EP3290835B1

EP3290835B1 - Refrigerated display case and corresponding refrigeration method

Info

Publication number: EP3290835B1
Application number: EP17188153.5A
Authority: EP
Inventors: Stefano CARLONI; Giovanni Piersigilli
Original assignee: Industria Frigoriferi Italiana SpA
Current assignee: Industria Frigoriferi Italiana SpA
Priority date: 2016-08-30
Filing date: 2017-08-28
Publication date: 2019-09-25
Anticipated expiration: 2037-08-28
Also published as: EP3290835A1; IT201600088205A1; PL3290835T3

Description

FIELD OF THE INVENTION

The present invention concerns a refrigerated display case for displaying and preserving food products, such as ice cream and suchlike. The present invention can also be applied to other goods that generally require display and preservation at a controlled temperature.

BACKGROUND OF THE INVENTION

It is known that the humidity in the air tends to deposit on the surface of the body which has a lower temperature than that of the air. The deposition of humidity on food products forms a layer of condensation that, at the temperatures considered, can cause the formation of frost or ice. This formation can lead to a loss of the organoleptic properties and/or a reduction in the aesthetic value, or a deterioration in the food products.
Food products, at least those that require low temperature storage, that is, lower than 0°C, and exposure to air, are generally displayed and stored in a refrigerated display case, which prevents the formation of frost on them.
In document JP H08136107 A , for example, a known cold air circulation type showcase according to the preamble of claim 1 is described.
A known refrigeration cabinet for individually sold food products is also described in document FR 2688299 A1 .
The refrigerated display case comprises at least two compartments: a first compartment, or display compartment, where the food products are put and displayed, and a second compartment, or technical compartment, generally disposed below the first compartment.
The display compartment generally consists of a support plane on which the food products are positioned, and a display cabinet made of a transparent material to allow the food to be visible inside the showcase.
The display cabinet can in turn be provided with a door, usually sliding, to allow access to and removal of food products from the display compartment.
The technical compartment is provided with a refrigeration plant, which generates and circulates a flow of refrigerated air in the refrigerated display case.
The flow of air keeps the food products at the desired temperature.
The refrigeration plant is provided with at least an evaporator that cools the air. The refrigerated display case also comprises a fan, usually installed in the technical compartment and configured to generate a flow of air through the evaporator and along an air passage circuit comprised between the evaporator, over the food products, and again through the evaporator.
Due to its low temperature, the evaporator captures the air humidity that is deposited on it, forming condensation.
The condensation transforms into frost or ice, which reduces the functioning efficiency of the evaporator with negative consequences both for the preservation of the food products and also for the performance of the refrigeration plant.
Therefore, a defrosting step of the evaporator is required, using a defrosting device which heats the evaporator periodically and for a few minutes, taking it to temperatures of about 10°-15°C and thus removing the frost or ice.
It is known that the air that circulates in the refrigeration plant has a very low temperature, which can also reach about -20°C and which impedes the heating of the evaporator and the removal of frost or ice.
The state of the art provides to interrupt the flow of air in the circuit by blocking the fan for short and regular periods of time, thus facilitating the heating of the evaporator. Furthermore, stopping the fan allows to not introduce into the air circuit the humidity generated by the melting of the frost or ice present on the evaporator.
When the flow of air is interrupted, the air in the display compartment can be heated by the air of the external environment, taking on humidity. The air humidity in the display compartment can then be deposited on the food products, causing the disadvantages described above.
One known solution provides to install at least two evaporators in the technical compartment, which are made to function alternately, that is, while one is functioning, the other is switched off to allow it to be heated and therefore allow the ice that has formed to be defrosted. This solution guarantees a continuous circulation of the flow of air over the food products, but it is very expensive because two evaporators are installed, and it is particularly complex to manage.
Another solution provides to divide the evaporator into two or more parts, so that when at least one of its parts is activated, the other one or more parts are subjected to defrosting.
One disadvantage of this solution is the complexity of the manufacturing and management of the refrigeration plant.
There is therefore a need to obtain a refrigerated display case which can overcome at least one of the disadvantages of the state of the art.
One purpose of the present invention is to obtain a refrigerated display case that is extremely effective in preserving food, preventing any deterioration thereof.
It is also a purpose of the present invention to obtain a refrigerated display case that is economical to make.
It is also a purpose of the present invention to obtain a refrigerated display case that has high functioning efficiency.
It is also a purpose of the present invention to obtain a refrigerated display case that is simple to manage.
It is also a purpose of the present invention to allow to modify refrigerated display cases already existing and installed in certain workplaces both simply, economically, and with few maintenance operations.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention.
In accordance with the above purposes, a refrigerated display case, according to the present invention, comprises a display compartment in which food products or other goods are displayed on trays or in tubs, and a technical compartment, separate from the display compartment and located in fluidic communication with the latter, for example by means of air feed channels, and in which at least one evaporator of a refrigeration plant is installed.
The evaporator is associated with a defrosting device configured to defrost the evaporator.
The technical compartment comprises at least a first pipe in which the evaporator is installed and defining with the display compartment a first circuit for the passage of the air.
According to the present invention, the technical compartment also comprises a second pipe in which a eutectic container made of deformable plastic is installed and defining with the display compartment a second circuit for the passage of the air.
The refrigerated display case also comprises at least one fan, installed in the technical compartment and configured to selectively generate a flow of air through the first circuit or through the second circuit for the passage of air.
In this way, when the evaporator is active, the fan generates a flow of air that passes through the evaporator and the display compartment, refrigerating the food products in the classic way.
When the defrosting of the evaporator is required, the fan generates a second flow of air that passes through the heat accumulator, which in the meantime has accumulated refrigeration thermal energy, to be cooled and sent to the display compartment.
During this step, the evaporator is switched off and defrosted using the defrosting device. The separation of the evaporator and the heat accumulator, achieved by the first pipe and the second pipe, prevents any possible humidity that forms during the defrosting of the evaporator from being circulated toward the display compartment, thus deteriorating any food products present therein.
The present invention also concerns a method to refrigerate food products contained in a display compartment that provides:

