coffee machine

Abstract

Coffee machine (1) with a control unit (2) and a milk suction line (3) and a milk suction lance (4) that can be coupled thereto, which is designed to be inserted into various milk containers (5) and to draw in milk (6), wherein at least one level sensor (7) for detecting a level in the milk container (5) and an evaluation / transmission unit (9) connected thereto for evaluating and transmitting the detected level to the control unit (2) are arranged in the milk suction lance (4).

Description

[0001] The present invention relates to a coffee machine with a control unit and a milk suction line as well as a milk suction lance that can be coupled thereto according to the preamble of claim 1.

[0002] From EP 2 568 858 B1, a coffee machine of this type is known, comprising a control unit, a milk suction line, and a milk suction lance connectable to it for insertion into a milk container and for drawing milk. Furthermore, the coffee machine has a monitoring device for monitoring the fill level of a milk container, which includes a fill level sensor located in the milk container and / or in the housing of a milk cooler and level-measuring electronics connected to it for generating a fill level information signal. The dispensing of milk and / or milk foam from the milk dispensing device can be controlled by the control electronics of the coffee machine depending on the fill level information signal generated by the level-measuring electronics.The level measurement electronics are located in or on the housing of the milk cooler, as is a transmitter for transmitting the level information signal generated by the level measurement electronics.

[0003] Another monitoring device for monitoring the fill level of a milk container is known from EP 2 241 241 A1.

[0004] From DE 10 2006 029 606 B4, a level sensor device for a reservoir with an outlet for storing an electrically conductive fluid in a household appliance is known. The level sensor device includes an electrical control unit comprising an evaluation circuit, a memory, and a power supply. The reservoir is made of an electrically conductive material, while the evaluation circuit compares the current flow or a corresponding physical quantity with a reference value stored in the memory. The known level sensor device is designed to be simple in construction and capable of monitoring a single level, for example, a minimum level.

[0005] From EP 2 020 198 B1, a method and a device for conveying foodstuffs, in particular milk, are known, comprising at least one pump by means of which the liquid foodstuff can be conveyed from a container. Furthermore, at least one sensor for measuring the fill level in the container is provided. The device is designed such that, depending on the sensor's measurement signals, the pumping process is interrupted when a predetermined measurement signal limit is exceeded or fallen below. The pressure sensor itself is arranged on the suction line and detects the pressure in it.

[0006] With conventional, state-of-the-art coffee machines, it is usually necessary to use milk in a designated milk container, which is either included with the machine or available as a separate accessory. In most containers, the sensor is located in or on the lid.

[0007] A disadvantage of current coffee machines is that it's not possible to dispense milk directly from a carton. Furthermore, since the milk container needs to be cleaned regularly, for example in a dishwasher, no milk can be dispensed or coffee drinks prepared during this time.

[0008] The present invention therefore deals with the problem of enabling the monitoring of a minimum fill level of milk, regardless of the milk container used.

[0009] This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject matter of the dependent claims.

[0010] The present invention is based on the general concept of arranging a level sensor for detecting the fill level in a milk container not in the milk container or the associated coffee machine itself, but in a milk lance that can be inserted into a wide variety of milk containers. This allows for the monitoring of various milk containers, including retail packaging, by means of the level sensor located in the milk suction lance. The coffee machine according to the invention comprises a control unit, a milk suction line, and a milk suction lance that can be connected to it for insertion into various milk containers and for drawing milk.According to the invention, at least one level sensor for detecting the fill level in the milk container and a connected evaluation / transmission unit for evaluating and transmitting the detected fill level to the control unit are arranged in the milk suction lance. The at least one level sensor does not detect the actual volume of milk present in the milk container, but only the fill level above a lower end of the milk lance. From this, the evaluation / transmission unit can calculate the amount of fluid or milk that can still be drawn in before the fill level falls below a suction opening located at the bottom of the milk suction lance. Although different container base areas result in a certain degree of inaccuracy, the accuracy of the determined fill level is entirely sufficient for standard retail packaging and milk containers to issue a warning message.For example, if the fill level sensor detects a fill level below a predefined limit, the evaluation / transmission unit assesses this and transmits a corresponding signal to the control unit, which can then generate a warning message, for example, visual and / or audible. For instance, a display can show that the milk container is almost empty and therefore needs to be replaced. With the coffee machine according to the invention, it is thus possible to detect the fill level of milk or, in principle, other liquids, regardless of the container used, so that, in particular, retail packaging for milk, for example, can be used directly with the coffee machine according to the invention.

