Automatic device for heating and frothing a liquid, in particular milk

• US 20040107843A1
• Filed: 07/09/2003
• Published: 06/10/2004
• Est. Priority Date: 06/23/2000
• Status: Active Grant

• Current Assignee: Rancilio Macchine Per Caffe' S.p.A.
• Original Assignee: Rancilio Macchine Per Caffe' S.p.A.
• Inventors: Oldani, Renzo, Bottelli, Eliano
• Granted Patent: US 6,840,163 B2
• Time in Patent Office: Days
• US Class Current: 99/452
• 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
• CPC Class Codes: A47J 31/4489 Steam nozzles, e.g. for introducing into a milk container to heat and foam milk
• CPC Class Codes: A47J 36/34 Supports for cooking-vessels
• CPC Class Codes: A47J 43/125 Receptacles with gas-introducing means at the bottom; Gas pumping means therefor

Abstract

An automatic device for heating and frothing a liquid, in particular milk, comprises a container (1) for the liquid, inside which a first tube (6) for introducing pressurised steam into the liquid is removably mounted. The first tube (6) has an inlet in correspondence of the bottom of the container (1), for receiving steam from a duct located within a support base (3) of the container (1), and is secured, for at least part of its length, to a second tube (7) for introducing air into the liquid.

Claims

1. An automatic device for heating and frothing a liquid, comprising a container (1) having a bottom to which means (6) for introducing pressurised steam into the liquid are removably connected, characterised in that said container (1) is arranged to co-operate with a support base (3) where steam feed means are provided to supply said introduction means (6) with steam produced by a source, so that steam enters said introduction means (6) from the bottom, and in that said steam introduction means (6) comprise a first tube (6) which is open at a first end, arranged in correspondence of the bottom of the container (1), to allow the connection with said steam feed means, and has a second end (64) which is closed and is substantially adjacent to the bottom of the container (1), a radial opening (65) being provided near said second end (64) for letting steam pass from said first tube (6) to the liquid.

2. A device according to claim 1, characterised in that said first tube (6) is removably connected to a fastening member (8) secured to the bottom of the container (1) and having an axial through-hole intended to receive said first end of the first tube (6).

3. A device according to claims 1 and 2, characterised in that said first tube (6) comprises at least a first section (60), secured to said fastening member (8) and having axis substantially parallel with the axis of the container (1), and an end section (63), also with axis substantially parallel with the axis of the container (1), comprising said second end (64) and said radial opening (65) and arranged adjacent to an internal wall of the container (1).

4. A device according to claim 3, characterised in that said first tube (6) further comprises a substantially rectilinear and downward inclined intermediate section (62).

5. A device according to any of claims 1 to 4, characterised in that said first tube (6) is associated with a second tube (7) for introducing air into the liquid, which second tube is open at both ends, is arranged within the container (1), is secured to the first tube (6) and is removable jointly therewith from the container (1).

6. A device according to any of claims 3 to 5, characterised in that said second tube (7) comprises a first section (70), substantially parallel with said intermediate section (62) of the first tube, and a second section (71), substantially parallel with the end section (63) of the first tube (6) and having an end portion (72) of reduced cross-sectional size, which has an air outlet opening (73) arranged in front of said radial opening (65) of the first tube so as to partly obstruct such opening.

7. A device according to any preceding claim, characterised in that said fastening member (8) has an outward projecting portion arranged to sealingly engage a cavity (12) of said base (3), an outlet (13) of said steam feed means being provided on the bottom of said cavity (12), in register with said axial hole (10).

8. A device according to any preceding claim, characterised in that said container (1) has, on the external surface of its bottom, tongues (14) arranged to engage openings (15) in said base (3) and to be retained, upon a rotation of the container (1) about its axis, by members (16) of the upper surface of the base itself, which define said openings (15).

9. A device according to any of claims 1 to 6, characterised in that said container (1) has on its external wall, projections (20) arranged to engage, upon a rotation of the container (1) about its axis, retaining members (21) upward projecting from the base (3) and to be retained by horizontal sections (21a) of said retaining members (21).

10. A device according to claim 9, characterised in that said base (3) has a set of freely rotatable ball supports (24) upon which the container (1) rests when placed on the base (3).

11. A device according to claim 10, characterised in that said ball supports (24) are resiliently supported within the base (3).

12. A device according to any of claims 9 to 11, characterised in that one of said ball supports (24) is arranged to co-operate with a safety switch located inside the base (3) so as to keep said switch is open when said projections (20) are not retained by the retaining members (21).

13. A device according to any of claims 9 to 12, characterised in that said base (3) has a central projection (26) housing an end portion (27) of said steam feed means, said projection (26) being arranged to sealingly engage a cavity (29) in the bottom of said container (1) so that an outlet (13) of the steam feed means is in register with an inlet of said first tube (6).

14. A device according to claims 2 and 13, characterised in that said cavity (29) is an axial cavity of said fastening member (8).

15. A device according to any preceding claim, characterised in that said base (3) has means (5) for controlling the steam flow in said steam feed means.

16. A device according to claim 15, characterised in that said means (5) for controlling the steam flow are carried by a control panel (23) mounted on a vertical stem (22) projecting from the base (3).

17. A device according to any preceding claim, characterised in that said steam feed means are connected with a source of pressurised steam internal to said base (3).

18. A device according to any preceding claim, characterised in that said steam feed means are connected with a source of pressurised steam external to said base (3), in particular with the source of pressurised steam of an espresso coffee machine.

19. A device according to any preceding claim, characterised in that said liquid is milk to be heated and frothed for the preparation of cappuccinos.