WO2001012503A1

WO2001012503A1 - Boat rigging system

Info

Publication number: WO2001012503A1
Application number: PCT/GB2000/003190
Authority: WO
Inventors: Mark Anthony Wagner
Original assignee: Datametrix Limited
Priority date: 1999-08-17
Filing date: 2000-08-17
Publication date: 2001-02-22
Also published as: GB2353263A; GB2353263B; GB9919470D0; AU6462100A; GB0020223D0

Abstract

A rigging system for a mono-hull, catamaran or tri-maran sailing boat wherein the leading edge of mainsail (14) is attached to a tensioned sail support wire (11) suspended from apex (10) of a tripod frame (7, 8, 9) mounted on the hull (1, 2). The wire (11) is anchored at (19) to the boat and tensioned by means (13) to be substantially vertical relative thereto. The boom (12) is attached intermediate its ends to the support wire (11) intermediate its ends so as to pivot about said wire (11) and provide a rotating boom, the mainsail (14) and foresail (15) being attached to said boom. An A-frame (30, 31) or single inclined spar (36) can be used instead of the tripod (7, 8, 9) to support the sails.

Description

BOAT RIGGING SYSTEM

This invention relates to a novel form of rigging for sailing boats such as mono-hulls, catamarans or trimarans and more particularly to a form of rigging which dispenses with the need to provide a conventional mast to which the mainsail is attached.

The speed and performance of a boat can be improved considerably if the adverse effect of the mast on the airflow around the sail is reduced because the presence of the mast at the leading edge of the sail determines to a large extent the nature of the air flow around the sail. Its effect is particularly harmful in that it creates an area of dead air on the leeward side of the sail as a result of which, the boat is unable to point as high up into the wind as it would if the adverse influence of the mast were eliminated. Rig designers are therefore always looking for ways to reduce the drag and turbulence created by the mast.

Another area of interest for boat designers is to try to find ways to reduce the number of people needed to sail a boat. In larger boats, managing the sails and resetting them normally requires several people so developing rigging and sail systems which can be operated by one person from the cockpit is highly desirable. One well known way of reefing a sail is to use a roller reefing system which rotates the tube or stay to which the sail is attached using a drum winch which rolls the sail around itself. These roller reefing systems have been in use for many years but are most commonly used for reefing foresails such as jibs or genoas as they have been found to work extremely satisfactorily. Such systems have not found such widespread acceptance for mainsail roller . ~> -

reefing systems as the roller reefing mechanism has to be housed within the mast increasing the expense and weight of the rig. Furthermore, an access slot to said mechanism has to extend along the length of the rear side of the mast which reduces its structural rigidity. It has also been found that such systems may jam, particularly under load in windy conditions.

It is therefore a primary object of the invention to provide a rigging system for a boat which dispenses with the need to use a conventional mast and instead supports the mainsail in a novel manner which increases its aerodynamic efficiency and thereby enables the boat to be sailed closer to the wind. It is a further object of the invention to provide a rigging system for a boat which enables all of its sails to be reefed using roller reefing systems of the type currently used for foresails.

It is a still further object of the invention to provide a rigging system which can be readily retro-fitted to a conventionally rigged boat.

According to one aspect of the invention there is provided a rigging system for supporting a sail on a boat comprising a sail support structure mountable on the hull or hulls of the boat, sail support means extending between said sail support structure and the boat to which the leading edge of a sail can be attached, a boom attached intermediate its ends to said sail support means intermediate the ends thereof and pivotable amount said sail support means and anchoring means attachable to the boat to tension the sail support means substantially vertically and anchor the base thereof to the boat. The sail support structure can be an A-frame comprising a pair of spars which meet at an apex, the foot of each spar being mountable either amidships on opposite sides of the boat or alternatively at the bow and stern, the A frame being supported by rigging.

Alternatively, the foot of each spar can be mounted at one end of the boat, conveniently the stern, and a third spar is attached to the apex of the A-frame, the foot thereof being mountable on the opposite end of the boat, i.e. the bow to provide a tripod frame. 4 spars could however be used, two at the stern and two at the bow. A single spar inclined to the vertical can also be used.

The rigging system of the invention can be used on trimaran, catamaran or mono-hulls.

The boom can be attached to an end of the sail support means whereby it is suspended above the deck, secondary means being connected between the boom and the deck to anchor the boom thereto. Alternatively, the sail support means can extend directly to the deck, the boom being attached thereto intermediate its ends and intermediate the ends of the sail support means.

