DESCRIPTION

Technical Field

The present invention refers in general to vending machines, in particular of the type intended to be installed in communities, such as workplaces or health facilities, or in open places, such as railway stations. The invention has been developed with particular attention being paid to vending machines intended to dispense at least coffee-based beverages in cup containers, typically cups supplied by the same vending machine.

State of the art

Vending machines of the indicated type are widely known. Some of these vending machines are designed for preparing on spot coffee-based beverages - such as an espresso coffee - starting from coffee beans.

For this purpose, inside a cabinet of the vending machine the various components or functional units are housed, that allow to obtain the beverage and which typically comprise:

- a storage volume, usually consisting of a hopper container, for containing the coffee beans;

- a grinder, set downstream of an outlet of the storage volume, designed to grind coffee beans from the storage volume;

- a brewing unit, set downstream of an outlet of the grinder, designed to receive an amount of ground coffee from the grinder, this amount being usually dosed by the same grinder (grinder-doser);

- a supply arrangement, configured for supplying an extraction fluid, such as hot water, to the brewing unit, this arrangement generally including a water source (such as a drinking water tank, or a connection to an external drinking water network) and a boiler;

- a dispensing arrangement of the coffee-based beverage, set downstream of an outlet of the brewing unit, typically including a nozzle that dispenses the beverage at a suitable pick-up area outside the cabinet of the vending machine.

Clearly, the vending machine preferably includes other functional elements or units, such as one or more storage volumes of other beverage precursors (as those schematized in 10’ in figure 1), or a store configured for the storage of cups and the selective positioning thereof at the aforementioned pick- up area, a control system including a control unit, etc., which are not, however, of immediate interest for the understanding of the problems underlying the invention.

In the vending machines of this type, following the request from a user, entered via a suitable user interface, the grinder grinds a certain amount of coffee beans coming from the storage volume, in order to produce a dose of ground coffee that is fed to the brewing unit, to which a certain amount of hot water is also fed via the supply arrangement. The brewing unit prepares the beverage through the interaction between the dose of ground coffee and the hot water, with this beverage that - through the dispensing arrangement - is supplied outside the vending machine cabinet.

The environment in which the vending machine is installed can assume high values of temperature, and possibly of humidity. Think of a vending machine installed outdoors, for example in a railway station, where the summer environmental temperature can attain values above 30°C. Consider also that various internal electrical components of the vending machine - such as one or more motors or the boiler for heating water - are themselves a source of heat. In such circumstances, inside the vending machine cabinet, a temperature of 40-50°C can be easily reached, as well as significant humidity rate, even above 60%.

These particularly severe conditions inside the vending machine cabinet adversely affect the quality of the raw material of the beverage, for example, due to oxidative phenomena and loss of volatiles, which occur when the coffee beans are exposed to high levels of temperatures and humidity. This deterioration of the coffee beans evidently brings about a deterioration of the quality of the dispensed beverage, for example in the taste thereof. Similar problems may also occur in relation to other beverage precursors, for example precursors already in granular or powdery form, such as soluble preparations or preparations for infusions.

It should be noted that some automatic machines for household use are equipped with a container for the storage of coffee beans, as well as of a grinder, for operating in a way substantially similar to that described above. DE 101 47 284 A disclsoes one such automatic machine for household use, equipped with an arrangement for cooling the storage container of the coffee beans and the grinder. The cooling arrangement consists of a series of Peltier elements and the machine is designed in such a way that, just before the start of a grinding process, the Peltier cells are activated until the coffee beans are cooled to a predetermined temperature, between -25 and -40 ⁰ C. This prior solution ensures that the grinding process takes place at a temperature at which the taste of the coffee beans is guaranteed to be maintained. However, this solution does not appear suitable for use in a vending machine of the type indicated above, in particular when intended for use in open places, also for reasons of low heat exchange efficiency.

Aim and summary

In its general terms, the present invention aims to obtain a vending machine of the type indicated at the beginning, able to efficiently solve the drawback indicated above, tied to the possible existence of a high temperature and/or humidity inside the cabinet of the vending machine.

