WO1997000804A1

WO1997000804A1 - Balancing system for sailing boats

Info

Publication number: WO1997000804A1
Application number: PCT/IT1996/000119
Authority: WO
Inventors: Pietro Immordino
Original assignee: Pietro Immordino
Priority date: 1995-06-21
Filing date: 1996-06-13
Publication date: 1997-01-09

Abstract

This invention refers to single hull/pluri-hull sailing boats. In the case of single hull boats, two suitably shaped floats are laterally applied to the hull. They slide from top to bottom along suitable guides; in the case of pluri-hull boats, the lateral hulls will laterally slide from top to bottom along suitable guides. This device includes a sail mast moving in function of the wind lateral thrust on sails and the mast movement makes the lee float or hull sink. The lee float or hull sinking is used to oppose both the boat heeling and drift. The effects of the invention application are: improvement of the boat comfort and safety conditions, increase of sailage efficiency and optimisation of hull hydrodynamic performances.

Description

DESCRIPTION

BALANCING SYSTEM FOR SAILING BOATS

TECHNICAL FIELD

Sailing boats with one or more hulls, one or more masts, where the wind pres- sure on sails moves the sail mast versus the hull were it insists. On its turn, the mast movement moves the means opposing the heeling and drift versus the boat hull(s).

Means opposing the boat heeling and drift are constituted (for a single hull boat) by specific suitably shaped floats. They are arranged on the boat two sides. When the wind exerts a pressure on sails which makes the boat heel, the mast moves and transmits its movement to the lee float which dips into the water, in order to oppose the boat heeling.

In the case of boats with more hulls, the same effect is accomplished dipping into the water the lee hull.

Means opposing the heeling due to the wind action on sails are used also to op- pose the lateral thrust (drift) acting on the hull.

The connection between the sail mast and the means opposing the heeling is made in order to allow a lee float or lee hull dipping which is compatible with a boat trim with little or no heeling.

The movement ofthe mast and ofthe means opposing the heeling and drift are performed without any crew's intervention.

PRIOR ART

Generally speaking, the sail boats are subject to a heeling due to the wind pres¬ sure on sails. This heeling is partly or fully adjusted by the crew's windward move¬ ments. U.S. Patents 3,985,106 dated 12 Oct. 1976 and 4,094,263 dated 13th June

1978 and the PCT/N091/00086 dated 17th June 1991 (WO 91/19641 dated 26th De¬ cember 19 1) describe some devices which adjust the heeling of a single hull boat through the automatic movement ofthe ballast induced by the mast movement.

U.S. Patent 4,286,533 ofthe 1st September 1981, describes a device where the adjustment ofthe heeling effect is achieved through the mast windward movement, implemented by the crew's intervention, and the movement ofthe very crew.

In all above patents there is no adjusting dipping ofthe balancing system. This dipping, in the case of this patent device, is used for making the heeling up and also for limiting the boat lateral drift. The fact of dipping means opposing the boat drift only when this is actually nec¬ essary, constitutes an advantage similar to the one of small boats with sliding keel, where the crew lowers the sliding keel only under sailing conditions which get this operation necessary. DISCLOSURE OF THE INVENTION

This invention refers to a single or pluri-hull sailing boat, where the sail mast moves versus the hull where it insists. The mast movement is transmitted through suitable devices to means opposing the boat heeling. These opposing means are constituted (for a single hull boat) by specific suita¬ bly shaped floats. They are arranged on the two sides ofthe boat. The lee float is dip according to the wind pressure on sails, so as to oppose the heeling action exerted by the wind on sails.

In the case of boats with more hulls, the same effect is accomphshed dipping the lee hull into the water. This hull moves from top to bottom versus the system connect¬ ing boat hulls.

Devices transmitting the mast movement to means opposing the heeling are im- plemented in order to warrant boat saihng trims allowing a good sail efficiency, a cor¬ rect hydrodynamic trim and a safe boat speed.

Furthermore, the sail mast can move partially independently by means opposing the heeling, in case of sudden gusts, to reduce the sail area exposed to the wind.

