coffee machine

Abstract

Coffee machine (1) comprising a water tank (23), a boiler (2) for generating steam, a water supply pump (3) for supplying water to the boiler (2) for generating steam, an external coffee dispenser (4), an external steam dispenser (5) with a dispensing opening (21) for dispensing a steam stream, a milk container (6) with an emulsifying device (7) for emulsifying the milk by means of the Venturi effect generated by the steam stream, wherein the emulsifying device (7) is integrated into a removable lid (18) of the milk container (6) and comprising a mixing chamber (10) for mixing milk / steam / air, a milk intake channel (12) by means of a Venturi effect with an inlet opening (11) into the mixing chamber (10), an air intake channel (14) by means of a Venturi effect with an inlet opening (13) into the mixing chamber (10),wherein the mixing chamber (10) has a sealed removable connecting opening (16) with the external steam dispenser (5) and an outlet opening (17) of the milk emulsion oriented towards the steam output opening (21) and is connected to an external dispenser (9) of the milk emulsion, wherein the outlet opening (17) of the milk emulsion is larger than the steam output opening (21) for activating the Venturi effect, characterized in that the minimum passage area of ​​the milk suction channel (12) has a diameter of not less than 5 mm, the output opening area (21) of the external steam dispenser (5) has a diameter between 0.5 mm and 2 mm, the outlet opening area (17) has a diameter between 2 mm and 5 mm, and the external steam dispenser (5) is designed to output a steam flow between 0.8 g / s and 1.2 g / s at a steam temperature between 110 °C and 130 °C and at a steam pressure between 0.5 and 2 atm.

Description

[0001] The present invention relates to a coffee machine.

[0002] Coffee machines are now widely available on the market and include a milk container with a Venturi-effect milk emulsifying device; such a device is disclosed, for example, in EP 3 162 257 A1.

[0003] These coffee machines are designed to produce an emulsion of hot milk in a cup.

[0004] In practice, the steam generated by a boiler of the coffee machine is fed into a mixing chamber provided in the emulsifying device, where the Venturi effect creates a vacuum that draws in milk from a suitable container for the milk and air from the outside atmospheric environment.

[0005] Typically, the temperature of the milk emulsion is significantly higher than the ambient temperature of 25 °C, because the steam required to trigger the Venturi effect also heats the milk.

[0006] In fact, a milk emulsion can typically be produced at a final temperature in the cup between 50 °C and 75 °C.

[0007] It has been found that the temperature of a food affects the perception of taste, which occurs in the taste buds of the tongue and is complemented by the aroma perceived by the receptors of the nasal mucus.

[0008] In fact, the temperature of the food or drink in the mouth changes the microscopic channels of the taste buds and the sending of the signal to the brain through the taste nerves.

[0009] Below 15 °C the taste buds are almost paralyzed, while at 37 °C the sensitivity of the taste buds increases more than 100-fold, and for this reason the sweet taste of an ice cream is only perceived when it melts in the mouth.

[0010] On the other hand, hot foods emit vapors that reach the nasal mucus and contribute about 80% to taste perception, but when the temperature exceeds 35°C, taste perception decreases because the burning sensation masks the taste nuances.

[0011] The technical objective of the present invention is therefore to create a coffee machine that is adapted to enhance the perception of the taste of the dispensed milk emulsion.

[0012] Within the scope of this technical task, one objective of the invention is to create a coffee machine suitable for dispensing a milk emulsion at a low temperature.

[0013] Another goal of the invention is to create a coffee machine with a milk emulsifying device that is easy to clean.

[0014] Another aim of the invention is to create a coffee machine with a kit of interchangeable milk emulsifying devices for producing a milk emulsion at low temperature and at high temperature.

[0015] The technical problem and these and other objectives according to the present invention are solved by a coffee machine according to the attached independent claim.

[0016] A milk emulsion stream is preferably discharged at a rate between 10 g / s and 15 g / s at a temperature that is no more than 20 °C higher than the temperature of the milk present in the milk container.

[0017] The container is preferably filled with milk at a temperature between 3 °C and 7 °C. The milk container preferably has thermal insulation.

[0018] The milk intake channel is preferably interchangeable with a milk intake channel having a smaller minimum passage area.

[0019] The coffee machine preferably has a cup tray, the external coffee dispenser is designed and arranged for direct dispensing into a cup positioned on the cup tray, and the external milk emulsion dispenser is designed and arranged for direct dispensing into the cup.