This aim is attained, according to the invention, by a vending machine having the characteristics indicated in the attached claims. The claims form an integral part of the technical teaching provided herein in relation to the invention.

Brief description of the drawings

Further aims, characteristics and advantages of the invention will result from the following description, made with reference to the attached drawings, provided by way of non-limiting example only, wherein:

- figure 1 is a schematic representation of a vending machine according to possible embodiments of the invention;

- figure 2 is a schematic representation of some internal elements of a vending machine according to possible embodiments of the invention;

- figures 3-7 are schematic representations of some internal elements of a vending machine according to variant embodiments of the invention; and

- figure 8 is a schematic representation of a vending machine according to a possible variant embodiment of the invention.

Description of preferred embodiments

Reference to “an embodiment” or “one embodiment” in the framework of the present description is intended to indicate that a particular configuration, structure, or characteristic described in relation to the embodiment is comprised in at least one embodiment. Hence, phrases such as “in an embodiment”, “in one embodiment, “in various embodiments”, and the like, that may be present in different points of this description, do not necessarily refer to one and the same embodiment. Furthermore, particular conformations, structures, or characteristics defined in the framework of the present description may be combined in any adequate way in one or more embodiments, that may even differ from the ones represented. The reference numbers and spatial references (such as “upper”, “lower” “top”, “bottom”, etc.) used herein are merely for convenience and hence do not define the sphere of protection or the scope of the embodiments. The same reference numbers are used in the figures to indicate similar or technically equivalent elements.

Referring initially to Figure 1, reference 1 indicates as a whole a vending machine, in particular of the type designed to be installed in communities, such as workplaces or health facilities, or in open places, such as railway stations. The vending machine 1 is configured to dispense at least coffee-based beverages, not excluding with this that the machine can be configured - in a way known in itself - to provide other food products in solid form, preferably packaged products (for example brioches or snacks), and/or other types of beverages (for example tea, or milk, or similar), in particular beverages obtainable from soluble precursors.

The vending machine 1 comprises a cabinet 2, for example having a substantially parallelepiped shape, preferably having a metal supporting structure, possibly completed with plastic panels. Preferably, at least one side of the cabinet 2 comprises or obtain a door, in order to allow access to the inside of the cabinet itself. In various embodiments, at a front of the cabinet 2, a user interface 3 is provided, through which a user can set the request for a product that can be dispensed by the vending machine 1. This interface 3 may comprise, for example, a display and a set of selection keys, as well as a possible payment device, comprising for example a slot for introduction of coins and/or a system for introduction of banknotes and/or a socket for inserting an electronic payment key and/or an electronic contactless payment system.

Preferably, always at the front of cabinet 2, at least one pick-up area 4 for the products dispensable by the vending machine is defined. This pick-up area 4 may comprise, for example, a space defined at the front of cabinet 2, which is accessible from outside the cabinet itself. In preferential embodiments of the invention, the vending machine 1 comprises inside a store for the storage of cups, for example cups made of plastic or paper material, and a handling system for placing in advance a single cup C at the pick-up area 4, to receive a beverage that have to be dispensed. The aforementioned store and the corresponding cup positioning system are not tied to the purposes of the invention and can be obtained in any ways known per se in the field.

Inside the cabinet 2 various components or functional units are housed, that enable to obtain a coffee-based beverage, for example, an espresso coffee. With 10 a storage volume is indicated, for containing coffee beans. With I l a grinder 11 is indicated, configured to grind coffee beans fed by the volume 10; the design and the way of operation of the grinder 11 can be of any known type, the grinder being preferably configured, or having associated a system, for the dosage at input of a dosed amount of coffee beans, or else for the dosage at output of a predefined amount of ground coffee. Reference 12 designates a brewing unit, also of a known conception, prearranged for receiving the aforementioned amount of ground coffee from the grinder 11, dosed by the grinder itself or by the associated dosing system. With 13 a known supply arrangement is indicated, prearranged for feeding an extraction fluid to the brewing unit 12.

