Texture gearcase for a marine propulsion system
US5967866A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1997 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Dec 2, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B61/045
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A lower unit for a marine propulsion system has a flow disrupter positioned along the side wall of the vertical strut above the torpedo gearcase. The strut has a high pressure side and low pressure side which results from the strut being positioned at an angle with respect to the direction of boat travel in order to compensate for steering torque. The flow disrupter is positioned on the low pressure side of the strut, and promotes the separation of water passing over the vertical strut in a controlled manner, thereby reducing steering jerks during acceleration due to dramatic hydrodynamic flow changes. The flow disrupter consists of a series of steps or textured areas positioned along the aft section of the vertical strut. In a preferred embodiment, each of the steps contains a vent passage permitting exhaust to exit the strut through the steps to further promote controlled separation of water passing over the strut.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.