3899979 is referenced by 40 patents and cites 8 patents.

Permanent magnets and electromagnets are secured to one another, endwise, to provide for magnetic suspension of a vehicle. The combined magnets are maintained attracted to a track, across a narrow air gap. The magnet arrangements are such that the attractive, magnetomotive force is provided mainly by the permanent magnets. Electric current for energization of the electromagnets is supplied exclusively, or mainly, to keep the air gap clearance substantially constant against a varying gravitational load on the vehicle.

Title
Magnetic suspension systems for vehicles
Application Number
05/334,887
Publication Number
3899979
Application Date
February 22, 1973
Publication Date
August 19, 1975
Inventor
Godsey Jr Frank W
Agent
Waters Schwartz & Nissen
Assignee
Buryan Associates
IPC
B61b 13/08
B61B 13/08
B60L 13/04
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