MODULAR DISTRIBUTION BACK SUPPORT FOR CIRCUIT

BREAKERS

Technical field

[I] The present invention relates to the technical field of electric components, with specific reference to those used for the construction of power distribution panels for industrial use.

Background Art

[2] In industrial power distribution panels is typically used a 380V three-phase electric current with high power applications that can reach and exceed 600A, in order to meet the power requirements of the machineries.

[3] Such power distribution panels comprise a supporting structure shaped like a

cabinet, inside which copper conductive rails carrying the electrical phases of the power line are arranged; various circuit breakers are fixed to the cabinet front panel, and connected to the three copper conductive rails of the power line and, in output, to the appliances to be served.

[4] A copper conductive rails section must be appropriately sized according to the

current flow rate expected, to prevent dangerous overheating.

[5] Suitable type circuit breakers for these uses, are usually combined with a back

support with a significant size, especially in depth.

[6] The back support, made of insulating material, is electrically connected to the corresponding circuit breakers and equipped by connection terminals enabling to realize the various external connections.

[7] For power distribution panels intended to operate with lower current flow rate, up to 100A, a known commercial solution can be used which provides for a plastic duct in which are housed, in parallel, the copper conductive rails of the phases.

[8] The circuit breakers, in this case, can be placed side by side to each other and

suitably connected to the conductive rails by bridge means provided for this purpose.

[9] Each circuit breaker, and any back support, is a system itself, to be connected in parallel to the three-phase current which is carried by the copper conductive rails.

[10] In general, therefore, the structure of the above mentioned power distribution

panels provides, from a constructive point of view, copper conductive rails having a predetermined section area value, circuit breakers, and a set of accessory components suitable for assembling and wiring the circuit breakers and conductive copper rails, so as to ensure the necessary electrical insulation.

[I I] As a result the power distribution panels have a significant total size, which is

often a problem when they have to be placed in a plant.

[12] The increasing size is caused by that the supporting structure shaped like a cabinet is often made larger than necessary, in anticipation of the installation of more circuit breakers; consequently also the copper conductive rails are oversized in section, and having to extend over significant lengths a considerable costs increasing is got, being the copper price notoriously not cheap.

Summary of the invention

[13] The object of the present invention is therefore to propose a modular distribution back support for circuit breakers, used for realizing power distribution panels with high current flow rate, adapted to incorporate conductive rails made of conductive materials carrying the electrical phases of the supply line, which is adapted to support a conventional circuit breaker suitable for the type of the application and which allows to provide the necessary electric connection between the circuit breaker and the conductive rails.

[14] Another object of the invention is to provide a modular back support adapted to be mechanically and electrically coupled to other identical back supports, so as to compose the core of an expandable system in which the power supply rails housed in each back support can be connected to those of the adjacent back supports.

[15] Still another object of the invention aims to provide a modular back support

designed, by appropriate constructive features, for easy assembling and connecting the circuit breaker and for easy coupling and connecting with other back supports, which can be placed either above, below and/or at both sides.

[16] A further object of the invention proposes to carry out a modular back support that thanks to its features allows to save copper during construction of power distribution panels, without limitations for the current flow rate.

[17] Still another object of the invention is to provide a modular back support able to make the circuit breaker removable, without the need of providing additional components that change its configuration.

[18] Another further object of the invention is to obtain a modular back support of regular shape, compact in size and to be produced by not sophisticated constructive methods and equipments, so to minimize costs.

[19] These and other objects are fully achieved by a modular distribution back support for circuit breakers, with the latter of the type intended for high power applications, characterized in that it comprises: a box-like structure made of insulating material with a parallelepiped shape, in which is defined a front face adapted to receive and support the back side of one of said circuit breaker; fixing members able to make a circuit breaker integral with said box-like structure; at least three conductive rails made of conductive material, housed in said box-like structure so as to be electrically isolated from one another, intended to be electrically connected to corresponding phases of an external three phase power supply line; at least three holes, opening at said front face and extending towards the inside of the box-like structure, provided to receive the corresponding plug connectors, protruding from the back face of said circuit breaker and adapted to provide the electric connection between the latter and the above three conductive rails; at least three openings, made starting from each of the four side faces of said box-like structure which are perpendicular to said front face and extended towards the inside of the box-like structure itself, up to make accessible from the outside corresponding portions of said conductive rails, with each set of three openings of a side face aligned with the set of openings made in the opposite side face and with said modular distribution back support adapted to be placed side by side with one or more identical back supports, to form rows both in horizontal and vertical directions, in which the respective front face are coplanar; connecting means, optionally provided between each of said modular back supports and an adjacent one in one or more orthogonal directions, extended through said openings and adapted to define electric bridge connections between the respective conductive rails, so that each distribution back support can be electrically connected in parallel to adjacent ones placed immediately above, below and at both sides.

