COFFEE MACHINE

Description

[0001] The present invention relates to a coffee machine with a container for coffee beans, a grinder to which coffee beans can be fed from the container, a filter holder into which ground coffee can be fed from the grinder via a chute, and a supply device for hot water that can be introduced into the filter holder, wherein a closure device with a rotatable flap is provided in the chute between the grinder and the filter holder, the flap being movable between an open and a closed position, the flap being rotatable about an axis that runs substantially parallel to a plane of the flap.

[0002] German patent DE 20 2004 007 182 U1 discloses a coffee machine in which a coffee grinder is arranged above a filter holder for receiving ground coffee. Ground coffee can be conveyed from the grinder into the filter holder via a chute, which can be closed by a shielding plate. The shielding plate is spring-loaded into the closed position and can be moved to an open position by a switch. This provides a degree of shielding, but a seal to the grinder is difficult to achieve because the shielding plate moves parallel to the sealing plane, leading to stress and wear on a sealing element at the sealing plane.

[0003] A similar separating device for a coffee machine is also disclosed in DE 20 2008 016 826 U1. In this separating device, a separating disc is movable along a seal in a drop chute between the coffee grinder and the filter holder. Here, too, abrasion can occur due to the movement of the separating disc relative to the seal.

[0004] WO 2007 / 106947 discloses a coffee machine with a grinder through which ground coffee can be fed into a filter holder. A pivoting flap for closing rests against the underside of a shaft in the closed position, resulting in an insufficient seal.

[0005] US Patent 4,913,037 discloses a grinding device with a receiving container for ground coffee, wherein a closure device with a pivotable flap is arranged in the chute for feeding ground coffee into the receiving container. The flap can be moved from below against a seal between the chute and a housing wall. A similar closure device for a coffee grinder is also disclosed in US Patent 2009 / 0031902, but without a seal between the chute and the closure flap.

[0006] WO 2019 / 174126 discloses a shaft with a closing flap that is pivotable relative to the seal, so that the closing flap slides along the seal during movement.

[0007] It is therefore an object of the present invention to create a coffee machine in which an improved seal is created between a grinder and a filter holder in order to avoid impairment of the grinder function.

[0008] This problem is solved with a coffee machine having the features of claim 1.

[0009] In the coffee machine according to the invention, a closure device with a rotatable flap is provided in the chute between the grinder and the filter holder. This flap is rotatable about an axis that runs substantially parallel to a plane of the flap, and an elastic seal is provided on the outer circumference of the flap. As a result, between the open and closed positions, the flap does not move parallel to the plane of the flap, which would cause a rubbing motion along the seal, but rather pivots towards or away from the closed position, moving towards or away from the sealing plane. This movement of the flap reduces wear on the sealing element and thus ensures a more reliable seal.

[0010] Preferably, the plane of the flap corresponds to a sealing plane in the closed position. The sealing plane can be defined, for example, by the flap or a seal of the flap resting against a shaft wall. This plane is essentially parallel to the axis of rotation of the flap, whereby the axis can also be arranged at a smaller angle to the plane of the flap, for example < 20°, in particular < 10°.

[0011] The flap preferably has a top surface in the closed position that is at least partially located in the shaft, wherein the top surface of the flap forms a wall section facing the inside of the shaft in the open position. This ensures that any coffee grounds on the flat top surface are ejected into the shaft when the flap is rotated into the open position.

[0012] In a preferred embodiment, the axis of the flap is arranged outside the shaft. This means that only a portion of the flap protrudes into the drop shaft in the closed position, in particular a portion that occupies less than 50% of the flap's surface area when viewed from above. This allows the actuating mechanism for the flap to be located outside the shaft, resulting in improved hygiene.

[0013] The flap is preferably rotated between the open and closed positions by an angle of between 60° and 120°, in particular 80° and 100°. The axis can extend in a horizontal plane in the upright position of the coffee machine, so that the flap can be moved from a horizontal closed position to a substantially vertical open position.

[0014] Preferably, a downwardly open receiving chamber is formed next to the chute, into which the flap can be at least partially inserted in an open position. This protects the flap in the open position, allowing the coffee grounds to be transferred directly from the chute into the filter holder. Preferably, in the closed position, the flap seals both the chute and the downwardly open receiving chamber, particularly in a steam-tight manner.

[0015] The flap is preferably designed in a substantially plate-like form, wherein, according to the invention, an elastic seal is provided on the outer circumference of the flap. According to the invention, this seal has a flexible sealing lip which, in the closed position, ensures a seal against a wall of the shaft.