Even though the following description and drawings refer to a single mast boat, this invention is apphcable, as a sectorial engineer will clearly understand, even to pluri-masted boats.

SHORT DESCRIPTION OF DRAWINGS

This invention will be later explained, referring to drawings shown on the en¬ closed figures Nos. 1, la, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11. This invention is apphcable both to single hull boats and to pluri-hull (trimaran) boats. The above drawings show also three different actuation types, apphcable to both types ofthe above boats.

The graphic plotting of detailed sailage equipment and sails was omitted in all mentioned figures for simplicity sake of drawing and clearness of explanation. Fur¬ thermore, in figures the stretching device keeping the lee shroud stretched when sail- ing, is not shown.

Drawings of figures 1, 2, 3 and 4 show the invention as apphed to a single hull boat in the first actuation type; basically:

- Figure 1 is the cross section of a single hull boat in a rest state, with the in¬ vented device drawn, due to exposition clearness reasons, referring to a single shroud; - Figure la is a cross section showing the constructive details of the pre- stretched spring M2. In all other figures, this spring is shown schematically only;

- Figure 2 is the front view ofthe same boat shown at Fig. 1, at rest, with the invented device apphed to both shrouds;

- Figure 3 is the front view of the same boat shown at figures 1 and 2, under normal sailing conditions, with the invented device appUed to both shrouds;

- Figure 4 is the front view ofthe same boat shown at figures 1, 2 and 3, sub¬ jected to strong wind gusts, with the invented device apphed to both shrouds;

Figures Nos. 5, 6, 7 and 8 show the invention apphed to a trimaran-typed boat, w h the same actuation type of figures 1, 2, 3 and 4, and exactly: - The Figure 5 is a front view of a boat with a trimaran hull, under rest condi¬ tions, with the invented device drawn, due to exposition clearness reasons, referring to a single shroud;

- Figures 6, 7 and 8 are the front views ofthe boat shown at Figure 5, with the invention device appUed to both shrouds, under rest conditions, normal sailing condi¬ tions and gusts conditions, respectively.

Figures Nos. 9 and 10 show the invention applied to a trimaran-typed boat, with a different actuation type, consisting in making the mast transversely translate to the hull longitudinal axis, instead of rotating it around its end, and exactly: - Fig. 9 is the front view ofthe boat under normal sailing conditions, with the applied invention device, due to exposition clearness reasons, referring to a single shroud;

- Fig. 10 is the front view ofthe boat, under the same sailing conditions, with the device apphed to both shrouds. Instead, Fig. 11 shows the invention apphed to a single hull boat with a third actuation type, consisting in transmitting the motion of the mast to the lee float through a system constituted by hydraulic cylinders and pipelines, instead of cables, pulleys and hoists, and exactly:

- Fig. 11 is the cross section ofthe boat under normal sailing conditions, with the invented device drawn, due to exposition clearness reasons, referring to the single windward shroud.

The three actuation types ofthe invention shown on the above drawings are, as it can clearly result to a sectorial engineer, all apphcable both to a single hull boat and to pluri-hull boats, even if only for the first ofthese types the device was drawn refer- ring to both types of boats.

MODALITIES OF APPLYING THE INVENTION

1 - FIRST TYPE OF ACTUATION la - INVENTION APPLIED TO A SINGLE HULL BOAT

Figures 1, 2, 3 and 4 graphically describe the invention apphed to a single hull boat.

On Figure 1, the used device was drawn, in order to get its understanding eas¬ ier, only referring to the windward shroud S2; instead, in figures 2, 3 and 4, the device was drawn referring to both shrouds.

