FILTER HOLDER AND COFFEE MACHINE

Description

[0001] The present invention relates to filter holders for receiving a filter with extraction material, in particular coffee grounds, comprising a receiving part with a base and at least one through-opening on the base, on which a valve for opening and closing the through-opening is arranged, and a coffee machine.

[0002] US Patent 4,924,922 A discloses a brew-through lid for a coffee maker in which a valve on a filter holder is opened by inserting a vessel. The valve is biased into a closed position by a spring, but remains open due to the position of the vessel beneath the valve.

[0003] EP 2 700 337 B1 discloses a coffee machine with a filter holder that has an outlet at its base, which can be closed by a valve. The valve can be opened mechanically via a lever when a container is inserted under the filter holder, causing the lever to pivot and open the valve. With this mechanical solution, the contact time of the hot water on the coffee grounds can only be controlled manually. Due to the mechanical coupling, an unintended dripping of coffee, which may have absorbed more bitter substances due to a longer contact time, is unavoidable, as the valve remains open as long as the container is under the filter holder.

[0004] CN 108 309 054 discloses a coffee machine with a valve on a filter holder that can be moved via a control system, by means of which the outflow of the brewed coffee can be controlled.

[0005] Other coffee machines are shown under US 2015 / 0164265, DE 33 12 354, US2020 / 0121113 and DE 33 07 338.

[0006] It is therefore an object of the present invention to create a filter holder which has a valve arrangement which can be switched automatically.

[0007] This problem is solved with a filter holder having the features of claim 1.

[0008] According to the invention, the valve for opening and closing the through-hole at the bottom of the filter holder is movable by means of a linear actuator. This allows the duration that the extraction fluid and extraction material remain in the filter of the filter holder to be preset. After completion of the extraction process, the valve closes the through-hole, preventing any further fluid from escaping the filter holder. The linear actuator can be supplied with an electrical signal to change its opening state, i.e., to open or close the through-hole. This enables control based on sensor outputs, time, program sequences, or similar parameters.

[0009] Preferably, a cam body with at least one cam guide is provided between the valve and the linear actuator. This allows the movement of a movable part of the linear actuator to be redirected in a different direction. For example, the valve can be movable vertically and the movable part of the linear actuator horizontally, resulting in a very compact design.

[0010] According to the invention, the bottom-side through-opening is connected via a hose to an outlet on the underside of the filter holder for the discharge of an extraction liquid. This prevents contamination of the mechanics and electronics and ensures hygienic handling of the food. The hose can be made at least partially of an elastic material. This ensures a reliable seal at the ends of the hose. Furthermore, the hose can compensate for movement of the valve when opening or closing if the movable valve is connected to a section of the elastic hose via a drive element and a connector. When the valve moves, the hose can be compressed by the stroke of the valve, for example, with a stroke of between 3 mm and 10 mm, and in particular between 4 mm and 8 mm.For a particularly elastic design of the hose, it can include at least one bellows on an upper section between the through-opening and the connecting piece.

[0011] Preferably, a movable plunger of the linear actuator is passed through a tubular connector on the hose, which is movable in the vertical direction along with the valve. This allows the linear actuator and the cam body to be arranged on different sides of the hose for a compact design.

[0012] The linear actuator can preferably be fixed to an underside of the floor, wherein a movable plunger of the linear actuator is passed through a channel of a connecting piece on the hose, which is movable in a vertical direction together with the valve.

[0013] A closed cavity is preferably formed between the base and an underside of the filter holder with an outlet for the extraction fluid, in which the linear drive is fixed. This protects it from environmental influences.

[0014] The linear actuator is preferably designed as an energized electromagnetic solenoid. This allows for valve control with low energy consumption. Alternatively, the linear actuator can also be designed as an electrically driven spindle drive. Furthermore, the linear actuator can also be a hydraulic or pneumatic drive.

[0015] The solenoid that moves the valve assembly is preferably designed as a bistable linear magnet, since it has exactly two discrete stable states. These two states can be converted into the valve's open or closed states by connecting them to the valve assembly. A change of state in the linear magnet can be brought about by applying a short electrical pulse, for example, one millisecond long. This moves the plunger, within its plunger bearing, from one stable end position to the other, where it then remains.

[0016] The filter holder according to the invention is preferably detachably held on a coffee machine by means of a holder, i.e., removable, and can thus be easily removed for cleaning. The filter holder can be removed together with the linear drive, in particular the electromagnetic lifting magnet, which can optionally be detached from the filter holder.

[0017] Preferably, the filter holder has electrical contacts that are connected to electrical contacts on the holder, whereby electrical signals for switching the linear drive can be transmitted via the contacts. This allows, for example, the solenoid to be switched after electrical contacting.