[0016] The flap is preferably arranged such that, in the closed position, its underside faces the outside of the chute in an open position, so that the area that comes into contact with steam during coffee brewing is on the outside and coffee grounds cannot adhere to it. Preferably, the chute is designed to flare outwards below the flap, i.e., it is inclined to the vertical, for example at an angle between 20° and 60°, so that as little coffee grounds as possible adheres to this area of ​​the chute as it falls through.

[0017] The opening direction of the flap's rotation can be limited by a stop, preferably formed on the flap itself, which interacts with a wall of the shaft to prevent further rotation once the open position is reached. Similarly, when the flap is closed, a section of it can come into contact with a wall of the shaft to limit rotation, thus eliminating the need for additional stop elements.

[0018] For ease of manufacture, the flap can have an integrally formed bearing for receiving the axle, for example in the form of a sleeve-shaped bushing. The bearing housing can have a cross-section that deviates from a circular shape in order to be easily and rotationally fixed to the axle.

[0019] For efficient operation, the flap can be driven by a motor connected to the axle via a gearbox. The gearbox can be a gear drive, but it can also incorporate other drive elements.

[0020] To ensure good guidance of the coffee grounds exiting the grinder, the chute between the grinder and the filter holder can run at an angle, so that a chute is formed behind the grinder, which then leads into a vertical section of the chute.

[0021] The invention is explained in more detail below with reference to an exemplary embodiment and the accompanying drawings. These show: Figure 1 shows a view of the coffee machine according to the invention; Figure 2 shows a sectional view through the coffee machine in the area of ​​the chute with the flap open; Figure 3 shows a sectional view in the area of ​​the chute with the flap closed; Figure 4 shows a bottom view of the chute in the closed position; and Figures 5A and 5B show two detailed views of the flap with the axis.

[0022] A coffee machine 1 comprises a container 2 for holding coffee beans, which is arranged above a grinder 3. Below the grinder 3 is a filter holder 4, which holds ground coffee for brewing. The brewed coffee can be collected in a carafe 5 below the filter holder 4. The carafe 5 rests on a base 6 of a housing that includes a control unit 7. A water tank 8 is detachably attached to the housing. Water can be pumped from the tank to a heating element, and the hot water is then fed into the filter holder 4 via a supply line.

[0023] In Figure 2Figure 1 shows a sectional view through the coffee machine 1, depicting the area between the grinder 3 and the filter holder 4. The grinder 3 comprises two grinding discs 30 and 31, which are rotatable relative to each other and are used to grind the coffee beans from the container 2. The grinder 3 has an outlet 9 that leads to a chute 10. The chute 10 is angled and includes a chute 11 adjacent to the outlet 9 and a vertical section adjoining it. The chute 10 can also have a different geometry to convey the ground coffee from the grinder 3 into the filter holder 4.

[0024] A closure device with a rotatable flap 12 is arranged in the shaft 10. The flap is essentially plate-shaped and rotatable about an axis 13. The axis 13 is located outside the shaft 10, which is bounded adjacent to the axis 13 by a wall 14 that is essentially vertically oriented. Adjacent to the shaft 10 is a downwardly open chamber 15 into which the flap 12 can be at least partially inserted in an open position, so that the flap 12 is protected in the open position.

[0025] In Figure 3Figure 12 shows a closed position of the flap 12. By rotating the flap 12 about the axis 13 by approximately 90°, the flap 12 has been moved from a vertical position to a horizontal position. A top surface 19 of part of the flap 12 seals the chute 10 from above, while another part of the flap 12 seals the chamber 15. A bottom surface 20 of the flap 12 faces a space that can also be reached by steam during coffee brewing, so that the flap 10 prevents steam from entering the chute 10 and the chamber 15.

[0026] The flap 12 is essentially plate-shaped and includes a seal 17 on its outer circumference, which has a projecting, flexible sealing lip 18 that can be applied to a wall in the area of ​​the shaft 10. These lines of contact of the sealing lip 18 define a plane to which the axis 13 is essentially parallel.

[0027] The area of ​​the shaft 10 below the flap 12 is bounded by walls 16 which are designed to spread outwards, for example at an angle between 20° and 60° to the vertical, so that the coffee grounds falling down through the shaft 10 do not touch the walls 16 which can be covered with condensation during the brewing process.

[0028] A stop 24 is formed on the flap 12, which, in the open position, can abut a wall 14 of the shaft 10 to limit the rotational movement of the flap 12. The wall 14 forms the partition between the shaft 10 and the open receiving chamber 15 for receiving part of the flap 12.

[0029] When the flap 12 rotates in the closing direction, an upper surface 19 of the flap 12 forms a stop and can come into contact with the lower end face of the wall 14, so that this rotational movement is also limited.

