VENTILATION BLOCK FOR ELECTRICAL SWITCH CABINET

Description

[0001] The present invention relates to a ventilation unit for an electrical enclosure such as, for example, an electrical cabinet.

[0002] The invention also relates to an electrical installation comprising an electrical enclosure on which several ventilation blocks in accordance with the invention are positioned. Etat de la technique

[0003] Managing the temperature inside an electrical enclosure, such as an electrical cabinet or switchboard, is a recurring issue. The devices inside the electrical cabinet tend to heat up, and it is therefore necessary to maintain the temperature inside the cabinet below a certain threshold, otherwise there is a risk of damaging the devices. To address this constraint, it is common to use a ventilation system to create an airflow through the volume of the electrical cabinet by drawing in air from outside and exhausting the hot air inside the cabinet to the outside.

[0004] Known ventilation systems are commonly placed on the top wall of the electrical cabinet. They include an inlet connected to the internal volume of the cabinet to receive an outgoing air flow, an air outlet, and a fan placed between the inlet and the outlet to drive the air flow from the inlet to the outlet.

[0005] In general, the ventilation system associated with an electrical cabinet is formed by a block positioned on the upper wall of the electrical cabinet. This block is most often designed to meet a single protection index (IP) only, limiting its use. In addition, it is very often imposing and occupies the entire upper wall of the cabinet, which offers no possibility of easily adapting the air flow to be generated through the electrical cabinet, for example in the event of changes to the electrical equipment housed in the electrical cabinet, nor any possibility of redundancy between several ventilation blocks associated with the same electrical cabinet.

[0006] WO 2014 / 035661 A1 thus discloses a ventilation unit comprising a fan and a housing in the shape of a straight block. A base of the housing is closed at the top by a cover and is crossed at its base by an opening around which a seat accommodates the fan. WO 2014 / 035661 A1 envisages that, on each side face of its housing, the base comprises a grille allowing the circulation of air through it.

[0007] EP 1 878 484 A1 discloses a ventilation unit comprising a fan and a housing including a single side grille, on the outer face of which is attached an interchangeable filter. The filter is held in place against the grille by a grille which, by pivoting, gives access to the filter for changing it, without the need to use a tool.

[0008] WO 2015 / 127989 A1 discloses a household appliance, such as a washing machine, a dishwasher, a refrigerator. The interior of this household appliance is connected to the outside through a grille device through which air is driven by a fan arranged inside the household appliance. The grille device comprises two grilles which are connected to each other by a hinge. In use, the two grilles are folded down and held permanently against each other. Prior to being put into service, the two grilles are manufactured by molding in a non-functional state of the grille device, where these two grilles are juxtaposed edge to edge in the same geometric plane.

[0009] The aim of the invention is to propose a ventilation unit intended to be used for an electrical enclosure, which can in particular offer several protection indices without having to be replaced and without complex modification of its architecture. The ventilation unit can easily be combined with one or more other similar ventilation units to achieve the objectives defined above. Exposé de l'invention

[0010] This aim is achieved by a ventilation block for an electrical enclosure, as defined in claim 1.

[0011] Features of this ventilation unit are specified in claims 2 to 7.

[0012] The invention also relates to an electrical installation as defined in claim 8.

[0013] Particular features of this installation are specified in claims 9 and 10. Brève description des figures

[0014] Other characteristics and advantages will appear in the detailed description which follows, given with reference to the attached drawings in which: [ Fig.1 ] There figure 1 represents a ventilation block in accordance with the invention. Fig.2 ] There figure 2 represents the ventilation block according to the invention, in exploded view. Fig.3 ] [ Fig.4 ] [ Fig.5 ] THE figures 3, 4 And 5 represent different configurations of the ventilation unit according to the invention. Fig.6A ] [ Fig.6B ] [ Fig.6C ] [ Fig.6D ] [ Fig.6E ] THE figures 6A à 6E illustrate, by means of sectional views, different configurations taken by the ventilation unit of the invention. Fig.7 ] [ Fig.8 ] [ Fig.9 ] [ Fig.10 ] THE figures 7 à 10 illustrate the principle of juxtaposition of several ventilation blocks in accordance with the invention. Fig.11 ] There figure 11 represents an airflow management system used in association with two ventilation blocks in accordance with the invention. Fig.12A ] [ Fig.12B ] THE figures 12A And 12B illustrate the operating principle of the airflow management system according to the invention. Description détaillée d'au moins un mode de réalisation

