GB2478864A - Fence with fracturable connections - Google Patents

Abstract

A fence for a horse racecourse comprises an elongated front running rail 3, posts 5 disposed over the length of said running rail connected thereto via an upper connection 6, and bases 7 each adapted to be retained in the ground and offset towards rear from a position located under the running rail 3. Each base 7 includes a disconnectable lower connection 11 established between the posts 5 and said bases 7 in such a way that a disconnection between one of said posts 5 and one of said bases 7 occurs as a response to an impact F1,F3, having a horizontal component parallel to the running rail 3, carried out on the post 5. The upper connection 6 between said running rail 3 and one of said posts 5 is also adapted to break above a force threshold as a consequence of said impact. The fracturable connections are designed to protect a jockey having provoked the impact.

Description

FENCE WITH FRACTURABLE CONNECTIONS

The invention relates to a fence comprising: -an elongated front running rail, -posts, connected to it over its length, at an upper portion (called hereafter "upper connection"), -bases, each adapted to be retained in the ground.

Racecourse fences are in particular concerned.

There are fences wherein the bases are rearwardly offset towards with respect to a position -located under the running rail, a disconnectable connection being established between the posts, at a lower portion, and said bases in such a way that a disconnection between a post and its base can occurs as a response to an impact on the post having a horizontal component parallel to the running rail.

Such a racecourse fence is disclosed in AU- 200154133B2 (BORG) In terms of the problems addressed here, the following can be noted: -if the aforementioned impact occurs, it is preferable that the post provides a certain resistance, but not be too substantial in order to avoid hurting in particular a person if the latter has caused the impact, -a controlled removal of the post subjected to the impact can be useful, -said disconnectable connection (established at the lower portion) such as known in prior art of fences for racecourses does not make it possible, alone, to secure a sufficient number of configurations of impacts, -in connection with the preceding, a rotation, at the time of said impact, of the bottom of the post around the vertical axis according to which is typically erected this post in its operational state can be inappropriate in some cases.

In order to move towards a solution that takes into account at least some of such considerations, it is herein proposed that the so-called upper connection between the running rail and one of said posts at the upper portion of t1e latter be breakable (or frangible) in order to break as a consequence of the impact, above a predetermined threshold of said impact, when the post separates (or is disconnected) from its base. As a consequence, a jockey having provoked such an impact is protected, vs a racecourse fence not provided with the solution of the present invention. In conformity with the common sense, "breakable (or frangible)", or "adapted to break" means that the so-called "upper connection" is predefined for being mechanically less resistant than the surrounding structure of the fence, in the vicinity of the post upper end.

Throughout the description, the expression "...when the post is disconnected from its base..." includes that, as will probably be the case in the field, the breakage of the connection between the running rail and its post can intervene, in time, shortly after the physical disconnection between the post and its base (rather than at the time), consecutively to said impact (see further on concerning this subject) . As a first approach, the precise moment of the disconnection is therefore not absolutely decisive.

A high-performance operation will be obtained if the upper connection between the running rail and said post is adapted in order to break by twisting, following said impact exerted on this post with said horizontal impact component, parallel to the running rail.

In order to favour a controlled erasing, or collapsing, of the post, it is moreover recommended that said connection between the running rail and the post, at the upper portion of the latter, be locked in rotation by upper retaining means which connect them together and as such act against a free rotation of one in relation to the other when the post is disconnected from its base consecutively to said impact, until breaking the so-called upper connection.

According to an alternative or additional consideration of the problem, it is proposed that a connection part mechanically connected on the one hand to the post, by said upper connection and, on the other hand, to the running rail be provided, in such a way that the connection to the running rail mechanically resists when the upper connection is broken.

Typically, this connection part can belong to the aforementioned upper retaining means.

In a pertinent embodiment, it is moreover provided that the upper connection be defined by a upper pin fixing the connection between the post and the connection part, said pin being adapted to break, when the post is disconnected from its base consecutively to said impact.

More preferably, the pin shall be mounted without play (fitted) in cooperating orifices of the post and of the connection part. it is recommended that the same apply for the connection via nesting between these latter elements.

Other solutions, with controllably breakable spacer, breakable upper connection part and/or breakable upper post top, are also proposed further on.

An advantage of the solution of breakable, or frangible, pin is that the risks of aggressive debris, and even of a spring effect (solution with post top, or even with a spacer) are limited. The costs and the time for intervention for replacing are moreover then reduced. Also, the transfer of force can be favourably controlled.

Controlling all of the high and low retaining(s) of the posts under certain impacts can further improve the safety of use of the fence.

As such, is also provided, as an alternative or additional solution to the preceding that: -each post include (more preferably) a tube, -the disconnectable connection between the lower portion of said post and its base include: on an intermediate connection element wherein is engaged a lower portion of the post, lower retaining means which are upwardly solicited in response to a horizontal force applied transversally to the running rail, in the direction of the rear, and, on the base, covering means under which can be engaged the lower retaining means, in order to then be retained against said upward movement.

