BREWING UNIT, BEVERAGE PREPARATION MACHINE, AND BEVERAGE PREPARATION SYSTEM

Abstract

The invention relates to a brewing unit of a beverage preparation machine, said brewing unit comprising a brewing chamber (10) and a brewing chamber surface (15), wherein the brewing chamber (10) is substantially rotationally symmetrical with respect to an axis (16) directed from a first brewing chamber half (11) to a second brewing chamber half (12). The brewing chamber (10) has a maximum axial extension (17) in the direction of the axis (16) which is smaller than the largest diameter (18) transverse to the axis (16). Furthermore, the brewing chamber (10) has a thickness (19) in the region of the axis (16) which is equal to or smaller than the axial extension (17).

Description

[0001] Brewing unit, beverage preparation machine, and beverage preparation system

[0002] The present disclosure relates to a brewing unit, a beverage preparation machine, and a system for preparing beverages according to the preambles of the independent claims.

[0003] Various capsule-based beverage preparation machines with brewing units and brewing chamber halves, as well as different methods for capsule management and beverage preparation, are known from the state of the art.

[0004] The object of the invention is to overcome the disadvantages of the prior art. In particular, a system is to be provided that allows simple operation by a user.

[0005] This object is achieved by the devices and methods defined in the independent patent claims. Further embodiments emerge from the dependent patent claims.

[0006] In the following, a capsule is understood to mean a capsule for preparing a beverage or a liquid food. The capsule can comprise a capsule body which is filled with a substance for preparing a beverage. However, a capsule should also be understood to mean a beverage substance which is encased in a shell. For example, the beverage substance can be compressed into a preferably spherical pellet and coated with a shell material or enclosed in a loose shell. Likewise, the capsule can also comprise a loose beverage substance in powder form which is enclosed in a shell.

[0007] A brewing unit disclosed here for a beverage preparation machine comprises at least a first and a second brewing chamber half. The brewing chamber halves are arranged such that they are movable relative to one another from a closed position for forming a closed brewing chamber into an open position in which a capsule can be inserted into the brewing chamber. The brewing unit has at least one, preferably two holding means which hold a capsule in position when the capsule is inserted in an intermediate position in the open position between the first and second brewing chamber halves and release it when the brewing chamber is closed. Before the capsule is released by the holding means, the first and second brewing chamber halves are spaced apart such that the brewing chamber halves cannot grasp a capsule, so that the capsule falls through between the brewing chamber halves if it is not held by the holding means.

[0008] This spacing of the two brewing chamber halves ensures that a capsule can be easily removed from the brewing unit once it has reached the intermediate position. Only the retaining elements need to be moved apart to release the capsule. Accordingly, if the capsule is accidentally inserted into the brewing chamber, it can be removed and stored for later use.

[0009] The distance between the brewing chamber halves can be at least 10% larger than a largest dimension or a largest diameter of a capsule intended for beverage preparation in the brewing unit before and / or after its extraction. A spherical or polygonal capsule for preparing a coffee portion can have a largest dimension or a largest diameter between 21 and 52 mm, preferably between 23 and 42 mm, particularly preferably between 25 and 30 mm. However, spherical or polygonal capsules with a largest dimension or a largest diameter of 50 mm + / - 10%, 26 mm + / - 10% or 23 mm + / - 10% are also conceivable, depending on the amount of beverage substance required for beverage preparation.

[0010] The capsule can be guided and held in the intermediate position and before release by the holding means in such a way that it has no mechanical contact with the first brewing chamber half and / or the second brewing chamber half.

[0011] By avoiding mechanical or physical contact between the capsule and the brewing chamber halves, easy insertion of the capsule is achieved. It also allows a capsule to be removed from the brewing unit after reaching the intermediate position without damaging the capsule. Accordingly, if the capsule is mistakenly inserted into the brewing chamber, it can be removed and stored without restriction for later use.

[0012] The brewing unit can have control means which interact with the holding means when the brewing chamber is closed such that the latter releases the capsule. Because the control means are directly connected to the brewing unit, a direct coupling of the movement of the brewing chambers with the holding means is easy to implement. Furthermore, the capsule does not have to be pushed out of the holding means; the holding means release the capsule automatically. The holding means can be mounted so that they can pivot about an axis and / or be displaced in an axial direction. In order for the brewing chamber halves to move together, the holding means must be moved away from the area between the brewing chamber halves. Moving them away is easy by pivoting about an axis and / or displacing them in an axial direction. The axis can also define the axial direction for the displacement.It is also conceivable, however, for the displacement to occur along an axis that runs at an angle to the pivoting axis. If the pivoting axis runs horizontally, at least the movement of the holding means in one direction can occur due to their gravity.

[0013] The holding means can be spoon-shaped. Spoon-shaped means that the holding means are concave on the side assigned to a capsule during intended use, in order to be able to at least partially grasp and / or grip the capsule. Thus, with only a slight intervention, the capsule can be grasped and held in the appropriate intermediate position. It goes without saying that the concave design of the holding means must be adapted to the shape of the capsule to be used.

[0014] Conventional capsules are usually gripped by holding means on a circumferential flange. In contrast to this gripping on a flange, the present holding means can be designed in such a way that they can grip a capsule without defined holding points. For example, capsules without a flange can be held in the intermediate position by the holding means. Spherical or cubic capsules are particularly conceivable. Capsules with any polyhedral shape or even cylindrical capsules can also be gripped by the holding means. Spherical, cubic or polyhedral capsules have the advantage that they do not have to be held aligned in the intermediate position.

[0015] The holding means can surround the capsule laterally in the intermediate position. The holding means are spaced apart from one another by a minimum distance corresponding to a maximum of 90% of the capsule diameter measured in the area where the capsule is surrounded. This ensures that the capsule, when held in the intermediate position, cannot under any circumstances slide between the holding means and fall out of the intermediate position. The capsule diameter in the area where the capsule is surrounded is determined by a cut through the capsule transversely to a direction of movement of the two brewing chamber halves relative to one another. The holding means preferably surround the capsule in an area of ​​at least 20° each. This ensures that the capsule can be held securely in the intermediate position.

