HYBRID CABLE TRAY AND MANUFACTURING METHOD OF THE SAME

Abstract

Hybrid cable tray comprising a first part (13) constituting one piece having a uniform thickness. The first part (13) forming at least a first support surface (52) of a first accommodation (53) for the plurality of cables (54). The first part (51) having a plurality of first through holes (15) formed by a first plurality of edges (20) in the first part (13). The cable tray (10) having two parallel extending side bars (11, 12) connected to each other by said first part (13). The said side bars comprise an inner side (111, 121) connected to the said first part (13) and provided with at least one closed top side (113, 123) and one outer side (112, 122) where the inner side and the outer side have about the same width (W). The side bars have an open bottom side (55, 56). The invention also covers a method of manufacturing such a hybrid cable tray (10).

Claims

1. A hybrid cable tray comprising: a first part comprising one piece having a uniform thickness, the first part forming at least a first support surface of a first accommodation for the plurality of cables, the first part having a plurality of first through holes formed by a first plurality of edges in the first part; and two parallel extending side bars connected to each other by the first part, the side bar having an inner side connected to the first part and with at least one closed top side and one outer side and an open bottom side, wherein the closed top side of the side bar comprises two flat surfaces symmetrically arranged in the side bar with an angle towards each other where the angle is in the interval of 45-60 and together providing a top edge of the closed top side of the side bar.

2. The hybrid cable tray according to claim 1, wherein at least one side bar, preferably both side bars, is formed from the one piece.

3. The hybrid cable tray according to claim 1, wherein the inner side and the outer side have about the same width.

4. The hybrid cable tray according to claim 1, wherein at least a part of each of the plurality of edges protrudes and is directed with an angle away from the support surface of the first accommodation, where 45<<180.

5. The hybrid cable tray according to claim 4, wherein the first plurality of edges of the at least one through hole is orientated at the angle from the support surface.

6. The hybrid cable tray according to claim 5, wherein the plurality of edges of the at least two adjacent through holes in the first part is orientated at the angle from the support surface.

7. The hybrid cable tray according to claim 1, wherein the through holes are formed and located in relation to each other so that the plurality of edges of two adjacent through holes defines a tray member formed as a beam with longitudinally uniform cross shape at least partly between adjacent located through holes, preferably the beam having a cross section in the form of a U-profile.

8. The hybrid cable tray according to claim 1, wherein the outer side of the side bar is provided with an outer rim extending substantially perpendicular out from a bottom edge of the outer side of the side bar.

9. The hybrid cable tray according to claim 1, wherein the inner side of the side bar is provided with an inner rim extending substantially perpendicular inwards from a bottom edge of the inner side of the side bar and to which the inner rim of the first part is attached.

10. The hybrid cable tray according to claim 1, wherein the inner side and/or the outer side of the side bar is provided with attachment means, preferably in the form of holes.

11. A method of manufacturing a hybrid cable tray, for example for supporting electrical wires, where a flat metal sheet starting material having one side surface as a support surface for an accommodation for a plurality of cables, the sheet material being processed by the following steps: a) the metal sheet material being punched with a plurality of through holes having a plurality of edges; b) bending at least a part of one of the plurality of edges an angle away from the support surface; c) bending a flat side area of the metal sheet into a longitudinal side bar or attaching a longitudinal side bar to the metal sheet, the side bar comprising an inner side connected to a first part and with at least one closed top side and one outer side and an open bottom side, characterized in that the closed top side of the side bar comprises two flat surfaces symmetrically arranged in the side bar with an angle towards each other where the angle is in the interval of 45-60 and together providing a top edge of the closed top side of the side bar.

12. The method according to claim 11, wherein, in step a) the metal sheet material is punched with through holes which are separated by strips; and wherein in step b) the strips are being formed into beams defined as tray members.

13. The method according to claim 11, wherein an opposite flat side area of the metal sheet is also bent into a longitudinal side bar.

14. The method according to claim 11, wherein step a) also involves punched holes as attachment means intended for mounting purposes.

15. A hybrid cable tray comprising: a first part constituting one piece having a uniform thickness, the first part forming at least a support surface of a first accommodation for the plurality of cables, the first part having a plurality of first through holes formed by a first plurality of edges in the first part; and two parallel extending side bars interconnected to each other by the first part, the side bar having an inner side connected to the first part and with at least one closed top side and one outer side and an open bottom side, characterized in that the closed top side of the side bar comprises two flat surfaces symmetrically arranged in the side bar with an angle towards each other where the angle is in the interval of 45-60 and together providing a top edge of the closed top side of the side bar; wherein the inner side and the outer side have about the same width; wherein at least a part of each the plurality of edges protrudes and is directed with an angle away from the support surface of the first accommodation, where 45<<180; and wherein the first plurality of edges of at least one through hole is orientated at the angle from the support surface.