The front bottom corner of a secondary sail such as a jib or genoa can be anchored to the forwardly extending portion of the boom, the head of the secondary sail being attachable to the sail support structure and the clew or lower rear corner of the secondary sail being attachable to the forwardly extending portion of the boom by a sheet so that the trailing edge of the sail is movable laterally relative to the boom.

Conveniently the leading edge of the secondary sail is attachable to a forestay which runs from the front of the boom to the apex of the sail support structure.

Preferably, the tensioned sail support means and the secondary sail forestay form part of roller reefing systems.

Rigging systems of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a rigging system of the invention fitted to a Catamaran;

Figure 2 is a plan view of the boat and rigging system shown in Figure 1;

Figure 3 is a side view of the boat and rigging system shown in Figures 1 and 2;

Figure 4 is a side view of a rigging system of the invention fitted to a mono-hull vessel;

Figure 5 is a front view of Figure 4;

Figure 6 is a plan view of Figures 4 and 5;

Figure 7 is a side view of an alternative form of rigging of the invention fitted to a mono-hull vessel;

Figure 8 is a plan view of the vessel shown in Figure 7; and

Figure 9 is a front view of the vessel shown in Figures 7 and 8. Referring now to the drawings, there is shown a Catamaran comprising a pair of spaced hulls 1 and 2 which are connected together adjacent their bow by means of a cross spar 3, the rear end being connected by deck 4. A cabin 5 with a cockpit 6 therein is mounted on the deck 4.

As can be seen from the drawings, mainsail 14 and foresail 15 are supported on the boat in a novel way in that they are suspended from apex 10 on a sail support structure in the form of a tripod frame comprising spars 7, 8 and 9. These spars can be made from any suitable material such as wood, aluminium or carbon fibre and can be much thinner than a conventional mast as the load on the sails will be spread between all three spars and the spars will not be subjected to bending loads as a conventional mast would. Spar 7 is attached to the bow of the boat at the mid-point of the cross spar 3 whereas rear spars 8 and 9 are attached to the rear of the boat on hulls 2 and 1 respectively.

One end of sail support means in the form of wire 11 is attached to the apex 10 of the tripod frame 7,8,9 and extends downwardly therefrom towards the deck 4 where it is attached at 17 to boom 12. The boom is thereby suspended from the apex 10 and has a front portion 12 A which extends forwardly of the wire 11 to provide a "rotating rig" .

The boom 12 is anchored to the deck 4 by a secondary wire 11 A which is attached to the underside of the boom 12 at 17A and extends to the deck 4 where it is anchored at 19. Known tensioning means 13 such as a bottle screw fitting can be included in the secondary wire 11A to enable it to be tensioned. As an alternative, a single wire 11 can extend between the apex 10 and the deck 4 where it is anchored at 19, the boom 12 being attached to the wire 11 intermediate its ends to pivot about the wire and thereby provide a "rotating rig" . Known tensioning means such as a bottle screw fitting can be included in the section of the wire that extends between the deck 4 and the apex 10. It is extremely important that the wire 11 is tensioned to a very high level otherwise the leading edge or luff of the sail 14 will bow under load and lose its aerodynamic efficiency and the spars 7,8,9 will not be in compression.

The mainsail 14 is attached to the boom 12 in known manner by means of a rope or outhaul 20B extending between the rear 20A of the boom 12 to the lower rear corner or clew 20C of the mainsail 14. The leading edge or luff of the main sail 14 is also attached to the wire 11 in any suitable known manner which enables it to be roller reefed around the mast wire 11 using a drum winch 26 in known manner. No further description of the roller reefing system will therefore be given here.

A forestay 16A extends between the apex 10 of the frame 7,8,9 and a rear stay 16B extends from the apex 10 to the rear 20A of the boom 12, both of which include means such as known bottle screws to tension them. The front lower corner 20 of the foresail 15 is attached to the boom 12A and the clew or lower rear corner of the sail is attached by means of rope or sheet 21 to a cross member 22 to allow the foresail 15 to move laterally with respect to the boom 12A in known manner. The foresail 15 is attached to the forestay 16A in known manner to allow it to be roller reefed thereon by means of a drum winch 26A. As this roller reefing system is well known, no further description thereof will be given here. The boom 12 and both sails are controlled by means of a single main rope or sheet 23 which has a fitting 24 at its remote end which is received in a known fitting (not shown) on the deck 4 to allow the boom to move laterally with respect thereto.

