GB2484005A

GB2484005A - A cable security device for use in a catchpit

Info

Publication number: GB2484005A
Application number: GB1116520.6A
Authority: GB
Inventors: Stuart Edward Alan Ramella
Original assignee: Polypipe Civils Ltd
Current assignee: Polypipe Civils Ltd
Priority date: 2010-09-23
Filing date: 2011-09-23
Publication date: 2012-03-28
Anticipated expiration: 2031-09-23
Also published as: GB201116520D0; GB2484005B; GB2483894A; GB201016027D0

Abstract

A catchpit comprises an opening in a wall 34 defining a passageway for one or more cables 14 to pass into the catchpit. A cable security device for securing the cable relative to the catchpit comprises a plate 42 with an aperture, a gripping mechanism to grip the cable and a retention mechanism such as pins 18 to hold the device. The gripping means may be a collet 16, which may be in two halves and have internal teeth (56, Fig 4). The device may be larger than the opening and thus prevent theft by preventing the cable being pulled through the opening from another catchpit. A guide pin 54 may position the device on a catchpit wall. The device may also comprise two plates with resin injected between them.

Description

I

CATCHPIT

The present invention relates to a catchpit or access box/access chamber, hereinafter collectively referred to as a catchpit, a cable security device for such a catchpit, such a catchpit for receiving, or comprising, such a cable security device or two or more such catchpits featuring a cable security device in at least one of the catchpits.

Catchpits are pits or holes in the ground that are generally installed intermittently along the side of, for example, railway lines. They provide access points for accessing cables, and such like, that are located along the trackside, which cables are fed through ducting, typically lying under the ground, between adjacent catchpits or other such access points or junctions. These catchpits can also assist with drainage control, and can catch floating debris and silt.

The catchpits additionally can be for allowing water to be pumped out of the cable ducting, with the catchpits acting as sumps for the ducting, or for other cleaning, servicing or cable replacement activities along the lines.

In the past, catchpits were typically formed as a brickwork square, or as a precast concrete ring.

However, more recently they have been formed from alternative materials, such as plastics, including polythene.

Catchpits can be formed in any desired shape or size, although they are typically preformed to any one of many different standardised shapes and sizes. As such, they are typically round, square or rectangular, and they may have two or more preformed apertures/conduits in their sidewalls for connecting pipework thereto to form pipe-ducts and passageways between adjacent catchpits. Alternatively the apertures/conduits may be fitted/formed on site in or on those sidewalls, such as by drilling holes into the sidewalls.

The conduits can be of standard sizes for joining with standard sizes of pipework for forming the ducting between the adjacent catchpits.

The cables installed along the trackside, through these passageways/the ducting, are typically fairly substantial in weight, and are often made with a copper core. They can provide power distribution, or signals distribution. Such cabling can be highly valuable, even purely as scrap value, due to the weight thereof. This in turn has resulted in a growing trend for thieves to steal the cables from the trackside for sale as scrap. To do that the thieves gain access to the cables through the opening at the top of a catchpit, and they then attach a rope or a chain to the cable or cables that are accessible through that opening. They then attach the other end of that rope or chain to a vehicle and drive off with the vehicle then ripping out the cables from the passageways. Alternatively they gain access to a second, or third, etc, catchpit or chamber further down the line, where they cut the cable. They will then access the first catchpit to attach the rope as before. The thieves can thus pull long lengths of the cable from the passageways potentially between many consecutive, adjacent, catchpits from just one catchpit.

Attempts to prevent this have been made, and they include making the opening difficult to access, or simply locking the cover for the opening. However, thieves can rapidly defeat these approaches by breaking open the cover and using a longer rope. The present invention therefore seeks to provide an alternative security mechanism for deterring the theft of cables from trackside ducting through an opening in the top of a catchpit.

According to the present invention there is provided a cable security device comprising: a component with an aperture through it, the aperture being such that a cable can extend through it, a gripping mechanism for gripping that cable as it extends through that aperture; and a retention mechanism for holding or securing the cable security device relative a wall of a catchpit.

Preferably the waIl is a sidewall of the catchpit.

Preferably the retention mechanism is larger than an opening in the sidewall of the catchpit, such that the cable security device cannot pass through the opening in the sidewall of the catchpit. Preferably the cable security device has a dimension, generally perpendicular to the axis of the aperture, of no less than the corresponding dimension of the opening. The dimension may correspond to the dimension of the retention mechanism.

Preferably that dimension of the cable security device is at least 105mm wide, e.g. for a 100mm diameter ducting, or 155mm wide, e.g. for a 150mm ducting, or 230mm wide, e.g. for 225mm ducting, or 305mm wide, e.g. for 300mm ducting. Tt can also be provided, in a suitable size, for 400mm ducting, 450mm ducting, 5 00mm ducting, or other larger size ducting, e.g. by having the dimension at least 5mm larger than the ducting. It might alternatively be possible to make the dimension simply a percentile larger than the dueling. A suitable percentile might be between 2% and 10% for any of the above ducting sizes, i.e. 102mm, 153mm, etc, and since the size of the ducting will typically be known for a given application, the right size of cable security device can be pre-chosen for such applications.