[0030] In Figure 4The area of ​​shaft 10 with a closed flap 12 is shown from below. Walls 16 surround the flap 12 and are arranged in a spreading pattern. In plan view, the flap 12 is essentially square, but it can also be rectangular, oval, or have another geometry.

[0031] In the Figures 5A and 5B The flap 12 with the axis 13 is shown in detail. The essentially plate-shaped flap 12 has an integrally formed bearing 21, which serves to guide the pin-shaped axis 13. The bearing 21 does not have a perfectly circular cross-section, but rather a chamber 22 projecting radially from the axis 13, into which a driver 23 is inserted, which is connected to or integrally formed with the axis 13. This ensures that the flap 12 is rotationally fixed to the axis 13.

[0032] Furthermore, a block with stop 24 is fixed or integrally formed on axis 13, on which a pin 25 is provided for connection to drive means. The pin 25 can, for example, be coupled via a gear train to a motor or other drive, which is actuated by a control unit, in order to move the flap 12 into the open position when coffee beans are ground by the grinder 3 and then into the closed position before the brewing process.

[0033] In the illustrated embodiment, the axis 13 is arranged essentially centrally on the flap 12. It is also possible to arrange the flap 12 asymmetrically relative to the axis 13 in order to reduce the size of the downwardly open chamber 15. For example, the Figure 3 The section of flap 12 protruding to the left side from axis 13 may be shortened or omitted. Reference symbol list

[0034] 1 Coffee machine 2 Container 3 Grinder 4 Filter holder 5 Carafe 6 Base 7 Control unit 8 Water tank 9 Outlet 10 Shaft 11 Slide 12 Flap 13 Axle 14 Wall 15 Chamber 16 Wall 17 Seal 18 Sealing lip 19 Top 20 Bottom 21 Bearing 22 Chamber 23 Drive 24 Stop 25 Pin 30 Grinding disc 31 Grinding disc

Claims

1. Coffee machine (1) comprising: a) a container (2) for coffee beans; b) a grinder (3) to which coffee beans can be fed from the container (2); c) a filter holder (4) into which ground coffee from the grinder (3) can be fed via a chute (10); d) a supply device for hot water which can be introduced into the filter holder (4); e) wherein a closing device with a rotatable flap (12) is provided in the chute (10) between the grinder (3) and the filter holder (4), which flap is movable between an open and a closed position, f) wherein the flap (12) is rotatable about an axis (13) substantially parallel to a plane of the flap (12), characterized in that the flap (12) has a seal (17) disposed on the outer periphery and that the seal (17) has an outwardly projecting flexible sealing lip (18).

2. Coffee machine according to claim 1, characterized in that the plane of the flap (12) corresponds to a sealing plane in the closed position of the flap (12).

3. Coffee machine according to claim 1 or 2, characterized in that the flap (12) in the closed position has an upper side (19) arranged at least partially in the chute (10) and the upper side (19) of the flap (12) in the open position forms a wall portion facing an inner side of the chute (10).

4. Coffee machine according to one of the preceding claims, characterized in that the axis (13) of the flap (12) is arranged outside the chute (10).

5. Coffee machine according to one of the preceding claims, characterized in that the flap (12) is rotatable between opening and closing positions between 60° to 120°, in particular 80° to 100°.

6. Coffee machine according to any one of the preceding claims, characterized in that the axis (13) extends in a horizontal plane.

7. Coffee machine according to one of the preceding claims, characterized in that a downwardly open receiving chamber (15) is formed next to the chute (10), into which the flap (12) can be inserted in an open position.

8. Coffee machine according to claim 7, characterized in that the flap (12) in the closed position closes the chute (10) and the downwardly open receiving chamber (15).

9. Coffee machine according to any one of the preceding claims, characterized in that the flap (12), in the closed position, has an underside which, in an open position, faces the outside of the chute (10).

10. Coffee machine according to one of the preceding claims, characterized in that the chute (10) below the flap (12) is designed to spread open.

11. Coffee machine according to one of the preceding claims, characterized in that a stop (24) is formed on the flap (12), which stop can be placed against a wall (14) of the chute (10).

12. Coffee machine according to one of the preceding claims, characterized in that an integrally formed bearing (21) for receiving the axis (13) is formed on the flap (12).

13. Coffee machine according to one of the preceding claims, characterized in that the flap (12) is rotatable by means of a motor which is connected to the axis (13) of the flap (12) by means of a gear.

14. Coffee machine according to one of the preceding claims, characterized in that the chute (10) between the grinder (3) and the filter holder (4) is angular.