[0015] The invention relates to a ventilation system which is adaptable to an electrical enclosure. By electrical enclosure is meant an electrical cabinet, an electrical box or the like. In the remainder of the description and in the drawings, the electrical enclosure will be considered to be an electrical cabinet 1.

[0016] In the remainder of the description, the terms "upper", "lower" or equivalent are to be taken into account in relation to a vertical axis (A) shown in the attached figures.

[0017] In a non-limiting manner, an electrical cabinet 1 may comprise a lower wall 10, an upper wall 11 and four side walls 12 opposite each other in pairs. Its walls delimit a first internal volume V1 in which electrical devices are placed. In the electrical cabinet, the electrical devices 13 may be mounted on supports, such as suitable uprights and rails 14. The electrical cabinet 1 comprises a grille 15 allowing its internal volume to exchange air with the outside. figures 12A And 12B allow to clearly show the characteristics of such an electrical cabinet.

[0018] Electrical cabinet 1 may be made of a metallic material.

[0019] The ventilation system comprises one or more ventilation blocks 5 (also referenced 5.1, 5.2, 5.3, 5.4 in the attached figures when several blocks are present), each ventilation block 5 being placed on the upper wall 11 of the electrical cabinet 1 and comprises an air inlet in communication with the internal volume V1 of the electrical cabinet. Conventionally, in operation, each ventilation block 5 creates an air flow through the volume of the cabinet 1, by taking air from the outside through the grille 15 and by rejecting the hot air towards the outside. The grille 15 is advantageously placed at the bottom of the electrical cabinet, opposite each ventilation block, to allow the air flow to circulate throughout the internal volume V1 of the electrical cabinet (see figures 12A And 12B ).

[0020] In reference to the figures 1 And 2, a ventilation unit 5 according to the invention comprises a housing 6 mainly comprising a base 60 and a cover 61 assembled on said base and a fan VENT housed in said housing 6.

[0021] The ventilation block 5 has the shape of a straight block with a square base, which, as will be seen below, allows it to be easily combined with other identical ventilation blocks, in a limited space requirement. The ventilation block 5 thus has an upper face, a lower face and four parallel side faces in pairs.

[0022] Its base 60 comprises a lower wall 600 whose external face forms the lower face of the block 5 and several lateral sides, produced along the four lateral faces of the ventilation block.

[0023] The lower wall of the base 60 has an opening 62, for example of circular shape, and around this opening, a seat 63 for assembling the fan VENT of the ventilation unit 5. Means for fixing the fan may be provided on said seat 63 to ensure the fixing of the fan in its housing. The fan VENT is positioned on the seat 63 to make its air inlet coincide with the opening 62. A grille 620 of circular shape may be placed in front of its opening 62.

[0024] The side wall of the base 60 is produced in the form of four grilles, called internal grilles 601, produced along the four faces of the ventilation block 5.

[0025] The cover 61 is intended to be assembled on the base 60 to close it from above. It is in the form of a plate whose external face forms the upper face of the ventilation unit.

[0026] The block 5 also comprises four movable grids, called external grids 501, each intended to be placed in front of an internal grid 601 of the base to be able to position themselves along a distinct lateral face of the block. Each of these movable external grids 501 is pivotally mounted around an axis which follows the upper edge of the lateral face of the block 5. Each movable external grid 501 can be fixed to the cover and can comprise two opposite fixing lugs 502 each pivotally mounted in an orifice of the cover 61. Each movable external grid 501 can thus take a so-called closed position in which it is folded against the corresponding internal grid 601 of the base and one or more other open positions in each of which it can be pivoted around its axis according to a particular, non-zero angle of inclination.

