WO2002034619A1

WO2002034619A1 - Device at a furlable sail for a sail-boat

Info

Publication number: WO2002034619A1
Application number: PCT/SE2001/002343
Authority: WO
Inventors: Mathias LINDSTRÖM
Original assignee: SELDéN MAST AB
Priority date: 2000-10-27
Filing date: 2001-10-26
Publication date: 2002-05-02
Also published as: SE0003932L; SE0003932D0; AU2002211156A1; SE516121C2

Abstract

Arrangement (1) for a sail (2) for a sailing boat (3) which exhibits preferably asymmetrical form and is so arranged as to be capable of being furled with the help of a roller, and there is a line (5) extending between the sail (2) and the roller, and the aforementioned roller is so arranged as to be capable of being caused to rotate, in conjunction with which the line (5) is so arranged as to be wound onto the roller. The aforementioned line (5) is attached to the sail (2) in such a way as to draw it together in the vertical sense (H) when the roller is caused to rotate in one direction. The sail (2) is so arranged as to be furled with the help of the aforementioned roller after drawing together the sail (2), and the furling is so arranged as to be effected around a rotatable leading edge (9) arranged between the roller (4) and the mast (8) only once the draw line (5) has been tensioned sufficiently. Furling of the sail (2) thus takes place automatically if a continuous pull is applied to the control line and when the draw line (5) is fully extended.

Description

Device at a furlable sail for a sail-boat

The present invention relates to an arrangement for a sail for a sailing boat which exhibits preferably asymmetrical form and is so arranged as to be capable of being furled with the help of a roller, and there is a line extending between the sail and the roller, and the aforementioned roller is so arranged as to be capable of being caused to rotate, in conjunction with which the line is so arranged as to be wound onto the roller.

Sails with asymmetrical form are known respectively as gennakers and spinnakers, and these sails are flying sails, i.e. the sail in question is not hoisted on a stay of any kind .

Historical background

Flying sails are used in downwind or quarter-wind sailing conditions, and their extremely domed shape enables them to pull the boat efficiently when the wind comes from the stern. The gennaker is a development of the spinnaker and has gained in popularity in recent years . There are three principal reasons for this.

The gennaker is easier to handle both when sailing and when setting/taking down the sail.

Because of its asymmetrical form, the gennaker is more efficient than the spinnaker with the wind abeam and when quartering.

A gennaker can be sailed higher against the wind than a spinnaker, including with the wind coming from slightly before the beam, which gives the gennaker a broader register than the spinnaker.

Other designations applied to the gennaker include family spinnaker or asymmetrical spinnaker. It is referred to as a family spinnaker because it is easier to handle than a conventional spinnaker and is thus ideally suited for family sailing and small crews. It is referred to as an asymmetrical spinnaker because of the form of the sail .

The gennaker differs from the spinnaker on the one hand in respect of its form (the spinnaker is entirely symmetrical, unlike the gennaker, and has more belly), and on the other hand in the way in which it is fixed and sheeted home. Both sails are referred to as "flying", i.e. ahead of/outside the forestay of the boat, up to a point above the forestay. The gennaker is attached at a fixed point at the front of the boat (in certain cases to a fixed or mobile bowsprit) and is sheeted home in the same way as a Genoa sail. The spinnaker, on the other hand, is "fixed" to a temporary spinnaker boom mounted on the mast and is sheeted home to both leeward and windward simultaneously. The windward sheet controls the angle of the spinnaker and the spinnaker boom to the wind, and the leeward sheet controls the form of the spinnaker. The gennaker can be ibed in the same way as a Genoa sail, since the tack is fixed at the extreme front of the boat. The spinnaker requires at least one man to be on deck, and the spinnaker's tack is released at the jibe from the spinnaker boom. The crew member moves the boom to the other side, and handling a spinnaker involves a far more complicated procedure than handling a gennaker. Thanks to its asymmetrical and more dynamic form, the gennaker has also gained ground in the competition field, where it is now being used with increasing diligence. Many single-type classes have gone over entirely from the spinnaker to the gennaker. These boats often have a bowsprit mounted on the stem.