Preferably the retention mechanism is adapted to be attached to the wall of the catchpit. That attachment can be permanent or removable.

Preferably the component through which the aperture is provided is of a one-piece construction.

Preferably it is a plate. The plate can be circular or square, or rectangular, or any other given shape. It could alternatively be of a two or more piece construction -it could have a block design, whereupon the aperture can be opened, and the block then closed around the cable. A housing could then hold the block in that closed configuration, by the plate being contained within a frame of the housing.

The plate can be flat on one or both sides. Alternatively it might have a side that provides a bung or plug relative to the opening -it can extend into the opening, either to locate therein, loosely or tightly, or even to seal against the inside wall thereof.

The plate can be for mounting within a housing, be it one piece or multiple pieces. Preferably that housing is provided as a part of the cable security device.

There can be multiple plates -preferably two, each to be retained within a frame.

Each plate may have one or more than one aperture through which cables may pass.

Each plate may be one piece or multiple pieces.

Preferably the or each plate takes the form of a stocks-like arrangement, with break-lines passing between the or each aperture, thereby allowing a separation of the pieces to open up each aperture, and a reassembly of the pieces to close the apertures. This facilitates retrofitting to existing cable-runs.

The frame may be a multiple piece frame, and it might have two or more pieces that are attached together in use, such as with bolts or screws.

The frame, or the pieces of the frame may envelop the or each plate for holding the plate or plates in a fixed condition relative to the frame.

The frames may have grooves or protrusions for engaging edges of the plate or plates.

The frame and two or more plates may define an internal space across which the cables will bridge when extending through the apertures.

The internal space may be adapted to receive an adhesive or resin therein, the adhesive or resin forming the gripping mechanism by it bonding onto the cable or cables, thereby providing a mechanism for retaining the cable relative to the cable security device.

The cable security device may take the form of a pair of shells, or a collection of parts, which together can surround a cable or a plurality of cables, the shells or parts collectively defining an internal space in which the gripping mechanism can be located or housed. The shells or parts form the retention mechanism.

A port may be provided on the retention mechanism, or on a frame therefor, for injecting an adhesive or resin into the retention mechanism or frame for setting against the cable or cables extending through the cable securtity device, thereby providing the gripping mechanism. The port may have a valve in it for one-way injection of the adhesive or resin.

The retention mechanism is preferably adapted to secure or hold the housing and the plate relative to the wall of the catchpit. This can be achieved by hanging it onto a hook, or by screwing or bolting it to the wall, or by gluing or welding it onto the wall.

One solution would be to make size of the apertures such that the injected adhesive (for providing the gripping mechanism) can leak through them and out to the outside of the cables and thus providing leaked glue or resin that will allow the cable security device/retention mechanism to be glued/adhered to the wall using the overflowed adhesive or resin. A 1-5mm diametrical excess would be adequate for that purpose.

Preferably the gripping mechanism is a collet. Preferably the collet is formed as a two-part collet. Preferably it comprises two generally hemi-cylindrical members. It could alternatively be a one-piece collet, or a multi-component collet.

The gripping mechanism in use may comprise a compressed rubber component.

Preferably the collet comprises a head for limiting the degree of movement of the collet through the aperture. Preferably the head of the collet is larger than the aperture. Preferably the collet and the aperture are both generally circular, whereupon the diameter of the head of the collet is larger than the diameter of the aperture.

Preferably the gripping mechanism features gripping teeth on an internal surface thereof for biting into the sheath of the cable.

Multiple gripping mechanisms, and multiple apertures, may be provided in the cable security device for separately securing more than one cable. However, a single gripping mechanismlaperture combination can be provided to secure multiple cables, all bundled together, perhaps within a sheath, like in a multi-core cable, or instead, perhaps in an array -a linear array where the cables run parallel to one another, in a side-by-side arrangement, or in a block-array, with cables stacking above and to the sides of one another.

In place of a collet, the gripping mechanism may consist of a stop, which stop may be screwed, clamped or bolted onto the cable, or the bundle/array of cables. The stop can then be for abutting against the component, thereby resisting movements of the cables relative to the component in a similar maimer to a collet.

The present invention also provides one or more cable secured by a cable security device as described above. Preferably the or each cable has a minimal external diameter of 15mm, or preferably 20mm or most preferably 25mm. The cable can even have a minimal external dimension of 30mm or 50mm.

The cable can be an armoured cable, a multi core cable or a single core cable.

The gripping mechanism is provided with a cable passageway that is appropriately sized for receiving such a cable, or such cables.

Preferably the retention mechanism comprises one or more mountings for flexibly mounting the cable security device relative to the wail of the catchpit. Preferably they are legs or pins, and preferably the component with the aperture is not fixed relative to those legs or pins. This allows the cable to be fitted within the cable security device without it necessarily being arranged to extend through the wall of the catchpit in a perpendicular fashion, i.e. not necessarily perpendicular to the wall of the catchpit. It also then does not need to be parallel to the axis of the pipe-ducting extending between adjacent catchpits (or parallel to the axis of the conduit that extends away from the wall of the catchpit towards that pipe-ducting).