According to another alternative or additional consideration for this problem, it is also proposed that the disconnectable connection between the lower portion of a said post and its base include slides on the base and cooperating sliders on the post, both oriented in such a way that their disconnection intervenes as a response to said impact carried out on the post (such as Fl, F3 hereinafter) As such, a lateral escape (collapse) of the posts will occur, with more preferably an upper rupture of the aforementioned post/running rail connection, which starting with a sufficient impact (threshold) In order to perfect the so-called "lower" disconnectable post/base connection, yet another alternative or additional consideration of this problem provides that the base include a supporting plate on the ground from where are erected means carrying slides located at a distance above the plate, the disconnectable connection between the lower portion of said post and its base comprising said slides on the base and cooperating chamfered sliders on the post, in such a way that, connected to the base, the post is raised in relation to the plate.

The problem of the mechanical resistance of the posts at their base has also been considered.

That is why it is moreover recommended that each post include (at least) one tube arranged, at the lower portion, in a drum of an intermediate connection element disposed therearound (in order to reinforce it) S 6 and carries said disconnecta.ble connection between the lower portion of the post and its base.

Since a sliders/slides alone combination, in the lower portion of the posts, can in certain cases be delicate to adapt, it is also proposed, according to yet another alternative or additional consideration of the problem of the materialisation of said "lower" disconnectable post/base connection, that erasable retaining means limit at least one portion of the free sliding of the sliders in the slides, at least in one direction.

An orientation of the sliders/slides substantially parallel to the direction of elongation of the running rail, or angularly biaised from it by an angle less than 45° is therefore recommended.

It is also to be noted that hereinabove the purpose of the expression "another alternative or additional consideration" is to make it understood that the associated characteristics could each time be subject to a filing for independent protection.

According to another aspect, the invention further relates to a method for securing a racecourse fence of the type with a front running rail and posts connected through a disconnectable manner to their bases (under impact), as presented at the beginning of the

description, with as a particularity that a

predetermined threshold of said impact and as a consequence of the impact, the so-called upper connection is adapted to break when said post is disconnected from said base, as such protecting a jockey having provoked such an impact.

As a consequence, said upper connection is controllably made to break when the post separates (or is disconnected) from its base consecutively to said impact (Fl, F3) The lateral twisting that the post is subjected to subsequent to the impact can be used for this. The running rail-base disconnectable connection can consequently guide the direction of disconnection. A rather wide range of direction appears a priori possible. The description that follows presents a non-restricted example of a solution with sliders.

Concerning the running rail/post connection, it can in particular be realized by using a controlled break of a pin fitted between the post and a connection part interposed between the post and the running rail.

A more detailed description shall now be presented

in reference to the annexed accompanying drawings.

These drawings show: -in figure 1, a general view of a fence in accordance with the invention, in operational position, ready in particular to protect a horse (or other riding horse) or a jockey, by the coming apart of the post at its base in the event of an impact according in particular to Fl or F3, -in figures 2, 3, two successive steps of the lateral releasing, or collapsing, of a post are shown, following a lateral force diagramed by the arrow in figure 2, -in figure 4, details of an embodiment are shown, -in figures 5-7, several possible embodiments of the spacer 19 presented hereinafter are shown, -in figure 8, a vertical section of an embodiment of the fence is shown, -in figure 9, a vertical section of an embodiment of the base of a post is shown, -in figures 10-12, three possible embodiments of the base of a post and of a base are shown, in perspective, -in figure 13, as a horizontal section of another possible embodiment for a post bottom and a base are shown, -in figures 14, 15, an embodiment with a fracturable post top is shown, -in figures 16-19, an embodiment with a fracturable pin is shown, -in figure 20, an embodiment with a fracturable connection part is shown, -in figures 21,22 are shown two alternative embodiments, viewed from above.

In particular in figure 1, a fence 1 that can be used on a racecourse is shown.

It includes: -an elongated front running rail 3, here substantially horizontal (elongation axis 3a), -posts 5 connected to said front running rail over its length, in 6, at the upper portion, and, -bases 7 each adapted in order to be retained in the ground 9 by being offset towards the rear (AR) in relation to a position located under the running rail.

A disconnectable lower connection 11 is established between the posts, at the lower portion, and the bases 7 in such a way that a disconnection between a post and its base intervenes as a response to an impact, for example the impact Fl, applied on the post 5, horizontally and parallel to the running rail or having a partial component (Fli) oriented as such.

