Milk module for producing milk-based beverages

Abstract

A milk module (3) for producing milk-based beverages, integrable in a machine (1) for producing milk-based beverages; the milk module (3) comprises a milk pump (10); a milk suction line (9) extending from a milk inlet to a suction side of the supply pump (10); a milk delivery line (15) extending from a delivery side of the milk pump (10) to a dispensing nozzle (16); and an air line (12) to allow a controlled given amount of air to flow into the milk suction line (9) at an air emanation point (13); wherein the milk module (3) further comprises a three-way diverter valve (33) arranged on the milk suction line (9), fluidically connected to the air line (12) by means of a connecting duct (34), and electronically controllable to allow water, optionally with detergent, sucked by the milk pump (10) into the milk suction line (9) during the washing mode, to selectively enter the connecting duct (34) to flow along the air line (12) and return to the milk suction line (9) at said air emanation point (13).

Description

[0001] MILK MODULE FOR PRODUCING MILK-BASED BEVERAGES

[0002] Cross-Reference to Related Applications

[0003] This application claims priority to European patent application No. 24180599.3 filed on 06.06.2024 and Italian patent application 102025000013075 filed on 05.06.2025, the content of which is incorporated herein by reference.

[0004] Technical Field of the Invention

[0005] The invention relates to a milk module for producing hot or cold, foamed or non-foamed milk, and integrable in a machine for producing milk-based beverages. In particular, the invention finds advantageous application in table-top machines for producing milk-based beverages, to which reference will be Made in the description without loosing in generality.

[0006] State of the Art

[0007] As is known, in the above-mentioned beverage production machines, the milk module usually comprises a washing circuit designed to periodically clean all those components of the milk module that, in use, come into contact with milk and, for this reason, are likely to be subjected to the proliferation of bacteria. Usually, the milk module is subjected to a water rinsing process at the end of each milk-based beverage producing cycle and a more in-depth washing process with water and detergent when the beverage production machine is not operating, normally at the end of a work day.

[0008] A known milk module usually comprises a milk line provided with a pump for sucking fresh milk from a milk container, a foaming device, a heating device and a dispensing nozzle, through which hot or cold, foamed or non-foamed milk is delivered into a cup or similar container; and an air line, through which the milk line can be supplied with a certain amount of air for producing foamed milk.

[0009] In order to carry out the above-mentioned rinsing and washing processes, the known milk modules also comprise a washing line through which the milk line can be supplied with a given amount of water, or water and detergent, which, after flowing through the conduits and components of the milk line, is drained into a waste water collection container.

[0010] Examples of milk modules of the above described type are known from WO 2022 / 123516 and WO 2022 / 123520 to the Applicant. Sometimes, the washing line is also configured to allow at least part of the air line to be washed, in particular the portion of the air line that opens into the milk line and is particularly exposed to contamination.

[0011] Examples of milk modules with a washing line configured to also wash part of the air line are known from EP 1561407 Bl, EP 3 610 762 Bl, EP 2 353 472 Bl, EP 4 108 143 Al, EP 3426109 Bl, EP 2 299 881 Bl.

[0012] Object and Summary of the Invention

[0013] The object of the present invention is to improve the milk modules described in WO 2022 / 123516 and WO 2022 / 123520 to enable at least part of the air line to be washed.

[0014] According to the present invention, a milk module for producing milk-based beverages and a beverage producing machine featuring said milk module are provided, as claimed in the appended claims.

[0015] Brief Description of the Drawings

[0016] Figure 1 shows a hydraulic circuit of a machine for producing milk-based beverages featuring milk module according to a preferred embodiment of the present invention.

[0017] Figure 2 shows a hydraulic circuit of the machine of Figure 1 featuring a milk module according to a further embodiment of the present invention.

