FR2953655A1 - Fastening device for fixing of electric accessory e.g. distribution box, on cable rack of wire, has locking units formed on plate and associated to each hook to maintain corresponding wires engaged in hooks - Google Patents

Abstract

A fixing device according to the invention is intended for attaching an accessory (8) to a wire cable tray comprising longitudinal wires (22) interconnected by transverse wires (24). This device comprises a plate (2) which project two hooks (10, 12) forming a pair of hooks called the first pair of hooks. The two hooks (10, 12) are offset so as to cooperate with two parallel parallel wires (22) and are oriented in two opposite directions. Locking means (26, 30) made on the plate (2) are associated with each of the hooks (10, 12) in order to maintain a wire (22) engaged in the corresponding hook (10, 12).

Description

TECHNICAL FIELD TO WHICH THE INVENTION RELATES The present invention relates to a fastening device for attaching an accessory to a wire cable tray. A cable tray is used mainly to provide support, housing and protection of elongated elements such as electrical cables but also optical fibers or even tubes, for example pneumatic or hydraulic connecting tubes. These cable trays are then securely attached to a wall such as a wall or a ceiling. They can then themselves serve as a support for accessories, including electrical accessories. The present invention thus relates more particularly to the use of a cable tray and more particularly a cable tray son, as support for an accessory. The accessories most often found on cable trays are electrical accessories such as: a junction box, a stand-alone lighting and safety block (BAES), a stand-alone residential lighting unit (BAEH), a power socket, a clamp, a cable outlet, .... BACK TECHNOLOGY A wire cable tray generally has an elongated shape and a U-shaped section. It has longitudinal wires, called also warp threads, as well as transverse threads, also called weft threads. The warp yarns are substantially rectilinear while the weft yarns are U-shaped. The weft yarns are welded to the warp yarns thus forming a mesh. The raceway thus formed has a bottom for supporting cables, or the like, and the side walls, or wings, are intended to hold the cables or the like on the bottom of the raceway. There is generally a constant spacing between two warp son of the bottom of the cable tray. Similarly, for the wings of a cable tray, the warp son are also regularly spaced but with a different pitch from that found in the bottom of the raceway. Document FR-2,716,768 describes an accessory mounting element for a wire cable tray. The mounting element described comprises on the one hand means for fixing on a warp and secondly on a weft yarn. Thus, the attachment of an accessory must be close to a weft thread. The position of the accessory can not be freely chosen on the cable tray. In addition, several elements are necessary for mounting an accessory. The document EP-1 746 697 shows means for fixing an accessory on a cable tray son. This document includes a plate with elastic tabs which are arranged to adapt to different wire diameters and different wire spacings of a cable tray son. The solution proposed by this document does not allow, in certain cases, a sufficient maintenance of the accessory on the cable tray son. OBJECT OF THE INVENTION The object of the present invention is therefore to provide a fastening device intended for attaching an accessory to a cable tray made of wires which makes it possible at the same time to maintain the accessory and to mount it easily on the path of 15 cables in wires. Advantageously, the fixing device according to the present invention will make it possible to adapt to different distances between cable tray wires, may be positioned at different locations on a cable tray made of wires and / or will adapt to different wire diameters. To this end, the present invention provides a fastening device for attaching an accessory to a wire cable tray having longitudinal wires interconnected by transverse wires, said fixing device comprising a plate of which protruding two hooks forming a pair of hooks called the first pair of hooks, the two hooks being offset so as to cooperate with two separate parallel wires. According to the present invention, the hooks are oriented in two opposite directions, and locking means made on the plate are associated with each of the hooks in order to maintain a wire engaged in the corresponding hook. Such a fixing device makes it possible to carry out an assembly by rotating the plate with respect to the wire cable tray whereas in the devices of the prior art, the mounting is carried out by a translational movement. In addition, thanks to the locking means, the fastening means ensure good fixing avoiding an involuntary withdrawal of the mounted accessory. To better adapt to wires of different diameters that can be encountered in the same cable tray or from one cable tray to another, the fastening device according to the present invention proposes for example that each hook has a elastic tongue oriented towards the plate so as to allow a clamping of a wire placed in the hook. In order to fit on a side wing of a cable tray section or on the bottom of a cable tray, the spacings between two warp son are