[0020] Further features and advantages of the invention will become clearer from the description of the coffee machine according to the invention, which is shown as an approximate and non-limiting example in the accompanying drawings. These show: - Fig. 1 the coffee machine with attached emulsifying device; - Fig. 2 the coffee machine with separate emulsifying device; - Fig. 3 a vertical section of the mixing chamber of the emulsifying device for the production of the cold emulsion of milk; - Fig. 4. The rotary knob with the valve means for producing the cold emulsion of milk; - Fig. 5 a vertical section of the mixing chamber of the emulsifying device for the production of the hot emulsion of milk; - Fig. 6. Turn the rotary knob with the valve means for producing the hot emulsion of milk.

[0021] With reference to the figures mentioned, a coffee machine is shown, which in its entirety is designated by the reference symbol 1.

[0022] The coffee machine 1 includes a water tank 23, a boiler 2 for generating steam, a water supply pump 3 for supplying water to the boiler 2 for generating steam, an external coffee dispenser 4, an external steam dispenser 5 and a milk container 6 with an emulsifying device 7 for emulsifying the milk by Venturi effect.

[0023] The external steam dispenser 5 is designed to output a steam flow between 0.8 g / s and 1.2 g / s at a temperature between 110 °C and 130 °C and at a pressure between 0.5 atm and 2 atm.

[0024] Preferably, the coffee machine 1 is designed to dispense the milk emulsion directly into the cup and for this purpose has a cup resting surface 8 on which the milk container 6 also rests.

[0025] In particular, the external coffee dispenser 4 is designed and arranged for direct dispensing into a cup positioned at the bottom of the cup tray 8, and the emulsifying device 7 has an external dispenser of the milk emulsion 9 which is also designed and arranged for direct dispensing into the cup.

[0026] The emulsifying device 7 has a mixing chamber 10 for mixing milk / steam / air, a milk intake channel 12 for drawing in the milk taken from the milk container 6 by Venturi effect and having an inlet opening 11 into the mixing chamber 10, an air intake channel 14 by Venturi effect with valve means 15 and an inlet opening 13 into the mixing chamber 10, a sealed removable connecting opening 16 with the external steam dispenser 5 and an outlet opening 17 of the milk emulsion connected to the external dispenser 9 of the milk emulsion.

[0027] The emulsifying device 7 is integrated into a pull-out lid 18 of the milk container 6, but in one version it can be integrated directly into the milk container 6.

[0028] The outlet opening 17 is positioned on the extension of the axis L of the external steam dispenser 5, while the milk inlet opening 11 and the air inlet opening 13 are arranged radially and on the side opposite the extension of the axis L of the external steam dispenser 5.

[0029] The milk suction channel 12 can consist at least partially of a structurally independent pipe section that is rigidly connected to the body of the mixing chamber 10 and extends to the bottom of the milk container 6.

[0030] The external dispenser of the milk emulsion 9 can consist at least partially of a structurally independent pipe section that is rotatably connected to the body of the mixing chamber 10 between a rest position and a dispenser position.

[0031] The valve means 15 can comprise a closure and a rotary knob 20 for its actuation, which is adapted to open or close the air intake duct 14 in an adjustable manner. In the case under investigation, the closure consists of a hollow shaft 30 that extends coaxially and is clamped to the rotary knob 20.

[0032] The hollow shaft 20 is in turn coaxially received in the air intake duct 14 and engages extensively in an inclined inner circumferential rib 31 of the air intake duct 14.

[0033] The inclined rib 31 can be formed on a removable section of the air intake duct 14.

[0034] The hollow shaft 20 is provided with an air inlet opening 22 in the air intake channel 14.

[0035] The air inlet opening 22 in the air intake duct 14 is designed as a slot extending in the axial direction of the hollow shaft 20.

[0036] Atmospheric air enters the cavity of the shaft 20 through the slot, and the cavity of the shaft 20 communicates directly with the inlet opening 13 for the entry of air into the mixing chamber 10.

[0037] The rotation of the rotary knob 20 around its axis varies the cutting position of the slot with the inclined rib 31 and then varies the section of the slot used for the entry of air into the intake duct 14.

[0038] The section of the slot used for the entry of air into the air intake duct 14 is actually the section that lies between the tip of the slot and the point where the slot intersects the rib 31.