In view of preparing the coffee-based beverage, e.g., an espresso coffee, the extraction fluid may be hot water, and for this purpose the arrangement 13 comprises, for example, a source of drinking water, such as a tank that can be periodically topped-up, as well as a device for heating the water to be supplied to the brewing unit 12, for example, a known electric boiler. To this end, the arrangement 13 preferably also includes means for dosing the water to be delivered to the brewing unit 12, comprising for example a volumetric meter (such as an impeller meter) and at least one solenoid valve. Note that the drinking water source may include a supply network outside the cabinet 2, in which case the arrangement 13 includes a suitable connection to such an external network, preferably equipped with a water filter and/or a descaling and/or softener system.

With 14 a dispensing arrangement is indicated, to which the coffee-based beverage is supplied from the brewing unit 12. The dispensing arrangement 14 may comprise, for example, a duct ending with a nozzle, to dispense the beverage in the cup C previously placed at the pick-up zone 4.

Reference 15 designates a control unit of the vending machine 1, comprising for example an electronic control board which manages in a known manner operation of various functional elements or units of the vending machine, also on the basis of commands or signals received from other elements of the machine, such as the user interface 3, the aforementioned volumetric meter of the supply arrangement 13, and at least one temperature sensor 16 which is arranged inside the cabinet 2 and which is also in signal communication with the unit 15; the function of this sensor will be described below.

In various preferential embodiments, inside the cabinet 2 is also at least a part of a cooling arrangement, configured to cool the coffee beans contained in the storage volume 10. In accordance with a characteristic of the invention, the cooling arrangement includes a refrigeration unit, indicated with 20 as a whole. In various preferential embodiments, the refrigeration unit 20 is arranged in the lower portion of the cabinet 2, in particular anchored at a base of the cabinet, for the reasons explained below.

Referring to figure 2 - wherein only the elements useful for the purpose of understanding the invention are shown - following the request by a user, set through the user interface 3, the grinder 11 grinds a certain amount of coffee beans - schematized by the arrows CB - coming from a lower outlet 40a of the storage volume 10, in order to supply a dose of ground coffee - schematized by the arrow GC - which is fed to the brewing unit 12, for example via a relative inlet 12a. To a second inlet 12b of the unit 12 a certain amount of hot water is fed, schematized by the arrow HW, via the supply arrangement 13 (in figure 2, reference 13a can be meant as the outlet of the boiler for water heating). The brewing unit 12 prepares the beverage through the interaction between the dose of ground coffee GC and the amount of hot water HW. The coffee -based beverage - schematized by the arrows EC - comes out of an outlet 12c of the unit 12 and, through the dispensing arrangement 14, is supplied outside the cabinet of the vending machine (in figure 2, reference 14a can be meant as the nozzle for dispensing the coffee-based beverage).

According to a characteristic of the invention, the storage volume 10 comprises an inner container, designated by 40, for receiving and storing the coffee beans CB. For example, the inner container 40 may consist of a hopper container, preferably but not necessarily of plastic material, having a lower outlet 40a, for example a protruding outlet having a substantially cylindrical shape. The container 40 can have a containment volume approximately ranging from 10 to 15 litres. The container 40 could also be a typical sachet of coffee beans, provided with a relatively rigid sleeve to define the outlet 40a, or a rigid jar provided with the outlet 40a.

Note that in the figures the outlet 40a of the container 40 and the grinder 11 are shown spatially separated from one another only for the sake of clarity of the representation. In the practical implementation, however, it is preferable that the outlet 40a of the container 40 is fitted or in any case coupled to a corresponding inlet of the grinder 11, that is with the two components 40 and 11 directly adjacent and attached to each other, to constitute a sort of single unit (although the two parts are preferably separable, in order to allow removal of the container 40).

According to a further characteristic of the invention, the cooling arrangement comprises an outer casing, indicated by 41, which surrounds at least partially the container 40, and between the container 40 and the outer casing 41 a gap is defined, indicated by 42, having at least one inlet 42a and at least one outlet 42b.

In various embodiments the outer casing 41 has a cross-sectional shape similar to that of the container 40, but larger in size, so as to surround the container 40 at least peripherally, preferably at a distance (without excluding possible areas of mutual contact). Preferably, the casing 41 also has a bottom wall, so that the gap 42 also extends in a position corresponding to the bottom of the container 40; for this purpose, the bottom of the casing 41 can be provided with a lower opening, to enable passage of the outlet 40a - if this is a protruding one - and in any case functional connection of the outlet 40a to the inlet mouth of the grinder 11.

Preferably, the outer casing 41 comprises a layer of (heat) insulating material 43, particularly on its outer side, in order to minimize possible heat exchange toward the outside and therefore maximize heat exchange toward the inside, i.e., to the coffee beans. In various embodiments, the outer casing 41 is provided with an opening/c losing element, such as an openable or removable door or lid, indicated with 41b. Element 41b is designed for enabling access to the container 40, for the purpose of replacement thereof, or filling thereof with coffee beans; preferably, the opening/c losing element 41b is also provided with a respective insulation, for the same reasons as indicated above. Note that, in the figures, the door or lid 41b is represented in the upper part of casing 41: however, in the practical implementation of the invention, it may be positioned differently, for example at a side of the casing 41.

In various embodiments, such as those exemplified, the container 40 is configured as a container closed above, that is, without aa upper loading mouth: in such embodiments, the container 41 can therefore be conceived as a disposable refill container (for example a sachet or a jar), or as a refillable container, exploiting the outlet 40a also for filling the container itself. By contrast, in other embodiments not represented, the container 40 is provided with a loading opening, not necessarily at the top, with an associated opening/ closing element, in order to allow the topping up of the coffee beans.

As already indicated, according to a preferential characteristic of the invention, inside the cabinet 2 a refrigeration unit 20 is mounted. Note that figure 2 has a schematic character, with the position of the components - such as the unit 20 - which is dictated by mere requirements of clarity of representation. For example, as already indicated, in embodiments currently considered as preferential ones, the unit 20 is housed in the lower part of cabinet 2, in particular on its base; the positioning of the unit 20 in the upper part of the cabinet 2 would in fact make it difficult the operations required for topping up or replace the container 40 of the storage volume 10, as well as of any storage volumes 10' of other products (in the practical implementation, the vending machine 1 is preferably also configured for the dispensing of beverages that are not obtained from coffee beans, such as beverages obtained from soluble precursors, such as tea, and/or packaged food products, such as brioches or snacks). The positioning of the unit 20 at the base also reduces generation of significant vibratory phenomena on the cabinet 2, when a compressor of the unit 20 operating.

In various embodiments, the refrigeration unit is of a design and operation known in itself, and may comprise, for example, a compressor 21, a condenser 22, an expansion valve 23 (or a device having similar function) and an evaporator 24. Preferably, the cold side of the unit, i.e., the evaporator 24, has a first electric fan 25 operatively associated thereto; a second electric fan 26 can be operatively associated to the hot side of the unit, i.e., the condenser 22, although this is not strictly necessary in some applications.

In various embodiments, the unit 20 has its own casing 27, within which the corresponding components are positioned, such as the components 21-26. In preferential embodiments, the casing 27 of the unit 20 defines an internal chamber that is divided - for example by means of an intermediate wall 27a - into two halfchambers, one housing the condenser 22 and the possible electric fan 36, and the other one housing the evaporator and its electric fan 25. The compressor 21 and the expansion valve 23 are preferably located in the half-chamber of the condenser 22.

In various embodiments, the casing 27 of the refrigeration unit 20 has relatively small dimensions, especially ranging from 350-550 mm (height) x 300- 400 mm (width) x 350-400 mm (depth). The small dimensions of the unit 20 advantageously allow its positioning inside the cabinet 2; however, a positioning of the same unit outside of the cabinet is not excluded from the scope of the invention, for example when it is desired to equip a pre-existing vending machine with a cooling arrangement in accordance with the invention (an example to this effect is given in Figure 8).

According to a characteristic of the invention, the refrigeration unit 20 has at least one first outlet for a flow of cooled air, connected via at least one first delivery duct to the inlet 42a of the gap 42, and at least one first inlet for a flow of air to be cooled, connected via at least one first return duct to the outlet 42b of the gap 42. Referring to figure 2, the aforementioned outlet and inlet of the unit 20, indicated with 28 and 29, respectively, are at the half-chamber housing the evaporator 24, in positions respectively downstream and upstream of the evaporator itself, having as reference the direction of the air circulation flow. As it can be seen, the outlet 28 is connected via a duct - schematized by the arrow AC - to the inlet 42a of the gap 42, while the outlet 42b of the gap 42 is connected via a duct - schematized by the arrow WA - to the inlet 29.

In this way it is possible to obtain a circulation of air that crosses the gap, in a substantially closed path. The cold created by the evaporator is transferred to the air, which through the outlet 28 and the duct AC reaches the inlet 42a of the gap 42. This cooled air passes through the gap 42, so cooling the inner container 40 and the contents thereof, and takes heat therefrom, and then leaves the gap 42 via the outlet 42b, to return to the evaporator 24 via the duct WA and the inlet 29.

In various preferential embodiments implementation, the circulation of the cooled air and of the air to be cooled is a forced circulation, obtainable thanks to the use of an electric fan, such as the fan indicated with 25. In the example, for this purpose, the outlet 28 and the inlet 29 of the unit 20 are in positions respectively downstream and upstream of the electric fan 25, with reference to the direction of the air circulation flow. The electric fan 25 is configured for at least forcing the cooled air into the duct AC, and preferably also to suck the air to be cooled from the duct WA.

Of course, the fluid dynamic characteristics of the air circuit will be chosen in order to ensure that the gap 42 is involved as a whole by the flow of cooled air coming from the duct AC; for example, the sizing (such as the passage section) of the inlets 29, 42a, the outlets 28, 42b, the gap 42 and the ducts AC, WA will be determined according to the characteristics of the unit 20, for example the flow rate of the electric fan 25.

In various preferential embodiments, the ducts AC and WA are (thermally) insulated ducts, in order to avoid heat losses (cold losses from the duct AC and heat losses from the duct WA).

The proposed mode of ventilated cooling for the containment volume 10, and in particular for the inner container 40, is very efficient from the energy viewpoint, and causes a low humidity, with an ensuing lower risk of condensation at the volume 10, which could contribute to the deterioration of the coffee beans. The fact that the cooled air produced by the unit 20 is not blown directly inside the container 40, or on the coffee beans, avoids damaging the aromatic quality of the product, depriving it of organoleptic peculiarities; direct blowing on the beans, moreover, could cause a deterioration of the product due to the humidity of the cooled air and the condensation that would be generated on the internal walls of the container 40, due to the temperature difference between inside and outside.

In various preferential embodiments, the at least one inlet 42a and the at least one outlet 42b of the gap 42 are in a lower region and in an upper region, respectively, of the outer casing 41, i.e., of the gap itself. With this solution, the coldest air coming from the duct AC (understood as air that has not yet performed a cooling function) firstly involves the lower area of the container 40 which, as mentioned, is in the immediate vicinity or in contact with the inlet of the grinder 11, in which grinding is usually carried out: in this way it is possible to obtain a cooling by conduction of this grinding area, as explained below.

