Outboard Marine Corporation

Bombardier Motor Corporation of America

Michael J Ewald

Daniel J Kreul

Philip James McGowan

Cy Gerard Werda

A propeller assembly that includes a plastic bushing that is secured, e.g., bonded, to an inner hub and is configured to engage an outer hub of a propeller. More specifically, and in an exemplary embodiment, the bushing includes a cylindrical shaped body having a bore therethrough, and a plurality of grooves are in an outer diameter surface of the cylindrical shaped body. The inner hub includes a cylindrical shaped body sized to extend into the bushing bore. A flange is at one end of the inner hub body, and at least one limp home tab extends from the flange. The propeller includes an outer hub having a cylindrical shaped body, and a plurality of blades extend from an outer diameter surface of the outer hub body. An inner diameter surface of the outer hub body has a plurality of protrusions that extend radially inward. Each protrusion is positioned to extend within a respective one of the grooves in the outer diameter surface of the bushing body. At least one limp home tab extends from the outer hub inner diameter surface.

Propeller hub

A propeller flare having a periodic shape and extending from the aft end of the propeller hub is described. The periodic shape of flare provides that the trailing edge, or aft end, of the propeller hub is increased only at locations where such increased material is needed to prevent exhaust gases from reaching the lower pressure region on the suction side of the blades. By only increasing the hub aft end at such selected locations, the efficiency and speed loss due to increased drag is minimized. In one embodiment, the flare is configured for a three blade propeller and includes three flare sections. Each flare section has a helical cross-sectional shape, and ramps are located intermediate adjacent flare sections. Each ramp is aligned with one of the propeller blades, and each ramp has a pitch at least about equal to the pitch of blades. Reliefs are located adjacent each ramp, and each relief extends from an aft end of the ring toward a fore end of the ring. Each ramp has a thrust surface, and the thrust surfaces align with each blade position and angle. The reliefs allow some bleed through of the exhaust gases, and the thrust surfaces provide thrust enhancement during engine operation. The ramps provide a local pressure increase and obstruct exhaust gases from entering into the propeller blades.

Growing community of inventors

Kenosha, WI, United States of America

Michael J Ewald