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:
Jan. 07, 1997
Filed:
Oct. 10, 1995
Hideki Nakamura, Yonago, JP;
Keiji Yamasaki, Yasugi, JP;
Fujio Yamane, Yasugi, JP;
Toshiki Yoshida, Tochigi-ken, JP;
Tadashi Iizuka, Ashikaga, JP;
Akihiko Ishiyama, Tochigi-ken, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A compressor comprising a roller made of a cast iron which has a hardness of HRC 50 or more after heat treatment, and contains not less than 5 area % of graphite, and not less than 2 area % of crystallized eutectic structure including iron phosphide, and either a vane made of a material which has a hardness of HRC 70 or more after heat treatment and contains not less than 25 area % of undissolved carbides and nitride particles in total, the undissolved carbides including not less than 10 area % of MC type carbides, the nitride particles including at least one of TiN and NbN of not less than 5 area %, the undissolved carbides and the nitride particles having a mean grain size of not more than 5 .mu.m, or a vane made of a material including at least one of TiN and NbN particles of not less than 5 area %, the TiN and NbN particles having a mean grain size of not more than 5 .mu.m, the material essentially consisting of, by weight, 2.0 to 4.0 % of C, not more than 2.0 % of Si, not more than 1.5 % of Mn, 2.5 to 8.0 % of Cr, 20 to 40 % of W+2Mo, 3.0 to 15 % of V, not more than 15 % of Co, and the balance of Fe, the material having a hardness of HRC 65 or more after heat treatment.