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. 19, 1989
Filed:
Oct. 04, 1988
Neil A Newman, Omro, WI (US);
Herbert A Bankstahl, Fond du Lac, WI (US);
Brunswick Corporation, Skokie, IL (US);
Abstract
A marine propulsion system is provided with dual counterrotating propellers, and a shaft and gear arrangement for driving the propellers. In a preferred embodiment, the marine propulsion system includes a depending gearcase having a steerable lower portion which is pivotable about a steering axis relative to an upper gearcase portion. A pair of coaxial drive shafts extend longitudinally through the gearcase, and are interconnected with the engine output shaft so as to rotate in opposite directions in response to rotation of the output shaft. The counterrotating propellers are preferably mounted to a pair of coaxial propeller shafts, and appropriate gearing is disposed between the coaxial propeller shafts and the coaxial drive shafts to drive the propeller shafts, and thereby the propellers, in opposite rotational directions. In a preferred embodiment, the gearing includes counterrotating gears fixed to the counterrotating drive shaft so as to provide cancelling gear torque loads about the steering axis. The counterrotating propellers likewise provide cancelling propeller torque loads to further accommodate steering of the steerable gearcase portion.