Pressure-sensitive tamper mat

Abstract

Test system (T) for measuring a pressure force applied to a portafilter (R) by means of a tamper (tamper force), wherein the test system extends in a longitudinal direction (X), a transverse direction (Y) orthogonal to the longitudinal direction (X) and a vertical direction (Z) orthogonal to both directions (X, Y), the test system comprising: a basic body (G), a support area (A) formed on the base body for the manual support of a portafilter (R), a pressure sensor unit (D) received by the base body (G), comprising at least one pressure sensor (P) and designed to detect the tamper force acting on the contact area and to output an associated signal; an output unit (M) arranged on the base body (G), which is designed to output the signal to a user or a data processing unit; characterized by the fact that the base body has, at least in the bearing area, the form of a flat, preferably flexible mat, wherein the extent of the bearing area (A) in the longitudinal direction (X) and / or in the transverse direction (Y) is at least five times, preferably ten times, its extent in the vertical direction (Z).

Description

[0001] When preparing espresso, heated water flows through ground coffee in a machine and collects it in a cup. Typically, the ground coffee is first placed in a portafilter with an open top, which holds the grounds during preparation. Before the portafilter is inserted into the machine for preparation, the grounds in the portafilter are usually manually pressed together ("tamped") using a pressure force, which will also be referred to as the tamper force. The tamper force (usually between 100 and 200 Newtons) determines how tightly the coffee grounds are compressed. The degree of compression, in turn, influences the quality of the espresso produced, as it determines how quickly or slowly the hot water flows through the compressed grounds. Too little tamper force leads to too fast a flow and an under-extracted, watery espresso.Conversely, excessive tamper force can significantly slow or even partially block the water flow, resulting in over-extracted, bitter coffee. The correct tamper force is therefore crucial for optimal extraction and a balanced flavor.

[0002] To control the tamper force, various solutions are known in the state of the art, albeit with their drawbacks. The tamper used to compress the coffee grounds consists, in its simplest form, of a tamper base, usually in the form of a flat metal cylinder, which is placed or pressed onto the grounds in the portafilter to compress them. A knob-like handle for operation usually protrudes upwards from the center of the top of the metal cylinder.

[0003] A known tamper design includes a preferably adjustable mechanical spring located in the handle of the tamper, which allows the tamper force to be regulated using the spring stiffness. However, this type of pressure or tamper force measurement / monitoring is inaccurate, as there is no display and the spring stiffness changes with frequent use. Furthermore, the spring must be oiled regularly for proper operation. However, the use of machine oil in food processing carries risks and is subject to strict regulations. For example, no oil may get into the coffee grounds when tamping.

[0004] Another known state-of-the-art machine is a fully automatic tamper machine that offers internal force control using a load cell for tamping. This machine handles the entire tamping process, but its size requires a lot of space. Furthermore, it is disproportionately expensive for a single-purpose tool. These machines are technically complex, making them prone to errors. Furthermore, they are often difficult to clean.

[0005] Also known in the state of the art is a so-called handheld tamper station. This is a device with an integrated force cell. These stations are usually made of metal or plastic and have a cuboid shape. The integrated force cell includes a holder for the portafilter and measures the tamper force with which the coffee grounds are pressed into the portafilter seated in the holder. The measured values ​​are then shown on a digital display, which also provides further instructions and additional information. The complex configuration of the tamper station with its display and various measuring and display functions makes the devices technically complex and disproportionately expensive.

[0006] In view of the described disadvantages of the prior art, it is the object of the present invention to provide a simple and space-saving device for measuring the tamper force when compressing the coffee powder in the portafilter, which is durable, low-maintenance, easy to clean and inexpensive to manufacture and is also aesthetically pleasing.

[0007] The object is achieved by a testing system according to claim 1. Further advantageous embodiments emerge from the subclaims.

[0008] According to the invention, the testing system comprises a flat base body which extends in a longitudinal direction X, a transverse direction Y orthogonal to the longitudinal direction X and a height direction Z orthogonal to both directions X, Y.

[0009] The base body comprises at least one support area for manually supporting at least one portafilter, which in turn is designed to hold the coffee grounds to be compressed. During tamping, the portafilter transfers the tamping force to the support area.

