APPARATUS AND METHOD OF FROTHING A QUANTITY OF MILK

Abstract

It is disclosed an apparatus for frothing a quantity of milk for preparing a beverage, the apparatus comprises: a platform (1) for supporting a jug (50) containing the quantity of milk to be frothed and a steam wand (10) configured for emitting steam, wherein either said platform (1) is tiltable around a horizontal axis (X, Y) or the steam wand (10) is tiltable around a horizontal axis and wherein said steam wand (10) and said platform (1) are reciprocally movable by a translational movement in the vertical direction one with respect to the other. Preferably, there is provided a translational vertical motion of the steam wand with respect to the jug and/or of the jug with respect to the steam wand.

Claims

1. An apparatus (AMF) for frothing a quantity of milk for preparing a beverage, the apparatus (AMF) comprising: a platform for supporting a jug containing the quantity of milk to be frothed and a steam wand configured for emitting steam and/or heated air, wherein either said platform is tiltable around a horizontal axis (X, Y) or the steam wand is tiltable around a horizontal axis and wherein said steam wand and said platform are reciprocally movable one with respect to the other.

2. The apparatus (AMF) according to claim 1, wherein said steam wand and said platform are movable one with respect to the other through a translational vertical motion of the steam wand with respect to the jug and/or of the jug with respect to the steam wand.

3. The apparatus (AMF) according to claim 1, further comprising a horizontal shaft and a motor connected to said shaft, wherein the shaft is also connected to the platform so that tilting of the shaft results into tilting of the platform.

4. The apparatus (AMF) according to claim 1, wherein said platform comprises a centering mechanism which is designed in such a way that a jug of a first diameter or a jug of a second diameter, which is higher than the first diameter, can be accommodated on said platform in a centered way.

5. The apparatus (AMF) according to claim 1, further comprising a linear actuator with a translation carriage for translating vertically said steam wand connected to said translation carriage.

6. The apparatus (AMF) according to claim 1, further comprising at least one of a IR temperature sensor arranged for sensing a temperature of a side wall of the jug and a IR milk temperature sensor arranged for sensing a temperature of the milk in the jug.

7. The apparatus (AMF) according to claim 1, further comprising a proximity sensor for measuring milk level in the jug.

8. The apparatus (AMF) according to claim 1, further comprising a radio-frequency identification, RFID, reader configured for reading a radio-frequency identification, RFID, tag in order to identify a size of the jug.

9. The apparatus (AMF) according to claim 1, further comprising a proximity sensor in order to identify a size of the jug.

10. The apparatus (AMF) according to claim 1, further comprising a three-way valve connected to a source of steam.

11. The apparatus according to claim 1, further comprising a display and means for selecting one of a plurality of parameters.

12. A method of frothing a quantity of milk for preparing a beverage, the method comprising: providing a jug with a quantity of milk therein; providing a supporting platform and placing the jug on said supporting platform; providing a steam wand emitting steam and/or heated air, wherein said steam wand and said supporting platform are reciprocally movable one with respect to the other from a first position wherein an end of the wand is not within said jug to a second position wherein said end of the wand is at least partially within said jug immersed in the quantity of milk; and causing emission of steam and/or heated air from said wand end while tilting at least one of said supporting platform and steam wand.

13. The method according to claim 12, further comprising moving the steam wand with respect to jug through a translational vertical motion of the steam wand with respect to the jug and/or of the jug with respect to the steam wand.

14. The method according to claim 12, further comprising IR sensing a temperature of a side wall of the jug and/or IR sensing a temperature of the milk in the jug.

15. The method according to claim 12, further comprising measuring milk level in the jug by a proximity sensor.

16. The method according to claim 12, further comprising means for identifying a size of the jug.

17. The method according to claim 12, further comprising discharging any condensate steam formed in steam tubing before starting a frothing cycle.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0058] The present invention will become clearer from the following description, provided by way of a non-limiting example, to be read with reference to the accompanying drawings, in which:

[0059] FIG. 1 is an isometric view of the frothing apparatus according to an embodiment of the present invention with the steam wand in its uppermost position and the liquid container support in horizontal position;

[0060] FIG. 2 is another isometric view of the frothing apparatus shown in FIG. 1;

[0061] FIG. 3 is a front view of the frothing apparatus shown in FIG. 1;

[0062] FIG. 4 is a cross section of the frothing apparatus shown in FIG. 1;

[0063] FIG. 5 is an isometric view of the frothing apparatus of FIG. 1 with the steam wand in its lowermost position and the liquid container support in horizontal position;

[0064] FIG. 6 is an isometric view similar to FIG. 5 with the liquid container support in tilted position;

[0065] FIGS. 7a, 7b and 7c show the user interface of the frothing apparatus according to an embodiment of the present invention;

[0066] FIG. 8 is a schematic view showing the connection between the frothing apparatus of the present invention and a coffee machine; and

[0067] FIG. 9 is a diagrammatic representation of a method according to the present invention.