16. The hybrid cable tray according to claim 15, wherein the first plurality of edges of at least two adjacent through holes in the first part is orientated at the angle from the support surface.

17. The hybrid cable tray according to claim 16, wherein the through holes are formed and located in relation to each other so that the plurality of edges of two adjacent through holes defines a tray member formed as a beam with longitudinally uniform cross shape at least partly between adjacent located through holes, preferably the beam having a cross section in the form of a U-profile.

18. The hybrid cable tray according to claim 17, wherein the outer side of the side bar is provided with an outer rim extending substantially perpendicular out from a bottom edge of the outer side of the side bar.

19. The hybrid cable tray according to claim 18, wherein the inner side of the side bar is provided with an inner rim extending substantially perpendicular inwards from the bottom edge of the inner side of the side bar and to which the inner rim the first part is attached.

20. The hybrid cable tray according to claim 19, wherein the inner side and/or the outer side of the side bar is provided with attachment means, preferably in the form of holes.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The invention will now be described in more detail with reference to exemplifying embodiments thereof illustrated in the accompanying drawings, in which

[0045] FIG. 1 illustrates in perspective an embodiment according to the present invention;

[0046] FIG. 2 discloses a bottom view of the embodiment in FIG. 1;

[0047] FIG. 3 discloses an enlarged view III from FIG. 2;

[0048] FIG. 4 discloses a side view of the embodiment in FIG. 1;

[0049] FIG. 5 discloses an end view of the embodiment in FIG. 1;

[0050] FIG. 6 discloses a top view of the embodiment in FIG. 1;

[0051] FIG. 7 illustrates in perspective an end view from below of the embodiment in FIG. 1;

DESCRIPTION OF THE INVENTION

[0052] FIG. 1 illustrates a first embodiment of a hybrid cable tray 10 of a mesh/ladder/wire type. The cable tray is provided with a first side bar 11 and a second side bar 12 which side bars both are attached longitudinally to separate sides of a first part 13, being a bottom part, of the cable tray 10. Each side bar 11, 12 has an inner side 111, 121 connected to the said first part 13 and an outer side 112, 122 connected to the respective inner side 111, 121 by a closed top side 113, 123. In the figure the initial forming operation of a flat starting metal sheet material by punching and pressing the sheet material has formed first tray members 14 extending in the longitudinally direction 15 of the cable tray 10 and second tray members 16 extending in the transversal direction perpendicular to the longitudinal direction 15, indicated by the centerline in the figure, of the cable tray 10. The form of each tray member 14, 16 is as beams each of which having a cross section in the form of a U-profile 17 with the open side of the U-profile directed outwards from the cable tray 10. Between the tray members 14, 16 the cable tray 10 is provided with through holes 18 over the whole first part 13. For specific purposes a hole can be covered by a cover means or by the metal sheet material not being initially punched.

[0053] After the initially punching step forming the through holes 18 and also a number of mounting holes as attachment means 19 in the flat metal sheet material, a second step defined as a strip forming operation is taken place. During this strip forming operation the excess border material along all openings and all edges in the first part are bent 90 in the same direction from the flat surface of the starting metal sheet surface. This strip forming operation contains both a bending operation and a plastic forming operation of the metal sheet. The tray members is a result from this bending operation where edges 20 of said through holes 18 has been bent an angle thus forming these members. The possible angles for making up these tray members is in the interval of 45<<180. The angle 180 corresponds to a circular cross section of the tray member and an angle of 90 corresponds to a U-shaped cross section of the tray member. A further method step is to bend the flat outer areas on both sides of the starting metal sheet into the first and second side bars 11, 12. The result of the starting metal sheet material after these forming steps is disclosed in FIG. 1.

[0054] The first step being a punching operation and the second step being a forming operation can be made in a single combined punching/forming operation step, however punching by making openings and forming by bending and stretching the edges will be made during such a combined step.

