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. 08, 1981
Filed:
Jun. 28, 1979
Theodore J Holtermann, Milwaukee, WI (US);
Outboard Marine Corporation, Waukegan, IL (US);
Abstract
The marine propulsion device includes a lower unit normally submerged in water, a propeller carried by the lower unit, and an annular shroud surrounding the propeller blades and defining a passageway through which water flows. The shroud, which can be in the form of a Kort-type nozzle for augmenting propeller thrust, has a trailing edge located rearwardly of the travel path of the propeller blade tips. The trailing edge of the shroud includes an annular recess through which either engine exhaust gases or atmospheric air is delivered to ventilate the low pressure area created behind the trailing edge of the shroud during forward movement of the lower unit through water.