| JP2015120448 | ANTIMOTION DEVICE AND SHIP |
| WO/1996/033091 | WATER JET POWERED WATERCRAFT |
| US5636585A | 1997-06-10 | |||
| US4441445A | 1984-04-10 |
| CLAIMS 1. A monohull sailing vessel equipped by: a) a hull with a longitudinal dimension, a stern, a bow, a port and starboard side; b) at least one mast to hoist at least one sail; c) two side floats connected to the hull by two or more arms hinged longitudinally to it (fig.3); d) wherein the arms have preferably the length between the 50% and 60% of the beam of the vessel (fig.3a); e) wherein volumes of the side floats must be, each one, between 5% and 20% of the volume of the hull shape (fig.3b); f) wherein the leeward side floats in case of gusts give a sufficient righting moment to contrast the heeling moment due to the wind on sails (fig.4); g) wherein the volume of the upwind side float is filled with water to improve the righting moment of the vessel (fig.12); h) wherein the leeward side float, in normal sailing condition, is empty and positioned out of the water to limit the wetted surface of the vessel when sailing (fig.12) i) wherein, in mooring condition, the side floats are rotated toward the centre of the vessel, to limit the beam max of the vessel (fig.15) ; 2. The monohull of sailing vessel of claim 1 , wherein the arms on port side are free to rotate independently to the arms of starboard side, and vice versa (fig.5). 3. The monohull of sailing vessel of claim 1 , wherein the arms are rotated by hydraulic cylinder positioned inside the hull (fig.6). 4. The monohull of sailing vessel of claim 1 , wherein the arms are rotated by electric or electric/hydraulic motors positioned inside the hull (fig.8) 5. The monohull of sailing vessel of claim 1 , wherein the arms are rotated by electric or electric/hydraulic motors positioned at the hull bottom (fig.9) 6. The monohull of sailing vessel of claim 1 , wherein the arms are rotated by halyards drived by electric or electric/hydraulic winches on deck (f ig .10) 7. The monohull of sailing vessel of claim 1 , wherein the arms are rotated by halyards drived by electric or electric/hydraulic winches positioned on mast (fig.1 1 ) 8. The monohull of sailing vessel of claim 1 , wherein the side floats are filled with water by an electric or engine drived pump (fig.12) 9. The monohull of sailing vessel of claim 1 , wherein the side floats are filled with water by pumps directly positioned inside the side floats (fig.13) 10. The monohull of sailing vessel of claim 11 , wherein the side floats are equipped by discharge valves (fig.13) 11. The monohull of sailing vessel of claim 1 , wherein the side floats, in mooring condition, are lifted up to limit the draft of the vessel (fig.16) 12. The monohull of sailing vessel of claim 1 , wherein the side floats are equipped by an airbag system to unsik the vessel in case of leak (fig. 7) 13. The monohull of sailing vessel of claim 12, wherein the side floats are equipped by an airbag system that, if activated to the leeward side, rights the vessel from the capsized position (fig 18) 14. The monohull of sailing vessel of claim 1 , wherein the side floats are equipped by lifting hydrofoils (H) , that improve the vessel performance especially downwind, when the two side floats are in horizontal position (fig.14) |
VESSELS
TECNICAL FIELDS OF THE INVENTION
The present invention is related to mobile ballast for mono-hull sailing vessels, to optimize performance during sailing, and to reduce wetted surface and draft
BACKGROUND OF THE INVENTION
Actually the principle of stability for traditional mono-hull sailing vessels is based upon the ballast, fixed at the keel of the vessel, in order to obtain a sufficient righting moment to balance the heeling moment created by wind on sails (see fig.1 ). But this system has some disadvantages:
1 ) to obtain better performance, the stainless steel fins are always deeper and this particular geometry results limited in realization and scantling
2) since the ballast is invariable, sailing in light wind conditions, the ballast percentage respect the weight of the vessel, remains permanent, which means extra weight on board creating a penalty in performance
3) in case of a deep fin, and consequently a high draft, the vessel has serious problems in harbors
4) high risk of damage to the hull and appendages in shallow water
Also the Canting Keel system, the latest improvement, consists in the rotation of the fin and bulb to upwind, however has, some limitations and disadvantages (see fig. 2):
1 a) an angle limitation of the canting keel, at approximately 40 degrees, otherwise the fin would touch the hull
2a) in very light wind conditions it has the same problem of normal ballast vessels: too much weight of ballast
3a) in anchorage condition it always has a high draft OBJECT OF INVENTION
The of this invention is to improve the stability and performance of mono-hull sailing vessels. Furthermore, it can be equipped by an additional system to obtain an unsinkable vessel, and less draft. DESCRIPTION OF INVENTION
This invention is based upon the simple concept of using water as ballast with the advantage of pumping it upwind, as for the common water ballast. To improve this aspect , the hull has two side floats, port and starboard, and those have two arms, hinged in proximity of the sheer line of the hull (Z), permitting a free rotation(see fig.3) . The upwind side float works as water ballast (Y), while the leeward side float (X), that is empty and rotated in way to be out of water, works as extra floating volume only in case of gust (W), and stormy weather (see fig.4). So the leeward side float will touch the water and sink to give the extra righting moment if necessary. l The arms need to have a shape similar to the common trimaran and catamaran, this particular shape has the scope of avoid additional resistance duet to extra wetted surface (see fig...)
For vessels with length over 45750' it is preferable to connect the side floats to the hull with two arms for each side.
