FR2914117A1 - Vertical column for metallic framing housing of e.g. IP30 modular cabinet, has reinforcement system welded on branches over length of system to locally close column, where length of system is lesser than one third of length of column - Google Patents

Abstract

The column (4) has a U shaped metallic section with lateral branches parallel and longitudinally extended on length of the column, where the length of the column is greater than 1.8 meters. The section is made of a folded steel sheet and has a thickness lesser than 2 millimeters. The branches are orthogonal to a connection side (26) between the branches. A reinforcement system is welded on the braches of the section over the length of the reinforcement system to locally close the column, where the length of the reinforcement system is lesser than one third of the length of the column.

Description

OPENED REINFORCED AMOUNT FOR ELECTRICAL CABINET TECHNICAL DOMAIN

  The invention relates to electrical cabinets made from framing frames. According to the invention, the shape of the uprights is optimized so as to ensure a compromise between warp resistance, ease of manufacture and minimization of the amount of material required. The invention thus relates to an upright cabinet comprising an open folded steel section, associated locally with one or more reinforcements closing the section of the upright. The invention also relates to a cabinet frame comprising four vertical uprights and a cabinet comprising closure panels associated with a frame, or several frames secured together.

STATE OF THE ART

  The electrical cabinets are conventionally made from a frame frame 20 to which are associated closure panels and attachment systems to accommodate electrical distribution and circuit protection elements. The location of the different elements can not be fully rationalized with regard to the distribution of the masses, and the constraints on the frame are not uniformly distributed. In view of the asymmetrical forces which it undergoes, the frame must therefore be made with a sufficient rigidity to avoid any warping and / or torsion and / or bending, in particular vertical uprights.

  From a mechanical point of view, the optimum solution with respect to the rigidity and torsional strength of the frame components is the closed section. In fact, some cabinets are made with tubular uprights; this solution makes it possible to limit the sheet thickness to withstand the constraints relating to the use of the cabinet; in addition, this small thickness does not reduce the perception of rigidity of the frame. However, this type of design is expensive to manufacture, with dedicated welding equipment.

  More conventionally, the cabinets are frequently constructed from open-profile posts: see FR 2,615,684. Mechanically, the torsional resistance of a section section that is open relative to that of the same section section is much lower, with in particular a factor greater than one hundred between a closed square and the U resulting from the deletion of one of the sides of the square. In order to meet the requirements for holding the cabinet to the constraints of placing electrical elements, the thickness of the profile of the upright must therefore be substantially increased, which consequently increases the material cost, as well as the difficulty of handling. components, which are heavy.

  It has been proposed various amounts of geometries, for example in WO 96/14731 to increase rigidity while keeping the structure open and optimizing the amount of material used. These solutions, however, are very complex to implement, including important constraints during folding; moreover, the perception of rigidity remains weak.

  DISCLOSURE OF THE INVENTION Among other advantages, the invention aims to overcome the drawbacks of existing solutions, and to provide sufficient rigidity to the uprights of an electrical cabinet while simplifying their manufacture and minimizing the amount of material to achieve them.

  More generally, the invention relates to an upright for an electrical cabinet, for example a section of length equal to or greater than 1.8 or 2 m, generally U-shaped with three sides preferably substantially equal, for example between 35 and 40 mm side, folded steel thickness preferably less than 2 mm, for example 1.5 mm, wherein a reinforcing system is welded to locally close the section of the amount. The reinforcing system comprises at least one reinforcement, and preferably three, in the general form of a closure plate, welded on its edges to the branches of the U; the length of the reinforcing system, that is to say the sum of the length of each reinforcement, is less than or equal to one third of the length of the profile, preferably of the order of one eighth or even one tenth.

  The closure may be complete or partial, with more or less deep insertion of each reinforcement between the branches of the U so as to leave or not a portion of the sides of the free profile; the location of the reinforcements relative to the bottom of the U can be optimized by extending the closure plates by wings that bear against the bottom of the profile. Each reinforcement is advantageously made of folded sheet with a thickness less than or equal to that of the upright, for example 1.2 mm.