[0016] The holding elements can be pre-tensioned against one another on the axis by means of a spring element. This pre-tension of the spring force can be used to determine the force with which a capsule that has been mistakenly inserted into the intermediate position when not in use can be removed from the intermediate position again. For example, a user may mistakenly insert an espresso capsule but would like to enjoy a long coffee. In conventional brewing units, the inserted capsule can only be removed from the brewing unit by closing the brewing chamber and reopening it. The user can therefore prepare just the espresso capsule with a larger amount of water, enjoy an espresso instead of a long coffee, or remove the capsule from the brewing unit without extraction but by piercing it.However, if the retaining elements hold the capsule in place simply by means of a slight, opposing spring force, the capsule can simply be pushed through the space between the brewing chambers. The capsule is not damaged or punctured and can be reused.

[0017] A further aspect of the present disclosure relates to a method for inserting a capsule into a brewing unit of a beverage preparation machine. The brewing unit has a first brewing chamber half and a second brewing chamber half, which are arranged to be displaceable relative to one another to form a brewing chamber. The brewing unit in turn has at least one, preferably two holding means for holding and positioning the capsule. During the method, the capsule is held by the holding means or by the holding means in an intermediate position between the two brewing chamber halves. When the brewing chamber halves move together, the holding means release the capsule, the capsule being grasped and aligned by one of the two or both brewing chamber halves. The brewing chamber halves move together and form a closed brewing chamber.The first and second brewing chamber halves are spaced apart before release by the holding means such that the brewing chamber halves cannot grasp the capsule if it is released prematurely by the holding means. If released prematurely, the capsule would fall between the two brewing chamber halves.

[0018] The capsule can thus be freely inserted into the intermediate position before the brewing chamber halves are brought together. A capsule inserted by mistake, for example, for preparing an espresso instead of a long coffee, can be removed from the intermediate position. To do so, simply overcome the retaining devices, for example, by pushing them apart.

[0019] The capsule cannot have any mechanical contact with the first and / or second half of the brewing chamber before being released by the holding means.

[0020] This allows an incorrectly inserted capsule to be removed from the intermediate position without damaging the capsule. Accordingly, the user can later use the "recovered" capsule without restrictions.

[0021] When the brewing chamber halves are brought together, the retaining elements can be moved axially along one axis, increasing the distance between the retaining elements. Axial displacement is easy to implement and can be precisely controlled.

[0022] The holding means can move along the axis against the force of a spring element. The holding means are thus pre-tensioned against one another, whereby a defined minimum distance can be provided between the holding means. By overcoming the spring force, a capsule held in the intermediate position by the holding means can be removed.

[0023] When the capsule is released, the holding means can pivot about an axis. The axis can be the same axis along which the holding means move. Alternatively, it can also be a different axis. By pivoting the holding means, they are simply removed from the area between the brewing chamber halves so that the brewing chamber can be closed. The pivoting movement can be upwards or downwards about a horizontally arranged axis. It is also conceivable for the axis to be aligned vertically and for the holding means to pivot sideways. The holding means can only perform a pivoting movement or only a moving movement. A combination of movements is also possible.

[0024] When the brewing chamber halves are moved apart, the holding means can pivot about the axis back into the position between the brewing chamber halves. In doing so, a capsule adhering to one brewing chamber half can be pushed away from the brewing chamber half. Preferably, such pivoting back occurs downwards, so that the capsule is pushed downwards out of the area between the brewing chamber halves due to gravity. The time of pivoting back into the position between the brewing chamber halves can be delayed, for example, only after the brewing chamber halves have reached their open position.

[0025] A further aspect of the present disclosure relates to a beverage preparation machine having a brewing unit as described above.

[0026] A further aspect of the present disclosure relates to a system for preparing beverages comprising a capsule and a brewing unit as previously described.

[0027] A further aspect of the present disclosure relates to a brewing chamber half for forming a brewing chamber with a corresponding second brewing chamber half of a brewing unit of a beverage preparation machine. The brewing chamber half has an inlet for introducing a brewing liquid for preparing a beverage and / or an outlet for discharging a prepared beverage. Furthermore, the brewing chamber half has at least one further access for introducing and / or discharging a rinsing liquid. The further access is preferably separate from the inlet and the outlet. If there is a single further access, this preferably serves to introduce and discharge the rinsing liquid. If there are two or more further accesses, the introduction and discharge can take place through separate accesses. The brewing unit can be designed as described above.

[0028] Such additional access to the brewing chamber half allows for easy cleaning and / or rinsing of the brewing chamber without the inlet and / or outlet for preparing the beverage coming into contact with the rinsing liquid.

[0029] The additional access can be equipped with a filter element. Using a filter element can prevent disruptive particles from being washed into the brewing chamber and subsequently negatively impacting the beverage preparation. It also prevents larger components of the beverage preparation, such as coffee particles, from being washed out through the additional access and damaging, clogging, or blocking any downstream valves.

[0030] The brewing chamber half can have an ejector for ejecting the capsule, which is designed to be movable relative to the brewing chamber half. This allows any capsule adhering to one of the brewing chamber half to be ejected after the beverage has been prepared and the brewing chamber has been opened. Such an ejector is particularly useful when the capsule is pierced using perforations attached to the brewing chamber half. Conventional capsules with a flange can be grasped at the flange and separated from the perforation. In the case of capsules without a stable flange or without a flange at all, a pierced capsule often remains stuck to the perforations and can then be moved away from them or stripped off using the ejector. Even with capsules with a shell, for example made of cellulose or alginates, an ejector is helpful for separating the capsule from the brewing chamber half or the perforation means.

[0031] The additional access can be located between the ejector and the brewing chamber half or can open between them. The movement of the ejector relative to the brewing chamber half ensures continuous self-cleaning of the additional access.

[0032] The filter element can be designed as a gap, preferably an annular gap, between the ejector and the brewing chamber half. The gap is preferably dimensioned such that no beverage substance can penetrate into the gap. The aforementioned movement between the ejector and the brewing chamber half actively prevents particles of the beverage substance from becoming trapped in the gap.

