GB2139157A - Elongate connecting means - Google Patents

Abstract

An elongate connecting means suitable as a mooring line comprises a strong polymer cable 6 with polymer spheres 1 movable thereon, each sphere having flat end surfaces 3, the assembly being covered by the polymer cover 9. Preferably all the polymers are of density less than 1.0 so that they float. Sockets 7 and 8 are located at each end. With no tension in the centre, the sheathed assembly is flexible, and can be coiled like a mooring rope. When cable 6 is stressed to pull sockets 7 and 8 together the spheres 1 abut one another and the assembly locks as a bar thus permitting a moored or towed vessel to keep its distance from the point of attachment. <IMAGE>

Description

SPECIFICATION Elongate connecting means This invention relates to an elongate connecting means, which has both a flexible condition and a stiffened condition.

The elongate connecting means of the invention is capable of a wide variety of uses, but especially those where an interconnection between two components must sometimes be flexible and sometimes effectively rigid. By way of example, the elongate connecting means can be embodied as a boat 'tow rope", capable of being coiled (or similarly accumulated) on deck and capable of being thrown in flexible loops to shore or to another boat, but nonetheless forming an effectively rigid bar in its stiff condition.

The invention further relates to an assembled combination of such a connecting means with tensioning members which alter flexibility condi- tions, and to such a combination with an advantageous locking attachment on at least one end.

Light pleasure boats (by way of example) are provided with mooring or tow ropes, coiled or otherwise accumulated to save deck space, which for use are thrown as loose loops to shore or to another boat to be secured. The necessary flexibility for this primary use, however, renders them ineffective as "spacing" protectors e.g. against contact with the quay (or against over-running a towing vessel) with consequent paintwork or other damage. Side fenders are not always practical on small craft, and bow protection is generally non-existent.

I have discovered an elongate connecting means having in one mode adequate flexibility to perform as a rope or the like when coiled and thrown, and in another a degree of rigidity adequate as a positive "spacing" restraint. While my invention has primary utility in the field of pleasure boats it can also be used in other areas such as the towing of land vehicles, strapping and packaging, temporary accommodation (tents, marquees), builders hoist and cradle equipment, or any other environment where both flexibility and rigidity are selectively needed.

In one aspect the invention consists in an elongate connecting means comprising (a) a continuous central tension member, (b) a plurality of like units each with a straight through bore and loosely mounted around the tension member, each unit having end abutment surfaces at right angles to the straight through bore and (c) means attached to the tension member to engage an end abutment surface of one such unit; whereby tensioning the tension member pulls into abutment all of the adjacent end abutment surfaces to rigidify the connecting means, and slackening the tension member allows the abutment surfaces to part and slacken the connecting means.

The central tension member can be a wire cable but is preferably a strong polymeric cable.

The units can be cuboidal, prismatic or cylindrical but are preferably shaped generally as spheres but with diametrally opposed flat faces at right angles to a diametral through bore. Such spheres can be of any size, but from 1 to 10 cms in size is usual. The flat surface diameter will usually be from 0.5 to 1.5 times the sphere radius. Again, synthetic polymer e.g.

polyamide or polyolefin, is preferred as a material of construction.

The units e.g. spheres may be jointly covered by a generally cylindrical flexible sleeve e.g. of polymer.

A socket, matching in shape and size the end abutment surfaces, can be provided at each end of the connecting means. The assembly of the tension means, units thereon and associated sockets is an aspect of the invention.

The sockets can be formed as part of further attachment means. Thus, they can constitute the ends of cylindrical portions adapted respectively to fit over an outboard attachment eye for the cable and to bear against a winch housing the ratcheted drum of which tightens the cable. The outboard socket, in particular, may be variously adapted in dependence upon the available jetty or tow attachments, and a particularly valuable outboard attachment is shaped as the clamp member described in my Patent Application 8124589.

The invention will be further described with reference to the accompanying drawings, in which: Figure 1 is a cross-section through a generally spherical polymeric component unit of an elongate connecting member, Figure 2 is a section along ll-ll of Figure 1, Figure 3 is an end view of Figure 1, Figure 4 shows a cross-section, similar to Figure 2, of a modified component unit, Figure 5 shows diagrammatically the component parts of an elongate connecting member utilising the spherical polymeric units of Figure 1, Figure 6shows one possible complete assembly of the elongate connecting member of Figure 5, partly broken away, Figure 7shows an alternative end coupling, Figure 8 shows a further alternative end coupling, Figure 9 shows diagrammatically a boat undertow utilising a complete assembly of the general nature described in Figures 6 to 8, Figure 10 shows a number of moored boats utilising the elongate connecting members as mooring lines.