Although the secondary wire 11A beneath boom 12 is illustrated in all of the Figures as being located directly below the apex 10 of the sail support structure, this is not essential as it can be anchored to the deck at other locations fore or aft or from side to side of the anchor point 19 as required. The attachment point on the boom 17A also need not be in line with the wire 11.

Referring now to Figures 4-6, there is shown a sail support structure in the form of an A-frame comprising spars 30 and 31 whose bases are mounted on opposite sides of hull 1 and whose tops meet at an apex 10. The spars 30,31 can be made from any suitable material such as wood, aluminium or carbon fibre and can be much thinner than a conventional mast as the load on the sails will be spread between both spars and the spars will not be subject to bending loads as would be the case in a conventional mast. The spars 30,31 are strengthened by spaced cross braces 34 and 35 and tensioning cross wires 34A,34B and 35A,35B. A forestay 32 extends from the apex 10 of the A-frame 30,31 to the front of the boat and a back stay 33 extends from the apex 10 to the rear of the boat to hold the A-frame upright.

One end sail support means in the form of wire 11 is attached to the apex 10 of the A-frame 30,31 and extends downwardly therefrom towards the deck 4 where it is attached at 17 to boom 12. The boom is thereby suspended from the apex 10 and has a front portion 12A which extends forwardly of the wire 11 to provide a " rotating rig" .

The boom 12 is anchored to the deck 4 by a secondary wire 11A (see Figure 5) which is attached to the underside of the boom 12 at 17A and extends to the deck 4 where it is anchored at 19. Known tensioning means 13 such as a bottle screw fitting can be included in the secondary wire 11A to enable it to be tensioned. As an alternative, a single wire 11 can extend between the apex 10 and the deck 4 where it is anchored at 19, the boom 12 being attached to the wire 11 intermediate its ends to pivot about the wire 11 and thereby provide a "rotating rig". Known tensioning means such as a bottle screw fitting can be included in the section of the wire that extends between the deck 4 and the apex 10. It is extremely important that the wire 11 is tensioned to a very high level otherwise the leading edge or luff of the sail 14 will bow under load and lose its aerodvnamic efficiency and the A-frame 30,31 will not be in compression.

The mainsail 14 is attached to the boom 12 in known manner by means of a rope or outhaul 20B extending between the rear 20A of the boom 12 to the lower rear corner or clew 20C of the mainsail 14. The leading edge or luff of the main sail 14 is also attached to the wire 11 in any suitable known manner which enables it to be roller reefed around the wire 11 using a drum winch 26 in known manner. No further description of the roller reefing system will therefore be given here.

A forestay 32A extends between the apex 10 of the A-frame 30,31 and is attached at 20 to the front of the boom 12. The front lower corner 20 of the foresail 15 is attached to the boom 12A and the clew or lower rear corner of the sail is attached by means of rope or sheet 21 to a cross member 22 to allow the foresail 15 to move laterally with respect to the boom 12A in known manner. The foresail 15 is attached to the forestay 32A in known manner to allow it to be roller reefed thereon by means of drum winch 26 A. As this roller reefing system is well known, no further description thereof will be given here.

The boom 12 and both sails 14 and 15 are controlled bv means of a main rope or sheet 23 which allows the orientation of the boom relative to the wind to be adjusted.

Referring now to Figures 7-9, there is shown a sail support structure in the form of a single spar 36 which is inclined to the vertical and held in position by forestay 32 and backstay 33. Spreader 37 with shrouds 38 and 39 place the spar 36 in compression and hold it in position on the hull. Spar 36 can be made from any suitable material such as wood, aluminium or carbon fibre. A forestay 32 extends between the bow of the boat and apex 10 and rear stay 33 extends between the stern of the boat to hold the spar 36 in its illustrated position inclined to the vertical both of which include known bottle screws to tension them.

