GB2167721A - A device for reducing by winding the surface of a piece of cloth stretched between two points, notably a sail winder - Google Patents

Abstract

A device, e.g. a sail winder, for reducing the surface of a piece of cloth stretched between two fixed points, of tubular shape and supported by a cable stretched between the two fixed points and about which winds a piece of cloth when a rotary motion about its axis is imparted to it, comprises at least one modular element 10 of predetermined length. For facilitating the setting to the required length of the device once in position, at least one complementary or take-up element 11, of undefined length, is provided between one of the ends of the cable supporting the device and the modular element, and arranged so as to slide inside or outside said modular element and to occupy any required position with respect to said element. The elements 10 and 11, once the relative position they have to occupy as a function of the length of the device set in position has been established, may be fixed one onto the other by a resilient deformable connection 14 so as to accommodate differences of tension likely to be applied to the cable supporting the winder and to neutralize the shearing efforts to which said cable is subjected, caused by the motions transmitted to the platform such as a boat on which the winder is mounted. <IMAGE>

Description

SPECIFICATION A device for reducing by winding the surface of a piece of cloth stretched between two points, notably a sail winder The present invention relates to improvements to devices for reducing by winding the surface of a piece of cloth stretched between two fixed points, the device being made substantially of a tube in one or several elements, supported by a cable stretched between the two fixes points, tube on which is wound the piece of cloth when a rotary motion about its axis is imparted to it.

The invention is intended to be applicable more particularly to sail winders, but it also advantageously applicable to devices, of the type in consideration, allowing reducing the surface of pieces of cloth forming tarpaulins (for example for trucks or other vehicles), window curtains, awnings and similar.

A sail winder and more particularly a jib winder is composed, as is known and shown in Figure 1 of the accompanying drawings, of a tube A of a general circular, ovoid or elliptical shape in cross-section, provided with a drum a1 on which winds the wheel-rope (not shown) provided for the drum rotation control so that the sails winds on said drum.

In said tube extend the sail (not shown), introduced by its bolt rope in the inlet a2, and the stay b or front cable of mast c. The cable is fixed by a crimped connection at dto joining members e, e, which are respectively connected to the end of mast c and to the boat stem f. The tube is closed at its upper end by a stopper a3.

For transportation and mounting considerations, tube a which can reach considerable lengths (10 metres and more) is not made of a single piece but is constituted in the form of a plurality of modular elements, or profiles g, fitted into each other when being mounted, of a determined length, the total length of the winder being a multiple of each of said profiles.

It is indispensable for each boat or type of boat to determine the exact total length of the winder once in position and when ready to operate.

To this effect, the exact total length L (see Figure 1) of the cable (stay) supporting the winder has to be measured.

Once the length has been measured, the lengths L1 and L2 of the end and motive pieces (crimped connection d and drum a,) have to be measured and deducted from length L in order to have the precise length of the tube.

But in most cases said exact length is not a multiple integer of the lengths of the n profiles constituting the winder.

Therefore, the length of the final element (which may be used at the top or bottom of the tube) has to be adapted in order to complete said length, and this can necessitate the cutting to the required length of said element.

In short, what has to be done is a series of lengthy operations, presenting many risks of mistakes for the measurements as well as for the cutting to the required length of the winder last element.

The invention permits mounting directly the elements provided for forming the winder without it being necessary to consider the length L of the winder support cable, and therefore without it being necessary to measure it, the only condition to meet being of course that said length be less than the total length of the modular elements used for forming the winder.

The invention consists essentially in providing between the last modular element and one of the ends of the cable supporting the winder an intermediate or "take-up" element of some length, mounted telescopic-wise on said modular element so as to drive it or be driven by it in rotation, and fixed on said element by a connection which can be rigid but which is preferably resilient or deformable.

With the measures according to the invention which are adopted, the winder is set to the required length automatically without prior preparation by a simple mounting of the modular elements and of the take-up element, the assembly of which forms the winder.

The various features and advantages of the invention will become more apparent from the hereinafter description of some of its possible embodiments. It is made clear that they are given only by way of examples and that any other shapes and dispositions could be adopted without departing from the scope of the invention.

Said examples refer to an application of the invention to jib winders. On that point also, the example given is in no way limiting, and the invention can apply, as mentioned hereabove, to other winders.

