AU2008316337B2

AU2008316337B2 - Rotary harness for the practice of air towed sports

Info

Publication number: AU2008316337B2
Application number: AU2008316337A
Authority: AU
Inventors: Tristan Chauvet
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-08-17
Filing date: 2008-08-04
Publication date: 2012-06-28
Anticipated expiration: 2028-08-04
Also published as: AU2008316337A1; FR2920016B1; EP2188173B1; WO2009053558A2; ES2620094T3; FR2920016A1; WO2009053558A4; EP2188173A2; WO2009053558A3

Abstract

The rotation device of the invention comprises a harness, a closed rigid rail (41), means (44, 46, 47, 48) for connecting the rail to the harness, a carriage (42) moving in or on said rail (41) on the entire length of the rail (41) in both directions and in a non-restricted manner, and a hook loop (43) attached to said carriage (42) as well as means for blocking the carriage relative to the rail. The invention can particularly be used for kitesurfing.

Description

1 A ROTARY HARNESS FOR THE PRACTICE OF A KITE-TOWED SPORT The present invention relates to a device for the practice of a kite-towed sport such as kite surfing, the device enabling the user to roll through a complete revolution without needing to disconnect from a kite to which the user is connected by a set of 5 cables. BACKGROUND OF THE INVENTION In the practice of kite surfing, the user carries a board on the feet enabling the user to slide on water, and the user is connected by a set of cables to a kite so as to be 10 able to slide on the water while being towed by the kite. In this context, the user is fitted with a device comprising a harness of textile material and attachment means fastened to the harness, the attachment means being secured to one end of a main cable that has its other end connected to the kite. In addition, two other cables connect the user to the kite, with the user 15 operating the ends of these other cables by hand via a steering bar in order to steer and direct the kite, and more generally to modulate the power of the traction delivered by the kite. The user can thus slide on the water, and take off so as to perform acrobatics in the air above the water, such as performing a roll. With a traditional device, 20 performing such a roll requires the main cable to be disconnected from the harness, a roll to be performed through one complete revolution, and then the main cable to be reconnected to the harness. This operation requires a great deal of physical strength since once the kite has been disconnected, the user must retain it solely by the strength of the arms, and this 25 operation is technical insofar as in this situation the user can no longer maneuver the kite in order to modulate its tractive power. Document FR 2 856 307 describes a device comprising a harness and a belt secured thereto and surrounding the user, the belt being in the form of a circular band. A carriage runs along that band and carries attachment means that can be 30 secured to the main cable of the kite. With that device, the user can roll through a complete revolution without disconnecting from the kite. In practice, it takes a relatively long time to master such a device and as a result it is used relatively little. 35 OBJECT OF THE INVENTION The object of the invention is to propose a solution for remedying the above mentioned drawbacks.

2 SUMMARY OF THE INVENTION To this end, in one aspect, the present invention provides a rotation device for practising kite-towed sports, the device including, a harness, a closed rail, means for securing the rail to the harness, a carriage traveling in or on the rail in both directions 5 without limit, a hook loop fastened to the carriage, wherein the hook loop is fastened to the carriage via a connection enabling it to turn relative to the carriage about an axis extending parallel to the travel direction of the carriage along the rail, the rotation device further including return means tending to return the hook loop towards a reference position relative to the carriage as soon as it is not subjected to 10 traction. In another aspect, the present invention provides a system including, a rotation device for practising kite-towed sports, the device including, a harness, a closed rail, means for securing the rail to the harness, a carriage traveling in or on the rail in both directions without limit, a hook loop fastened to the carriage, wherein the 15 hook loop is fastened to the carriage via a connection enabling it to turn relative to the carriage about an axis extending parallel to the travel direction of the carriage along the rail, the rotation device further including return means tending to return the hook loop towards a reference position relative to the carriage as soon as it is not subjected to traction, together with a fastener member including a base for securing 20 to a traction cable, said base carrying a ring and a hinged tongue, said hinged tongue being of a length longer than the diameter of the ring and extending in line with the traction cable. With this solution, the user can block the carriage relative to the rail so as to use it as a conventional device, thereby enabling the user to become progressively 25 familiarized with the roll possibilities made available by the device. SUMMARY OF OPTIONAL EMBODIMENTS OF THE INVENTION In one embodiment, the invention also provides a device as defined above, wherein the blocking means include a plunger, the rail and the carriage being 30 provided with holes suitable for receiving the plunger so as to block the carriage along the rail. M:\Graham'Clare\Speci & Amndmis\18509 Speci Rspns Andls.Docx,217/05/12, 3 In another embodiment, the invention also provides a device as defined above, wherein the plunger is carried by the carriage while being suitable for sliding relative to the carriage, and wherein the carriage includes return means for returning the plunger, tending to maintain one end of said plunger pressing against the rail. 5 In a further embodiment, the invention also provides a device as defined above, including blocking means for holding the plunger in a position where its end is spaced apart from the rail. In yet another embodiment, the invention also provides a device as defined above, wherein the rail is of section presenting at least one portion that is inclined 10 relative to an axis of symmetry of the rail. In an optional embodiment, the invention also provides a device as defined above, wherein the rail presents a section having two portions defining two bearing faces for the carriage. In a further optional embodiment, the invention also provides a device as 15 defined above, wherein the rail presents a section with at least a portion presenting a shape that corresponds to the letter T or the letter V. In yet a further embodiment, the invention also provides a device as defined above, wherein the carriage includes one or two ball bearings bearing against a bearing face of the rail, and one or two other ball bearings bearing against another 20 bearing face of the rail when a traction force is applied to the hook loop. In an embodiment, the invention also provides a device as defined above, wherein the hook loop is fastened to the carriage via a connection enabling it to turn relative to the carriage about an axis extending parallel to the travel direction of the carriage along the rail. 25 In another embodiment the invention also provides a device as defined above, including return means tending to return the hook loop towards a reference position relative to the carriage as soon as it is not subjected to traction. In a further embodiment, the invention also provides a device as defined 30 above, wherein the hook loop is secured to the carriage by two stainless steel cable portions, each cable portion having one end rigidly secured to the carriage and another end rigidly secured to the hook loop. M:\Graham\Clare\Speci & Amndmls\ 8509 Speci Rspns Amdts. Docx,317/05/12, 3A In yet another embodiment, the invention also provides a system including a device as defined above, and a fastener member including a base for securing to a traction cable, said base carrying a ring and a hinged tongue, said hinged tongue being of a length longer than the diameter of the ring and extending in line with the 5 traction cable. BRIEF DESCRIPTION OF THE FIGURES Figure 1 is a general perspective view of a first embodiment of the invention. Figure 2 is a section view showing the carriage and the rail of the first 10 embodiment of the invention. Figure 3 is a view showing a portion of the rail with the carriage in a first embodiment of the invention being shown in an exploded view. Figure 4 is a general perspective view of a second embodiment of the invention. 15 Figure 5 is a section view of the rail in the second embodiment of the invention. Figure 6 is a view showing a portion of the rail together with the carriage in the second embodiment of the invention shown in exploded view. Figure 7 is a side view of the carriage in the second embodiment of the 20 invention. Figure 8 is a section view of the carriage in the second embodiment of the invention. Figure 9 shows a first step of securing a ring to the hook loop of the device of the invention. 25 Figure 10 shows a second step of securing a ring to the hook loop of the device of the invention. Figure 1I shows the release of the ring relative to the hook loop of the device of the invention. Figure 12 is a section view of a variant section for the rail in the second 30 embodiment of the invention. Figure 13 is a section view showing another variant of the rail and of the carriage engaged on the rail. \\CI-Filesrver\Users\Graham\Clare\Speci & Anndnts\l8509 Speci Rspns Amdts.Docx,217/05/12.

4 DETAILED DESCRIPTION OF THE INVENTION The device of the invention comprises a textile harness and a closed rail for surrounding a user around the waist, and also a carriage carrying a hook loop, the carriage traveling along the rail. 5 The harness has a plurality of adjustable straps engaged in corresponding loops of the rail for the purpose of securing the rail securely to the user at the user's waist, while allowing the hook loop carried by the carriage to travel freely along the rail, all around the user. In a first embodiment of the invention as shown in Figures I to 3, the rail 10 referenced 1 is made out of a section member presenting a C-shaped cross-section. It is generally in the form of a closed circle about an axis of revolution shown AX I in Figure 1, it being equally possible for its shape to be oval or the like, and it receives a carriage referenced 2 and carrying a hook loop 3. As can be seen in Figure 2, two holes 4 and 6 are made in the front portion of 15 the rail 1, in alignment on an axis AX2 normal to the general plane of the rail I for the purpose of receiving a plunger 7. The plunger 7 serves to hold the carriage 2 at a position that is situated in the center of the front portion of the rail, when the plunger is engaged simultaneously in the holes 4 and 6 and in a central hole 8 of the carriage 2. 20 On the inside face of the rail I there is a loop 9 extending parallel to the plane of the rail, together with two loops 1 1 and 12 extending perpendicularly to the plane of the rail 1, and an inside opening 13. The loop 9 enables the rail 1 to be connected to a rear handle of the harness, with the two loops 11 and 12 being engaged by two main straps of the harness. 25 The opening 13 allows the carriage 2 to be inserted into the C-shaped cross section constituting the rail 1, and for this purpose it is of dimensions that are greater than those of the carriage 2. A plate 14 keeps the opening 13 closed, being fastened to the body of the rail 1 by four screws referenced 16 passing through the plate and screwed into four corresponding tabs 17 of the rail 1. 30 The carriage 2 comprises a main plate 18 pierced by three holes including the central hole 8 for receiving the plunger 7, and two lateral holes (not shown in the figures) that are designed to receive two pins identified by references 19 and 21. The two lateral holes are of diameters greater than the diameters of the pins 19 and 21 so as to allow the pins to pivot in these holes. 35 Each end of each pin 19, 21 is engaged in a ball bearing, the pin 19 thus carrying ball bearings 22 and 23, and the pin 21 carrying ball bearings 24 and 25.

5 One of the edge faces of the plate 18 constituting the body of the carriage 2 projects beyond the peripheral outside face of the rail 1, with two threaded rods 27, 28 being welded to said edge face of the plate for the purpose of receiving the hook loop 3 which is fastened to said threaded rods 27 and 28 by four nuts referenced 29. 5 By way of example, the hook loop 3 may be made from a straight rod or bar that is initially folded in half so as to bring its ends parallel to each other and thus constitute a loop. The end of the loop is then folded over so as to give it a hook-shape in profile. The body 31 of the hook loop constituted by the bent rod is then fastened to an 10 elongate base 32, e.g. rigidly by welding the free ends of the rod to the ends of one of the faces of the base. The base also has two holes 33 and 34 enabling it to be engaged on the threaded rods of the carriage so as to be fastened thereto. The loop body 31 may also be mounted to rotate relative to the base 34 so as to enable the loop body to pivot about an axis that is tangential to the rail when the 15 main cable of the kite is engaged relative to the plane of the rail. In operation, when the kite exerts traction on the hook loop 3, only the four ball bearings 22 to 25 are in contact with the rail via two bearing faces or running tracks formed by two inside faces of the rail 1. As mentioned above, the rail presents a C-shaped section, including, in 20 section, two rectangular portions 35 and 36 oriented parallel to the axis AXI, situated in line with each other, and spaced apart from each other by a slot in which the plate 18 of the carriage 2 is engaged. These two portions 35 and 36 have inside faces 37 and 38 constituting the bearing faces or running tracks for the ball bearings of the carriage, and they have 25 opposite ends extended by two rectangular portions 39 and 40 extending radially relative to the axis AXl, i.e. perpendicularly to the portions 35 and 36. These two radial portions have their other ends united by a portion 30 that is parallel to the axis AX1, and constitutes the web of the rail. In a second embodiment shown in Figures 4 to 8, the rail is referenced 41 and 30 is also generally circular in shape around an axis of revolution referenced AX4, but its body presents a section with at least a portion that is in the form of the letter T. The carriage, referenced 42 in the figures, has a body of U-shaped section and carries a hook loop 43, the body being suitable for surrounding a portion of the T-section of the rail. 35 As can be seen in Figure 4, the rail 41 has two loops 44 and 46 perpendicular to the plane of the rail and two loops 47 and 48 parallel to the plane of the rail. These 6 loops are spaced apart from one another by about ninety degrees around the axis AX4, e.g. being welded to the inside face of the rail body. The two perpendicular loops that are spaced apart from each other by ninety degrees constitute front loops and they are engaged in two main straps of the harness. 5 The other two loops, which constitute rear loops, are engaged in rear rings of the harness. The carriage 42 is engaged on the rail 41 and comprises a body 49 made from a generally rectangular plate that is folded to present a U-shaped section, thus defining a main portion 51 and two lateral portions 52 and 53, each of these portions being in 10 the form of a rectangular wall. The carriage 42 also carries four wheels, rollers, or ball bearings referenced 54 to 57. The first lateral portion 52 carries two wheels 54 and 55 that are situated on its inside face, and the second lateral portion 53 carries the other two wheels 56 and 57 that are also situated on its inside face. Each of the wheels 54 to 57 is engaged on one 15 end of a pin whose other end is engaged in a hole in the corresponding lateral portion, the pins and the holes being given respective references 58 to 61 and 62 to 65. By way of example, the ends of the pins 58 to 61 are crimped to the lateral portions after being engaged in the holes in these portions. Once assembled, the wheels 54 and 56 face one another and the wheels 55 and 57 also face one another. 20 When the carriage 42 is engaged on the rail 41, as shown in Figure 4, the two wheels 54 and 55 run on a first bearing face or running track of said rail, referenced 67, and the two wheels 56 and 57 run on a second bearing face or running track of the rail, referenced 68. The first and second running tracks are cylindrical inside faces of the rail 41. 25 As mentioned above, the rail 41 presents a T-shaped section, comprising a rectangular portion 50 extending radially relative to the axis AX4 and corresponding to the vertical bar of the letter T. One of the ends of this portion 50 is extended by two rectangular portions 60 and 70 that extend perpendicularly to the portion 50. These two portions 60 and 70 extend each other parallel to the axis AX4 and 30 corresponding to the horizontal bar of the letter T. The portion 50 constitutes a web stiffening the rail, and the portions 60 and 70 define the two internal bearing faces for the carriage or the running tracks 67 and 68 that are spaced apart from each other by the web 50. When the carriage is mounted on the rail, the ball bearings 56 and 57 bear against the running track 67 and the ball 35 bearings 54 and 55 bear against the running tracks 68. The carriage is also fitted with a plunger 69 carried by its main portion 51. The plunger 69 is suitable for engaging in a corresponding hole referenced 71 that 7 passes through an outside face 72 of the rail 41 and that extends along an axis AX5 that is radial relative to the axis AX4. The plunger 69 slides in a tubular part 73 that is itself engaged in a hole 74 of the main portion 51, said tubular part 73 being rigidly secured to the main portion 51. 5 The plunger 69 is fitted with a return spring 75 suitable for keeping its end pressing continuously against the outside cylindrical face 72 of the rail 41 so that said end engages in the hole 71 as soon as it comes in register therewith when the carriage 42 is moved along the rail, thereby blocking the carriage 42 in the center of the front portion of the rail 41. 10 Specifically, the return spring 75 is helical and surrounds the body of the plunger 69 while also being situated inside the tubular part 73. One of its ends presses against an inside chamfer made at the free end of the tubular part 73 and its other end presses against an outside chamfer of the body of the plunger 69 that is situated at substantially the same height as the main portion 51. 15 The free end of the plunger 69, i.e. its end that is radially furthest from the axis of revolution of the rail 41, is fitted with a plunger head referenced 76 that constitutes an abutment that presses against the end of the tubular part 73 when the plunger is engaged in the corresponding hole in the rail. Advantageously, means are provided for deactivating the plunger 69, i.e. for 20 blocking it in a position where its end is held spaced apart from the outside face 72 of the rail 41, thereby preventing it from blocking the carriage relative to the rail. These means may comprise a pin passing transversely through the plunger 69 and situated close to the plunger head 76, and two slots formed at the end of the tubular part 73, these two slots being of a length that is slightly greater than the 25 diameter of the transverse pin and being oriented along the axis of the tube 73, and being diametrically opposite about said axis. In this embodiment, in normal operation, the pin slides in the slots, thereby enabling the plunger 69 to be urged by the spring 75 against the face 72. To block the plunger in the extended position, the user pulls on the plunger and causes it to pivot, 30 e.g. through one-fourth of a turn, so that the ends of the transverse pin come to bear against the outside face of the part 73, thus blocking the plunger in the extended position. The main portion 51 of the carriage body 49 also carries the hook loop 43. The hook loop comprises a loop body 77 made from a rectangular rod or bar that is 35 initially folded in half so as to bring its ends parallel to each other and constitute a loop. The end of the loop is then folded over so as to give it a hook-shape when seen in profile.

8 Each of the two ends of the loop body 77 is crimped to a portion of stainless steel cable 78, 79. An endpiece or punch is also crimped to each of the two free ends of the stainless steel cables, these two endpieces being referenced 81 and 82. The endpieces 81 and 82 engage in complementary holes 83 and 84 provided 5 in the main portion 51 of the carriage body 49, being situated on either side of its central hole 74, and they are fastened to the main portion 51, e.g. by welding, the stainless steel cables 78 and 79 thus extending perpendicularly to said main portion 51. The stainless steel cable portions 78 and 79 serving to fasten the loop body 77 10 to the carriage are flexible, thus enabling the loop body 77 to pivot relative to the carriage body 49 about an axis parallel to the tangent to the rail 41. In addition, because of their resilience in bending, these cables tend to return the hook loop to a middle base position corresponding to the position shown in Figure 4. The hook loop 43 enables the user to make an attachment to the main cable of 15 the kite by means of a ring having a hinged tongue, as shown in Figures 9 to 11. This member serves to engage the main cable without any risk of untimely separation, while also being capable of being released reliably and quickly by acting on the hinged tongue. This member, which is referenced 91 in the figures, comprises a ring 92 that is 20 secured to the main cable 93 by a base 94. The tongue 96 is hinged in its center and is longer than the diameter of the ring 92. This tongue has one end fastened to the base 94 so as to extend in line with the main cable 93, across a diameter of the ring. In order to be secured to the cable, the user begins by engaging the hook constituted by the hook loop 3 or 43 in the ring 92, as shown in Figure 9. Thereafter, 25 the user acts by hand 97 on the hinged tongue 96 to cause it to pass inside the loop formed by the hook loop 3 or 43, as shown in Figure 10. In this situation, the hinged tongue 96 prevents the ring 92 from spontaneously escaping from the hook loop 3 or 43, thereby avoiding untimely disconnection. To disconnect from the main cable, the user presses a thumb against a central 30 region of the hinged tongue 96 so as to disengage it from the loop constituted by the hook loop 3 or 43, as shown in Figure 11. Once the tongue has been disengaged, the user is free to extract the ring 92 from the hook loop in order to release it. The invention also relates to the variants described below. In the example of Figure 5, the body of the rail 41 is made from a single T 35 section member that is supplied in rectangular shape, and that is curved using a bender. Its ends are then welded together after the carriage has been put into place, thereby constituting a T-section ring along which the carriage slides.

9 The rail may also be made from a plurality of strips or members of rectangular section that are concentric and secured to one another, as shown diagrammatically in Figure 11. Under such circumstances, the rail 41 is built up from three strips or sheets referenced 101, 102, and 103 and from a web 104, these four elements being curved 5 using a bender so as to constitute rings of complementary diameters that engage mutually. These three strips and the stiffening web may be secured to one another using radial bolts, such as the bolt fastener 106, comprising a bolt 107 passing successively through the strips 101 and 102 and then through the web 104 and the strip 103, co 10 operating with a nut 108 that is tightened onto the end of the bolt 107. Furthermore, the rail, which is shown as being of T-shaped section in Figures 5 and 12, may also present a V-shaped or Y-shaped section as in the example of Figure 13. In this example, the rail 109 defines two bearing faces or running tracks of conical shape 111 and 112 that are inclined at a right angle relative to each other 15 when seen in section. The rail 109 is then used together with a carriage 113 carrying wheels 114 and 115 rotatable about axes AX6 and AX7 that are inclined at right angles so as to enable them to run along the running tracks. Advantageously, the hook loop (not shown in Figure 13) is carried by the carriage body via a support or base 116 that is suitable for 20 pivoting relative to the carriage body. The carriage is described in both embodiments as having four wheels, ball bearings, or rollers, with two ball bearings bearing against a first running track of the rail and the other two ball bearings bearing against a second running track of the rail. The carriage may also be designed to have only three ball bearings. Starting 25 from the carriage of the second embodiment, the first two ball bearings are mounted at the ends of the first lateral portion as in the example of Figures 5 to 7 so that they both run on the first running track, while the third ball bearing is mounted at the center of the second lateral portion so as to run on the second running track. An analogous configuration for the ball bearings is also possible on the carriage of the 30 first embodiment. This solution having three ball bearings instead of four enables the carriage to bear in isostatic manner against the rail, thus making it possible to slacken manufacturing tolerances for the carriage, and thus reduce its cost. In general, the rail and the carriage of the device of the invention can be 35 fabricated by working the marine-grade stainless steel, apart from the ball bearings which are commercially available. By way of non-limiting example, the rail may have a diameter of the order of thirty-five centimeters.