Referring to Figure 1, the device basically includes: - a mast T able to rotate around a longitudinal pivot O;

- a system transm-tting the strength from the shroud S2 to the boom Al, includ¬ ing the hoist P2, the cable F2 and the pulley Rl ;

- a boom Al, placed on the top of float Gl, free of sliding from top to bottom versus the boat hull and integral to the below float Gl ; - a shaped float Gl placed on the boat lee side;

- a pre-stretched spring M2 placed on the shroud S2. Fig. la shows a constructive detail of the spring M2, which is pre-stretched between pins Nl and N2, inserted into cylinders Cl and C2; when the stretching on the shroud exceeds the pre-stretching of spring M2, the very spring extends, the two cylinders shde one inside the other and the mast tilts owing to the shroud extending. Under normal sailing conditions, the wind pressure on sails tends to make the mast T rotate around the pivot O, and the shroud S2 is stretched and tends to extend transmitting the strength exerted on it by the mast to the cable F2, interposing the hoist P2; on ks turn, the cable F2 transmits the strength to the boom Al, sliding from top to bottom on its guide, making the float Gl dip, whose floating thrust balances the lateral wind thrust on sails. In this manner, the float acts also as a sliding keel for the boat, limiting the wind lateral thrust on sails (fig. 3).

Under these conditions, the system allows some mast tiltings within limits fit to achieve good efficiency of sailage and boat safe speeds, through a proper dimension¬ ing ofthe springs Ml and M2, ofthe reduction ratio of hoists Pl and P2, ofthe shape and volume of floats Gl and G2.

When the wind strength exceeds the allowed limits for a safe sailing with the used sailage, the pre-stretched spring M2 extends according to the increase of stretching in the shroud S2 where it insists, allowing the mast T to furtherly tilt to the hull, avoiding that the sinking ofthe float Gl remarkably dips (fig. 4). The behaviour of the described device allows the boat to win any wind gusts with no hull over-heeling and conditions of high safety to the capsizing.

lb - INVENTION APPLIED TO A PLURI-HULL BOAT

Figures Nos. 5, 6, 7 and 8 graphically describe the invention as apphed to a pluri-hull boat (trimaran). On Figure 5, the used device was drawn, in order to get its understanding eas¬ ier, only referring to the windward shroud S2; the strength transmitted by the mast T to the windward shroud S2 is sent back, through the hoist P2, the cable F2 and the pulley Rl to a boom Al, free of vertically sliding to the beam V connecting the main huh. This boom Al is integrally connected to the below lateral hull Ll . Even in this case, a pre-stretched spring M2 was positioned on the shroud S2.

The spring aims at limiting the strength transmitted by the shroud S2 to the lateral hull Ll.

Figures Nos. 6, 7 and 8 show a boat front view with three different sailing trims and the device mounted on both shrouds Sl and S2. Figure 6 shows the boat with no heeling moment.

Figure 7 shows the boat imder normal sailing conditions; the rotation of the mast T to the longitudinal pin O causes a consequent sinking ofthe lee hull Ll, until when the floating thrust of this hull doesnt makes up the strength transmitted by the mast T to the windward shroud S2. The median hull is submitted to a limited or null heeling due to the compensat¬ ing action ofthe floating thrust ofthe lee hull Ll .

When, due to the increase ofthe wind strength, the strength on the windward shroud S2 exceeds the pre-stretching value ofthe spring M2, this very spring extends, allowing the mast T to make a further rotation, in a manner partially independent by the sinking ofthe lee hull Ll (fig. 8). In this manner, even in the examined event, inserting the two springs Ml and

M2, one achieves the result of aUowing the mast T wide rotations along the pin O. In this manner, the wind effect on sails is reduced, when the wind strength exceeds limits aUowed for a safe sailing, contemporaneously limiting the lee huU sinking to values compatible with a proper sailing trim.

2 - SECOND TYPE OF ACTUATION

Figures 9 and 10 show the second type of actuation ofthe invention appUed to a trimaran huU.

Fig. 9 is the boat front view, under normal sailing conditions, showing the in- vented device, in order to get its understanding easier, referring to the windward shroud S2 only.

The mast T is placed on a slide W, to which is integral both for translation and rotation; the slide moves transversaUy to the boat huUs, shding on suitable shdes placed on the connection between hulls. The shde lateral movement involves the stretching ofthe shroud S2.

On its turn, the shroud is connected to the boom Al, through the hoist P2, the cable F2 and the puUey Rl; the boom Al moves from top to bottom to the connection beam V. The boom Al integral to the below huU Ll causes the sinking of this latter, until when the floating thrust of this huU Ll doesn't makes up the strength transmitted by the mast T to the windward shroud S2. On the shde W are placed also the fixed points of sail tacks.

