Classifications

• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
  • A47J31/00—Apparatus for making beverages
  • A47J31/44—Parts or details or accessories of beverage-making apparatus
  • A47J31/4485—Nozzles dispensing heated and foamed milk, i.e. milk is sucked from a milk container, heated and foamed inside the device, and subsequently dispensed from the nozzle
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
  • A47J31/00—Apparatus for making beverages
  • A47J31/44—Parts or details or accessories of beverage-making apparatus
  • A47J31/46—Dispensing spouts, pumps, drain valves or like liquid transporting devices
  • A47J31/461—Valves, e.g. drain valves

Definitions

• the present invention relates to a milk module for preparing beverages, in particular hot or cold, frothed or non-frothed milk, from liquid milk of animal or plant origin.
• This type of milk modules are used as stand-alone units or, more commonly, are used alongside, or integrated in, machines for preparing coffee-based beverages to form therewith a multi-product preparation unit.
• a milk module of the type specified above normally comprises a milk line, which extends from a liquid milk container to a beverage dispensing nozzle and comprises: a milk pump to suck the milk from the container, an air inlet to allow air to be introduced in the milk line on the suction side of the pump, an frothing device arranged downstream of the milk pump, and a heating device arranged normally between the frothing device and the beverage dispensing nozzle.
• a given amount of air is introduced into the milk flow sucked from the container, and the resulting milk-air mixture is supplied under pressure to the frothing device to be frothed and then, if necessary, heated by the heating device.
• the frothing device comprises a flow restriction, for example formed by a fixed nozzle or by a fixed or adjustable throttle valve.
• the heating device normally comprises a through-flow heater, which may be an electric heater or a heat exchanger.
• the milk or milk-air mixture is heated by injecting a steam flow into the milk line.
• the amount of air introduced into the milk line represents an indispensable parameter for preparing frothed beverages having in the cups high requirements from both an organoleptic and an aesthetic point of view.
• recent decades have seen an evolution of the traditional systems based on an ON/OFF air control, wherein the air inlet is opened or closed by means of a solenoid valve with a fixed flow rate, depending on whether a frothed beverage is to be obtained or not, toward more sophisticated systems capable of proportionally controlling introduction of air in the milk line so that variable amounts of air can be supplied according to the beverage to be prepared.
• One of the most commonly used systems for proportionally controlling the amount of air consists in sucking air from the external environment by means of the action of the milk pump and, before introducing the sucked air into the milk line, electronically adjusting the air flow rate by means of a proportional solenoid valve.
• the solenoid valve is controlled by an electronic control unit of the milk module according to closed-loop or openloop control algorithms widely known in the field, based on various operating parameters, such as the type of milk, the temperature of the cold milk or of the milk-air mixture, the milk pump speed, etc.
• EP 3 181 021 Al (Steiner Weggis), in which the amount of air is adjusted by means of a proportional solenoid valve to obtain a given consistency of the milk foam.
• the proportional air solenoid valve is controlled by an electronic control unit based on the measurement of some operating parameters, such as the type of milk, the temperature of the milk in the milk container, and the temperature of the hot milk-air mixture.
• EP 3039999 Bl and EP 3040000 Al (Cimbali), in which the amount of air is adjusted by a proportional solenoid valve controlled by an electronic control unit according to a predetermined program stored in the electronic control unit.
• EP 3 426 110 Bl Douwe Egberts
• the amount of air is adjusted by a proportional solenoid valve controlled by an electronic control unit based on the temperature measured by a sensor arranged adjacent to or at the milk inlet.
• WO 2017155403 Al Douwe Egberts, in which the amount of air is adjusted by a solenoid valve controlled by an electronic control unit according to the type of beverage to be produced.
• the aim of the present invention is to provide a milk module for preparing beverages, in particular frothed or non-frothed milk, which allows the amount of air fed to the milk line to be accurately adjusted so as to improve the organoleptic and aesthetic qualities of the beverage with respect to the prior art systems.
