RU2814984C2 - Automatic coffee machine with device for cleaning coffee outlet channel - Google Patents

Abstract

FIELD: beverage preparation devices.

SUBSTANCE: invention relates to an automatic coffee machine (1) comprising control circuit (60), dosing head (50) comprising at least one coffee outlet (51), and brewing device (10), wherein brewing device (10) comprises brewing chamber (12) provided with upper opening (16) for receiving ground coffee, and pressure piston (14) configured to move between an upper retracted position, in which it is located above brewing chamber (12), and a lower seal position, in which it enters brewing chamber (12) through upper opening (16), wherein hot water is supplied to brewing chamber (12), by means of pump (9), wherein said chamber is communicated with at least one coffee outlet (51) via coffee discharge channel (30) extending through pressure piston (14). In accordance with the invention, to outlet channel (30), air conduit (40) is connected in the area of connection zone (49) located next to pressure piston (14), wherein air conduit (40) comprises electric valve (47), which is controlled by control circuit (60), moving it from air conduit (40) closing position to air conduit (40) opening position immediately after pump (9) stops end of coffee brewing, so that coffee in outlet channel (30) after stopping of electric pump (9) flows out under action of gravity force continuously after already dispensed coffee.

EFFECT: creation of an automatic coffee machine, which has a simple design and is economical to use.

10 cl, 4 dwg

Description

The present invention relates to the general technical field of automatic coffee machines comprising a brewing chamber connected to a dosing head by a coffee outlet channel, in particular to an automatic coffee machine comprising a coffee outlet channel cleaning device.

From document FR2802073 or FR2877556 an automatic coffee machine is known, comprising a control circuit, a dosing head containing at least one coffee outlet and a brewing device. The brewing device includes a brewing chamber having an upper opening for receiving ground coffee, and a pressure piston movable between an upper retracted position in which it is located above the brewing chamber and a lower sealing position in which it enters the brewing chamber through the upper opening. The brewing chamber is supplied with hot water by means of a pump and is hydraulically connected to at least one coffee outlet through a coffee outlet channel passing through the pressure piston.

However, at the end of coffee preparation, the brewed coffee remains in the dispensing channel. This remaining brewed coffee will be released at the start of the next batch of coffee.

Therefore, coffee made after stopping the automatic coffee machine for several hours or even several days contains old coffee residues that can change the taste of the coffee.

This phenomenon can be aggravated when making ristretto coffee, the cup volume of which is small, for example 20 milliliters. The remaining coffee may be about 10% of the coffee volume.

The object of the present invention is to eliminate the above-mentioned disadvantages and to provide an automatic coffee machine which guarantees a good result when preparing a cup of coffee and which is simple and ergonomic to manufacture.

Another object of the present invention is to provide an automatic coffee machine that is simple in structure and economical in use.

These problems are solved using an automatic coffee machine containing a control circuit, a dosing head containing at least one coffee outlet, and a brewing device, wherein the brewing device includes a brewing chamber equipped with an upper opening for receiving ground coffee, and a pressure piston configured movable between an upper retracted position in which it is located above the brewing chamber and a lower sealing position in which it enters the brewing chamber through an upper opening, wherein the brewing chamber is supplied with hot water by a pump and is fluidly connected by at least with one outlet for coffee through a coffee outlet channel passing through the pressure piston, characterized in that an air channel is connected to the coffee outlet channel in the area of the connection zone located next to the pressure piston, and also in that the air channel contains an electric valve, which is controlled by the control circuit, moving it from the closing position of the air channel to the opening position of the air channel immediately after stopping the pump at the end of brewing coffee, so that the coffee in the dispensing channel after stopping the electric pump flows out under the influence of gravity continuously following the already dispensed coffee.

The air channel refers to the air channel and the external air channel. Thus, when the electric valve is in the opening position of the air passage, the air passage is connected to the outside air. In other words, when the electric valve is in the air passage opening position, the connection area is connected to the air outside the automatic coffee machine, which air is under atmospheric pressure.

