FR2809156A1 - Electric or telecommunication cable support ladder of pliable or bendable type has system for locking it in position when bent or folded - Google Patents

Abstract

The cable support ladder section can be transported in the pre-mounted state and includes in this state two side rails (1) and at least a rung (8). The two end parts (9) of this rung are hinged with respect to it around sensibly parallel axes. The rung includes first clamps (7) designed to hold it in the extreme deployed position in which the two side rails are farthest apart. Second clamps hold the rung in an extreme folded in which the two side rails are closest. Third clamps hold the rung in a position between the extreme deployed and bent positions. The three clamps include at least a stop against which a rung presses when the ladder is in the corresponding extreme deployed, folded or intermediate position. The stop part with a face which clips or slides onto a side rail.

Description

 Range <U> to <B> cable </ U> type foldable, <U> to <B> locking means in </ U> </ U> position <B> <U> unfolded </ U> The invention relates to the technical field of cable support systems or fluid transport conduits. </ B> </ B>

The invention particularly relates to support systems for electrical cables and / or telecommunications cables or the like.

Three main types of cable supports are known in the prior art: cable ladders, cable trusses, and chutes. The invention relates more particularly to cable ladders.

Cable ladders conventionally comprise two substantially parallel longitudinal members, between which extend ladders, sometimes referred to as transverse bars or bars, on which the cables lie, directly or through intermediate supports.

When placed in a horizontal position, the ladder must support the weight of the cables without excessive bending, the ladder itself being fixed on the structure of the building only at points spaced several meters apart.

Compared to other support systems, the advantages most often mentioned for cable ladders are - the possibility of installing large section cables; - good ventilation of the cables; - a greater spacing of the supports, with equal loads.

Examples of such cable ladders can be found in the following documents - French patent applications published under the numbers: 2 226 606, 2 300 887, 2 478, 2 588 426, 2 637 349, 2 640 025, 2 709 528; European patent applications published under the numbers 119 670, 339 699, 372 619, 373, 542 368, 641 964; international patent applications published under the numbers 84I04633, 88I04486, 90113164, 91I00973, 97I15774, 99I53584; German patent application published under the number DE-2141849; No. 5,465,929, 5,580,014 and 4,397,224. Several means have been envisaged in the prior art for fixing the rungs to the spars.

In an old technique, rungs and spars were welded. Such a method of assembly can lead to corrosion at the weld points when the longitudinal members and rungs are made of galvanized steel before welding: a galvanization performed before welding is easily damaged during welding. Post-weld galvanizing is an operation requiring a great deal of know-how when ladders and spars have sections to assemble complex shapes.

Some documents of the prior art describe the assembly of rungs to the spars by screwing, bolting, stapling, crimping or gluing.

For assembly by screwing the rungs on the longitudinal members, reference may be made, for example, to the document WO-A-97115774.

The stapling requires sparing at the ends of the ladder tongues, tenons, pins, or the like may be engaged in slots provided for this purpose in the longitudinal members. Thus, for example, the document FR-2 891 proposes that at least a portion of the rungs protrude through the beam opening, the permanent mounting of the rungs on the spars being ensured by deformation of the protruding parts of the rungs, by means of crimping.

Document FR-A-2 709 528 describes the implementation of the steps by interlocking on a rib of the longitudinal members, locking parts being then force-fitted to block the rungs in their nesting position.

The document FR-A-2 300 887 describes the assembly of rungs provided with pins penetrating into housings or openings formed on the longitudinal members, a hydraulic device then coming, at the right of each rung, to punch a burst in the spar, the song of the lower tear of this puncture abutting against the upper part of the echelon.

When cable ladders are pre-assembled with rigid assembly of rungs on the side members, the transport ladders is made expensive by their size. When cable ladders are transported in the fully disassembled state, their bulk can be reduced. However, a greater or lesser number of pieces are to be packaged. If these parts are packaged separately, packaging costs are increased. If the parts are packaged together, there is a risk that some assembly elements may have been omitted during packaging, which may put the installer at a disadvantage on the installation site.

To reduce transportation costs, while at the same time: - minimize the risk of missing parts; - Put the fitter on the job, it is known in the prior art to make folding cable ladders, ladders being pre-mounted on the side members, by riveting or screwing, ladder sections thus formed being transported to the folded state.

Such folding ladders, however, have the important disadvantage of being devoid of effective blocking means in the deployed position and / or folded.

So that there is a risk of inadvertent movements of these ladder sections, especially during their assembly.

These untimely movements can be troublesome when positioning ladder sections on their support.

