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. 30, 1988
Filed:
Mar. 04, 1987
Applicant:
Inventors:
Kazuaki Shiinoki, Ebina, JP;
Koutarou Naya, Ebina, JP;
Shinji Mitsuhashi, Yokohama, JP;
Tadashi Hayakawa, Ebina, JP;
Riichi Uchida, Ibaraki, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F04C / ;
U.S. Cl.
CPC ...
417312 ; 417410 ; 418201 ;
Abstract
The present invention provides a screw vacuum pump unit in which both a screw block and a driving motor are mounted on one side surface of a casing of a speed change gear, both axes of a male rotor and a female rotor in the screw block are arranged in vertical adjacency within a substantially perpendicular virtual plane, and suction ports and discharge ports are arranged on both sides with the vertical plane intervening therebetween, whereby maintenance can be facilitated.