[0055] FIG. 2 discloses a bottom view of the cable tray 10 with the beams in the form of first tray members 14 and second tray members 16. Also a cover member 21 and its mounting hole 22 can be seen in the figure. Cover member/members with the respective mounting hole can of course be located in one or more of the openings located on the side parts of the cable tray. These cover members can be provided as closed through holes produced by not stamping such through holes in the metal plate in the production step of the cable tray. Other types of attaching means for various devices other than mounting holes can be provided in the cover member. As is recognized from this bottom view is that the U-shaped beams are orientated so that the open side of the beams cannot be seen in a top view of the cable tray. The through holes 18 in the cable tray are in this embodiment rectangular. It is also clear from the figure by the curved center lines that cable trays according to the invention can be produced in different suitable lengths. The connections III between each first tray member 14 and each second tray member 16 are made as part of the members since the tray members are produced from the same sheet of metal. Each side bar 11, 12 are provided with an outer rim 23 extending substantially perpendicular out from the bottom edge of the outer side 112, 122 of the respective side bar 11, 12. Furthermore, the inner side 111, 121 of the respective side bar 11, 12 is provided with an inner rim 24 extending substantially perpendicular inwards from the bottom edge of the inner side of the respective side bar 11, 12 and to which inner rim 24 the said firs part 13 is attached. Preferably the outer rim 23 and the inner rim 24 together define flat surfaces which are flush with each other defining a support surface.

[0056] The open profiles facing in the same directions in the cable tray has the advantages of that the cable tray sections can be stacked on each other requiring minimum extra storage volume at transport of the cable trays.

[0057] FIG. 3 discloses en enlargement view III from FIG. 2 of the connection area 31 between a first tray member 14 and two second tray members 16. The connection area 31 also constitutes an open profile corresponding to and being aligned with the U-shaped tray members 14, 16. This connection area 31 has been produced simultaneously with the tray members in an elastically forming operation.

[0058] FIG. 4 discloses a side view of the cable tray 10 where the side bar 12 is provided with attachment means 19 in the form of various shapes of holes in the outer side 122 of the side bar. Also the closed top side 123 of the side bar 12 is indicated in the figure.

[0059] FIG. 5 is an end view of the cable tray 10 in FIG. 1 clearly disclosing that the longitudinally directed tray member having a U-shape 17 with its open sides of the U-profiles directed outwards from the cable tray. The figure also discloses the two side bars 11, 12 each connected by its inner side 111, 121 via connections 23 to the respective longitudinal side of the first part 13. The first part 13 is forming a first support surface 52 of a first accommodation 53 for a plurality of cables 54 in the cable tray 10. Each side bar 11, 12 is provided with at least one closed top side 113, 123 and one outer side 112, 122 where the inner side 111, 121 and the outer side 112, 122 have about the same width W and that the side bars 11, 12 each has an open bottom side 55, 56.

[0060] FIG. 6 discloses a top view of the cable tray 10 with the beams in the form of first tray members 14 and second tray members 16. Also the cover member 21 and its mounting hole 22 can be seen in the figure. Other types of attaching means for various devices than mounting holes can be provided in the cover member. As is recognized from this top view is that the U-shaped beams are orientated so that the open side of the beam cannot be seen in a top view of the cable tray. This orientation is important since it will avoid damaging the electrical cables supported by the cable tray. The holes 18 in the cable tray are in this embodiment rectangular. It is also clear from the figure by the curved center lines that cable trays according to the invention can be produced in different suitable lengths. As previously described the connection area 31 between each first tray member 14 and each second tray member 16 are made as part of the members since the tray members are produced from the same sheet of metal. Each top side 113, 123 of the two side bars 11, 12 is formed with an outer top surface 61 and an inner top surface 62 each of which together forms a top angle of the top side of the side bar in the interval of 45-60, preferably =50. This angle can clearly be seen in FIG. 5.

[0061] FIG. 7 discloses in a perspective view from the underside of an end part of the cable tray 10. The first tray members 14 extending in the longitudinally direction 15 of the cable tray 10 and second tray members 16 extending in a transverse direction are seen with their respective open sides facing out from the accommodation of the cable tray. Each side bar 11, 12 have its open sides 55, 56 facing in the same direction as the open sides of the tray members 14, 16. The outer rim 23 and the inner rim 24 of the side bars 11, 12 lies flush with each other thereby defining a resting support surface for handling, mounting and storing the cable tray sections.

[0062] As can be seen from the figures, producing cable trays according to the present invention makes it also possible to cut the cable tray to a desired length near the connection areas of the tray.

[0063] I other embodiments than the one disclosed in the figures the tray members might be arranged with other angles between each other and also towards the longitudinal direction of the cable tray. Furthermore, an end of a second tray member might not only attach to the end of the first tray member as disclosed in the figures but instead attach to a first tray member in the middle thereof and thus providing a different arrangement of holes in a cable tray according to the invention.

[0064] The tray members might not only together define a flat bottom surface but tray members can be curved in order to define tray member ridges or bulbs on the otherwise flat bottom surface, for example to provide side stop means for the cables in the cable tray. The invention also cover embodiments in which the first tray members provides a different bottom level than the second tray members, for example the first tray members defines a higher bottom surface than the second tray members thereby defining ridges holding the electrical cables in firm lateral position in the cable tray.