These untimely movements can also be dangerous, the ladder sections behaving like shears, the editor's hands can be pinched during the abrupt folding of the rungs against the spars, this retreat being even more difficult to contain than the ladders Ropes consist of lengths of great length (conventionally 3 meters or 6 meters) and large masses, typically of the order of several tens of kilograms when the rails and rungs are steel.

The object of the invention is to provide a lightweight foldable cable ladder structure provided with means for temporarily locking in the folded and / or deployed position, this ladder structure being easy and safe to mount.

To this end, the invention relates to a cable ladder section of the foldable, which can be transported in the pre-assembled state and comprising in this state -mounted two longitudinal members and at least one step, the two end portions being articulated relative to the longitudinal members about substantially parallel axes, this section comprising first means adapted to ensure its maintenance in its deployed extreme position in which the two longitudinal members are substantially more distant.

The section also has the following characters, possibly combined according to various embodiments - it further comprises second means adapted to ensure its maintenance in its folded end position in which the two longitudinal members are substantially less distant <B>; </ B> - It further comprises third means adapted to ensure its maintenance at least one intermediate position between the extreme deployed and unfolded extreme; first, second and third means comprise at least one stop against which at least one step comes to rest when the ladder is disposed in the extended, folded or corresponding intermediate position; said abutment is defined by at least one face of a snapped or slidably mounted part, attached to a spar; said insert on said spar is an assembly splice of two cable ladder sections, said splice being slidably mounted in a groove of said spar; - The first, second, third means comprise a hole connecting member, the assembly member passing through at least one wall of the spar and being housed in a reservation provided for this purpose in at least one step; - The hole connecting member is placed substantially parallel to the axes of rotation of the rungs with respect to the longitudinal members - the assembly member with holes is a rivet or a pin held in its housing by a pin, or any other equivalent means.

In a particular embodiment, at least one of the longitudinal members of the cable ladder section comprises a groove in which is housed an end portion rungs, this groove having a cross section is U-shaped and being limited by a bottom wall, a wall upper and a bottom wall, the lower and upper walls being each pierced with through holes forming passages for pins or any other equivalent means defining axes of joints between rungs and spars; at least one of the walls of said groove may, moreover, be provided with passage holes of hole-connection members as previously defined. In a design mode, the stepped end portions are in the form of rectangular and open hollow sections, the peripheral wall of the rungs comprising the base wall; two side walls substantially opposite and perpendicular to the base wall; - two upper walls, substantially perpendicular to the side walls; According to one characteristic, the cable ladder section comprises at least one spar and / or at least one developed step pultruded composite material. Such a design allows a weight gain as well as a gain in the ratio of mechanical strength / linear mass, for the cable ladders obtained.

The invention also relates to cable ladders comprising at least one section as presented above.

Other objects and advantages of the invention will become apparent from the following description of embodiments, which description will be made with reference to the accompanying drawings in which FIG. 1 is a cross-sectional view of a spar of FIG. cable ladder provided with temporary blocking means in the deployed position, according to one embodiment of the invention; - Figure 2 is a partial schematic view along the plane 11-I1 of Figure 1; - Figure 3 is a sectional view along the plane 111-111 of Figure 2; - Figure 4 is a partial schematic top view of a cable ladder section provided with locking means according to another embodiment of the invention.

refers first to Figures 1 to 3.

Cable ladder comprises, as has been said above, two longitudinal members on which are mounted steps. The detailed description of embodiments of the invention will be made, for simplicity, in view of the mounting of an end portion of a rung on a spar.

It is understood that what will be said of this assembly of an end portion of step can be applied to the assembly of its other end portion on the other spar of the cable ladder.

By can be applied here means that the assemblies on the longitudinal members each of the two end portions of said rung may be substantially identical or equivalent.

In particular, the cable ladder may be provided with a plane of symmetry substantially perpendicular to said step, this plane being placed halfway between the two longitudinal members.

Similarly, what will be said of the mounting of an end portion of a rung may be transposed to the assembly of the end portions of the other rungs forming the cable ladder section.

In particular, the cable ladder section may be provided with substantially identical rungs mounted on the two substantially identical longitudinal members.

For simplification, the description will be made for spar 1 scaling cable substantially rectilinear and extending along said longitudinal direction D1.

The spar 1 will be described with reference to the figures, considering that this direction D1 is horizontal.

It is understood however that this direction D1 may not be horizontal when the cable ladder is in use situation.

It is also understood that the cable ladder may be curved.

This curvature may be in the plane, the cable ladder comprising for example - steps extending substantially in the same mean plane; - Two curved beams, the radius of curvature of the wings being constant or not, curvature only or several successive curvatures.