10 The harness made of textile material may be a breeches buoy type harness or a back type harness. With a breeches buoy type harness, the rail secured to the harness surrounds the user around the waist. With a back type harness, the rail surrounds the user at a level situated above the waist, e.g. level with the chest. 5 The invention provides the following advantages in particular: The blocking means constituted by the plunger and the associated holes enable the carriage to be blocked in a single position relative to the rail, this reference position advantageously being situated in the center of the front portion of the rail. The user can then use the device as a conventional device, once the carriage has been 10 blocked relative to the rail. The plunger return means enable the carriage to be blocked automatically in its reference position on passing through said position, the plunger then engaging spontaneously in the rail. The possibility of holding the plunger in its extended position allows a user who has mastered the device to string acrobatics one after 15 another. The hook loop allows the user to engage reliably the main cable connecting the user to the kite without any risk of untimely separation, while also retaining the possibility of separating quickly and reliably should that be necessary. Connecting the hook loop to the carriage body via a connection that allows the 20 loop to pivot about an axis that is tangential to the rail serves to reduce the moment of the forces applied by the hook loop to the carriage, relative to the travel axis of the carriage. This reduces the risk of the carriage jamming against the rail and makes it easier to slide it along the rail in any situation. The risk of jamming may be further reduced by using a Y-type section 25 member, as shown in Figure 13, in which jamming of the carriage is impossible so long as the kite remains in an angular sector of ninety degrees defined by the normals to the running tracks 111 and 112. The fact that the wheels or ball bearings of the carriage bear against running tracks that are cylindrical or conical, i.e. that are locally plane relative to the wheels or 30 the ball bearings, improves sliding of the carriage along the rail. The structure of the rail section, which section includes portions that slope relative to the axis of symmetry of the rail, imparts considerable stiffness in bending without penalizing either its weight or its size. This rigidity reduces bending of the rail in its reference plane and contributes to improving significantly the sliding of the 35 carriage along the rail.

In general, when used under traction, only the ball bearings are in contact with the running tracks of the rail, which is rigid, thereby allowing the carriage to slide in highly fluid manner along the rail. The device of the invention is usable in the context of various kite-towed 5 sports, whether over water as in kite surfing, or over snow as in snow-kiting, or over land as with a kite mountain board, a buggy kite, or a roller kite. The reference to any prior art in this specification is not and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge. 10 Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. M:\Graham\Clare\Speci & Amndmts\18509 Speci Rspns Amdts.Docx.1 I 17/05/12.

Claims

1. A rotation device for practising kite-towed sports, the device including: a harness; 5 a closed rail; means for securing the rail to the harness; a carriage traveling in or on the rail in both directions without limit; a hook loop fastened to the carriage, wherein the hook loop is fastened to the carriage via a connection enabling 10 it to turn relative to the carriage about an axis extending parallel to the travel direction of the carriage along the rail, the rotation device further including return means tending to return the hook loop towards a reference position relative to the carriage as soon as it is not subjected to traction. 15

2. A device according to claim 1, further including blocking means for blocking the carriage relative to the rail.

3. A device according to claim 2, wherein the blocking means include a plunger, 20 the rail and the carriage being provided with holes suitable for receiving the plunger so as to block the carriage along the rail.

4. A device according to claim 3, wherein the plunger is carried by the carriage while being suitable for sliding relative to the carriage, and wherein the carriage 25 includes return means for returning the plunger, tending to maintain one end of said plunger pressing against the rail.

5. A device according to claim 4, including blocking means for holding the plunger in a position where its end is spaced apart from the rail. 30

6. A device according to claim 5, wherein the rail is of section presenting at least one portion that is inclined relative to an axis of symmetry of the rail. M\Graham\Clare\Speci & Amndmis\18509 Speci RspnsAmdts.Docx,1217/05/12. 13

7. A device according to any one of claims I to 6, wherein the rail presents a section having two portions defining two bearing faces for the carriage.

8. A device according to any one of claims I to 7, wherein the rail presents a 5 section with at least a portion presenting a shape that corresponds to the letter T or the letter V.

9. A device according to claim 7, wherein the carriage includes one or two ball bearings bearing against a bearing face of the rail, and one or two other ball bearings 10 bearing against another bearing face of the rail when a traction force is applied to the hook loop.

10. A device according to any one of claims I to 9, wherein the hook loop is secured to the carriage by two stainless steel cable portions, each cable portion 15 having one end rigidly secured to the carriage and another end rigidly secured to the hook loop.

11. A system including a device according to any one of claims 1 to 10, together with a fastener member including a base for securing to a traction cable, said base 20 carrying a ring and a hinged tongue, said hinged tongue being of a length longer than the diameter of the ring and extending in line with the traction cable.

12. A device according to claim 1, substantially as herein before described with reference to the accompanying Figures. 25

13. A system according to claim 11, substantially as herein before described with reference to the accompanying Figures. 30 M:\Graham\Clare\Spcci & Amndmts\l8509 Speci Rspns Andts.Docx.1317/05/12.