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:
Jun. 09, 1992
Filed:
Oct. 19, 1990
Takeshi Toyoshima, Ibaraki, JP;
Mitsuo Ogura, Katsuta, JP;
Hitachi Koki Company Limited, Tokyo, JP;
Abstract
A molecular drag pump for delivering a gas under molecular flow conditions comprises a pair of parallel, helically threaded rotors rotatably mounted in a stationary housing. The rotors have respective helical threads and respective helical grooves, and are held in close mesh with each other. The helical threads are helically inclined in one direction to the axes of the rotors, and have a flank angle such that the helical threads are closely received in the respective helical grooves while keeping the threads out of contact with each other. The rotors are rotated in one direction about their respective axes to move a gas introduced through an inlet port toward an exhaust port axially along the rotors.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile