GB2185283A - Tension clamp - Google Patents

Abstract

A supporting tension clamp for an aerial bundled cable, comprising a clamping part 2, a stative part 1 for fastening of the clamping part e.g. on a wall surface of a building and a clamping device 15 adjoining to said clamping part for the locking of the cable within the clamping part. In order that the clamp could be easily mounted at different distances from the wall surface by means of the stative part, the stative part and the clamping part are seperate bodies provided with means for the interconnection thereof easily and rapidly and nevertheless reliably. The clamping part is advantageously provided with claws 5 defining a trough-like space; the stative part being provided with a rail-like part 6 essentially corresponding to said trough-like space of the clamping part of the interconnection of the clamping part and the stative part. <IMAGE>

Description

SPECIFICATION A supporting tension clamp for an aerial bundled cable The invention relates to a supporting tension clamp for an aerial bundled cable, comprising a clamping part, a stative part by means of which the supporting tension clamp is fastened e.g. on a wall surface of a building and a clamping device adjoining to said clamping partforthe locking of the cable within said clamp.

In relatively densely populated urbanized surroundings, aerial bundled cables (ABC-cables) are more and more extensively utilized in such a way that the cables are mounted on building walls e.g. underthe eaves or on the frontages thereof at points where they are not excessively unattractive in appearance. The provision of ground cables oropen cable paths, as distinctfrom cables drawn in the usual way, istherebyavoided. In this kind of installation work, clamps of the type mentioned a bove, for instance, have been used previously. Such clamps are made of hot-dip galvanized band iron by bending and partly by welding, whereby the clamp is provided with two legs forfixing on a wall and atrough-like partforming an integral body with said legs.Said trough-like part, which covers about two thirds of a circle, is intended for the supportionofthecable. Prior to the mounting of the cable in the clamp, an insert made of e.g. rubber and having a round cross-section has been provided around the cable, the diameter of said insert corres- ponding to that of the trough-like part ofthe clamp.

Thereafterthe cable and the insertthereofare locked in place within the clamp by a clamping device. One end of said clamping device is supported on one edge ofthe trough-like part and locked to the other edge thereof e.g. by means of a screw provided with a wing nut in order to tighten said clamping device around the cable. A disadvantage of such clamps, however, is thatthey are not resistantto tension in the axial direction ofthe cable. Furtherthey must be manufactured in many different sizes to enable application thereof in different kinds of installation points, e.g.

whenacorneroran eavemustbegonearound.

Besides, a clamp of this type is complicated in construction and rather difficult to manufacture.

So the object ofthe present invention is to provide a supporting tension clamp which is simple in construction as well as reliable and, further, easy and rapid to install and adapt to different kinds of installation places.

This is achieved bymeansofaclampforan ABC-cable according to the invention, in which clamp the stative part and the clamping part are separate bodies and provided with means for the interconnection thereof. In this way the clamping part is always the same structural element on which the stative part is secured. By providing the clamping part with claws defining a trough-like space, the stative part can be constructed even in situ e.g. offlat iron having a suitable cross-section by providing it with suitable bore holes by means of which the stative part is fastened both on the wall and on the clamping part.

Alternatively, the clamping part can, of course, be providedwitha rail-like part, the stative part being thereby correspondingly provided with a trough-like part which is essentially so constructed that it can be fitted in the rail-like partofthe clamping partforthe interconnection thereof. This kind ofstructure, however, is usually applicable only if a few sizes only ofthe stative part are needed, because it is practically impossible to construct a stative part of a required shape at the installation place.

For locking ofthe clamping partto the stative part, the clamping part is advantageously provided with a treaded hole through which a screw can be screwed from the clamping partto the stative part, whereby said stative part is provided with a hole opposite to the screw ofthe clamping part,the diameter of which hole is smallerthan that ofthescrew, the pointofthe screw being at least partly conical. In this way, the stative partand the clamping partcanbetightenedwith respect to each other also in case the stative part does not completely fill the trough-like space formed in the clamping part.

The supporting tension clamp according to the invention will be more closely described in the following with reference to the attached drawings, wherein Figure 1 illustrates a clamp according to the invention when provided with an installation insert of rubber.

Figure 2 illustrates another embodiment of the clamp according to the invention.

