DESCRIPTION «PLANT FOR THE PRODUCTION OF ICE CREAM"

[0001] A plant for the production of ice cream forms the object of the present invention, in particular a plant capable of producing a high quantity of ice cream of packaged type, such as ice cream in cartons, ice cream cones, ice cream on sticks or the like.

[0002] In plants for the production of ice cream, the ingredients necessary for the preparation of the ice cream are treated according to several successive stages, generally corresponding to a multiplicity of working stations. In particular, the ice cream production plants comprise one or more inlets for the ingredients, one or more stations for the treatment of such ingredients (more specifically, for their mixing, eventually with the addition of air, and for their cooling) , and a packaging station, for example in containers or cases of the formed ice cream. [0003] In plants for the production of high quantities of ice cream, a plurality of production lines are provided, placed in parallel, which carry out all or some of the above-described operations.

[0004] Regarding the refrigeration system for the cooling of the ingredient mixture, two different solutions are known.

[0005] According to a first of such two solutions, in each of the production lines an autonomous refrigeration unit is provided which executes a thermodynamic refrigeration cycle by operating on a refrigerating fluid. Each refrigeration unit comprises a compressor, an evaporator and a condenser.

[0006] The evaporator of the refrigeration unit is usually an exchanger cylinder in which the ingredient mixture which must be cooled is arranged. Such evaporator has the function of making possible the transfer of heat from the ingredient mixture to the refrigerating fluid treated by the refrigeration unit for the refrigeration cycle . [0007] The condenser of the refrigerator unit has the function of making possible the transfer of heat by the refrigerating fluid to an additional carrier fluid, usually water, which is sent to an evaporation tower after the heating due to the heat exchange with the refrigerating fluid itself. [0008] In accordance with a second of such two solutions, the refrigeration unit is instead centralised, and the refrigerating fluid is sent from this unit to each cooling portion, refrigerating fluid subjected to the refrigeration cycle of the refrigerator unit itself. Each exchanger cylinder functions as evaporator of the

refrigeration cycle.

[0009] In both described solutions, the refrigerating fluid used is ammonia or one of the so-called Freons . [0010] Such ice cream production plants according to the prior art are not, however, free of drawbacks.

[0011] Since every refrigeration unit is equipped with its own compressor, the environment in which the production lines are provided is characterised by considerable noise. [0012] Moreover, the presence of compressors in each production line leads to further undesirable bulk along the single production lines, and therefore the need for spacious environments in order to be able to obtain a high productive capacity of the plant. [0013] When the refrigeration unit is centralised, there is a considerable reduction of the overall bulk of the production lines, each of which lacks its own autonomous refrigeration unit. Nevertheless, a very reliable tubing system is necessary for the transportation of the ammonia or the Freon, in order to avoid their accidental loss, which is potentially very dangerous. In fact, the ammonia has a high volatility and toxicity and is therefore extremely polluting if dispersed in the environment. The Freons, on the other hand, are held co- responsible for the so-called hole of the ozone layer.

[0014] Finally, in both of the described solutions, the choice of the refrigerating fluid is set by the needs of the refrigeration unit. For this reason, ammonia or Freons are chosen, which are optimal for carrying out refrigeration cycles, but as said have a strong environmental impact. Moreover, such refrigerating fluids have the property of evaporating at least in part at low temperatures (in certain conditions also below 0 ⁰ C) and it is therefore very complex to control their flow rate with precision during their movement to the cooling portions.

[0015] Object of the present invention is therefore that of making available an ice cream production plant which ensures a low risk of accidental loss of high environmental impact fluids, and is equipped with a distribution system of the refrigerating fluid whose properties can be at least partially freed from the technical needs dictated by the refrigeration system. [0016] These and other objects are achieved by means of a plant for the production of ice cream which comprises:

[0017] - one or more lines for the ice cream production which comprise a cooling portion suitable for the cooling of a mixture of ice cream ingredients; [0018] - a distribution circuit suitable for sending a refrigerating fluid to each of these cooling portions;

[0019] - a refrigeration unit for the cooling of the refrigerating fluid,

[0020] wherein the distribution circuit is fluidly independent from the refrigeration unit and in a heat exchange relationship with it, so that the refrigerating fluid can transfer heat to the refrigeration unit and thus be cooled.

