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:
Aug. 28, 1990
Filed:
Mar. 30, 1989
Applicant:
Inventor:
Toshiaki Nagai, Shimizu, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04C / ;
U.S. Cl.
CPC ...
418194 ; 4182013 ;
Abstract
A nonlubricated screw fluid machine comprising a pair of rotors including male and female screw rotors provided with a dual lead tooth profile on the basis of the difference in the temperature between the outlet side and the inlet side when forming tapered rotors considering the temperature distribution within the rotors in which each of the shape of the male and female rotors after the thermal expansion is employed as a basic tooth profile.