[0018] The invention is explained in more detail below with reference to an exemplary embodiment and the accompanying drawings. These show: Figure 1 shows a side view of a coffee machine according to the invention with a filter holder; Figure 2 shows a view of a filter holder according to the invention without a coffee machine; Figure 3 shows a side view of the upper part of the filter holder with the valve arrangement; and Figure 4 shows a section through the side view of the filter holder. Fig. 3 .

[0019] A coffee machine 10 comprises a water tank 12, which is arranged on a housing 13 containing a control and operating unit. The water from the water tank 12 can be heated by a pump and a heating element and directed to a hot water inlet 16, which is located above a filter holder 1. The housing 13 includes a base plate 14 on which a vessel 15 is placed.

[0020] A filter, for example a filter paper insert containing an extraction material such as ground coffee or tea, can be placed in the filter holder 1. The filter holder 1 is mounted on a support 11 below the hot water inlet 16. The vessel 15, into which the extraction liquid from the filter holder 1 can be collected, is positioned below the filter holder 1.

[0021] Figure 2 and 3Figure 1 shows the filter holder 1 without the coffee machine 10. The filter holder 1 comprises a receiving part 2 with an upwardly open receptacle for a filter, which tapers towards a base 23. Ribs 22 or other positioning means are provided on the outside of the receiving part 2 for positioning it on the holder 11. An outwardly projecting handle section 26 is formed on an upper ring of the receiving part 2, with which the filter holder 1 can be removed from and inserted into the holder 11.

[0022] A valve assembly with a valve 4 for opening and closing a through-opening 3 is provided on the base 23 of the filter holder 1. The valve 4 is actuated by a linear actuator in the form of a solenoid 5. The solenoid 5 comprises a movable plunger 6 that moves a cam body 42 with cam guides 43, which is designed as a linearly movable slide 44. The slide 44 is movable along a linear guide of the filter holder 1. In the mounted position, the slide 44 is guided in a horizontal direction. The cam guide 43 can include an upper detent 47 and a lower detent 48, into which the driver 53 can engage in a stable position. Optionally, the cam guide 43 can also be designed only as a ramp without the detent 47 and 48.

[0023] The curved body 42 surrounds a hose 8 in a U-shape and has a curved guide 43 on each leg, in which a driver 53 is guided. The two drivers 53 are fixed to the hose 8 by a connecting piece 30.

[0024] In Figure 4 The filter holder 1 is shown in cross-section. The valve 4 is located on the base 23 at the through-opening 3 and seals it via a valve body in the closed position. The hose 8 is connected to the base 23 via an upper section 81, which is fixed to the connector 30 on the opposite side. The upper section 81 of the hose 8 includes a bellows, thus allowing vertical movement of the connector 30 relative to the base 23 without affecting the seal.

[0025] The connecting piece 30 is connected via a lower section 82 of the hose 8 to the outlet 7 on the underside of the filter holder 1. The lower section 82 also has a bellows to compensate for movement of the connecting piece 30 relative to the outlet 7.

[0026] The base 23 with through-hole 3 is connected to the outlet 7 via the hose 8, and the solenoid 5 is insulated from the liquid channel in the hose 8. The solenoid 5 is protected within a hollow chamber of the filter holder 1.

[0027] The receiving part 2 includes internal ribs 24 and for positioning a filter, for example a filter paper insert, in the receiving part 2. A cover 25 is fixed to the bottom 23 of the filter holder body 2, which surrounds the hose 8 and the lifting magnet 5.

[0028] The horizontally displaceable cam body 42, which is held on the linear guide 6 via the slide 44, acts on the drivers 53 via the cam guides 43. These drivers are attached to or integrally formed on the connecting piece 30. The connecting piece 30 includes a tubular passage 45 for the plunger 6 of the solenoid 5, the passage 45 being movable in the vertical direction relative to the plunger 6. For this purpose, the passage 45 can have an oval or elongated cross-section. The connecting piece 30 forms a movable unit with the valve body 41. The valve body 41 has an upwardly projecting pin and a cover for closing the through-opening 3.

[0029] The hose 8 comprises the upper section 81 made of an elastic material, which is attached to the connecting piece 30 by means of a lower ring 83 and fixed at its upper end to the through-opening 3 by a ring. The valve body 41 rests on the elastic ring for sealing in the closed position.

[0030] The lower section 82 of the hose 8 is fixed to the connector 30 by an upper ring 84 and forms a drain for the extraction fluid at its lower end. This allows the fluid to flow from the through-opening 3 inside the hose 8 to the outlet 7, and the hollow chamber around the hose 8 is protected from the fluid.

