Brewing unit

Abstract

A brewing unit (10) for preparing beverages from a powdered product (P) containing at least one ingredient includes a support structure (20) having an internal cavity (16), and a dispensing assembly. The dispensing assembly includes a first assembly part (12) configured as a drawer having a receptacle (13) adapted to receive the powdered product, and a second assembly part (14) mounted for vertical sliding movement between raised and lowered positions within the upper part of the cavity. A filtering element (123) is mounted for vertical translation within the first assembly part, through which a discharge duct (124) is formed, the filtering element defining the receptacle (13) and the bottom surface of the brewing chamber. A brewing head (145) is carried by the lower end of the second assembly part (14), and the brewing head defines the top surface of the brewing chamber.

Description

Technical Field

[0001] The present invention relates to a brewing unit (coffee brewing unit) for a machine for preparing a beverage using a powder product containing one or more components, in particular coffee.

[0002] In the following description, for the sake of simplicity, reference is made to the use of compressed tablets, but the invention is not limited to a brewing unit operable with tablets, rather it is clearly more generally applicable to a brewing unit using capsules or alternatively pods, or bulk powder products.

Summary of the Invention

[0003] The object of the present invention is to provide an improved brewing unit.

[0004] This object and other objects are fully achieved according to the present invention by a brewing unit as defined in appended independent claim 1. The present invention further relates to a method for preparing a beverage as defined in appended independent claim 11.

[0005] Advantageous embodiments of the brewing unit according to the present invention are defined in the dependent claims, the content of which is to be understood as an integral part of the following description.

[0006] In short, the present invention provides a brewing unit for preparing a beverage from a powder product containing at least one component, a support structure having an internal cavity, and a dispensing assembly, - a first assembly part configured as a drawer insertable into or extractable from the lower part of the cavity and having a receptacle adapted to receive the powder product, and - A second assembly part vertically mounted so as to slide within the upper part of the cavity, the second assembly part being in an upper position allowing the insertion or extraction of the first assembly part, and between a lower position in which the second assembly part and the first assembly part are joined together to jointly define a brewing chamber, having a second assembly part, Within the first assembly part, filtering elements are mounted so as to translate in the vertical direction, and through these filtering elements a dispensing duct is obtained, The filtering elements define the bottom surface of the receptacle and the bottom surface of the brewing chamber, A brewing head suitable for injecting water into the brewing chamber is carried by the lower end of the second assembly part, The brewing head defines the upper surface of the brewing chamber and is provided with radial sealing means configured to contact the radial inner surface of the receptacle in the lower position of the second assembly part, relating to a brewing unit.

[0007] In the aforementioned unit, the brewing head and the filtering elements act as protection elements, preventing residues that may accumulate in the brewing chamber, especially when using compressed tablets or bulk powder products, from entering the water flow lines of the first and second assembly parts respectively.

[0008] Further features and advantages of the present invention are revealed by the following detailed description given purely by way of non - limiting example with reference to the accompanying drawings.

Brief Description of the Drawings

[0009]

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DETAILED DESCRIPTION OF THE INVENTION

[0010] Referring to FIG. 1, the overall brewing unit for a machine for preparing a beverage, particularly coffee, from one or more components, particularly a compressed tablet containing coffee powder, is indicated by the reference numeral 10.

[0011] As described above, the present invention has been described with respect to the use of components, or a compressed tablet containing a plurality of components, for the preparation of a beverage. However, the present invention is not limited to a brewing unit adapted for operation with tablets. Rather, it should be understood to include the case where, instead of a tablet, a powder contained in a capsule, pod, or other similar package suitable for brewing a beverage is provided. The present invention also includes the case of using bulk powder products. Therefore, for the purposes of the present invention, the term "powder product" covers both bulk powder products and powder products packaged in the form of capsules or pods or compressed in the form of tablets.

[0012] Referring to FIGS. 5 to 15, the brewing unit 10 basically includes a dispensing assembly including a first assembly part 12 made as a drawer and a second movable assembly part 14, and a support structure 20 that supports the first assembly part 12 and the second assembly part 14 and defines an internal cavity 16. An insertion port 16a formed in the front wall of the support structure 20 provides access to the cavity 16.