[0027] The inner grids 601 and the outer grids 501 each have fins. The fins of each inner grid 601 are inclined at an acute angle relative to a vertical plane and the fins of each corresponding outer grid 501 are inclined symmetrically relative to said vertical plane (then forming chevrons) (see figure 6B ).

[0028] Along each of its external edges, the cover 61 may also comprise a separate slot 64 which opens into an internal housing of the casing 6. This housing is located just in front of the corresponding internal grid 601 of the base and is arranged to accommodate a filtration element 65. For each slot 64, the cover may comprise a pivoting flap 640 intended to cover the slot in the closed position and to allow access to the slot 64 and to the housing in the open position after pivoting.

[0029] The filtration element 65 may be any foam-type element or equivalent capable of retaining particles and allowing an air flow to pass through.

[0030] The ventilation unit 5 may also include a plate 66 arranged between the fan head and the cover, intended to hold the fan in the ventilation unit.

[0031] Furthermore, the ventilation unit 5 may also include a protective cover 67 ( figure 5 ), added to strengthen its protection index (IP). This protective cover 67 takes the form of a hat and comprises a square-shaped upper plate intended to rest on the cover and several inclined sides 670 downwards and outwards, each intended to be positioned in front of a separate side face of the block to protect it.

[0032] According to a particular feature, the ventilation block 5 according to the invention thus has an architecture which allows it to offer different protection indices, simply by changing its configuration. figures 6A à 6E thus illustrate the different configurations of the ventilation unit, for each protection index.

[0033] Figure 6A - IP41: To be in this first configuration, the block does not integrate the filtration elements and each external grid 501 is pivoted by a determined non-zero angle and advantageously less than 90°.

[0034] Figure 6B - IP44: This second configuration is identical to the first configuration, except that the external grids 501 are all folded and are therefore positioned in front of each internal grid 601.

[0035] Figure 6D - IP54: This third configuration takes up the characteristics of the first configuration, by adding a filtration element 65 in front of each internal grid 601. In this configuration, the external grids 501 are therefore each pivoted by a determined non-zero angle.

[0036] Figure 6C - IP55: This fourth configuration is identical to the third configuration, except that the external grids 501 are folded against the internal grids 601.

[0037] Figure 6E - IP55 "exterior": This fifth configuration is identical to the fourth configuration, the ventilation unit also including its protective cover 67 covering its casing.

[0038] Furthermore, it should be noted that each of these five configurations also allows the air flow to be adjusted. The flow rate may indeed be maximum in the first configuration. It will be lower in the second configuration, as it is slowed down by the external grilles 501, and even lower in the third configuration due to the addition of the filtration elements.

[0039] As mentioned above, the square shape of the ventilation block 5 allows it to be easily associated with one or more other identical ventilation blocks, optimizing the space occupied.

[0040] According to a feature of the invention, it is in fact possible to juxtapose at least two ventilation blocks in accordance with the invention on the upper wall of the cabinet. The two blocks 5.1, 5.2 are joined together, so that a lateral face of one bears against a lateral face of the other.

[0041] There figure 7 first illustrates a solution with a single ventilation unit 5.1. This can, for example, be placed centrally on the upper wall of the electrical cabinet.

[0042] There figure 8 then illustrates a solution with two ventilation blocks 5.1, 5.2 juxtaposed, placed on the upper wall 11 of the electrical cabinet 1. In this solution, as visible on the figure 10 , to achieve a close juxtaposition, the external grilles 501.1, 501.2 leaning against each other are necessarily folded against their respective internal grille 601.1, 601.2. It can be noted that the external grilles of the non-close faces could for their part be raised according to the chosen IP configuration. In this configuration, the perfect fit of the two ventilation blocks 5.1, 5.2 makes it possible to avoid any backflow of air in this zone and therefore any loss of efficiency of the two-block system. On the figure 10 , the filter elements 65.1, 65.2 are present but remain optional.

