Sailboat with sail-mast tilting according to navigation conditions

Abstract

 A sailboat having features of adaptiveness to the navigation conditions, wherein the mast supporting the sails is associated to an extension thereof supporting a keel structure and a ballast and is rotatable on an axis coincident with the bow-stern axis so that the mast of the boat can tilt owing to the force of wind, said tilting being resisted by the weight of the ballast; the arrangement being such that within the maximum allowed amount of tilting of the mast, the hull of the boat remains substantially horizontal.
The arrangement according to the invention may also be used on boats having a plurality of hulls.
According to the invention, the bow-stern axis along which said mast is hinged is coincident with the anchor points of the stays.
In register with the hinge point of the mast oleodynamic dampers may be provided for improving the stability of the boat.

Description

[0001] The present invention relates to a sailboat with sail-mast tilting according to navigation conditions.

[0002] More in particular the present invention refers to a sailboat provided with supporting means for an integral unit constituted of mast, ballast and keel structure, capable of rotating on the bow-stern axis of the boat in response to variable conditions both of wind and/or navigation in order to maintain substantially unchanged the longitudinal attitude of the boat, i.e. in order to maintain substantially horizontal the same.

[0003] It is well known that sailboats are subject to inclination downwind owing to the athwart fore component of the wind since the horizontal capsizing force-­component caused by the wind can be only partially compensated by the ballast located under the hull of this kind of boat. All this entails a number of inconveniences; inclination of the hull, need for a firm fastening down of movable objects present on board, need for particular apparatus on board capable of withstanding inclination without inconveniences (kitchens, beds, etc.), danger of overturning the boat (capsizing), well known to anyone expert in navigation under sail.

[0004] According to the present invention, a sailboat of the abovementioned kind is provided, wherein the mast is associated to an extension thereof supporting both ballast and keel structure and is rotatably mounted on an axis coincident with the bow-stern axis, and passes through the hull of the boat through a mast step realized in the hull itself, so that the mast of the boat may be tilted owing to the action of the wind, resistance being made against such tilting by the weight of the ballast arranged to obtain a tilting opposed to that of the mast, the arrangement being such whereby within the maximum range of tilting of said mast, the hull of the boat remains substantially horizontal whatever tilt said mast assumes.

[0005] Again according to the present invention, the conventional underwater keel is solid with the ballast, mounted on an extension of said mast.

[0006] Again according to the present invention, the bow-­stern axis on which said mast and its extension bearing keel and ballast are rotatably mounted, coincides with the points at which the stays supporting the mast are fixed, so that said stays remain taught whatever the angle of tilt of the mast.

[0007] Once more according to the present invention, the mast may be provided with shrouds arranged in the shape of a diamond and kept in place by means of a conventional crosstree.

[0008] The present invention will now be disclosed with reference to a preferred embodiment thereof, given by way of a non-limitative example and with reference to the figures of the attached drawings, wherein:

figure 1 shows a longitudinal sectional view of the sailboat according to the present invention taken at its waist;

figure 2 shows a transversal sectional view of the boat of figure 1, taken on plane II-II; and

figure 3 shows a top plan view of the boat according to the invention with the mast shown trimmed towards port.

[0009] With reference to the drawings, and in particular to figure 1, in 10 a boat is shown sailing over a water surface 11. Substantially halfway along its length (with respect to the center of gravity), the boat 10 is provided with a mast 12 rotatably mounted on bearings 13, 14 by means of a pin 15.

[0010] The mast 12 and its extension 16 supporting a keel structure 17 and a ballast 18 may rock along the axis 19-­20 passing through the hull of the boat 10 provided with a step 21.

[0011] At the bow and stern of the boat 10 connections 22, 23 may be provided, aligned with the axis 19-20 for eventual stays 24, 25 arranged so that the plane defined by the mast 12 and by the stays 24, 25 may freely rotate along the axis 19-20 without introducing undue slacks or tensions.