The operation of the refrigeration unit 20 is preferably controlled by the control unit 15, at least as a function of a temperature that exists within the volume bounded by cabinet 2. This detection of the internal temperature is carried out via the sensor 16, preferably in an area subject to refrigeration by the unit 20: the detected temperature is compared with a pre-set threshold value, for example set when installing distributor 1, to operate the compressor 21 when necessary, and then carry out a typical refrigeration cycle. Preferably, for the purpose of controlling operation of the unit 20, there are also means, in themselves known, to control the temperature at the outlet of the evaporator 24 and to control the compressor 21 with an ON/OFF or PID logic, according to methods widely known in the refrigeration and environmental conditioning field. In various embodiments the aforementioned threshold temperature is greater than 0 ⁰ C, particularly comprised between +5 and + 25 °C, preferably between + 15 and + 20°C, depending on the desired level of preservation of the product; for example, a preferential threshold value is approximately +18°C, which is a temperature suitable for preventing rapid oxidation and/or rancidity of coffee beans and/or ground coffee.

Of course, it is possible to provide the unit 20 with its own control unit, instead of implementing the corresponding control logic on the control unit 15 of the vending machine 1, in which case the sensor 16 will be connected in signal communication with the control unit of the refrigeration unit 20.

In order to exemplify a possible operating cycle of the cooling system, let us assume that:

- the temperature outside the cabinet, on an average summer day in Italy, reaches the value of about 33-34°C;

- inside the cabinet, due to the presence of heating elements (such as the brewing unit 12 and the boiler of the supply arrangement 13), temperatures on average higher than the external one of about 6-7 ⁰ C are detected (therefore an average internal temperature of about 40 ⁰ C);

- the pre-set threshold temperature is equal to 18°C.

When, through the sensor 16, a temperature equal to or higher than the threshold temperature of 18°C is detected inside the cabinet 2, the unit 20 is activated for the production of cooled air. The evaporator 24 then cools the air which, through the electric fan 25 and the outlet 28, is forced into the duct AC, to reach the gap 42 by means of the outlet 42a. This cold air, indirectly coming into contact with warmer objects, represented by the container 40 and the beans contained thereinto, heats up as it rises into the gap 42, and then returns to the unit 20 (by means of the outlet 42b, the duct WA and the inlet 29), to be cooled again to the desired temperature, and then brought back inside the gap 42. Of course, like any physical system, the desired temperature for cooling the container 40 and its contents CB is reached only after passing an initial thermal transient.

In various embodiments, the at least one temperature sensor 16 is positioned inside the cabinet 2 in the region where the grinder 11 is located, in order to ensure that the unit 20 is activated and deactivated, for the purpose of cold generation, when the temperature in that region is equal to or greater than the pre-set threshold value.

The indicated positioning region of the sensor 16 is considered preferential because, for the purpose of implementing the invention, the grinder 11 can represent a critical point for the optimal preservation of coffee. The grinder 11 is in fact a component that, by its nature, tends to originate heat (both due to the operation of a corresponding electric motor, and due to the action carried out by its grinding blades). At the inlet mouth of the grinder 11 - in which, as mentioned, it is preferably directly coupled the outlet 40a of the container 40 - or in its immediate vicinity it is usually defined the grinding area. In this area there may remain a minimum amount of coffee beans and, above all, following a grinding phase, in this area there generally remains a minimum amount of ground coffee: it has been experimentally found that this residue of coffee powder - if exposed to unsuitable storage conditions - tends to deteriorate very quickly, with a sudden increase in its oxidative state.

For these reasons it is therefore preferable that the temperature measurement according to which the refrigeration unit 20 is controlled takes place in the area of the grinder 11. This obviously does not exclude that, in addition or alternatively, a temperature sensor can be placed in the region of the storage volume 10 (for example inside the gap 42, or in contact with the casing 41 - including its door or lid 41b - or in contact with the container 40), or at the delivery duct WA.

It should be considered that, in the solution according to the invention, the cooling of the coffee beans is obtained by pure conduction, that is, it is an "indirect" cooling, which avoids the flow of cold air directly on the coffee beans, for the reasons set out above, related for example to the loss of aromatic quality. As a matter of fact, the cooled air circulating in gap 42 cools the walls of the inner container 40, with part of the cold being transferred to the "peripheral" beans and air that are directly in contact with these walls; these "peripheral" grains and air in turn transfer part of the cold to the adjacent beans and air, and so on towards the centre of the container 40.