[0010] Furthermore, the testing system according to the invention comprises a pressure sensor unit which has at least one pressure sensor and is designed to detect the tamper force acting on the support area and to output an associated signal.

[0011] Furthermore, the test system according to the invention comprises an output unit which is designed to output the signal to a user or a data processing unit.

[0012] The testing system according to the invention is characterized in that the base body has the shape of a flat, preferably flexibly flexible mat, at least in the support area, wherein the extension of the support area in the longitudinal direction X and / or in the transverse direction Y is at least five times, preferably ten times, its extension in the vertical direction Z. Unlike the tamper devices known from the prior art, a flat pressure sensor according to the invention, in interaction with the flat support area, allows an essentially two-dimensional and therefore particularly simple construction and a comfortable and space-saving use of the testing system.

[0013] Preferably, not only the support area, but the entire base body, which determines the external dimensions of the test system, meets the aforementioned dimensional criteria and the properties of a flexible mat. The entire base body does not need to be significantly higher than the pressure sensor used and can therefore be very flat. The pressure sensor is preferably embedded in the base body, protected from moisture, or enclosed within it. The base body can be round or polygonal in a plane spanned by the longitudinal X and transverse Y directions.

[0014] According to an advantageous embodiment of the invention, the test system according to the invention comprises a water-repellent surface coating on the base body to repel liquids and protect against contamination. The surface coating can be made of silicone, rubber, or another water-repellent plastic. The surface coating is preferably non-slip to prevent the test system from slipping during use. Particularly preferably, the surface coating is flexible or elastic to accommodate deformation of the base body.

[0015] The surface coating should at least cover the contact area to repel any moisture that may accumulate there. The surface coating should preferably surround the base body on as many sides as possible to provide the best possible protection for the test system against moisture. This does not preclude any openings in the base body from being excluded or separately sealed with special plugs or covers. Such openings may be required, for example, for electrical connections (e.g., charging sockets, USB ports, battery compartments, etc.). Such a surface coating enables quick and uncomplicated cleaning of the system and simple and safe use. The surface coating also serves to protect electronic components within the base body of the test system.

[0016] The flexible property of the support area or the entire base body can be achieved, for example, by the housing also taking on the function of the surface coating and being made of rubber, latex or another suitable material which is, on the one hand, water-repellent and, on the other hand, as flexible as possible.

[0017] A flexible base body facilitates storage of the test system when not in use and protects it from damage caused by impact. Furthermore, its flexible and soft surface is resistant to hard or sharp objects and allows for the gentle or cushioned placement of the portafilter or other components. A coating that is as completely water-repellent as possible allows the test system to be cleaned by wiping it with a damp cloth or even holding it under a jet of water without damaging the other components located in the base body.

[0018] Some advantageous embodiments of the invention relate to the support area, which interacts with the portafilter used in each case. A portafilter known per se is essentially always constructed in the same way and comprises a handle and a largely cylindrical holding body with an internal, upwardly open cavity that holds the coffee grounds or a sieve, which in turn holds the coffee grounds. The portafilter often has small projections on its outer circumference to enable the portafilter to be secured in an espresso machine. Furthermore, a fork-like outlet spout is often provided at the lower end of the portafilter, through which the finished espresso can flow from the center of the cylinder downwards into at least one espresso cup. Due to this design of portafilters, which is widespread on the market, their controlled support on a preferably flat surface is only possible under certain conditions.In particular, it would be disadvantageous to introduce the tamper force into the support area via the outlet nozzle, as the tamper force would then only be transmitted via a relatively small and undefined contact surface at the lower end of the outlet nozzle, with a correspondingly high and undesirable point load. The testing system according to the invention takes this circumstance into account and facilitates the controlled support of known portafilters through a suitably designed support area and / or a specially designed pressure sensor (the support area is to be considered the zone of the base body in which a mechanical force applied to the base body from the outside, in particular the tamper force, can be detected by the pressure sensor of the testing system). Preferably, the dimensions of the support area are approximately comparable to those of the pressure sensor. Furthermore, the support area is preferably essentially flat.It is possible to design a support area with a surface area that exceeds the area of ​​the pressure sensor. For example, the support area can include a section on which the portafilter can be placed and the tamper force can be measured, and another section that serves as a storage area for, for example, the tamper or a grinder, etc.