generally different at the side wing from the bottom of the cable tray, it is for example provided that the plate carries a second pair of hooks, the hooks of the second pair of hooks each projecting from the plate, being offset so as to each cooperate with a separate longitudinal wire and being oriented in two opposite directions, the offset between the hooks of the second pair of hooks being different from the offset of the hooks of the first pair of hooks, and in that locking means are associated with each of the two hooks of the second pair of hooks. hooks. A pair of hooks will for example be shifted to allow mounting on a side wing of a cable tray while the other pair of hooks will be shifted to allow mounting on the bottom of the cable tray. In a preferred embodiment of a fastening device according to the present invention, the locking means are advantageously snap-fastening means which retract elastically when a thread enters the hook and straighten up after the passage of the thread, when it is in place in the hook. Such means are easy to implement because no tool is then necessary for mounting a fastener on a section of cable tray. In a fastening device according to the invention, it can be provided that the hooks of a pair of hooks are oriented so as to be face-to-face or that the hooks of a pair of hooks are oriented so as to be back to back. When there are two pairs of hooks, there may be two pairs of face-to-face hooks, two pairs of back-to-back hooks, or a pair of face-to-face hooks and the other back-to-back hooks. to-back. The present invention also relates to: 3 - a plate intended to serve as an interface between a support and an accessory and comprising two opposite faces, characterized in that it has on one face a fixing device as described above and on the other face adapted means for fixing an accessory. - An accessory having a bottom, characterized in that the bottom of said accessory carries a fixing device as described above. An accessory according to the present invention can for example be included in the set of electrical accessories including junction boxes, autonomous lighting and safety units, autonomous residential lighting units, electrical outlets, clamps and cable outlets. Details and advantages of the present invention will become more apparent from the description which follows, given with reference to the appended diagrammatic drawings in which: FIG. 1 is a perspective view of a fixing device according to the present invention, FIG. FIG. 3 illustrates the mounting of the device of FIG. 1 on the bottom of a wire cable tray, FIG. 4 shows the mounting of the fixing device of FIG. 1 on a wing of a cable tray. Figure 5 is a view similar to Figure 4 for an alternative embodiment of the invention, Figure 6 illustrates the mounting of a junction box. Fig. 7 illustrates the mounting of a junction box with the fastening device shown in Fig. 5. Fig. 8 shows in perspective a third embodiment. 0 of a fixing device according to the present invention, FIG. 9 illustrates the mounting of the fastening device of FIG. 8 on a wire cable tray, FIG. 10 shows a fourth variant embodiment of a fastening device according to FIG. the present invention, and Figure 11 illustrates the mounting of the fastener of Figure 10 on a cable tray son. Figure 1 shows a fastening device according to the present invention. This figure shows a plate 2 which here has a substantially square shape. The thickness of this plate 2 is relatively small compared to the length of the sides of the square. This plate has two opposite faces, a first face subsequently called front face 4 and a second face subsequently called rear face 6. The front face 4 carries means for fixing the plate 2 on a cable tray son while that the rear face 6 has means for receiving a junction box 8 (see Figure 6). In the embodiment shown in Figure 1, the front face 4 is a substantially planar face of which project several elements. Note in particular the presence of hooks 10, 12. Each of these hooks is intended to cooperate with a son of a cable tray son as illustrated for example in Figures 2 and 3. Each of the hooks 10, 12 is intended for allow a snap on such a wire. Each hook 10, 12 has an arm 14 which overhangs the front face 4 extending parallel thereto. Each arm 14 is connected to the front face by a base. For the two hooks 10, a common base 16 carries two arms 14 while each of the hooks 12 is carried by an individual base 18. Ribs 20 between each base 18 and the front face 4 are provided to reinforce the hooks 12. To make a hooking of a wire using the hooks 10, 12, the plate 2 is positioned so that the wire is disposed between the front face 4 of the plate 2 and an arm 14 and bears against the corresponding base. Note in Figure 1 that the two hooks 10 are arranged back-to-back while the two hooks 12 are arranged face-to-face. The positions of the hooks 10, 12 on the plate 2 are determined to fit a cable tray son. In a manner known to the person skilled in the art, a section of wire cable tray comprises on the one hand longitudinal wires, called warp wires 22, interconnected by transverse wires, also called weft wires 24. In such a way, Conventional, and known to those skilled in the art, the weft son are U-shaped thus defining for the cable tray section a bottom and side wings.