to activate an evaporator of a refrigeration plant to cool a flow of air circulating between the display compartment and a technical compartment, in which the evaporator is installed,
to defrost the evaporator using a defrosting device.

According to one aspect of the method according to the present invention, during the activation of the evaporator it is provided to generate a first flow of air through a first air passage circuit, defined between the display compartment and a first pipe of the technical compartment in which the evaporator is installed.
During the defrosting of the evaporator, on the contrary, it is provided to generate a second flow of air through a second air passage circuit, defined between the display compartment and a second pipe in which at least a eutectic container, made of a deformable plastic material, is installed and able to supply refrigeration energy. The first flow of air and the second flow of air are generated by at least one fan installed in the technical compartment.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

fig. 1 is a cross section of a refrigerated display case, object of the invention;
fig. 2 is a variant of fig. 1;
fig. 3 is a three-dimensional view of a container made of a deformable plastic material that can be used as a heat accumulator in both variants of the invention;
fig. 4 is a longitudinal section view of the heat accumulator in fig. 3.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

A refrigerated display case 10 according to the present invention comprises a display compartment 11 in which food products or other goods are displayed in containers 12, such as trays or tubs, and a technical compartment 13 disposed in a separate place from the display compartment 11, and in which at least part of a refrigeration plant 14 is installed.
The display compartment 11 can comprise a support structure 15 configured to support the containers 12.
According to possible solutions, the support structure 15 can itself define the separation between the display compartment 11 and the technical compartment 13.
The display compartment 11 can also comprise a panel 16 made of transparent material to allow the food products contained in the containers 12 to be visible.
The panel 16 can be suitably shaped, for example rounded, to confer a particular aesthetic appearance on the display compartment 11.
The display compartment 11 can also be provided with at least one aperture 17 to allow access to the food products contained in the display compartment 11.
A closing element, such as a door or other comparable or similar elements, can be associated, or associable on each occasion, with the aperture 17.
According to possible variant embodiments, air blade devices can be associated with the aperture 17 to prevent the air outside the display compartment 11 from entering through the aperture 17.
The display compartment 11 is put in fluidic communication with the technical compartment 13 so that the air generated in the technical compartment 13, as described below, can be circulated, in a closed loop, to the display compartment 11.
According to possible solutions, the technical compartment 13 and the display compartment 11 can be fluidically connected by means of a first connection channel 18 and a second connection channel 19.
Mouths 20 for the passage of the air can be associated with the first connection channel 18 and/or the second connection channel 19.
The refrigerated display case 10 also comprises a support base 21 configured to support the technical compartment 13 and the display compartment 11, as well as the components associated with them.
The support base 21 can define at least part of the technical compartment 13.
The technical compartment 13 can be defined by a plurality of walls 22 connected to each other to define a concave conformation, open upward during use, and in which at least part of the support structure 15 is positioned.
The walls 22, or at least some of them, can be made of heat insulating material to limit heat losses to the outside.
At least one evaporator 23 is installed in the technical compartment 13, configured to cool a flow of air that is made to pass through it.
The evaporator 23 can be part of the refrigeration plant 14.
In particular, it can be provided that the evaporator 23 is the type with refrigerating liquid air, that is, a finned battery in which the refrigerating liquid of the refrigeration plant 14 is made to circulate while the air is forced against the surfaces of the finned battery to be cooled.
According to one aspect of the present invention, the evaporator 23 is associated with a defrosting device 24 configured to defrost the ice that forms in the evaporator 23.
The defrosting device 24 can comprise at least one of either an electric resistance or a circuit to feed a heated fluid.
The defrosting device 24 can be installed inside the technical compartment 13 as shown in figs. 1 and 2, or outside it.
Devices, not shown in the drawings, to discharge the liquid deriving from the defrosting of the evaporator 23, can also be associated with the defrosting device 24 and/or the evaporator 23.