[0033] The gap can have a typical width of 200 pm; in particular, the width of the gap is between 50 pm and 500 pm, preferably between 100 pm and 350 pm, particularly preferably between 150 pm and 250 pm. This dimensioning prevents, in particular, the penetration of coffee particles that can arise during the extraction of a coffee capsule.

[0034] The brewing chamber half can have perforation means for perforating an inlet side or an outlet side of a capsule. The perforation means serve to pierce the capsule shell so that an extraction fluid can be introduced into the capsule or discharged from it. The perforation means are preferably arranged so as to be movable relative to the brewing chamber half. Due to the movable arrangement of the perforation means, the time at which a capsule is pierced can be deliberately controlled independently of the closing of the brewing chamber. For example, it is possible to arrange the perforation means on the outlet side of the capsule in such a way that they do not protrude into the brewing chamber. For example, the perforation means can be covered by the ejector on the outlet side. Accordingly, in a first extraction step, the capsule can first be pierced on the inlet side so that the beverage substrate to be extracted is wetted.Only in a subsequent step is the capsule opened, pierced, or perforated on the output side. This allows pressure to build up in the capsule before the actual extraction. For example, this makes it possible to pre-brew a coffee substance before the coffee beverage is prepared. It is also conceivable, however, for the perforation means to pierce the capsule simultaneously on the input and output sides. The perforation means are then exposed and not covered by an ejector.

[0035] The ejector can be arranged so that it can move relative to the perforation. This makes it possible to strip the capsule from the perforation even if the perforation is movable relative to the brewing chamber half.

[0036] The brewing chamber half can have at least one groove approximately in the middle, which runs from the ejector towards the corresponding second brewing chamber half. Such a groove makes it easier to detach the capsule from the surface of the brewing chamber or from the corresponding perforation means. A vacuum created between the wall of the brewing chamber and the capsule by retracting the perforation means or an injector plate or possibly by opening the brewing chamber can thus be specifically prevented. No beverage substance is drawn out of the capsule through the openings created by the perforation means, which could contaminate the brewing chamber. This groove can absorb any residual water during extraction, so that the residual water supports the capsule in the area of ​​the groove.

[0037] The groove can have a width between 0.2 mm and 3.0 mm, preferably 1.0 mm, and a depth between 0.2 mm and 3.0 mm, preferably 1.0 mm. These dimensions have proven to be optimal for the separation between the capsule and the brewing chamber without negatively affecting the behavior of the capsule in the brewing chamber during extraction.

[0038] A further aspect of the present disclosure relates to a brewing unit of a beverage preparation machine. The brewing unit has two corresponding brewing chamber halves. The brewing chamber halves are arranged to be movable relative to one another in order to be brought from an open position for ejecting and inserting a capsule into a closed position for forming a brewing chamber and for enclosing and extracting the capsule. At least one of the brewing chamber halves has an inlet for introducing a brewing liquid for preparing the beverage, and at least one brewing chamber half has an outlet for discharging a prepared beverage. Furthermore, at least one brewing chamber half has at least one further access for introducing and / or discharging a rinsing liquid. The brewing unit can be designed as described above.

[0039] Such an additional access in one half of the brewing chamber enables easy cleaning and / or rinsing of the brewing chamber without rinsing liquid getting into the inlet and / or outlet. The inlet and outlet can be arranged in the same brewing chamber half or in different brewing chamber halves. Likewise, the additional access can be arranged on one brewing chamber half together with the inlet or the outlet, or the additional access can be located together with the inlet and outlet in the same brewing chamber half. Furthermore, the additional access can be arranged in one brewing chamber half, while the inlet and outlet are in the other brewing chamber half. If there are several additional accesses, these can be arranged in both brewing chamber halves.

[0040] At least one of the brewing chamber halves can have perforation means for perforating an inlet side or an outlet side of the capsule and an ejector for ejecting and stripping the capsule from the perforation means. The ejector is arranged to be movable relative to the brewing chamber half and / or to the perforation means. In the open position, the ejector covers the perforation means such that they protrude only insignificantly. "Protrude only insignificantly" is understood here and below to mean that the perforation means do not hinder or damage a capsule during insertion and / or ejection from the brewing chamber.

[0041] A further aspect of the present disclosure relates to a method for ejecting a capsule from a brewing unit, as described above, of a beverage preparation machine. During the relative movement of the brewing chamber halves from the closed position to form a brewing chamber and to enclose and extract the capsule into the open position for ejecting and inserting the capsule, the brewing chamber halves will move away from each other in a first step. In a further step that is at least partially simultaneous or subsequent, the perforation means move relative to the ejector until they protrude at most insignificantly or no longer protrude at all. By the relative movement between the ejector and the perforation means only when the brewing chamber is open, it can be determined in which of the brewing chamber half the capsule remains and is only subsequently released.Additionally, the perforation means can be designed in such a way that the capsule deliberately remains stuck on the perforation means. For example, barbs can be provided, or the perforation means can have a neck that is thinner than the tip. Accordingly, detachment from this perforation means must be deliberately assisted, for example, by the ejector.

[0042] The ejector can move relative to the brewing chamber half in such a way that it protrudes from a surface of the brewing chamber half. This has the advantage that the capsule is not only released from the perforation, but is also simultaneously detached from the brewing chamber half and pushed away.

[0043] The ejector can only move relative to the brewing chamber half when the brewing chamber halves are already in the open position or just before reaching the open position. This allows the capsule to exit directly from the area between the brewing chamber halves without further contact with the brewing chamber halves. Re-jamming of the capsule or contamination of the brewing chamber halves is prevented.

[0044] The ejector can move relative to the brewing chamber half in such a way that it does not protrude from the brewing chamber half. A fresh capsule can thus be inserted unhindered.

[0045] A further aspect of the present disclosure relates to a beverage preparation machine with a brewing unit as described above. A further aspect of the present disclosure relates to a beverage preparation system comprising a capsule and a brewing unit as described above.

