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:
Sep. 29, 1998
Filed:
Apr. 20, 1995
Yoshinori Ojima, Fujisawa, JP;
Kozo Matake, Kawasaki, JP;
Genichi Sato, Chigasaki, JP;
Yasushi Hisabe, Samukawa-machi, JP;
Masami Nagayama, Fujisawa, JP;
Katsuaki Usui, Kawasaki, JP;
Hiroaki Ogamino, Kawasaki, JP;
Ebara Corporation, Tokyo, JP;
Abstract
A multishaft electric motor has a plurality of juxtaposed rotors having respective permanent magnets disposed therearound, and a plurality of sets of armature elements disposed fully circumferentially around the rotors, respectively, the permanent magnets of adjacent two of the rotors having a plurality of pairs of unlike magnetic poles for magnetically coupling the rotors through the armature elements between the permanent magnets. A positive-displacement vacuum pump includes a casing, a pair of pump rotors rotatably disposed in the casing in confronting relation to each other, and a two-shaft electric motor coupled to the pump rotors for rotating the pump rotors in opposite directions. The two-shaft electric motor may comprise a pair of juxtaposed rotors and a pair of sets of armature elements disposed fully circumferentially around the rotors, respectively.