[0013] The first assembly part 12 is insertable into or extractable from the lower part of the cavity 16 and has a receptacle 13 adapted to receive a powder product P represented as a compressed tablet in the illustrated example. FIGS. 2, 6, and 11 show the state where the first assembly part 12 is completely extracted from the cavity 16. In this state, the first assembly part 12 is released from the support structure 20 and can be used to insert the powder product P into the receptacle 13 or for cleaning operations. FIGS. 8-9 and FIGS. 14-15 show the state where the first assembly part 12 is in the insertion end position. FIGS. 3, 7, and FIGS. 12-13 show the intermediate position of the first assembly part 12.

[0014] The second assembly part 14 is mounted to slide vertically within the upper part of the cavity 16 between the raised end position depicted in FIGS. 5-8 and 10-14 and the lowered end position depicted in FIGS. 9 and 15. In the raised end position, the second assembly part 14 enables the insertion of the first assembly part 12 into or extraction from the internal cavity 16. In the lowered end position, the second assembly part 14 and the first assembly part 12 are coupled to each other to jointly define a brewing chamber.

[0015] In addition to being adapted to receive the powder product P, the receptacle 13 is adapted to form a brewing chamber together with the second assembly part 14.

[0016] As described above, the first assembly part 12 is made as a drawer and has a main part 121 made as a sleeve and a handle 122 connected to the main part 121 to enable the operation of the first assembly part 12. A receptacle 13 is obtained at the upper end of the main part 121. The lateral sides of the main part 121 of the first assembly part 12 are adapted to be coupled to respective main guides 201 formed on the opposite lateral sides of the support structure 20 so that the first assembly part 12 can slide with respect to the support structure 20, thus enabling the insertion / extraction of the first assembly part 12.

[0017] Inside the first assembly part 12, more specifically inside its main part 121, a filtering element 123 is mounted so as to translate vertically through it in which a central discharge duct 124 for discharging the beverage is formed. In particular, the filtering element 123 is slidable between the raised end position depicted in FIGS. 6 - 7 and 11 - 12 and the lowered end position depicted in FIGS. 9 and 15, at which positions the filtering element abuts against a shoulder 121a formed in the main part 121 of the first assembly part 12.

[0018] The filtering element has a body 123a and a filtering screen 123b attached to the body 123a. The filtering screen 123b is fixed, for example, to a spindle pin 123c extending from the body 123a using, for example, a heat lock. Advantageously, this arrangement provides a planar surface that reduces possible dust accumulation. The filtering element 123, more specifically the filtering screen 123b, defines the bottom surface of the receptacle 13 and thus also defines the bottom surface of the brewing chamber when the first assembly part 12 and the second assembly part 14 are coupled to each other. Thus, the filtering element 123 provides a support surface for the powdered product P disposed within the receptacle 13.

[0019] Disposed around the filtering element 123 is a peripheral gasket 125 configured to exert a seal against the radially inner surface of the receptacle 13. Advantageously, when the filtering element 123 slides within the receptacle 13 from a lowered position to a raised end position, the peripheral gasket 125 can scrape clean the radially inner surface of the receptacle 13 from residual powder, particularly when the powder product P is in the form of bulk powder or compressed tablets.

[0020] As can be seen particularly in FIGS. 12 to 15, the filtering element 123 is associated with a drive element 126, which is mounted to translate vertically within the first assembly part 12, and more specifically within the main part 121 of the first assembly part 12. In particular, the filtering element 123 is connected to the drive element 126 via elastic means 127, particularly a coil spring. There is a coupling between the filtering element 123 and the drive element 126 that allows for relative sliding therebetween, restricted within a small stroke allowed by the deformation of the elastic means 127.