[0046] A further aspect of the present disclosure relates to a beverage preparation machine comprising a brewing unit, in particular as described above, a pump, a first and a second fluid line and a controller. The brewing unit has two corresponding brewing chamber halves which are arranged to be movable relative to one another. The brewing chamber halves can be brought from an open position for dispensing and inserting a capsule into a closed position for forming a brewing chamber and for enclosing and extracting the capsule. The brewing chamber has an inlet for introducing an extraction liquid, an outlet for dispensing the prepared beverage and at least one further access for rinsing the brewing chamber. The further access is separate from the inlet and the outlet. The pump serves to convey the extraction or rinsing liquid.The first fluid line is arranged between the pump and the inlet and has a first valve for opening and closing the first fluid line. The second fluid line is arranged between the pump and the at least one further inlet and is provided with a second valve for opening and closing the second fluid line. At least one of the valves and / or the pump can be controlled by the controller.

[0047] The further access to the brewing chamber enables easy cleaning and / or rinsing of the brewing chamber without the rinsing liquid being fed into the brewing chamber through the inlet and / or outlet and / or being discharged from the brewing chamber. The beverage preparation machine can comprise a third fluid line between the at least one further access and a collecting container with a third valve for opening and closing the third fluid line. Such a third fluid line with the corresponding valve allows the rinsing liquid to be discharged from the brewing chamber into the collecting container. Thus, the rinsing liquid does not have to flow out via the outlet of the brewing chamber.

[0048] The first and / or second and / or third valves can be actively controlled by the control system. Solenoid valves or motor valves are conceivable for this purpose. Thus, for example, when filling the brewing chamber with a rinsing liquid, the second valve can be opened while the third valve remains closed. After a certain exposure time, the second valve can then be closed and the third valve opened to drain the rinsing liquid.

[0049] The first valve can be designed as a self-opening pressure valve. This ensures that no rinsing liquid enters the first fluid line or a capsule inserted in the brewing chamber. The rinsing liquid can thus be injected under pressure into the brewing chamber via the at least one additional access, as long as the pressure remains below the pressure required to open the first valve.

[0050] The first valve can have a hysteresis and open in particular at a pressure between 3 bar and 14 bar, preferably between 5 bar and 12 bar, particularly preferably between 7 bar and 9 bar, and close in particular at a pressure between 0.5 bar and 5.0 bar, preferably 2 bar. There should be a pressure gradient between the opening pressure and the closing pressure of at least 1 bar. Such a hysteresis ensures that the extraction only begins above a certain pressure and is stopped again at a low pressure. Dripping of the extraction liquid into the brewing chamber can be avoided. Such a hysteresis can of course also be created via the control system with a controlled first valve. A controlled valve allows the switching time to be set independently of the applied pressure. The process sequence can therefore be freely designed.In addition, defined intermediate positions can also be realized.

[0051] The beverage preparation machine can have a fourth valve for opening and closing a beverage outlet. The beverage outlet is understood to be a fluid line which extends from the outlet of the brewing chamber to a dispensing opening of the beverage preparation machine. For example, the fourth valve can be a self-opening pressure valve which opens in particular at a pressure between 1 bar and 12 bar, preferably between 3 bar and 10 bar, particularly preferably between 6 bar and 9 bar. Such a valve only allows beverage extraction above a preset pressure. When preparing a coffee, for example, it is important that the extraction takes place under a certain pressure. Otherwise the coffee will suffer noticeable losses in quality.It also prevents any rinsing liquid from flowing from the beverage outlet to the dispensing opening and thus into a cup provided by a user. This valve also enables any air volume trapped in the brewing chamber to be compressed in order to be able to fill the closed brewing chamber with the rinsing liquid and then empty it again. The fourth valve can also be a valve actively controlled by the controller. The beverage preparation machine can comprise a hydraulic pressure piston with an injector plate, the injector plate being part of one brewing chamber half. This pressure piston is arranged between the pump and the first valve in such a way that the pressure piston moves the injector plate and thus part of one brewing chamber half. The volume of the brewing chamber is reduced before the first valve opens. A capsule trapped in the brewing chamber is deformed.Particularly in the case of a capsule which contains a pressed tablet, deformation of the capsule is necessary in order to break up the beverage substance compressed in the pressed tablet. This is the only way to ensure even extraction of the beverage substance. The hydraulic force of the pressure piston can be determined by the effective diameter of the pressure piston and the pressure required to open the first valve. The shape and movement of the injector plate can be matched to a capsule held in the brewing chamber in such a way that the beverage substrate of the capsule is broken up. In this case, a crack structure or other features, such as perforations, can be introduced into part of a shell or surface material of the capsule. At the same time or alternatively, the injector plate can also serve to compress the beverage substrate so that it has a uniform density suitable for extraction.

[0052] The pressure piston can increase the contact pressure between the two halves of the brewing chamber. Accordingly, less force can be applied to close the brewing chamber while maintaining the same sealing effect. The movement of the brewing chamber halves is significantly reduced.

[0053] Another aspect of this revelation concerns a

[0054] Method for preparing a beverage with a beverage preparation machine, in particular as described above, comprising the steps: a) inserting a capsule into the brewing chamber, b) closing the brewing chamber, c) filling the brewing chamber with a rinsing liquid through a further access, d) draining the rinsing liquid from the brewing chamber to a collecting container, e) introducing an extraction liquid through an inlet, which is different from the further access, into the brewing chamber so that it flows into the capsule.

[0055] Using such a process, a capsule can be wetted in the brewing chamber without the rinsing liquid coming into contact with the prepared beverage. For example, a capsule shell, which is particularly hygroscopic, can be wetted in this way. At most, the physical properties of the capsule shell can be influenced as a result. For example, the capsule can be perforated more easily through contact with the rinsing liquid. It is also conceivable that the elasticity or extensibility of the capsule shell could be increased, particularly when rinsing with a particularly hot rinsing liquid.

[0056] Steps c) and d) can be repeated once, twice, three times, or more times. Depending on the material of the capsule shell and the desired effect, multiple repetitions may occur. Steps d) and e) can be performed at least partially simultaneously. Particularly with a flexible capsule shell, drainage of the rinsing liquid from the brewing chamber is assisted by expanding the volume of the capsule when the extraction liquid is injected into the capsule.