This curvature of the cable ladder may be out of plane, the cable ladder comprising for example - steps arranged relative to each other according to concave or convex mean plane, with a constant curvature radius or not, with only one curvature several curvatures successive; - Two longitudinal members, arranged facing one another, projecting relative to the average plane.

spar shown in Figure 1 comprises a groove 2, whose cross section, perpendicular to the direction D1, is U-shaped.

This groove 2 is limited by a bottom wall 3, an upper wall 4 and a bottom wall 5.

In the embodiment shown, the bottom wall 3 forms a base wall for the spar 1, and extends substantially in a direction D2, perpendicular to the direction D1.

In other embodiments, not shown, this bottom wall is spaced from the lower end portion of the spar.

walls 3,4 are, in the configuration of Figure 1, substantially symmetrical with respect to a plane S1 containing the directions D1 and In other embodiments, not shown, the walls 3 are substantially parallel to each other, but their widths , measured in the direction D2, are different. In variants or in combination, the thicknesses of the two walls 3,4 are different, these thicknesses being measured in the direction forming a direct trihedron with the directions D1 and D2.

walls 3,4 are each pierced with a through hole forming a passage for a pin or any other equivalent means, defining axis of articulation.

The upper wall 4 is further provided with a second hole 7 for passing a hole-type fastener such as a rivet 7 'or any other equivalent means.

The step 8 whose end portion 9 is adapted to be introduced into the groove 2 comprises - a first through hole 10; a second hole 11, crossing or not.

In the embodiment of FIG. 1, the end portion 9 of the step 8 is in the form of a hollow profile, the second hole 11 comes to pass through the peripheral wall 12 of the step. The section of the step may be rectangular and open, as shown in Figure 2. However, it is understood that this section may be circular, oval, square or polygonal. It is also understood that the step may be substantially full, at least in its extreme part 9.

In the configuration of Figure 2, the peripheral wall of the step comprises - a base wall 13; - two side walls 15,16 substantially opposite and perpendicular to the base wall 13; - two upper walls, substantially perpendicular to the side walls.

The end portion 9 of the step has a symmetry with respect to a plane S2 containing directions D2 and D3 and disposed halfway from the side walls 15,16.

The base wall 13 of the step is in contact with the lower wall 3 of the groove 2, while the two upper walls 17, 18 of the step are in contact with the lower face 19 of the wall 4.

If necessary, the contact between the walls of the rung and the walls 3,4 of the groove 2 of the spar may be accompanied by a slight friction.

This friction may be related to the presence of reliefs surfaces grooves and rungs placed opposite, or a substantially flared throat 2, tapering from its opening to its bottom wall.

The implementation of the step is carried out so that the first hole 10 passing through the step is placed in register with the passage 6 of the through holes formed on the walls 3,4 of the groove. When this operation is performed, an axis bar or a spindle, not shown, introduced into the passage 6 and comes to form articulation axis 20 of the step relative to the spar.

By this arrangement, the step can be in two extreme states compared to the spar - a first extreme state of unfolding of the ladder, wherein the echelon conventionally substantially perpendicular to the spar; - A second extreme state of folding scale, wherein the two beams are conventionally in contact.

In the embodiment of FIGS. 1 to 3, maintaining the ladder in its first extreme unfolding position is provided by a hole assembly member which is housed in the second hole 7 of the upper wall 4 of the throat. 3; - enter the second hole 11 of step 8.

This hole assembly member is for example an insert such as a rivet 7 'any other equivalent means.

In the configuration shown in FIG. 2, the hole 7 and the passage 6 are offset along the directions D1 and D2. In other configurations, not shown, the hole 7 and the passage 6 are shifted only in the direction D1 or the direction D2.

As it appears in FIG. 1, the spar 1 comprises, when in cross-section and in one embodiment - a side wall 21, the external face of which is provided with an external recess 22 forming an assembly groove with a shank. dove; an upper wall 23 forming a receiving and / or supporting surface for a lid, eg snapped-on.

The spars and rungs can be made of metal alloy, polymer material or composite. In a particular embodiment, the longitudinal members and / or rungs are made of pultruded composite material.

The rungs and spars may be of identical material or Referring now to Figure 3 which illustrates another embodiment blocking means in the deployed position of the cable ladder. In an embodiment, an insert 24, sliding in the groove 2 or being latched laterally on the spar, is supported both on the rung and on the spar.

When this insert 24 is in place, the spar and the step mounted relative to each other about the axis 20 defined previously, are substantially blocked.