For this description, reference is made to the accompanying drawings in which: Figure 2 shows schematically a jib winder made according to the invention, Figures 3 and 4 show two embodiments of the resilient connection between one modular element and a take-up element, Figure 5 is a fragmentary view, in cross-section at its upper portion and from the outside in its lower portion, of a winder with a resilient connection of the modular or take-up elements, Figure 6 is a view of the upper portion of the winder and of the fixation of its support cable to the mast, Figure 7 shows a winder according to the invention provided with a sail introduction attachment, Figure 8 shows the sail introduction attachment, and Figure 9 shows a triangular sail such as a jib in the unwound state.

As can be seen particularly in Figure 2, a sail winder according to the invention is made of two types of tubular profiles of a section of any sort: at least one and more generally a plurality of modular elements 10, of predetermined length, and an intermediate or take-up element 11, mounted at one of the ends of the winder in a manner so as to slide with respect to the modular profiles.

The telescopic mounting of said two types of profiles allows setting easily the length of the assembly forming the winder.

The section of the complementary profile 11 should be of a shape corresponding to that of profile 10 for ensuring their mutual sliding motion. Actually, one can slide on the other inside or outside.

For providing between the various elements the transmission of the rotation torque imparted to the winder in operation, it is possible to use any convenient means such as retainer keys, grooves and tongues, entraining flats, sections of non circular complementary shape, etc...

Once the winder has been set to the convenient length by mutual sliding of the profiles, their connection should be ensured once their translation motion is stopped. This connection can be rigid and provided by any convenient means, for example by screwing, rivetting, the use of a clamping separate mechanical piece such as a clamping collar or abutment.

However, it is interesting to use a resiliently deformable connection, as is shown in Figures 3 and 4, by using an element such as a sleeve or ring 12 made of a resilient material such as rubber, bearing on an abutment 13 and introduced between the two elements to be connected; or an outer spring 14 disposed between two abutments 15 and 16, one of which is fast with the modular element 10 and the other with the take-up complementary element 11.

This resiliently deformable connection is particularly interesting in the case of a jib winder. In fact, although the length of the winder is fixed, the length of the stay supporting the winder is not since the position of one the fixation points, viz.

the head of the mast, is variable, by a non negligible quantity in the longitudinal direction due to the boat motions, notably its pitching motions, with as a consequence efforts varying from a high load to a zero load, which is notably the case when the boat is braked on a wave.

In such a case, in addition to the operative clearance between the top of the winder and the lower part of the crimping portion of the cable (Lb, see Figure 1) it is very important to have as a security a variable length winder for avoiding that the crimping portion knocks on the top of the winder.

The deformable resilient connection of the profiles forming the winder allows reaching this object, as is shown in Figure 5.

Said deformable connection allows also maintaining the winder top applied directly on the crimped portion d of joining member e. In that case, the winder stopper does not bear any more on cable b but directly on the crimped portion d via a thrust bearing 17.

Breakages of the stay occur rather frequently in a position flush with the crimping portion, caused either by jamming of the yard-rope around the stay, or by the jerks caused by the pitching motion of the boat.

Indeed and as shown in Figure 6, when the stay is only slightly stretched, when the deflection that is the angle formed between the stay and the vertical, is important and when the crimped joining member is not articulated on the mast head, the cable works according to a unidirectional shearing which, repeated, can cause its breaking.

Where a deformable connection is provided, the stopper bears directly on the crimped portion and consequently the cable works under good conditions at the level of its exit from the crimped portion.

The abutment-stopper 17 is kept bearing on the crimped portion d by the resilient connection system which can therefore accommodate the length difference of the cable forming the stay.

In the non limiting example shown in Figure 7, the system consists of a spring 14 compressed between an abutment 16 and an input attachment 18 for the sail, shown at a larger scale in Figure 8. In this attachment of general cylindrical shape is formed a slot 19 in which opens a score 20 for the sail bolt rope.

The functions of said attachment are notably to protect the sail from the sharp angle edges formed when cutting the profile and to serve as a guide, that is as a score for the sail, which allows doing away with scores formed by machining, such as milling, or bending of the profile.