The so-called upper connection 6 between the running rail and a post is controllably breakable. It is provided in order to break by twisting, in liaison with the disconnection in 11 intervening between this post and its base 7, in particular consecutively to the aforementioned impact Fl. The upper connection 6 must more preferably break shortly after the disconnection in 11 has occurred. If it is, as recommended, made of plastic and bowed, the post 5 can as such exit first from its connection 11 (in particular by lateral displacement towards its base, consecutively to the impact, as detailed further on), by bending laterally (figure 2) lower than its bowing elbow 17, before the upper connection 6 then breaks (figure 3). A tubular post made of plastic (such as from PVC) must favour its lateral bending, typically at the intermediate portion of its height Hi, under the bow 17. -Regardless of the manner of carrying out the upper connection 6, the following sequence can as such occur, following an impact, or force, such as Fl exerted: -the post releases from the base (disconnection of the lower connection 11) with lateral bending of the post, twisting of the upper portion thereof, then breakage of the upper connection 6. This is shown in figures 1-3 and 18-49.

In figures 1, 2, 4, 8, note that the upper connection 6 is locked in rotation by retaining means 13 that connect post and rail together, and as such act against a free rotation of one in relation to the other, when post is disconnected from its base 7, consecutively to the aforementioned impact Fl.

In particular in figures 1, 4, 8, it can also be seen that the retaining means 13 include favourably a connection part 15 which is mechanically connected by said upper connection 6, on the one hand to the post 5 and, on the other hand, to the running rail 3 in such a way that this connection to the running rail resists when the upper connection is broken, as soon as the threshold of the force Fl or F3 is reached.

In the figures, note that the connection part 15 that connects post 5 and the running rail 3 is mechanically connected on the one hand to the upper portion of the post 5, by the upper connection 6, and, on the other hand, to the running rail 3 in such a way that this connection resists when said upper connection is broken.

Connection part 15, that can incorporate the straight protuberances 15b1, 15b2 for fixing to the running rail, by snapping in the slots 30a, 30b -see hereinafter -could also incorporate the upper connection 6, for example the mechanically weakened slots 19b1, 19b2 of the spacer 19 -see hereinafter -; the latter could pass through the thickness of its rear end piece iSa. The post 5 can then come to engage with the part 15, just behind the upper connection 6, in such a way that its breakage causes the post/running rail disconnected.

It can even be provided to incorporate together (as a single part) post 5, upper connection 6 and connection part 15: below the top end of the post carrying the incorporated means for fixation to the running rail (for example the aforementioned protuberances) would be interposed an incorporated upper breakable connection 6 (for example said slots) As such parts would be preferably made of moulded plastic (favourably via injection), it is however recommended to use: -at least two separate parts: post and part providing the functions of fixing to the running rail as well as the upper breakable connection 6, -and more preferably three separate parts: post 5, connection part 15 providing the fixation to the running rail, and part carrying the upper connection 6 and engaged on one side with the post, on the other with the connection part 15, such as the spacer 19 (or the pin 21, figure 18) For the same reasons, it is moreover recommended that each post 5 include a tube 5a. Made of plastic, the one shown is curved near its upper portion (in 17) As such, in the preferred version shown in particular in figure 8 or 18, each tube 5a is connected to the running rail 3 towards its top through the connection part 15, which will therefore be preferentially locked in rotation. Furthermore, in figure 8, tube 5a, at its upper portion, and/or the part 15 is (are) mechanically weakened in order to break consecutively to the aforementioned impact Fl.

In the solution in figures 4, 8 in particular, the upper end of the tube 5a is engaged with the spacer 19.

In order to provide its function of a fracturable junction having a certain elasticity before breakage by twisting and/or bending, it is recommended that spacer 19 be made of plastic and that it is provided with one or several mechanical weaknesses.

In figure 5, the mechanical weakening is formed by a low thickness of the wall 190 of the spacer, which is hollow (tubular, but not necessarily of circular section) . In figure 6, notches 19b1, 19b2 diametrically opposite the horizontal weakened the wall of the spacer, at the intermediate portion of its length. Figure 7 S 12 shows a connecting element including two tubular end portions connected to the intermediate portion by a rib 19b3 of reduced thickness able to be deformed elastically, by twisting and/or bending, then plastically until breakage.

In each of these cases, the upper connection will therefore include a mechanically weakened tubular spacer in order to break consecutively to the impact Fl or F3.

In any case, it is moreover recommended that the tube 5a of the post and/or the spacer 19 be engaged in the end piece 15a of the connection part protruding from the running rail, behind it.

In figures 4, 8, spacer 19 is engaged between on the one hand protruding end piece 15a and an upper end of post 5.

In order to prevent an incorrect positioning of the spacer at the time when the rupture is to occur, it is furthermore recommended that the retaining means 13 include rigid connections between on the one hand the connection part 15 and the tubular spacer, and, on the other hand, the latter and the post 5. This can entail an engagement without play each time.

In figures 1, 4, 8, the rigid connections include first and second pins 2la, 21b engaged respectively through: -the connection part 15 and the tubular spacer 19, -and the latter and the post 5.

The mechanical resistance of the pins 2la, 21b is here provided to be greater than that of the upper connection 6.

Details provided below show that this upper connection 6 can however be carried out with a breakable pin.

