Magnetic levitation apparatus and method
Patent 4910633 Issued on March 20, 1990. Estimated Expiration Date: 
September 7, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 7, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2377175 2566221 3215901 3512852 3664196 3721984 3791704 3815963 3860300 Variable permanent magnet suspension system InventorApplicationNo. 241482 filed on 09/07/1988US Classes:361/144, For lifting or holding310/90.5, Magnetic bearing361/147With permanent magnetExaminersPrimary: Pellinen, A. D.Assistant: Osborn, David Attorney, Agent or FirmInternational ClassF16C 039/06AbstractA method and apparatus for levitating objects in a magnetic field, comprising disposing at least one electromagnet having a centrally disposed core with at least one end positioned adjacent an outer surface of the electromagnet, connecting the electromagnet to a switchable electrical power source, and mounting at least one magnet on the object to be levitated. At least one magnetic field sensor is disposed adjacent the core end for providing an output signal indicative of a magnetic field level and orientation. A reference source is used for generating a variable reference signal which is applied to one input of a comparison element which is in turn connected to the sensor at a second input. The comparison element is used for comparing the respective voltages generated by each source, sensor and reference, and for providing an output signal indicative of a relative status of the two. The output signal is applied to a field strength controller connected to the comparison element and in series with the power source for adjusting electrical power delivered to the electromagnet in response to changes in the comparison output signal.Field of SearchCONTROL CIRCUITS FOR ELECTROMAGNETIC DEVICESSystems for magnetizing, demagnetizing, or controlling the magnetic field For lifting or holding Systems for magnetic field stabilization or compensation With permanent magnet Including means for using, or compensating for, the induced EMF of the electromagnetic device Magnetic bearing ELECTROMAGNET OR HIGHLY INDUCTIVE SYSTEMS By magnetic field MAGNETICALLY SUSPENDED CAR By permanent magnets only Including means to sense or control car position or attitude with respect to guideway MAGNETIC Calibration Permanent magnet testing Magnetometers Fixed coil magnetometer Movable magnet or magnetic member interacts with magnetic field | |
