Ships – Spars – Masts and masting
Reexamination Certificate
2003-08-08
2004-11-16
Swinehart, Ed (Department: 3617)
Ships
Spars
Masts and masting
C114S102100
Reexamination Certificate
active
06817308
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to sailing rigs and particularly to masts for sailing rigs.
2. Prior Art
Sailing rigs have existed for thousands of years. A typical sailing rig includes an essentially oval in cross-section fixed mast which is held in place by a plurality of stays, tumbuckles and shackles. The mast supports the sail and along with the boom creates driving force to cause a watercraft to be propelled across water. However, such a traditional mast for sailboats act as an obstacle to the airflow and are not aerodynamic. Accordingly, they result in high drag and the efficiency of the sailing rig is generally reduced.
To overcome these problems of the traditional mast, rotating wing masts or unarigs have been provided. Such rotating wing masts or unarigs are aerodynamic and improve the efficiency of the sailing rig. However, such rotating wing mast or unarigs are placed well forward in the sail powered craft and as a result prevent the utilization of a spinnaker.
While both the traditional and rotating wing mast have existed for a long time, both have one or more significant shortcomings. In particular, they have a high center of gravity which contributes to the instability and the tendency to turn over or pitch of the sailing craft in high winds, particularly monohulls. Still further, the utilization of a plurality of stays, tumbuckles and shackles provides a plurality of additional failure points in the sailing rig and thereby reduces the reliability. Additionally, such sails have one or more of the disadvantages as follows: a narrow fully powered range, have inadequate camber control of the sail and generally require the utilization of additional storm sail.
SUMMARY OF THE INVENTION
Accordingly, it is a general object of the present invention to overcome the disadvantages of the prior art.
In particular, it is an object of the present invention to provide a mast which is aerodynamic, low in drag, high in efficiency, a low center of gravity, a wide fully powered range, good camber control of the sail, high reliability and moderate leech.
Still further, it is the object of the present invention to provide a sailing rig with a mast which can be utilized together with a spinnaker and does not require a storm sail.
In keeping with the objects of the present invention, the present invention provides a sailing rig including a freestanding rotating aerofoil sectioned mast. The aerofoil sectioned mast is elliptically curved from the mast base to the masthead and is rotatable about an aft slanted axis which aligns the mast base and the masthead such that the masthead does not fall off to leeward when the mast rotates. Still further, the aerofoil sectioned mast is tapered in aerofoil section from the mast base to the masthead to reduce the weight of the aerofoil sectioned mast toward the masthead to thereby reduce the center of gravity. Moreover, the aerofoil sectioned mast is formed such that the thickness of the walls of the aerofoil section from the mast base to the masthead is reduced to achieve more flexibility and further reduce the weight at the masthead.
REFERENCES:
patent: 5176091 (1993-01-01), Burnham, II
patent: RE35081 (1995-11-01), Quigley
patent: 5603277 (1997-02-01), Webb
Koda & Androlia
Swinehart Ed
LandOfFree
Sailing rig with freestanding rotating aerofoil sectioned mast does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sailing rig with freestanding rotating aerofoil sectioned mast, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sailing rig with freestanding rotating aerofoil sectioned mast will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3293447