Figures 4, 8, but also figure 14, show a connection 23 connecting the connection part to the post in order to limit the amplitude of displacement of said post when: -it is disconnected from its base 7, consecutively to said impact Fl, -and the upper connection is broken.

Here, the connection 23 connects pins 21a, 21b.

Generally, a means, such as this connection 23, for a flexible and resistant link will make it possible to remain said post attached to the running rail 3, when this post is dismantled by the subjected impact.

In figures 14, 15 a solution is shown with a mechanically weakened post 5. There is no longer any spacer 19. Here, it is the tube 5a which is weakened.

In the example, a solution of weakening via notches, or slots, 5Obl, 50b2 is shown. In the preferred example shown, the top of post 5 is, beyond the weakened zone, engaged with the connection part 15. More preferably, such a nesting 151 is without play. A pin 21 maintains the connection between the post and the connection part 15.

As such, the post 5 has in the upper portion a upper zone 500. In figures 14, 15, it can even be seen that, closer to its free upper end, this post is connected with the connection part 15, itself connected (in l5bl, 15b2) to the running rail 3. These connections with the connection part are mechanically more resistant than the upper zone 500. In figure 15, this zone 500, located before the fitting of the pin 21, is broken under the force of twisting mentioned above.

Regardless of the version retained, the upper connection 6 shall be more solid than the lower connection 11 where the disconnection post/base will occur, at least in the case of a so-called impact angularly biased (in a horizontal plane) from an impact F2 perpendicular to the running rail, and in particular in the case of an impact Fl, or having a main component Fli. The disconnection in 11 is thus supposed to intervene before the breakage of the connection 6.

In particular in figure 4, it can be noted that the rear end piece 15a of the connection part 15 with which engages the top 50 of the post 5 is extended by a front prong 15b that is globally parallel to the elongation axis 3a. The prong 15b is attached tightened (here engaged elastically by force, through snapping) with the rear of the running rail 3. For this, the running rail has at the rear two slots, respectively top 30a and bottom 30b, disconnected from each other and extending in parallel according to the axis 3a.

They are a priori continuous. For its removable connection to the running rail, each prong l5b here has two straight protuberances l5bl, 15b2 that can be snapped into the slots. As such, the connection part 15 extends as a protrusion, behind the running rail.

Between the slots the running rail has a central groove 31 rearwardly opened, as the slots. Interiorly the running rail is partitioned into cells separated by internal partition walls, such as 33a, 33b.

It is a priori provided that the running rail, the posts 5 and the part 15 are made of rigid plastic. It is recommended that the same be applied for the other parts, excluding bases. A vinyl or polyolefin type is recommended, such as PVC or PE.

Bases 7 made partly of metal are recommended.

Concerning these bases, it is recommended that the lower connection 11 between the lower portion of a post and its base include slides 27a, 27b on the base and cooperating sliders 25a, 25b on the post.

In the assembled state of the fence, slides and sliders will typically be oriented substantially parallel to the running rail (see figures 2, 3, 8 for

example)

According to the installations, the slides of the base could however be oriented at an angle I with respect to the axis 3a which can be between 00 and +/- 450 (and even a little more), with the apex of this angle being directed towards the side from which the impact can reasonably come (for example Fl or F3, figure 1), the direction of displacement provided along the fence then being referenced as S. This direction can be that of a race taking place along the fences.

In order to favour the support and the maintaining on the ground, it can be seen on various figures that, favourably, the base 7 will include a supporting plate 70a on the ground provided with slide support means 70b, 70c.

These slides, which can be the aforementioned ones 27a, 27b, are located at a distance above the plate.

They are each formed as a "V" which can be non-truncated. A form for example in the shape of a "C" can

also be suitable.

As such, with a post provided at its base with sliders, a rising of the post will be provided with respect to plate 70a, at a position engaged with the O 16 base (distance H, figure 9 for example) . This solution must furthermore decrease the friction and therefore limit the risks of wedging.

The sliders, such as the aforementioned ones 25a, 25b, can be chamfered on the post. In the embodiment shown, the sliders are protruding and the slides are hollow. This could be the reverse.

Favourably, whether they are provided on the post or the base, the slides (27a, 27b) will preferably cooperate with the sliders (25a, 25b) according to parallel surfaces, as shown, and at least one of these slides and sliders will be made of plastic with a low coefficient of friction, such as PTFE (polytetrafluoroethylene), PE-UHPM (Ultra high molecular weight polyethylene) or POM (polyoxymethylene) . The problem of butting is as such avoided.

In order to limit at least in one direction the free sliding of the sliders in the slides, it is further noted that, in figures 1, 10, 11, 12, the connection 11 includes retaining means 29 making it possible to avoid the untimely release that can be caused by weak or parasitic forces (vibrations, oscillations of the post, effect of the wind) . More preferably, retaining means 29 will be retractable, as shown.