Preferably the retention mechanism comprises a housing, a plate and at least one connecting leg for fixing to, or bearing against, the wall of the catchpit. The plate can be the component described above, and likewise the housing can be the housing described above.

Preferably the plate is mountable into a frame of the housing. Preferably both the plate and the frame are generally square, or generally round or generally rectangular.

Preferably there is more than one connecting leg.

The legs can be for wall mounting, or simply to bear against the wall. A combination of legs or pins, of fixed and non fixed nature can be used to provide a part-fixed mounting of the cable security device relative to the frame, i.e. providing an axis of fixation. The connecting leg might alternatively be more than one wall-mounting pins).

Preferably the plate has one or more holes through it, each sized to fit the shaft of one of the legs.

The legs can be longer than the thickness of the plate. That then allows the plate to slide along the legs, and by sliding them along each leg to a different amount, the plate can be made to tilt, thereby giving the plate a degree of flexibility relative to the wall of the catchpit.

In a variant, the legs can be made to be flexible (or the holes in the plate can be made larger than the size of the shaft of the legs). The plate can then skew even further relative to the wall of the catchpit. It is preferred, however, that the legs are stiff Preferably the legs are longer than the depth of the housing, e.g. as well as being longer than the thickness of the plate.

Preferably there are four legs, and preferably those four legs extend through four holes in the plate. Preferably the aperture is in the centre of that plate, with the four holes being at the edges of, or in the corners of, that plate. One potential benefit of four legs, where the plate is not fixed relative to the legs, is being able to introduce an angle into the assembly. The reason for this being desirable is that the cables may want to be being brought up, or angled, towards the surface or top of the catchpit, and thus the cables can be provided with a finite, but restricted, bend radius, accommodatable due to the flexibility of the four-leg/plate design -the plate can be angled relative to the four legs, to a limited degree. Different numbers of legs, with a moveable plate, could also replicate such a flexibility to a varying degree, i.e. potentially in different angular directions. The four leg arrangement, however, is highly suitable for angling the plate upwards or sideways, when the legs are arranged in two vertically spaced, arrayed, pairs.

Instead of legs, potentially there could be another form of angular adjustment for the plate, such as a ring or peg that is screwed out on a thread selectively to jack the assembly/plate away from the wall of the catchpit.

Preferably the cable is extending through the plate, with the plate being mounted within the housing, or within a frame of the housing, with a collet within the aperture surrounding the cable.

Preferably the legs have heads that are larger than the holes in the plate. The heads are on the ends of the shafts of the legs. The heads can thus limit the degree of movement of the plate along the legs.

The heads can be integral with the shafts, or can be removable therefrom.

To facilitate assembly, the legs can be glued or welded, or otherwise bonded, onto the shaft after the plate has been inserted thereon.

Preferably the retention mechanism is attached to or mounted relative to a wall of a catchpit. For example, the legs can be attached to, or can rest against, the wall of the catchpit, or a hooking point can be provided for hooking the cable security device onto the wall of the catchpit, with the legs then supporting the cable security device relative to the wall of the catchpit upon a pulling force being applied to the cable from outside of the catchpit (such as at a neighbouring catchpit).

The present invention also provides a catchpit comprising an opening in a wall thereof for defining a passageway for one or more cables to pass into the catchpit from outside of the catchpit (such as from a passageway/ducting leading from an adjacent catchpit) and a cable security device as defined above. The opening is preferably in a sidewall of the catchpit.

The catchpit may be formed with components of the cable security device integrated onto, or integral with, the catchpit. For example, the plate may be integrated over the opening, or the retention mechanism may be integral with the wall of the catchpit.

Alternatively, or additionally, the catchpit can include a hooking point onto which the cable security device, or remaining parts thereof, can be mounted via a feature of the cable security device's retention mechanism, such as a hanging eye. That hooking point can comprise a guide pin, a hook or some other hooking/hanging member, with the cable security device then comprising an eye, a hook or some other corresponding hooking/hanging member for interacting therewith, e.g. for hooking over the guide pin, the hook or the hooking/hanging member.

The cable security device is preferably mounted on or relative to a wall of the catchpit.

Preferably that mounting of the cable security device places the cable security device over the opening, on the inside of the opening. In another embodiment it might be mounted on the outside of the opening.

By having the cable security device larger than the opening, that cable security device cannot be pulled through the opening.

Preferably the catchpit is square or rectangular. The catchpit could, however, be round, i.e. generally cylindrical.

Preferably the catchpit has more than one opening, thus defining more than one passageway for cables. Two openings might face one another, i.e. they might be on opposite sides of the catchpit to one another. Such openings might define a common passageway between them.

A cable security device might be provided for each opening, or for each passageway.

The openings are preferably provided as opposing pairs, such that there are opposed openings.

A cable security device might then be provided for just one of the two openings in the pair, although preferably they are provided for every opening.

Preferably the catchpit comprises a lid or a cover or a hatch. Preferably the lid, the cover or the hatch is adapted to be lockable over the top of the catcbpit for preventing or discouraging unauthorised access into the catchpit. It might however just be screwed or bolted down, or held down by a latch.