DETAILED DESCRIPTION

[0068] A frothing apparatus according to an embodiment of the present invention is shown, in different configurations, in several of the attached figures. It should be remarked that only some parts of the apparatus, including those which are important for understanding the invention, are shown. Finally, the apparatus could take a different shape and it could be provided with a properly shaped housing.

[0069] FIG. 1 shows an embodiment of the frothing apparatus according to the present invention. The apparatus is globally indicated by reference number AMF.

[0070] The frothing apparatus AMF comprises a platform 1 for supporting a jug 50. Preferably, the platform 1 is round or substantially round. The diameter of the platform 1 is adapted to accommodate the bottom of the jug 50.

[0071] However, according to preferred embodiments of the present invention, the platform 1 is configured for accommodating a plurality of jugs, each having a different volume and a corresponding different bottom diameter. Preferably, the platform 1 comprises a centering mechanism for arranging the jug in a centered arrangement. According to one embodiment, the centering mechanism comprises three concentric round steps 1a, 1 b and 1c. Round step 1a is designed for accommodating a small size jug (for instance a 400 ml jug); round step 1b is designed for accommodating a medium size jug (for instance a 600 ml jug); and round step 1c is designed for accommodating a large size jug (for instance a 1000 ml jug). In the Figures, a small size jug is shown for exemplary purposes. Step 1c projects upwardly more than step 1b. In turn, step 1b projects upwardly more than step 1a.

[0072] In addition, or as an alternative, to concentric round steps, the centering mechanism could comprise magnetic devices or a conical platform.

[0073] Preferably, platform 1 is thermally insulated. According to one embodiment, platform 1 is lagged with a high friction polymer with the ability to withstand high temperatures of 100 C. or more. An adapted polymer could be Polyoxymethylene (POM), Polyvinyl chloride (PVC), Polyamide-Nylon (PA), Polytetrafluoroethylene (PTFE), Polyether ether ketone (PEEK), fluorocarbon (for instance Viton) FKM, or any combination thereof.

[0074] The supporting platform 1 is tiltable around a tilting axis X. Preferably, the tilting axis X is substantially horizontal. Tilting axis X can be directed as shown in FIGS. 1 and 4. However, tilting can equally be performed around an axis Y directed at a 90 with respect to or in any other arrangement.

[0075] Having reference to FIG. 4, preferably, tilting of the supporting platform 1 is carried out through a shaft 2 passing through the center of the supporting platform 1. Preferably, one end of the shaft 2 is connected to a stepper motor 3 and the other end of the shaft is supported by a bearing block 4 or the like.

[0076] According to one preferred embodiment, the supporting platform 1 can be at least partially disassembled for maintenance and/or cleaning purposes. For instance, as shown in FIG. 4, a screw 5 could be provided for connecting the platform 1 to the shaft 2. Instead of the screw 5, a magnetic arrangement could be provided. The magnetic arrangement provides a quick and easy mechanism for attaching/detaching the platform 1.

[0077] Preferably, the maximum tilting angle of the supporting platform 1 is of 15 degrees. Preferably, the tilting angle is 12 degrees. Preferably, the rotation speed of the supporting platform 1 can be of 1 rpm.

[0078] Preferably, the stepping motor 3 and the bearing block 4 are mounted on a plate 6, partially shown in the Figures.

[0079] According to a preferred embodiment, the platform 1 is at least partially enclosed in a drain container 7 for collecting any liquid which could accidentally come out from the jug during use. While not shown in the Figures, the top opening of the drain container 7 could be closed by a grid or a lid with (linear or curved) slots.

[0080] The apparatus according to the present invention further comprises a steam wand 10 made of stainless steel or other metal material. According to one embodiment, the steam wand is of performance touch type with two concentric tubes and the steam flowing from the inner tube. An insulating material could be provided in the space between the two tubes. In this way, the outer surface of the outer tube remains at a lower temperature and it can be grasped by the barista without running the risk to become injured. Preferably, steam wand 10 is connected to a steam generator or a steam boiler (not shown) of a coffee machine 12 by a tubing 11 (FIG. 8). Possibly, the tubing 11 is of flexible type as shown in FIG. 8. According to embodiments, the tubing 11 is at least partially made of a synthetic fluoropolymer of tetrafluoroethylene, polytetrafluoroethylene (PTFE).

[0081] A linear actuator 15 is mounted perpendicular to the plate 6. The linear actuator 15 could be hollow to accommodate cables and/or tubing, for instance steam tubing 11.