In a particular embodiment, this insert 24 is an assembly splice of two cable ladder sections as shown. What has just been said with reference to FIGS. 1 to 4 concerns the locking in deployed position of foldable cable ladders, the rungs then being substantially perpendicular to the longitudinal members.

It is understood, however, that the invention also relates to the case where the rungs can be kept locked in rotation relative to the longitudinal members, without being substantially perpendicular.

For this purpose, starting from the embodiment of FIGS. 1 to 3, it suffices to provide several holes 11 in the end part of the assembly of the step, these holes being arranged in a circle centered on the axis 20. In a variant, starting with of the embodiment of Figure 4, the insert 24 will have a side face 25 inclined relative to the cross section of the beam of an angle substantially equal to that desired between rungs and longitudinal members.

It is thus possible to maintain the cable ladder in a more or less fully deployed position.

It is also understood that the invention also relates to the case where it is desired to temporarily maintain the cable ladder in the folded position. For this purpose, starting from the embodiment of FIG. 4, the insert 24 will have a lateral face inclined with respect to the cross section of the spar by an angle substantially equal to that defined by the rungs and spars, when the cable ladder is folded.

The maintenance of the cable ladder in the folded or unfolded position as just described is easy both transport and assembly, this assembly may include additional measures for blocking the steps in position.

Claims (1)

<B> <U> CLAIMS </ U> </ B>. Foldable type cable ladder section, which can be transported in the "assembled" state and comprising in this pre-assembled state two longitudinal members (1) and at least one step (8), the two end portions (9) of this step (8) being articulated with respect to the longitudinal members (8) about substantially parallel axes (20), this section being <B> characterized </ B> in that it comprises first means (7 ', 24) adapted to ensure its maintenance in its deployed extreme position in which the two longitudinal members (8) are substantially the most distant rope ladder section according to claim 1, <B> characterized </ B> in that it comprises in in addition to second means adapted to ensure its maintenance in the folded extreme position in which the two longitudinal members are substantially the least distant 3. Cable ladder section according to claim 1 or <B> characterized </ B> in this further comprises third means able to maintain it at least one in intermediate between the extreme deployed and the extreme unfolded. 4. Cable ladder section according to any one of claims 1 to 3, characterized in that the first, second, third means comprise at least one stop against which at least one step (8). ) is supported when the ladder is disposed in the deployed extreme position, folded or corresponding intermediate. 5. Cable ladder section according to claim 4, characterized in that said stop is defined by at least one face (25) of a part (24) latched or slidably mounted, attached to a spar 6. Section of cable ladder according to claim 5, characterized in that said piece (24) attached to said spar (8) is an assembly splice of two cable ladder sections, said splice being mounted sliding in a groove (2) of said spar. 7. Cable ladder section according to any one of claims 1 to 6, characterized in that the first, second and third means comprise a hole connecting member (7 '), this assembly member passing through at least one wall (3,4) of the spar (1) and being housed in a reservation provided for this purpose in at least one step (8). Cable ladder section according to Claim 7, characterized in that the hole connecting member is positioned substantially parallel to the axes of rotation of the rungs (8). relative to the longitudinal members (1). 9. Section of cable ladders according to claim 7 or 8, characterized in that the hole-type fastener is a rivet, a pin held in its housing by a pin, or any other equivalent means. 10.Structure of cable ladders according to any one of claims 1 to 9, characterized in that at least one of its longitudinal members comprises a groove (2) in which is housed an extreme portion step, this groove (2) having a cross section is shaped and being limited by a bottom wall (3), an upper wall (4) and a bottom wall (5), walls (3,4) being each pierced with through holes forming passages for pins or any other equivalent means defining axes of joints (20) between rungs (8) and longitudinal members (1). Cable section according to Claim 10, characterized in that at least one of the walls (B) of said groove (2) is additionally provided with holes (7) for the passage of assembly members (T) as defined in claims 7 to 9. 12. Cable ladder section according to any one of claims 1 to 11, characterized by <B> in that the end portion (9) of the rungs (8) are in the form of a rectangular and open hollow profile, the peripheral wall rungs comprising a base wall (13); - two side walls (15,16) substantially facing and perpen dicular to the base wall (13); - two upper walls, substantially perpendicular to the side walls. 13. Section of cable ladder according to any one of claims 1 to 12, characterized in that its longitudinal members comprise when seen in cross section - a side wall (21), the outer face of which is provided with an external recess (22) forming a dovetail assembly mortise; - An upper wall (23) forming receiving surface and / or support for a lid, for example latched. 14. Section of cable ladder according to any one of claims 1 to 13, characterized in that comprises at least one spar and / or at least one developed step pultruded composite material.