Preferably the catchpit is modular. For example, it can be adapted to be formed of a primary body and one or more extension components, the extension component(s) allowing the height and/or depth of the catchpit to be adapted as appropriate for the location or type of installation.

For example, multiple extensions above the primary body can extend the height of the catchpit, whereas extensions below the primary body can lower the depth of the catchpit, both without changing the position of the primary body -useful since preferably the opening or openings are provided in the primary body. The openings instead, or additionally, however, might be provided in the extensions, thereby allowing passageways at different heights to be accommodated. These features can also provide a further aspect of the present invention. Such a catchpit might be provided with a hanging pin or hanging hook at a top edge of the opening.

The catchpit is then suitable for accepting a cable security device as described above for securing a cable extending therethrough. Prior art catchpits would not have such a hanging pin or hanging hook.

The catchpit may comprise a base member. That base member can be for providing a sealed bottom for the catchpit. The catchpit thus can operate as a sump for the passageways from which any retained mud or water can be removed. For example, groundwater or rainwater might otherwise collect within the catchpits/passageways such as to flood them.

In a modification of the cable security device illustrated, the cable security device may be formed on site, thereby comprising a plate and one or more gripping mechanism for gripping a cable, the plate being drilled on site to form an aperture therein of a required diameter to suit the cable to be fined therethrough.

Where the griping member is a collet, a selection of collets is provided, with the appropriately sized collet then being used over the cable, and within the aperture. The present invention can thus be a kit of parts including a plurality of different sized collets, such that a variety of differently sized holes, and thus different diameters of cables (or different numbers of cables), can readily be accommodated..

Preferably, the gripping mechanism has teeth that are directed such that they grip the cable when that cable is exposed to a pull in a likely direction of extraction, such as out of the opening in the wall of the catchpit, or optionally through the top of the catchpit.

Where the gripping mechanism is a collet, the collet is provided with a head, the head of the collet being adapted to bear against a face of the component in which the aperture is formed, i.e. typically the plate. Preferably the teeth lean towards the head of the collet.

Preferably the collet has a tapered body extending in a reducing manner from the head. The taper is designed so that attempts to pull the collet into the aperture (which usually has cylindrical walls) will tighten the grip of the collet against the cable. Ultimately the head will end up bearing against the face of the component in which the aperture is formed, thus preventing an extraction thereof through the aperture.

in an alternative embodiment, the collet may be tapered in the reverse direction such that attempts to remove the collet from the aperture in the other direction -pulling the head away from the component -will cause the collet to grip against the cable. The teeth might then also be reversed.

In a further embodiment, the aperture may itself be tapered to achieve either of these collet-tightening effects.

Iii preferred arrangements, the teeth in the col let are designed to bite into the cable's sheath, and possibly into the armour of the cable, where the cable is an armoured cable, thus gripping the cable so hard and so strongly that it cannot be removed from the catchpit without snapping the cable (or some other element of the arrangement, such as the cable security device, the retention mechanism or the catchpit).

The present invention also provides a pair of catchpits, separated by a length of ducting, with a cable extending between the two catchpits through the ducting, wherein at least one of the catchpits features a cable security device as defined above in engagement with the cable extending therethrough. With this arrangement, upon pulling a cable via an opening of one of the catchpits, the gripping mechanism wilt grip the cable, and thus resist the removal of that cable from the catchpitiducting.

The cable security device can be located either at the catchpit at which the cable is pulled or at the other catchpit, depending upon the form, and thus the direction of pull-resistance, for the gripping mechanism.

For example, a gripping mechanism arranged to grip a cable when it is being pulled in a direction such as out through the wall of its catchpit could prevent cable thefts via the other catchpit, whereas a gripping mechanism arranged to grip the cable as it is pulled in the other direction would resist attempts to steal the cable out through the top of the catchpit at which the gripping mechanism is located. The cable security device might then also be mounted on the outside wall of the catcbpit, to further enhance the cable's security.

The present invention therefore provides a robust and flexible solution to the problems surrounding cable theft through catchpits. Specifically, with the cable security device, it makes it much harder for thieves to pull cables from catchpits, or even from neighbouring eatehpits.

It will also be observed that the presence of the cable security device(s) over the openings in the walls of the catchpits prevents access through those openings to the lengths of the cable that extends between the catchpits.

Further, the cable security devices, and the catchpits, are easy to install.

These and other features of the present invention will now be described in greater detail, but purely by way of example, with reference to the accompanying drawings in which: Fig. 1 is a perspective illustration of a catchpit comprising a cable security device therein. The walls are shown in phantom to allow elements within the catchpit to be seen; Fig. 2 is an exploded reverse-perspective view of the catchpit of Figure 1; Figure 3 is a perspective view of an assembled cable security device as shown in Figures 1 and 2; Figure 4 is an exploded view of the cable security device of Figure 3; Figure 5 is a detailed perspective view of the cable security device of Figure 3, shown in a condition of use, i.e. securing a cable therethrough; Figure 6 is an exploded view of an alternative form of cable security device; Figure 7 is an assembled view of the device of Figure 6, fitted onto a set of cables; Figure 8 is a front elevational view of the device of Figure 7; and Figure 9 is a section through the device of Figure 8, fitted onto a wall of a catchpit.

