The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 2005
Filed:
Dec. 12, 2002
Tsuyoshi Wakuda, Hitachi, JP;
Michiya Okada, Mito, JP;
Shigeru Kakugawa, Hitachi, JP;
Hiroyuki Watanabe, Hitachi, JP;
Tsuyoshi Wakuda, Hitachi, JP;
Michiya Okada, Mito, JP;
Shigeru Kakugawa, Hitachi, JP;
Hiroyuki Watanabe, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A magnet for MRI apparatus has a magnetic circuit which includes a magnetic flux path formed by a ferromagnetic material and a magnetic flux path formed by magnetic flux return coils or magnetic flux control coils, so that a 5-gauss line of leakage fluxes can be kept within a sphere 3 m in radius even when the static magnetic field intensity exceeds 1 tesla and a comparatively light magnet for MRI apparatus can be provided. Further, the fluxes escaping vertically from the static magnetic field sources are led compactly to a horizontal direction by installing magnetic flux paths of ferromagnetic materials and coils with polarities opposing those of the static magnetic fields. This arrangement minimizes an increase in the total height of the magnet for MRI apparatus, keeping the magnet within the total height of 3 m.