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:
Apr. 26, 2005
Filed:
Nov. 20, 2002
Takeshi Hida, Shimizu, JP;
Masayuki Urashin, Shimizu, JP;
Shigekazu Nozawa, Shimizu, JP;
Hiroki Ohsumimoto, Shimizu, JP;
Hirotaka Kameya, Tsuchiura, JP;
Atsushi Watanabe, Chiyoda, JP;
Takeshi Hida, Shimizu, JP;
Masayuki Urashin, Shimizu, JP;
Shigekazu Nozawa, Shimizu, JP;
Hiroki Ohsumimoto, Shimizu, JP;
Hirotaka Kameya, Tsuchiura, JP;
Atsushi Watanabe, Chiyoda, JP;
Hitachi, Ltd.,, Tokyo, JP;
Abstract
A screw compressor of which a female rotor is driven by a motor, and of which a male rotor is driven by the female rotor. The male or female rotor is composed of a member which is made of cast iron and is subjected to surface hardening treatment or heat treatment including quenching. The surface hardening treatment may include sulphonitriding or nitiriding treatment. In the case of subjecting the cast iron to the heat treatment, austemper treatment is applied.