Referring first of all to Figure 1, there is shown a catchpit 26 having a generally rectangular box-like shape. The catcbpit 26 has a cable 14 extending therethrough and a cable security device 10 mounted onto that cable and to the inside of a wall of that catchpit 26.

The wall 34 has an opening in it extending to a conduit 24. The conduit 24, in use, would be connected to duct runs -pipes -that extend between adjacent catchpits 26. Only a single catchpit is shown. However, such arrangements for catchpits 26, but without cable security devices, are well known in the art. The cable security device is thus the primary development over known catchpits 26.

Referring next to Fig. 2, the same catchpit 26 is again shown, this time from a reverse angle.

The rectangular shape can again clearly be seen. The walls of the catchpit can be seen, however to be dual skinned, with structural spacing bars extending between the skins. See, in particular, Fig. 5 for a more detailed section. This dual skin arrangement provides a lighter construction, but without a significant compromise in strength.

In Fig. 2, the cable 14 and the cable security device 10 are shown outside of the catchpit 26 for clarity only, the figure being an exploded view. In use, they will be inside the catchpit 26, as per Fig. 5.

The catchpit 26 comprises a primary body 36 and extensions 30. There is one extension above the primary body 36 and another below the primary body 36. The catchpit 26 also has a base 32 and a lid or cover 38.

The primary body features two conduits extending from is side walls 34 -the two conduits oppose one another so that the cable can extend through the catcbpit 26 through the two conduits.

As illustrated, the various members of the catchpit 26 are connected together with a plurality of screws/nuts/bolts 40. This allows them easily to be assembled on site for modular assembly. lit particular, additional or fewer extensions 30 can be provided as appropriate depending upon the required height or depth of the catchpit 26 relative to the primary body, and its conduits 24.

Those conduits 24, after all, define the passageways 28 through which cables will be run along the track side (through the ducting extending therebetween -not shown), and those passageways are preferably kept straight or level (albeit with a suitable fall to enable water to flow in the desired direction) to assist with drainage, whereby their height relative to a neighbouring catchpit can be important.

Additional conduits can also be provided, where needed, by using a different primary body, or by having extensions with conduits therein.

Referring next to Figures 3 and 4, details of a preferred embodiment of a cable security device 10 are provided. As can be seen, that cable security device 10 comprises a housing 22 and a plate 42 thsough which an aperture 12 is provided. That aperture 12 is for extending a cable therethrough, and the plate 42 is sized to fit within a frame 64 of the housing 22. The frame 64 is square, and the plate 42 is also square. Other shapes/arrangements are also possible. For example, there can be more then one hole drilled into the plate 42, or the plate may have rounded corners. There is thus flexibility in the design, which allows holes to be drilled as needed, such as to suit the collet / cable size or the number of collets I cables presented. The plate can even be a split plate, i.e. provided in more than one part, with the aperture being formed across the two or more parts. This further increases the flexibility of the design since it can then be retrofitted to existing cable installations.

A gripping mechanism in the form of a collet 16 is also provided and in use it surrounds that cable (as shown in Figure 5) so as to grip the cable 14 within the aperture 12. That figure also shows the cable security device's location, in use, relative to the conduit 24 in the wall 34 of the catchpit 26 The plate 42 and the housing 22 are arranged to be attached to or mounted relative to the inside surface of the wall 34 of the catchpit 26 with a plurality of pins or legs 18, each having a predetermined length, a narrowed shaft 44, an enlarged head 46 and a supporting base 48 bearing against that wall. Those legs 18 are extended through aligned holes in the plate 42 and the frame 64 of the housing 22.

For the attachment to, or the engagement with, the wall 34, the base 48 of each pin or leg 18 engages against the wall 34. This may be a simple resting of those legs against the wall, or they may be more permanently mounted thereon (such as by screws or bolts) so as to provide a predetermined fixing location for the cable security device 10. A guide hole 52 and guide pin 54, however, are more preferably used to locate the cable security device 10 in a location over the conduit 24.

The shaft 44 of the legs 18, or the head 46 of the legs, may be removable from the base, or the shaft, respectively, so as to allow the housing and plate to be fined to the legs, although any joint then made in reassembling the legs 18 might then later be made permanent, such as with adhesive or welding.

The size of the cable security device 10 is preferably larger, in at least its width or height, than the conduit 24 so as to resist any attempt to pull the cable security device 10 out through the conduit 24, i.e. through the corresponding passageway 28 into the ducting (not shown) that leads to the neighbouring catchpit (not shown). In that regard, one aspect of the invention is simply making the cable security device larger than the conduit, such that the size of the device provides a retention mechanism therefor.

hi this illustrated embodiment, the legs 18 have a narrowed shaft 44 relative to both the head 46 and the base 48 of the legs 18. That shaft 44, however, is sized to fit through the holes 50 in the plate 421 and the frame 64. In use they therefore extend through the holes 50. Those holes 50 are provided in the corners of the housing 22 and the plate 42, with the aperture 12 being in the centre of the plate 42. The holes 50 are thus spaced around the cable. This, in use, assists with the centralisation of the cable with respect to the conduit 24. Other arrangements can also, or instead, be used, however, as mentioned above, such as pegs or rings for jacking the plate or assembly away from the wall, instead of fixed legs.