[0018] Description of Preferred Embodiments of the Invention

[0019] The invention will now be described in detail with reference to the attached figure to enable a skilled person to realize and use it. Various modifications to the embodiments presented shall be immediately clear to persons skilled in the art and the general principles disclosed herein could be applied to other embodiments and applications but without thereby departing from the scope of protection of the present invention as defined in the appended claims. Therefore, the present invention should not be considered limited to the embodiments described and shown but should be granted the widest protective scope in accordance with the features described and claimed.

[0020] Where not otherwise defined, all the technical and scientific terms used herein have the same meaning commonly used by persons of ordinary skill in the field pertaining to the present invention. In the event of a conflict, this description, including the definitions provided, shall be binding. Furthermore, the examples are provided for illustrative purposes only and as such should not be considered limiting. In order to facilitate understanding of the embodiments described herein, reference will be made to some specific embodiments and a specific language will be used to describe them. The terminology used herein is for the purpose of describing only particular embodiments and is not intended to limit the scope of the present invention.

[0021] Figure 1 schematically shows a machine 1 for producing milk-based beverages and comprising a brewing unit 2 to produce beverages such as espresso and beverages from soluble products, and a milk module 3 to produce of hot or cold, foamed or non-foamed milk.

[0022] The brewing unit 2 comprises a plurality of conventional functional assemblies and, for this reason, will not be described in detail. In general, the brewing unit 2 comprises a brewer (not shown) to produce espresso, one or more mixers (not shown) to produce beverages from soluble products, a heater 4 to produce hot water or steam, and a pump (not shown) to supply the brewer and the mixers with hot water required to produce beverages.

[0023] The machine 1 further comprises a beverage dispensing compartment 5, where a group of dispensing nozzles 6 are arranged, which are fluidically connected to the brewing unit 2 via respective supply lines 7 to receive, in use, beverages produced by the brewing unit 2 and dispense them into a cup or similar container (not shown) on a cup-carrier grid in the beverage dispensing compartment 5.

[0024] The milk module 3 is selectively fluidically connectable to the brewing unit 2, more precisely to the heater 4, to receive, during operation, steam and hot water to be used, as explained more in detail below, to heat the milk and, respectively, to wash those components of the milk module 3 that, in use, come into contact with the milk and, hence, that need a regular cleaning in order to avoid the proliferation of bacteria.

[0025] Figure 1 schematically shows a hydraulic circuit of the milk module 3, comprising:

[0026] - a milk container 8, which is preferably arranged inside a refrigerated area to keep the milk at a temperature ranging from 3° to 5°;

[0027] - a suction line 9 extending from the milk container 8 to a suction side of a pump 10, preferably a gear pump, and comprising a shut-off valve 11 arranged at an end of the suction line 9 immersed in the milk container 8 and operable to open and close the fluid communication between the milk container 8 and the suction line 9;

[0028] - an air line 12, through which an ambient air flow can be introduced into the suction 9 at a T-joint 13 arranged upstream of the pump 10. The inflow of air into the air line 12 is controlled by a valve 14, which enables or inhibits the introduction of an air flow into the air line 12 depending on whether foamed or non-foamed milk, respectively, has to be produced. Conveniently, the valve 14 is a proportional solenoid valve, which allows the air flow rate to be adjusted according to closed-loop or open-loop control algorithms, which are widely known in the sector; and

[0029] - a delivery line 15 designed to convey milk or milk and air mixture from the pump 10 to a milk dispensing nozzle 16 which is arranged in the beverage dispensing compartment 5 and is part of the group of dispensing nozzles 6.

[0030] The delivery line 15 has, downstream of the pump 10, a flow restriction 17 which defines a concentrated reduction of the cross section of the delivery line 15 so as to causa, in use, the milk and air mixture flowing therethrough to be subjected to a quick compression and to a successive quick expansion, which transforms, based on a principle well known to a person skilled in the art, the milk and air mixture into foamed milk.

[0031] The flow restriction 17 can be in the form of a non-adjustable nozzle or a baffle or a throttle valve, which can be either adjustable or non-adjustable.