[0021] A central dispensing duct 128 is formed through the drive element 126, and this central dispensing duct 128 is fluidly connected to the central dispensing duct 124 of the filtering element 123 via a pre-brewing valve 129 interposed between the filtering element 123 and the drive element 126. The pre-brewing valve 129 consists of a valve member that cooperates with a seat formed in the dispensing duct 124 of the filtering element 123, and an elastic means, particularly a spring, is associated with this seat. The purpose of this valve is explained below.

[0022] On the opposite side of the lower end of the drive element 126, respective pins integral with the drive element 126 are disposed, one of which is visible in FIG. 2 and is denoted 131. The pin 131 is adapted to engage respective secondary guides 203 formed in the opposing side walls of the support structure.

[0023] As shown in FIGS. 10 to 15, unlike the horizontally oriented primary guide 201 that guides the sliding of the first assembly part 12 into the cavity 16 of the support structure 20, the secondary guide 203 is inclined downward. Such an arrangement ensures that during the sliding of the first assembly part 12 within the cavity 16, the drive element 126 is guided to translate perpendicularly with respect to the first assembly part 12 by the connection between the pin 131 and the secondary guide 203, and thereby drives the powder product P that may be disposed in the filtering element 123 and the receptacle 13 along with it.

[0024] Associated with the second assembly part 14 is a hydraulic cylinder 141, in which a plunger 143 that slides vertically is mounted. The plunger 143 is part of the second assembly part 14. Although an inlet 141a is shown in FIGS. 1 - 4, this inlet 141 can be supplied with liquid, particularly water, through a duct (not shown) to control the forward movement of the plunger 143 from its retracted position shown in FIGS. 5 - 8 and FIGS. 10 - 14 at the raised end position of the second assembly part 14. The forward movement of the plunger 143 is counteracted by elastic means 144, which particularly consists of a coil spring and is interposed between the plunger 143 and the hydraulic cylinder 141. Thus, such elastic means 144 is arranged to bias the plunger 143 towards its retracted position.

[0025] A central duct 143a is formed through the plunger 143, and this duct is connected to a water supply duct 146 obtained through the hydraulic cylinder 141. A flange 143b is obtained at the lower end of the plunger 143.

[0026] At the lower end of the plunger 143, a brewing head 145 integrated with the plunger 143 is arranged, which forms a part of the second assembly portion 14. A duct for injecting water into the brewing chamber is obtained through the brewing head 125 and is fluidly connected to the central duct 143a of the plunger 143.

[0027] As can be seen, for example, in FIGS. 9 and 15, the brewing head 145 has a main body 145a and an interface element 145b fixed to the main body 145a. The interface element 145b may be fixed to a spindle pin extending from the main body 145a, for example, and may be heat-locked. Advantageously, this arrangement provides a planar surface that reduces possible dust accumulation. The brewing head 145, more specifically the interface element 145b, defines the upper surface of the brewing chamber.

[0028] The interface element 145b is intended to come into contact with the powder product P. In the illustrated example, the interface element 145b is configured as a filter screen and will hereinafter be referred to as an inlet filter. When the brewing unit is intended to operate with a capsule, the interface element may be configured as an element with a tip for piercing the casing of the capsule.

[0029] Surrounding the brewing head 145 is a peripheral gasket 147 configured to contact the radial inner surface of the receptacle 13 in the lowered position of the second assembly part 14. Advantageously, when the powder product P consists of bulk powder or compressed tablets, the peripheral gasket 147 enables the radial inner surface of the receptacle 13 to be scraped clean of residual powder when the brewing head 145 slides within the receptacle 13.

[0030] Referring to FIGS. 1, 5 and 10, the brewing head 145 is integral with an intermediate member 150 removably attached to the lower end of the plunger 143. FIGS. 1, 5 and 10 accurately show the state where the intermediate member 150 is detached from the lower end of the plunger 143. In this state, the brewing head 145 can be cleaned. However, in other figures, the intermediate member 150 is in a state of being mounted on the lower end portion of the plunger 143.

[0031] The intermediate member 150 is configured as a drawer and has a main body frame portion 151 on which the brewing head 145 is mounted, and a handle 152 connected to the main body frame portion 151 and capable of operating the intermediate member 150.