Also, the holes are not tightly mounted over the shafts 44 of the legs 18. Further, the legs 18 are longer than the thickness of the plate 42/frame 64 of the housing 22. As a result, the plate 42 can slide along the shafts 44 of the legs 18, thereby allowing a degree of flexibility for the angular orientation of the plate 42 relative to the wall 34 of the primary body 36 of the catchpit 26 if the cable is flexed.

As also shown in Fig. 4, the housing 22 also has a guide hole 52. As briefly mentioned above, it is for pairing up to a guide pin 54 that is provided on the wall 34 of the primary body 36 of the catchpit 26. That guide pin 54 and guide hole 52 can be of a larger diameter than the shaft 44 of the pins 18. The guide pin/hole combination provides a point of attachment for the cable security device 10 to the catchpit, at a fixed location above the conduit. The legs can then just rest against the wall 34 of the catchpit 26, rather than being joined thereto, with that guide pin 54 and guide hole 52 providing, simply, a hanging point for the cable security device 10. The cable security device 10 will efficiently resist cable extractions from a neighbouring catchpit 26, despite a non-locked attachment to the wall of the catchpit, due to the cable security device being larger than the conduit 24.

The legs are preferably made to be substantially stiff. For example, they could be steel legs. It is possible, however, to make the legs offer a degree of flexibility themselves by having their shafts made to be flexible.

The guide pin is preferably stiff to maintain a good strength of attachment.

The attachment in the fixed location, albeit with a degree of flexibility of movement, rather than just using a free-floating cable security device, ensures a degree of centralisation for the cable relative to the conduit 24. This prevents the cable from wearing/pulling against the side of the conduit 24.

Fig. 4 also shows a preferred embodiment of collet. As can be seen, that collet 16 is provided in two parts -two hem i-cylindrical members. However, a variety of different potential collets can be provided instead, including bifurcated, trifurcated or quadfurcated collets, or other such collets of a one-piece formation.

The collets 16 serve to grip the sheath of the cable 14. For that purpose it is shown in this embodiment to have engagement teeth 56 on an inside surface thereof Other gripping mechanisms can also be adopted, as would be known to an expert in collet design.

In this illustrated embodiment, those engagement teeth 56 are angled towards a head 60 of the collet 16. This is so that they grip a cable 14 upon any attempt to pull the cable 14 out of the primary body 36 of the catchpit 26 through the ducting extending therefrom (i.e. directly out of the conduit, rather into the catchpit and then out of the top, or out through an opposing conduit).

The two parts of the collet 16 are tapered such that they narrow towards the free end of the body of the collet 16. This is so that pulling forces out through the associated conduit 24, as shown by arrow 58 in Figure 5, will cause the collet to tighten as it is drawn f3⁄4irther into the aperture 12 (to the point shown in Figure 5 -with its head 60 bearing against the plate 42). The collet is thus self-tightening in response to a pulling force in the direction shown by that arrow 58.

The head 60 of the collet 16 has a larger diameter than the aperture 12, and also of the tapering body of the collet 16. This is so that the collet 16 cannot pass through the aperture 12 in the plate 42.

With this arrangement, as explained above, attempts to pull out the cable by accessing it at an adjacent catchpit 26 will be resisted since the cable security device of a neighbouring catchpit will serve to grip the cable, thus preventing an extraction of the cable from the trackside -the cable will instead either just resist the extraction, or it will stretch or snap, the location of the stretching or snapping being limited to the length between that neighbouring catchpit (i.e. the cable security device thereat) and the point of attachment of the rope/chain that is pulling the cable. However, without the present invention, the cable would extract by snapping at a point of connection between two lengths of cable, which point of connection could be many catchpits along the line.

It is also to be appreciated, however, that the gripping mechanism's gripping direction could also be reversed, or complemented with a secondary gripping mechanism acting in the other direction, such as via a second collet, or some other supplementary gripping mechanism/cable security device, perhaps with its housing and plate on the outside of the catchpit, whereupon that supplementary cable security device could then grip the cable 14 upon pulling the cable in that other direction, such as directly out of the top of the catchpit in question. Such an arrangement, however, might be less secure than the one that grips at an adjacent catchpit since the person gaining the access to a particular catchpit could theoretically access the cable security device thereat and disable or dismantle it. It is thus preferred that the cable security device 10 serves at least to grip the cable as it exits the catchpit through the conduits/passageways in the sidewall 34 of the catchpit 26, rather than necessarily as it exits through the opening at the top of the catchpit in question.

In summary, therefore, the present invention provides a catchpit 26 comprising an opening 28 in a wall 34 thereof for defining a passageway for one or more cables 14 to pass into the catchpit 26 from outside of the catchpit 26 and a cable security device 10 for securing the cable 14 relative to the catchpit 26, the cable security device 10, or a cable security device 10 in a neighbouring catchpit 26, preventing the removal of the cable 14 from the catchpit 26.