[0057] Before the extraction liquid is introduced into the capsule, the size of the brewing chamber can be reduced and the capsule deformed. For this purpose, it is advantageous if the capsule shell is designed to be flexible and stretchable so that the shell does not break open and the beverage substance is not released. Particularly when the capsule contains a pressed tablet, the pressed tablet can be broken up by reducing the volume of the brewing chamber, so that a uniform extraction can then take place. The size and shape of the brewing chamber can be matched to a capsule accommodated in the brewing chamber so that the beverage substrate of the capsule is broken up. In this case, a crack structure or other features, for example perforations, can be introduced into part of a shell or a surface material of the capsule.At the same time or alternatively, the reduction of the brewing chamber volume can also serve to compact the beverage substrate so that it has a uniform density suitable for extraction.

[0058] As the extraction liquid is introduced through the inlet into the capsule, the volume of the capsule can expand. Although the capsule can adapt to the volume of the brewing chamber simply by reducing its size, this adaptation of the capsule volume to the volume of the brewing chamber is further intensified as the extraction liquid is introduced. The capsule is pressed against the wall of the brewing chamber by the pressure prevailing inside the capsule. A further aspect of the present disclosure relates to a system for beverage preparation comprising a capsule and a beverage preparation machine as described above.

[0059] A further aspect of the present disclosure relates to a brewing unit, in particular as described above, of a beverage preparation machine having a brewing chamber and a brewing chamber surface. The brewing chamber is substantially rotationally symmetrical with respect to an axis directed from a first brewing chamber half to a second brewing chamber half. The brewing chamber has a maximum axial extent in the direction of the axis, which is smaller than the largest diameter of the brewing chamber transverse to the axis. In this case, the brewing chamber has a thickness in the region of the axis which is equal to or less than the axial extent.

[0060] Such a shape of the brewing chamber has proven to be advantageous for the uniform extraction of a beverage substance.

[0061] Here and in the following, the brewing chamber surface is understood to mean the outer surface of the space enclosed by the brewing chamber, whereby recesses for penetrating agents for piercing the capsule or small depressions or grooves with a width of up to 3 mm are hidden.

[0062] The brewing chamber can have a reduced thickness on both sides in the area of ​​the axis. This reduced thickness on both sides further improves the extraction quality.

[0063] A brewing unit of a beverage preparation machine disclosed here, comprising a brewing chamber and a brewing chamber surface, in particular as described above, is configured to be substantially rotationally symmetrical with respect to an axis extending from a first brewing chamber half to a second brewing chamber half. The brewing chamber surface has a concave recess on at least one side, preferably on both sides, in the region of the axis and is convex in the region transverse to the axis.

[0064] The concave-convex design of the brewing chamber ensures optimal extraction of a correspondingly shaped capsule.

[0065] The brewing chamber surface can have a continuous curvature. Avoiding abrupt changes in direction and edges ensures a consistent extraction. Furthermore, a capsule held in the brewing chamber can be safely deformed and adapted to the shape of the brewing chamber.

[0066] The brewing chamber surface can have a minimum curvature radius of 3 mm. This again avoids abrupt changes in direction and edges.

[0067] Less than 50%, preferably less than 30%, particularly preferably less than 20%, of the brewing chamber surface can be designed as a flat surface. While such flat surfaces are conceivable, the aim is to achieve a surface that is as "round" as possible so that extraction can take place optimally. Of course, a "round" surface can also be achieved from a large number of polygons. In this case, however, a minimum angle of 150°, preferably 160°, particularly preferably 170°, must be maintained between two touching polygon surfaces.

[0068] The brewing unit can have two corresponding brewing chamber halves, which are arranged to be movable relative to one another in order to be moved from an open position for dispensing and inserting a capsule into a closed position for forming the brewing chamber and for enclosing and extracting the capsule. Both the first and the second brewing chamber can be arranged to be movable. It is also conceivable for both brewing chamber halves to be arranged to be movable.

[0069] The brewing chamber can have a maximum axial dimension in the direction of the axis in the range between 15 mm and 42 mm, preferably between 18 mm and 32 mm, particularly preferably between 20 mm and 26 mm. Typically, the maximum dimension is 22 mm.

[0070] The brewing chamber can have a largest diameter transverse to the axis in the range between 25 mm and 65 mm, preferably between 28 mm and 50 mm, particularly preferably between 30 mm and 35 mm. Typically, the largest diameter is 32 mm.

[0071] The brewing chamber can have a reduced thickness in the region of the axis in the range between 12 mm and 40 mm, preferably between 14 mm and 32 mm, particularly preferably between 15 mm and 20 mm. Typically, the reduced thickness is 17 mm.

[0072] These dimensions may vary. However, it has been shown that for optimal extraction, the axial dimension should be smaller than the largest diameter and the thickness should be smaller than the axial dimension.

[0073] Another aspect of the present disclosure relates to a beverage preparation machine with a brewing unit as described above. Another aspect of the present disclosure relates to a beverage preparation system comprising a capsule and a brewing unit as described above.

[0074] The disclosed invention is explained in more detail below with reference to figures which merely represent exemplary embodiments. They show:

[0075] Figure 1: a perspective view of a brewing unit with a closed brewing chamber from above,

[0076] Figure 2: a section through the brewing unit according to Figure 1,

[0077] Figure 3: a perspective view of a brewing unit with an open brewing chamber from above,

[0078] Figure 4: a section through the brewing chamber according to Figure 3,

[0079] Figure 5: a schematic representation of a capsule in an intermediate position,

[0080] Figure 6: the brewing unit of Figure 4 in a longitudinal section, with the brewing chamber no longer completely open,

[0081] Figure 7: the brewing unit of Figure 4 in a longitudinal section, with the brewing chamber closed,

[0082] Figure 8: a perspective view of a brewing chamber half with ejector and perforation means,

[0083] Figure 9: a representation of the hydraulic diagram of the brewing unit, Figure 10: a section through the closed brewing chamber of the brewing unit.

[0084] Figure 1 shows a perspective view of an embodiment of a brewing unit 3 for a beverage preparation machine, wherein the brewing chamber of the brewing unit 3 is closed. Visible on the top of the brewing unit 3 is a drop-in chute 40, which is delimited on both sides by a retaining means 38. A capsule 60 (see Figure 3) can be inserted into this drop-in chute 40 when the brewing chamber is open.