Figure 2 illustrates the mounting of a plate 2 of Figure 1 on a side flange of a cable tray section. Here, the two hooks 10 are used to mount the plate 2. To achieve this assembly, the two hooks 10 are introduced between two longitudinal son of a side wing of the cable tray section and the plate is rotated as shown In the mounted position shown on the right in FIG. 2, it will be noted that the warp threads 22 are substantially parallel to two opposite sides of the plate 2 and that each of these warp threads 22 passes between the front face. 4 and an arm 14. For the rest of the description, platinum 2 will be associated with a reference frame (x, y, z). The x-axis corresponds to the direction given by the warp yarns in the mounted position of the plate on a cable tray section, the y-axis is perpendicular to the x-axis in the plane of the front face 4, and the z-axis is perpendicular to the front face 4. Note that the two hooks 10 are offset on the one hand along the x-axis and on the other hand along the y-axis. The offset along the y-axis makes it possible to adapt the position of the hooks 10 to the spacing between two warp yarns 22 of a lateral wing of the cable tray section. The hooks 10 are said to be oriented back-to-back because the arms 14 of these two hooks 10 extend each time from their common base 16 away from the other hook 10.

The offset along the x-axis of the hooks 10 influences the angle of rotation to be made by the plate 2 between its pre-mounted position (on the left in FIG. 2) when the hooks are introduced between two adjacent warp wires 22 and the mounted position in which the warp threads 22 are arranged on the one hand between the front face 4 and the arms 14 of the hooks 10 and on the other hand against the common base 16 of the two hooks 10. FIG. the mounting of a plate 2 on the bottom of a section of cable tray. Usually, the spacing of the warp son 22 in the bottom of a cable tray is different from the spacing of the warp son 22 on the wings of this section of cable tray. Here, the hooks 12 are used to allow the fixing of the plate 2 on the bottom of the cable tray section. Regarding the hooks 12, we note that they are also shifted firstly along the x-axis and secondly along the y-axis. The offset along the y-axis corresponds here also to the pitch between two warp yarns 22 of the cable tray section. As seen in Figure 3, the assembly with the hooks 12 is made by coming to position the plate 2 so that its front face 4 comes to press against two warp son 22, these two warp 22 located between the hooks 12. By then pivoting the plate 2 about the axis z (that is to say by maintaining the plate 2 in the same plane), the hooks 12 are hooked on the warp son 22, thus performing the mounting of the plate 2 on the bottom of the cable tray section. In its mounted position, the plate 2 has two sides substantially parallel to the warp threads 22. For each hook 12, there is a warp 22 resting against the corresponding base 18, this warp 22 being then between the face before 4 and the corresponding arm 14. The hooks 12 are considered here as being arranged face-to-face because the arm 14 of a hook 12 extends relative to its base 18 towards the other hook 12. Thus, in the mounted position, when the hooks are face-to-face the bases of the hooks are outside the two warp son on which the plate is mounted while when the hooks are arranged back-to-back, the base of the hooks carrying the assembly is between the two chain son 22 on which the plate is mounted.

The embodiment of Figure 1 also provides means for holding the plate 2 in its mounted position. Thus, with each hook 10, 12 are associated corresponding means for holding a warp 22 in said hook. In the embodiment shown, at each hook 10, is associated an elastic tab 26. There are therefore two elastic tabs 26 which are each formed by cutting in the front face 4. The free end of each elastic tab 26 presents to its free end a projection which forms a boss relative to the front face 4. To maintain a warp 22 extending along the x-axis, the elastic tab 26 extends substantially along the y-axis. It is disposed on the front face 4 so that, in the mounted position of the plate 2, the chain wire 22 hooked by the corresponding hook 10 is against said warp 22 on the same side thereof as the base 16 common but offset from the y-axis on the same side as the other hook 10. The skilled person will immediately understand from the view of Figure 2, that this position of the elastic tab 26 can create a stop during the rotation of the plate in the opposite direction to that which allowed its mounting. The locking means associated with the hooks 12 are here for each hook 12, formed by two resilient arms 30 whose free end protrudes from the front face 4, in the rest position of the elastic arm 30. Here, FIG. illustrates best the operation of the elastic arms 30. Here, in the mounted position of the plate, the warp thread hooked by a hook 12 is on the one hand between the base 18 of the hook 12 and the raised free end of the arms corresponding elastics. The elastic arms 30 could be arranged substantially in front of the corresponding base 18, but here they are slightly offset along the x-axis. This shift is made here on the opposite side to that of the other hook. This makes it possible to achieve better locking to try to prevent a pivoting of the plate 2 in the opposite direction of the pivoting made for its mounting on the cable tray section.