Sailing a gennaker is thus relatively simple and does not require a large crew. Two persons are often entirely sufficient. The most difficult operations are setting and taking down the sail, on the one hand because the sail is large, having approximately the same area as a spinnaker, and on the other hand because it is not fixed to a stay. Developments intended to make the gennaker even easier to handle have accordingly progressed towards systems intended specifically to facilitate setting and taking down the sail. Two different methods are used today:

I . Stocking

II. Roller

Both methods have their advantages and disadvantages . I. Stocking

The stocking consists of a rectangular channel of thin sailcloth that is as long as the gennaker is tall and has a diameter of a few decimetres so that there is room for the gennaker inside. A plastic funnel is sewn in place at the bottom of the stocking. The sail is packed into the stocking and, when it is to be set, the resulting "sausage" is hauled up after the tack of the sail has been attached to the stem and the sheet has been routed back to the cockpit. The funnel is hoisted with a separate line. All that is then necessary is to sheet home to leeward. The funnel automatically moves upwards for the remaining distance when the wind fills the sail, and the stocking accompanies it upwards like a concertina. The stocking with the funnel remains in place above the sail during sailing. When the sail is to be taken down, the funnel is pulled down from the deck with a separate line, so that the sail collapses and forms a sausage which can then be taken down easily and stowed in the sail bag.

Advantages : α No restriction on the form of the sail. Spinnakers can also be taken down with the help of a stocking, α When the stocking is pulled down, the sail is entirely enclosed and cannot flap out unintentionally. Disadvantages : α Requires control lines which run up against the mast. α The stocking sits at the masthead between the sail head intake and the sail when the sail is up. This means that the sail cannot be hoisted all the way up, which can give a disturbed sail because it does not then sit at a fixed point . α The stocking, when it is hoisted/hauled, can become caught in the block for the control line, with the result that the stocking cannot be brought down over the sail and the funnel/stocking cannot be hoisted up in conjunction with setting. α Often requires one man to be present on the deck to bring the stocking down over the sail . II. Roller

A number of manufacturers of so-called gennaker rollers have been in existence for a few years. There are two types: rollers with a single line (Genoa roller of the Furlex^® type) and rollers with a continuous (endless) line. Because the sail is of the flying type and is not rolled around a profile, such as the Furlex^® Genoa roller, the number of revolutions required to roll in the sail depends to a considerable degree on the strength of the wind and how strongly you hold onto the sheet. When the sail and the roller are being handled for taking down, packing, storage and setting, it can also be difficult to maintain control over the "right number of turns" with a line on the roller. It has emerged for this reason that a continuous line is preferable, as you are then not restricted to a certain number of turns on the roller. The roller is attached between the tack of the sail and the boat. When rolling in, the leading edge of the sail is placed under tension, and all that then remains is to reel in the rolling-in line so that the sail is furled. Situated at the masthead is a swivel, which means that the halyard does not become wrapped round. Two things are necessary in order for rolling in to function correctly: 1. Some form of band is required in the leading edge with torsional stiffness such that the sail can be furled around it. Different types of band, wire, rigid rope or webbing band are used today, all of which are sewn into the leading edge of the sail. The band must also be capable of withstanding the load when the sail is placed under tension before furling, and it must be sufficiently flexible for it to be capable of being packed in a sail bag.

2. The sail must be relatively flat and must not have an excessively large shoulder. Otherwise, there will be too much

"sag" that cannot be furled in a satisfactory fashion. Point 2. above involves a compromise between furlability and sail performance. A gennaker is by definition a bulging "saggy" sail with a large shoulder, although in order to achieve acceptable furlability with today's rollers, it is necessary to reduce both the shoulder and the belly to a significant degree. These "flatter" sails then assume more of the character of a large Genoa sail for use in light winds than a gennaker. This is presumably one of the reasons why roller gennakers have not enjoyed greater success in the market .

Advantages :

Q Easy and reliable to furl from the cockpit.

□ The sail can be hoisted to the masthead, since no space is required for a stocking above the sail.

Q No control lines are required to go up into the mast to take in the sail .

Disadvantages : α Requires you to have some form of tabling in the leading edge around which to furl, which gives a more expensive sail .