[0085] Figure 2 shows the brewing unit 3 from Figure 1 in a longitudinal section. The insertion chute 40 and a retaining means 38, which laterally delimits the insertion chute 40, are also visible. A brewing chamber 10, which is closed in the illustration shown, is arranged beneath the insertion chute 40. The brewing chamber 10 comprises a first brewing chamber 11 and a second brewing chamber half 12, which are movable relative to one another from an open position, in which the capsule 60 (see Figure 3) can be inserted between the brewing chamber halves 11 and 12, to the closed position shown. It is irrelevant which of the two brewing chamber halves 11, 12 is moving. Likewise, both brewing chamber halves 11, 12 can be movable. The movement of the brewing chamber halves 11, 12 relative to each other defines an axis 16 which is directed from the first brewing chamber 11 to the second brewing chamber 12.

[0086] The brewing chamber 10 has an inlet 23 in the first brewing chamber half 11 in order to be able to introduce an extraction liquid into the brewing chamber 10 and into the capsule 60 (see Figure 3).

[0087] The inlet 23 opens into the tips of individual perforation means 32a of an injector plate 58. Furthermore, the brewing chamber 10 has an outlet 24 in the second brewing chamber half 12 in order to be able to discharge a prepared beverage from the brewing chamber 10. The outlet 24 is formed in the second brewing chamber half 12 by openings to the hollow perforation means 32b. A further access 25 opens into the brewing chamber 10, through which a rinsing liquid can be introduced into the brewing chamber 10 and discharged therefrom again. This further access 25 is formed between the ejector 30 and the fixed part of the second brewing chamber half 12 as an annular gap 27 (see Figure 8). The annular gap 27 is dimensioned such that it serves as a filter element 26 (see Figure 8) to prevent residues from being flushed out of the brewing chamber 10 through the further access 25. The annular gap has a width of 200 pm.A sealing element 22 is arranged between the two brewing chamber halves 11 and 12, which promotes a tight closure of the brewing chamber 10.

[0088] Figures 3 and 4 show the brewing unit 3 with the brewing chamber 10 in the open position, wherein a spherical capsule 60 is held in an intermediate position between the brewing chamber halves 11 and 12 by the holding means 38.

[0089] Figure 5 shows a schematic view of the two holding means 38 which hold the capsule 60. In the intermediate position, the capsule 60 has no contact with the brewing chamber halves 11 and 12 but, apart from the holding means 38, lies freely in this intermediate position. The holding means 38 are spoon-shaped and enclose the capsule 60 in an angular range of 28° each. Accordingly, the smallest distance 39 between the holding means 38 is 16% smaller than the capsule diameter 61. Thus, the capsule 60 cannot slip through between the holding means 38. When the brewing chamber 10 is open, the holding means 38 are prestressed relative to one another by at least one spring element 41, as can be seen schematically in Figure 5.

[0090] As soon as the brewing chamber halves 11 and 12 move relative to one another and are only at a distance from one another which is less than the dimensions of the capsule 60, in the present case of a spherical capsule therefore less than its diameter 61 (see Figure 5), the holding means 38 are moved apart relative to one another against the spring force of the spring element 41, so that the capsule 60 is dropped. This movement apart of the holding means 38 is brought about by a control means 44 (see Figure 1), which slides in a wedge shape between the holding means 38 and thus increases their distance. The holding means 38 can additionally pivot about an axis 42, which is shown in Figures 3 and 4. The spring element 41 is preferably also arranged on this axis 42, so that the spring force acts along this axis 42.Due to the pivoting movement, the holding means 38 are completely removed from the area between the brewing chamber halves 11, 12. The brewing chamber halves 11 and 12 moving together are accordingly not hindered by the holding means 38. At the same time, the brewing chamber halves 11 and 12 catch the capsule 60 (see Figure 6) and align it so that it lies between the two brewing chamber halves 11 and 12 when the brewing chamber 10 is closed (see Figure 7).

[0091] During the movement of the brewing chamber halves 11 and 12 together, the injector plate 58 in the first brewing chamber half 11 is set back so that the capsule 60 has sufficient clearance between the brewing chamber halves 11 and 12. The perforation means 32b of the second brewing chamber half 12 are covered by the protruding ejector 30 so that the capsule 60 is not hindered in its movement by them. As can be seen in Figure 7, when the brewing chamber 10 is closed, the ejector 30 of the second brewing chamber half 12 is retracted again so that the perforation means 32b protrude from the ejector 30 and touch the capsule 60. The injector plate 58 of the first brewing chamber half 11 is still set back, the corresponding piercing pins of the injector plate 58 merely touch the capsule 60.

[0092] Figure 8 shows an enlarged view of the second brewing chamber half 12 with the circumferential sealing element 22. The ejector 30, which is movably mounted in the brewing chamber half 12, is clearly visible. The perforation means 32b, which protrude from the ejector 30, can also be seen. The perforation means 32b are designed as a hollow cannula and have inlet openings which form the outlet 24 of the brewing chamber. Between the ejector 30 and the second brewing chamber half 12, an annular gap 27 is formed which runs all around the ejector 30. This annular gap 27 forms, on the one hand, the further access 25 to the brewing chamber in order to be able to supply it with a rinsing liquid. By suitably dimensioning the gap 27, it also serves as a filter element 26 to prevent the unintentional introduction of foreign bodies into the brewing chamber and the flushing out of residual substances from the brewing chamber.In the embodiment shown, the annular gap 27 has a width of 200 pm.

[0093] Figure 9 shows a representation of the hydraulic diagram of a beverage preparation machine 1 with a brewing unit 3 as described above. In addition to the brewing unit 3, the beverage preparation machine 1 also has a tank 8 or a fresh water connection. From this tank 8 or fresh water connection, both the extraction liquid and the rinsing liquid are provided. A pump 4 serves to convey the extraction liquid and the rinsing liquid. A heating element 9 heats the water to the temperature required for the extraction of the desired beverage.