Fig. 10 shows the same boat at the same conditions of Fig. 9, but with the de¬ vice apphed to both shrouds.

The highest constructive problem of this second type of actuation is made up by the better sailage efficiency, since the sail mast can be kept vertical.

Obviously, this second type of actuation can be apphed also to a single hull boat.

3 - THIRD TYPE OF ACTUATION

Fig. 11 is the cross section of a single hull boat under normal sailing conditions, to which the third type of actuation was appUed; on the figure, the device is shown, due to exposition clearness, referring only to the windward shroud S2 only.

Referring to Fig. 11, the device includes:

- a system transmitting the force from the shroud S2 to the boom Al ofthe hy¬ draulic cylinder Zl, including the hoist P2 and the cable F2; - a hydraulic cylinder Zl, whose body is integral to the boat hull, on whose boom Al the cable F2 is fixed;

- a hydrauUc cylinder Z3, whose body is integral to the boat hull, whereas the related boom A3 is integral to the float Gl;

- a connecting pipeline Ul between cylinders Zl and Z3; - a cylindrical guide Dl sUding on the outer surface ofthe cylinder Z3.

The stretching ofthe shroud S2 induced by the wind action on sails, is transmit¬ ted through the hoist P2 and cable F2 to the boom Al controlling the piston of the hydrauUc cylinder Zl; the movement of the piston in the cylinder Zl is transmitted, through the pipeline Ul, to the piston ofthe hydraulic cylinder Z3 and the movement of this very piston pushes the boom A3 and float Gl connected to it, downward.

Even this third type of actuation can be naturally apphed to a pluri-huU boat.

FURTHERTYPESOFACTUATION In aU three previous types of actuation, the insertion of springs and shock ab¬ sorbers into the device transmitting the strength, is provided for. This serves to achieve some given mast shiftments, in function ofthe boat heeling.

Devices lim-ting the wind action on sails under anomalous conditions (mechanical springs Ml and M2) can be replaced using other types of pre-stretched hydraulic or pneumatic springs.

Basically, the execution details ofthe device can be changed without exceeding the invention limits and then the patent limits.

RESULTS IN APPLYING THE INVENTION

The main results related to the invention applying are: - higher safety of the hull at level of a possible capsizing of its;

- higher safety and feasibility of deck operations by the crew, owing to the ab¬ sence of heeling in the trampling surfaces;

- better hull comfort, due to the lower or null heeling of trampling surfaces or furniture; - lower risk that stowed charges may move;

- better sailage efficiency;

- better hull hydrodynamic behaviour, since it can be designed only for a nuU heeling sailing;

- better boat hydrodynamic behaviour, since during stem paces there are no dip drift surfaces, floats or lateral hulls being all up. During other paces the lee float or lee hull sinking is proportional to the wind lateral thrust (this corresponds to the sUding keel depth adjustment performed by the crew on boats equipped with sUding keels);

- There is also the possibiUty to implement very large gliding boats, owing to the pressure reduction exerted by the water on the huU when the lee hull or float are plunged.

Whatever the used heeling adjusting system is, the device can be calibrated in order to have a boat preset behaviour during the sailing; for instance, one can choose to partially or fiiUy make up the wind heeling effect on sails or even, make the hull tilt windward. This changing strength transmission ratioes from the shroud to the float or the lateral hull, the float or hull shape and volume, the tilting of the guide of the boom pushing the float or the lateral hull.

Similarly, the device limiting the shroud strength can be calibrated using differ¬ ent parameters, according to the fact one wishes to have a higher sailage efficiency or a higher hull safety, or else.

The wide range of possibilities for the usable arrangements of this device, (mentioned above) aUow to suggest it can be apphed on boats of all types, costs and dimensions; in fact, this device could open unexplored ways to the sailing. It should be noted that the boat heeling adjustment is achieved without burden¬ ing the huU with baUast. This gives remarkable advantages at level of speed and of hull constructive techniques, as weU as of hull lightness.

A big advantage ofthe device consists in the fact it works fully automaticaUy, without no need of crew's interventions; this operation is for both the opposing ac¬ tions achieved by sinking the lee float or huU, that is making up both the heeling effect and the boat drift induced by the wind thrust on sails.