Figure 11 shows an array of "parking meters" for use with the lockable system of Figure 8, Figure 12 shows a bar having at each end a clamp member as shown in Figure 8, for attachment to the side of a vessel, Figure 13 shows the bar of Figure 12 in position, and Figure 14 shows an elongate bar for increasing the effective length of the mooring line at a jetty or quayside.

Each of the display units or "parking meters" of Figure 11 is for use with one lockable mooring line as shown in Figure 8, thus enabling the moorings operator to charge transient pleasure craft by daily, or shorter, periods appropriate to their use of the moorings. Hitherto, no "locking" arrangement has been possible, but the improved clamp and heavyduty polymer connection permits such an expedient.

It is moreover possible to provide vessels with side fittings 31 whereby bars 32 can be readily attached as needed to facilitate side fittings e.g. as at 30 (Figure 10).

Moreover, by similar extension of the concept, an end-mounted bar 33 can be attached to the jetty and receive an end fitting of the mooringline of the invention.

Figure 1,2 and 3 show a generally spherical moulded unit of polymer 1, with diametral bore 2 and flat end faces 3.

Figure 4 shows a modification of the unit, in which instead of each flat end face 3 there is provided an outer ring face 4 and inner tapered face 5.

Units as shown, according to the invention, may be assembled with a central cable 6 preferably also of polymeric material, centrally apertured end socket portions 7 and 8, shaped to match the contour of the end face 3 and adjacent surface portions, and an optional polymeric cover 9. The polymeric components can be of any wear-resistant strong material, such as for example polyamides or polyolefins and for use with pleasure boats are preferably of a density less than 1.0 e.g. polypropylene. The spheres 1, and/or the optional cover 9 may be conspicuously coloured.

When the cable 6 is slack, the spheres 1 separate to a greater or lesser extent and the assembly is flexible. When the cable is tightened, e.g. by a winch attached at the end socket8 it will draw the socket portions 7 and 8 closer together. This will progressively straighten the assembly until all adjacent faces 3 are in tight abutting relationship. In this condition, the assembly is resistant to bending or kinking, the amount of the resistance while for example less than that of a rigid metal rod, being adequate to ensure effective spacial separation of the two socket ends 7 and 8.

Having regard to the range of different detailed relative configurations possible between two adjacent spheres, and to the relative sizes of the radius R, cut-off distance D, bore B and cable gauge I believe that the detailed mathematics of the bowing or kinking relationship to the applied tension is complex, and I do not wish to be limited to any explanation or theoretical discussions. However, in simple terms, by way of example, for an assembly 1.5 m long with 30 individual spheres of 2.5 cm radius and 2.5 cm diameter end faces 3, that release of tension that allows a total of 1 cm slackness in the cable would appearto lead to a maximum possible difference of angle (as between the axes of the diametral bores 2 iin each end sphere) of about 30 tan-1 (.033/1.25) or about 45", provided that the slack is evenly distributed along the assembly.The provision of a cover 9 appears to assist this regular distribution.

This generally supports my observation that with an assembly of these proportions, tightened by a conventional winch and ratchet, there is always an available tightened position at which the assembly is acceptably rigid. The inherent slight compressibility of the polymer spheres, (and corresponding slight extensibility of the polymer cable and deformability of the polymer sockets) also assists in accommodating the tension and provising a good rigid assembly.

It is moreover possible to provide compression springs (not shown) behind the sockets 7 and 8 so as to further hold the assembly in a straight rigid condition.

Figure 6 shows the assembly of Figure 5 further elaborated with suitable end pieces to provide a separately usable article. Socket 7 constitutes part of a hollow cylinder 10, terminating in a supporting pressure plate 11. Socket 8 forms part of a hollow cylinder 12 integral with a rounded plate 13. Thus, the cable extending through socket 7 can be tied to an eye or like member as at 14 and the plate 11 thereby bear against the eye-carrying surface e.g. of a jetty or stern of a boat. Similarly, plate 12 can bear against a rounded surface of a ratcheted winch a round the drum of which is led cable 6. Thus, the whole assembly shown in Figure 6 can be used for a towline or mooring line of a pleasure boat, with no, or minimal, prior adaptation.