As for the elastic tabs 26, the elastic arms 30 are designed in such a way that, during assembly, the warp threads 22 come to retract the locking means and, as soon as the corresponding warp thread is in the mounted position , it releases the locking means returning to their rest position, in which they realize the locking. Thus, in the mounted position, the plate 2 is held on the one hand between the front face 4 and the arms 14, and to prevent rotation of the plate 2 relative to the warp son, four support points are provided, two formed by the bases 16, 18 hooks 10, 12 corresponding and two formed by the locking means 26, 30. Note the presence on each arm 14 of a resilient tongue 32. The latter extends substantially in the direction of the x-axis. When it is at rest, it projects from the arm 14 in the direction of the front face 4. Thus, the fixing means of the plate 2 can be adapted to wires of different diameters. The distance separating an arm 14 from the front face 4 is for example adapted to the wires of larger diameters that can be accommodated by the plate 2.

With the resilient tongues 32, if the plate 2 is mounted on a cable tray with chain son 22 of smaller diameter, the plate will still be well maintained. FIG. 4 shows the rear face 6 of the plate 2 of FIG. 1. Thus, in this figure, means are shown allowing the mounting on the plate 2 of a junction box 8, as illustrated in FIG. this embodiment, it is noted at the four corners of the plate 2, the presence each time of a rib 34 and a latching finger 36. The shape and position of these ribs and these latching fingers are adapted to allow the mounting of a junction box 8. Figure 6 shows a junction box 8 mounted on the plate 2 of Figure 1. By way of example, Figure 5 shows an alternative embodiment of the plate 2. The difference with respect to the plate of Figures 1 and 4 here relates to the rear face 6 of the plate. It should be noted here that the fastening means are distinct from those shown in FIG. 4. The fastening means here comprise pins 38 arranged at the four corners of the rear face 6 of the plate as well as a central pin 40 with deformable disks. elastically to ensure a maintenance when introduced into a cylindrical housing of suitable diameter. Figure 7 illustrates the mounting of a junction box on a plate 2 as shown in Figure 5. Figures 8 and 9 illustrate an alternative embodiment of a plate 2 according to the present invention. Here are repeated the same references as those already used previously to designate similar elements. There is thus a plate 2 with a front face 4 and a rear face 6. Note however that the plate 2 is not here square but of substantially rectangular shape. On the front face 4, there are four hooks 12. There are thus two pairs of hooks 12: a first pair is intended to allow the attachment of the plate 2 on two warp son 22 having a first spacing while the other pair of hooks 12 is intended to allow the attachment of the plate 2 on two warp son 22 having another spacing. The hooks 12 shown here are similar to the hooks 12 of Figure 1. There is also for each pair of hooks an offset along the x-axis and an offset along the y-axis of the two hooks. Here, each pair of hooks operates for face-to-face mounting.

Figure 9 illustrates the mounting of the plate of Figure 8 on a cable tray section. Such a section of cable tray, with such spacings between the warp son, does not exist and is drawn here for illustrative purposes only. Thus, FIG. 9 shows a fixing on a cable tray using the four hooks of the plate 2. It should be noted here that in the mounted position, elastic arms 30 are associated with each hook 12 to lock the inserted warp 22. in the corresponding hook 12. We find an operation here similar to that described above with reference to the embodiment of Figures 1 to 4.