  The reinforcement system comprises a reinforcement located substantially in the center of the amount. Advantageously, this reinforcement comprises a thread, for example disposed on an extension of the reinforcement pressing against the bottom of the U of the upright, which can be used to secure a handle.

  Advantageously, the reinforcing system comprises two other reinforcements located symmetrically with respect to the central reinforcement, for example substantially at mid-height of the upright, that is to say at the usual fastening points between frames. These reinforcements may be identical to the central reinforcement, but advantageously, they comprise an anti-rotation system comprising an orthogonal portion juxtaposed to a branch of the profile and have no door fastening thread.

  To allow so-called IP54 associations with the same amounts according to the invention, advantageously, the section comprises, in orthogonal section to its length, a shoulder on one of the branches, intended to be located towards the outside of the frame. The U thus comprises a first branch in which can be distinguished a first portion at the open end of the U and a second portion at the bottom of the U. The first and second parts are parallel to the second branch of the U, offset by the shoulder: the distance between the two branches of the U is greater than the bottom level of the U with respect to the open end. Preferably the shoulder is of the order of the thickness of the profile and allows the passage of an anti-rotation system pressing against the U branch without increasing its overall size. When associating with another component, side panel or upright of another frame, it is possible to position a seal at the first part of the second branch, joint squeezed during assembly, for example by screwing, said component.

  The invention also relates to a frame made from four uprights as previously defined, secured together at each end by an upper frame and a lower frame of four sides each. The lateral sides of the frames are delimited by branches of the U, in particular the branches provided with shoulders, and the open end of the U is directed towards the inside of the frame.

  The frame according to the invention can be associated with another frame, forming an assembly advantageously made by screwing at the reinforcement system, in particular at two reinforcements with anti-rotation system. A seal can be inserted on the first part of the upright when the profile has a shoulder on a branch to achieve a seal at this level.

  The invention finally relates to an electrical cabinet comprising closure panels on such a frame or such a set of frames. Again, the side panels can be put in place in the presence of a seal at the shoulder to seal the cabinet.

  BRIEF DESCRIPTION OF THE FIGURES Other advantages and features will become more clearly apparent from the following description of particular embodiments of the invention, given by way of illustration and in no way limiting, represented in the appended figures.

  FIGS. 1A and 1B show an exemplary embodiment of a frame according to the invention.

  FIGS. 2A and 2B schematize the reinforcement principle for an amount according to the invention.

  Figure 3 shows the establishment of a side panel to make a cabinet called IP54 according to the invention.

  Figures 4A and 4B show a central reinforcement for a preferred embodiment of the invention.

  Figures 5A and 5B show another reinforcement for a preferred embodiment of the invention.

  Figure 6 illustrates the assembly between two amounts to produce a set of frames according to a preferred embodiment of the invention.

  DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT The description will use, for the sake of clarity and simplification, localization terms, such as vertical or inferior or lateral, relative to the usual position of an electrical cabinet in use; it is understood that these terms are in no way limiting.

  According to a preferred embodiment illustrated in FIG. 1A, the cabinets 1 according to the invention are manufactured from metal frames 2 comprising four vertical uprights 4, held at their ends by lower sides 6, 8 and upper sides, which are for example secured by screws 10 and / or welded to form a frame (see also Figure 1B). Preferably, the frames 2 according to the invention are standardized and in particular of standard size, for example a height of more than 1800 mm, in particular for example 1990 mm, a width of 600 mm and a depth of 400 or 600 mm; according to the required dimensions, the cabinets 1 are manufactured from a frame or several frames secured side by side, this skeleton being covered in particular by two side panels 12 and two panels 14 front and rear, one of these at least being hinged to form a door. For this purpose, the various elements 4, 6, 8 of the frame 2 are provided with mounting orifices 16.

  The invention relates mainly to the vertical uprights 4 of the frames 2 - the other parts 6, 8 of the frame can be made as usual, or to take the same general shape as the profiles of the uprights 4. An embodiment is illustrated in Figure 1B, wherein the lateral lower side 8 is the same geometry as the vertical upright 4 to which it is welded, and the lower front side 6 is of another design, screwed on the assembly 4, 8. Advantageously to increase the rigidity, reinforcing pieces 18 are added to the upright 4 and / or a side 8 of the lower frame to the connection end: the local thickness of the profile 4, 8 can be doubled by a square 18 which is welded to it.

