Bridle ring

Abstract

A bridle ring 20 for supporting electrical cables comprising an upper attachment point 22, a first support element 30 defining a hook pointing in a first direction, and a second support element 32 def

Description

FIELD OF THE INVENTION The present invention relates to a bridle ring. BACKGROUND ART A bridle ring is a cable support fixture, usually designed in a ring shape to hold and suspend cable bundles from ceilings, walls, beams, and the like or under raised floors. Typically metallic, the ring is usually formed from a length of steel rod which is bent into a spiral consisting of one or slightly more than one complete turn. This is then fixed to the supporting surface such as a ceiling allowing cables to be passed through the ring to support them. The top of the ring is open due to its spiral nature, allowing insertion of cables without the need to thread them through the ring. A series of such rings can be spaced regularly along a cable run in order to support the cable or cables along their length, usually every 600mm or so. SUMMARY OF THE INVENTION The present invention provides a bridle ring for supporting electrical cables, comprising an upper attachment point, a first support element defining a hook pointing in a first direction, and a second support element defining a hook pointing in a second and opposite direction, the two support elements being adjacent but spaced apart at their lowest point. This offers a number of advantages over a known bridle ring. The presence of two support elements rather than just one means that the weight of the cable is divided between two support points, roughly halving the pressure exerted on the cable insulation and thus reducing the rate at which it degrades. Further, a new cable can be inserted into the bridle ring from below, by pushing it upwards in the spaced-apart region between the two support elements and twisting it into place to rest on the two hooks. Existing bridle rings require access from above, which is less convenient and may be impossible in complex cable layouts. The invention therefore obviates the need to thread the cable through the ring, a process which can damage the insulation layers of the cable. We prefer that each support element extends downwardly from the upper attachment point. The support elements can comprise a loop, each loop ideally extending in opposite directions. The loops can each extend along a helical path, in which case we prefer that the two helical paths extend in opposite horizontal directions. Each loop preferably encompasses more than 180 degrees and less than 360 degrees of the helical path starting from the upper attachment point, more preferably between 225 degrees and 315 degrees. The bridle ring defined above can be formed from a rod of metal such as steel, ideally a single length of metal rod defining from one end to the other thereof the support element, then the upper attachment point, and then the second support element. A diameter of between 4 and 6mm is suitable, being easily formable to shape without requiring excessive forces, but strong enough to withstand loads in use and during installation. BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the present invention will now be described by way of example, with reference to the accompanying figures in which; Figure 1 shows a view from one side of bridle rings according to the present invention in use above a suspended ceiling; Figures 2 to 5 show perspective, front, side and top views (respectively) of a single bridle ring according to the present invention; and Figure 6 shows a schematic view of a set of installed bridle rings, from beneath. DETAILED DESCRIPTION OF THE EMBODIMENTS Figure 1 shows a typical installation of a run of cables 10 in the space or void between a solid ceiling 12 and a suspended ceiling 14. In the usual manner, the suspended ceiling 14 comprises a plurality of ceiling tiles 16 supported on a grid 18. The grid 18 is held in place below the solid ceiling by struts 18 which are fixed to the solid ceiling, and at its edges (not shown) by fixings into the vertical wall of the room. Often, some ceiling tiles are omitted in favour of lighting units, for which electrical power needs to be supplied. Other electrical items such as movement sensors or smoke detectors may be included in the suspended ceiling, and the ceiling void (i.e. the space between the solid ceiling and the suspended ceiling) is also sometimes used as a convenient location for data cables. Cabling for these and for other purposes needs to be supported safely, and bridle rings are a common means for doing so. A bridle ring 20 is attached to the solid ceiling 12 and includes a hook element for holding the cables 10 which extends downwardly from the point of attachment and thus into the ceiling void. Most known bridle rings are fashioned from a rod which extends downward and which curls through about 400 degrees or more around a helical path to define a ring. Thus, the path defines a ring through which the cables 10 can pass. Disturbance of the cables 10 from side to side such as during handling or during a seismic event will not cause the cables 10 to fall out of a known bridle ring, since the rod extends through more than a complete turn and thus there is no open path to one side or the other through which the cables 10 can fall. As the rod follows a helical path, there is a gap at the upper part of the ring allowing cables to be inserted into the bridle ring by lifting them above the bridle ring, twisting so that they can pass through the gap, and allowing them to settle into the ring. Figures 2 to 5 show the bridle ring 20 of the present invention in more detail. An attachment point 22 at the top of the ring 20 allows it to be fixed to a solid ceiling 12. In this case, the bridle ring 20 is formed from a single length of 5mm diameter steel rod 24 and the attachment point 22 is defined by a loop 26 formed in the rod at or close to its middle point. This creates a 6.5 mm diameter hole 28 through which a screw or like fixing can pass to secure the bridle ring 20 to the solid ceiling 12. A wide range of such fastenings will fit, thus making the illustrated embodiment a universal type of cable bridle ring. Two support elements 30, 32 depend from the attachment point 22. Each is in the shape of a helical part-loop, extending through 270 degrees so as to wrap around one side and halfway up the other side, thus defining a hook. The two support elements 30, 32 are disposed in opposite orientations, hence forming two opposing loops or two hooks facing in opposite directions. As they follow a generally helical path, they are spaced apart at their lowest point 38 due to the pitch of the helix. A cable can be introduced into the bridle ring 20 by pushing it upwards through this gap 38 and then twisting or turning the cable (or the bridle ring 20) to allow the cable to rest on the two support elements 30, 32. This orientation provides two points of the support for the cables rather than just one (as is conventional), and permits ease of wiring without having to thread cables past one another, minimising the risk of tangling cables or burning their insulation. It is also considerably quicker. Thus, this design of bridle ring is able to save time and help to mitigate risks associated with electrical fires while also ensuring compliance with regulations. For ease of manufacture, each part-loop comprises an initial straight section 34 after which the rod 24 curves smoothly at 36 through the required angle. Generally, perfect adherence to a particular geometric shape is not necessary in this context and thus when we refer to loops, helical paths, angular extents and the like we intend these to be interpreted loosely to indicate the general, overall path of the element in question. The bridle ring 20 could be produced in a range of sizes such as a 75mm radius loop, or a greater or lesser radius. Figure 6 illustrates one advantage arising from inserting cables into the bridle ring from below. It shows a schematic view of a set of installed bridle rings 20, from beneath, supporting a group of cables 10 which run from a left side as illustrated. On reaching the central bridle ring 20, the required paths for the cables within the group 10 is for a sub-group 10a to continue onwards towards the right, for one cable 10b to divert upwards (as illustrated), and for a last cable 10c to divert downwards (as illustrated). Thus, at the central bridle ring 20 there is a group of cables 10, 10a from which extends a cable 10b, 10c in either lateral direction. In the event that a further cable needs to be added to the group 10, for example following the straight-on path 10, 10a, then in the case of conventional bridle rings for which the cable needs to be inserted from above, this is not possible as the cable cannot be lifted into position above the entrance gap to the bridle ring since access on either side is blocked by the laterally-extending cables 10b, 10c. Thus, the tradesperson installing the new cable wilI have no option but to thread the cable through the bridle rings. This will inevitably involve sliding the new cable through the bundle of existing cables thus dragging their insulation layers over each other, a process which generates frictional heat in the insulation layers and can cause degradation of the insulation material. 5 Through use of the bridle ring according to the present invention, the new cable can be inserted into the ring and join the existing bundle of cables from below. This is considerably easier for the tradesperson and does not necessitate any potentially-harmful frictional sliding. As a result, the new cable can be inserted more quickly, saving time and cost, and once installed the insulation of the new cable will be in good condition allowing a longer and safer 10 service life. It will of course be understood that many variations may be made to the abovedescribed embodiment without departing from the scope of the present invention.