According to another aspect of the present invention, the technical compartment 13 is provided with a first pipe 25 for the passage of air, in which the evaporator 23 is installed.
The first pipe 25 is put in fluidic communication with the display compartment 11, in this way defining a first circuit 26 for the passage of air, schematized in figs. 1 and 2 by the lines of dots and dashes.
The first pipe 25 for the passage of air can be connected to the display compartment 11 by means of the first connection channel 18 and/or second connection channel 19.
According to the present invention, the technical compartment 13 is provided with a second pipe 27, separated from the first pipe 25 and in which at least one eutectic container 28 is installed, made of deformable plastic material and configured to accumulate cooling thermal energy, to be released when the evaporator 23 is deactivated.
The eutectic container 28, shown in one embodiment in figs. 3 and 4, comprises opposite walls formed by a first undulating profile 36 opposite to a second undulating profile 37.
The undulating profiles 36 and 37 advantageously allow to have a high heat exchange surface, on both sides of the eutectic container 28, between the air circulating in the refrigerated display case 10 and the eutectic container 28 itself.
Between the undulating profiles 36 and 37, a chamber 38 to contain a eutectic solution is substantially defined.
The undulating profiles 36 or 37 also allow the eutectic container 28 to rest stably on a corresponding support plane, for example a separation panel 30, even in the presence of deformations due to temperature variations in the eutectic solution.
This support will be guaranteed constantly and in multiple points by the various ridges 39 of the undulating profiles 36 or 37.
The deformable plastic material of which the eutectic container 28 is made also allows it to suitably adapt to the dilations due to the temperature variations of the eutectic solution.
Compared to a traditional heat accumulator, for example a metal block, the eutectic container 28 is therefore more effective and efficient.
In general, compared to traditional heat accumulators, the eutectic container 28 is certainly more economical.
Furthermore, as an alternative to what is shown here, the eutectic container 28 could be formed by a plurality of eutectic modules, for example similar in shape to the eutectic container shown. Such eutectic modules would allow to advantageously modify and vary the desired defrosting effect inside the refrigerated display case 10.
The eutectic container 28 is also advantageous because, compared to another type of traditional heat accumulator, it can easily be extracted, even by the final user, from the refrigerated display case 10. This possibility of extracting it therefore allows quick cleaning operations, possible replacement, or other.
The eutectic container 28 also has a considerable capacity for the eutectic solution, which is a kind of thermal flywheel. Thanks to this feature, it is possible to obtain an extension of the duration of the ON/OFF cycles of the compressor provided in the refrigeration plant 14.
If the duration of these compressor cycles is greater, the compressor will be started fewer times in the unit of time, for example, the number of times the compressor is started every hour will be reduced. Advantageously, by reducing the number of compressor start-ups in the unit of time, the life of the compressor is lengthened and consumption is reduced.
As we said, the undulating profiles 36 and 37 of the eutectic container 28 allow to have a high heat exchange surface compared with traditional heat accumulators and also provide the structural resistance needed to support and control heat dilations without being damaged.
In particular, as we said, the eutectic container 28 provided with undulating profiles 36 and 37 rests perfectly on the support plane by means of the ridges 39. A container with a rectangular section, for example, although in some ways equally advantageous with respect to traditional metal heat accumulators, could suffer uncontrollable deformations of the flat support wall. Such deformations could be the result, for example, of the solidification of the eutectic solution, so that the support wall would tend to bulge, for example in the center, therefore reducing its support surface and its supporting stability.
The second pipe 27 is also put in fluidic communication with the display compartment 11, for example by means of the first connection channel 18 and/or second connection channel 19, to define a second circuit 29 for the air to pass.
The first pipe 25 and the second pipe 27 can be defined by the separation panel 30 installed in the technical compartment 13 to separate the latter into two portions, that is, the first pipe 25 and the second pipe 27.
The separation panel 30 can be made with a heat insulating material, thus preventing the possible thermal heating energy, provided for example for defrosting the evaporator 23, from also heating the eutectic container 28 as well, decreasing its efficiency.
