that needs variable speeds, and also in Chassis/Engine Dyno's

Dear Sir

I add to your comment:

Mostly "Magnetic-Clutch's" both the plates are Hermatically-separated so the chemical pumps could function without having some jiont in chemical-line as in old-photo-film-processors , by Kodak.

I am out for last 20 years, how new models work?

Regards

Dear Sirs

Further to my in post #4:

This type of clutch is a Slipping-Clutch & no wear-tear in both parts.

The type I referred to "No-Hydrics coupling & NO Hydrics leakage.

Driving motor's Output Shaft-coupling fits in Round-way in Pump having clearance around

& the pump fitted on drive motor. Kodak was the major user in film-industry in 1970s.

I was maintaing their processors used in Public Hospitals' X-Ray departments.

Regards

You have to go to your physics book and look up electric motor torque (or at this link).

Basically in an induction motor the stator has current that runs through it. This stator current has a magnetic field that is a consequence of current flow (right hand rule). That stator magnetic field induces a current in the coils that reside in the rotor. The current induced in the rotor coils has a magnetic field that tries to oppose the stator magnetic field. This has a phenomenon called torque and it can be calculated with cross products from calculus. Anyway it's like if you try to hold two magnets together at the same poles and they try to go away from each other.

Cheers,