[0019] The support area can be designed so that a portafilter can rest completely or partially on the support area along the circumference of its holding body. For this purpose, the support area can be designed in the shape of a circular arc, with the circular arc, for example, having an opening angle of 180° (semicircle) or more. The support area can also be designed as a completely closed ring (360°) or as a circular surface. Various variants are conceivable for controlling the positioning of the portafilter (especially a portafilter with a downwardly projecting spout) for tamping in such a support area.

[0020] To ensure that the outlet spout can protrude freely downwards, one embodiment of the testing system provides a portafilter holder whose underside can be placed onto the support area and whose upper side is designed to hold the portafilter. By selecting a suitable vertical height for the portafilter holder, the outlet spout can protrude freely downwards within the portafilter holder. The portafilter holder can, for example, have the shape of a hollow cylinder, the radii of which are preferably selected to match the circular support area. A portafilter inserted into this portafilter holder at the upper end then rests on the hollow cylinder preferably along its circumference or via support projections specially provided for this purpose in the hollow cylinder, while the central outlet spout can protrude freely downwards inside the hollow cylinder.The hollow cylinder then transfers the tamper force introduced into the portafilter downwards into the support surface or the pressure sensor located there.

[0021] Of course, instead of a cylindrical shape, any other shape of portafilter holder, especially one with a hollow profile, can be used, as long as it is suitable for holding the portafilter and for transferring the tamper force to the support area.

[0022] Preferably, the portafilter holder has an upwardly open recess or groove along its circumference or on the side, through which a portafilter handle, which usually protrudes laterally from the actual portafilter, can protrude without obstructing the peripheral support of the portafilter on the portafilter holder.

[0023] Preferably, the portafilter holder is a separate component of the testing system, meaning it can be freely placed on the support area as needed. As a separate component, the portafilter holder is particularly easy to clean, and the separate base body retains its flat design according to the invention. The portafilter holder can be made of plastic or metal, in particular.

[0024] The testing system can also include several different portafilter holders that are used for different portafilter sizes. For example, the portafilter holders could each have identical dimensions for resting on the support area, while the opposite upper section intended for the portafilter insert has a customized receiving contour suitable for the specific portafilter.

[0025] Another variant for accommodating a spout provides a support area (preferably again in the shape of a circular arc) with a central recess. The portafilter spout can protrude into or through this recess without interference, while the portafilter transmits the tamper force along its circumference into the support area in a controlled manner. To provide sufficient space for the spout, the test system in this case includes a small frame on which the base body is mounted. This creates a vertical distance between the base body and, for example, a tabletop on which the frame is positioned. This distance is sufficient to accommodate the portafilter spout without interference when the portafilter is placed on or in the support area.

[0026] The support area (with its central recess) can be designed in the form of a circular ring, completely enclosed within the surface of the base body, which enables a particularly uniform introduction of force into the correspondingly designed force sensor. However, it is also conceivable to form the support area on the edge of the base body, so that the portafilter does not rest on the base body along its entire circumference. For this purpose, the support area can, for example, be designed as a circular ring section with an opening angle of more or less than 180°, with the center of the circular ring lying outside, inside, or on the edge of the base body. A recess formed around the center of the circular ring within the support area again allows the outlet spout of the portafilter to pass through.

[0027] The pressure sensor can, for example, be designed as a sensor based on the capacitive measuring principle. A capacitive sensor operates on the basis of changes in the electric field, which in the case of the present invention are caused by the tamper force and the pressure exerted by it on the sensor. Such a sensor is particularly accurate and reliable and operates with consistent precision and reproducibility. The capacitive sensor can detect minimal pressure changes, enabling the barista to observe and monitor even small adjustments in the force applied. Furthermore, such a sensor is characterized by its particularly flat design, which facilitates its integration into the flat base body according to the invention.

