FR2679020A1 - Transportable and dismantleable refrigerating device for market (fair) stall displays - Google Patents

Abstract

Transportable and dismantleable refrigerating device for market stall displays, including at least one table (3) for displaying perishable foodstuffs and a refrigeration unit (11) equipped with a pump (53) for circulating a refrigerant fluid (56) intended to flow through a cold (heat) exchanger consisting of the display table itself (3) and including a planar metal plate intended directly to support the foodstuffs and a corrugated plate fixed to the lower face of the planar plate, so as to define a plurality of flow channels for the refrigerant fluid. The device is characterised in that the channels are connected to an input header (water) box and to an output water box for the refrigerant fluid, and in that the pump (53) for circulating this fluid (56) works in suction. Application to the refrigeration industry.

Description

TRANSPORTABLE AND REMOVABLE REFRIGERATOR DEVICE FOR
FOREIGN MARKET SHOWERS
The present invention relates to a transportable and dismountable refrigerating device for displays in fairground markets and, in general, for displays located outside, especially in front of shops.

 Such a device aims to solve the long felt need for a satisfactory solution for the conservation and maintenance of hygiene of perishable foodstuffs in fairground markets, so as to eliminate the risk of their degradation during the period of exposure to heat and / or air in these markets, that is, outside.

The solution described in the patent application
FR-2 633 375, comprising at least one display table for perishable foodstuffs and a refrigeration unit, uses as a heat exchanger a coil fixed to the underside of a metal plate for supporting the foodstuffs of which the table is composed display.

 However, this solution has the drawback of poor refrigeration of the food support plate, due to the fact that the contact between the sheet and the coil is made only along the generator of the coil which is applied against the face bottom of the refrigeration plate, which results in the existence of a double thermal gradient between the refrigeration fluid conveyed inside the coil and the coil itself as well as between the latter and the refrigeration plate. The consequence of this arrangement is that the distribution of frigories on the cooling plate is not uniform, with concentration of the frigories generated along the path of the coil only, so practice has shown that it is impossible to uniformly cool the whole from the surface of the refrigeration plate of a food display table from a coil. In addition, the adoption of a coil leads to significant pressure losses for the circulation of the refrigerating fluid, these losses increasing all the more that the pitch of the coil is small (that is to say that the distance between two adjacent pipes of the coil is small), due to the existence of bends of small radii causing turbulence in the movement of the coolant.In addition, the cost of a coil is relatively high because of the large length of the tube which is necessary to use, a disadvantage to which is also added that of the difficulty of centering the coil, in particular in the case of curvatures of small radii, which is the case in this kind of application for concentrating the maximum in a small space of frigories.

 Fully metallic exchangers are also known which are obtained by inflating two superposed sheets and connected by a matrix of weld points and sealed at the periphery by continuous welding, the inflation of these two sheets thus connected together giving rise to the formation of mattresses. metal with a plurality of metal cushions separated by depressions corresponding to the welding points. However, also this type of exchanger does not lend itself to the refrigeration of a food support plate because contact with the plate would be limited to the small application areas of the metal cushions of the mattress against the underside of the plate, which amounts to saying that this second solution would have the drawback already mentioned in connection with the use of a coil; in addition, this second solution faces weight problems, because the exchanger is completely metallic, and price.

The drawback of non-uniform contact between the cold exchanger and the food support plate has been resolved by adopting a cold exchanger delimited by a flat metal plate for supporting the food itself and by a plate corrugated metal which is welded to the flat plate by welding points so as to define channels for circulation of the refrigerating fluid, which is thus in direct contact with the food support plate: see in this regard the Patent
US-2 973 631. However, also this solution
has drawbacks, because it still adopts the circulation of the cooling fluid in a coil, which does not allow uniform cooling of the plate and which results in significant pressure losses and, secondly, because the injection of the refrigeration in this exchanger by the refrigeration unit pump associated with the display table causes the weld points to burst, thus rendering the structure unusable. In addition, the spot welding of the corrugated plate to the flat plate destroys the stainless character of the latter, which is intended to come into direct contact with foodstuffs, which is unacceptable in this type of application because of the rust appears along the weld lines.