[0032] The delivery line 15 comprises a first single-duct section on which the flow restriction 17 is arranged and formed by a single duct, and a second double-duct section, which is connected to the first single-duct section by a bifurcation 18 and comprises two parallel ducts, both opening into the milk dispensing nozzle 16. One of the two conduits, hereinafter referenced by 15A, supplies foamed or non-foamed hot milk to the milk dispensing nozzle 16, whereas the other duct, hereinafter referenced by 15B, supplies foamed or non-foamed cold milk to the milk dispensing nozzle 16.

[0033] The milk or the foamed milk flowing in the duct 15A is heated by a heater 19, which, according to a preferred embodiment shown in Figure 1, is in the form of a heat exchanger, in which the milk or the foamed milk is indirectly heated by a steam flow while flowing along a spiral-shaped portion of the duct 15A.

[0034] The steam flow supplied to the heater 19 is produced by the heater 4 of the brewing unit 2 and is conveyed to the heater 19 by a steam line 20 with a first end fluidically connected, via a three-way valve 22, to a hot water / steam supply duct 21, which, in turn, is directly or indirectly connected to an outlet of the heater 4, and with a second end fluidically connected to an inlet of the heater 19 to supply the latter with the steam flow.

[0035] The condensation water that is formed, during operation, by the cooling of the steam in the heater 19 is conveyed into a discharge line 23 extending from the heater 19 to a waste container 24

[0036] Preferably, no shut-off valves are provided along the duct 15A and, hence, the delivery line 15 is always in fluid communication with the milk dispensing nozzle 16, regardless of whether steam is supplied to the heater 19 or not.

[0037] Along the duct 15B a shut-off valve 25 is instead provided, which can be operated so as to allow the foamed or non-foamed cold milk to flow or prevent it from flowing into the duct 15B depending on the type of beverage to be produced, as described more in detail below.

[0038] The milk module 3 further comprises a washing circuit having the function of washing the ducts of the milk module 3 where milk flows, both by a mere rinsing with water at the end of each milk-based beverage producing cycle or after the milk module 3 has not been used for a given amount of time, and by a more in-depth washing with detergent, which is normally carried out when the machine 1 is turned off, for example at the end of the day.

[0039] The washing circuit comprises a water supply line 26 to supply the suction line 9 with a hot water flow from the heater 4.

[0040] For this purpose, the water supply line 26 has an inlet coupled to an outlet of the three-way valve 22 to selectively fluidically communicate with the hot water / steam supply duct 21 and receive hot water from the heater 4. The water supply line 26 opens into the suction line 9 at a T-joint 27 between the shut-off valve 11 and the T-joint 13, where the air line 12 open into the suction line 9.

[0041] The washing circuit further comprises a drainage line 28 having the function of diverting into the waste container 24 the rinsing water, or water and detergent mixture, reaching the outlets of the ducts 15A and 15B, so as to prevent it from reaching the outlet of the milk dispensing nozzle 16.

[0042] Conveniently, the drainage line 28 is enabled during rinsing and washing operations to suck hot water or water and detergent mixture flowing along the suction line 9 and the delivery line 15 and, at the beginning of each milk-based beverage producing cycle, to suck the water that, after each rinsing, remains along the suction line 9 and the delivery line 15.

[0043] According to a preferred embodiment shown in Figure 1, the drainage line 28 has a first end fluidically connected to the milk dispensing nozzle 16 upstream of the outlet thereof and a second end immersed into the waste container 24, and comprises a pump 29 and a shut-off valve 30, which is arranged on the suction side of the pump 29 and has the function of causing, when it is closed, the milk dispensing nozzle 16 to be fluidically isolated from the waste container 24.

[0044] Optionally, the shut-off valve 30 can be omitted if the pump 29 is so designed so as to cause, when it is turned off, a fluid-tight separation between its suction and delivery sides.

[0045] The washing circuit is also configured to allow the air line 12 to be cleaned during the washing and rinsing phases of the hydraulic circuit.