[0094] A first fluid line 49 leads from the pump 4 or the heating element 9 to the inlet 23 of the brewing chamber 10. A first valve 50 is arranged between the pump 4 and the inlet 23. This valve 50 is designed as a pressure valve and ensures that the extraction liquid can only pass through the first valve 50 after a preset pressure has been exceeded. It is also ensured that a hydraulic pressure piston 57 (see Figure 2) with its effective diameter generates a sufficiently large force so that the hydraulic pressure piston 57 can move. This pressure valve also prevents liquid from the brewing chamber 10 from flowing back into the heating element 9 or the pump 4.

[0095] A second fluid line 51 leads from the pump 4 or the heating element 9 to the further inlet 25 of the brewing chamber. A second valve 52 is arranged between the pump 4 and the further inlet 25. Through this second valve 52, the further inlet 25 and the brewing chamber 10 can be provided with a rinsing liquid, for example to wet a capsule 60 inserted in the brewing chamber (see Figure 7). At the same time, the second valve 52 ensures that no rinsing liquid can flow back into the heating element 9 or the pump 4 when the pump 4 is switched off.

[0096] A third fluid line 53 connects the further access 25 of the brewing chamber 10 to a collecting container 6. The third fluid line has a third valve. This ensures that the rinsing liquid is first fed into the brewing chamber 10 before being expelled into the collecting container 6 after the second valve 52 is closed and the third valve 54 is opened.

[0097] Starting from the outlet 24 (see Figure 8), a further fluid line leads as a beverage outlet 55 to a dispensing opening 7 of the beverage preparation machine. In the embodiment shown, a fourth valve 56, which in turn is designed as a pressure valve, is arranged in this beverage outlet 55. The fourth valve prevents the rinsing liquid, which is supplied under pressure to the brewing chamber 10, from flowing through the beverage outlet into a cup 2 for holding a beverage desired by a user. Since, in addition to the capsule 60, a certain volume of ambient air is also enclosed in the closed brewing chamber 10 before rinsing, the fourth valve 56 enables compression of this air volume and thus improved wetting of the capsule 60.In addition, this fourth valve 56 can ensure that the preparation of the beverage only takes place when a preset pressure is reached, which contributes significantly to the quality, especially when preparing coffee.

[0098] The beverage preparation machine 1 also has a controller 5, which controls the pump 4, the heating element 9, and the second and third valves 52, 54. Of course, the controller 5 can also be connected to sensors, such as a flow meter, a temperature sensor, etc., whose signals contribute to the control. For example, the movement of the brewing chamber halves 11, 12 can also be monitored by the controller 5 or even triggered by suitable drives.

[0099] To prepare a beverage, the brewing chamber 10 is closed after the capsule 60 has been inserted into the insertion shaft 40. This occurs by a relative movement of the two brewing chamber halves 11 and 12. In the embodiment shown, the first brewing chamber half 11 moves from the open position, as shown in Figures 3 and 4, via the half-open or half-closed position according to Figure 6 into the closed position according to Figure 7. The capsule 60 is first held by the two holding means 38 in the intermediate position between the two spaced-apart brewing chamber halves 11 and 12 on the axis 16, directed from the first to the second brewing chamber half 11 and 12. As soon as the brewing chamber halves 11 and 12 approach each other, the two holding means 38 are pushed apart by the control means 44 against the spring force of the spring element 41.The capsule 60 falls onto a lower edge of the brewing chamber halves 11 and 12 which have already been moved together somewhat. As the brewing chamber halves 11 and 12 are moved together further, the capsule is again aligned with the axis 16. The brewing chamber 3 can now be closed. The two brewing chamber halves 11 and 12 form a closed and tight brewing chamber 3 with the aid of the sealing element 22. In the first brewing chamber half 11, the injector plate 58 with its perforation means 32a is set back far enough that it only touches the capsule 60 but does not yet pierce it. In the second brewing chamber half 12, the ejector 30 is in a retracted position and releases the perforation means 32b. On this side too, the capsule 60 is only touched by the perforation means 32b, but is not yet perforated.

[0100] The control unit 5 switches on the heating element 9, opens the second valve 52 and releases the pump 4 to deliver approximately 10 ml of water. Since the first valve 50 only opens at a preset pressure, the water can only flow through the open second fluid line 51 to the further access 25 and into the brewing chamber 3. The water rinses the brewing chamber 3 and the capsule 60 enclosed therein is wetted. The second valve 52 is closed and the third valve 54 is opened. This opens the third fluid line 53. The rinsing water can escape from the brewing chamber 3 again. Since, in addition to the capsule, a certain volume of compressed air is also enclosed in the brewing chamber 3, the escape of the rinsing water is encouraged. After approx. After 1 s the third valve 54 is closed again, thus closing access to the collecting container 6.The second valve 52 is opened again to inject a further amount of rinsing water into the brewing chamber 3. The brewing chamber 3 is flooded again, and the capsule 60 is wetted again. After an exposure time of approximately 2 seconds, the second valve 52 closes, and shortly thereafter, the third valve 54 opens. Part of the rinsing water can again be drained into the collecting container 6.

[0101] The pump is activated when the second valve 52 is closed and delivers water. This water can only spread in the first fluid line 49 as far as the first valve 50. The water flows into an anteroom 59 of a hydraulic pressure piston 57, which is connected to the injector plate 58. The hydraulic pressure piston 57 is part of the first brewing chamber half 11. Since the first valve only opens above a preset pressure, in the illustrated embodiment above 7 bar, the water delivered by the pump 4 will first drive the pressure piston 57 and thus the injector plate 58. However, this reduces the volume of the brewing chamber 3, the capsule 60 is deformed and pierced by the perforation means 32a and 32b of the first and second brewing chamber halves 11 and 12. This deformation of the capsule 60 is particularly important when the capsule 60 comprises a pellet as a beverage substance.The deformation not only deforms the pressed tablet but also breaks it open. The beverage substance can therefore be extracted evenly. If the capsule contains a loose beverage substance, the capsule is also deformed by the injector plate. This compresses the loose beverage substance. As the capsule 60 was moistened with the preferably hot rinsing water before it was deformed, the capsule shell has softened and can undergo the deformation without any problems. The capsule 60 adapts its shape to the shape of the brewing chamber 3 as a result of the hydraulic pressing and expanding by the injected extraction liquid. As until the capsule 60 is completely deformed, i.e. Until the capsule shape is adapted to the shape of the brewing chamber 3, the third valve 54 is still open, the rinsing water is displaced from the brewing chamber 3 and fed to the collecting container 6 through the further access 25 and the third fluid line 53.