By a coupling zone adjacent to the pressure piston, it is meant that the coupling zone is less than four centimeters from the pressure piston, preferably less than one centimeter.

Thus, cleaning of the coffee outlet is carried out only under the influence of gravity. At the end of coffee preparation, only a small amount of coffee remains in the pressure piston up to the connection area.

In addition, when preparing coffee, the control circuit synchronizes the stopping of the electric pump and the opening of the electric valve, so that the coffee in the coffee outlet continues to flow out while maintaining its flow rate.

Thus, the user sees that the coffee is pouring continuously. As a result, the dispensing channel is cleared without the user noticing, since this does not lead to, for example, intermittent coffee dispensing.

Preferably, the air conduction path includes one end connected to the electric valve, and the connection area is located at a level lower than the level of the end connected to the electric valve, with the pressure piston being in a lower sealing position.

Thus, during the brewing process, coffee cannot rise through the air passage to the electric valve and therefore cannot interfere with its proper functioning.

Preferably, the N1 level difference between the end connected to the electric valve and the connection area is greater than five centimeters when the pressure piston is in the lower seal position.

Preferably, the air conduction channel has a length L between the connection area and the electric valve, the length L being greater than ten centimeters, preferably greater than twenty centimeters.

This device ensures that coffee does not reach the solenoid valve through the air channel.

Preferably, the dosing head can be moved in a vertical direction between an upper position and a lower position, and the connection area is located at a level higher than the at least one coffee outlet hole when the dosing head is in an upper position and when the pressure piston is in a lower sealing position.

In this way, cleaning of the coffee outlet can be carried out solely under the influence of gravity.

Preferably, when the dosing head is in the upper position and the pressure piston is in the lower sealing position, the difference N2 between the level of the at least one coffee outlet hole and the level of the connection area is greater than or equal to ten centimeters.

Preferably, the brewing chamber extends along a vertical axis and the coffee discharge channel includes a curved portion that extends from an upper surface of the pressure piston.

Preferably, the air conduction path includes a curved portion located above the curved coffee outlet portion, the curved air path portion with the curved coffee outlet portion at the level of the connection area adjacent to the upper surface of the pressure piston.

This arrangement of the curved portion of the air passage above the curved portion of the coffee discharge passage prevents coffee from entering the solenoid valve.

Preferably, the curved portion of the coffee discharge channel and the curved portion of the air conducting channel are arranged in a vertical plane.

The automatic coffee machine preferably comprises a milk frothing device equipped with a Venturi system for sucking milk and air from a steam supply channel, wherein the milk frothing device comprises an air channel supplying air to a Venturi system for sucking milk and air, said air supply channel being opened or closed by an electric valve, which is a three-way electric valve.

The electric valve thus performs two different functions:

opening and closing the air supply channel of the milk frothing device and opening and closing the air supply channel of the coffee outlet channel. This achieves a particularly economical design.

Preferably, the electric valve includes an air inlet opening having a diameter of less than 0.5 millimeters.

Such an opening makes it possible to obtain a frothing device that produces high-quality milk foam, and to carry out cleaning of the coffee discharge channel, so that the coffee in the coffee discharge channel flows continuously under the influence of gravity.

The invention will become better understood by reference to the non-limiting embodiment illustrated in the accompanying drawings, in which:

- Fig. 1 is a perspective view of an automatic coffee machine in accordance with one embodiment of the invention;

- figure 2 shows a schematic view of the automatic coffee machine shown in figure 1;

- Fig. 3 shows a partial perspective view with spatial division of the automatic coffee machine shown in Fig. 1, with the brewing device and the pressure piston in the upper position, showing the coffee outlet and air channels, as well as the dosing head;

- Fig.4 shows a sectional view along line IV-IV of the brewing device with a pressure piston in the lower position of the seal of the automatic coffee machine shown in Fig.3.