[0032] The lateral sides of the main portion 151 of the intermediate member 150 are coupled to respective auxiliary guides 205 formed on the opposing lateral walls of the support structure 20, such that the intermediate member 150 can slide relative to the support structure 20 and is thus adapted to be inserted / withdrawn. Accordingly, the intermediate member 150 is selectively removable or attachable from the lower end of the plunger 143 along a slide direction parallel to the slide direction of the first assembly part 14.

[0033] In the main portion 151 of the intermediate member 150, a slit 153 is obtained that surrounds the upper end of the brewing head 145. The slit 153 is adapted to receive a flange 143b formed at the lower end of the plunger 143 when the intermediate member 150 is attached to the lower end of the plunger 143. To provide a seal between the brewing head 145 and the plunger 143, the upper portion 145c of the body 145b of the brewing head 145, which is intended to contact the lower end of the plunger 143, is made of an elastomeric material and is preferably molded. Advantageously, the portion 145c made of the elastomeric material materially connects the brewing head 145 to the main portion 151 of the intermediate member 150. There are teeth 154 formed on the intermediate member 150 and disposed within the slit 153 between the brewing head 145 and the handle 152 of the intermediate member 150. The teeth 154 are configured to elastically engage with a corresponding seat 143c formed at the lower end of the plunger 143. With such an arrangement, the intermediate member 150 can be snap - locked to the lower end portion of the plunger 143.

[0034] According to an alternative embodiment (not shown), the brewing head 145 may be a component removably attached to the plunger 123.

[0035] The brewing unit 10 may further comprise an optical sensor 40, only schematically shown in FIG. 12. This optical sensor 40 is arranged in a window 207 formed in the upper wall of the support structure 20. The optical sensor 40 is arranged such that when the first assembly part 12 passes through the insertion opening 16a and enters the cavity 16, the receptacle 13 faces it. At the detection position, inside the receptacle 13, and thus the tablet P therein, enters the field of view of the optical sensor 40. This optical sensor 40 is connected to a circuit 41 controlled by an electronic control unit ECU and, in cooperation therewith, provides a digital image of the tablet P. Thus, the electronic control unit ECU is programmed to perform the recognition of the product housed in the receptacle 13, for example, by reading an identification code or drawing affixed to the product, or other surface features of the product. The reading may be performed dynamically and thus may be performed with the first assembly part 12 detected without stopping at the detection position. In an alternative embodiment, the reading may be performed statically and the first assembly part 12 may be instantaneously stopped at the detection position.

[0036] If the recognition of the tablet is successful, the ECU is programmed to permit the advancement of the first assembly part 12 and to adjust the brewing parameters based on the recognized tablet. These parameters may be, for example, the amount of water injected into the brewing chamber.

[0037] To protect the optical sensor 40 from possible contamination by the powder product P, a movable closing element 45 is arranged at the window 207. This closing element 45 is normally in a closed position closing the window 207. An opening mechanism consisting of a lever 45a (visible, for example, in FIGS. 5 and 6) rotatable about a vertical axis is associated with this closing element 45. The lever 45a is integrally and rotatably connected to the closing element 45 via a shaft 45c. When entering the cavity 16, the first assembly part 12 engages the lever 45a and rotates it to open the window 207. During the extension while the first assembly part 12 slides within the cavity 16, the first assembly part 12 remains engaged with the lever 45a and can thus keep the window 207 open. When reaching a predetermined position within the cavity 16, the first assembly part 12 disengages from the lever 45a. Accordingly, the closing element 45 can return to its closed position biased by a coil spring 45d. The lever 45a is configured so as not to be engaged by the first assembly part 12 during extraction from the cavity 16, thereby preventing the opening of the window 207 and thus preventing steam from entering the reading area.

[0038] Next, an example of the operation of the brewing device 10 described above will be described in detail.