D Requires the sail to be tensioned strongly in order for furling to be effective. α There is a risk of the sail flapping out unintentionally if it remains on the mast at higher wind speeds. The principal object of the present invention is thus, in the first instance, to make available an arrangement which inter alia solves the aforementioned problems in an effective and reliable fashion. The aforementioned object is achieved by means of an arrangement in accordance with the foregoing, which is characterized essentially in that the aforementioned line is attached to the sail in such a way as to draw it together vertically when the roller is rotated in one direction, in that the sail is so arranged as to be furled with the help of the aforementioned roller after drawing the sail together, and in that furling is so arranged as to be effected around a rotatable leading edge extending between the roller and the mast . The invention is described below as a preferred illustrative embodiment, in conjunction with which reference is made to the accompanying drawings, in which:

Fig. 1 shows a schematic side view of a sailing boat which has a sail with an arrangement in accordance with the present invention;

Fig. 2 shows an arrangement in accordance with the invention from a closer viewpoint;

Fig. 3 shows an exploded view of the arrangement;

Fig. 4 shows lines attached to the arrangement ,- Fig. 5 shows a perspective view of the arrangement viewed from the side;

Fig. 6 shows the arrangement with the lines connected together;

Fig. 7 shows the arrangement and its rotating upper part;

Fig. 8 shows the arrangement viewed from a slightly different angle; and

Fig. 9 shows an over-sized view of the invention in its effective sailing position. In accordance with the present invention, an aid for furling a sail comprises an arrangement 1 of the kind illustrated by way of example in the drawing in Fig. 2. Such an arrangement 1 for a sail 2, and preferably a gennaker for a sailing boat 3, which preferably exhibits asymmetrical form and is arranged in such a way as to be capable of being furled with the help of a roller 4, has the roller 4 arranged in a special way. Between the sail 2 and the roller 4 there extends a line 5, and the aforementioned roller 4 is so arranged as to be capable of being caused to rotate in the desired direction 6 and 7, in conjunction with which the line 5 is so arranged as to be rolled up on the roller 4, and the aforementioned line 5 is attached to the sail 2 in such a way as to draw it together, i.e. to gather it together in the vertical sense H when the roller is caused to rotate in one direction 6 or 7. The sail 2 is also so arranged as to be furled with the help of the aforementioned roller 4 and a further part 12 after drawing together the sail 2 in the vertical sense H so that the belly B of the sail is eliminated by having been drawn together to a straight part of the sail in question. The aforementioned furling of the sail 2 is so arranged as to be effected around a rotatable leading edge 9 arranged between the roller 4 and the mast 8. The aforementioned line, which is known as a draw line 5, is supported in such a way that it is capable of being rolled up on a line roller 4, which extends essentially vertically, and the draw line 5 is capable of being attached at the bottom in such a way as to prevent its rotation to a rotating part 12 connected to the attachment 50 for the aforementioned line roller 4 to the deck 11 of the boat 3.

The line roller 4 is mounted so that it is capable of pivoting jointly about the axis of rotation 13 of the leading edge. The rotating part 12 is formed by a part which functions as a rotating arm to which the draw line 5 is movably attached at a distance L from the central axis of rotation 14 of the aforementioned rotating arm, which is arranged essentially vertically or with a slight inclination up against the upper part 8A of the mast in a direction away from the aforementioned deck 11 of the boat. The aforementioned rotating part 12 is formed in accordance with the proposed illustrative embodiment from an upper dish- shaped roller case part, which exhibits a transverse through- opening 10 for the draw line 5. A roller 16 or some other contact device interacting with the draw line 5, intended to deflect the draw line 5 which runs between the roller 4 and the sail 2, is so arranged as to provide friction-reducing diversion of the aforementioned draw line 5 at its actual point of diversion. For example, a rounded edge in the opening 10 can function as a gentle deflection for the draw line 5.

A rotating part 18 capable of being caused to rotate by a control line 17 is attached to the aforementioned roller 4 in such a way as to enable them to be caused to rotate jointly as a unit and to rotate freely about the aforementioned axis of rotation 14.

The aforementioned control line 17 is preferably continuous, as shown by way of example in Fig. 2, although it can also be attached with its rotating part executed as a furling wheel 18, i.e. the control line 17 can be single, and not double, as in the illustrated example.