[0011] In an advantageous embodiment of the solution according to the invention, the evaluation / transmission device has a contact element which can be connected to a mating contact element on the milk suction line of the coffee machine. This enables, for example, a wired signal transmission from the evaluation / transmission device to the control unit of the coffee machine. The contact element can, for example, be designed as a plug, while the mating contact element is designed as a corresponding and complementary coupling.Alternatively, two magnets can be arranged on the coffee machine in the area of ​​the mating contact element, while two corresponding metal elements are arranged on the contact element. These ensure a clear connection between the contact element and the mating contact element, thereby guaranteeing reliable contact when mounting the milk suction lance to the coffee machine. Both the plug and the coupling, as well as the magnets and the associated metal elements, ensure correct contact between the milk suction lance and the coffee machine.

[0012] In a further advantageous embodiment of the solution according to the invention, the evaluation / transmission device is designed for wireless data transmission to the control unit, for example via WLAN or Bluetooth. With such wireless data transmission, the contact elements and mating contact elements mentioned in the previous paragraphs can be dispensed with, thereby eliminating the need for both these and other cables within the coffee machine.

[0013] The evaluation / transmission unit advantageously includes a rechargeable energy storage device. Such a rechargeable energy storage device, for example a battery, is necessary to ensure the power supply of the evaluation / transmission unit. This battery can be charged, for instance, via appropriate contact elements on the coffee machine. A power supply can be implemented, in particular, via a so-called SELV (safety extra-low voltage) circuit, since the transmitted voltage is so low that there is no danger to an end user, even if they touch uninsulated contact surfaces. Alternatively, it is also conceivable that the rechargeable energy storage device could be charged, for example, by means of electromagnetic radiation, so that only its placement on the coffee machine is required, without any direct electrical contact.

[0014] In a further advantageous embodiment of the solution according to the invention, a temperature sensor is additionally arranged in the milk suction lance, which is also connected to the evaluation / transmission unit. In this case, the milk suction lance is not only able to monitor the fill level in an associated milk container, but also the temperature. This temperature can be used, for example, to control milk frothing, and it is particularly conceivable that the control unit could regulate the milk frothing process depending on the temperature of the milk detected in the milk container.

[0015] Further important features and advantages of the invention will become apparent from the dependent claims, the drawings and the associated description of the figures based on the drawings.

[0016] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own without leaving the scope of the present invention.

[0017] Preferred embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals refer to identical or similar or functionally identical components.

[0018] Each of these shows, schematically, Fig. 1 a sectional view through a coffee machine according to the invention in the area of ​​a milk suction lance, Fig. 2 and Fig. 3 a representation as in Fig. 1, but each with a modified milk suction lance.

[0019] According to the Fig. A coffee machine 1 according to the invention comprises a control unit 2 and a milk suction line 3, wherein a milk suction lance 4 can be coupled to the milk suction line 3. The milk suction lance 4 is designed for insertion into a machine that is only partially functional in the Fig. The milk suction lance 4 is schematically depicted as a milk container 5 and is designed for drawing milk 6 from it. According to the invention, at least one level sensor 7 for detecting the fill level in the milk container 5 and an evaluation / transmission unit 9, connected to it via lines 8, are arranged in the milk suction lance 4 for evaluating and transmitting the detected fill level to the control unit 2. The evaluation / transmission unit 9 comprises an evaluation unit 10 and a transmission unit 11, wherein the signals detected by the at least one level sensor 7 are evaluated in the evaluation unit 10 and transmitted by the transmission unit 11 to the control unit 2 either wired or wirelessly, for example via WLAN or Bluetooth.

[0020] The evaluation / transmission device 9 can have a contact element 12 which, in the case of a milk suction lance 4 arranged on the coffee machine 1, can be connected to a counter-contact element 13 on the milk suction line 3 (see Fig. 3) Naturally, the mating contact element 13 does not necessarily have to be located on the milk suction line 3, but can also be located at any other point on the coffee machine 1, provided that simple contact is possible when mounting the milk suction lance 4 on the coffee machine 1. Typically, the contact element 12 is designed as a plug and the mating contact element 13 as a socket, or vice versa.

[0021] Alternatively, two magnets can be arranged on the coffee machine 1 in the area of ​​the counter-contact element 13, while two associated metal elements are arranged on the contact element 12, which force a unique fixation of the contact element 12 on the counter-contact element 13 and thus a reliable contact.