[0039] According to this embodiment, the working steps of the present machine can be defined as follows. 1. The first assembly part 12 having the tablet P in the receptacle 13 is inserted into the cavity 16. 2. Reading and recognition position of the tablet P. 3. The first assembly part 12 reaches the insertion end position. 4. The second assembly part 14 descends and the assembly closes. 5. Steps of pre-brewing, standby, and brewing of the tablet P. 6. The second assembly part 14 ascends and the assembly opens again. 7. The first assembly part 12 is removed. 8. The intermediate member is disassembled for cleaning.

[0040] During the introduction into the cavity 16, the first assembly part 12 reaches the reading and recognition position of the tablet P (step 2). By this step, the system can recognize the presence of the tablet P in the receptacle 13, recognize the type of the inserted tablet, and adapt the timing of compression and preparation before completing the closure of the preparation assembly.

[0041] During the insertion of the first assembly part 12, the filtering element 123 descends while preventing the tablet P from colliding with the intermediate member 150.

[0042] When reaching the end position of the insertion of the first assembly part 12, which can be detected by a sensor (not shown), the electronic control unit ECU controls the movement of the plunger 143 until the second assembly part 14 is coupled to the first assembly part 12. At this position, the brewing head 145 fits into the receptacle 13 until it contacts the tablet P. The movement of the plunger 143 continues until the filtering element 123 contacts the shoulder 121a formed on the main part 121 of the first assembly part 12 (compression of the tablet P), where the peripheral gasket 125 of the filtering element 123 also performs a front sealing function. Since the driving element 126 is vertically constrained by the secondary guide 203, the filtering element 123 moves relative to the driving element 126 against the action of the spring 127 interposed between the filtering element 123 and the driving element 126.

[0043] The displacement of the plunger 143 may be determined by the electronic control unit ECU as a function of the height of the tablet P, which may be determined using the optical sensor 40. More generally, it is possible to use powder products in different forms (compressed tablets, capsules, or simple bulk products) and in different doses for different preparations (espresso, lungo, double, filtered). The recognition system provided by the sensor 40 and the control unit ECU may be configured to set different extraction parameters according to the dose size and, in some cases, skip one or more steps in the extraction, as will be made clear below.

[0044] When the biasing position of the filtering element 123 with respect to the shoulder 121a is reached, the pressure in the hydraulic cylinder 141 is maintained.

[0045] The beverage is prepared in two different sub-steps: pre-brewing and waiting, and brewing of the tablet.

[0046] In the pre-brewing and waiting step, an initial small amount of hot water is sent into the brewing chamber through the central duct 143a of the plunger 143. It is an amount that cannot open the pre-brewing valve 129. This injection of a small amount of hot water and the subsequent waiting serve to wet the tablet P and prepare it for the brewing step.

[0047] In the brewing step, a second amount of warm water, an amount that can open the pre-brewing valve 129, is sent to the tablet P. In this step, the amount of hot water is much larger than in the previous step and is used to discharge the correct amount of beverage according to the tablet inserted into the receptacle 13. The pressure exerted by the plunger 143 of the hydraulic cylinder 141 is maintained throughout the pre-brewing step and the brewing step.

[0048] To compress the used tablet and drain the remaining hot water therein, a compression step may be provided to close the introduction of hot water into the central dispensing duct and send cold water to the hydraulic cylinder 141.

[0049] Once the preparation of the beverage is complete, the used tablet P must be removed so that a new tablet can be inserted into the receptacle 13 for the next preparation.

[0050] For this purpose, the pressure is removed from the hydraulic cylinder 121, whereby the plunger 143 biased by the spring 144 rises. Due to such a rise, the filtering element 123 biased by the spring 127 returns to its raised position.

[0051] Thereafter, the first assembly part 12 is extracted by gripping it with the handle 122, enabling the removal of the used tablet P, the cleaning / sweeping of the receptacle 13 and the filtering element 123, and in some cases, the filtering element 123 can also be removed from above together with the driving element 126.

[0052] Advantageously, due to the interaction between the pin 131 of the driving element 126 and the secondary guide 203, the translation of the first assembly part 12 brings the previously compressed product P upward, releases it from the radial friction of the brewing chamber, and enables it to be discharged (by gravity) only by the inclination of the first assembly part 12.