[0028] The pressure sensor can comprise a sensor array. Such an array consists of several smaller capacitive sensors distributed across the contact area, allowing the tamper force to be measured simultaneously at different points within the contact area. This allows the force distribution across the entire portafilter to be recorded, allowing the tamper force to be applied evenly and in a controlled manner across the entire portafilter to the coffee grounds. By evaluating the individual sensor signals, the user can be informed in real time whether the force distribution is optimal or whether adjustments are necessary to ensure consistent extraction. The pressure sensor can also comprise a force sensing resistor (FSR) or a strain gauge.

[0029] The output unit serves to output signals generated in connection with the operation of the test system. A signal can be output, for example, acoustically and / or visually and / or haptically (for example, using a vibration element). Preferably, the signal is displayed via a display device or via one or more lighting devices. The visual output of the signal can comprise numerical values ​​or symbols or single- or multi-colored light signals. Alternatively or additionally, the signal can also be output acoustically, for example, via a loudspeaker or other acoustic means known to those skilled in the art.

[0030] The signal can, in particular, relate to a tamper force. For this purpose, the light source could comprise an LED strip that visualizes the applied force using different colors or light intensities, which is particularly intuitive and easy to understand. Preferably, different colors are assigned to corresponding tamper force values. For example, an insufficient tamper force could be indicated as yellow, an excessive tamper force as red, and an appropriate tamper force as green. A display could show numerical values ​​of the tamper force. Alternatively or additionally, it could also be configured to output symbols, other numerical values, text, operating instructions, or operating states.

[0031] However, signals that indicate certain other operating states are also conceivable, such as readiness for operation, an overload, an operating voltage that is too low, a successfully established or interrupted communication connection with an external device, etc.

[0032] The testing system can also be configured to specify one or more threshold values ​​for the tamper force, the operating voltage, or other operating parameters, so that a signal is output to the user when a threshold value is exceeded or undershot. An optical, haptic, or acoustic signal can also change gradually, for example, by increasing or decreasing its brightness, vibration intensity, or volume depending on an operating parameter, in particular the tamper force.

[0033] The testing system can also be configured to output various acoustic, visual, or haptic signals, either alternatively or in addition to one another, depending on predefined operating modes. For example, the user could select a specific operating mode depending on the type of coffee, with different threshold values ​​or display methods being specifiable depending on the type of coffee.

[0034] Alternatively or additionally, the output unit can also be configured to output a signal to an external device. For example, a signal can be output to an espresso machine or a mobile device, preferably via wireless signal transmission. Integration of the test system into a smart home architecture is also conceivable.

[0035] In the area of ​​the output unit integrated into the base body, the test system can have a greater vertical extension than, for example, in the support area. For example, a base body with one or more vertical steps is conceivable, the lowest step of which determines the essential extension of the base body and encompasses the support area, while components of the output unit or power supply, for example, are arranged in an adjacent and slightly thicker step. Unlike the flat pressure sensor, these components can require a somewhat larger vertical installation space, which explains the stepped design of the base body. A surface coating can nevertheless extend across all steps of the base body and protect it from moisture on all sides.

[0036] According to a preferred embodiment, the test system comprises a rechargeable battery for power supply, which can be charged via cable connection and / or via solar panel and / or inductively. For example, a USB port can be used as the charging interface. The power supply via a rechargeable battery enables the test system to be used wirelessly, which simplifies handling and enables use in different locations. A USB-C port is widely used and universally compatible, making the charging port particularly user-friendly. For increased autonomy and energy efficiency, the test system can also have an automatic shutdown function that puts the device into energy-saving mode when it is not used for a certain period of time. Alternatively or additionally, an integrated solar panel could extend the battery life or serve as the sole power supply.

[0037] According to a preferred embodiment, the test system comprises a data transmission unit that can be coupled to a higher-level control unit, preferably associated with an espresso machine, a mobile phone, or a smart home installation, for data transmission, preferably via Bluetooth or a Wi-Fi network. Data transmission can be used, for example, via an app on a mobile phone or an espresso machine. This allows the signals generated in the test system to be displayed or output on other components. Conversely, certain operating modes, threshold values, or other parameters could be transmitted from a higher-level control unit to the test system and preferably stored there.

