A magnetic bearing is a bearing that supports a load using magnetic levitation.
Magnetic bearings support moving parts without physical contact. For instance, they are able to levitate a rotating shaft and permit relative motion with very low friction and no mechanical wear. Magnetic bearings support the highest speeds of all kinds of bearing and have no maximum relative speed.
In Constant Mesh Gear Box all the gears are always in mesh and the engagement between the gears which are freely rotating on the transmission main shaft or output shaft and the layshaft is effected by moving the dog clutches.
If anyone of the gears on the layshaft is coupled up to the mainshaft then there will be a driving connection between the mainshaft and the engine shaft.
The coupling is affected by the dog clutch units.The dog clutch members are carried on splined portions on the mainshaft.
Dog clutches are free to slide on the splined portions , but have to
revolve with mainshaft.