[0082] The linear actuator can be of any known type. For example, the PMI KM Mono Stage Actuator is deemed to be appropriate for the apparatus of the present invention. It is manufactured with a linear guide and ballscrew unit. Its design allows to save space, by combining the carriage of the linear guideway and nut of the ballscrew to a complete Carriage-Nut.

[0083] Carriage 151 is configured for a vertical movement substantially perpendicular to the plate 6. See double arrow Z. Steam wand 10 is connected to the sliding carriage 151. The linear actuator 15 can be electrical or hydraulic or pneumatic.

[0084] Thanks to the above arrangements, the steam wand 10 can be moved towards or away from the bottom of the jug 50 and the jug can be properly tilted around axis X while the steam is emitted from the wand. Both the translation and the tilting movements reproduce manual movements generally carried out by a barista while he/she is frothing milk in the jug 50. Tilting movement increases liquid circulation inside the liquid container 50 due to gravitation forces.

[0085] While the preferred movement is of the steam wand with respect to the jug, according to the present invention such movement can be replaced by a translation of the jug toward the steam wand.

[0086] The apparatus of the invention imitates the motion of highly skilled coffee machine operators hand. Consequently, the apparatus is designed to accommodate two fundamental automatic dynamic motions: vertical motion of the steam wand on Z axis and pivotal motion of milk container on the X axis. Preferably, no motion is required on the Y axis.

[0087] The combination between the vertical motion of the steam wand and the pivotal (tilting) motion of the milk container provide the dynamic range required to:

[0088] 1. froth/texture the highest quality of micro foam milk,

[0089] 2. froth/texture milk quantity of 120-600 ml,

[0090] 3. froth/texture milk to temperature range of 40-80 C.,

[0091] 4. froth/texture the milk with volume increase of 0-100%,

[0092] 5. froth/texture range of milk types, and

[0093] 6. froth/texture milk using different container sizes.

[0094] Preferably, the apparatus AMF of the present invention comprises a user interface 20 for displaying and/or setting and/or recalling operation parameters. The user interface 20 could comprise a display and any known means for selecting and/or entering parameters. Such means could include a keyword, a (LCD) touch screen, selection keys, selection knob(s), arrangements based on speech recognition or the like. By such means the user could select a specific setting, possibly stored into a memory. According to an embodiment, the end user is allowed to save ideal milk pre-sets on to dedicated buttons. The display could be in any part of the apparatus or it can be remote from it. For instance, it can be arranged on a separated coffee machine. The connection could be wired or wireless.

[0095] In the embodiment showed in the figures, the user interface comprises a display 21, a selection knob 22 and three preset buttons 23, 24 and 25. The information which could be displayed and/or set will be disclosed in the following.

[0096] According to preferred embodiments, one or more temperature sensors for detecting, directly or indirectly, the temperature of the milk during the frothing could be provided.

[0097] According to one embodiment, a first temperature sensor 30 is configured for detecting and/or monitoring an outer temperature of the liquid container. In other embodiments, the temperature sensor can be embedded to the jug. The first temperature sensor 30 could be an infrared sensor directed substantially horizontally towards the jug. Preferably, the first temperature sensor 30 is arranged in such a way that it senses the lower part of the jug where milk is certainly present.

[0098] In addition to, or instead of, the above first temperature sensor 30 a second sensor 31 could be provided. Second sensor 31 is configured for sensing the temperature of the milk in the jug. The second temperature sensor 31 could be an infrared sensor directed substantially vertically towards the milk surface in the jug. Preferably, the second temperature sensor 31 is protected and enclosed in a top housing projecting on the jug.

[0099] According to one embodiment, the apparatus AMF further comprises a proximity sensor (possibly ultrasonic) 32 for measuring milk level in the jug. As shown in FIG. 2, milk level proximity sensor could be arranged in the above top housing. This position maintains the components protected.

[0100] As said above, according to a preferred embodiment, the apparatus AMF is configured for accommodating jugs 50 having different sizes. Preferably, the size of the jug which is going to be used is detected by a RFID 35 reader which reads a radio-frequency identification (RFID) tag 36 on the jug or by ultrasonic sensor that determinates the size of the jug on the supporting platform 1. As it is known, RFID uses electromagnetic fields to automatically identify and track tags attached to objects and containing electronically stored information. Alternative embodiments (not shown) are based on bar code readers, QR code readers or any other code reader (with the bar/QR code being attached to the outer wall of the jug).

[0101] In addition (or in alternative) to the RFID reader 35, according to the present invention there is provided a proximity sensor (possibly ultrasonic) 40 for detecting the jug size. Possibly, the proximity sensor 40 is arranged at the lower part of the apparatus, so that it senses lower part of the jug.