  According to the invention, as shown in FIG. 2A, the uprights 4 are made from metal profiles 20 of generally U-shaped shape, in particular from a steel sheet, such as folded DCO1. The profile 20 comprises two branches 22, 24 substantially parallel and extending longitudinally along the length L of the upright 4, the branches 22, 24 being connected on one side 26 by the same sheet and open on the other side; the open end 28 of the U (Figure 2B) is intended to be positioned towards the inside of the cabinet 1, towards the front and rear faces 14, that is to say that the lateral faces 12 of the frame 2 are delimited by branches 22, 24 of the U. The sides 22, 24, 26 of the U are pierced by the orifices 16 defined above for the subsequent connections between them, with the frames of the frame 2 (Figure 1B), with the panels of the cabinet 1, as well as any accessories such handle or hinge. In addition, the branch 22 intended to be placed inside the cabinet 1 is pierced with holes 30 for the subsequent positioning of the mounting systems of the electrical elements; for example, two rows 301, 302 of regularly distributed holes 30 can be drilled over almost the entire length L of the section 20.

  According to a preferred embodiment, the upright 4 is included in a 40 mm square tube; in particular, the U comprises three sides 22, 24, 26 with a length 1 of approximately 37.5 mm. Advantageously, the branch 24 of the U intended to be secured to a side wall 12 of the cabinet 1 comprises a shoulder 32 as illustrated in FIG. 2B: the branch 24 comprises a first portion 34 of branch at the open end 28 of the U and a second portion 36 at the connecting side 26 of the U, the first and second parts 34, 36 being parallel to each other and to the second leg 22 of the U, the distance to the open end 28 between the second branch 22 and the first part 34 being smaller than the distance 1 between the second branch 22 and the first part 36. Preferably, the shoulder 32 is of the order of the thickness e of the sheet of the profile 20.

  This embodiment makes it possible, with the same upright 4, to securely fasten the side panel 12. As shown in FIG. 3, it is possible, prior to mounting the panel 12, to insert a gasket 38 on the first branch 34 and adjacent to the shoulder 32. During the establishment of the side panel 12, which bears on the second branch 36, and its tightening on the first branch 34 (arrow), by screwing for example, the seal 38 is compressed : Protection against splashing liquids and dust (called IP54) is provided between the edge 24 of the profile 20 and the panel 12.

  Given the forces experienced by the frame 2 of the cabinet 1 in use and especially during transport, for example by the stress generated by the stress of 300 kg generated by the busbar and the equipment fixed on the uprights 4, this Kind of upright architecture 4 would require e sheet metal thicknesses greater than 2.5 or 3 mm to avoid deformation in use. According to the invention and as shown diagrammatically in FIG. 2, to increase the torsional strength of the upright 4 while reducing the quantity of steel required, the upright 4 is of locally closed section by means of a reinforcement system. 40, so that the buckling of the amount 4 at this level is minimized; at the same time, the slenderness of the portion portions of open section, located between the portions closed by the reinforcement system 40 and therefore shorter, is limited.

  The reinforcing system 40 comprises in particular a closure plate 42 of length d and width greater than or equal to that of the open end 28 of the profile 20 (1 3e for FIG. 2B, that is to say that the width of the closing plate 42 is less than or equal to the width 1 of the section 20) so as to be welded on each of its branches 22, 24 in order to take up the longitudinal stress in shear and transmit it from one to the other . The closure plate 42 may be provided with through orifices 44 allowing in particular an anti-corrosion protection to penetrate into the closed section; it is welded on each longitudinal edge 46, over a portion of its length sufficient for stress recovery. The reinforcing system may be composed of a plurality of closure plates 42a, 422 distributed along the profile 20.