The present invention has therefore set itself the aim of providing a refrigerating device for market displays which meets the necessities of practice better than devices of the same type and aiming at the same object previously known, in particular in that
- it makes it possible to eliminate the drawbacks linked to the exposure of perishable foodstuffs in fairground markets and therefore to comply with hygiene and conservation standards to safeguard the health of consumers;
- it is easily transportable and therefore suitable for the needs of the fairground markets;
- it lends itself to be quickly assembled and disassembled, without tools and in just a few minutes, which is another advantageous aspect due to the destination of this type of product;
- it is modular and therefore easily adaptable to the different qualities and quantities of goods to be displayed for sale;
- the hydraulic handling of the exchanger is reduced to a minimum and it does not require the execution of a purge, because there is no risk of air pockets forming;
- The refrigeration of the food support plate is perfectly uniform over the entire surface of the plate;
- this support plate retains its stainless character compatible with food use.

 The present invention relates to a transportable and dismountable refrigerating device for displays in fairground markets, comprising at least one display table for perishable foodstuffs and a refrigeration unit equipped with a pump for circulating a refrigeration fluid intended to circulate. in a cold exchanger which is constituted by the spreading table itself and which comprises a flat metal plate intended to directly support the foodstuffs and a corrugated plate fixed to the underside of the flat plate, so as to define a plurality of refrigerant circulation channels, characterized in that the channels are connected on one side to an inlet water box and on the other side to a refrigerant outlet water box, these two water boxes being open on the side of the metal plate and being made in one piece with the channels formed in the corrugated plate, which is made of plastic, and in that the circulation pump for this fluid works by suction, that is to say by creating a vacuum in the exchanger, which is thus filled with refrigeration fluid by depression.

Other characteristics and advantages of the invention will appear in the description which follows, given by way of example and with reference to the appended drawings, in which the same references refer to the same elements or to elements of the same type and
- Figure 1 is a perspective view of a first embodiment of the device according to the invention;
- Figure 2 is a perspective view, with parts broken away, of the cooling panel according to the invention;
- Figure 3 is a perspective view of the corrugated plate of the panel illustrated in Figure 2, Figure 3A being a section along A of this corrugated plate;
- Figure 4 is a top view of the panel illustrated in Figure 2, Figure 4A-B being a section along A or B of Figure 4, while Figure 4C is a section along C ;;
- Figure 5 is a sectional view illustrating the fitting of push-pull type fittings, used in the device according to the invention;
- Figure 6 is a block diagram illustrating the circulation of the refrigerating fluid in the cooling panels;
- Figures 7 to 10 illustrating in perspective the support posts of the food protection display cases, the post of Figure 7 being intended to be used between two adjoining panels on the client side, whereas that of Figure 9 is intended to be used between two adjoining panels on the merchant side. The post of FIG. 8 and of FIG. 10 being corner posts intended to be used respectively on the client side and on the merchant side;
- Figure 11 illustrates the refrigeration unit on wheels associated with the cooling panels;
- Figure 12 is a perspective view of a second embodiment of the device according to the invention.

 The refrigeration device 100 for stalls of fairground markets illustrated in FIG. 1 is of the type intended to be supported by trestles 9. It comprises, by way of example, four refrigeration tables 3 juxtaposed horizontally, so as to cover a surface 3.9 mx 0.9 m, each table measuring 0.975 mx 0.9 m. A refrigeration unit 11 makes it possible to circulate through the various tables arranged in cascade the refrigerating fluid, in particular consisting of glycol water. To this end, it comprises a suction pipe 10, the function of which will be described in detail below, and a pipe 13 for entering the refrigerating fluid, the passage of the fluid from one table to the next table taking place using a hose 12.