One end of sail support means in the form of wire 11 is attached to the apex 10 of the spar 36 and extends downwardly therefrom towards the deck 4 where it is attached at 17 to boom 12. The boom is thereby suspended from the apex 10 of the spar 36 and has a front portion 12A which extends forwardly of the mast wire 11 to provide a "rotating rig" . The boom 12 is anchored to the deck 4 by a secondary wire 11A which is attached to the underside of the boom 12 at 17A and extends to the deck 4 where it is anchored at 19. Known tensioning means 13 such as a bottle screw fitting can be included in the secondary wire 11A to enable it to be tensioned. As an alternative, a single wire 11 can extend between the apex 10 and the deck 4 where it is anchored at 19, the boom 12 being attached to the wire 11 intermediate its ends to pivot about the wire 11 and thereby provide a "rotating rig". Known tensioning means such as a bottle screw fitting can be included in the section of the wire that extends between the deck 4 and the apex 10. It is extremely important that the wire 11 is tensioned to a very high level otherwise the leading edge or luff of the sail 14 will bow under load and lose its aerodynamic efficiency.

The mainsail 14 is attached to the boom 12 in known manner by means of a rope or outhaul 20B extending between the rear 20A of the boom 12 to the lower rear corner or clew 20C of the mainsail 14. The leading edge or luff the main sail 14 is also attached to the wire 11 in any suitable known manner which enables it to be roller reefed around the wire 11 using a drum winch 26 in known manner. No further description of the roller reefing system will therefore be given here.

A forestay 32A extends from the apex 10 of the spar 36 to the front of the boom 12A. The front lower corner 20 of the foresail 15 is attached to the boom 12A and the clew or lower rear corner of the sail is attached by means of rope or sheet 21 to a cross member 22 to allow the foresail 15 to move laterally with respect to the boom 12A in known manner. The foresail 15 is attached to the forestay 32A in known manner to allow it to be roller reefed thereon by means of a drum winch 26A. As this roller reefing system is well known, no further description thereof will be given here.

The boom 12 and both sails 14 and 15 are controlled by means of a main rope or sheet 23 which allows the orientation of the boom relative to the wind to be adjusted.

It will be appreciated from the foregoing description of the various rigging system shown in the drawings that because both sails 14 and 15 are attached to the boom 12 which rotates about the wire 11 or 11A relative to the hull, the optimum gap or slot between the two interacting sails 14,15 will be maintained regardless of the heading angle relative to the wind direction. The main advantage of this rotating rig arrangement is that the person sailing the boat does not need to do anything to the foresail 15 when the heading of the boat is changed relative to the wind or the boat goes about as the sail will simply change its orientation and move across the spar 22 automatically. More significantly, the slot or gap between the sail 15 and the sail 14 is maintained constant at all times which substantially increases the performance of the rig especially when sailing off the wind. A further advantage of this rigging system is its ability to be de-powered quickly in an emergency because the boom 12 can be released by letting go of the main sheet 23 and allowing the sails to align with the wind very quickly. As the boom 12 can rotate throughout 360° because it is suspended from the apex 10 of the sail support structure, i.e. tripod 7,8,9, the sails can very quickly align with the wind and the boat can speedily be brought to a stop. This is particularly useful when manoeuvring in confined spaces. A further advantage of the rigging system of the invention is that it needs fewer components such as winches as a single sheet 23 with its associated winch is all that is needed to control both sails 14 and 15.

Other advantages of the rotating rig are as follows:

1. Only one rope or sheet 23 is needed to control both sails.

2. A self tacking mainsail 14 and jib 15 is provided. 3. Deck gear (winches etc.) is reduced compared to a conventional rigging system.

4. Rope/sheet loads are reduced because of balance around the wire 11.

5. Gybing is much safer due to balance around the mast wire 11. 6. With the sails suspended from the sail support structure, i.e. tripod 7,8,9, it is possible to sail on any point of the wind because there is no central rigid mast to restrict the degree of rotation of the sails. With a conventional single mast, the sails can only pivot through a 180° arc because further rotation is prevented by the stays holding up the mast whereas with the rig of the present invention, the sails can rotate through 360°.

7. Power can be quickly applied to or released from the sails.

8. Power on a reach or run is increased using less sail

9. No specialised off wind sails are needed with their associated gear and storage space.

The advantages of the rigging system of the invention illustrated in the drawings are as follows: 1. Because none of the spars 7,8,9 (tripod), 30,31 (A-frame) or single spar 36 need to have tracks in them to mount the sails as in a conventional mast, thev can be made of much thinner tube which substantially saves on weight, size, cost and drag.

2. Because the spars are in pure compression at all times, complex structuring of the spars 7, 8 and 9 (tripod), 30,31 (A-frame) or spar 36 to cope with varying stresses is not required as is the case with a conventional mast. The spars can therefore be simple tubes of uniform cross section made from any light but strong material such as wood, carbon fibre or aluminium.