  To achieve a pre-defined buckling resistance of the upright 4, the length d (= Ed;) of the portion closed by the reinforcement system 40 depends on the section (1 x 1) of the profile 20 as well as the location both vertical and horizontal closure plates 40; relative to the amount 4. Indeed, it is possible to completely close the section 20 by a plate 42, or it may be preferred to leave one end of the branches 22, 24 free and close the bottom of the section 20 by a plate 422, for example to leave a row 30 of mounting holes accessible for mounting systems. The torsional strength of the upright 4 depends on the closed volume: at the same height position on the upright 4 of a closure means 42, to obtain the same rigidity, its length d is increased when its insertion at depth p decreases.

  Thus, in the previous embodiment (1 = 37.5 mm, L = 2 m, shoulder 32 of e), the plate 42a positioned at the end of the branches 22, 24 of the U, can be of a length from 15% shorter than a plate 42, pressed at a depth p of 16.5 mm.

  To facilitate its horizontal positioning and increase manufacturing tolerance, it is preferred that each closure plate 42 be associated with substantially orthogonal wings 48, coming into contact with the closed side 26 of the profile 10, so that the plate 42 is positioned in depth in the U in an easy and reproducible way. In order to facilitate the welding of the plate 42 on the branches 22, 24 of the U, the positioning wings 48 are advantageously located in the width direction, so that the plate edges 46 are welded directly to the section 20.

  Advantageously, the reinforcing means 40 are made of folded sheet metal, and the thickness of the closure plate 42 is less than or equal to the thickness e of the profile 20; preferably, it is the same material as for the profile 20 to facilitate welding.

  In particular, the various elements 20, 40, or even 6, 8 of the frame 2 can be manufactured from the same supply.

  The upright portions 4 comprising the reinforcement system 40 are very rigid in torsion; in addition, the portions of open section adjacent to these rigid portions benefit and their warpage is limited. It is thus preferred that the reinforcement system 40 comprises several closure means 42; distributed along the amount 4 to optimize these effects; in particular, it has been shown that three reinforcements are advantageous. Thus, at equal depth p, the cumulative length of three homogeneously distributed plates may be equal to one third of the length d of a single central reinforcement for the same results (Id, <d / 3), which decreases by as much the amount of material needed.

  By way of example, to achieve the invention and obtain the same warping resistance of a profile section 37.5 x 37.5 cm and length 2 m, one can therefore: either weld on d = 600 mm a plate 42, flush with the branches 22, 24 of the U and at the center of the profile 20; to weld, each on d = 64 mm, three plates 42, flush with the branches 22, 24 of the U, respectively quarter, center and three quarters of the profile 20; to weld, each on d = 75 mm, three plates 422 at mid-height of the branches 22, 24 of the U, respectively quarter, center and three-quarters of the profile 20.

  To achieve the objectives of the invention, the reinforcing system 40 comprises a reinforcement 50 placed at half height of the upright 4, the position being given by the middle of its closure plate 52. Advantageously, as illustrated in FIGS. 4A and 4B, this central reinforcement 50 can also be used when placing the handle elements of a door of the cabinet 1. For this purpose, it may be advantageous to extend at least one of the positioning wings 54 by a return 56 provided with a threaded orifice 58: the thickness of the connecting side 26 of the profile 20 is increased by the reinforcement 50 which can serve as a support for the lock. In particular, as shown in FIG. 4A, the reinforcement 50 is symmetrical, in the form of a closed C-shape, with two threaded holes 58 for fastening the bolt stop of the handle on returns 56 of the C which cooperate with an orifice 16 on the bottom 26 of the profile, and a free passage 60 on the reinforcing plate 52. Preferably, the weld beads 66 are placed at the mid-depth of the bottom of the section 20.

  Furthermore, FIG. 4A has a central recess 62 on each longitudinal side 64 of the closure plate 52. In fact, the shear flow must be able to be transmitted from one branch to the other through the reinforcement, and it is preferred to proceed by four weld beads 66 at the four corners of the plate 52: it is not necessary to weld the reinforcement 50 over its entire length; the recesses 62, in addition to indicating the welding points 66, participate in the penetration of an anti-corrosion paint while reducing the assembly 50.