It should be noted that in this document, the terms “horizontal”, “vertical”, “bottom”, “top”, “longitudinal”, “transverse”, “high”, “low” used to describe the automatic coffee machine refer to the machine standing on the work surface in a use situation.

In the embodiment shown in Fig. 1-4, the automatic coffee machine 1 contains a reservoir 2 from which cold water is supplied, an electric pump 9 (Fig. 2) and a brewing device 10. The brewing device 10 contains a brewing chamber 12 into which ground coffee is supplied. coffee from a coffee grinder (not shown in the figures). The automatic coffee machine 1 includes a housing 3, a container stand 4 on which the container can be placed, and a height-adjustable dosing head 50. The dosing head 50 includes an outlet 51 for coffee. The container support 4 may, for example, comprise a grid for mounting the container and a drip tray. The dosing head 50 is slidably mounted between an upper position in which the user can place a large size cup on the container stand 4 and a lower position in which the user can place a small size cup on the container support 4. The dosing head 50 is movably mounted on a support plate 5 adjacent to the housing 3 (Fig. 3). The automatic coffee machine 1 includes a circuit 60 for controlling the preparation of a beverage, in particular coffee, in accordance with user commands.

As shown in FIGS. 2-4, the electric pump 9 powers two flash boilers 13, 53: a hot water boiler 13 and a steam boiler 53. The electric pump 9 contains an inlet connected to a reservoir 2, which is designed to supply cold water. The electric pump 9 includes an outlet connected to an electric valve 52, which allows water to be directed to the hot water production boiler 13 or to the steam production boiler 53. The brewing device 10 includes a housing 11 extending longitudinally along a vertical axis.

The housing 11 contains a boiler 13 and a brewing chamber 12 having an upper opening 16. The brewing chamber 12 is configured to accommodate a pressure piston 14 installed to move along a vertical axis using a drive mechanism. The boiler 13 is designed to heat water for preparing coffee in the brewing chamber 12. The housing 11 is located on the side of the single-acting hydraulic cylinder 17, containing the upper rod 18 (Fig. 4), the supporting arm 19, forming a console, the free end of which is connected to the pressure piston 14 , so that the stroke of the pressure piston 14 and the stroke of the hydraulic cylinder 17 are carried out in parallel directions. The pressure piston 14 moves between the upper retracted position, in which it is located above the brewing chamber 12, and the lower sealing position, in which it enters the brewing chamber 12 through the upper opening 16. In the lower seal position, the pressure piston 14 compresses the ground coffee entering the brewing chamber chamber 12, and forms a tablet of pressed ground coffee. The boiler 13 and the housing 11 are made in one piece from a heat-conducting material that contains an electric heating element 20; channel 21 for passing and heating water (Fig. 4), the input of which is connected through an electric pump 9 to a reservoir 2 for cold water, and the end 22 is brought to the bottom of the brewing chamber 12.

When the pressure piston 14 is in the lower seal position, the brewing chamber 12 is in fluid communication with the coffee outlet 51 of the coffee outlet channel 30. The coffee outlet channel 30 includes a coffee passage channel 31 located in the pressure piston 14. The coffee passage channel 31 exits the pressure piston 14 through the outlet 15. The electric pump 9 is adapted to create an upward circulation of water in the brewing chamber 12 to the outlet 15 and to the outlet 51 for coffee. Such an infuser 10 is described in more detail, for example, in PCT patent application WO9912456.