The roller 4, and with it the rotatably attached furling wheel 18, are covered at the bottom by a dish-shaped case 21, which is capable of being connected with its opening edge 22 extending around the periphery to enable it to be connected in a watertight fashion, but without being rotatably attached, to a corresponding matching opposing peripheral edge 23 of the upper case part 12, as shown in Fig. 5, for example. The roller 4 and the furling wheel 18 are formed by a jointly connected or separately rotatable part 35. The aforementioned control line 17 extends outwards with its parts 17A, 17B via a number of through-openings 24, 25 in the aforementioned roller case part 21.

The aforementioned leading edge 9 of the sail 2 is attached, in such a way as to be capable of rotating, to the upper part 8A of the mast via a pivotally mounted securing line 26 or some other rotatable bearing part, and the aforementioned leading edge is formed by a flexible, torsionally stiff band 9. The leading edge 9 is attached at the bottom 9A to the deck 11 of the boat via the aforementioned parts 4, 12, 14, 18, 21 attached to a common rotating unit 27 and a rotating attachment 50 executed as a double articulation to an anchor point 28 on the deck 11. A transverse connecting shaft 29 for the lower part

9A of the leading edge 9 is accommodated in matching holes 30, 31 in the upper half 12 of the case. A jointly connected draw line roll 4 and a control line rotating wheel 18 are thus mounted in such a way as to be free to rotate on an aforementioned pivotally mounted non-rotating shaft 14. An aforementioned rotatable common part 35 is accommodated internally in a two-part case, in conjunction with which through-openings 10, 24, 25 for the draw line 5 and for a control line 17 are arranged in the respective parts 12 and 21 of the case, and one part 12 of the case and the rotatable part 35 are attached to one another via a swivel. The draw line 5 extends as shown in Fig. 1 between the lower and upper tip parts 32, 33 of the sail and is attached to and guided by the sail 2 along its height by a number of combined attachment guides 34 on the sail.

The function of the arrangement described above is as follows :

The present arrangement 1 thus comprises a rotating roller, which differs from the existing previously disclosed sail furling rollers in that a draw line 5 is so arranged as to first draw the sail 2 together in the vertical sense H before furling of the sail 2 about an axis of rotation starts automatically.

Furling of the sail 2 starts and takes place automatically if a continuous pull is applied to the control line 17 and when the draw line 5 is extended.

In this way the gennaker sail 2, which exhibits a large shoulder and a deep belly B, is caused to assume the desired, flatter "Genoa" form before furling of the sail 2 commences . Drawing together of the sail 2 in the vertical sense H starts automatically when you take hold of the preferably manually actuated control line 17 which functions as a furling line. Only when the draw line 5 is fully extended does the actual furling of the sail 2 start by the draw line 5 interacting in its extended position with the rotatable upper part 12 of the case functioning as an arm. Furling of the sail 2 takes place by rolling around the tabling 9 of the sail .

The tabling 9 is of the same kind as referred to above, and in the present case, too, it is necessary for the sail 2 to be placed under tension before furling commences, which is effected step by step as follows: Furling .- α Take hold of the halyard so that the leading edge 9 of the sail is stretched. α Take hold of the furling line 17. The draw line 5 first draws the sail 2 together with the help of the roller 4, whereupon, when the draw line 5 is fully extended, the case part 12 begins to rotate and wind the sail around the leading edge 9. a The halyard is then released, and the sail roller and the masthead swivel and the actual roller can then be taken down as a common unit and stowed in the sail bag, etc. Thanks to its flexibility, the leading edge 9 permits the sail to be folded up. Setting : α The roller 27, which is fixed to the tack of the gennaker, is attached to the front 3A of the boat 3. α The halyard is attached to a swivel connected to the head of the sail . α The sheet and the control line 17 are then routed to the cockpit 36. α The furled sail 2 is hoisted to the masthead. □ Pull on the lee sheet to unfurl the sail 2. α Release the halyard slightly o that the sail assumes its form.

Advantage over existing rollers α The gennaker can be sewn with a large shoulder and belly thanks to the fact that the draw line 5 causes the belly of the sail to be drawn together, whereby the sail 2 can still be furled effectively. It is thus possible to furl a "real" gennaker, unlike the situation with today's rollers, which are only capable of furling heavily cut- down sails.