According to one aspect of the present invention, the second pipe 27 is positioned in direct proximity to the support structure 15, that is, in a position closer to the food products. This position prevents excessive cooling of the food products during the refrigeration step, or their heating during the defrosting step.
According to a first variant embodiment, shown by way of example in fig. 1, the refrigerated display case 10 comprises at least one fan 31 installed in the technical compartment 13 and configured to selectively generate a first flow of air through the first circuit 26 and a second flow of air through the second circuit 29.
According to this solution, at least one flow divider member 32 can be installed in the technical compartment 13, configured to allow and/or prevent the passage of the flow of air through the first pipe 25 or through the second pipe 27, and therefore to interrupt the first circuit 26 and/or the second circuit 29.
In particular, it is possible to provide a single flow divider member 32 installed in correspondence with the first pipe 25 and the second pipe 27 and configured to allow the air to pass through the first pipe 25 and to prevent it through the second pipe 27, or vice versa.
According to a variant embodiment, not shown, both the first pipe 25 and the second pipe 27 are provided with a respective divider member 32.
The divider member 32 can comprise a reed valve or a non-return valve.
According to the solution shown in fig. 1, the first pipe 25 and the second pipe 27 are provided with an inlet end 33 and an outlet end 34 through which the flow of air is respectively introduced and discharged.
According to a possible solution, shown for example in fig. 1, the divider member 32 is installed in correspondence with the inlet ends 33 of the first pipe 25 and the second pipe 27.
According to the embodiment shown in fig. 1, a single fan 31 is installed in the technical compartment 13, cooperating with the divider member 32 to selectively generate the flow of air either in the first circuit 26 or in the second circuit 29. This allows to reduce the overall costs of the refrigerated display case 10.
According to a possible solution, the single fan 31 is installed in correspondence with the outlet end 34 of the first pipe 25 and the second pipe 27, thus generating a flow through the evaporator 23 or toward the eutectic container 28 through air suction. However, it is not excluded that the fan 31 can be installed in correspondence with the inlet end 33 of the first pipe 25 and the second pipe 27.
In the normal functioning of the refrigerated display case 10, the divider member 32 is put to close the second pipe 27, or in this specific case, it occludes the inlet end 33 of the latter. In this way the flow of air is prevented towards the eutectic container 28 and therefore through the second circuit 29.
During this step, the eutectic container 28 accumulates thermal cooling energy, for example by heat convection.
The accumulation of heat energy in the eutectic container 28 can take place quite slowly, for example within a time range comprised between about 2 and 4 hours, that is, the rate at which the defrosting is performed. The slow accumulation of energy avoids overloading the refrigeration plant 14 during its normal functioning.
The fan 31 is driven to generate a flow of air through the first circuit 26.
When defrosting of the evaporator 23 is required, the divider member 32 is positioned to close the first pipe 25, or in this specific case to close the inlet end 33 of the latter.
The fan 31 thus generates a flow of air that passes through the second circuit 29, while the divider member 32 prevents its passage through the first pipe 25.
In this condition, the defrosting device 24 is activated to defrost the evaporator 23.
The defrosting lasts only a few minutes, for example comprised between about 5 and 10 minutes.
According to the variant embodiment shown in fig. 2, the refrigerated display case 10 comprises a first fan 131 installed in the first pipe 25 and a second fan 135 installed in the second pipe 27, configured to generate respectively a first flow of air through the first circuit 26 and a second flow of air through the second circuit 29.
According to this solution, it can be provided that the first fan 131 and the second fan 135 are installed in correspondence with the respective outlet ends 34 of the first pipe 25 and the second pipe 27. This positioning of the fans 131, 135 allows to obtain an efficient heat exchange through the evaporator 23 and respectively through the eutectic container 28.
According to a variant embodiment, the first fan 131 and the second fan 135 can be installed in correspondence with the inlet end 33 of the first pipe 25 and/or the second pipe 27.
According to the embodiment shown in fig. 2, the refrigerated display case 10 may not have the divider member 32, although it is not excluded that in possible embodiments the divider member 32 may be present.
According to the solution shown in fig. 2, during the normal functioning of the refrigerated display case 10 it is provided that the evaporator 23 and the first fan 131 are activated while the second fan 135 is deactivated, thus allowing the generation of a flow of air through the first circuit 26 and preventing it through the second circuit 29.
