Marine outdrive with surface piercing propeller and stabilizing shroud
OwnerHoward M. Arnesoninventor
Life of this patent
Estimating the term…
Abstract
An improved fin structure for attachment to the propeller shaft mount of a surface piercing marine outdrive apparatus. The fin structure has one fin member at one side of the mount for the propeller drive shaft of the marine outdrive. The fin member is so situated that it is in a position to destroy any side thrust exerted by the propeller on the water so as to avoid "walking" of the mount on the water and the propeller laterally.
Claims84
In a marine outdrive for a boat having a transom and tubular propeller shaft mount and a shaft received in the mount, the shaft having a forward end and a rear end, the combination with said mount of:
- a shroud;
- a propeller adapted to be secured to the rear end of the shaft for rotation relative to the mount;
- and
- a mount with the shroud at least partially surrounding the propeller when the propeller is mounted on the shaft and when the shaft is in the tubular propeller shaft mount, the shroud having an inner surface spaced outwardly from the rotational envelope of the ends of the propeller to form a channel with said inner surface, the shroud having a tangential portion substantially parallel to a tangent of said rotational envelope, said channel having an upstream end, a downstream end and an intermediate part, said channel progressively decreasing in width from said tangential portion of the shroud as said intermediate part of the channel is approached from said upstream end and said channel progressively increasing in width as the downstream end of the channel is approached from said intermediate part.
A boat comprising:
- a hull having a transom and a marine outdrive secured to and extending rearwardly from the transom, said marine outdrive including tubular propeller shaft mount and a shaft received in the mount and having a forward end and a rear end, and the shaft rotatably carried by the mount;
- a shroud;
- a propeller secured to the rear end of the shaft, said shaft being received in the mount for rotation relative to the mount;
- a mount with the shroud at least partially surrounding the propeller when the propeller is mounted on the shaft and when the shaft is in the tubular propeller shaft mount, the shroud having an inner surface spaced outwardly from the rotational envelope of the ends of the blades of the propeller to form a channel with said inner surface, the shroud having a tangential portion substantially parallel to a tangent of said rotational envelope, said channel having an upstream end, a downstream end and an intermediate part, said channel progressively decreasing in width from said tangential portion of the shroud as said intermediate part of the channel is approached from said upstream end and said channel progressively increasing in width as the downstream end of the channel is approached from said intermediate part;
- and
- means coupled to said boat for rotating the shaft.
In a marine outdrive for a boat having a transom and tubular propeller shaft mount, a propeller and a shaft, having a forward end and a rear end, said propeller adapted to be secured to the rear end of the shaft for rotation relative to the mount;
- and
- a shroud having a means for coupling the shroud to the mount with the shroud at least partially surrounding the propeller when the propeller is mounted on the shaft and when the shaft is in the tubular propeller shaft mount, the shroud having an inner surface spaced outwardly from the rotational envelope of the ends of the propeller to form a channel with said inner surface, the shroud having a tangential portion substantially parallel to a tangent of said rotational envelope, said channel having an upstream end, a downstream end and an intermediate part, said channel progressively decreasing in width from said tangential portion of the shroud as said intermediate part of the channel is approached from said upstream end and said channel progressively increasing in width as the downstream end of the channel is approached from said intermediate part.
Dependencies are inferred from the claim text.