Figure 3 illustrates a clamping part of the clamp of Figure 1, and Figure 4 illustrates a stative part which is applicable with the clamping part shown in Figure 3.

The supporting tension clamp for an ABC-cable according to the preferred embodiment ofthe invention shown in Figure 1 comprises a stative part 1 and a clamping part2. In Figurel,theclamping partis provided with an installation insert 26 of rubber, by meansofwhich anABC-cablecanbeveryfirmly pinched in place within the clamping part. The use of the clamping part according to Figure 1 enables such a high holding force to be exerted on the installation insert 26 and, consequently, on the cable by means of the clamping device that the clamp according to the invention can be used also as an anchorclampfor relatively short air distances.

As appears from Figure 3 in particular, the clamping part 2 and the stative part 1 ofthe clamp according to Figure 1 are structural elements separate from each other. Said parts are interconnected with means 3. In the embodiment of Figure 1, the stative part 1 comprises planar parts 24which are intended to be mounted on a wall surface and, further, arms 23 which are atan angle with respect to said planar parts and which define the distance of the clamping part 2 from the wall surface. Aflat part 6 having an essentially right-angled cross-section is positioned between said arms 23, said flat part being so constructed that it can befitted in the trough-like space defined by the claws ofthe clamping part 2. Intheembodiment of Figure 1, said part6 having a right-angled cross-section is for reasons connected with the manufacturing thereof further lightened in such a mannerthatsaid part 6 is mainly formed by lugs projectingfrom the arms 23 and a planarportion 27 positioned atthejuncture of saidarms23,wherebya planarportion 25 provided on the locking member 2 restsagainstsaid planar portion 27. The planar pa rts 24 of the stative part are provided with holes 20 and 21, by means of which the stative partisfastened on a wall surface of a building using e.g. suitable bolts orthe like. Said hole 20 is elongated so as to enable the stative partto be tilted to some extent also afterthe installation ofthe fastening bolts.

The stative part 1 of Figure 1 as well as the stative part ofthe embodimentshown in Figure 2 can be easily manufactured by cutting off a suitable length of a profile made of an aluminium alloy by extruding and bythereaftermachiningthe required holes therein.

The clamping partshown in Figure 1 and, in more detail, in Figure 3 comprises a trough-like body 18 covering about two thirds of a circle, whereby a hook-like part 19 provided with a notch is provided at one end of said part 18, the other end being provided with a link 17.Aclamping device 15 is hinged on said link 17 bypassing the linkthrough a holeformed at one end ofthe clamping part body 18, whereby an edge ofthe clamping device 15forms a hinge pin 16. A lug 13 projects from the clamping device 15 adjacent the other end thereof a bult 11 provided with a base plate 14 being inserted through a hole provided in said lug. One end of said bult 11 will be positioned in the notch of the hook-like part 19 when the clamping device is in its closed position, whereby a counter nut 12 forthe bolt 11 can be placed underthe hook.By suitably shaping said nut 12, it can be locked in place in such a mannerthattheclamping device can be tightened solely by turning said bolt 11. One possible shape ofthe nut 12 is shown in Figure 1,wherein one surface on the nut is arched to correspond to the shape ofthe hook 19.

In orderto enable fastening ofthe clamping part2 on stative part 1 ,the clamping is provided with means 3 comprising claw-like hooks 5 and a locking screw 9 screwed into threaded boring 4. Said hooks 5 are provided on the outer surface ofthetrough-Iike part 18 essentially opposite to the clamping device 15. Said hooks 5 definetherebetween atrough-likespace,the cross-section of which is essentially right-angled. The stative part can be very easily fixed in said through-like space ifonlythe stative part is provided with a part having an essentially right-angled cross-section whereby the dimensions of said part should essentially correspond the dimensions of the trough like space.

Examples of such stative parts are shown in Figures 1 and 4. Said part having a right-angled cross-section does not need to fully correspond to the trough-like space in dimensions, but it may be slightly narrower and, particularly, lower, whereby the tightening is effected by means of the screw 9 apparent from Figure 2 in particular. Said screw can be screwed into said threaded boring 4 provided in the clam ping part 2 for said screw. Th e screw 9 adva ntag eously does not comprise any head,whereby it can be fully inserted within the clamping part body 18.On the other hand, the point portion of said screw is conical to some extent so thatit is able to push the stative part against the hook-like parts 5 In orderto ensure the locking in the axial direction, the stative part 1 is provided with a hole 10 (Figure 4) opposite to the hole 4 of the clamping part2.Thediameterofsaid hole loins somewhatsmallerthan that of the screw 9 but, however, largerthan that of the point of the screw.