It may be noted here that the plate 2 shown can be used for mounting on warp yarns 22 with three different spacings between the warp yarns. It is thus possible to mount this plate with wires spaced a distance "a", "b" or "c" as shown in Figure 9. Figures 10 and 11 illustrate another embodiment of a plate 2. Here, only hooks 10 are used. Each of these hooks are here also associated with elastic tabs 26 to allow locking of a warp 22 in the hooks 12. Here, the assembly on two warp threads 22 is back-to-back type. As for the previous embodiment, we can also consider fixing on warp son with three different spacings. One could even, in the case of an asymmetric mounting, as also for the embodiment of Figures 8 and 9, provide a mounting of the same plate on warp son with four separate spacings. Such an embodiment is not illustrated here. The fixing devices described above thus make it possible to attach an accessory to a wire cable tray by adapting on the one hand to the different wire spacings of a cable tray and on the other hand to the diameter of the wires. used for the realization of the cable tray son. The fixing means described above allow mounting and locking on a cable tray son without use of any tools. It is not even necessary to provide a screwdriver for locking or mounting an element. The description made above shows fixing means made on a plate. However, these means of attachment to a cable tray son could be directly on the back of an accessory. Thus, a junction box could integrate at its bottom, on the outside, a face such as the front face 4 of one of the plates 2 described above. A fastening device according to the present invention may be provided to be fixed on a side wing of a cable tray section or on the bottom of a cable tray. It may also be envisaged, in some cases, to mount the accessory at an angle between a warp thread of a side wing and a warp of the bottom of the cable tray section. The present invention is not limited to the preferred embodiments described above by way of non-limiting examples. It also relates to all the variants within the scope of those skilled in the art within the scope of the claims below. Thus, it could for example be envisaged for certain cable trays, or for small accessories, to have a fixing device having only a pair of hooks.

Of course, one would not go beyond the scope of the invention by providing hooks of a pair of hooks offset only along an axis.

Claims (9)

REVENDICATIONS1. Fastening device for attaching an accessory (8) to a cable tray made of wires having longitudinal wires (22) interconnected by transverse wires (24), said fixing device comprising a plate (2) of which project two hooks (10, 12) forming a pair of hooks called first pair of hooks, the two hooks (10, 12) being offset so as to cooperate with two parallel son (22) distinct, characterized in that the hooks (10, 12) are oriented in two opposite directions, and in that locking means (26, 30) formed on the plate (2) are associated with each of the hooks (10, 12) in order to hold a wire ( 22) engaged in the corresponding hook (10, 12). 2. Fastening device according to claim 1, characterized in that each hook (10, 12) has a resilient tongue (32) facing the plate (2) so as to allow clamping of a wire (22) placed in the hook. 3. Fastening device according to one of claims 1 or 2, characterized in that the plate (2) carries a second pair of hooks (10, 12), the hooks of the second pair of hooks each protruding from the plate (2), being offset so as to each be able to cooperate with a separate longitudinal wire (22) and being oriented in two opposite directions, in that the offset between the hooks (10, 12) of the second pair of hooks is different from the shifting the hooks (10, 12) of the first pair of hooks, and in that locking means (26, 30) are associated with each of the two hooks of the second pair of hooks. 4. Fastening device according to one of claims 1 to 3, characterized in that the locking means (26, 30) are latching means which retract elastically when a wire (22) enters the hook (10, 12) and straighten up after the passage of the wire (22), when it is in place in the hook (10, 12). 5. Fastening device according to one of claims 1 to 4, characterized in that the hooks (12) of a pair of hooks are oriented so as to be face to face. 6. Fastening device according to one of claims 1 to 4, characterized in that the hooks (10) of a pair of hooks are oriented so as to be back to back. 7. Platinum (2) intended to serve as an interface between a support and an accessory (8) and having two opposite faces (4, 6), characterized in that it has on one face (4) a fixing device according to one of claims 1 to 6 and on the other face (6) adapted means (34, 36; 38, 40) for fixing an accessory (8). 8. Accessory (8) having a bottom, characterized in that the bottom of said accessory carries a fixing device according to one of claims 1 to 6. 9. Accessory (8) according to claim 8, characterized in that it is included in the set of electrical accessories including junction boxes, autonomous lighting and security blocks, autonomous lighting units of home, outlets, clamps and cable outlets.