Such means can include one or several blade(s), such as 29a and/or 29b, arranged across from at least one side, such as 310, transverse to the sliders 25a, 25b of the post or means 31, in order to limit, or act against, a free lateral releasing of the post in 11, at least in one direction (Si figure 12) . This can be a flexible tab. It can be provided for articulating S 17 it/them to the slide support 70b/70c through a pivoting fixation, thus facilitating the setting up in both directions of the connection 11, tab raised up. When folded back, each tab becomes operational.

Also note that the lower connection 11 will favourably include, as shown, an intermediate connection element 31 wherein will be engaged a lower portion of the post (respectively of the tube 5a) and which will maintain and operationally connect post and base 7. Alternatively, the post 5 may incorporate the intermediate element 31, as a single-block portion. A realisation in two parts resolves manufacturing problems and allows each part to be optimised.

On the intermediate connection element 31 (or at the base of the post) are provided lower retaining means 33 which are upwardly solicited as a response to a horizontal force applied perpendicularly to the running rail, in a rearward direction (such as the force F2) . On the base, such means 33 cooperate with covering means 35 under which can be engaged said lower retaining means 33, in order to then be retained against said upward movement. As such, under the force according to the direction of F2, post must not disconnect from base 7 (lateral release) Means 33 and 35 can correspond to means 26/31 or 206/212-214 of WO-A-2008031150.

Figures 1, 10, 11 in particular entail respectively sliders 25a, 25b of the post and cooperating slides 27a, 27b of the base.

Concerning element 11 or the intermediate connection portion 31 supporting said lower connection 11, it is provided in figures 10, 11 that the post 5 or S 18 the tube 5a of each post be arranged, in the lower portion, inside a drum 31a of means 31.

Furthermore, in order to reinforce it, it has been provided that the intermediate connection portion 31 is downwardly enlarged in a state wherein the post 5 is connected to its base 7. In figures 9, 11, the element 31 has ribs 34. In figures 8, 10, it is provided with an outer shell 35. Such a shell and/or ribs 34 connect the drum and the slides or sliders formed thereon.

Also for reinforcing the base of post, it is recomended that post 5 or tube 5a be doubled at the lower portion by a (second) tube Sb. The two tubes will be partially received in the drum 31a and fixed together and/or to the intermediate connection element (or part) 31, by a fixation means 37. In figure 8, this is a rivet connecting these three elements together.

More preferably the two tubes 5a, 5b shall be made of rigid plastic. The length of the tube Sb above the intermediate connection portion 31 will be more preferably greater than that within the drum 3la. The total height Hi of the tube 5b will be more preferably between 1/5 and 1/3 of the height H2 of the post 5 under its elbow 17.

Further note that in the operational position of the posts, the portion of each one of them located under the elbow 17 shall be more preferably vertical, likewise, in the examples shown, than the drum 3la, the sliders as well as the slides 27a, 27b then being horizontal. In the extension of the elbow, the post becomes horizontal. Such is also the orientation of each spacer and of the connection part 15. Slanted orientations can be considered. S 19

In order to retain the base 7 in the ground 39, a stake 41 is provided, driven into the ground. It extends under the plate 70a and can be as a vertical blade. More preferably, the stake shall be made of metal, as the plate 70a. They can be welded together.

In figures 1, 10, 11, the blade or stake 41 has a "V'7 shape rearward open, with therefore a tip 41a oriented towards the running rail and here an axis of symmetry 43 perpendicular to the axis 3a of the running rail, when fence is operational. More preferably, and as shown, the opening angle c of the "V" of the blade shall be greater than 60° and even favourably 90°.

Figure 17, the blade 41 has the form of a U-shaped bracket. This shape is preferable to that of the "V" shown in figures 1, 10, 11, for improved stability within the ground.

In figure 13, a releasable snap means system 45 is shown, such as an abrupt spring latch for locking/unlocking, which prevents the post or the intermediate connection portion 31 from becoming detached untimely from the base 7, within the framework of the lower connection 11. It can entail a ball or a part with a spherical end piece, 47, pushed by biasing means 49, such as a spring, towards a notch 51 of the slider, in order to become lodged in the retaining state. Consecutively to a force on the post (impact, in figure 13), non parallel to F2, the lower connection 11 is disconnected (here the base of the post slides) after releasing of the notch 51. There can be a notch on both sides.

In figures 16-19, the post 5 is, at the upper portion, connected with the connection part 15 which is itself connected to the running rail 3 (for example clips 15b1, 15b2) . A pin 21 connects the post to the connection part. This pin is adapted to break, when the post is disconnected from its base 7 consecutively to the so-called impact, at said threshold, as can be understood with figures 18-19: Under the lateral twisting force transmitted to the top of the post, the pin breaks, here into three parts. Such breakages are here produced at the location of said orifices 50a, 150a which allow the pin to pass through the post (here tubular) and the rear end piece 15a (also tubular) of the part 15. It is recommended that the connection between the post and the connection part 15 be a nesting, or fitting, without play. The so-called retaining means 13 is accordingly defined. The rigid fixation between connection part 15 and running rail 3 (here via the clips 15b1, 15b2) also provides a contribution, favourably.