This cooling mode has the consequence that even any coffee beans remained at the inlet mouth of the grinder 11, and at least part of the grinder itself, are cooled by conduction or natural convention. However, this cooling may not be sufficient for cooling any ground coffee residue that remained in the grinding area of the grinder 11. For this reason, in particularly advantageous embodiments of the invention, the cooling arrangement of the vending machine 1 is configured to cool at least part of the grinder 11.

The at least partial cooling of the grinder 11 can be carried out in a direct and active manner. Possible embodiments of this type are shown in figures 3-7.

In the case of figure 3, the outer casing 42 also partially surrounds the grinder 11. For such a case, for example, an internal jacket 40' can be provided, that at least partially surrounds the grinder 11; this jacket 40' can be configured as a separate component or as a part protruding downward from the bottom of the container 40. The outer casing 41 is shaped to surround the 40' jacket, so that between them a respective part of the gap 42 extends. Also in such a solution the inlet 42a is preferably located in the lower part of the gap 42, here the part thereof that at least partially surrounds the grinder 11. As it can be seen, with such a type of solution, the cooled air introduced into the gap 42 allows to maintain at a controlled temperature even at least a part of the grinder 11, preferably a part that includes both the grinding area and the underlying dosage area, in which a residue of ground coffee may be present.

The jacket 40', although preferential, could be omitted, as in the example of figure 4, wherein the outer casing 41 is shaped to define a volume in fluid communication with the gap 42, in which the part of interest of the grinder 11 extends.

Of course, it is also possible to provide several inlets 42a for the cooled air, for example one at the grinder 11 and one at the lower area of the container 40 (for example in the position shown in figure 2), as well as several outlets 42b, for example one at the grinder 11 and one at the upper part of the container 40 (for example in the position shown in figure 2). Via corresponding ducts, preferably (thermally) insulated, the cooled air can be fed in series (in derivation) or in parallel to the inlets of the gap, and similarly the air to be cooled can be withdrawn in series or in parallel from the outlets of the gap.

In the case of figure 5, the cooling arrangement includes a second casing, designated by 50, which at least partially surrounds the grinder 11 and in which a respective gap 51 is defined, the latter having at least one respective inlet 51a and at least one respective outlet 51b. In embodiments of this type, the refrigeration unit 20 is configured to force cooled air also at the inlet 51a, and to receive air from the outlet 5 lb of the gap 51 to be cooled.

In the case of embodiments of the type shown in figure 5, the cooling arrangement comprises a second delivery duct, schematized by the arrow CA', and a second return duct, schematized by the arrow WA', connected to the inlet and the outlet of the gap 51, respectively. These additional ducts CA', WA' are also preferably (thermally) insulated ducts, for the reasons already explained.

In the example in figure 5 the delivery duct AC and the return duct WA' are formed by respective branches of the ducts AC and WA, such that the refrigeration unit 20 can be provided with a single outlet 28 and a single inlet 29, for the circulation of the cooled air and of the air to be cooled. By contrast, in the case of figure 6, the refrigeration unit 20 has a second outlet 28' for the cooled air, connected through the delivery duct AC to the inlet of the gap 51, and a single inlet 29 for the air to be cooled, with the ducts WA' and WA connected in series.

In this case, therefore, two flows of cooled air are supplied in parallel to the two gaps 42 and 51, while the flow of air to be cooled coming from the gap 51 is conveyed to the unit 20 together with the flow of air to be cooled coming from the gap 42. Obviously it is also possible to provide the unit with a second inlet 29', to which the duct WA' is directly connected, as schematized by hatching in figure 6, in order to fed in parallel the two flows of air to be cooled to the unit 20.