[0038] In an application that interacts with the testing system, for example, on a mobile phone, users can view a history of recent measurements, access graphical representations of the force distribution, and receive recommendations for optimal settings. The app can also contain a database with various force profiles for different coffee varieties or grind sizes, which can be individually adjusted and saved. The app could also offer a training module that guides the user and provides feedback on the tamper force applied. By storing and analyzing the measurement data, the testing system can learn how the user tampes and make targeted suggestions for improvement to optimize the quality of the espresso in the long term.

[0039] According to a preferred embodiment, the pressure sensor unit is calibratable and / or includes a tare function. The tare function allows the scale to be zeroed to prevent, for example, the weight of the portafilter from being accidentally recorded. Calibration or the tare function allows the testing system to be used smoothly with different portafilters that differ in weight, for example.

[0040] According to a preferred embodiment, the pressure sensor unit can be used as a scale, which can preferably be used to determine the weight of a quantity of coffee powder in a portafilter. In this case, the pressure sensor unit can be tared with the empty portafilter already in place, in order to directly detect the weight of the coffee tester that is subsequently inserted into the portafilter.

[0041] The surface coating can be designed to provide the user with a pleasant grip and facilitate handling. Different degrees of material hardness could be available to meet the needs of users who prefer a softer or harder material. The combination of all these features creates a testing system that is not only functional but also aesthetically pleasing and easy to use. The direct integration of the measuring system into the tamper mat significantly simplifies cleaning and maintenance and ensures that the tamper force can be measured precisely and reproducibly at all times. The flexible force adjustment, the compact design, and the option of wireless operation make the testing system an ideal tool for both private and professional use.By using a capacitive sensor and integrating it into a familiar environment, the user is intuitively introduced to the application and can precisely control and adjust the tamper force to achieve the best possible extraction quality.

[0042] In summary, the invention offers an innovative, compact, and precise testing system for measuring tamper force during coffee preparation. The integration of all essential functions into a pressure-sensitive, flat tamper mat, the use of a preferably capacitive pressure sensor, and the possibility of app integration make the system extremely flexible and adaptable. The combination of ease of use, high measurement accuracy, and aesthetic design makes the testing system according to the invention a practical tool.

[0043] Many espresso machines come with simple mats for temporarily supporting portafilters, but these mats offer no additional technical functions. The inventive mat-shaped testing system can therefore be easily integrated into an espresso machine system without requiring additional equipment.

[0044] The pressure-sensitive tamper mat is designed to function as a fully integrated tamper force measurement system. The mat is flat and flexible, providing a stable and gentle rest for the portafilter. The height of the mat is deliberately kept low, making the testing system not only space-saving but also easy to use alongside an espresso machine. By integrating the measurement system directly into the mat, the appearance and handling of the mat remain largely unchanged, making it intuitive and familiar for the user. The low height and flexible design also allow for easy cleaning, which is particularly advantageous in professional environments where hygiene is paramount.

[0045] In the following, some embodiments of the invention will be explained in more detail using exemplary figures. Fig. 1 a first embodiment of the test system; Fig. 2 the embodiment from Fig. 1 in opaque representation; Fig. 3 an embodiment with a portafilter holder; Fig. 4 a close-up of the portafilter holder from a different angle; Fig. 5 another embodiment of the test system Fig. 6 another embodiment of the test system Character description:

[0046] Fig. 1 shows an exemplary embodiment of the testing system T according to the invention in a transparent oblique view. The testing system extends in a longitudinal direction X, a transverse direction Y orthogonal to the longitudinal direction X and a vertical direction Z orthogonal to both directions X and Y, as indicated in the coordinate system. The base body G in this exemplary embodiment is essentially divided into two regions which differ, among other things, in their extent in the vertical direction Z. The lower or flat region in this exemplary embodiment comprises the support region A and extends in the transverse direction Y across the entire width of the testing system. The flat region A extends in the longitudinal direction X up to a step S which explains the difference in the extent in the vertical direction Z between the two regions. In this exemplary embodiment, the support region A has a smaller extent in the vertical direction Z than the step S in which an output unit M is located.The step extends in the transverse direction Y across the entire width of the test system and in the longitudinal direction X over approximately one third of the test system. In this exemplary embodiment, a pressure sensor unit D essentially consists of a pressure sensor P and electronics E connected to the pressure sensor P. In this exemplary embodiment, the electronics E is located in the higher-stepped area of ​​the test system T. The pressure sensor P is arranged in the support area A and is connected to the electronics E. In this exemplary embodiment, the pressure sensor P is circular in shape, but can also be circular in shape. The pressure sensor P can measure the tamper force applied to a portafilter R. An output unit M is arranged in the higher or stepped area of ​​the exemplary embodiment. In this exemplary embodiment, the output unit M outputs the signal visually, using a light source in the form of a colored illuminated display.The light source can be an LED strip or any visual indicator, such as a series of differently colored LEDs or a display. The output unit M is connected to the electronics E of the pressure sensor unit D and is controlled by it.