• a milk module for preparing beverages, in particular frothed or non-frothed milk is provided, as claimed in the appended claims.
• the attached Figure shows a hydraulic diagram of a preferred embodiment of a milk module of the present invention.
• reference numeral 1 references, as a whole, a milk module 1 for producing hot or cold, frothed or non-frothed milk-based beverages, starting from liquid milk of animal or plant origin.
• the milk module 1 can be configured to operate as standalone milk module or can be connected to one or more automatic beverage preparation machines, for example coffee machines, to form an integrated multi-product production unit.
• automatic beverage preparation machines for example coffee machines
• the milk module 1 comprises a milk line 3 extending from a milk container 4, preferably housed in a cooler (not shown) designed to keep the milk at a temperature between 3°G and 5°C, up to a milk dispensing nozzle 5 arranged in a cup filling compartment (not shown).
• the milk line 3 comprises, in succession, a milk pump 6 to suck milk from the milk container 4, a flow restriction 7 arranged on a delivery side of the milk pump 6, and a milk through-flow heater 8.
• the flow restriction 7 could be arranged downstream of the milk heater 8.
• the milk pump 6 is a rotary displacement pump, preferably a gear pump.
• the flow restriction 7 may be formed by a fixed nozzle or by a fixed or adjustable baffle or throttle valve.
• the milk heater 8 is an electric heater, preferably an electromagnetic induction heater.
• the milk heater 8 could be a heat exchanger or a steam heater to inject a steam jet directly into the milk flow or indirectly by heating a milk duct.
• the milk module 1 further comprises an air line 9 extending from an air source, typically an external environment, through an air filter 10 and opening into the milk line 3 in a point thereof on the suction side of the milk pump 6, so that, in use, operation of the milk pump 6 causes, in addition to the suction of the milk from the milk container 4, also the suction of an air flow into the milk line 3.
• an air source typically an external environment
• an air filter 10 opening into the milk line 3 in a point thereof on the suction side of the milk pump 6, so that, in use, operation of the milk pump 6 causes, in addition to the suction of the milk from the milk container 4, also the suction of an air flow into the milk line 3.
• the air line 9 could open into a point of the milk line 3 on the delivery side of the milk pump 6, upstream of the flow restriction 7, and supplied by an air compressor.
• the flow restriction 7 defines a localized narrowing of the cross-section of the milk line 3 downstream of the milk pump 6 such that, in use, the milk-air mixture flowing therethrough undergoes a rapid compression and a subsequent rapid expansion that transforms, according to a principle well known to those skilled in the art, the milk-air mixture into frothed milk.
• the milk module 1 further comprises a three-way solenoid valve 11 at an inlet of the milk line 3 to selectively put the milk line 3 in fluidic communication with the milk container 4, in a normal beverage preparation configuration, and with a water line 12 in a washing configuration.
• the milk module 1 further comprises a further three-way diverter solenoid valve 13 downstream of the through-flow heater 8 to selectively put the milk line 3 in fluidic communication with the milk dispensing nozzle 5 in the beverage preparation configuration and with a wastewater container 14 via a discharge duct 15 in the washing configuration.
• the milk module 1 further comprises:
• an electronic control unit 18 in communication with, in particular electrically connected to, the pressure sensor 17 to receive the electrical output thereof and the proportional air solenoid valve 16 to supply electrical commands thereto, and programmed to control operation of the proportional air solenoid valve 16 based on the pressure of the milk-air mixture measured by the pressure sensor 17, to cause the milk module 1 to produce milkbased beverages having high quality both organoleptically and aesthetically, namely, that contain the correct amount of milk and that a top layer of milk foam has an appropriate height and consistency.
• the pressure sensor 17 could be arranged downstream of the flow restriction 7 or downstream of the milk heater 8.
• the electronic control unit 18 is programmed to:
• the target pressure profile P is constant over time to cause the proportional air solenoid valve 16 to be controlled so as to maintain a constant pressure of the milk-air mixture in the milk line 3, downstream of the milk pump 6.