[0102] The steam for the apparatus AMF for the present invention could be generated in any known manner. In one embodiment, the steam is generated at the apparatus. In other embodiments, the steam is generated remotely therefrom. Preferably, as shown in the schematic drawing of FIG. 8, the steam is generated at a coffee machine and is transported to the apparatus by steam tubing 11. Preferably, a 2-way solenoid valve 11a or a 2-way mechanical valve is provided at the steam generation point and a 3-way solenoid valve 11b is provided at the apparatus AMF.

[0103] The provision of the 3-way solenoid valve 11b is advantageous in that it allows to have a third way through which, when the barista so desires (possibly at the beginning of each new cycle) to discharge any condensate steam formed in the steam tubing 11. Advantageously, the condensate steam can be discharged in the drain container.

[0104] The provision of the 3-way solenoid valve 11b is advantageous in that it allows to have a third way through which, when the barista so desires (possibly at the end of each new cycle) to remove any overpressure possibly present in the steam wand.

[0105] Preferably, the apparatus according to the present invention comprises a microprocessor 60. The microprocessor 60 can be connected to a memory with pre-set programs configured to control one or more of the vertical position of the steam wand, the duration of steam supply, the steam pressure, the angle of pivoting of the jug and the tilting speed.

[0106] Preferably, the frothing process is started by the barista and is terminated upon reaching a certain condition. For instance, the process is terminated when the required temperature of jug surface is satisfied, and desired milk volume increase is satisfied. Preferably, when the frothing process is terminated, the steam wand returns to home position (uppermost position) and the platform tilts back to horizontal position.

[0107] The steam used in the apparatus according to the invention to texture the milk and increase its temperature may be incorporated in an existing coffee machine and/or an independent pressure vessel uniquely designed for the specific apparatus.

[0108] The frothing apparatus AMF of the present invention may be a separated apparatus or it might be used in conjunction with an automatic milk dispenser to fill the milk container.

[0109] FIGS. 1 to 4 show an embodiment of the apparatus in the home position wherein the platform is horizontal and not tilting and the steam wand is not emitting steam towards the milk into the jug. The home position can be either the position before starting the frothing of the milk or when the frothing has been completed.

[0110] FIG. 5 shows the steam wand into the jug but the platform horizontal. Finally, FIG. 6 shows the steam wand into the jug and the platform tilted with respect to the horizontal arrangement.

[0111] The maximum path of vertical travel for the wand could be about 300 mm.

[0112] FIG. 7 show some examples of interface of the apparatus according to the present invention. As shown, the display 21 can display one or more information among those sensed and detected by the various sensors disclosed above.

[0113] For instance (FIG. 7a), the display could indicate the size of the jug which is on the platform, among a small size jug, a medium size jug and a large size jug. In FIG. 7a, the medium size jug has been detected and the display so shows. Other information displayed could be: a volume of the milk in the jug (220 ml in the example of FIG. 7a) and the milk temperature (4 C. in the example of FIG. 7a).

[0114] FIG. 7b shows the display 21, selection knob 22, three preset buttons 23, 24 and 25 and a start button 26. Display 21 of FIG. 7b shows the same information of display 21 of FIG. 7a. It also shows a desired temperature of the milk (62 C.) at the end of frothing and the desired percentage of frothing (30%). It also shows the type of milk (skinny) which is frothing. The selected values and type of milk could be selected from a menu (not shown), possibly through the selection knob. Pre-selections could also be recalled by any of buttons 23, 24 and 25.

[0115] The apparatus of the invention could be designed so that it does not operate if some conditions are not fulfilled. FIG. 7c shows, as an example, an alarm condition. For example, the apparatus does not start operation if the amount of milk is insufficient. Another alarm could relate to a too high temperature of the milk.

[0116] The above mentioned (LCD) touch screen may be used in conjunction with a key pad. The controls and screen are preferably arrayed on angled panel which is easily visible to the user above or under the apparatus.

[0117] A reset button could be positioned in the front of the device in highly approachable location. Pressing this button will shut off the 2-way solenoid valve and stop the steam dispensed by the wand immediately. Also, the wand will return to home position (FIG. 1) and platform will tilt back to home position (FIG. 1).

[0118] FIG. 9 is a flow chart 100 of the method of frothing a quantity of milk for preparing a beverage according to the present invention. The method comprises: [0119] 101: providing a jug 50 with a quantity of milk therein; [0120] 102: providing a supporting platform 1 and [0121] 103: placing the jug 50 on said supporting platform 1; [0122] 104: providing a steam wand 10 emitting steam, wherein said steam wand 10 and said supporting platform 1 are reciprocally movable one with respect to the other from a first position wherein an end of the wand is not within said jug 50 to a second position wherein said end of the wand 10 is within said jug 50 immersed in the quantity of milk; and [0123] 105: causing emission of steam and/or heated air from said wand 10 end while tilting at least one of said supporting platform 1 and steam wand 10.