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:
Dec. 27, 1994
Filed:
Oct. 02, 1992
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In a magnetic bearing carrying a rotary shaft in the air, the rotary shaft is required to rotate substantially at the same position. In controlling the position of the rotary shaft, a first exciting current I.sub.f is supplied to a plurality of first electric magnets formed in the proximity of one end of the rotary shaft, whereas a second exciting current I.sub.r is supplied to a plurality of second electric magnets formed in the proximity of the other end of the rotary shaft. The first exciting current I.sub.f is represented by the sum of a first biasing current I.sub.f, a first control current i.sub.Hf for translation, and a first control current i.sub.Kf for rotary motion. The second exciting current I.sub.r is represented by the sum of a second biasing current I.sub.r, a second control current i.sub.Hr for translation, and a second control current i.sub.Kr for rotary motion. Under such conditions, a ratio I.sub.f /I.sub.r between the first and second biasing currents, a ratio i.sub.Hf /i.sub.Hr between the first and second control currents for the translation, and a ratio i.sub.Kf /i.sub.Kr between the first and second control currents for the rotary motion are appropriately determined so as not to cause a mutual interference between the translation and the rotary motion of the rotary shaft.