[0031] The solenoid 5 is fixed to the base 23 of the filter holder 1 and includes a plunger bearing that holds a plunger in two stable positions. To supply power to the solenoid 5, leads with electrical contacts are connected to these leads. When the filter holder 1 is inserted into the holder 11, these leads make contact with electrical contacts on the holder 11, allowing the solenoid 5 to be controlled programmatically to open and close the valve 4. This action can then be carried out by an extraction liquid, in particular coffee. Optionally, the solenoid and plunger 6 can be removed from the filter holder 1 for cleaning.

[0032] In the illustrated embodiment, a horizontal movement of the plunger 6 of the solenoid 5 is converted into a vertical movement of the valve 4. It is, of course, also possible to align the movement of the plunger 6 of the solenoid 5 not horizontally, but at a different angle relative to the movement of the valve 4. The actuation of the solenoid 5 can be program-controlled via the coffee machine 10.

[0033] In addition, the slide 44 can be formed with the cam body 42 on the connecting piece 30, so that the plunger 6 is connected to a driver that engages in the cam guide.

[0034] In the illustrated embodiment, the linear drive is designed as an energized electromagnetic solenoid. However, it is also possible to use a different linear drive, for example an electrically driven spindle drive, a hydraulic or pneumatic drive. Reference symbol list

[0035] 1 Filter holder 2 Mounting part 3 Through opening 4 Valve 5 Solenoid 6 Plunger 7 Outlet 8 Hose 9 Bellows 10 Coffee machine 11 Holder 12 Water tank 13 Housing 14 Base plate 15 Vessel 16 Inlet 22 Rib 23 Base 24 Inner rib 25 Cover 26 Handle section 30 Connecting piece 41 Valve body 42 Cam body 43 Cam guide 44 Slide 45 Feedthrough 47 Upper detent 48 Lower detent 53 Drive 81 Upper section 82 Lower section 83 Lower ring 84 Upper ring

Claims

1. Filter holder (1) for accommodating a filter with extraction material, in particular ground coffee, comprising a receiving part (2) with a base (23) and at least one base-side through-opening (3), on which a valve (4) for opening and closing the through-opening (3) is arranged, wherein the valve (4) can be moved by means of a linear drive (5), characterized in that the base-side through-opening (3) is connected via a hose (8) to an outlet (7) on the underside of the filter holder (1) for dispensing an extraction product.

2. Filter holder according to claim 1, characterized in that a cam body (42) with at least one cam guide (43) is provided between the valve (4) and the linear drive (5).

3. Filter holder according to claim 1 or 2, characterized in that the valve (4) is movable in the vertical direction and a plunger (6) of the linear drive (5) is movable in the horizontal direction.

4. Filter holder according to one of the preceding claims, characterized in that the hose (8) is made of an elastic material.

5. Filter holder according to one of the preceding claims, characterized in that the movable valve (4) is connected to an upper section (81) of the elastic hose (8) via a driver (53) and a connecting piece (30).

6. Filter holder according to claim 5, characterized in that the linear drive (5) is passed through the hose (8) by the connecting piece (30), which can be moved in the vertical direction with the valve (4) and the connecting piece.

7. Filter holder according to claim 5 or 6, characterized in that an upper section (81) of the hose (8) between the through-opening (3) and the connecting piece (30) comprises at least one bellows.

8. Filter holder according to one of the preceding claims, characterized in that the linear drive (5) is fixed to an underside of the base (23) and a movable plunger (6) of the lifting magnet (5) is passed through a passage (45) of a connecting piece (30) which is movable in the vertical direction together with the valve (4).

9. Filter holder according to one of the preceding claims, characterized in that a closed hollow chamber, in which the linear drive (5) is fixed, is formed between the base (23) and an underside of the filter holder (1) with an outlet (7) for the extraction liquid.

10. Filter holder according to one of the preceding claims, characterized in that the linear drive is designed as an energizable electromagnetic lifting magnet (5).

11. Filter holder according to claim 10, characterized in that the electromagnetic lifting magnet (5) is a bistable electromagnetic linear magnet with two discrete states and stable end positions.

12. Filter holder according to claim 2, characterized in that the cam body (42) engages in a U-shape around the hose (8) for conducting the extraction liquid and a cam guide (43) is formed in each case on the cam body (42) on opposite sides of the hose (8).

13. Coffee machine with filter holder (1) according to one of the preceding claims, characterized in that the filter holder (1) is detachably held on the coffee machine (10) by means of a holder (11).

14. Coffee machine according to claim 13, characterized in that the filter holder (1) has a closed hollow chamber in which the linear drive (5) is fixed.

15. Coffee machine according to claim 13 or 14, characterized in that the filter holder (1) has electrical contacts which are connected to electrical contacts on the holder (11) and via which electrical signals for switching the linear drive lifting magnet (5) can be transmitted.