When it is required to defrost the evaporator 23, the first fan 131 is deactivated and the defrosting device 24 and the second fan 135 are driven.
In this way, in the second circuit 29 a flow of air is generated that hits the eutectic container 28 while the passage of air through the evaporator 23 is prevented, to prevent any moisture generated during the defrosting of the latter from circulating to the display compartment 11.
According to another solution of the present invention it is provided that at least the second pipe 27, in which the eutectic container 28 is installed, is installed inclined, so that the outlet end 34 is in a lower position than the inlet end 33. This positioning allows an easy outflow of the possible condensation that is generated in the second pipe 27.
According to possible variant embodiments, not shown in the drawings, it can be provided that the eutectic container 28 is also associated with a defrosting circuit, for example in the second pipe 27. This defrosting action of the eutectic container 28 can be performed less frequently than that of the evaporator 23, for example once every 2-3 days.
According to other solutions of the present invention, the refrigerated display case 10 can be provided with sensors configured to detect the temperature in the display compartment 11 and adjust, for example, the functioning modes of the refrigeration plant and/or fans 31, 131, 135.
According to other embodiments, the refrigerated display case 10 can be provided with sensors to detect the formation of ice, configured to detect the presence of ice in the evaporator 23.
According to possible solutions, the sensors to detect the formation of ice can be electrically connected to a control and command unit configured to manage the functioning of the evaporator 23, the divider member 32 and the at least one fan 31, 131, 135 according to one or other of the above methods.
It has been found experimentally that, even if the solution with one fan 31 and a divider member 32 is effective and satisfies the purposes of the invention, the variant in fig. 2, in which two fans 131 and 135 are provided, is substantially cheaper and has more advantages than those obtainable with the divider member 32 and one fan 31.
For example, in certain situations where it is not used for long periods, the divider member 32 runs the risk of icing over and therefore of remaining blocked in one position or another.
Furthermore, the divider member 32 can clearly open one pipe at a time, hence either pipe 25 or pipe 27.
According to another step of the present refrigeration method, on the contrary, it can be extremely useful and advantageous that for a given period of time, for example a few minutes, the two pipes 25 and 27 are simultaneously active, that is, the air flows simultaneously in both pipes 25 and 27.
The simultaneous delivery of air in both pipes 25 and 27 can advantageously be performed by simultaneously switching on the two fans 131 and 135.
For example, at the end of defrosting, the evaporator 23 could be at a temperature comprised between 10°C and 20°C, and therefore the compressor of the refrigeration plant 14 is restarted in order to restore its function as a cold generator. The fan 131 of the evaporator 23 remains switched off until the temperature of the evaporator 23 falls to about -2°C. When the fan 131 of the evaporator 23 is switched on, the fan 131 of the eutectic container 28 should not be switched off again, at least for a few minutes, because the temperature of the eutectic container 28 is still lower than the temperature of the evaporator 23.
It is therefore desirable for the fans 131 and 135 to function together for a certain period of time, for example a few minutes, until the evaporator 23 reaches a lower temperature than that of the eutectic container 28, for example between about -16°C and -18°C.
When the temperature of the evaporator 23 drops below the temperature of the eutectic container 28, the fan 135 of the eutectic container 28 can be switched off and the eutectic container 28 can be recharged in a subsequent period of time, for example between 2 and 4 hours, which is enough time for it to be ready for a new defrosting cycle.
It is therefore advantageous that in one step of the present refrigeration method, both fans 131 and 135 remain switched on simultaneously for a certain period of time.
It is clear that modifications and/or additions of parts and/or steps can be made to the refrigerated display case 10 and to the corresponding refrigeration method described heretofore, without departing from the field of the present invention.
For example, the refrigerated display case 10 can be structured differently from the embodiments shown in figs. 1 and 2, for example, it can be oriented vertically to create a refrigerated wall display case.
It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other forms of refrigerated display case 10 and corresponding refrigeration method, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

