The present invention relates to a sailing yacht.
The research of speed has been from the beginning a distinctive feature of the development of marine engineering, not only because beneficial for the purpose of transporting goods or in war, but also because the chance to escape the bad weather is a safety factor, so interesting also for yachting in its various manifestations, from racing to cruising.
The modern sailing boats, like motor boats, are no longer bound to the limit of their critical speed linked to the length of the hull, but, being able to glide reach a speed-time characteristics of the most fast motorboats.
The ability to glide for a given sail area, and a given righting moment capable of counteracting the heeling of the sail plan under the thrust of the wind, appear to be directly proportional to the boat's lightness, and the possibility of having a lifting and lift effect (lift) by immersed airfoils (as hydrofoils).
For this reason the multihulls are at an advantage because they are able to generate high righting moments by virtue of their shape, while the monohulls are forced to turn to a drift ballasted. The greater impetus to the increase in speed of monohulls in recent times, as well as constant development linked to new available composite materials, is due to the appearance of tilting tendencies that have led to a higher righting moment by moving upwind a reduced weight ballast than what it would be in a keel fixed configuration of equal draft.
Recently it has been added the use of fixed or retractable profiles, known with the term of foils that are used to generate a lift generating a righting moment for example leaking to the leeward side of the hull below the water surface, as also described and illustrated in U.S. Pat. No. 7,644,672, always in order to reduce the weight of ballast required to equal conditions.
From U.S. Pat. No. 4,044,703 it is known a boat which then provides two ballasted drifts revolving around a same longitudinal axis place in the boat median plane: in this case the maximum righting moment can be at most equal to that generated in the case of a mono derives tilting.
In the patent document IT1234024 fast monohull trend is taken into consideration which tend to rely more and more to the stability of shape to decrease the weight where it is proposed an advantageous use of two ballasted overhead drifts arranged at the sides of the hull, with not only functions to move the windward ballast but also to dispose the axes of rotation according to appropriate angles so as to generate lift in different gaits, so as to use the same drifts to reduce the weight of ballast replacing it with the righting moment generated by the reactions.
From a comparison between the dual vessel solution derives tilting referred to above and that of a hull equipped with single canting keel, such as that described in U.S. Pat. No. 5,163,377, it can detect the following points in favor of either solution:
The object of the invention in question is to provide a sailing yachtable to improve and optimize the solutions of the known art specified above.
In particular, an object of the present invention is to provide a sailing yacht provided with equal righting moment and equal draft obtained with the use of a lower weight ballast, as well as with the eventual possibility of modifying the angle of incidence of the wing profile of the drift blades. This is by virtue of their angular position with respect to the main rotation axis (also not parallel to the axis of symmetry of the hull), both by virtue of the rotation of the same with respect to the rotation axes, so as to generate hydrodynamic forces with the triple function: both lifting, both of increased righting moment, both antiscarroccio.
The structural and functional characteristics of the present invention and its advantages will become even more clear and evident from the underlying claims, and in particular from an examination of the description that follows, referring to the attached figures, which show a preferred but not restrictive form of realization boat sailing in question, in which:
With specific reference to the enclosed
The position of the axis Y of rotation is placed in correspondence of the surface of hull S, and above it the structure continues to generate a lever arm adapted to rotate the whole drift 1,1′ by means of hydraulic actuators A and A′ or alternatively from cables operated by winches (not shown), or with other suitable handling, which act on the end of the drift 1,1′ above the fulcrum point that is contained within the same hull S, i.e. with direct handling on fulcrum of the axis Y,Y′. In the extreme position in which the drifts 1,1′ are brought to the center of the yacht I (
As shown more clearly in
In detail, each mechanism M,M′ of ratchet AR comprises a hydraulic cylinder 2 mounted on a relative drift 1,1′, and provided with a respective rod 3 with a groove 4 on which a safety restraint 5 is mounted to axis 11 and via the interposition of a return spring 6.
Each mechanism M, M′ also comprises a hydraulic cylinder 7 defining a release for said mechanism M, M′ provided with conical end 10, a conical bushing 8 arranged below for the centering and the engagement of the mechanism M,M′, and a conical bushing 12 arranged above for centering and coupling said mechanism M, M′, and an end portion 9 of the elastic stem 3.
In essence, in the yacht I of
A. operating position with both weights attached to drift 1′;
B. operative position of transfer of ballast Z from drift 1′ to drift 1;
C. operating position corresponding to a navigation in light winds with Z′ on 1′ windward and Z on 1 leeward;
D. operative position corresponding to a navigation with downwind with Z′ on 1′ and Z on 1, in which both of the airfoils of the drift blades 1 and 1′ rotated with a positive angle of incidence generate upward lifting. This position can also be given in case of need to reduce the draft;
E. operating position for the transfer of both the ballast Z and Z′ from 1′ to 1;
F. operative position with both ballets Z and Z′ hooked to drift 1 on opposite side with respect of position A.
in
Therefore, the advantageous use of the double structured drifting so derived is evident both in dynamic and static terms, as compared to the displacement of the hull center line due to the rotation of the drift 1,1′.
Another advantage lies in the possibility of bringing out the full drift blade 1,1′ from the water surface with the entire ballast Z+Z′, immersed in the water leaving the only profile downwind, without ballast (
Such increasing of righting moment is obtained therefore by rotating the drift blade 1 or 1′ towards the outside of the water line, thus increasing the incidence of the wing profile and generating greater lift, or by rotating one or both of the blades drift 1,1′ around its own axis R and R′ thus generating a windward positive and downwind negative lift effect, consequently increasing the righting moment, or both positive lift effect consequently increasing the possibility of glide.
Number | Date | Country | Kind |
---|---|---|---|
15202319.8 | Dec 2015 | EP | regional |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/IB2016/057831 | 12/20/2016 | WO | 00 |