Claims

1. A bridle ring for supporting electrical cables, comprising an upper attachment point, a first support element defining a hook pointing in a first direction, and a second support element defining a hook pointing in a second and opposite direction, the two support elements being adjacent but spaced apart at their lowest point.

2. A bridle ring according to claim 1 in which each support element extends downwardly from the upper attachment point.

3. A bridle ring according to claim 1 or claim 2 in which each support element comprises a loop, each loop extending in opposite directions.

4. A bridle ring according to claim 3 in which each loop extends along a helical path.

5. A bridle ring according to claim 4 in which the pitches of the two helical paths extendin opposite horizontal directions.

6. A bridle ring according to any one of claims 3 to 5 in which each loop encompasses more than 180 degrees and less than 360 degrees of the helical path starting from the upper attachment point.

7. A bridle ring according to claim 6 in which each loop encompasses more than 225 degrees and less than 315 degrees of the helical path starting from the upper attachment point.

8. A bridle ring according to any one of the preceding claims, formed from a metal rod.

9. A bridle ring according to claim 7, formed of a single length of metal rod defining fromone end to the other thereof the support element, then the upper attachment point, and then the second support element.

10. A bridle ring according to claim 7 or claim 9, in which the metal rod has a diameter between 4 and 6mm.

11. A bridle ring according to any one of claims 7 to 10 in which the metal rod is steel.CLAIMS1. A bridle ring for supporting electrical cables, comprisingan upper structure configured to provide an attachment point to fix said bridle ring to a surface,a first support element defining a hook pointing in a first direction, anda second support element defining a hook pointing in a second and opposite direction,the two support elements being spaced apart at their lowest point thereby to leave a gap therebetween, andformed of a single length of metal rod of substantially uniform thickness defining from one end to the other thereof, the first support element, then the upper structure, and then the second support element, wherein the first support element and the second support element each extend along a helical path.

2. A bridle ring according to claim 1 in which each support element extends downwardly from the upper attachment point.

3. A bridle ring according to claim 1 or claim 2 in which each support element comprises a loop4. A bridle ring according to claim 3 in which the pitches of the two helical paths extend in opposite horizontal directions.

5. A bridle ring according to claim 3 or claim 4 in which each loop encompasses more than 180 degrees and less than 360 degrees of the helical path starting from the upper attachment point.

6. A bridle ring according to claim 5 in which each loop encompasses more than 225 degrees and less than 315 degrees of the helical path7. A bridle ring according to any one of the preceding claims, in which the metal rod has a diameter between 4 and 6mm.

8. A bridle ring according to any one of the preceding claims in which the metal rod is steel.

9. A bridle ring according to any one of the preceding claims in which the attachment point is defined by a loop formed by the rod at or close to its middle point.

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