[0039] The air intake duct 14 is closed when the inclined rib 31 is positioned at an upper tip of the slot.

[0040] Starting from this position, when the rotary knob 20 is turned, a progressively increasing section of the slot opens and then an inlet area for the entry of air into the air intake duct 14 grows progressively up to a maximum value.

[0041] Downstream of the slot, the air passage area along the air intake duct is equal to or greater than the aforementioned maximum value.

[0042] It is clear that the amount of the increase in the inlet area for air entering the air intake duct 14 is correlated with the width of the slot; the wider the slot, the larger the inlet area for air entering the air intake duct 14 and its maximum value. The milk intake duct 12 has a minimum passage area that is sufficiently large to ensure the output of a milk emulsion with a weight between 2% and 8%, or even better, between 3% and 6% greater than the weight of the milk drawn from the milk container 6, where the additional weight of the milk emulsion compared to the drawn-in milk is that of the condensed steam contained in the milk emulsion.

[0043] In particular, the milk suction channel 12 has a minimum passage area that is sufficiently large to ensure the output of a milk emulsion flow with a value between 10 g / s and 15 g / s.

[0044] The milk inlet opening 11 is circular and has a diameter of not less than 5 mm, preferably between 5 mm and 10 mm.

[0045] The milk suction channel 12 has a minimum internal cross-section that is no smaller than the milk inlet opening 11.

[0046] The dispensing opening 21 of the external steam dispenser 5 is circular and has a diameter between 0.5 mm and 2 mm, preferably between 0.5 mm and 1 mm, and is smaller than the outlet opening 17.

[0047] The air intake opening is circular and has a diameter between 0.2 mm and 1 mm.

[0048] As mentioned, the valve means 15 adjust the air passage area along the air intake duct 14.

[0049] The air inlet opening 22 in the air intake duct 14 has an equivalent diameter between 0.3 mm and 2 mm in a configuration with maximum opening.

[0050] The equivalent diameter is understood to be the diameter of a circular area that is the same size as the area of ​​the inlet opening 22 for the entry of air into the air intake duct 14.

[0051] The outlet opening 17 is circular and has a diameter between 2 mm and 5 mm, preferably between 2 mm and 2.5 mm.

[0052] The emulsifying device 7, using the Venturi effect, can therefore achieve a high milk suction efficiency with a drawn-in milk flow of no less than 10 g / s.

[0053] With the milk suction channel 12 dimensioned in this way, a milk emulsion is obtained at a temperature not exceeding 25 °C when the temperature of the milk present in the milk container 6 is between 3 °C and 7 °C.

[0054] To keep the temperature at a value significantly below the ambient temperature, the milk container 6 may have thermal insulation.

[0055] The milk emulsifying device may have interchangeable parts for dispensing a hotter milk emulsion.

[0056] In particular, the air adjustment valve means and preferably also the milk intake channel can be interchangeable.

[0057] The comparison between the in the Fig. 3 and Fig. 4 air adjustment valve means and the milk intake channel with the components shown in the Fig. 5 and Fig. The 6 methods shown illustrate the difference better, also visually.

[0058] In fact, to produce a hotter milk emulsion, the milk emulsion in the Fig. 5 and Fig. The milk suction channel shown in Figure 6 is used, which, with a smaller minimum passage area, for example at the end of the replaceable part, reduces the efficiency of milk suction through the Venturi effect.

[0059] Furthermore, valve agents can be used to produce a hotter milk emulsion, which are located in the Fig. 5 and Fig. Figure 6 illustrates and provides a smaller maximum passage area of ​​the inlet opening 22 for the entry of air into the air intake duct 14, as the slot has a reduced width.

[0060] These exchanges allow a milk emulsion to be produced with a final temperature in the cup between 50 °C and 75 °C.

[0061] The method for dispensing the milk emulsion increases the efficiency of milk suction through the Venturi effect by increasing the minimum passage area of ​​the milk suction channel to a value corresponding to dispensing a milk emulsion that is between 2% and 8% heavier than the weight of the milk drawn from the container, and a milk emulsion flow rate between 10 g / s and 15 g / s, compared to a conventional emulsifying device that produces a hotter milk emulsion.