[0012] The structure according to figure 1 may also be appreciated from figure 2 wherein reference numerals as used in figure 1 indicate corresponding parts.

[0013] In figure 2 can be seen the tilt α assumed by the mast 12 under the action of the wind component Fv with respect to the hull of the boat 10, said tilting α being opposed by the weight P of the ballast 18.

[0014] The amount of the tilting of the mast 12 is a function of the proportioning of the distances of the pressure centers of the sails on the mast 12 and of the length of the extension 16 of the mast 12 supporting the ballast 18 and, obviously, of the weight of the ballast 18.

[0015] The pin or shaft 15 rotatable in the bearings 13, 14 may be associated to locking means for preventing its tilting with respect to the hull when it is desired, for instance for the sporting pleasure of sailing a boat with a conventional behaviour using a trapeze to increase the balancing torque.

[0016] The calculations relating to the dimensioning of the mast 12, the length of its extension 16, the weight of the ballast 18 may be effected according to the well-­known rules of composition of the forces in play and a detailed description thereof is not deemed necessary.

[0017] According to a modification of the present invention, not shown in detail, the pin or shaft 15 along which the mast 12 and its extension 16 may tilt, can be coupled to hydrodynamic dampers or the like (not shown), for improving the stability of the boat.

[0018] According to a further modification, there may be provided in addition to said hydrodynamic dampers or the like, elastic members for providing a progressive character to the automatic action of adjustment to the wind conditions obtained with the arrangement according to the present invention.

[0019] The arrangement according to the present invention, as it will be clear to a person skilled in the art, is not limited to a single-masted structure, but may also be adopted in boats having a plurality of masts.

[0020] Further, the present invention has been disclosed with reference to a single-hulled boat. There is nothing to prevent use of the arrangement according to the invention in connnection with catamarans or the like.

[0021] The present invention has been disclosed with reference to preferred embodiments of the same, but it will be understood that in practice changes and modifications may by introduced by a person skilled in the art without departing from the scope of protection of the present industrial privilege.

Claims

1. A sailboat with mast-tilt adaptable to navigation conditions, characterized in that it comprises at least one mast supporting sails associated to an extension thereof supporting both a keel structure and a ballast, said mast being rotatably mounted on a shaft coincident with the bow-stern axis of said boat; the arrangement being such whereby said at least one mast supporting the sails may tilt in compliance with the action of the wind, opposed in this tilting by the weight of said ballast arranged to tilt in a direction opposed to that of said at least one mast, so that the hull of said boat remains substantially horizontal whatever the tilt of said mast supporting the sails may be.

2. A sailboat according to claim 1, characterized in that said mast and said support for the ballast pass through a step realized in the hull of said boat.

3. A boat according to claim 1 or 2, characterized in that the immersed keel structure is integral with the ballast mounted on the extension of said mast supporting the sails.

4. A sailboat according to one or more of the preceding claims, characterized in that the bow-stern axis whereon said mast and its extension supporting the keel structure and ballast is hinged is coincident with the anchor point of the stays holding said mast.

5. A sailboat according to one or more of the preceding claims, characterized in that the shaft whereon said mast and its extension are rotatably mounted is operatively associated to hydrodynamic dampers for improving the stability of the boat.

6. A sailboat according to one or more of the preceding claims, characterized in that in addition to said hydrodynamic dampers, elastic means are associated for providing a progressive character to the tilting motion of said mast and its extension.

7. A sailboat according to one or more of the preceding claims, characterized in that said hull is of the catamaran type.

8. A sailboat according to one or more of the preceding claims, characterized in that it comprises a plurality of masts.

9. A sailboat according to one or more of the preceding claims, characterized in that it comprises means for locking said mast or masts in an upright conventional position without possibility of tilting.

10. A sailboat with sail-mast capable of tilting according to the navigation conditions according to one or more of the preceding claims and substantially as shown and disclosed with reference to the figures of the attached drawings.

Drawing