[0053] Also, the intermediate member 150 may be gripped and removed with the handle 152 to enable the cleaning / sweeping of the filter head 145.

[0054] Depending on the type of powder product used, one or more of the above steps may not exist. In particular, in the case of filter preparations or soluble coffee, the compression and pre-brewing steps are skipped. In other cases, post-compacting may not be necessary. In this regard, the control unit ECU may be configured to selectively enable or disable one or more of the above steps based on the recognition of the product type performed after processing the digital image captured by the sensor 40.

[0055] Regarding the compression step, it is observed that the pre-brewing valve member 129 is configured to elastically bias against each sheet on the filtering element 123 only when the brewing head 145 presses the filtering element 123 containing the powder product against the shoulder 121a. In the absence of such a compression action, there is no engagement between the pre-brewing valve 129 and each sheet on the filtering element 123. This enables blending without performing the pre-brewing and compression steps without operating the pre-brewing valve 129 (for example, when using a filter preparation).

[0056] Figs. 16 to 23 are diagrams showing other embodiments of the present invention. This embodiment is similar to the one described above in both structure and operation. The same numerical references are assigned to the elements corresponding to those of the previous embodiment. These elements will not be described further.

[0057] Figures 16 and 19 show the state where the first assembly part 12 is completely taken out from the cavity 16. Figures 18 and 21 show the state where the first assembly part 12 is at the insertion end position. Figures 17, 20, 22, and 23 show the state where the first assembly part 12 is at the intermediate position, more precisely the detection position. For the sake of convenience, the optical sensor is only schematically shown in Figure 20, while the related movable closure element is not shown in Figures 16 - 23. However, this movable closure element is positioned in the window 207 in the same way as the closure element 45 in the previous embodiment. Also, in Figures 16 - 23, a part of the drive mechanism for the movable closure element is shown and is represented by the slider again denoted by the reference number 45a.

[0058] In the embodiment of Figures 16 - 23, the first assembly part 12 is composed of a partition 12a formed between the main part 121 and the handle 122 of the first assembly part 12 and extending upward from the first assembly part 12. A screen 16b is arranged at the insertion opening 16a of the support structure 20, and this screen is formed to partially surround the insertion opening 16a, particularly the upper part of the insertion opening 16a. Depending on the shape of the support structure 20, the screen 16b may not be necessary.

[0059] As seen in Figures 17, 20, 22, and 23, when the first assembly part 12 is at the detection position, the partition 12a closes the insertion opening 16a so as to prevent light from entering through this opening in the illustrated example with the cooperation of the screen 16b.

[0060] Such a closure interrupts the input of light that varies depending on the ambient conditions during acquisition, and as a result, controlled and reproducible illumination conditions are obtained, which may be provided by an illumination system (not shown) related to the optical sensor 40 and controllable to illuminate the interior of the cavity 16.

[0061] Of course, without detracting from the principles of the present invention, details of embodiments and structures may vary widely with respect to those illustrated and described by way of purely non-limiting examples without departing from the scope of the present invention as defined by the appended claims thereby.

Claims

1. A brewing unit (10) for preparing a beverage from a powder product (P) comprising at least one component, a support structure (20) having an internal cavity (16), and a dispensing assembly, said dispensing assembly comprising a first assembly part (12) configured as a drawer insertable into or extractable from the lower part of said cavity and having a receptacle (13) adapted to receive said powder product, and a second assembly part (14) mounted to slide vertically within the upper part of said cavity, said second assembly part (14) having a raised position enabling insertion or extraction of said first assembly part (12) and a lowered position in which said second assembly part (14) and said first assembly part (12) are joined together to form a brewing chamber between said second assembly part (14) and said first assembly part (12), a filtering element (123) mounted in said first assembly part for translational movement in a vertical direction, a dispensing duct (124) being formed through said filtering element, said filtering element defining the bottom surface of said receptacle (13) and the bottom surface of said brewing chamber, a brewing head (145) adapted to inject water into said brewing chamber being carried by the lower end of said second assembly part (14), said brewing head defining the upper surface of said brewing chamber and comprising radial sealing means (147) configured to contact the radial inner surface of said receptacle (13) in said lowered position of said second assembly part (14). A brewing unit, characterized in that.