The invention is naturally not restricted to the embodiment described above and illustrated in the accompanying drawings. Modifications are possible, especially with regard to the nature of the different parts or through the use of equivalent technology, but without departing from the area of protection afforded to the invention as defined in the Patent Claims. For example, the roller can be in the form of an upper transverse roller component, onto which the draw line is first wound, and the aforementioned transverse roller can be actuated, once it has wound in a sufficient amount of the draw line for a rotation actuating arm attached to the line, by the aforementioned arm in such a way as to cause rotation of the aforementioned roller unit as a whole, which can exhibit the form of a cross or a T .

Claims

P a t e n t C l a i m s

1. Arrangement (1) for a sail (2) for a sailing boat

(3) which exhibits preferably asymmetrical form and is so arranged as to be capable of being furled with the help of a roller (4) , and there is a line (5) extending between the sail (2) and the roller (4), and the aforementioned roller (4) is so arranged as to be capable of being caused to rotate, in conjunction with which the line (5) is so arranged as to be wound onto the roller (4), characterized in that the aforementioned line (5) is attached to the sail (2) in such a way as to draw it together, i.e. to draw it together in the vertical sense (H) when the roller (4) is caused to rotate in one direction (6 or 7) , in that the sail (2) is so arranged as to be furled with the help of the aforementioned roller

(4) after drawing together the sail (2) , and in that the furling is so arranged as to be effected around a leading edge (9) arranged between the roller (4) and the mast (8) .

2. Arrangement in accordance with Patent Claim 1, characterized in that the draw line (5) is supported in such a way that it is capable of being rolled up on a line roller (4) , and in that the draw line is capable of being attached in such a way as to prevent its rotation to a rotating part

(12) connected to the attachment (50) for the leading edge (9) .

3. Arrangement in accordance with Patent Claim 2, characterized in that the line roller (4) is mounted so that it is capable of pivoting jointly about the axis of rotation

4. Arrangement in accordance with one or other of Patent Claims 2-3, characterized in that the rotating part (12) is formed by a rotating arm to which the draw line (5) is movably attached at a distance (L) from the central axis of rotation (14) of the aforementioned rotating arm.

5. Arrangement in accordance with Patent Claim 4, characterized in that the rotating arm (12) exhibits a transverse through-opening (10) for the draw line (5) .

6. Arrangement in accordance with one or other of Patent Claims 2-5, characterized in that the rotating part

(12) is formed from an upper roller case part.

7. Arrangement in accordance with one or other of the above Patent Claims, characterized in that a rotating part (18) attached to a control line (17) is connected to the draw line roller (4) for the draw line (5) to form a common roller (35) .

8. Arrangement in accordance with Patent Claim 7, characterized in that the aforementioned control line (17) is continuous .

9. Arrangement in accordance with one or other of

Patent Claims 7-8, characterized in that the roller (35) is covered at the bottom by a case (21), which is so arranged as to enclose the operating roller (18) .

10. Arrangement in accordance with Patent Claim 9, characterized in that the control line (17) extends outwards via a number of through-openings (24, 25) in the aforementioned roller case part (21) .

11. Arrangement in accordance with one or other of the above Patent Claims, characterized in that the leading edge (9) is rotatably attached to the upper part (8A) of the mast via a pivotally mounted securing line (26) .

12. Arrangement in accordance with one or other of the above Patent Claims, characterized in that the leading edge is formed by a flexible, torsionally stiff band (9) .

13. Arrangement in accordance with one or other of the above Patent Claims, characterized in that the draw line (5) extends between the lower and upper tip parts (32, 33) of the sail (2) and is attached to and guided by the sail (2) along its height .

14. Arrangement in accordance with Patent Claim 7, characterized in that a draw line roll (4) and a control line rotating wheel (18) are mounted in such a way as to be free to rotate on a pivotally mounted preferably non-rotating shaft (14) , in that an aforementioned rotatable part (35) is accommodated internally in a two-part case (27) , in conjunction with which through-openings (10, 24, 25) for the draw line (5) and for a control line (17) are arranged in the respective parts of the case, and in that one part (12) of the case and the rotatable part (35) are attached to one another via a swivel .

15. Arrangement in accordance with Patent Claims 7, 9 and 14, characterized in that the case (21) is so arranged as to be non-rotating relative to its shaft (14) .