[0062] In comparison to known emulsifying devices using the Venturi effect for drawing milk and air into the mixing chamber, the minimum passage area of ​​the milk suction channel is now increased to a value corresponding to the output of a milk emulsion at a temperature not exceeding 25 °C, when the temperature of the milk in the milk container is between 3 °C and 7 °C and the steam output by the external steam dispenser 5 has a temperature between 110 °C and 130 °C and a pressure between 0.5 atm and 2 atm.

[0063] The coffee machine thus designed is susceptible to modifications and variations. For example, the various openings disclosed above, even those disclosed as circular, may have a non-circular shape, and in this case, the diameter shall be understood as the equivalent diameter, i.e., the diameter of a circle that has essentially the same non-circular opening area.

[0064] Furthermore, the scope of protection of the claims should be extended to milk emulsions of animal or plant origin (e.g. cow's milk, soy milk, oat milk, rice milk, goat's milk, buffalo milk, sheep's milk, etc.). QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 3 162 257 A1

[0002]

Claims

[1] Coffee machine (1) comprising a water tank (23), a boiler (2) for generating steam, a water supply pump (3) for supplying water to the boiler (2) for generating steam, an external coffee dispenser (4), an external steam dispenser (5) with a dispensing opening (21) for dispensing a steam stream, a milk container (6) with an emulsifying device (7) for emulsifying the milk by means of the Venturi effect generated by the steam stream, wherein the emulsifying device (7) is integrated into a removable lid (18) of the milk container (6) and comprising a mixing chamber (10) for mixing milk / steam / air, a milk intake channel (12) by means of a Venturi effect with an inlet opening (11) into the mixing chamber (10), an air intake channel (14) by means of a Venturi effect with an inlet opening (13) into the mixing chamber (10),wherein the mixing chamber (10) has a sealed removable connecting opening (16) with the external steam dispenser (5) and an outlet opening (17) of the milk emulsion aligned with the steam outlet opening (21) and is connected to an external dispenser (9) of the milk emulsion, wherein the outlet opening (17) of the milk emulsion is larger than the steam outlet opening (21) for the activation of the Venturi effect, characterized by , that the minimum passage area of ​​the milk suction channel (12) has a diameter of not less than 5 mm, the output opening area (21) of the external steam dispenser (5) has a diameter between 0.5 mm and 2 mm, the outlet opening area (17) has a diameter between 2 mm and 5 mm, and the external steam dispenser (5) is designed to output a steam flow between 0.8 g / s and 1.2 g / s at a steam temperature between 110 °C and 130 °C and at a steam pressure between 0.5 and 2 atm. [2] Coffee machine (1) according to claim 1, characterized by , that the minimum passage area of ​​the milk suction channel (12) has a diameter between 5 mm and 10 mm. [3] Coffee machine (1) according to one of the preceding claims, characterized by , that the output opening area (21) of the external steam dispenser (5) has a diameter between 0.5 mm and 1 mm and the outlet opening area (17) has a diameter between 2 mm and 2.5 mm. [4] Coffee machine (1) according to any one of the preceding claims, characterized by , that the milk container (6) has thermal insulation. [5] Coffee machine (1) according to any one of the preceding claims, characterized by , that the milk intake channel (12) can be replaced by a milk intake channel with a smaller minimum passage area. [6] Coffee machine (1) according to one of the preceding claims, wherein a cup support surface (8) is provided, wherein the external coffee dispenser (4) is designed and arranged for direct dispensing into a cup which is positioned on the cup support surface (8), wherein the external milk emulsion dispenser (9) is designed and arranged for direct dispensing into the cup. [7] Coffee machine (1) according to any one of the preceding claims, characterized by , that the milk suction channel (12) consists at least partially of a structurally independent pipe section that is rigidly connected to the body of the mixing chamber (10) and extends to the bottom of the milk container (6). [8] Coffee machine (1) according to any one of the preceding claims, characterized by, that the external milk emulsion dispenser (9) consists at least partially of a structurally independent pipe section which is rotatably connected to the body of the mixing chamber (10) between a rest position and a dispensing position. [9] Coffee machine (1) according to any one of the preceding claims, characterized by , that the outlet opening (17) of the mixing chamber (10) is positioned on the extension of an axis (L) of the external steam dispenser (5), while the milk inlet opening (11) and the air inlet opening (13) are arranged radially and on the side opposite the extension of the axis (L) of the external steam dispenser (5).

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