[0021] To better understand the invention and appreciate its advantages, several exemplifying and non-limiting embodiments are described, making reference to the attached figures, wherein:

[0022] Figure 1 is a schematic view of a ice cream production plant according to the invention; [0023] Figure 2 is a side schematic view of a detail of the ice cream production plant of figure 1.

[0024] With reference to the figures, a plant for the production of ice cream, in particular a plant for the production of a high quantity of ice cream, is indicated with the reference number 1. [0025] The plant 1 comprises one or more lines 2 for the production of ice cream. Such production lines 2 are preferably arranged in parallel. These production lines can be suitable for producing the same type of ice cream, or different types of ice cream, such as for example packaged ice creams, ice cream cones, ice cream

on sticks, or the like. Each production line 2 can moreover be activated or deactivated independent of the others according to need.

[0026] Each of these production lines 2 can comprise one or more portions 3, preferably arranged in series with each other, each of which suitable for executing one or more separate operations .

[0027] For example, each production line 2 can comprise one or more of the following portion types 3 : [0028] - an inlet portion, in which the ingredients can be inserted which are necessary for the formation of the ice cream;

[0029] - a mixing portion, in which such ingredients can be mixed with each other; [0030] - a working portion, in which the ingredients can be worked in a suitable manner for forming the final ice cream, for example by means of continuous mixing of the ingredient mixture;

[0031] - a packaging portion in which the produced ice cream is packaged, for example in containers, cases or the like.

[0032] During operation, or when the plant 1 is in function for the production of ice cream, it is necessary to cool the ingredient mixture. To such end, each production line 2 comprises a cooling portion 4.

[0033] Each cooling portion 4 is fluidly connected to a distribution circuit 5 having the function of sending a refrigerating fluid to the cooling portions 4 themselves, so that the latter are capable of cooling the ice cream ingredient mixture.

[0034] The plant 1 moreover comprises a refrigeration unit 6 having the function of cooling the refrigerating fluid in the distribution circuit 5, so that this can reach the cooling portions 4 at an adequately low temperature for the cooling of the ingredient mixture.

[0035] Advantageously, the distribution circuit 5 is fluidly independent from the refrigeration unit 6 and is moreover placed in a heat exchange relationship with it. In this manner, during operation, the refrigerating fluid intended to reach the cooling portions 4 can transfer heat to the refrigeration unit 6 and hence be cooled.

[0036] In other words, the refrigeration unit 5 and the distribution circuit 4 are configured so to not have reciprocal exchange of refrigerating fluid. The refrigerating fluid which during operation circulates in the distribution circuit 5 is not treated in the refrigeration unit 6, but exchanges heat with this. Preferably, the refrigerating fluid of the distribution circuit 5 exchanges heat with a work fluid treated by

the refrigeration unit 4 itself, still more preferably a work fluid different from the refrigerating fluid. [0037] Consequently, it is possible to provide a centralised refrigeration unit 6 and therefore obtain a considerable advantage in terms of overall bulk of the plant 1.

[0038] Moreover, the refrigerating fluid of the distribution circuit 5 can be chosen independently of the technical needs of the refrigeration unit 6, since it does not have to be treated directly by the latter, for example in a refrigeration cycle. Refrigerating fluids with high environmental impact, such as ammonia and Freon, can thus be avoided, consequently eliminating the risk of a loss thereof by the tubing of the distribution circuit 5.

[0039] Preferably, the refrigeration fluid has characteristics such to remain substantially in the liquid state during plant operation, in particular in the work temperature range. In this manner it is possible to precisely control its flow rate circulating in the distribution circuit 5.

[0040] In accordance with one embodiment, the distribution circuit 5 is suitable for transporting a refrigerating fluid chosen from the glycol group. This type of refrigerating fluid has the further advantage of being

able to circulate in sanitary tubing, suitable, for example, for the transport of water, rather than in tubing made expressly for ammonia or the Freons, which must ensure an extremely high seal, also with regard to the exit of gas .