As shown in FIGS. 2 and 3, the automatic coffee machine 1 includes an air conducting channel 40 of a coffee discharge channel 30. The air conducting channel 40 is connected to the coffee discharge channel 30 in the area of the connection zone 49 located near the pressure piston 14. The air conducting channel 40 includes an electric valve 47 electrically connected to the control circuit 60. The electric valve 47 includes an air inlet port 48. The control circuit 60 controls the electric valve 47 from a closed position of the air passage 40, in which the air inlet port 48 is closed, to an open position of the air passage 40, in which the air inlet 48 communicates with the air passage 40. The control circuit 60 controls the electric valve 47 from an open position to a closed position. The air passage 40 has one end 45 connected to the electric valve 47. The connection area 49 is below the level of the end 45 connected to the electric valve 47, particularly when the pressure piston 14 is in the lower seal position. As shown in FIG. 2, the level difference N1 between the end 45 connected to the electric valve 47 and the connection area 49 is six centimeters when the pressure piston 14 is in the lower seal position. The connection area 49 is located above the level of the coffee outlet 51 when the dosing head 50 is in the upper position and when the pressure piston 14 is in the lower seal position. The difference N2 between the positions of the coffee outlet 51 and the connection zone 49 is ten centimeters when the dosing head 51 is in the upper position and when the pressure piston 14 is in the sealing position.

The coffee discharge channel 30 includes a curved portion 32 extending from the upper surface 23 of the pressure piston 14 from the outlet 15. The air conduction channel 40 has a curved portion 41 located above the curved portion 32 of the coffee discharge channel 30. The curved portion 41 of the air conduction channel 40 is connected to the curved portion 32 of the coffee discharge channel 30 adjacent to the connection area 49, in close proximity to the upper surface 23 of the pressure piston 14. When the dosing head 50 is in the upper position and the pressure piston 14 is in the lower position seal, the coffee outlet passage 30 is directed substantially downward from the upper end 33 of the curved portion 32 to the coffee outlet 51, and the air conduction passage 40 is directed substantially upward from the upper end 42 of the curved portion 41 to the electric valve 47. The coffee discharge passage 30 has a flexible part 34 between the upper end 33 of the curved part 32 and the dosing head 50. The air passage 40 has a flexible part 43 between the upper end 42 of the curved part 41 and the electric valve 47. Thus, the flexible parts 34, 43 allow the movement of the pressure piston 14 and the dosing head 50. As shown in FIG. 2, the automatic coffee machine 1 includes a milk frothing device 55 located at the dosing head 50. The milk frothing device 55 includes a Venturi system 54 for sucking milk and air from a steam source produced by a boiler 53. A similar milk frothing device is described, for example. , in document EP2606782. The milk frothing device 55 includes a milk supply channel 56, an air supply channel 57 and a steam supply channel 58 to the suction system. The air supply passage 57 is opened or closed by an electric valve 47, which is a three-way electric valve. The control circuit 60 controls the electric valve 47 from a closed position of the air supply passage 57, in which the air inlet port 48 is closed, to an open position of the air supply passage 57, in which the air inlet port 48 communicates with the air conduction passage 40. The control circuit 60 controls the electric valve 47 from the open position to the closed position of the air supply channel 57. Air supply channel 57 is open when preparing frothed milk drinks and closed when preparing hot milk drinks. The milk frothing device 55 includes an outlet 59 for milk-based drinks located adjacent to the outlet 51 for coffee. The air inlet hole 48 of the electric valve 47 has a diameter of 0.3 millimeters. During operation, the user configures the parameters of the control circuit 60 and begins preparing coffee. After a portion of ground coffee is supplied to the brewing chamber 12, the pressure piston 14 takes its lower sealing position, and the electric pump 9 is activated by the control circuit 60 to supply water through the boiler 13 to heat it, then through the ground coffee located in the brewing chamber 12 to prepare the coffee. and then into the coffee discharge channel 30 formed by the coffee passage channel 31 in the pressure piston, the curved portion 32 and the flexible portion 34. Then, the coffee flows through the coffee outlet 51 into a cup previously placed on the container stand 4 by the user. After the pump 9 has supplied an amount of water corresponding to the amount of coffee requested by the user, the control circuit 60 turns off the power supply to the pump 9 and moves the electric valve 47 from a closed position to an open position. Thus, air enters the connection area 49, so that the coffee in the coffee discharge channel 30 continues to flow out maintaining its flow rate. As a result, the coffee outlet channel 30 is completely cleared from the connection area 49 to the coffee outlet 51.