Claims

Refrigerated display case comprising a display compartment (11) for food products and a technical compartment (13), separate from said display compartment (11) and located in fluidic communication with the latter, at least one evaporator (23) of a refrigeration plant (14) being installed in said technical compartment (13), a defrosting device (24) being associated with said evaporator (23) to defrost said evaporator (23), said technical compartment (13) comprises:
- a first pipe (25) in which said evaporator (23) is installed and defining with said display compartment (11) a first circuit (26) for the passage of the air, and comprising at least one fan (31,131,135), installed in said technical compartment (13) and configured to selectively generate a flow of air through said first circuit (26) or through a second circuit (29),
characterized by
- a second pipe (27) in which a eutectic container (28) made of deformable plastic material is installed and defining with said display compartment (11) said second circuit (29) for the passage of the air, wherein said eutectic container (28) comprises opposite walls formed by undulating profiles (36, 37) able to create ample heat exchange surfaces and wherein the deformable plastic material of which the eutectic container (28) is made also allows it to suitably adapt to the dilations due to the temperature variations of the eutectic solution.
Refrigerated display case as in claim 1, characterized in that said undulating profiles (36, 37) comprise ridges (39) to support the eutectic container (28).
Refrigerated display case as in claim 1, characterized in that said eutectic container (28) is modular and formed by a plurality of eutectic modules.
Refrigerated display case as in claim 1, characterized in that it comprises a first fan (131) installed in said first pipe (25) and a second fan (135) installed in said second pipe (27), configured to generate respectively a first flow of air through said first circuit (26) and a second flow of air through said second circuit (29).
Refrigerated display case as in any claim hereinbefore, characterized in that at least one stream divider member (32) is installed in said technical compartment (13), configured to allow and/or prevent the passage of the flow of air through said first pipe (25) or through said second pipe (27).
Refrigerated display case as in claim 5, characterized in that it comprises a single fan (31) installed in said technical compartment (13) and cooperating with said divider member (32) to selectively generate the flow of air either in said first circuit (26) or in said second circuit (29).
Method to refrigerate food products contained in a display compartment (11) of a refrigerated display case as in any claim hereinbefore, that provides:
- to activate an evaporator (23) of a refrigeration plant (14) to cool a flow of air circulating between said display compartment (11) and a technical compartment (13), in which said evaporator (23) is installed,

- to defrost said evaporator (23) using a defrosting device (24),
characterized in that
during the activation of said evaporator (23) the generation of a first flow of air is provided through a first circuit (26) for the passage of the air defined between said display compartment (11) and a first pipe (25) of said technical compartment (13) in which said evaporator (23) is installed, and in that during the defrosting of said evaporator (23) the generation of a second flow of air is provided through a second circuit (29) for the passage of the air defined between said display compartment (11) and a second pipe (27) in which a eutectic container (28), made of a deformable plastic material, is installed and able to supply refrigeration energy, said first flow of air and said second flow of air being generated by at least one fan (31; 131, 135) installed in said technical compartment (13), wherein said eutectic container (28) comprises opposite walls formed by undulating profiles (36, 37) able to create ample heat exchange surfaces and wherein the deformable plastic material of which the eutectic container (28) is made also allows it to suitably adapt to the dilations due to the temperature variations of the eutectic solution.
Method as in claim 7, characterized in that said first flow of air is generated by the activation of a first fan (131) installed in said first pipe (25), and in that said second flow of air is generated by the activation of a second fan (135) installed in said second pipe (27).
Method as in claim 7, characterized in that it comprises at least a simultaneous switching-on step of said first fan (131) and said second fan (135).
Method as in claim 7, characterized in that during the activation of said evaporator (23) a divider member (32) is located to close said second pipe (27) and in that during the defrosting of said evaporator (23) said divider member (32) is located to close said first pipe (25).