[0046] In particular, the washing circuit includes a diverter valve 33, which is arranged along the suction line 9 and is fluidically connected to the air line 12 via a connecting duct 34, preferably at a point close to the air inlet valve 14 and upstream of a non-return valve 35.

[0047] The diverter valve 33 is a three-way solenoid valve controlled by an electronic control unit 32 of the machine 1 so that, during the washing cycles and at predetermined intervals, the washing liquid sucked by the pump 10 into the suction line 9 is diverted from the suction line 9 into the connecting duct 34 so as to flow into the air line 12 and then re-enter the suction line 9 at the T- joint 13. In this way, the air line 12 can be washed by any milk that may have flowed into the air line 12 during the preparation of a beverage.

[0048] As shown in Figure 1, the diverter valve 33 has an inlet and a first outlet in fluidic communication with respective sections of the suction line 9, and a second outlet in fluidic communication with the connecting duct 34.

[0049] The diverter valve 33 is electronically controllable to assume a first configuration, in which the diverter valve 33 puts the two sections of the suction line 9 in direct fluidic communication so as to form a fluid continuity in the suction line 9, and fluidically separates the connecting duct 34 from the suction line 9, and a second configuration, in which the diverter valve 33 puts the suction line 9 and the connecting duct 34 in direct fluidic communication, while interrupting the direct fluidic communication between the two sections of the suction line 9.

[0050] Conveniently, as illustrated in the preferred embodiment of Figure 1, the diverter valve 33 is arranged along the section of the suction line 9 upstream of the T-joint 27. According to the embodiment shown in Figure 2, the diverter valve 33 may be arranged on the section of the suction line 9 downstream of the T-joint 27.

[0051] The operation of the milk module 3 will be described below with reference to three different operating steps:

[0052] 1) production of hot or cold, foamed or non-foamed milk;

[0053] 2) rinsing with water at the end of a milk-based beverage producing cycle;

[0054] 3) the washing with detergent when the machine is not working.

[0055] 1) Production of hot or cold foamed or non-foamed milk

[0056] In response to a selection of a milk-based beverage, the electronic control unit 32 of the machine 1 operates the pump 10 to cause a given amount of milk to be sucked out of the milk container 8 and supplied to the delivery line 15. If foamed milk is required, the electronic control unit 32 opens the valve 14 to allow a given amount of air to flow into the air line 12 and be sucked into the milk flowing along the suction line 9. The pump 10 is then operated to cause the milk and air mixture to flow through the flow restriction 17 in order to be transformed, in a cold state, into foamed milk.

[0057] If foamed or non-foamed hot milk is required, the electronic control unit 32 closes the shutoff valve 25 along the duct 15B to prevent milk from flowing therealong and operates the heater 4 of the brewing unit 2 to cause steam to be produced and supplied to the hot water / steam supply duct 21. At the same time, the three-way valve 22 is controlled so as to cause the steam produced by the heater 4 to be supplied to the heater 19 to heat the foamed or non-foamed milk flowing along the duct 15B.

[0058] If foamed or non-foamed cold milk is required, the shut-off valve 25 of the duct 15B is opened in order to allow milk to flow therethrough, whereas the three-way valve 22 is controlled to prevent steam from being supplied to the heater 19. In this way, foamed or non-foamed cold milk reaches the milk dispensing nozzle 16 flowing through both ducts 15A and 15B.

[0059] 2) Rinsing with water at the end of preparation of a beverage

[0060] At the end of a milk-based beverage producing cycle, the milk module 3 is subjected to a short rinsing with hot or cold water in order to eliminate milk residues present along the suction line 9 and the delivery line 15 and in the different operating components distributed therealong.

[0061] During this rinsing phase, the electronic control unit 32 closes the shut-off valve 11 to fluidically isolate the milk container 8, opens the shut-off valve 25 to allow water to enter the duct 15B, and closes the valve 14 at the inlet of the air line 12.