With such a solution, the upper connection 6 can be defined by the pin 21 which as such fixes the post to the connection part 15 (then without a spacer) and which is preferably fitted in the cooperating orifices 50a, 150a.

In figure 17, pin 21 is hollow. It has a central duct 210, in the direction of its length. This weakens it and favours its expected breakage. A tapered pin can be considered. With such a free of play engagement, the pin becomes well fitted in its receiving duct, favouring clean breakages, as in figure 19, by twisting.

In figure 20, the upper connection 6 is rendered breakable by a mechanical weakening of the connection part 15, located apart from part 15b provided for fixing to the running rail 3. Here notches, or slots, are formed in the rear end piece 15a, therefore around the upper end of post 5 nested therein. Beyond this upper zone, a pin 21 fixes the connection, as in figures 14, 15. For the rest, the parts are those that have already been described.

The following dimensions are provided for illustrative purposes, and are not intended to limit the scope of protection afforded by the claims. The example dimensions are suitable for all embodiments of the invention described herein: a post height of approximately 1200 mm, an overhang of the running rail of approximately 380 mm, a post tube thickness of 5 mm, for an outside diameter of the post of approximately 60 mm and a pin diameter of a magnitude of 11-12 mm ± 2mm (solid pin which can be made of PVC) Concerning the connection between the connection part 15 and the running rail 3, the snap-on protuberances 15b1, 15b2 can be supplemented or replaced with other fixation means, for example screwing means.

Concerning the so-called "sufficiency of the impact", i.e. the impact threshold, required to induce both the lower releasing (separation at the lower connection 11) and breaking of the so-called upper connection 6, tests (carried out on a fence as shown in figures 1-3 and described hereinabove) have shown that a force Fl of 30-55 daN addressed to the half lower part of the post makes it possible. Preferably, the goal is to reach roughly a deceleration of 1-2G for a mass of 50-55kg creating the so-called impact.

It is further noted that, taking into account the preceding, claims for independent protection(s) could be solicited for a set comprising, together with at least one of the following features a) to d) : a post Q 22 (5) and a base (7), the post being adapted to be connected mechanically, at an upper portion, to an elongated front running rail (3) and the base being adapted to be retained in the ground (39) and offset rearward from a position located under the running rail (3) . Preferably, a disconnectable (or releasable) lower connection (11) will be established between the post (5), at the lower portion, and said base (7) in such a way that a disconnection between the post and the base occurs in response to an impact (Fl, F3)) carried out on the post (5) and having a horizontal component parallel to the running rail.

One or several of the following additional characteristics, (a) to (d), are furthermore provided: -a) the post comprises a tube (5a) arranged, at a lower portion, in a drum (31a) of an intermediate connection element (31) that surrounds it and is provided with said disconnectable lower connection (11).

As such, solidity, lightness, reduced cost of manufacture and reliability are combined. More preferably, the tube (5a) shall be doubled at thelower portion by a second tube (5b), the two tubes being partially received in the drum and (more preferably) fixed together and/or to said intermediate connection element (31), by a fixation means (37). The resistance and the inertia will be increased. As an alternative or an addition, it is recommended that said disconnectable lower connection (11) include cooperating slides 27a, 27b) and sliders (25a, 25b) and that the intermediate connection element (31) is downwardly enlarged in a state wherein the post is connected to the base and/or has ribs (34) and/or an outer shell (35) that will then connect the drum and the slides or sliders formed thereon. A combined effect between a slight releasing, a high resistance and inertia shall as such be achieved.

-b) the disconnectable lower connection (11) includes sliders (25a, 25b) on the post and slides (27a, 27b) on the base, and retaining means (45, 47, 49, 51; 29) limit a free sliding of the sliders in the slides, at least in one direction. Increased safety will be achieved. More preferably, said means of retaining will include a releasable snap locking, possibly including a spring for abrupt locking/unlocking, a guarantee of effectiveness and reliability.

-C) the so-called slides and sliders (25a, 25b, 27a, 27b) of the lower connection 11 are oriented according to a direction that, in the plane of the ground and with respect to an axis 100 parallel to the running rail (3), defines a non-zero angle Al oriented in the direction of the running rail and which is acute facing the direction D -then imposed-for circulation along said running rail, the angle being between: more than 0° and 35-40°, and more preferably between 10° and 30°; see fig.21.

-d) the fence comprises (as illustrated in figure 22) two running rails 3, 30 disposed substantially back to back and between which are arranged the posts disposed on the so-called bases, each post 5 comprising a single upright drum 55 which, at the top, is extended by transversal sections 550a,550b connected at each free end to the respective running rails. The so-called upper connection 6 can be used, or not; the connection 58 of AU-200154133B2 (BORG) can be used, as an alternative. A bi-directional releasable through the lower connection 11 can be used, too. More preferably, the aforementioned slides and sliders (25a, 25b, 27a, 27b) will be oriented according to a median axis, such as axis 100, parallel to the two running rails (respective parallel axis 3a1,3a2).