Brief description of the drawings

[20] The features of the invention will be clear through the following description of a preferred embodiment of the modular distribution back support for circuit breakers in object, in accordance with the claims and thanks to the help of the attached drawings, in which:

• Fig. 1 shows an exploded schematic axonometric view of the modular back support in object;

• Fig. 2 shows a front view of the front face of the back support, on which a circuit breaker has to be placed;

• Fig. 3 shows a side view of Fig. 2, with back support components slightly set apart from each other, to make their identification easier;

• Fig. 4 shows a view similar to Fig. 3, with various components packed on one another;

• Fig. 5 shows a top view of Fig. 2, with components slightly set apart similarly to that illustrated in Fig. 3;

• Fig. 6 shows a view similar to Fig. 5, with various components packed on one another;

• Fig. 7 shows a section of the back support achieved according to the plane II- II of Fig. 2, coupled with a corresponding circuit breaker;

• Fig. 8 shows a schematic front view of the back support, and separated circuit breaker and connection means adapted to connect said back support with other ones;

• Fig. 9 shows a front view with back supports alongside each other, summarizing the expandability of a multiple back supports system.

Description of preferred embodiments

[21] In the above figures is shown with the reference 1, the modular distribution back support for circuit breakers of the invention, as a whole. [22] The modular back support 1 comprises a box-like structure 2, made of insulating material with a parallelepiped shape, in which is defined a front face 2A adapted to receive and support the back side of one of said circuit breakers 100, of a known type and in particular intended for high power applications.

[23] The box-like structure 2 includes fixing members 3 adapted to fasten the circuit breaker 100 to the box-like structure.

[24] In the illustrated example, said fixing members 3 comprise a set of fixing holes 30, perpendicular to the front face 2A with appropriate diameter and distance, adapted to be engaged with interference by self-tapping screws passing through the circuit breaker 100 and protruding from the back of said circuit breaker.

[25] At least three conductive rails 41, 42, 43 made of conductive material, preferably copper, are housed in said box-like structure 2 so as to be electrically isolated from one another and intended to be electrically connected to corresponding phases of an external three phase power supply line, not shown.

[26] According to a preferred embodiment, the aforementioned three conductive rails

41, 42, 43 are offset in the horizontal dimension of said box-like structure 2, as well as offset in the depth dimension of the latter.

[27] In addition, each of the conductive rails 41, 42, 43 comprises a main branch 41 A,

42A, 43 A, extending vertically, so as to fill almost entirely a corresponding vertical housing of said box-like structure 2, and at least one secondary branch 41B, 42B, 43B, perpendicular to the main one, contained in the horizontal dimension of said box-like structure 2 and offset in the vertical dimension to the secondary branches of the conductive rails corresponding to the remaining phases of said three-phase line.

[28] In the side conductive rails 41, 43, the respective secondary branch 41B, 43B is single and extends towards the inside of the box-like structure 2, while the central conductive rail 42 has a secondary branch 42B which extends bilaterally, and symmetrically, with respect to that main one 42A (Fig. 1).

[29] At least three holes 21, 22, 23 opening at the front face 2A , and extending towards the inside of the box-like structure 2 are provided to receive the corresponding plug connectors 101, 102, 103, protruding from said back face of a circuit breaker 100 and adapted to provide the electric connection between the latter and the aforementioned three conductive rails 41, 42, 43.

[30] In the main branch 41A, 42A, 43A of each of said conductive rails 41, 42, 43, is provided a connection hole 41C, 42C, 43C, coaxial to the corresponding hole 21, 22, 23 provided for the introduction of the respective plug connector 101, 102, 103.

[31] The connection holes 41C, 42C, 43C have an appropriate diameter to be in contact with the corresponding portions of said plug connectors 101, 102, 103, in order to ensure the electric connection (Fig. 7).

[32] According to the invention, for each of the phases of the aforementioned three- phase power supply line is provided a single conductive rail 41, 42, 43, as described above, or, as shown in the attached figures, a pair of each of them, identical and overlapping, with insulating separators 41S, 42S, 43S interposed therebetween, and obtained in the aforementioned box-like structure 2, with the conductive rails of each pair intended to be electrically connected.

[33] In this embodiment, the plug connectors 101, 102, 103 are sufficient in length to engage both the connection holes 41C, 42C, 43C of the corresponding pair of conductive rails 41, 42, 43.

[34] In each of the four side faces 2B, 2C, 2D, 2E of the aforementioned box-like

structure 2 which are perpendicular to said front face 2A, are provided at least three openings 24, 25, 26 extended toward the inside of the structure 2 thereof, up to make accessible from the outside corresponding portions of said conductive rails 41, 42, 43.

[35] In the upper face 2B and lower face 2D the portions of the conductive rails 41, 42,

43 are made accessible at the respective main branches 41 A, 42A, 43 A, while in the right side face 2C and left side face 2E are made accessible the corresponding secondary branches 41B, 42B, 43B.

[36] Each set of three openings 24, 25, 26 of a side face 2B, 2C, 2D, 2E is aligned with the set of openings in the opposite side face, for example those of the upper side face 2B with those of the lower side face 2D and those of the right side face 2C with those of the left side face 2E.

[37] Due to this constructive solution, the modular back support 1 is adapted to be

placed side by side with the said side faces 2B, 2C, 2D, 2E, with one or more identical back supports 1, to form rows both in horizontal and vertical directions, in which the respective front face 2A are coplanar and, at the same time, the openings 24, 25, 26 of the side faces placed side by side reciprocally are aligned.