[0062] At the same time, the three-way valve 22 is controlled so as to cause water to flow into the water supply line 26, and the pump 10 is operated to cause water to flow, through the pump 10, along the suction line 9 and the delivery line 15 and, through both ducts 15A and 15B, reach the milk dispensing nozzle 16.

[0063] Operation of the pump 29 prevents water, once it has entered the milk dispensing nozzle 16, from reaching the outlet of the dispensing nozzle 16. As a matter of fact, water is sucked by the pump 29 immediately upstream of the outlet of the dispensing nozzle 16 and is conveyed, through the drainage line 28, into the waste container 24. The shut-off valve 30 is open during this step.

[0064] As a result of the suction generated by the pump 29, drainage of the water flowing out of the ducts 15A and 15B is substantially total, which means that not even a part of water reaches the outlet of the milk dispensing nozzle 16. This is possible thanks to the suction force generated by the pump 29 and to the fact that the milk dispensing nozzle 16 is designed so that the inlet of the drainage line 28 is, for the water coming from the ducts 15A and 15B, a preferred path compared to the outlet of the milk dispensing nozzle 16. At the end of the rinsing, the suction line 9 and the delivery line 15 remain full of water, which is sucked at the beginning of the following milk production cycle by operating the pump 29 for a predetermined amount of time, which is calculated based on the water volume to be sucked. Preferably, at the beginning of a new milk producing cycle, the pump 29 is operated at least for an amount of time enough to suck the water contained in the part of circuit upstream of the milk dispensing nozzle 16.

[0065] Preferably, the above-described rinsing is carried out, as mentioned before, after each milkbased beverage producing cycle and / or after a predetermined amount of time during which the milk module 3 is inoperative.

[0066] In the embodiment in which the diverter valve 33 is arranged on the section of the suction line 9 downstream of the T-joint 27, it is also possible to rinse the air line 12 with water. To this end, the electronic control unit 32 controls the diverter valve 33 so that, in one or more predefined time intervals, the water is diverted from the suction line 9 to the connecting pipe 34 so that it flows along the air line 12 and re-enters the suction line 9 at the T-joint 13.

[0067] 3) Washing with detergent

[0068] As already mentioned above, this in-depth washing is periodically carried out when the machine 1 is inoperative, typically at the end of a work day.

[0069] This in-depth washing comprises the three sub-steps described below: i. the milk container 8 is replaced with another container (not shown) containing a detergent, preferably in the form of a tablet or of a concentrated liquid.

[0070] During this first sub-step, the shut-off valve 11 between the container with the detergent and the T-joint 27 is open, the diverter valve 33 is set to allow the water to flow into the container and close the inlet to the air line 12, and the pump 10 is inoperative.

[0071] The three-way valve 22 is controlled to allow hot water to flow from the water / steam supply duct 21 to the water supply line 26 so as to reach, through the suction line 9, and fill the container containing the detergent, thus forming a water and detergent mixture. ii. Once the container has been filled with hot water, the supply of hot water is interrupted and the pump 10 is operated to extract the water and detergent mixture from the container and cause it to flow along the suction line 9 and along both ducts 15A and 15B of the delivery line 15. Simultaneously with the pump 10, also the pump 29 is operated to suck the washing mixture and convey it, through the drainage line 28, to the waste container 24. According to one embodiment, sub-step ii of washing with detergent may be preceded by an initial sub- step of pre-washing with clean cold water supplied to suction line 9 from water supply line 26 iii. Once the container is empty, at least one rinsing with clean water is carried out. To this aim, the above-described sub-steps i and ii are sequentially repeated, with the sole difference that no detergent is added to the container. Sub-steps i and ii are repeated, if necessary, until no more traces of detergent are detected in the rinsing water. To this aim, a conductivity sensor 31 may be used, which is preferably arranged close to the inlet of the suction line 9.

[0072] Preferably, at least two rinses should be carried out with clean water at a temperature of approximately 82°- 85°.

[0073] Conveniently, both washing with detergent and rinsing with hot water are not carried out continuously, but intermittently so as to maximise the cleaning effectiveness of the detergent and / or hot water on milk deposits during dwell intervals.

