History of Magnetic Bearings
Permanent magnets and magnetic effects have been fascinating people ever since they have been discovered. From the discovery that magnetism creates forces without mechanical contact to the idea to use this effect for a magnetic bearing, however, some time had to pass.
- Ancient scientists discover the magnetic effect in natural magnetite minerals as early as 600-400BC.
- In the 12thcentury, the compass is used by many Chinese sailors
- Hans Christian Oersted discovers in 1820 rather accidentally, that the flow of electric current influences the needle of a compass. The connection between electricity and magnetism was found.
- In 1842, Samuel Earnshaw publishes his famous article “On the Nature of the Molecular Forces which regulate the Constitution of the Luminiferous Ether” (Earnshaw’s Theorem) on the force equilibrium in static fields. Werner Braunbek interprets the theorem 1939 in the sense of magnetic levitation, showing that purely permanent magnetic stabilization of an object is only possible using diamagnetic materials.
- Jesse Beams uses active magnetic bearings for the development of uranium centrifuges within the Manhattan Project in the 1940s. The patent “Suspension of Rotatable Bodies” is filed.
- With growing computing power and the development of relatively small processor units, international research in magnetic bearings starts increase in the late 70s and 80s of the 20th century.
- Around the same time, first industrial magnetic bearings are used in turbo machinery and high-speed vacuum pumps.
- In 1988, the first International Symposium on Magnetic Bearings (ISMB) is held in Zurich, Switzerland. Since then, the Symposium attracts the scientific and industrial contributors every 2 years. Find a list of the past symposia here.
- Today, magnetic bearings have found their way into many applications where they push the limits or even allow completely new approaches to bearing problems.