[38] By the use of connecting means 5, between each of said modular back support 1 and the other immediately adjacent in one or more orthogonal directions, electric bridge connection between the respective conductive rails 41, 42, 43 can be defined, so that each distribution back support 1 can be electrically connected in parallel to adjacent ones placed immediately above, below and at both sides.

[39] Said connecting means 5 are composed, for example, of plates of appropriate

length, made of conductive material, preferably copper, inserted in the corresponding openings 24, 25, 26 of two placed side by side faces and extended through said faces to connect the corresponding conductive rails 41, 42, 43.

[40] The plates 5 are appropriately punched at the ends, so that after their insertion into the openings 24, 25, 26, the holes are coaxial with wiring holes 4 IP, 42P, 43P provided in the conductive rails 41, 42, 43, both if the latter are single and double.

[41] Plates holes 5 and wiring holes 41P, 42P, 43P are adapted to be engaged by

fastening elements, for example screw, not shown in detail, introduced through suitable holes provided in the box-like structure 2.

[42] In a preferred embodiment, referred to in the attached figures, the box- like structure 2 is composed of a plurality of layers packed on one another, for example seven in number 201, 202, 203, 204, 205, 206, 207 starting from the one defining said front face 2A (see in particular Figs. 1, 3 and 5).

[43] The layers 201, 202, 203, 204, 205, 206, 207 are rigidly coupled, for example by screw means not illustrated in detail, and each of them is shaped to define:

• said fixing holes 3;

• at least one of the above three holes 21, 22, 23;

• at least part of the housings in which are housed said conductive rails 41 42, 43;

• at least a part of the aforementioned openings 24, 25, 26.

[44] In accordance with the embodiment in which the conductive rails 41,42, 43 are double, they are interposed with said layers, so that the layers also act as the mentioned insulating separators 4 IS, 42S, 43 S: more in particular, the layer 202 realizes the insulating separator 4 IS between the pair of conductive rails 41, the layer 204 realizes the insulating separator 42S between the pair of conductive rails 42 while the layer 206 realizes the insulating separator 43S between the pair of conductive rails 43 (Figs. 1, 3, 4, 5).

[45] To visually exemplify the modular arrangements offered by the back support 1 in object, in Fig. 8 are shown, separately, in addition to one of said back supports 1, a circuit breaker 100 and some plates 5.

[46] In Fig. 9, instead, the elements of Fig. 8 are shown joined, ready to be mechanically and electrically coupled to other identical back supports 1, so as to compose the core of an expandable system in which the power supply conductive rails 41, 42, 43 housed in each back support 1 can be connected to those of the adjacent back supports 1.

[47] According to what above described, in particular for skilled in the art, the advantageous features of the present invention are evident, and enable to produce power distribution panels, even intended for high power applications, in a completely new way compared to the constructive criteria adopted with the prior art solutions, implementing a saving in overall size of the distribution panel.

[48] Copper conductive rails carrying the electrical phases of the supply line are housed inside the modular back support in object so as to not have to arrange the rails externally, with evident advantages.

[49] The modular back support, as described, is able for supporting a conventional circuit breaker, adapted to provide the electric connection between the circuit breaker itself and the conductive rails and to allow couplings with other back supports and other circuit breakers only having to arrange connecting plates, with unlimited expansion capability.

[50] The modular back support has, advantageously, all the constructive features

enabling to mount and connect easily the circuit breaker and to couple and connect easily the modular back support with other back supports arranged above, below and/ or at both sides.

[51] Thanks in that the back support is compact in size and conductive rails are housed inside the back support and back supports can be modularly coupled in reduced spaces, the total weight of the copper conductive rails is considerably lower, being equal the current flow rate and the power distribution panel framework, with the obvious benefits in costs saving.

[52] In addition to the specific features above mentioned, the modular back support of the present invention provides an additional interesting plus for which a brief mention to the prior art is needed: the mentioned circuit breakers can be mounted on conventional back supports in a fixed, removable or extractable manner.

[53] It is a removable circuit breaker if it can be set apert from the back support, both functionally and physically, by unscrewing the fixing screws fastening the first to the second; it is a extractable circuit breaker if for its removal, elements coupled as a sled are used, a part of which are joined to the back support fixed part and a part to the circuit breaker.

[54] To set up a prior art back support able to make the circuit breaker removable or extractable, it should be provided with suitable accessory components also relating to electric connection elements, with the resulting costs increasing; in the proposed modular back support, instead, thanks to the connection achieved by plug connectors, the removability and extractability are obtained directly by the described structure, without additional components, and, therefore, without the cost increases.

[55] Another feature of the invention to be highlighted is the regular shape and compact size of the modular back support, which can be produced by not sophisticated constructive methods and equipments, in particular the embodiment composed of several layers packed on one another.

[56] However it is understood that the above is described as an example and it's not limiting, and therefore, any changes of detail necessary for technical and / or functional reasons have to be considered by now within the scope of protection of the inventive idea as claimed below.