In general, therefore, as an alternative to a parallel connection between the outlets 28, 28' of the unit 20 and the inlets 42a, 51a of the gaps 42, 51, on the one hand, and between the inlets 29, 29' of the unit 20 and the outlets 42b, 5 lb of the gaps 42, 51, on the other hand, also "hybrid" circuit solutions are possible, that is, with:

- one of the delivery duct CA' and the return duct WA' which is formed by a respective branch of the delivery duct CA or the return duct WA, respectively, and

- the other of the delivery duct CA’ and the return duct WA' which is connected to a respective outlet 28' or a respective inlet 29', respectively.

In the variant embodiment of figure 7, the cooling arrangement of the vending machine 1 is designed to directly direct a flow of cooled air on at least one part of the grinder 11, i.e., without the mediation of a gap. In the case exemplified, the unit 20 has a second outlet 28' for cooled air that, via a duct schematized by the arrow CA", is blown directly on the grinder 11. A solution of this type can be useful, for example, besides to cool at least part of the grinder 11, also for reducing the overall temperature inside the cabinet 2.

Of course, in relation to the embodiments exemplified with reference to figures 3-7 the above indications apply, in relation to the prearrangement of the fluid dynamic characteristics of the air circuit.

It should also be noted that cabinet 2 is preferably provided with a ventilation inlet and a ventilation outlet, exemplified in 17 and 18 in figure 1, for example in the form of slits or gratings, for the disposal of the heat produced by the condenser 22 during operation of the refrigeration unit 20. As mentioned, preferably, the unit 20 can also comprise a second electric fan 26 associated with the condenser 22, for the suction - through the ventilation inlet 17 - of air from the environment outside the cabinet 2, for the cooling of the condenser 22, and for the expulsion into the environment outside the cabinet 2 - through the ventilation outlet 18 - of air that has been heated by the condenser 22.

In the examples shown, the casing 27 of the unit 20 has, particularly at the half-chamber housing the condenser 22, a respective inlet 30 and a respective outlet 31, in positions respectively downstream and upstream of the condenser 22, with reference to the direction of the air circulation flow. This inlet 30 and outlet 31 are connected in fluid communication with the inlet 17 and outlet 18 of the cabinet, respectively, for example directly or through (thermally) insulated ducts. In this way heat dissipation from the unit 20 to the inside of the cabinet 2 can be reduced.

The characteristics of the present invention are clear from the above description, as are its advantages. It is clear that numerous variants are possible for the person skilled in the art to the vending machine described as an example, without departing from the scope of the invention as defined by the claims that follow.

As mentioned, the unit 20 could be placed outside the cabinet 2: such a case is exemplified in figure 8. In the example, the ducts CA and WA extending from the outlet 28 and the inlet 29 of the unit 20 will pass through in corresponding openings 17', 18' (or in a single opening) defined in a wall of the cabinet 2). The inlet 30 and the outlet 31 of the casing of the unit 20 can instead open directly onto the external environment.

It will be appreciated that the refrigeration unit 20, or more generally the cooling arrangement, can possibly also be exploited for the conditioning of other parts of the vending machine 1 inside the cabinet 2, for example in ways similar to those exemplified in figures 2-7. Such an additional cooling may concern, for example, one or more volumes of containment of soluble substances (e.g., the volumes indicated with 10' in figure 1, preferably including containers similar to that indicated with 40), and/or a tank belonging to a drinking water dispenser (exemplified in 10" in figure 1), and/or the internal volume of the cabinet 2, and/or the same brewing unit 12 (although heated by the action of hot water during the dispensing of a beverage, in the unit 12 there may remain residues of ground coffee, for which a cooling can be advantageous for the same reasons as highlighted above in relation to the residues that may remain in the grinder 11). As previously indicated, the problems underlying the invention can also occur in relation to beverage precursors other than coffee beans, such as precursors already in granular or powder form. The concepts of the invention are therefore also applicable for the cooling of one or more storage volumes for said different precursors that may are possibly arranged inside the vending machine cabinet, such as those schematically indicated with 10' in figure 1. In possible embodiments, in one and the same outer casing of the type previously indicated with 41 there could be housed a plurality of containers of the type previously indicated with 40, so as to define a single gap having functions of the gap indicated with 42, which surrounds at least in part each of said containers.