[0041] Advantageously, the refrigeration unit 6 is configured in such a manner so to be capable of executing a thermodynamic refrigeration cycle on its work fluid. Such work fluid, being separate and independent from the refrigerating fluid of the distribution circuit 5, can be chosen with characteristics suitable for its use in a refrigeration cycle. Preferably, the work fluid is ammonia or is chosen from the Freon group. Such fluids are suitable, for example, for refrigerating cycles of reversed Rankine type, or cycles combined with it, for their state characteristics, in particular for the temperatures at which they are capable of evaporating. [0042] Since the refrigeration unit 6 is separate from the distribution circuit 5 and does not exchange fluid with it, the work fluid is treated only in the refrigeration unit 6, without being distributed to the production lines 2. The risk of accidental loss of work fluid is therefore extremely low since it is confined in a limited portion of the plant 1, without having to pass

through long tubing for its distribution up to the cooling portions. This fact involves the further advantageous possibility that limited quantities of fluids with high environmental impact can be used, for example quantities which are lower with respect to the case of refrigeration units provided in each production line.

[0043] Advantageously, in order to make the mentioned heat exchange relationship between the refrigeration unit 6 and the distribution circuit 5, the plant 1 comprises one or more heat exchangers 7 operatively connected therewith. Such heat exchangers 7 are configured in a manner such to avoid the mixing of the work fluid of the refrigeration unit 6 and the refrigerating fluid of the distribution circuit 5.

[0044] In accordance with one embodiment, the heat exchangers 7 function as evaporators for the refrigeration unit 6, i.e. they serve to ensure that the work fluid subjected to the refrigeration cycle at least partially evaporates due to the absorption of heat from the refrigerating fluid of the distribution circuit 5. [0045] In accordance with a further embodiment, the refrigeration unit 6 comprises one or more condensers 30 suitable for making the work fluid transfer heat to a further external device 31. Preferably such external

device 31 comprises a tubing system configured to send a carrier fluid, for example water, to an evaporating tower (not shown in the figures) connected to the plant 1. [0046] Advantageously, the plant 1 comprises accumulation means 8 operatively connected to the distribution circuit 5. Such accumulation means 8 , for example one or more tanks connected with each other, have the function of storing the refrigerating fluid in a quantity suitable for supplying the cooling portions 4 of the production lines 2. The accumulation means 8 moreover have the advantageous function of heat accumulators, i.e. in other words they have the function of maintaining the refrigerating fluid at an adequately low temperature so that once it has reached the cooling portions 4, it is capable of cooling the mixture of ingredients for ice cream. For this purpose, the accumulation means 8 are heat insulated, so to thermally insulate the refrigerating fluid at their interior as much as possible.

[0047] Advantageously, the accumulation means 8 are arranged in the distribution circuit 5 so to subdivide it into two separate portions having in common the accumulation means 8 themselves, which therefore act as a refrigerating fluid reserve for both of these two

portions .

[0048] In accordance with one embodiment, a first of these two distribution circuit portions is a heat exchange portion 9 suitable for making the aforesaid heat exchange relationship between the refrigeration unit 6 and the refrigerating fluid, and a second of these two distribution circuit portions is a sending portion 10 suitable for sending the refrigerating fluid to the cooling portions 4 of the production lines 2. [0049] Advantageously, each of these two portions 9 and 10 of the distribution circuit 5 forms a closed circuit together with the accumulation means 8, closed circuit suitable for recirculating the refrigerating fluid. To ensure that the refrigerating fluid is capable of recirculating in the heat exchange portion 9 and in the sending portion 10, the distribution circuit 5 can comprise means 25 for recirculating the refrigerating fluid, for example one or more recirculation pumps. [0050] The heat exchange portion 9 of the distribution circuit 5 is at least in part arranged and configured so that the refrigerating fluid which flows therein can transfer heat to the refrigeration unit 6, in particular to its work fluid. To such purpose, the heat exchangers 7 are advantageously arranged in the heat exchange portion 9.