[0043] There figure 9 represents a solution with four ventilation blocks 5.1, 5.2, 5.3, 5.4 juxtaposed, placed on the upper wall of the electrical cabinet. The four blocks thus form a large square. In this solution, each ventilation block thus has two of its side faces which are joined with a side face of an adjacent ventilation block. As previously, the junctions are made in such a way as to avoid any air backflow and therefore do not cause any loss of efficiency. The external grilles of the non-joining faces can be raised to meet a particular protection index.

[0044] In the case of outdoor installation ("outdoor" version), it is also possible to provide a cover of a suitable shape, covering two, three or four juxtaposed ventilation blocks.

[0045] The possibility of arranging several ventilation units 5.1, 5.2, 5.3, 5.4 in accordance with the invention on the same upper wall 11 of an electrical cabinet 1 makes it possible to easily adjust the air flow rate necessary for cooling the electrical devices 13 present in the electrical cabinet 1. It is in particular possible to increase or decrease the number of ventilation units installed on the cabinet according to the need.

[0046] According to a particular aspect of the invention, illustrated by the figure 11 , it is also possible to provide two ventilation blocks 5.1, 5.2 in accordance with the invention, used in redundancy thanks to the addition of a suitable air flow management system 2 in the overall electrical installation. This air flow management system 2 may comprise a housing 22 in the form of two ducts 20, 21 connected to each other at right angles and advantageously placed inside the volume of the electrical cabinet 1. The first duct 20 may comprise several air inlets IN1, IN2 through which the air flow generated in the electrical cabinet enters. The second duct 21 extends along an axis (X) and comprises for its part two openings 210, 211 each forming a separate air outlet OUT1, OUT2 placed in communication with a separate ventilation block. This system further comprises an air flow control device 3 composed, for example, of two pivoting movable flaps 30, 31.The two movable flaps 30, 31 are able to take a first position, called closed, in which they close the connection between each air inlet IN1, IN2 and the second air outlet OUT2 and a second position called open, in which they allow the connection between each air inlet IN1, IN2 and the second air outlet OUT2. Advantageously, the two movable flaps 30, 31 can be controlled and able to pivot by the sole pressure of the air flow circulating in the second chute of the system.

[0047] It can also be noted that the system is located in volume V1 of the electrical cabinet while the two ventilation blocks 5.1, 5.2 are outside the electrical cabinet.

[0048] In reference to the figures 12A And 12B , the principle of redundant operation of the two ventilation blocks 5.1, 5.2 is as follows: In a first operating state of this system ( figure 12A ), the fan VENT1 of the first ventilation unit 5.1 is in operation and the fan VENT2 of the second ventilation unit 5.2 is stopped. The air flow F1 taken from inside the electrical cabinet 1, enters the system through each air inlet IN1, IN2, passes into the first chute 20 to reach the second chute 21. The fan VENT1 being in operation, the air flow F1 is driven towards the first air outlet OUT1 of the system 2 and escapes to the outside via the first air outlet OUT1 and the fan VENT1. The fan VENT2 being stopped, no air flow pushes the movable flaps 30, 31, these then remaining in their closed position. In a second operating state of this system ( figure 12B), the fan VENT1 of the first ventilation unit 5.1 is stopped (for example, it is broken down or undergoing maintenance...). The fan VENT2 of the second ventilation unit 5.2 is activated. The air flow F2 taken from the volume V1 of the electrical cabinet 1, enters the system 2 through each air inlet IN1, IN2, passes through the first chute 20 to reach the second chute 21. With the fan VENT1 stopped and the fan VENT2 operating, the air flow F2 heads towards the second air outlet OUT2. The air flow F2 applies pressure to the movable flaps 30, 31 and pushes them to pivot. The air flow F2 thus passes through the opening created by the pivoting of the flaps and reaches the second air outlet OUT2 to be evacuated to the outside thanks to the fan VENT2.

[0049] It can be noted that the detection of the stopping of the VENT1 fan and the activation of the VENT2 fan can be carried out by any means, automatic and / or manual.

