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. 26, 1995
Filed:
Oct. 21, 1994
Teruo Maruyama, Hirakata, JP;
Akira Takara, Higashiosaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A vacuum pump includes a plurality of rotors accommodated in a housing, a plurality of bearings for supporting the shafts of the rotors, respectively, a fluid-suction opening and a fluid-discharge opening formed in the housing, and a motor for driving at least one of the rotors. The pump has a first pump structure section for suction and discharge of gas, the pressure of which is in a viscous flow region, by utilizing change in volume of a space formed by the rotors and the housing. A second pump structure section is provided for transporting gas, a pressure of which is in an intermediate flow region, and gas, the pressure of which is lower than a pressure of the intermediate flow region, by utilizing movement of the space from a suction side to a discharge side of the second pump structure section.