Propeller for a marine vessel

Patent metadata

Field	Value
Publication number	US-12030604-B2
Application number	US-202017753154-A
Country	US
Kind code	B2
Filing date	Sep 18, 2020
Priority date	Sep 23, 2019
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

A propeller ( 20 ) for a marine vessel ( 10 ), the propeller ( 20 ) comprising a plurality of propeller blades ( 24, 26 ). The propeller blades comprise a leading edge ( 30 ), a trailing edge ( 32 ) and an outer edge ( 34 ) located between the leading edge and the trailing edge. A transition from the leading edge to the outer edge occurs at a first transition point ( 36 ) and a transition from the outer edge to the trailing edge occurs at a second transition point ( 38 ). A straight line from the first transition point to the second transition point coincides with the outer edge ( 34 ) or is located at least partially outside the propeller blade. A smallest distance (D 2 ) from the second transition point to the axis of rotation (A) is smaller than a smallest distance (D \ ) from the first transition point to the axis of rotation.

First claim

The invention claimed is:

1. A propeller combination comprising a forward propeller and an after propeller, said propellers being adapted to rotate in opposite directions around an axis of rotation, wherein each one of said forward propeller and said after propeller is a propeller according to the following:
a propeller for a marine vessel, said propeller comprising a plurality of propeller blades, said propeller being adapted to be rotated around said axis of rotation,
each one of said propeller blades comprising an edge that in turn comprises a leading edge, a trailing edge and an outer edge located between said leading edge and said trailing edge, as seen along said edge of said propeller blade,
wherein a transition from said leading edge to said outer edge occurs at a first transition point and a transition from said outer edge to said trailing edge occurs at a second transition point, wherein
as seen in a side plane view of said propeller blade in a plane that extends parallel to said axis of rotation, a straight line from said first transition point to said second transition point coincides with said outer edge or is located at least partially outside said propeller blade,
wherein a smallest distance from said second transition point to said axis of rotation is smaller than a smallest distance from said first transition point to said axis of rotation,
wherein, as seen in said side plane view of said propeller blade, a length of said outer edge along said axis of rotation is equal to or greater than 20% of the maximum length of the propeller blade along said axis of rotation,
where each of the transition points is arranged at ends of the outer edge where the extension of the outer edge does not coincide with the straight line and where the edge bends off towards said axis of rotation forming one of said leading edge or said trailing edge, when seen in said plane,
wherein said smallest distance from said first transition point to said axis of rotation for said after propeller is smaller than a smallest distance from said second transition point to said axis of rotation (A) for said forward propeller.

2. The propeller according to claim 1 , wherein said first transition point is the outermost point, as seen in a radial direction from said axis of rotation, of said propeller blade.

3. The propeller according to claim 1 , wherein the first and the second transition points are corners with a curvature radius smaller than 1/10 of a diameter of the propeller, or smaller than 1/50 of a diameter of the propeller.

4. The propeller according to claim 1 , wherein, as seen in said side plane view of said propeller blade, the length of said outer edge along said axis of rotation is equal to or less than 50% of the maximum length of the propeller blade along said axis of rotation.

5. The propeller according to claim 4 , wherein, as seen in said side plane view of said propeller blade, the length of said outer edge along said axis of rotation is equal to or less than 40% of the maximum length of the propeller blade along said axis of rotation.

6. The propeller according to claim 1 , wherein said smallest distance from said second transition point to said axis of rotation is equal to or less than 99% of said smallest distance from said first transition point to said axis of rotation.

7. The propeller according to claim 6 , wherein said smallest distance from said second transition point to said axis of rotation is equal to or less than 95% of said smallest distance from said first transition point to said axis of rotation.

8. The propeller according to claim 1 , wherein said smallest distance from said second transition point to said axis of rotation is equal to or greater than 70% of said smallest distance from said first transition point to said axis of rotation.

9. The propeller according to claim 8 , wherein said smallest distance from said second transition point to said axis of rotation is equal to or greater than 75% of said smallest distance from said first transition point to said axis of rotation.

10. A marine vessel comprising a propeller combination according to claim 1 .

Assignees

• Volvo Penta Corp

Inventors

• Jonsson Kåre
• Hallenstvedt Oddbjörn

Classifications

• B63H5/10 Primary

  of coaxial type, e.g. of counter-rotative type · CPC title

• B63H1/18

  with means for diminishing cavitation, e.g. supercavitation · CPC title

• B63H1/26 Primary

  Blades · CPC title