Power source apparatus including a plurality of output current amplifiers connected in parallel and MRI apparatus using the same

Patent 5721490 Issued on February 24, 1998. Estimated Expiration Date:

February 7, 2016. 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.

Abstract Claims Description Full Text

Patent References

5017871

Transformer-coupled gradient speed-up circuit
Patent #: 5063349
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Inventor: Takahashi

Inventors

Assignee

Hitachi Medical Corporation

Application

No. 597959 filed on 02/07/1996

US Classes:

324/322, Electronic circuit elements600/410Magnetic resonance imaging or spectroscopy

Examiners

Primary: Arana, Louis

Attorney, Agent or Firm

Antonelli, Terry, Stout & Kraus, LLP

Foreign Patent References

647015 JP. 06/13/1994

International Class

G01V 003/00

Foreign Application Priority Data

1995-02-09 JP

Abstract

A power source apparatus distributes a current command value to be supplied to a load to a plurality of output current amplifiers connected in parallel with the load, and each of the output current amplifiers supplies an output current corresponding to the current command value so distributed. This power source apparatus prevents a circulating current between the output current amplifiers by controlling each output current amplifier so that the difference between the output current from each output current amplifier and the distributed current command value becomes zero, or by inserting current limiting devices into the output line of each output current amplifier.