  Although, in order to reduce the number of industrial references, it is preferable for all the components of the reinforcement system 40 to be identical and to use the preceding example without association with a handle, it may be advantageous for reinforcements to have a geometry different from the central reinforcement 50, for example lightened by the absence of returns 56 provided with threaded holes 58; in particular, it is then possible to provide them with elements providing other advantages. In particular, a reinforcement 70, also made of folded sheet metal, as illustrated in FIGS. 5A and 5B may be recommended. The reinforcement 70 comprises a closure plate 72 provided with lateral wings 74; having no support function, these positioning wings 74 can be reduced in size.

  To increase the resistance to warping, the reinforcement 70 is provided on one of its edges at least with means 76 countering the rotation of the plate 72 relative to the amount 4; the other edge 78 of plate 72, intended to be welded to the inner branch 22 of the section 20, can remain straight, and be welded along its length, or in two cords. In particular, the anti-rotation means comprise an extension of the edge concerned by a portion 76 orthogonal to the plate 72 and coming into contact with the outer branch 24 of the section 20 to be welded therein; preferably, to resist crushing during an association between two studs under the screw stress (see below), this orthogonal portion 76 is directed towards the open end 28 of the U and is welded at its end, the positioning wings 74 being of less depth than the length of the branches 22, 24.

  In particular, when the profile 20 comprises the shoulder 32 on its outer lateral branch 24, it is advantageous, in particular for the associations between two uprights 4 in which the screws induce a pinch movement (see FIG. 6), that the orthogonal portion holding 76 passes through the first portion 34 of the branch through an orifice 80: the two parts 76 come into contact and prohibit deformation. It should be noted that the overall thickness is not changed.

  As mentioned above, the frames 2 according to the invention can be associated with each other so as to increase the size of the resulting cabinet: two uprights 4 to 4, are positioned side by side and secured together by appropriate means, and preferably in two places along the length. It is advantageous that reinforcements 70 are positioned at these lateral associations between two uprights 4: in fact, especially when they are provided with anti-rotation means 76, the reinforcements 70 also prevent crushing of the uprights 4. The presence of the reinforcements 70 thus allows the use of a basic means, for example a simple screw, to achieve the association.

  Thus, as illustrated in FIG. 6, according to a preferred embodiment, two posts 4, 42 are juxtaposed by their branch 24, 242 comprising the shoulders 32; a screw 90 passes through the four branches by orifices 16 provided for this purpose, the screw 90 being positioned between the two contact areas 76, 78 between each upright 4 and each reinforcement 70, thereby preventing the torsion thereof. The proximity and the shape of the reinforcement 70 makes it possible to prevent the branches 22, 24 of the profiles from being crushed, the flow of the tightening forces of the screw passing in compression in the reinforcements 70 rather than in flexion in the said branches of the U of the upright .

  In addition, if the profile has the shoulder 32 as described above, it is possible with the same profile to make a cabinet from a combination of so-called IP54 frames, by inserting a seal 92 along the branch 24 of the U, seal that will be crushed in a natural way when tightening the two uprights 4.

  The solidarity between amounts 4; is usually provided at specific locations of the amount, especially at a quarter and three quarters of the height. For reasons of ease of storage and optimization of production costs, it is advantageous that all the amounts according to the invention are manufactured with the same characteristics and therefore with the reinforcements 50, 70 welded in the same places.

  Advantageously, for the preferred embodiment presented above, a central reinforcement 50 of length 75 mm as illustrated in FIG. 4A is fixed at 1000 mm from the bottom of the profile, with two reinforcements 70 of 75 mm as illustrated in FIG. 5B to 450 mm on each side (distance taken in the center of the reinforcement), with reinforcements 50, 70 inserted at 16.5 mm into the profile 20.

  The presence of the reinforcement system 40 according to the invention therefore allows the thickness of the profiles 20, which is the base of the uprights 4, to be correspondingly reduced, with the corresponding material gains: in particular, at comparable rigidity, the welding of a plate 42 reduces by about 30% the thickness e of the sheet for the preferred embodiment compared to the same profile without reinforcement. Thus, in particular, by inserting the three reinforcements 50, 70 with a thickness of 1.5 or 1.2 mm as described above, it is possible to produce with a profile of e = 1.5 mm, in any case less than 2 mm. , a cabinet 1 of technical characteristics suitable for everyday use. In fact, compared to a range whose amounts are closed along their length with a thickness of the order of 1.2 mm, the same amount of material is used for the frame according to the invention, for the same properties.