 The refrigeration exchanger frigory table according to the invention, which is illustrated in FIG. 2, comprises a flat metal plate 20 preferably made of stainless steel, which is intended to come into direct contact with the foodstuffs exhibited for sale. , as well as a corrugated plate 21 made of plastic, in particular of composite material and in particular of polyester reinforced with glass fibers. This plate is glued to the underside of the flat plate 20 along the upper regions 28 of the corrugated plate 21, the profile of which is illustrated on a larger scale in FIG. 3A. In this way, parallel circulation channels 30 are defined. direct refrigeration fluid, which is introduced into a table by an inlet water box 31 and which exits towards the successive table by an outlet water box 32, these two water boxes 31 and 32 and the channels 30 being made in one piece. It is easy to understand that the use of this corrugated plate 21, in which the two abovementioned water boxes 31 and 32 are arranged, open like the channels 30 on the side of the flat metal plate 20, constitutes a solution which is very effective for the cooling of the metal plate 20, because the circulation of the fluid does not take place in a serpentine, but simultaneously along parallel paths between them, defined by the channels. The result is that the metal plate 20 for supporting foodstuffs is uniformly refrigerated over its entire surface with optimum performance. In addition, the plastic plate 21 constitutes a good means of thermal insulation, which further increases the efficiency of the device. In addition, the various corrugations of the plate 21 form support beams for the metal plate 20 and the foodstuffs that it is intended to receive, this support function being able to be improved by providing the lower zones 29 of the corrugated plate 21 with reinforcement ribs (not shown), which also come in one piece with the plastic plate 21.

 Also the thermal insulation of each refrigeration table can be improved using an additional insulator constituted for example by polyurethane 22 contained in an insulation tank 25 (cf. FIG. 2). Advantageously, this plastic container 25 can be equipped with grooves 27 intended to receive rails (not shown) for centering the refrigeration tables, these rails being fixed to the trestles.

 It should also be noted that the use of the corrugated plate 21 of plastic material avoids spot welding for fixing to the metal plate 20 and makes it possible to respect the stainless character of the latter.

 The metal plate 20 advantageously comprises a gutter 24 for evacuating the condensates produced by stamping (see also FIG. 4) the evacuation taking place through the orifice 23 in a symmetrical position. On this metal plate 20 are also provided, at the four corners, orifices 26 allowing the installation of protective display elements illustrated in FIG. 1. To this end, a solution is adopted within the framework of the present invention allowing quick and tool-free assembly and disassembly of these display elements. This is achieved through the use of corner posts 1 and 8 intended to be placed on the customer side and the merchant side, respectively, as well as intermediate posts 4 and 5 also intended to be placed on the customer side and merchant side, respectively. These posts are illustrated in detail in Figures 7 to 10.

 The inlet and outlet ports 33 and 34 of the fluid are formed in the corresponding water boxes 31 and 32 on the same side of the plate 20 (see FIGS. 1 and 3), although they can be arranged therein according to a diagonal.

 As regards the corner posts 1 (see FIGS. 1 and 8), they comprise an anchoring pin 36 intended to be introduced into one of the aforesaid corresponding holes 26 of the metal plate 20, into which we have previously introduced an anchoring tube 37 (see FIG. 4A). Of course, the plate 20 is stamped in the locations of the anchoring tubes 37 of the pins of the support posts of the display cabinet elements to preserve the touching character of the whole of the plate 20 (cf. FIG. 4A). An evacuation tube, preferably identical to the anchoring tube 37, is also inserted into the evacuation orifice 23 formed in the gutter 24 mentioned above (cf. FIG. 4C). Each post 1, which is inclined side merchant, also includes grooves 38 for sliding the elements of the side window 2 and client side 14 (see FIG. 1), which can be made of glass or transparent plastic for food use. Regarding the corner post 8 on the merchant side (see Figures 1 and 10), this differs from the corner post 1 on the customer side in that it is vertical instead of being inclined and in that 'it has a reduced height, but it also has sliding grooves 37 of the elements of the lateral display case 2 and on the merchant side 7. The corner posts 1 and 8 advantageously comprise three sliding grooves of the corresponding display elements instead of two grooves to make them interchangeable and facilitate assembly without having to distinguish between location on the right and on the left for corner posts of the same type. As for the intermediate posts 4 on the client side (Cf Figures 1 and 7), also are inclined like the corner posts 1 on the client side and differ from them by the presence, at the base, of a horizontal plate (40) equipped with two anchoring pins 36a and 36b so as to maintain juxtaposed two tables of contiguous refrigeration 3 by location of the pins 36a and 36b in the orifices 26 of the plate 20 crossed by the corresponding anchoring tubes 37 of two juxtaposed tables, while supporting the elements of display case 14.