[0051] During operation, the refrigerating fluid, coming through an opening 11 from the accumulation means 8, reaches the heat exchangers 7, in which it enters through an opening 12. The refrigerating fluid then exits through an opening 13 from the heat exchangers 7 at a lower temperature than it had at the entrance, due to the transfer of heat to the refrigeration unit 6. The refrigerating fluid is then sent once again to the accumulation means 8, in which it enters by means of an opening 14.

[0052] Due to the described recirculating of the refrigerating fluid between the accumulation means 8 and the heat exchangers 7, it is ensured that the refrigerating fluid inside the accumulation means 8 is maintained within adequate temperature values for cooling the ingredient mixture in the cooling portions 4.

[0053] Advantageously, the sending portion 10 of the distribution circuit 5 comprises an outgoing side 15 and a return side 16, interconnected with each other. The outgoing side 15 serves for sending the refrigerating fluid to each of the cooling portions 4 of the production line 2 from the accumulation means 8, which have an opening 17 for such connection. The return side 16 has the function of conveying the refrigerating fluid

coming from the cooling portions 4 to the accumulation means 8, into which it can enter through an opening 18. [0054] During operation, the refrigerating fluid which flows in the return side 16 is at a higher temperature than the refrigerating fluid which flows in the outgoing side 15, since in the cooling portions 4 it is used for cooling the ice cream ingredient mixture, and thus it is heated. Consequently, such refrigerating fluid increases the temperature of the fluid accumulated in the accumulation means 8, temperature which is however advantageously maintained within right limits due to the recirculation of refrigerating fluid which occurs in the heat exchange portion 9. [0055] Advantageously, each of the cooling portions 4 comprises an exchanger device 19 which is suitable for containing the ingredient mixture for the ice cream therein and for putting the mixture in a heat exchange relationship with the refrigerating fluid. Due to such heat exchange relationship, the refrigerating fluid can absorb heat from the ingredient mixture, and thus cool the mixture.

[0056] In accordance with one embodiment, the exchanger device 19 is arranged so to be able to receive from the outgoing side 15 the refrigerating fluid coming from the accumulation means 8, and to be able to send back to the

return side 16 the refrigeration fluid which flew in the exchanger device. In this manner, the functioning of each cooling portion 4 does not condition the functioning of the cooling portions 4 of the other production lines 2, since the refrigerating fluid exiting from each of these returns directly to the accumulation means 8.

[0057] The exchanger devices 19 of each cooling portion 4 are connected to the distribution circuit 5 preferably in two points. In particular, each exchanger device 19 can be connected to the outgoing side 15 by means of an opening 20 and to the return side 16 by means of an opening 21. [0058] In accordance with one embodiment, the connection between the outgoing side 15 and the exchanger device 19 at the opening 20 and the connection between the return side 16 and the exchanger device 19 at the opening 21 are made through removable connection means (not shown in the figures) . In this manner, according to need, it is possible to connect or disconnect the cooling portions 4 of one or more production lines 2 from the distribution circuit 5.

[0059] Such removable connection means can moreover comprise sealing means, so that both the distribution circuit 5 and the cooling portions 4 do not have

refrigerating fluid leaks when they are disconnected. For example, the connection can be carried out with quick coupling connectors, which ensure both removability and the seal in case of disconnection. [0060] Advantageously, the exchanger device 19 comprises a freezer cylinder 26 having a chamber 27 at its interior suitable for receiving the mixture of ice cream ingredients (figure 2) . [0061] Such inner chamber 27 can moreover be fed by an air flow to be mixed with the ingredients, provided by a pumping group (not shown in the figures) . [0062] In accordance with one embodiment , with plant 1 ready for use, such freezer cylinder 26 is arranged in a tilted position with respect to the ground, so that the mixture of ingredients can be concentrated in the portion of the inner chamber which is closest to the ground, without being spread in the entire inner chamber 27. Such tilting of the freezer cylinder 26 has the further advantage of simplifying the cleaning and maintenance operations .