[0102] The pump 4 continues to pump water, even when the capsule 60 is completely deformed and the hydraulic pressure piston 57 has reached its end position. The pressure in the pre-chamber 59 increases further as a result. As soon as the preset pressure, 7 bar in the illustrated embodiment, is reached, the first valve 50 opens and the first fluid line 49 is released up to the inlet 23. The perforation means 32a of the injector plate 30 have already been pierced into the capsule 60 so that the water or extraction fluid is injected into the capsule 60 under high pressure. The extraction fluid penetrates the capsule 60, fills it and inflates it until the capsule 60 fills the brewing chamber 3. The pressure in the capsule 60 increases until the fourth valve 56 in the beverage outlet 55 opens. At this moment at the latest, the third valve 54 is closed.The extraction liquid penetrates the capsule 60 from its inlet side to the opposite outlet side, where it exits the brewing chamber as a prepared beverage through the outlet in the perforation means 32b. The beverage flows through the beverage outlet 55 to the dispensing opening 7, where it is dispensed into the cup 2. The fourth valve 56 opens only when a preset pressure is reached, which leads to high-quality extraction, particularly when preparing coffee.

[0103] Once the amount of water required for the desired beverage has been pumped by the pump 4, it switches off. The heating power of the heating element 9 is also switched off. The third valve 54 is now opened first. Any pressure present in the third fluid line 53 from the further access 25 can be diverted into the collecting container 6. The second valve 52 is then opened. The pressure built up in the first fluid line 49, in particular in the hydraulic pressure piston 57, is thus diverted via the second valve 52 and the third valve 54 to the collecting container 6. Since the first valve 50 is designed as a pressure valve, it will close immediately after the excess pressure collapses. Accordingly, no residue can be washed from the brewing chamber 3 into the second and third valves 52 and 54.As soon as the pressure in the antechamber 59 of the hydraulic pressure piston 57 decreases and the brewing chamber 3 is opened, the latter moves back into its original position due to a return spring 46 and in doing so pulls the injector plate 58 with its perforation means 32a away from the capsule 60.

[0104] As soon as the pressure in the beverage preparation machine is released, the movement of the brewing chamber halves 11 and 12 can be released again. When the brewing chamber 3 is opened, which can be done automatically or manually, the first brewing chamber half 11 moves from the closed position to the open position. The deformed and extracted capsule remains stuck to the perforation means 32b of the second brewing chamber half 12. At the last moment of the opening movement, the ejector 30 is moved forward, i.e. in the direction of the first brewing chamber half 11, so that it strips the capsule 60 from the perforation means 32b. At the same time as the ejector 30, the holding means 38 also move downwards again, so that a capsule 60 adhering to the ejector 30 is stripped off.

[0105] Figure 10 shows a section through the closed brewing chamber 10 of the brewing unit 3 along the axis 16 from the first to the second brewing chamber half 11 and 12. The brewing chamber 3 has a brewing chamber surface 15 which, apart from the perforation means 32a and 32b and any groove, has no sharp edges or abrupt changes in direction. The brewing chamber surface 15 has a continuous curvature, with the minimum radius of curvature being 3 mm. In the illustrated embodiment, the brewing chamber surface 15 has no flat surfaces.

[0106] The brewing chamber 15 is essentially rotationally symmetrical with the axis 16 as the axis of symmetry. The diameter transverse to the axis 16 is 32 mm. The brewing chamber 3 has a maximum extension 17 of 21.3 mm in the axial direction. In a central area, i.e. in the area of ​​the axis 16, the brewing chamber 3 has a concave recess 20 so that the brewing chamber has a reduced thickness 19 of just 17 mm there. It has been shown that this shape of the brewing chamber 3 allows a pellet of a spherical capsule 60 to be optimally broken open and extracted.

Claims

36 Patent claims 1. Brewing unit (3) of a beverage preparation machine with a brewing chamber (10) and a brewing chamber surface (15) , wherein the brewing chamber (10) is substantially rotationally symmetric with respect to a direction from a first brewing chamber half (11) to a second brewing chamber half (12) axis (16) is formed, wherein the brewing chamber (10) has a maximum axial extent (17) in the direction of the axis (16) which is smaller than the largest diameter (18) transverse to the axis (16), characterized in that the brewing chamber (10) has a thickness (19) in the region of the axis (16) which is equal to or less than the axial extent (17).

2. Brewing unit (3) according to claim 1, wherein the brewing chamber (10) has a reduced thickness (19) on both sides in the area of ​​the axis (16).

3. Brewing unit (3) of a beverage preparation machine with a brewing chamber (10) and a brewing chamber surface (15), in particular according to claim 1 or 2, wherein the brewing chamber (10) is essentially rotationally symmetrical with respect to an axis (16) directed from a first brewing chamber half (11) to a second brewing chamber half (12), wherein the brewing chamber surface (15) has at least on one, preferably on both sides, a concave recess (20) in the region of the axis (16) and is convex in the region transverse to the axis (16).

4. Brewing unit (3) according to one of the preceding claims, wherein the brewing chamber surface (15) has a continuous curvature. 37 Brewing unit (3) according to one of the preceding claims, wherein the brewing chamber surface (15) has a minimum radius of curvature of 3 mm. Brewing unit (3) according to one of the preceding claims, wherein less than 50%, preferably less than 30%, particularly preferably less than 20%, of the brewing chamber surface (15) is formed as a flat surface. Brewing unit (3) according to one of the preceding claims, wherein the brewing unit (3) has two corresponding brewing chamber halves (11, 12) which are arranged to be movable relative to each other in order to be moved from an open position for ejecting and inserting a capsule (60) to a closed position for forming the brewing chamber (10) and for enclosing and extracting the capsule (60). Beverage preparation machine (1) with a brewing unit (3) according to one of the preceding claims. A beverage preparation system comprising a capsule (60) and a brewing unit (3) according to any one of claims 1 to 7.