Referring next to figures 6 to 9, a further embodiment of the present invention is shown. This embodiment likewise is a cable security device 110, and it has four apertures 112 in a pair of plates 142, one of which is a front plate and the other of which is a rear plate. The two plates 142 can be identical and in this embodiment they are each formed of two parts -a top part 166 and a bottom part 168. The parts are delineated along corresponding edges that mesh together to provide the final plate 142. The corresponding edges include straight sections and arcs of the apertures 112.

The two plates 142 are arranged to be housed within a two-part frame 170, which frame has a top half 172 and a bottom half 174. The two halves join together using bolts 176.

Within the frame halves, a pair of beads are provided. Those beads define slots into which the edges of the plates 142 can slot. The beads could be made of a resilient material so as to seal against the surfaces of the plates.

The frame 170 and the plates 142 together form a cable security device 110 that defines an internal cavity.

On an edge of the frame, in this embodiment on a top wall of the upper frame, a port 180 is provided. This port facilitates the injection of a glue, an adhesive or a resin into the internal cavity. Once set, that glue, adhesive or resin provides the gripping mechanism for holding the cable relative to the cable security device.

Figure 7 shows the cables extending through the plates and out of the cable security device 110.

The specific positions of the apertures 112 is variable from one embodiment to the next Likewise, the size can be variable from one embodiment to the next. Indeed, there can be a variation of different sizes in a given embodiment, with each aperture having a blanking piece which gets removed to open given aperture. Thus, adhesive or resin will not exit unused apertures, and only the most appropriate aperture or apertures can be used.

Referring finally to figures 8 and 9, the plan view of figure 8 shows a hinged arrangement 182 for allowing opening and closing of the cable security device this could facilitate insertion of the plates 142. To allow the frame to be positioned around a cable, however, again the frame has a top half 172 and a bottom half 174, it thus being mountable over a cable that is already in situ.

Figure 9 on the other hand shows the positioning of the cable security device relative to the duct in the outside surroundings of the catchpit. The duct or conduit 24 extends away from the catchpit and carries the cables 14 to adjacent catchpits. Then, at the point of entry of the duct 24 into the catchpit 26, adhesive 188 adheres the cable security device 110 to the wall of the catchpit and potentially seals around the end of duct. The cable is therefore set in place in that position once the resin sets. This mode of use helps to eliminate access to the cable behind the guard/cable security device.

This second embodiment therefore allows an injection of a glue or resin around the cable. Front and back plates are made in two parts to allow retrofitting.

Regarding the port for injecting the adhesive resin, it preferably has a valve in it for one directional injection.

Figure 9 also shows a user connecting a resin gun 190, via a tube 192, to the port for easy injection purposes.

Although this second embodiment is shown to be made of two halves, defining a frame, and two plates, a similar embodiment could instead be provided by means of a pair or plurality of shells, or by way of a plurality of other components together defining an internal cavity for receiving the adhesive or resin, or having a hole with a collet or rubber grip, or the like. The external dimensions of this second embodiment, and other similar arrangements, are such as to be larger than the duct. As such, the body of the device forms the retaining mechanism for preventing the cable security device exiting the catchpit.

The present invention has been defined above purely by way of example. Modifications in detail may be made to the invention within the scope of the invention as defined in the claims appended hereto.