Concerning paragraphs (c) to (d), the following can be noted, respectively: Fig.21, the fence is that in fig.l. The slides and sliders 25a, 25b, 27a, 27b of the connection 11 are oriented according to a direction 120 that, in the plane of the ground 9 and in relation to the axis 100 parallel to the running rail 3, defines therefore said angle Al oriented in the direction of the running rail.

Angle Al is acute facing the imposed racing direction D along running rail 3. The latter provides increased safety in particular for the jockey, on a racecourse, if the latter slides under the running rail, while he is moving in direction D. It is to be noted that such an acute angle Al for releasing a post in a monodirectional consideration (racecourse direction D) was already disclosed in AU-200154133B2 (BORG) Regarding the so-called slides and sliders, it is also to be noted that their rectilinearity and parallelism is not strictly compulsory; for example, sliding surfaces respectively convex and concave could be used, on both lateral sides.

In fig.22, the releasable connection solutions 6 and 11 described hereinabove and shown can be applied to a bidirectional solution: see the respective opposite racing directions Dl and D2. Two parallel, or substantially parallel, running rails, 3, 30 can each be connected trough a series of fracturable upper connections 6 to posts 510, each connected to one of said bases 7, via the aforementioned lower connection 11. Each post 5 comprises a single vertical drum 55 which, at the top, is extended by transversal sections 550a,550b, typically in the shape of a "T", or even in the shape of a "Y". In fig.21, is shown a solution with a T shape, wherein the central drum 55 is continuously extended (here in a single-unit manner) by a horizontal branch formed by both transversal sections 550a,550b.

Such a branch is connected at each free end to one of the running rails. Connections 6 can be used. The aforementioned slides and sliders (see fig.10) such as 25a,27a are oriented according to axis 100 parallel to the two running rails 3, 30. More preferably, this axis will be located at an equal distance D3 from the two running rails (median axis) and the two colinear sections 550a, 550b defining the transverse branch, on either side of the axis 100 shall be identical. (Acute) angle Al can be used, with no retaining means 29 (fig.12) or a pair of such retaining means 29 respectively disposed for operating in both releasing directions, according to the racing directions Dl and D2.

Claims (13)