[0074] Furthermore, in the cleaning intervals, both during washing with detergent and rinsing with hot water, the diverter valve 33 is activated for predetermined time intervals so that the water containing detergent and, respectively, the clean rinse water flows through the air line 12 and cleans it.

[0075] At the end of the rinsing, the inlet of the suction line 9 is placed again in the milk container 8 and the milk module 3 is ready for a new production cycle.

[0076] Conveniently, both during the washing with detergent and the rinsing with water, the pump 29 is stopped for a few instants and then operated again, so that, in the instants in which it is inoperative, a small amount of water flows through the outlet of the milk dispensing nozzle 16 to remove milk residues possibly present between the inlet of the drainage line 28 and the outlet of the milk dispensing nozzle 16.

Claims

CLAIMS1. A milk module (3) for producing milk-based beverages, integrable in a milk-based beverage production machine (1); the milk module (3) comprises: a milk pump (10); a milk line comprising a milk suction line (9) extending from an inlet of the milk suction line (9) to a suction side of the milk pump (10), and a milk delivery line (15) extending from a delivery side of the milk pump (10) to a milk dispensing nozzle (16); and an air line (12) to controllably supply air into the suction line (9) at an air emanation point (13); wherein the inlet of the milk suction line (9) is supplied with milk in a milk-based beverage production mode, and with water, optionally with detergent, in a washing mode; characterised in that the milk module (3) further comprises a diverter valve device (33) arranged along the milk suction line (9), connected to the air line (12) by means of a connecting duct (34), and electronically controllable to allow water, optionally with detergent, pumped by the milk pump (10) into the milk suction line (9) during the washing mode, to selectively enter the connecting duct (34) to flow along the air line (12) and return to the milk suction line (9) at the air emanation point (13).

2. The milk module (3) of claim 1, further comprising: a first valve device (11) arranged between the inlet of the milk suction line (9) and the milk pump (10); a water supply line (26) opening into the milk suction line (9) at a water emanation point (27) between the first valve device (11) and the milk pump (10); and a second valve device (22) electronically controllable to cause the water supply line (26) to be selectively supplied with water; wherein, in the washing mode, the inlet of the milk suction line (9) is immersed in a washing container, optionally containing detergent, and the first valve device (11) and the second valve device (22) are electronically controlled to allow water to flow into the water supply line (26) and the suction line (9) so as to reach, through the first valve device (11), the inlet of the suction line (9) and fill the washing container; the milk pump (10) is electronically controlled to suck water, optionally with detergent, from the washing container and supply it, intermittently and for predefined time periods, along the milk suction line (9) and the milk delivery line (15) up to the milk dispensing nozzle (16).

3. The milk module (3) of claim 2, in which the diverter valve device (33) is electronically controlled during said washing mode to allow the water sucked from the washing container, optionally mixed with detergent, to flow into the air line (12), in one or more predefined time intervals, when the milk pump (10) is active.

4. Milk module (3) according to claim 2 or 3, wherein the diverter valve device (33) is arranged upstream of the water emanation point (27).

5. Milk module (3) according to claim 2 or 3, wherein the diverter valve device (33) is arranged between the water emanation point (27) and the air emanation point (13).

6. Milk module (3) according to anyone of claims 2 to 5, wherein the first valve device (11), the second valve devices (22) and the milk pump (10) are electronically controlled to operate the milk module (3) in a water-only rinsing mode , preferably carried out between two beverage production cycles or after a certain period of time, and in which the second valve device (22) is set to cause water to flow into the water supply line (26) and the milk suction line (9); the first valve device (11) is set to prevent water from reaching the inlet of the milk suction line (9), and the milk pump (10) is operated to supply water along the milk suction line (9) and the milk delivery line (15) to the milk dispensing nozzle (16).

7. A milk-based beverage production machine (1) comprising a milk module (3) according to anyone of claims 1 to 6.

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