Weed-resistant outboard motor drive system
US6669516B1 · kind B1 · utility
Inventors
Key dates
| Filing date | Aug 20, 2002 |
| Grant date | Dec 30, 2003 |
| Priority date | — |
| Expiry date | Aug 20, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB63H2023/344
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A weed and impact resistant outboard motor drive system includes a motor and a small diameter metallic propeller. An elongated flexible shaft is coupled between the motor and propeller. The flexible shaft is encased within a curved tubular housing that is secured to the motor at one end and carries a propeller shaft at its other end. The drive system is clamped to the boat with the motor above the boat and the propeller axis parallel to the water surface. A tangent to the curved tubular housing, as it enters the water, forms an acute included angle with the water surface that is no greater than 55°. The small in-the-water profile of the drive system and the angle of entry of the tubular housing into the water minimize weed pickup. The high speed rotation of the small diameter propeller facilitates cutting and churning through of any weeds that are picked up, while enabling proper trolling speeds. The low inertia of the drive system and the metallic propeller help to withstand contacts with rocks and the like. A tapered skeg is mounted to the tubular housing adjacent to the small propeller, extends beyond the blade tips of the propeller and has an angle of taper that is no great…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.