[0047] The base body G has the shape of a flat, preferably flexibly flexible mat in the support area, whereby the extension of the support area A in the longitudinal direction X and in the transverse direction Y is at least five times its extension in the vertical direction Z. The flexural flexibility of the support area A is ensured by a water-repellent surface coating L and the flat design of the pressure sensor P. The water-repellent surface coating L is preferably made of rubber or silicone or any other flexibly flexible, water-repellent material. The surface coating L essentially surrounds the entire base body G with the exception of a recess for the lamp of the output unit M and any existing connections for a power supply (not shown).

[0048] A portafilter R (not shown) can be placed directly or indirectly in conjunction with a portafilter holder H on the support area A, preferably above the pressure sensor P. The tamper force acting on the portafilter, which is introduced into the portafilter R by the user while it is resting on the support area A, is measured by the pressure sensor unit D. A signal generated from the tamper force measured in this way is output by the pressure sensor unit D to the output unit M. The output unit M outputs the signal to the user via the light source. In this exemplary embodiment, different values ​​of the tamper force are each assigned a color range of the colored illuminated display. A weak tamper force, which is not optimal for espresso preparation, is assigned in this case a substantially yellow color range of the colored illuminated display. This means that the colored illuminated display lights up yellow if the tamper force is insufficient.When the tamper force is optimal, the colored indicator lights up green. If the tamper force is too strong, the colored indicator lights up red.

[0049] In one embodiment, the output unit M is designed as a luminous strip which extends, for example, along the transverse direction Y and which is distinguished in that it begins to glow from a first end depending on the load. For example, the luminous strip can be divided into different regions which are assigned different colors along the transverse direction Y. A first region arranged on the left could be yellow and glow yellow as long as an insufficient tamper force is applied. A second region of the luminous strip, adjacent to the first region, could be green. When an optimal tamper force is applied, the second green region can glow in addition to the first yellow region. A third region of the luminous strip, adjacent to the second green region, could be red.If the tamper force is too strong, the third red area may light up in addition to the first yellow and second green areas. The signal output from the output unit M informs the user whether the optimal tamper force is being applied.

[0050] Fig. 2 shows the inventive embodiment of the test system T from Fig. 1 in an opaque oblique view and in the previously described spatial orientation. The support area A has a slightly circular recess above the point where the pressure sensor P is located in the base body G. This recess signals to the user that the tamper force is optimally measured at this point in the support area A. The dispensing unit M terminates in the vertical direction Z with the surface coating L.

[0051] Fig. 3 shows an embodiment of the test system T, which in addition to the embodiment of Fig. 1 and Fig. 2 also comprises a portafilter holder H. The portafilter holder H is designed in a hollow cylinder shape and is detachably connected to the base body G of the testing system. It can, for example, be clamped or pushed into suitable holding means on the base body or rest freely on the base body G. The portafilter holder H has a recess on the upper circumference, which is designed such that the handle of a portafilter inserted into the portafilter holder H can protrude laterally through the recess from the hollow cylinder. This allows the portafilter to be fully inserted into the portafilter holder H and to introduce a tamper force largely evenly over the circumference of the portafilter into the portafilter holder H. The recess for the handle also prevents the portafilter from slipping while the tamper force is being applied. The hollow cylinder shape at the lower end of the portafilter holder H, which in Fig. 4, the tamper force is transferred evenly to the pressure sensor P via the annular support surface. On the support area A of the embodiment of the test system T, there is sufficient space next to the portafilter holder H to place or set down a tamper C, for example.