[0050] The solution of the invention thus presents numerous advantages, among which: A reliable 5 ventilation unit solution that allows us to offer, from the same architecture, several different protection indices; A 5 ventilation unit that is easy to install and to combine with one or more other identical ventilation units, allowing us to offer great modularity and a solution that can be adapted to your needs; A 5 ventilation unit with a simple architecture, while being particularly effective.

Claims

1. A ventilation unit (5) for an electrical enclosure, comprising a fan (VENT) and a housing (6) which comprises a base (60) and a cover (61) assembled on the base, in which the housing (6) has the shape of a right block with a square base, four side faces and a top face, in which said base (60) comprises a bottom wall (600) forming said base of the housing and a side wall following the four side faces of the housing, an opening (62) made through its bottom wall and a seat made around its opening and housing the fan, in which the cover (61) is affixed to the base (60) and comprises the upper face of the housing, and in which, along each side face, the side wall of the base comprises a first grid (601), characterised in that, along each lateral face, the ventilation unit (5) comprises a second grid (501) mounted so as to pivot between: - a closed position, in which the second grid (501) covers the first grid (601) of the corresponding lateral face, being folded against this first grid, so that the ventilation unit (5) has a first configuration defining a first protection index (IP) of the ventilation unit, and - one or more open positions, in each of which the second grid (501) is raised with respect to the first grid (601) of the corresponding side face, being pivoted at a determined angle of inclination which is non-zero, so that the ventilation unit (5) has a configuration which is different from the first configuration and which defines a protection index (IP) of the ventilation unit, different from the first protection index.

2. A ventilation unit according to claim 1, characterised in that it comprises a plurality of internal housings of the housing (6), which are each arranged in front of each first grid of the base, and in that the ventilation unit comprises a separate filtration element (65) positioned in each housing, in front of each first grid of the base.

3. A ventilation unit according to claim 2, characterised in that the cover comprises a plurality of pivoting flaps (640), each giving access to a separate housing accommodating the filter element (65).

4. A ventilation unit according to one of claims 1 to 3, characterised in that each second grid (501) is fixed to the cover (61) and mounted so as to pivot on said cover.

5. A ventilation unit according to one of claims 1 to 4, characterised in that it comprises a protective cover (67) forming a cap intended to cover said housing (6).

6. A ventilation unit according to claim 5, characterised in that the protective cover (67) comprises a main wall affixed to the cover and a plurality of inclined lateral flanks extending in front of the lateral faces of the said housing (6).

7. A ventilation unit according to one of claims 1 to 6, characterised in that, in the or each open position, the angle of inclination is less than 90°.

8. An electrical installation comprising an electrical enclosure having a bottom wall (10), a top wall (11), and side walls (12), the installation being characterised in that it includes a modular ventilation system comprising a plurality of identical independent ventilation blocks (5.1, 5.2, 5.3, 5.4), each ventilation unit being as defined in one of claims 1 to 7 and positioned on the top wall (11) of the electrical enclosure.

9. An electrical installation according to claim 8, characterised in that the ventilation units are positioned on the top wall (11) of the electrical cabinet so as to be joined by at least one of their lateral faces at which the respective second grilles (501) of the ventilation units are each in their closed position.

10. An electrical installation according to claim 8 or 9, characterised in that it comprises an air flow management system which can be fitted to the electrical enclosure, the said air flow management system comprising: - A housing (22) comprising at least one air inlet (IN1, IN2) intended to be placed in communication with the internal volume (V1) of the electrical enclosure, at least two air outlets (OUT1, OUT2) and at least one main duct (20) arranged to connect said air inlet (IN) to the two air outlets (OUT1, OUT2), - A diverter device (3) arranged inside said main duct (21), between the first air outlet (OUT1) and the second air outlet (OUT2), said diverter device comprising movable flaps (30, 31) controllable between a first position in which the air inlet communicates only with the first air outlet and a second position in which the air inlet communicates at least with the second air outlet.