1. CLA I MS1. A fence for a racecourse comprising: -an elongated front running rail (3), -posts (5) disposed over the length of said running rail and connected thereto via an upper connection (6), at an upper portion, -bases (7), each adapted to be retained in the ground (39) and offset towards rear from a position located under the running rail (3), a disconnectable lower connection (11) being established between the posts (5), at a lower portion, and said bases (7) in such a way that a disconnection between one of said posts (5) and one of said bases (7) occurs as a response to an impact (Fl, F3) having a horizontal component parallel to the running rail (3) carried out on the post (5), characterised in that said upper connection (6) between said running rail (3) and one of said posts (5) at said upper portion is, as a consequence of said impact (Fl, F3), adapted to break above a force threshold of said impact, when the post (5) is then disconnected from the base (7), in such a way as to thus protect a jockey having provoked said impact.
2. 2. A fence according to claim 1, characterised in that said upper connection (6) is locked in rotation by upper retaining means (13) that connect the running rail (3) and the post (5) together and act as such against a free rotation of one in relation to the other when the post (5) is disconnected from the base (7) consecutively to said impact (Fl, F3), until the break of the upper connection.
3. 3. A fence according to one of the preceding claims, characterised in that said upper connection (6) is adapted to break by twisting following said impact (Fl, F3) exerted on the post (5)
4. 4. A fence according to one of the preceding claims, characterised in that it comprises a connection part (15) which is mechanically connected on the one hand to the post (5) by said upper connection (6, 21, 19b1, 500, 600) and, on the other hand, to the running rail (3) in such a way that said mechanical connection to the running rail resists when the upper connection is broken.
5. 5. A fence according to one of claims 1 to 3, characterised in that an upper portion the post (5) is connected with a connection part (15) connected to the running rail (3) and a pin (21) is adapted to fix the connection between the post (5) and the connection part (15), said pin being adapted to break when the post (5) is disconnected from the base (7) as a response to said impact.
6. 6. A fence according to one of the preceding claims, characterised in that the upper connection (6) comprises, on the post (5), a mechanically weakened zone (500, 500a, 500b) formed at an upper portion of the post (5)
7. 7. A fence according to one of claims 1 to 4, characterised in that: -the upper connection (6) comprises at least one of: a tubular spacer (19) mechanically weakened in order to break consecutively to said impact (Fl, F3) and engaged between an end piece (15a) of the connection part (15) protruding from the running rail (3), behind it, and an upper end (50) of the post (5), and, a mechanical weakening formed at an upper portion of the post (5), -and rigid connections that are more mechanically resistant than the upper connection (6) are established between on the one hand the connection part (15) and the tubular spacer (19), and, on the other hand, the latter and the post (5)
8. 8. A fence according to one of claims 1 to 4, characterised in that each post (5) comprises a tube (5a) connected at the upper portion by a nesting and a pin (21, 21a, 21b) , with a connection part (15) connected to the running rail (3), in such a way that said connection to the running rail resists when the upper connection (6) is broken.
9. 9. A fence according to one of the preceding claims, characterised in that said disconnectable connection (11) comprises: -on an intermediate connection element (31) wherein is engaged a lower portion of said tube (5a) lower retaining means (33) which are upwardly solicited as a response to a horizontal force applied transversally to the running rail (3), in a rearward direction, -and, on the base, covering means (35) under which is engaged the lower retaining means (33) in order to then be retained against said upward movement.
10. 10. A fence according to one of claims 1. to 8, characterised in that each post (5) comprises a tube (5a) arranged, at a lower portion, in a drum (31a) of an intermediate connection element (31) that surrounds it and carries said disconnectable connection (11)
11. 11. A fence according to one of the preceding claims, characterised in that the disconnectable connection (11) comprises cooperating slides (27a, 27b) and sliders (25a, 25b) which are oriented in such a way that they disconnect from each other as a response to said impact (Fl, F3) carried out on the post (5)
12. 12. A fence according to one of the preceding claims, characterised in that: -the base (7) comprises a plate (70a) applied on the ground (39) and from which is erected means (70b, 70c) adapted for carrying slides (27a, 27b) at a distance above the plate (70a), and -said disconnectable connection (11) comprises said slides (27a, 27b) on the base (7) and chamfered sliders (25a, 25b) on the post (5), in such a way that, when connected to the base (7), the post (5) is raised in relation to the plate (70a)
13. 13. A fence according to one of the preceding claims, characterised in that said disconnectable connection (11) comprises slides (27a, 27b) cooperating with sliders (25a, 25b) along parallel surfaces, and at least one of the slides and sliders is made of plastic with a low coefficient of friction, such as PTFE, E-UHPM, POM. /14. A fence according to one of the preceding claims, characterised in that: -said disconnectable connection (11) comprises slides (27a, 27b) on the base (7) and cooperating sliders (25a, 25b) on the post (5), and, -retaining means (45, 47, 49, 51; 29) limit at least a portion of a free sliding of the sliders (25a, 25b) in the slides (27a, 27b), at least in one direction.15. A fence according to one of the preceding claims, characterised in that a flexible and resistant link (23) keeps the post (5) linked to the running rail, when the post is disconnected by the subjected impact.16. A fence according to anyone of the claims, 11 to 14, characterised in that said slides and sliders (25a,25b,27a,27b) of the lower connection (11) are oriented according to a direction that, in the plane of the ground and with respect to an axis (100) parallel to the running rail (3), defines a non-zero angle (Al) which is acute facing an imposed direction (D) for circulation along said running rail, said non-zero angle being less than 40°.17. A fence according to anyone of the preceding claims, comprising two running rails (3,30) disposed substantially back to back and between which are arranged said posts disposed on said bases, each post (5) comprising a single upright drum (55) which, at the top, is extended by transverse sections (550a,550b) connected at each free end to the respective running rails.18. A method for securing a racecourse fence comprising: -an elongated front running rail (3), -posts (5) disposed over the length of the running rail and connected thereto via an upper connection (6), at an upper portion, -bases (7) each adapted to be retained in the ground (39) and offset rearwardly from a position located under the running rail (3), disconnectable lower connections (11) being established between the posts (5), in the lower portion, and said bases (7) in such a way that a disconnection between one of said posts (5) and one of said bases (7) occurs in response to an impact (Fl, F3)) carried out on the post (5) and having a horizontal component parallel to the running rail (3), characterised in that above a threshold of said impact and as a consequence of the impact, said upper connection (6) is adapted to break when said post (5) is disconnected from said base (7), as such protecting a jockey having provoked such an impact.19. A method for securing a fence according to claim 18, characterised in that said upper connection (6) is broken by breaking a pin (21) set up between the post (5) and a connection part (15) interposed between the post (5) and the running, rail (3) 20. A fence constructed and arranged substantially as hereinbefore described or with reference to any one of Figures 1 to 22 of the accompanying drawings.21. An upper connection for a fence constructed and arranged substantially as hereinbefore described or with reference to any one of Figures 1 to 8 or 14 to 22 of the accompanying drawings.22. A fence post constructed and arranged substantially as hereinbefore described or with reference to any one of Figures 1 to 22 of the accompanying drawings.23. A fence base constructed and arranged substantially as hereinbefore described or with reference to any one of Figures 1 to 3, 8 to 13, 16, 21 or 22 of the accompanying drawings.24. A method for securing a fence substantially as hereinbefore described or with reference to any one of Figures 1 to 22 of the accompanying drawings.