[0063] For the production of ice cream, it may be necessary that the ingredient mixture inside the freezer cylinder 26 is maintained in movement. For such purpose, the freezer cylinder 26 can comprise a stirrer 28, preferably equipped with scraping blades (not shown in

the figures) , suitable for mixing the ingredients inside the inner chamber 27. The stirrer 28 can be driven by a motor 29, for example an electric motor. [0064] Advantageously, each cooling portion 4 of the production lines 2 comprises at least one adjustable regulation valve 22 placed in fluid communication with the exchanger device 19, so to regulate the flow rate of refrigerating fluid passing through it and consequently the amount of the heat exchange with the ingredient mixture (figure 1) .

[0065] With reference to the flow direction of the refrigerating fluid during operation (indicated as example with the arrows of figure 1) , the regulation valve 22 can be placed upstream or downstream of the exchanger device 19.

[0066] In accordance with one embodiment, the regulation valve 22 is an adjustable mixing valve suitable for mixing in a variable manner the refrigerating fluid flows destined for the exchanger device 19 and for a by- pass line 23 placed in parallel with the exchanger device 19.

[0067] Preferably, the regulation valve 22 is arranged downstream of the exchanger device 19 as well as the bypass line 23, at the point in which these are fluidly connected .

[0068] The regulation valve 22 is advantageously- configured so to be able to divide the refrigerating fluid flow coming from the outgoing side 15 of the distribution circuit 5 in a variable manner between the by-pass line 23 and the exchanger device 19. The regulation valve 22 is moreover capable of conveying the entire flow either in the by-pass line 23 or into the exchanger device 19. [0069] For the control of the functioning of such regulation valve 22 , the plant 1 advantageously comprises a control system 24 for regulating the opening of the regulation valve 22 as a function of the temperature present in the inner chamber of the freezer cylinder 26, in which the ingredient mixture is housed. Such temperature can be read and sent to the control system 24 by one or more temperature sensors (not shown in the figures) .

[0070] If the temperature in the inner chamber 26 exceeds the optimal value necessary for the formation of the ice cream, the control system 24 acts such that the regulation valve 22 produces an increase of the refrigerating fluid flow rate in the exchanger device 19 and a decrease of the refrigerating fluid flow rate in the by-pass line 23. [0071] On the other hand, if the temperature in the inner

chamber is lower than the optimal value, the control system 24 acts such that the regulation valve 22 produces a decrease of the refrigerating fluid flow rate in the exchanger device 19 and an increase of the refrigerating fluid flow rate in the by-pass line 23.

[0072] The skilled person can appreciate from the above description how the plant for the production of ice cream according to the invention resolves the main problems connected with plants for the production of ice cream according to the prior art.

[0073] In particular, the skilled person will appreciate how in the plant according to the invention the potentially dangerous fluids, i.e. fluids, such as ammonia or Freons, necessary for the execution of refrigeration cycles, are confined in one portion of the plant, in particular at the refrigeration unit, and do not have to be distributed to all production lines. Consequently, the risk of an accidental loss thereof is extremely reduced. [0074] Moreover, the skilled person can appreciate how in the plant according to the invention it is possible to choose the refrigerating fluid to send to the production lines independently of the needs dictated by the functioning of the refrigeration unit . It is therefore possible to choose a fluid which remains substantially

in the liquid state at the work temperatures of the plant, which permits an easy regulation of the flow rates, which is instead more complex and more imprecise in the case of two-phases refrigerating fluid. The substantial absence of fluids in the vapour state further reduces the risk of their accidental leak into the environment .

[0075] Finally, the skilled person can appreciate how the system according to the invention adds to the aforesaid advantages that of having overall reduced bulk, since it is possible to use the same refrigeration unit for all production lines.

[0076] The skilled person can make numerous adaptations and modifications to the above-described embodiments of the ice cream production plant according to the invention, as well as substitutions of elements with other functionally equivalent elements, without however departing from the scope of the following claims.