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:
Dec. 16, 1997
Filed:
Apr. 03, 1996
Takeshi Kawamura, Kanagawa-ken, JP;
Kiyoshi Yanagisawa, Kanagawa-ken, JP;
Shigeyoshi Nagata, Tokyo, JP;
Ebara Corporation, Tokyo, JP;
Abstract
The transverse tooth profile of a screw rotor which meshes with a companion screw rotor is defined by a tooth root circular arc, an outer circumferential circular arc, and two curves interconnecting the tooth root circular arc and the outer circumferential circular arc. One of the curves is defined by a trochoid curve generated by a point on an outer circumferential surface of the companion screw rotor. Alternatively, the curve may comprise two curve segments, and one of the two curve segments comprising a tooth tip arc which is defined as an arc having a radius of curvature equal to or smaller than the difference between a radius of curvature of the outer circumferential circular arc and a radius of a pitch circle of the tooth profile, and the other of the two curve segments comprising a curve connected to the tooth root circular arc and determined by a curve generated by the tooth tip arc of the companion screw rotor. The other curve is defined by determining a curve which defines an imaginary rack and thereafter producing a tooth profile curve generated by the imaginary rack.