Of course, the invention is in no way limited to the embodiments described and illustrated, which are given by way of example only. Modifications remain possible, in particular with regard to the composition of various elements or substitutions with technical equivalents, without departing from the scope of legal protection of the invention.

In an alternative embodiment, the control circuit 60 includes a pinch valve that acts on the flexible air path portion to open or close the air path 40.

Claims (10)

1. An automatic coffee machine (1) comprising a control circuit (60), a dosing head (50) containing at least one coffee outlet (51), and a brewing device (10), wherein said brewing device (10) includes a brewing chamber (12) provided with an upper opening (16) designed to receive ground coffee, and a pressure piston (14) configured to move between an upper retracted position in which it is located above the brewing chamber (12) and a lower sealing position, in in which it enters the brewing chamber (12) through the upper opening (16), while said brewing chamber (12) is supplied with hot water by means of an electric pump (9) and is fluidly connected to at least one outlet (51) for coffee through the channel (30) for releasing coffee, passing through the pressure piston (14), characterized in that the channel (30) for releasing coffee is connected to a channel (40) for conducting air in the area of the connection zone (49), located next to the pressure piston (14 ), and in that the air passage (40) contains an electric valve (47), wherein the control circuit (60) regulates the electric valve (47) to move it from a closed position of the air passage (40) to an open position of the passage (40). ) conducting air immediately after stopping the electric pump (9) at the end of brewing coffee, so that the coffee located in the coffee outlet channel (30) after stopping the electric pump (9) flows out under the influence of gravity continuously following the already released coffee. 2. Automatic coffee machine (1) according to claim 1, characterized in that the air channel (40) has one end (45) connected to an electric valve (47), and the connection area (49) is located at a level below the level of the end ( 45) connected to the electric valve (47), with the pressure piston (14) in the lower seal position. 3. The automatic coffee machine (1) according to claim 2, characterized in that when the pressure piston (14) is in the sealing position, the difference between the level of the end (45) connected to the electric valve (47) and the level of the zone (49) connections are more than five centimeters. 4. Automatic coffee machine (1) according to any one of claims 1-3, characterized in that the air channel (40) has a length L between the connection area (49) and the electric valve (47), and the length L is more than ten centimeters. 5. Automatic coffee machine (1) according to any one of claims 1 to 4, characterized in that the dosing head (50) is configured to move vertically between an upper position and a lower position, and in that the level of the connection area (49) is located above than at least one coffee outlet (51) when the dosing head (50) is in the upper position and the pressure piston (14) is in the lower sealing position. 6. Automatic coffee machine (1) according to any one of claims 1 to 5, characterized in that the brewing chamber (12) extends along a vertical axis, and the coffee outlet channel (30) has a curved part (32) that extends from the upper surface ( 23) pressure piston (14). 7. Automatic coffee machine (1) according to claim 6, characterized in that the air channel (40) contains a curved part (41) located above the curved part (32) of the coffee outlet channel (30), wherein the curved part (41) of the channel The air conduction (40) is connected to the curved portion (32) of the coffee discharge channel (30) in the area of the connection zone (49), adjacent to the upper surface (23) of the pressure piston (14). 8. Automatic coffee machine (1) according to any one of claims 6, 7, characterized in that the curved part (32) of the coffee outlet channel (30) and the curved part (41) of the air channel (40) are located in a vertical plane. 9. Automatic coffee machine (1) according to any one of claims 1 to 8, characterized in that it contains a milk frothing device (55) equipped with a Venturi system (54) for sucking milk and air from the steam supply channel (58), while the device ( 55) for foaming milk contains a channel (57) for supplying air to the Venturi system (54) for suctioning milk and air, and the channel (57) for air supply is opened or closed by an electric valve (47), which is a three-way electric valve. 10. Automatic coffee machine (1) according to claim 9, characterized in that the electric valve (47) contains an air inlet hole (48) having a diameter of less than 0.5 millimeters.