In the embodiments described and shown, it is the complementary or take-up element which slides inside the modular element to which it is connected. The reverse solution is however possible. But the sail such as a jib always carries cloth reinforcements 21 for the tack, as is shown in figure 9, said reinforcement once wound on the modular element forming an overthickness which is detremental for a good performance of the sail.

With the solution consisting of a complementary or take-up element sliding inside a modular element, and therefore of a diameter less than that of said modular element, the overthickness of cloth is absorbed by the difference in diameter of said two elements. There is therefore no disturbing overthickness, when winding, and the sail efficiency is not degraded.

According to the examples treated, the complementary or take-up element 11 is the lower and motive element of the winder when provided with the drum by which the winder is set in rotation. It could however form the upper end element of the winder.

In all hypothesis, the materials chosen for forming the various elements and their samplig are done so as not to cause even the beginning of a flexural rupture at the connection between the two types of elements.

Finally, one can sum up as follows the advantages of the invention, when applied notably to a sail winder: - a very simple determination of the total length of the winder by addition of the number of modular elements the length of which is known and of that, very easy to find out on the boat, of the complementary or take-up element, thereby doing away with the usual measurements and calculations and the work to be effected on a modular element for setting the winder to its final length, - the elimination of the risks of impacts between the top termination of the cable and the top portion of the winder, - the elimination of the poor angular working conditions of the cable at its exit from the crimped portion, - the provision of the sail score without having to cut, bend or deform existing grooves, - the elimination of the overthicknesses of the sail reinforcements (on the tack side) on the winder.

Of course, the invention is in no way limited to the examples described and shown, nor to its application to sail winders, notably jibs. The invention is also applicable whenever the problem is to reduce the surface of a piece of cloth, whatever its destination: tarpaulins, window curtains, awnings, etc... by means of winders having a constitution close or similar to that which is described hereabove.

Claims (8)

1. A device, notably a sail winder, for reducing the surface of a piece of cloth stretched between two fixed points, of tubular shape and supported by a cable stretched between the two fixed points and about which winds a piece of cloth when a rotary motion about its axis is imparted to it, characterized in that said device is made of at least one modular element (10) of predetermined length and, for facilitating the setting to the required length of the device once in position, of at least one complementary or take-up element (11), of undefined length, provided between one of the ends of the cable supporting the device and the modular element, arranged such as to slide inside or outside said modular element and to occupy any required position with respect to said element.

2. A device, notably a sail winder according to claim 1, wherein the complementary element (11) and the modular element (10) to which it is associated comprise means for their mutual entrainment in rotation, when the device for winding or unwinding a piece of cloth such as a sail is set in rotation.

3. A device, notably a sail winder, according to claim 1, wherein the complementary element and the modular element associated therewith, once the relative position they have to occupy as a function of the length of the device set in position has been established, are fixed one onto the other by a rigid connection.

4. A device, notably a sail winder, according to claim 1, wherein the complementary element and the modular element associated therewith, once the relative position they have to occupy as a function of trib length of the device set in position has been established, are fixed one onto the other by a resilient deformable connection so as to accommodate differences of tension likely to be applied to the cable supporting the winder and to neutralize the shearing efforts to which said cable is subjected, caused by the motions transmitted to the platform such as a boat on which the winder is mounted.

5. A device according to clairn 4, wherein the resilient deformable connection between the associated modular element and complementary element is made of a ring or sleeve (12) of a resilient material such as rubber, placed between an abutment (13) carried by the complementary element (11) and the edge of the modular element (10) inside which it slides.

6. A device according to claim 4, wherein the resilient deformable connection between the associated modular and complementary elements is formed by a spring (14) placed between abutments (15, 16) provided on the associated modular and complementary elements.

7. A device, notably a sail winder, according to any one of the preceding claims, wherein the resilient deformable connection between the associated modular and complementary elements is provided by means of an attachment (18) used as input for the sail, in which is formed a score (19) preceded by a guide (20) and through which is introduced the sail bolt rope or the slides with which it is provided.

8. A device, notably a sail winder, according to any one of the preceding claims, wherein the complementary element slides inside the modular element with which it is associated, so as to absorb the overthicknesses likely to exist on the piece of cloth, notably the overthicknesses of the jib tacks.