 In addition, the posts 4 also have a support beam 39 for the horizontal display elements 6 on the customer side, the presence of which complies with the legislation in force. With regard to the intermediate posts 5 on the merchant side (see FIGS. 1 and 9), these differ from the intermediate posts 4 on the customer side only in their reduced height and their vertical orientation.

 The circulation of the refrigeration fluid is carried out using the refrigeration unit 11 (Cf Figures 1 and 11) comprising a frame 41 and a cover 42 comprising ventilation windows whose function will be described below. In FIG. 11, there is shown schematically the compressor 44 of the primary refrigeration fluid, normally constituted by freon, as well as a tank 45 enclosing a coaxial evaporator 51, known to technicians in the field, embedded in an appropriate thermal insulator 46 and containing in the center a reservoir 47 for refrigerating the secondary refrigerating fluid 56, in particular constituted by glycol water, as already mentioned above.

 This secondary refrigeration fluid passes through the circulation jacket 57 of the coaxial evaporator 51 (see also FIG. 6) inside which is the tube 58 for the passage of the primary refrigeration fluid, that is to say freon. A tube 59 allows the passage of the secondary refrigeration fluid 56 from the circulation jacket 57 to the reservoir 47. This reservoir 47 is connected, by means of a starting tube 49 (cf. FIG. 11) equipped with a connector. rapid push-pull type 50 to the pipe 13 for entering the refrigerant in the spreading tables 3 while the jacket 57 for circulation of this fluid in the coaxial evaporator is connected to the suction pipe 10, on which A self-aspirating pump 53 is mounted. In fact, contrary to current practice in this type of device, the circulation pump works - within the framework of the present invention - in suction, that is to say that it creates the vacuum in the frigory exchanger, constituted by the refrigeration tables 3 connected in cascade, instead of injecting the refrigeration fluid under pressure: this has the consequence that the exchanger is filled with refrigeration fluid using the pipe 13 following the dep recession created there by the pump using the aforementioned suction pipe 10. In this way, atmospheric pressure is used to keep the corrugated plate 21 made of plastic glued to the flat metal plate 20 of each refrigeration table. , because the suction makes it possible to request the fastenings by bonding between the two plates in compression and not in traction, which would be the case if the refrigeration fluid were injected under pressure into the tables forming the exchanger. prevents deformation and bursting of the exchanger, which takes place in the prior art because of the adoption of pressure injection of the refrigerant and which makes this type of refrigeration device practically impracticable despite the abundant literature which has existed for a very long time, in which the technical problem which the present invention aims to solve and which is posed by the injecti pressurized refrigeration fluid.

 Given the destination outside the device according to the invention, the refrigeration unit 11, which is of the type on wheels 54 to make the assembly easily transportable, comprises in its cover, in addition to the side ventilation windows 55 , also, ventilation windows 60 directing the hot air produced by the radiator 43 for refrigerating the freon compressor 44, under the action of a fan 61 towards the feet of the merchant, in particular when the outside temperature is relatively low, In addition, in the case where the outside temperature is very low, it is also advantageous to envisage the use of a heating resistor 48 inserted in the reservoir 47 of the refrigerating fluid 56 to ensure a temperature at each level. refrigeration table 3 which is compatible with the good preservation of foodstuffs, so that they are not damaged by excessive cold sif: in this regard, maintaining a temperature around 0 C, and sometimes +4 "C, seems best suited for this kind of application. It should also be noted that the suction operation of the pump 53 of the refrigeration unit 11 avoids the presence of air pockets in the refrigerant exchanger 3, which is advantageous for uniform cooling of the food support plate 20, while avoiding the need to perform purges .

 It is important, moreover, to draw attention to the fact that the quick couplings 50 of the push-bull type and with double obturation with which each refrigeration table is also fitted, are arranged so as not to protrude from the vertical space requirement of each table (see FIG. 5), which makes it possible to superimpose the refrigeration tables on one another without the risk of actuation of the drain valve 62 with which these fittings 50 are fitted. The reference 63 in Figure 5 shows an insert allowing the connection of a connector 50 to the corrugated plate 21 (Figure 5 actually corresponds to a section along B or C of Figure 3).

 A preferred embodiment of the refrigeration device according to the invention is the device 200 which is shown in perspective in Figure 12 and which uses a small trailer 70, inside which are housed, during transport, the refrigeration unit and display elements, while the refrigeration tables are stored above the trailer.

