Switchable Magnets.

[synchro1]

This video from "K&J Magnetics" shows 400 pounds of force switched on and off:

https://www.youtube.com/watch?v=DPwoFnQnBPk

More information:

http://www.kjmagnetics.com/proddetail.asp?prod=MS-400

It looks like it takes a lot less then 400 pounds of force to throw the lever!

[truesearch]

@synchro1:


That is very interesting! Any idea how it's being done? Apparently without electricity. . .


truesearch

[synchro1]

@Trusearch,

The bottom photo's the "Off" position. Just simply two diametrics with steel side walls!

"Now, the cool part about a Magswitch® is that you can turn it OFF.  Here's where the magic happens.

When you rotate the knob, you're rotating the top diametrically magnetized disc magnet by 180°.  Now the magnetic field flows from one magnet, through the steel wall and into the other magnet.

The folks at Magswitch® must have done their math right, because the steel structure is shaped and sized just right to keep all of the magnetic field flowing inside the assembly.  It doesn't reach outside at all!  In this position, no pull force is felt.

We've tried it ourselves, and these powerful magnets won't even pick up a single paperclip in the OFF position".

[truesearch]

@synchro1:


Your explanation does sound like what is going. Does that main that it takes "real" effort/force to switch from NON-ATTRACT to ATTRACT mode? I'm guessing that would simply because of the "top" magnets rotating to a REPULSION-POLE-TO-POLE arrangement in regards to the "lower" magnets. . ?? . 


truesearch

[lumen]

It must be in contact with steel to rotate easily to the on position.