Claims

1. A system opposing the heeling and drift of single hull saiUng boats, including one or more lateraUy tiltable masts, both lateral shrouds connected to hoists, puUeys and wires in order to transmit the strength acting on shrouds to boat heehng and drift means. It is characterised by the fact that:

- boat drift and heeling balancing systems include two properly shaped floats, whose the lee one shdes to the huU along mechanical guides from top to bottom, pro¬ gressively dipping into the water;

- the above floats are shaped in order that, when they are dip, they oppose both the boat heeling and boat drift;

- the float dipping occurs in function ofthe wind strength acting on sails, it re¬ ceived by the system of wires, pulleys and hoists and with no need of crew's interven¬ tions.

2. A system opposing the heeling and drift of single hull sailing boats, including one or more masts, that trasversally shdes to the hull, laying on a suitable shde, where also the fixed points of sail tacks insist, both lateral shrouds connected to hoists, pul¬ leys and wires in order to transmit the lateral strength acting on sails to the boat heel¬ ing and drift balancing systems. It is characterised by the fact that:

- the shde supporting the mast(s) and the fixed points of sail tacks moves in function ofthe wind strength acting on sails and with no need of crew's interventions, sUding on its sUdes;

- boat drift and heeling balancing systems include two properly shaped floats, whose the lee one shdes to the huU along mechanical guides from top to bottom, pro¬ gressively dipping into the water; - the above floats are shaped in order that, when they are dip, they oppose both the boat heeling and drift;

3. A system opposing the heeling and drift of pluri-huU sailing boats, including one or more laterally tiltable masts, both lateral shrouds connected to hoists, pulleys and wires in order to transmit the strength acting on shrouds to boat heeling and drift means. It is characterised by the -act that:

- boat drift and heeling balancing systems include properly shaped lateral hulls, whose the lee one shdes to the median hull along mechanical guides from top to bot¬ tom, progressively dipping itself into the water;

- the previously mentioned hulls (as per previous paragraph) are shaped in order that, when they are dip, they oppose both the boat heeling and drift;

- the lee huh dipping occurs in function of the wind strength acting on sails, it received by the system of wires, puUey and hoists and with no need of crew's inter¬ ventions.

4. A system opposing the heeling and drift of pluri-hufl sailing boats, including one or more masts, that transversaUy sUdes to the hulls, laying on a suitable shde, where also the fixed points of sail tacks insist, both lateral shrouds connected to hoists, puUeys and wires in order to transmit the lateral strength acting on sails to the boat heeling and drift balancing systems. It is characterised by the fact that:

- the shde supporting the mast(s) and the fixed points of sail tacks move in function ofthe wind strength acting on saUs and with no need of crew's interventions, sliding on its sUdes;

- boat drift and heeling balancing systems are constituted by suitably shaped lateral huUs, whose the lee one sUdes to the median hull along mechanical guides from top to bottom, progressively dipping into the water;

- the above huUs (as per previous paragraph) are shaped in order that, when they are dip, they oppose both the boat heeling and drift;

- the lee hull dipping occurs in function ofthe wind strength acting on sails, it received by the system of wires, pulleys and hoists and with no need of crew's inter¬ ventions.

5. Sailing boat according to claims 1, 2, 3 and 4, characterised by the presence of shrouds where a spring-driven device (mechanical, hydrauUc or pneumatic springs) is inserted. That spring makes the shroud extension when the stretching strength act¬ ing on them exceeds a preset value, so aUowing the sail mast(s) tilting;

6. Sailing boat according to claims 1, 2, 3, 4 and 5, characterised by the pres¬ ence of shrouds where a spring or elastic device, keeping lee shrouds stretched during the sailing, is inserted.

7. SaiUng boat according to previous claims, characterised by the fact that into the device transmitting the mast motion to the means adjusting the heeling, due to the wind action on sails, opposing and adjusting devices of the movement width and shock absorbing (springs and shock absorbers) are inserted. This serves in order to have a given boat behaviour in function of the wind strength and of wind gusts.