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:
Sep. 27, 1994
Filed:
Jul. 29, 1992
Takayuki Kisi, Ibaragi, JP;
Keisuke Kasahara, Tokyo, JP;
Kabushiki Kaisha Naekawa Seisakusho, Tokyo, JP;
Abstract
A screw compressor has a male rotor and female rotor rotatably engaging each other in a casing. The male rotor has a radius R and Z-number of helical convex teeth, each of which is chamfered on a leading edge of an end facing the discharge end of casing to allow lubricating liquid to escape from a space between rotor teeth during discharge stages of operation. This prevents drastic increases in pressure upon the bearings due to a liquid compression phenomenon. Thrust forces produced by the liquid against a flat chamfer surface prevent scoring of the edges of the rotors and thus permit designs with narrow gaps between the rotors and the casing to improve the efficiency of the compressor.