[0022] If one considers the Fig. 2, it can be seen that a total of three level sensors 7 are arranged in the milk suction lance 4, which transmit a corresponding signal to the evaluation / transmission unit 9 when in contact with milk 6 or liquid in general.

[0023] The milk suction lance 4 is usually made of plastic, with both the lines 8 and the level sensors 7 or other sensors, for example a temperature sensor 14, being protected by being embedded in the plastic of the milk suction lance 4, in particular by being overmolded by it.

[0024] If one considers the fill level sensor 7 according to the Fig. 3, it can be seen that this comprises two electrodes 15 extending parallel over at least a part of the length of the milk suction lance 4, which together with the milk 6 or generally an electrolyte form a galvanic cell and thereby enable the detection of the fill level in the milk container 5.

[0025] If wireless data transmission from the evaluation / transmission unit 9 to the control unit 2 is to take place, an electrical energy storage device 16 is provided in the area of ​​the milk suction lance 4, in particular in the area of ​​the evaluation / transmission unit 9. This device may be designed, for example, as a battery or a rechargeable battery. The electrical energy storage device 16 can be charged with electrical energy, for example, wirelessly via an electromagnetic field, so that the electrical energy storage device 16 can be completely enclosed by the plastic of the milk suction lance 4 and thus be arranged in a particularly protected manner.

[0026] In general, the milk suction lance 4 and the coffee machine 1 according to the invention offer the significant advantage that the fill level can be detected in any type of container, regardless of its material, such as glass, metal, or a Tetra Pak. Furthermore, the milk suction lance 4 is extremely easy to handle and therefore user-friendly, and it contains no moving parts, resulting in comparatively high robustness. Due to the components 9, 16, 7, 8 being fully embedded in the plastic, the milk suction lance 4 can also be easily cleaned in a dishwasher. Depending on the selection of the sensors 7, 14 used, different equipment variants can also be easily differentiated.

[0027] Finally, it should of course be noted that the milk suction lance 4 does not have to be used exclusively for suctioning milk 6, but can suction almost any liquid, for example also syrup or water, so that the terms milk suction lance 4 and milk container 5 used in the previous paragraphs and in the claims can generally be used for a suction lance and a container with any liquid stored in it. Reference symbol list 1 coffee machine 2 Control unit 3 Milk suction line 4 milk suction lances 5 milk containers 6 Milk 7 Level sensor 9 Evaluation / Transmission Unit 10 Evaluation unit 11 Transmission device 12 Contact element 13 Counter contact element 14 Temperature sensor 15 electrode 16 Energy storage

Claims

[1] Coffee machine (1) with a control unit (2) and a milk suction line (3) and a milk suction lance (4) which can be coupled thereto, which is designed to be inserted into various milk containers (5) and to draw in milk (6), wherein at least one level sensor (7) for detecting a level in the milk container (5) and an evaluation / transmission unit (9) connected thereto for evaluating and transmitting the detected level to the control unit (2) are arranged in the milk suction lance (4). [2] Coffee machine according to claim 1, characterized by , that the evaluation / transmission device (9) has a contact element (12) which, when a milk suction lance (4) is arranged on the coffee machine (1), can be connected to a counter-contact element (13) on the coffee machine (1). [3] Coffee machine according to claim 2, characterized bythat the contact element (12) is designed as a plug and the mating contact element (13) as a coupling or vice versa. [4] Coffee machine according to claim 2, characterized by , that on the coffee machine (1) two magnets are arranged in the area of ​​the counter contact element (13), whereas on the contact element (12) two associated metal elements are arranged, which force a unique fixation of the contact element (12) on the counter contact element (13). [5] Coffee machine according to claim 1, characterized by , that the evaluation / transmission device (9) is designed for wireless data transmission to the control device (2), in particular via WLAN or Bluetooth. [6] Coffee machine according to any one of claims 1 to 5, characterized by , that a temperature sensor (14) is arranged in the milk suction lance (4), which is also connected to the evaluation / transmission unit (9) for communication purposes. [7] Coffee machine according to claim 6, characterized by, that the milk suction lance (4) is made of plastic and at least one line (8) between the evaluation / transmission device (9) and the at least one level sensor (7) and / or the temperature sensor (14) is embedded in the plastic of the milk suction lance (4). [8] Coffee machine according to one of the preceding claims, characterized by that the evaluation / transmission device (9) has a particularly rechargeable energy storage device (16). [9] Coffee machine according to any one of the preceding claims, characterized by , that the at least one level sensor (7) has two electrodes (15) extending parallel over at least a part of the length of the milk suction lance (4).

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