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:
Oct. 29, 2002
Filed:
Apr. 09, 2001
Hitoshi Nishimura, Shimizu, JP;
Akira Suzuki, Shimizu, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An oil free screw compressor includes a compressor main body directly connected to a high speed motor via a drive side gear and a driven side gear having a uniform speed ratio. A bearing in a side of the high speed motor employs one having the same size as that of a bearing in a side of the compressor main body. The same material as a viscous seal provided at both end portions of a male rotor and a female rotor is used for a viscous seal provided at both end portions of a motor shaft. The high speed motor is driven by a high frequency type inverter. The electric motor side and the compressor main body side are made in a rotational shaft structure which is dummy symmetrical about a uniform gear portion.