As a further modification, not shown, means may be incorporated for altering the effective rigid length between sockets, i.e. for altering the number of spheres. Generally, these will involve a socket which is removable and, for example, provided with a radial slotforthe cable.lfthe cylindrical portions 10 and 12 are long enough they may be used to accommodate a desired number of spheres not currently in use as part of the flexible/rigid assembly.

Alternatively, at least the outboard cylinder 10 could be apertured to allow spheres and their free supporting cable end, to protrude (if an intermediate free cable length is attached at eye 14) and thereby provide length adjustement.

Figure 7 shows a cross-section through an alternative outboard fixing necessitating a male-threaded protrusion 15 attached to the jetty, or stem of a towing boat, and a corresponding female threaded cylinder 10 with cable 6 held therein at knot 16.

Figure 8 shows a further modification of the outboard fixing, utilising a polymeric moulded clamp member of a type described in another context in my copending Application 8124589. In this, the socket 7 is formed in the end of a moulding 17 with a protruding shaft 18 of non-circular crosssection, fitting within complementary hole 19 in attachment fitting 20, itself connected byan integral ball-joint 21 to a jetty, etc. Moulding 17 and attach mentfitting 20 are held together by internal threaded sleeve 27 bearing on surrounding flange 22 of moulding 17. Cable 6 runs through the centre of shaft 17 and is fixed to its inner end. An advantage of this arrangement lies in groove 24. When sleeve 22 is fully turned into place, groove 24 is cleared and can thus accommodate a lock on a circular clip, for immobilising a boat (against all but determined attack e.g. by cutting cover 9 and the inaccessible tensioned cable 6) either at the wish of the owner or otherwise e.g for impounding a boat with overdue mooring or rental fees. Thus, a system of "parking meters" for pleasure boat mooring is rendered possible by this effective constraint on infringers.

Figure 9 shows an intended use of the assembly in towing a pleasure boat 25 by boat 26. The rigid condition of the assembly prevents overide if boat 26 slows down since the assembly acts as a spacer between the boats. However, when the assembly is detached at the outboard end 10, it is flexible enough to coil round or near the winch 27 and to throw across to the boat 26 or to a jetty.

Figure 10 shows an array of moored boats 28 wherein the bows, and the sides, are spaced with judicious use of assemblies according to the invention as at 29 and 30 respectively, against paint damage due to wash from passing boats or from the tide. Assemblies 29 can be of the "security" type discussed above in relation to Figure 8.

Although the invention has been described with reference to pleasure boating, it also has utility in camping, construction of exhibitions, the lateral ropes of painters or window-cleaners cradles, or in any environment where there is used a connecting member needing both flexibility and rigidity at different stages.

Claims (11)

1. An elongate connecting means comprising (a) a continuous central tension member, (b) a plurality of like units each with a straight through bore and loosely mounted around the tension member, each unit having end abutment surfaces at right angles to the straight through bore and (c) means attached to the tension memberto engage an end abutment surface of one such unit; whereby tensioning the tension member pulls into abutment all of the adjacent end abutment surfaces to rigidify the connecting means, and slackening the tension member allows the abutment surfaces to part and slacken the connecting means.

2. An elongate connecting means as claimed in claim 1 in which the central tensioning member is a cable of polymeric material.

3. An elongate connecting means as claimed in claim 1 or 2 in which the said units are shaped generally as spheres but with diametrally opposed flat faces at right angles to a diametrical through bore.

4. An elongate connecting means as claimed in claim 3 in which the spheres are from 1 to 10 cms diameter with a flat surface of a diameter from 0.5 to 1.5 times the sphere radius, and made of synthetic polymeric material.

5. An elongate connecting means as claimed in any one preceding claim in which the spheres are jointly covered by a generally cylindrical flexible sleeve.

6. An elongate connecting means as claimed in any one preceding claim further comprising at each end a socket member matching in shape and size the end abutment surfaces.

7. An elongate connecting means as claimed in claim 6 in which the socket at one end is formed by or located at the end of a cylindrical portion adapted to fit over an attachment eye for the cable.

8. An elongate connecting means as claimed in claim 6 in which the socket at one end is shaped at one end of a clamp member as claimed in Patent Application 8124589.

9. An elongate connecting means as claimed in claim 6 in which the socket at one end is formed by or located at the end of a cylindrical portion adapted to fit against a winch housing for tightening the cable.

10. An elongate connecting means as claimed in any one preceding claim made of a synthetic polymer of density less than 1.0.

11. An elongate connecting means as claimed in claim 1 substantially as herein described with reference to the accompanying drawings.