• the pressure profile P has a time-varying development to cause the proportional air solenoid valve 16 to be controlled so that the pressure of the milkair mixture in the milk line 3, downstream of the milk pump 6, has a time development similar to that of the target pressure profile P.
• a target pressure profile P with a time-varying development could have a trend according to a broken line, formed by a plurality of substantially straight segments comprising a first segment with a first duration, in which the target pressure increases from an initial value, for example 1 bar, to a final value, for example 4 bar, in a given time interval; a second segment with a second duration, in which the target pressure remains substantially constant for a given time interval; and a third segment with a third duration, in which the target pressure returns to the initial value in a given time interval.
• the electronic control unit 18 is programmed to store data representative of different target pressure profiles P, each of which can be conveniently associated with a respective milk-based beverage that can be produced by the milk module 1 and that can be selected by a user through a graphical user interface (GUI) displayed on a display of an automatic beverage preparation machine with which the milk module 1 is associated or in which it is integrated.
• GUI graphical user interface
• the electronic control unit 18 is programmed to output electrical commands for the proportional air solenoid valve 16 by implementing, for example, a Proportional-Derivative (PD) controller.
• PD Proportional-Derivative
• controllers other than the one indicated, and which those skilled in the art may deem to be suitable for the purpose, can be implemented.
• the electronic control unit 18 is programmed:
• the electronic control unit 18 is programmed to sample the electrical output of the pressure sensor 17 at a given sampling frequency, e.g., every second, and compare the samples of the electrical output of the pressure sensor 17 with corresponding stored values of the target pressure profile P. After each adjustment intervention of the proportional air solenoid valve 16, the electronic control unit 18 is programmed to wait for a pressure transition interval before checking whether a further adjustment intervention of the proportional air solenoid valve 16 is to be performed.
• the present invention allows a pressure profile of the milk-air mixture downstream of the milk pump 6 to be to defined and set, which is reproduced throughout the dispensing of the beverage and that enables the milk module 1 to produce milk-based beverages that have a high quality both organoleptically and aesthetically, namely, that contain the correct amount of milk and that the top layer of milk foam has an appropriate height and consistency.
• the present invention allows the absence of milk in the milk line 3 downstream of the milk pump 6 to be identified and signaled, thus indicating that the milk container 4 is empty.
• the present invention allows any abnormalities in the milk module to be diagnosed and signaled, for example a failure of the milk pump.
• air could be introduced into the air line 9 by a compressed air source, for example an air compressor, electronically controlled by the electronic control unit 18.
• a compressed air source for example an air compressor
• the proportional air solenoid valve 16 could be omitted and the amount of air introduced into the milk line 9 could be adjusted by means of the appropriate control of the compressed air source, in the example considered the speed of the air compressor.
• the proportional air solenoid valve 16 could be maintained and arranged downstream of the compressed air source to finely adjust the amount of air introduced into the milk line 3.
• a heater could be arranged along the air line 9 to appropriately heat the air introduced into the milk line 3.

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• Engineering & Computer Science (AREA)
• Food Science & Technology (AREA)
• Apparatus For Making Beverages (AREA)

Priority Applications (5)

Applications Claiming Priority (4)

Publications (1)

Family

ID=84389089

Family Applications (1)

Country Status (5)

Cited By (1)

Citations (4)

• 2022
  • 2022-10-13 JP JP2024522419A patent/JP2024537382A/ja active Pending
  • 2022-10-13 ES ES22818104T patent/ES3008513T3/es active Active
  • 2022-10-13 EP EP22818104.6A patent/EP4415590B1/en active Active
  • 2022-10-13 WO PCT/IB2022/059827 patent/WO2023062582A1/en not_active Ceased
  • 2022-10-13 US US18/701,526 patent/US20240398153A1/en active Pending

Patent Citations (4)

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