2. The brewing unit according to claim 1, wherein said filtering element is elastically biased towards an elevated end position with respect to said first assembly part (12).

3. The filtering element is elastically connected to a drive element (126) translationally movable in a vertical direction within said first assembly part. The driving element is guided by the support structure so as to translate in a direction perpendicular to the first assembly part (12) during the sliding movement of the first assembly part (12) into the cavity (16), the brewing unit according to claim 2.

4. A preparation duct (128) is formed which is fluidly connected to the discharge duct (124) of the filtering element (123) via a pre-brewing valve (129) interposed between the filtering element (123) and the driving element (126) via the driving element (126). The brewing unit according to any one of claims 1 to 3, wherein when the brewing head (145) presses the filtering element (123) containing the powder product against a shoulder (121a) formed in the first assembly part (12), the pre-brewing valve (129) is configured to elastically abut against the filtering element (123).

5. The second assembly part (14) operates hydraulically and further comprises a plunger (143) slidable within the upper part of the cavity. The brewing unit according to any one of claims 1 to 4, wherein the plunger carries the brewing head (145).

6. It further comprises elastic means (144) interposed between the plunger (143) and a hydraulic cylinder (141) fixed to the support structure (20). The brewing unit according to claim 5, wherein the elastic means is adapted to bias the plunger (143) towards a storage position corresponding to the raised position of the second assembly part (14).

7. The brewing unit according to claim 6, wherein the brewing head is fixed to an intermediate member (150) removably attached to the lower end of the second assembly part (14).

8. The brewing unit according to claim 7, wherein the intermediate member is selectively removably attached to the lower end of the second assembly part (14) along a sliding direction parallel to the sliding direction of the first assembly part (12) towards the cavity (16).

9. It further comprises reading means (40, 41) adapted to provide a digital image of the powder product. The reading means has an optical sensor (40) facing the receptacle (13) at a detection position where the first assembly part (12) crosses the insertion opening (16a) of the cavity (16), the brewing unit according to any one of claims 6 to 8.

10. The brewing unit according to claim 9, wherein the optical sensor is capable of statically or dynamically detecting the powder product.

11. The brewing unit according to claim 9 or 10, further comprising an electronic control unit (ECU) configured to adjust brewing parameters based on the digital image of the powder product.

12. The brewing unit according to claim 11, wherein the electronic control unit (ECU) is configured to determine the dosage size of the powder product from the digital image and adjust the brewing parameters as a function of the dosage size.

13. The first assembly part (12) comprises a partition (12a) extending in a lateral direction with respect to the sliding direction of the first assembly part (12) towards the cavity (16), at the detection position, the partition closes the insertion opening (16a) to prevent the intrusion of light from the insertion opening (16a), and the brewing unit according to any one of claims 9 to 12 having an illumination system capable of controlling the reading means to illuminate the inside of the cavity (16).

14. A method for preparing a beverage from a powder product (P) containing at least one component, using the brewing unit according to any one of claims 9 to 13, a) While the first assembly part (12) is in the insertion end position, supplying cold water to the hydraulic cylinder (141) to advance the plunger (143) of the second assembly part (14) and coupling the second assembly part (14) to the first assembly part (12); b1) Supplying a first quantity of heated water into the brewing chamber to wet the powder product (P) via the plunger (143) and the brewing head (145); b2) Waiting for a predetermined time; c) supplying, via the plunger (143) and the brewing head (145), a second quantity of heated water, which is greater than the first quantity, to the brewing chamber to prepare a beverage; d) further supplying cold water to the hydraulic cylinder (141) to further advance the plunger (143) and compress the used powder product (P) against the second assembly part (14). **Claim 15** A method for preparing a beverage with a brewing unit according to claim 11 or 12, wherein the electronic control unit (ECU) is configured to selectively enable or disable at least one of steps b1, b2 and d based on the digital image of the powder product.

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