Claims

CLAIMS: 1. A cable security device comprising; a component with an aperture through it, the aperture being such that a cable can extend through it, a gripping mechanism for gripping that cable as it extends through that aperture; and a retention mechanism for holding or securing the cable security device relative a wall of a catchpit.
2. A cable security device according to claim 1 having a dimension, generally perpendicular to the axis of the aperture, of at least 105mm, or of at least 155mm, or of at least 230mm, or of at least 305mm.
3. A cable security device according to claim I or claim 2, wherein the component through which the aperture is provided is a plate.
4. A cable security device according to any one of the preceding claims, further comprising a housing for holding the component with an aperture through it.
5. A cable security device according to any one of the preceding claims, wherein the retention mechanism is adapted to secure or hold the housing and the plate relative to the wall of the catchpit.
6. A cable security device according to any one of the preceding claims wherein the retention mechanism comprises multiple plates, each to be retained within a frame.
7. A cable security device according to any one of the preceding claims wherein the or each plate takes the form of a stocks-like arrangement, with break-lines passing between the or each aperture, thereby allowing a separation of the pieces to open up the or each aperture, and a reassembly of the pieces to close the apertures.
8. A cable security device according to any one of the preceding claims wherein a frame envelops a plurality of plates in use.
9. A cable security device according to any one of the preceding claims having an internal space across which the cables will bridge when extending through it.
10. A cable security device according to claim 9, wherein the gripping mechanism is an adhesive or a resin located at least partially within the internal space.
11. A cable security device according to any one of the preceding claims, wherein the gripping mechanism comprises a collet.
12. A cable security device according to any one of claims I to 9, wherein the gripping mechanism is a collet.
13. A cable security device according to any one of the preceding claims, wherein the gripping mechanism comprises a two-part collet formed of two generally hemi-cylindrical members.15. A cable security device according to claim 11, claim 12 or claim 13, wherein the collet comprises a head for Jimiting the degree of movement of the collet through the aperture.16. A cable security device according to claim 15, wherein the collet has a tapered body extending in a reducing manner from the head.17. A cable security device according to any one of the preceding claims, wherein the gripping mechanism features an internal surface and gripping teeth on the internal surface for biting into the sheath of the cable.18. A cable security device according to claim 17, wherein the teeth are directed such that they grip the cable when that cable is exposed to a pulling force in a direction to cause the retention mechanism to bear more firmly towards the wall of the catchpit.19. A cable security device according to any one of the preceding claims wherein the gripping mechanism in use comprises a compressed rubber component.20. A cable security device according to any one of the preceding claims wherein the gripping mechanism comprises an adhesive or resin for bonding onto the cable or cables, thereby providing a mechanism for gripping the cable relative to the cable security device.21. A cable security device according to any one of the preceding claims taking the form of a pair of shells, or a collection of parts, which together can surround a cable or a plurality of cables, the shells or parts collectively defining an internal space in which the gripping mechanism can be located or housed, with the shells or parts forming the retention mechanism.22. A cable security device according to any one of the preceding claims wherein a port is be provided on the retention mechanism, or on a frame, for injecting an adhesive or resin into the device for setting against the cable or cables extending through the cable securtity device.23. A cable security device according to claim 22 wherein the port has a valve in it for one-way injection of the adhesive or resin.24. A cable security device according to any one of the preceding claims, wherein the or each aperture is tapered.25. A cable security device according to any one of the preceding claims, wherein the retention mechanism comprises one or more mountings for flexibly mounting the cable security device relative to the wall of the catchpit.26. A cable security device according to any one of the preceding claims, wherein the retention mechanism comprises legs or pins for bearing against a wall of a catchpit.27. A cable security device according to any one of the preceding claims, comprising a plate and a housing for containing the plate, the plate and the housing both featuring one or more holes through them, each sized to fit around a shaft of one or more wall-bearing leg of the cable security device.28. A cable security device of claim 27, wherein the shaft of the one or more leg is longer than the thickness of the plate.29. A cable security device according to any one of claims 26 to 28, wherein four legs are provided.30. A cable security device according to any one of claims 26 to 29, wherein the legs have heads that are larger than the shafts of the legs.31. A cable security device according to any one of the preceding claims, comprising a hanging eye on an edge thereof 32. One or more cable secured by a cable security device according to any one of the preceding claims, the cable having a minimal external diameter of 15mm.33. One or more cable secured by a cable security device according to any one of claims 1 to 31, the cable having a minimal external diameter of 20mm.34. One or more cable secured by a cable security device according to any one of claims 1 to 31, the cable having a minimal external diameter of 25mm 35. One or more cable secured by a cable security device according to any one of claims 1 to 31, the cable having a minimal external diameter of 30mm 36. One or more cable secured by a cable security device according to any one of claims I to 31, the cablehaving a minimal external diameter of 50mm.37. One or more cable according to any one of claims 32 to 36, the cable being an armoured cable.38. A catchpit comprising: an opening in a wall thereof for defining a passageway for one or more cables to pass into the catchpit from outside of the catchpit; and a cable security device according to any one of claims I to 31.39. A catchpit according to claim 38, wherein the opening is in a sidewall of the catchpit.40. A catchpit according to claim 38 or claim 39, wherein components of the cable security device are integrated onto, or integral with, the catchpit.41. A catchpit according to any one of claims 38 to 40, the catchpit further including a hooking point on a wall thereof onto which the cable security device can be mounted via a feature of the cable security device's retention mechanism.42. A catchpit according to any one of claims 38 to 41, wherein the cable security device is mounted on, or relative to, a wall of the catchpit.43. A catchpit according to claim 42, wherein that mounting of the cable security device places the cable security device over the opening.44. A catchpit according to claim 43, wherein the cable security device is on the inside of the catchpit.45. A catchpit according to any one of claims 38 to 44, wherein the cable security device is larger than the opening, at least in a dimension perpendicular to the axis of the aperture therethrough.46. A catcbpit according to any one of claims 38 to 45, wherein the catchpit is modular, it being formed of formed of at least a primary body, one or more extension components, each attached either above or below the primary body, and a cover and a base, the opening being provided in the primary body.47. A catchpit according to any one of claims 38 to 46, further comprising a hanging pin or a hanging hook at a top edge of the opening, onto which the cable security device can be, or is, mounted.48. A kit of parts comprising: plurality of different sized collets; and a cable security device according to any one of claims 1 to 31, the gripping mechanism comprising one of the plurality of different sized collets, that one being selected to fit the size of an aperture, that is drilled into the component on site so as to suit a particular cable thereat.49. Two catchpits, separated by a length of ducting, with a cable extending between the two catchpits through the ducting, wherein at least one of the catchpits features a cable security device according to any one of claims 1 to 31 in engagement with the cable, the cable extending through the aperture thereof 50. The catchpits of claim 49, wherein at least one of the catchpits is in accordance with any one of claims 38 to 47.51. A cable security device substantially as hereinbefore described with reference to any one or more of the accompanying drawings.52. A catchpit substantially as hereinbefore described with reference to any one or more of the accompanying drawings.