DEVICE AND METHOD FOR FOAMING A LIQUID FOODSTUFF, ESPECIALLY MILK

• US 20110070349A1
• Filed: 09/20/2010
• Published: 03/24/2011
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: Franke Kaffeemaschinen AG (Michael Pieper, MBA)
• Original Assignee: Niro-Plan AG
• Inventors: Turi, Mariano, Kaiser, Andreas, Burri, Adrian, Vetterli, Heinz
• Granted Patent: US 8,657,262 B2
• Time in Patent Office: Days
• US Class Current: 426/474
• CPC Class Codes: A47J 31/4485 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

Abstract

A device for foaming a liquid foodstuff, especially milk, is provided including a pump (2) that has, on the suction side, a feed line (3) that can be connected in a fluid-conducting way to a storage container for the liquid foodstuff. An air feed line (3a) by which air can be fed to the foodstuff is arranged in a path of flow of the liquid foodstuff on the suction side of the pump (2) and, a throttle (4a) is arranged in the path of flow of the foodstuff on the downstream side of the pump (2). The air feed line (3a) includes an air valve (3b) that can be controlled by a control unit (9) and the air valve (3b) is an intermittent air valve (3b) having at least one state with high air flow and one state with comparatively lower air flow and/or with no air flow can be specified selectively by the control unit (9), and the control unit (9) and air valve (3b) are constructed to interact such that the average air flow of the air valve can be controlled through repeated switching between the at least two states of the air valve.

Claims

1. Device for foaming a liquid foodstuff, comprising:

a pump (2) that has, on a suction side, a feed line (3) that can be connected in a fluid-conducting way to a storage container for the liquid foodstuff,

an air feed line (3a) arranged in a path of flow of the liquid foodstuff, by which air can be fed to the foodstuff, is arranged on the suction side of the pump (2) and,

a throttle (4a) is arranged in the path of flow of the foodstuff, on a downstream side of the pump 2,

the air feed line (3a) comprises an air valve (3b) that can be controlled by a control unit (9) and the air valve (3b) is an intermittent air valve (3b) in which, through control of the control unit (9), is switchable between at least one state with high air flow and one state with comparatively lower air flow and/or with no air flow that can be specified selectively, and the control unit (9) and air valve (3b) are constructed to interact such that an average air flow of the air valve (3b) can be controlled through repeated switching between the at least two states of the air valve (3b).

2. Device according to claim 1, wherein the comparatively lower air flow and/or no air flow state is an essentially closed state and the high air flow state is an opened state, and the control unit (9) and air valve (3b) are constructed such that, through repeated switching between the closed and opened states of the air valve (3b), the average air flow of the air valve (3b) can be controlled.

3. Device according to claim 2, wherein the control unit (9) and air valve (3b) are constructed to interact such that the average air flow of the air valve (3b) can be controlled by specifying at least one of a switching frequency at which switching is performed between the at least two states of the air valve (3b) or a pulse-duty factor between the at least two states.

4. Device at least according to claim 3, wherein the air valve (3b) and the control unit (9) are constructed such that a switching frequency can be specified in a range from 1 Hz to 50 Hz.

5. Device according to claim 3, wherein the air valve (3b) and the control unit (9) are constructed such that the pulse-duty factor between the opened and closed states of the air valve (10) is DC 2% to DC 90% .

6. Device according to claim 3, wherein the control unit (9) comprises a storage unit for storing parameters of at least one foaming mode, and the foaming mode comprises at least one of a switching frequency or a pulse-duty factor.

7. Device according to claim 6, wherein the at least one foaming mode comprises two different values for the at least one of the switching frequency or the pulse-duty factor, and a time period for its use is allocated to each of the values or to each pair of the values.

8. Device according to claim 1, wherein the control device is connected to the pump (2) and interacts therewith such that the feed quantity of the pump (2) can be controlled by the control device, and the pump (2) is a gearwheel pump.

9. Device according to claim 6, wherein the foaming mode also comprises at least one of a foaming time period for an entire foaming process and at least one pump capacity for the pump (2).

10. Device according to claim 1, wherein the throttle (4a) is constructed as a controllable throttle (4a) and is constructed to interact with the control unit (9) such that at least two different flow cross sections can be specified selectively by the control unit (9) for the liquid foodstuff flowing through the throttle (4a).

11. Device according to claim 1, further comprising a foaming chamber (5) and a steam feed line (7), the steam feed line is connected in a fluid-conducting manner to the foaming chamber (5) and the throttle (4a) is connected to the foaming chamber (5) in a fluid-conducting manner downstream of the path of flow of the liquid foodstuff.

12. Device according to claim 11, further comprising a second air feed line (8) that can be closed selectively by a second air valve (10), the second air feed line is connected in a fluid-conducting manner to the foaming chamber (5), and the second air valve (10) is constructed to interact with the control unit (9) such that the air feed can be specified selectively by the control unit (9) for the second air feed line (8).

13. Device according to claim 12, wherein the second air valve (10) is an intermittent air valve (3b) having at least one state with high air flow and one state with comparatively lower air flow and/or with no air flow that can be specified selectively by the control unit (9), and the control unit (9) and second air valve (10) are constructed to interact such that N average air flow of the second air valve (10) can be controlled through repeated switching between the at least two states of the second air valve (10).

14. Method for foaming a liquid foodstuff, comprising:

feeding the liquid foodstuff is fed by a pump (2) that has, on the suction side, a feed line (3) connected in a fluid-conducting way to a storage container for the liquid foodstuff,

feeding air to the foodstuff via an air feed line (3a) arranged on a suction side of the pump (2) into a path of flow of the liquid foodstuff and feeding the liquid foodstuff,

repeatedly switching an intermittent air valve (3b) of the air feed line (3a) with a control unit (9) between at least one state with high air flow and one state with comparatively lower air flow and/or with no air flow for controlling an average air flow of the air valve (3b).

15. Method according to claim 14, wherein for regulation of the air valve (3b) by control unit (9), switching is performed repeatedly between an open state and an essentially closed state using at least one of a switching frequency or a pulse-duty factor.

16. Method according to claim 15, further comprising changing the air flow of the air valve (3b) according to a profile specified in the control unit (9) during a foaming process.

17. Method according to claim 16, wherein the liquid foodstuff is fed into a foaming chamber (5) downstream of the throttle (4a), and for producing hot milk foam, at least steam is fed by a steam feed line (7) to a foaming chamber (5), and for producing cold milk foam, air is fed to the liquid foodstuff on the suction side of the pump (2) by the air feed line (3a) and the liquid foodstuff is discharged via the foaming chamber (5) without a supply of steam.

18. Method according to claim 17, wherein for producing hot milk foam, air is fed to the foaming chamber (5) by a second air feed line on the pressure side of the pump.

19. Method according to claim 18, wherein for producing hot milk foam, the throttle (4a) is opened and for producing cold milk foam, the throttle (4a) is set into a throttling state in which a flow cross section for the liquid foodstuff is reduced by the throttle (4a) relative to an opened state.