This solution eliminates the use of support trestles and makes the use of the device very convenient.

As a means of supporting the refrigeration tables, sliding rails (not shown) can be used inside the trailer during transport: these are for example rails having a C-shaped section inside which is housed a pivoting leg 16 intended to bear on the ground for the support of the juxtaposed plates.

 A refrigerating device has thus been produced for showcases in fairground markets which satisfies the aim of the invention thanks to the design of the frigory exchanger serving as a display table for foodstuffs and to the adoption of a pump working in suction. as well as the use of elements whose assembly and disassembly is rapid and is carried out without tools, the assembly time not exceeding a quarter of an hour for a single person.

Claims (10)

 1 - Transportable and dismountable refrigerating device for displays in fairground markets, comprising at least one table (3) for displaying perishable foodstuffs and a refrigeration unit (il) equipped with a circulation pump (53) of a refrigeration (56) intended to circulate in a frigory exchanger, which is constituted by the display table itself (3) and which comprises a flat metal plate (20) intended to directly support the foodstuffs and a corrugated plate ( 21) fixed to the underside of the flat plate, so as to define a plurality of channels (30) for circulation of the refrigerating fluid (56), said device being characterized in that the channels (30) are connected side to an inlet water box (31) and on the other side to an outlet water box (32) for the refrigerant (5 G), these two water boxes (31,32) being open from side of the metal plate (20) and both made in one piece with the channels (30) formed in the corrugated plate, which is made of plastic, and in that the pump (53) for circulation of this fluid (56) works in suction, this is that is, by creating a vacuum in the exchanger (3), which is thus filled with refrigeration fluid (56) by vacuum cooling.  2 - Device according to claim 1, characterized in that it comprises a plurality of display elements (2,6,7,14) which are held in place by corner posts (1,8) and intermediate ( 4,5) fitted with grooves (38) for sliding the elements of the display case and anchor pins (36) intended to be inserted into holes (26) formed around the periphery and at the corners of the display table (3 ).  3 - Device according to claim 2, characterized in that the customer side corner posts (1), as well as the merchant side corner posts (8), have three grooves (38) for sliding the display elements (2 , 14; 2,7) so as to be interchangeable, in that the customer-side intermediate posts (4), as well as the merchant-side intermediate posts (5), have two anchoring pins (36a, 36b) projecting from 'a plate (40) and intended to be inserted into the orifices (26) of two contiguous spreading tables (3) so as to keep them juxtaposed while supporting the elements of the display case (14; 7), and in that the customer-side intermediate posts (4) also include a beam (39) for supporting horizontal display elements (6).  4 - Device according to any one of claims 1 to 3, characterized in that the plate (20) for supporting foodstuffs comprises a gutter (24) for evacuating condensates.  5 - Device according to any one of claims 1 to 4, characterized in that the spreading table (3) making the heat exchanger comprises a tank (25) of thermal insulation filled with a bed of insulating material (22 ) and arranged below the corrugated plate (21) made of plastic.  6 - Device according to claim 5, characterized in that the thermal insulation tank (25) has a groove (27) for centering this tank and therefore the corresponding spreading table (3) on support rails .  7 - Device according to claim 6, characterized in that the support rails are intended to be fixed to trestles (9) for supporting the display tables (3).  8 - Device according to claim 6, characterized in that the support rails are slidably incorporated in a trailer (70) for loading and supporting the display tables (3) as well as the refrigeration unit (11), showcase elements (2,6,7,14) with their support posts (1,4,5,8) and connection pipes (10,12,13), these sliding rails in turn incorporating pivoting feet ( 16)  9- Device according to claim 1, characterized in that the pipes (10,13) connecting the suction pump (53) to the extreme spreading tables and the pipes (12) connecting two spreading tables juxtaposed to allow the circulation of the refrigeration fluid (56) are equipped at their ends, like the spreading tables themselves, with quick couplings with double shuttering of the push-pull type (50).  10 - Device according to claim 9, characterized in that the quick couplings (50) with which the display tables are fitted are arranged so as not to exceed the vertical size of each table and thus allow the superposition of the tables of the device without risk of unwanted emptying, especially during transport and / or assembly and disassembly operations.