  The solution according to the invention, which furthermore gives a good perception of rigidity, remains easy to manufacture: the shape of the profile is basic, easy to make and the welds relate only to discrete reinforcement elements on reduced dimensions, that it is possible to carry out without dedicated tools. Industrial investment for this type of cabinet is reduced, while retaining the option to achieve, with the same industrial references, so-called IP30 or IP54 cabinets, possibly including several units.

  Thus, although geometry a priori very simple, the amounts according to the invention allow a complete modularity, filling without unnecessary complication of their manufacture, the different functions: support side panels, horizontal and vertical busbar supports, support functional units, possibility of side by side association, ...

Claims (14)

  An upright (4) for an electrical cabinet (1) comprising a profile (20) of a first length (L) made of substantially U-shaped sheet metal, with two lateral branches (22, 24) substantially orthogonal to a connecting side ( 26) between the branches (22, 24) and open at the other end (28), characterized by a reinforcing system (40) welded to the branches of the profile (20) on a second length so as to locally close the amount (4), the length (d) of the reinforcement system (40) being less than one third, of the first length (L) of the upright (4).   2. The amount of claim 1 wherein the sheet of the profile (20) is of thickness (e) less than 2 mm, the first length (L) is greater than 1.8 m, and the two branches (22, 24 ) of the profile being substantially of the same size.   3. Upright according to one of claims 1 or 2 wherein the reinforcing system (40) comprises a plate (42) welded on its edges (46) substantially in the middle of the branches (22, 24) of the U relative to the side link (26), so that the upright (4) is closed with two wings protruding from the closed part.   4. Upright according to one of claims 1 to 3 wherein the reinforcing system (40) comprises a plurality of reinforcements welded between the branches of the profile (20) and on each branch (22, 24) of the U so as to close locally amount (4) leaving open sections between said reinforcements.   5. Upright according to claim 4 wherein at least one reinforcement (70) comprises a closure plate (72) substantially parallel to the connecting side (26) and an anti-rotation system (76) resting on a branch (24). profile (20).   6. Upright according to one of claims 4 or 5 wherein a reinforcement (50) comprises a thread (56) for securing the bolt stop system of a handle. 13   7. Amount according to one of claims 4 to 6 wherein a reinforcement (50) is located substantially in the center of the upright (4), and two other reinforcements (70) are symmetrical with respect to the central reinforcement (50).   8. Amount according to one of claims 4 to 7 comprising three reinforcements (50, 70) whose sum of lengths is less than one-eighth of the first length (L).   9. Amount according to one of claims 1 to 8 wherein in section orthogonal to the length, a first leg (24) of the U comprises a first portion (34) at the open end (28) and a second portion (36) at the connecting side (26), the first and second portions (34, 36) being substantially parallel to the second leg of the U (22), the distance between the second leg (22) and the first leg (34) being less than the distance between the second leg (22) and the second portion (36).   10. Frame (2) of an electrical cabinet (1) comprising four uprights (4) according to one of claims 1 to 9 parallel, secured at each end by an upper frame and a lower frame, the open parts (28) U of each upright (4) being directed inwardly of the frame (2) face to face so that the legs of the U (22, 24) are parallel to the side faces (12) of the frame (2).   11. Set of frames comprising at least two frames (2) according to claim 10 wherein each of the frames comprises at least two uprights (41, 42) according to claim 9 forming a side face (12), said amounts being coupled by means of screw (90) solidarisant said frames.   12. An assembly according to claim 11 comprising a seal (92) between the first portions (34) of the legs of the uprights (41, 42) coupled so that the seal (92) is crushed by the screws (90) and forms a coupling étanche.30   13. Electrical cabinet comprising a frame according to claim 10 or a set of frames according to one of claims 11 or 12 on which are mounted two side panels (12) and two front panels (14) including a door.   The cabinet of claim 13 wherein all the posts (4) are in accordance with claim 9 and including a seal (38) between the first portions (34) of the legs of the mated posts (4) so that the seal (38) ) is crushed by side panels (12).