The centre of volume of the two side floats, needs to be positioned close to the longitudinal position of the hull of the vessel, to avoid modifying the longitudinal trim of the vessel, in static and dynamic condition.
Preferably the length of the arms must be between the 50% and 60% of the beam of the vessel.
The volumes of the side floats must be, each one, between 5% and 20% of the volume of the hull shape. This means that the volumes of the side float leeward, that is empty, gives at least the same maximum righting moment as for traditional vessels, having the same sail area, between 40 and 50 degree.
The hull and deck need to have, in proximity of the arms hinges, an end of stroke to block the rotation of the arms in case of high heeling angle.
The rotation could be commanded by a hydraulic system (cylinders), electric motors, or by halyards dedicated.
This invention matches perfectly with the ultimate mono-hull racing vessels, more specifically those racing for long regatta; for example, the Class 40 and Volvo Ocean Race.
This is because this type of vessels are very light, with hull shape that has further planning attitude. In fact to take the maximum advantage of the present invention the vessel must be as light as possible and with a flat hull shape, and a beam max that is between the 30% and 40 % of the hull
The reason for this huge beam, is to increase the transversal position of the side floats, in order to obtain a major righting moment (see fig.5)
Respect to a traditional ballast sailing vessel, the vessel formed in accordance with the present invention, with the same sailing area, has a superior righting moment an less heel angle, which optimizes the performance and comfort.
This invention, definitely offers a new era of performance, safety, and unsinkable capacity for all mono-hull sailing vessel. DETAILED DESCRIPTION OF THE EMBODIMENT
The following description has the scope of illustrating the preferred embodiment of this invention.
The first principle concept is the way of how to hinge the arms, and how to apply the rotation to the side floats.
This can be done in many ways, however, the preferred system is to hinge the arms of the side floats in an external position of the sheer line (beam max) to obtain about 100/120 degree of rotation.
The hinge (Z) is preferably stainless steel, and bolted to the hull, and must be accessible for check/maintenance and in case substitute (see fig.5)
The rotation, can be actuated in many ways:
1 by a hydraulic cylinder, that pushes and pull the arms from below and is partially outside of the of the topside of hull (see fig.6)
2 by a hydraulic cylinder, that pushes and pull the end of the arms of side floats. In this case the arms are longer respect the instance N.1 (see fig.7)
3 by an electric motor directly coupled, by a chain or belt, to the hinge of the arms of the side floats (see fig.8)
4 by an electric/hydraulic motor directly coupled to the hinge of the arms of the side floats (see fig.8)
5 by two electric or hydraulic motors positioned near the bottom of hull connected to the arms of the side floats by rods (see fig.9)
6 alternately by halyards dedicated that exit in proximity of the first couple of spreaders that are not swept back. The halyards can be two for each side floats, obtaining the rotation with the use of only one winch for each side floats. In this case the mast will have an extra load, and this load must be calculated to obtain the right scantling of the size of mast, (see fig.10)
7 this is the same principle of the instance N.6, but instead of using two winches on deck, the halyards, for the rotation of the side floats, can be commanded by two electric or hydraulic motor positioned in proximity of the first couple of spreaders. Off course, in this case, there is more comfort but is less performing because there is extra weight upward, causing a higher VCG, due to the two motors fixed at the mast (see fig.1 1 )
The system to embark water in the upwind side float is the following:
1 the water is embarked on board of the vessel, and the water is pumped in the upwind side float by a pump (see fig.12)
2 the side floats are equipped with a pump, which embarks the water directly in the upwind side float. This system has the great advantage of avoiding pumps on board, and the excluding of pipes connected to the arms of the side floats. In this case the side floats need a valve to discharge quickly the embarked water (see fig.13) VARIATIONS
Throughout the description of this invention, the word "equipped", "have", "has", are not intended to exclude other additives, components integers or steps.
A variation of this invention is to rotate the side floating in counter clock wise, when the vessel is in mooring condition. In this case the draft of the vessel is totally duet to the length of the rudder/rudders.
STATEMENT OF TECHINCAL ADVANTAGES a) LESS WEIGHT : With the elimination of the fixed keel/ballast, the vessel with the present invention is lighter up to 40%
b) BALLAST VARIABLE: since the ballast is totally variable, even in very light wind conditions, there is no extra weight on board that could penalize the vessel's performance c) SAFETY : even in case of gusts, stormy weather or crew mistakes, the leeward side float touches the water surface, thus increasing immediately the righting moment of the vessel
d) LESS WETTED SURFACE: the present invention is based on the concept that the side floats are completely independent in rotation and positioned one to each other, therefore the side float leeward, that is empty, is rotated in order to be out of the sea water. This aspect is fundamental to ensure lowest wetted surface, permitting top performance.
e) COMFORT: during anchorage there is a further advantage: the possibility to leaving the side floats both empty in the water guaranteeing greater stability and avoiding the constant heeling of the vessel.
f) LESS PITCHING: the absence of fixed keel/ ballast reduces the vessel's pitching in sailing condition
g) LESS DRAFT: the use of retractable arms, and canards, greatly reduce the draft; this creates great advantages in mooring conditions
h) UNSINKABLE: the side float, equipped with air bags, guarantee the unsinkablility to the vessel
i) LESS COSTLY: lead, which is very expensive, is no longer required
j) DECREASED ANGLE OF HEEL
k) DECREASED DRAG
I) INCREASED PERFORMANCE AND STABILITY
m) MORE SPEED, the side float, equipped by lifting hydrofoil, creates a vertical force that support the vessel, with the result of even less wetted surface