3. Because the load applied to the sails in the case of the tripod 7,8,9 or A-frame 30,31 is split between two of the spars at any time, the loading at the foot is at least half of that of a conventional single mast.

4. A much simpler rigging system can be employed reducing high up 0 weight, expense and deck clutter.

5. The fully rotating rig has the advantages of allowing single sheet control, a self tacking mainsail and jib and all the other advantages already referred to above. >

Because the luff of the leading edge of the mainsail is not attached to a conventional mast, the drag and turbulence created thereby is avoided so upwind performance will be significantly improved. . The ability to roller reef both sails with standard well known operating gear will ease sail handling enormously and reduce expense.

8. The rigging system can be retro-fitted to a boat having a conventional single mast very easily as there is no need to modify the hull to receive the new mast system because the mast spars 7,8,9 (tripod), 30,31 (A-frame) can be easily attached to the surface of the hull and there is no need for a complicated or space demanding mast box to be provided in the hull of the boat.

9. The rigging system of the invention can be made and sold separately as a ready made item as the only part of it which could need customising to a particular boat would be the length of the boom.

10. It should be possible to run all the control lines aft of the cockpit thereby reducing deck clutter and increasing safety.

11. The location of the apex 10 can easily be moved fore or aft by adjusting the length of the forestay 32 in the case of the A-frame sail support structure which facilitates obtaining a good steering balance by moving the centre of effort of the rig fore or aft. Releasing or loosening the forestay 32 also allows the A-frame sail support structure to be easily lowered towards the deck which can be useful in negotiating low bridges. 2. The centre of effort of the rig can also be easily moved by changing the location of its attachment 19 to the hull 1, assisting in properlv balancing the steering of the boat.

Claims

1. A rigging system for supporting a sail on a boat comprising a sail support structure mountable on the hull or hulls of the boat, sail support means extending between said sail support structure and the boat to which the leading edge of a sail can be attached, a boom attached intermediate its ends to said sail support means intermediate the ends thereof and pivotable about said sail support means and anchoring means attachable to the boat to tension the sail support means substantially vertically and anchor the base thereof to the boat.

2. A rigging system as claimed in claim 1 wherein the sail support structure is an A-frame comprising a pair of spars which meet at an apex, the foot of each spar being mountable on opposite sides of the boat.

15

3. A rigging system as claimed in claim 1 wherein the foot of one spar is mountable on the bow of the boat and the foot of the other spar is mounted on the stern of the boat.

4. A rigging system as claimed in claim 2 wherein the foot of each spar is mountable at one end of the boat and a third spar is attached to the apex of the A-frame, the foot thereof being mountable at the opposite end of the boat to provide a tripod frame.

2) 5. A rigging system as claimed in claim 4 wherein the feet of the A- frame spars are mountable at the rear of the boat and the foot of the third spar is mountable at the front end of the boat.

6. A rigging system as claimed in claim 1 wherein the sail support structure is a single spar which is inclined to the vertical.

7. A rigging system as claimed in any preceding claim wherein the sail is substantially triangular and has a leading edge which is normal to its base, the leading edge being attachable to the suspension means along its length.

8. A rigging system as claimed in any preceding claim wherein the boom is attachable to the sail support means whereby it is suspended from the sail support structure above the boat, secondary means being connectable between the boom and the boat to anchor the boom thereto.

9. A rigging system as claimed in claim 7 or claim 8 wherein the foot of the sail is attachable to the boom and the boom is controlled by a single main sheet connectable to the boat.

10. A rigging system as claimed in any preceding claim wherein the front bottom corner of a secondary sail such as a jib or genoa is anchored to the forwardly extending portion of the boom, the head of the sail being attachable to the sail support structure and the lower rear corner of the secondary sail being attachable to the forwardly extending portion of the boom by a sheet so that the trailing edge of the sail is movable laterally relative to the boom.

11. A rigging system as claimed in claim 10 wherein the leading edge of the secondary sail is attached to a forestay extending from the front of the boom to the apex of the sail support structure.

12. A rigging system as claimed in claim 11 wherein the sail support structure and the secondary sail forestay incorporate roller reefing systems.

13. A rigging system substantially as herein described with reference to the accompanying drawings.

14. A boat when fitted with a rigging system as claimed in any of claims 1-13.