IP Library › Granted Patent US 12,448,098
Granted Patent B2
US 12,448,098 · App. 18/739,753 · Granted Oct 21, 2025

Propeller

Inventor: Gregory Charles Sharrow (Grosse Pointe Park, MI)
Assignee: Sharrow Engineering LLC
B63H1/265B64C11/00B64C11/005B64C11/16B64C11/18B64C11/20F01D5/141F03D1/06F03D1/0625F04D29/384F04D17/025F04D29/281F05B2210/16F05B2250/24F05B2250/25F05B2250/26
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Quick Facts
Patent No.
US 12,448,098
App. No.
18/739,753
Granted
Oct 21, 2025
Kind
B2
Abstract

A propeller having a plurality of blades extending radially outward from a hub, the blades forming a loop. Each loop can have an intake portion, an exhaust portion and a tip portion extending radially outward from the hub and a gap between the intake root and the exhaust root.

Claims (16)

1. A propeller comprising:

a plurality of blades, each of the plurality of blades having an intake portion, an exhaust portion, and a tip portion extending from the intake portion to the exhaust portion;

a hub;

the plurality of blades, each blade forming a loop-extending outward from the hub and disposed around the hub, each blade connected with the hub via a root of the intake portion and a root of the exhaust portion, wherein the root of the exhaust portion is forward of the root of the intake portion when extending outward from the hub;

each blade comprising a plurality of parameter sections having selected one or more of the parameters including skew angle, roll angle, rake, radius, pitch angle, and vertical angle values;

a parameter section of the plurality of parameter sections at the transition from the intake portion to the tip portion defined by parameters to cause the amount of non-axial lift in the tip portion to be greater than the axial lift in the tip portion; and

a parameter section of the plurality of parameter sections or an area between consecutive parameter sections of the plurality of parameter sections in the tip portion having a roll value of 90 degrees.

2. The propeller of claim 1 comprising the plurality of blades each having an irregular helical median line.

3. The propeller of claim 1 wherein the plurality of blades are configured so non-axial lift in the intake portion is less than non-axial lift in tip portion.

4. The propeller of claim 1 wherein the plurality of blades are configured so the amount of non-axial lift in the exhaust portion is less than the non-axial lift in the tip portion.

5. The propeller of claim 1 wherein the tip portion has a 90 degree roll angle closer to the exhaust portion than to the intake portion.

6. The propeller of claim 1 , wherein the plurality of parameter sections include the root of the exhaust portion forward of the root of the intake portion when extending outward from the hub, and skew continually decreases.

7. The propeller of claim 1 , wherein the plurality of parameter sections are aligned along a non-helical median line.

8. The propeller of claim 1 , wherein one or more selected parameters for one or more of the plurality of parameter sections are defined to cause the amount of non-axial lift in the intake portion to be less than the non-axial lift in tip portion.

9. The propeller of claim 1 , wherein one or more selected parameters for one or more of the plurality of parameter sections are defined to cause the amount of non-axial lift in the exhaust portion to be less than the non-axial lift in the tip portion.

10. The propeller of claim 1 , wherein the plurality of parameter sections are planar.

Assignments (4)
SECURITY INTEREST Recorded Oct 15, 2025
From: SHARROW ENGINEERING INC.
To: BLADES AND WAVES, LLC
Reel/Frame 072575/0470 →
ENTITY CONVERSION Recorded Oct 15, 2025
From: SHARROW ENGINEERING, LLC
To: SHARROW ENGINEERING INC.
Reel/Frame 073078/0744 →
SECURITY INTEREST Recorded Mar 10, 2025
From: SHARROW ENGINEERING, LLC
To: BLADES AND WAVES, LLC
Reel/Frame 070455/0825 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 11, 2024
From: SHARROW, GREGORY CHARLES
To: SHARROW ENGINEERING LLC
Reel/Frame 067692/0456 →
Continuity (7)
Continuation 18194994 · Apr 3, 2023
Continuation 17577587 · Jan 18, 2022
Continuation 15897767 · Feb 15, 2018
Continuation 15605764 · May 25, 2017
Provisional Application 62508139 · May 18, 2017
Provisional Application 62342284 · May 27, 2016
Related Publication 20240336341A1 · Oct 10, 2024
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