Figure 4 illustrates another alternative construction of the stative part 1 to be used with the clamping part 2 of Figure 3. The stative part is therein made of metal flats having a right-angled cross-section, whereby it can be constructed even at the installation place if a suitable length of metal flats and a borring machine are at hand. The stative part according to Figure 4 comprises a planar part 24 which is intended to be mounted against the wall surface of a building by means of bolts orthe like which are passed through holes 21 provided in said part 24. Said stative part further comprises an arm 23 which is at an angle with respectto said part 24 and the length of which depends on the distance atwhich the clamping part is to be positioned from e.g. a wall surface.One end of said arm 23 is provided with an essentially planar part 22 in which a boring 10 is formed. Said part 22 is adapted for insertion in a trough defined by the hook-like parts 5 ofthe clamping part2 so asto be locked therein by means of a screw 9 which extends in said hole 10.

Figure 2 illustrates an alternative embodimentfor the embodiment shown in Figure 1. The structural elements of the embodiment of Figure 2 are indicated by the same reference numerals as the corresponding elements in the embodiment of Figure 1 with the exception of the means 3 by means of which the clamping part 2 is attached to the stative part 1. In the present embodiment, said means 3 areformed by a rail-like part 7 provided in the clamping part 2 opposite to the clamping device 15 and a trough-like part 8 formed between the ends of the arms 23 ofthe stative part. By dimensioning the rail-like part7 and the trough-like part 8 so that they correspond to each other, the rail-like part7 can be inserted intothetrough 8, thus providing a firm engagement, betweeen the clamping part2 andthe stative part 1.The clamping part can also in this case be locked in place by means ofthe locking screw 9 in the same way as the clampping partoftheembodimentof Figure 1.

The structural elements ofthe clamping part 2, the clamping device 15 and the clamping part body 18 shown in Figures 1 and 2 have such a shape that they can be extremely easily manufactured by cutting off suitable lengths of light-alloy metal profile made through extrusion and by thereafter machining therein the required narrowings, notches and holes. In this way the clamping part is made extremely advantageous in manufacturing costs. On the other hand, light-alloy metals are sufficiently firm for the purpose and, besides, they are not liable to corrosion, wherefore no kind of surface treatment is necessary.

The supporting tension clamp according to the invention is described above only by means oftwo specific embodiments and it is to be understood that these can be modified structurally in various ways without, however, deviating from the scope of protection defined in the attached claims.

Claims (7)

1. Supporting tension clampforan aerial bundled cable, comprising a clamping part, a stative part for fastening ofthe clamping part e.g. on a wall surface of a building and a clamping device adjoining to said clamping partforthe locking ofthe cable within the clamping part, the stative part and the clamping part being sepa rate bodies provided with means for the interconnection thereof.

2. Supporting tension clamp according to Claim 1, wherein the clamping part is provided with claws defining a trough-like space, the stative part being provided with a rail-like part essentially correspond ingtosaidtrough-likespaceoftheclamping partfor the interconnection ofthe clamping partandthe stative part.

3. Supporting tension clamp according to Claim 1, wherein the cross-section ofthe trough-like space of theclamping partandtherail-Iikepartofthestative part corresponding thereto is right-angled.

4. Supporting tension clamp according to Claim 1, wherein the clamping part is provided with a rail-like part,thestative part being provided with a trough-like part essentially corresponding to said rail-like part of the clamping partforthe interconnection of the clamping part and the stative part.

5. Supporting tension clamp according to any of the preceding claims, wherein the clamping part comprises a threaded hole for screwing of a screw from the clamping parttothe stative partforthe interlocking thereof.

6. Supporting tension clamp according to Claim 5, wherein the stative part is provided with a hole opposite to said screw, the diameter of said hole being smaller than that of the screw, and the point of the screw is at least partly conical.

7. Supporting tension clamp substantially as described herein with reference to the accompanying drawings.