[0052] Fig. 4 shows the portafilter holder H from Fig. 3 from a different angle. Here, the ring-shaped support surface at the lower end of the portafilter holder H is visible. For clarity, the height direction Z is indicated.

[0053] Fig. 5 shows a further embodiment of the testing system T in an oblique view together with a tamper C and a portafilter R. In this embodiment, the base body G is designed such that a portafilter R can be received in a recess in the base body G. The base body G is arranged on a frame which extends as a hollow cuboid along the aforementioned spatial directions X, Y, Z and whose interior is freely accessible from the outside in the longitudinal direction X. The base body with its upward-facing support area A, the dispensing unit M (not shown) and the pressure sensor unit D is arranged on the upper side of the frame. The upper side of the frame and the support area A of the base body G have a circular cut-out-shaped recess which is designed such that a portafilter can be inserted into it, while a possibleThe outlet spout provided at the lower end of the portafilter can protrude freely downwards through the recess without obstructing the controlled and even resting of the portafilter on the support area. The pressure sensor P is designed in a circular arc around the recess and, like the recess, is positioned at the edge of the recess in the base body so that it can detect the tamper force acting on a portafilter inserted into the recess. The surface coating L can cover the entire base body G or just its upper side. The base body G can be permanently or detachably connected to the frame G.

[0054] Fig.6 shows another embodiment of the testing system T in an oblique view, along with a tamper C and a portafilter R. In this embodiment, a base body G is designed such that the testing system T can be placed against an edge, for example, a table edge or kitchen countertop edge. The pressure sensor P can be designed linearly along the edge of the support area A, as shown. The pressure sensor P is arranged such that the tamper force on a portafilter R, which is placed against the edge of the testing system T, can be measured. List of reference symbols A support area B Lamps C Tamper D Pressure sensor unit E Electronics G base body H Portafilter holder L Surface coating M output unit P pressure sensor R portafilter S level T test system X Longitudinal direction Y transverse direction Z Altitude direction

Claims

[1] Test system (T) for measuring a pressure force exerted by a tamper on a portafilter (R) (tamper force), the test system extending in a longitudinal direction (X), a transverse direction (Y) orthogonal to the longitudinal direction (X) and a height direction (Z) orthogonal to both directions (X, Y), the test system comprising: a base body (G), a support area (A) formed on the base body for manually supporting a portafilter (R), a pressure sensor unit (D) accommodated in the base body (G), which comprises at least one pressure sensor (P) and is designed to detect the tamper force acting on the support area and to output an associated signal; an output unit (M) arranged on the base body (G) which is designed to output the signal to a user or a data processing unit; characterized by , that the base body has the shape of a flat, preferably flexibly flexible mat at least in the support area, wherein the extension of the support area (A) in the longitudinal direction (X) and / or in the transverse direction (Y) is at least five times, preferably ten times, its extension in the height direction (Z). [2] Test system (T) according to one of the preceding claims, characterized by that the base body (G) has a water-repellent surface coating (L) which a) is essentially made of a rubber, silicone or other elastic material, and / or b) surrounds the base body on all sides, preferably watertight. [3] Test system (T) according to one of the preceding claims, wherein the pressure sensor (P) is annular or in the form of a circular arc, so that the portafilter (R) or a portafilter holder (H) receiving the portafilter introduces the tamper force along the annular shape or the circular arc into the pressure sensor (P). [4] Test system (T) according to one of the preceding claims, wherein the output unit (M) comprises: a) one or more illuminating means (B) for emitting optical signals, preferably in different colours and / or depending on the tamper force and / or in a linear arrangement in the manner of a luminous strip and / or b) a display for showing symbols, numerical values, text, operating instructions or operating states and / or c) Means for emitting acoustic signals, preferably depending on the tamper force. [5] Test system (T) according to one of the preceding claims, further comprising a portafilter holder (H) formed in the base body (G) or movable relative thereto for receiving a portafilter (R) in order to introduce the tamper force from a portafilter (R) via the portafilter holder (H) into the pressure sensor. [6] Test system (T) according to one of the preceding claims, further comprising an accumulator for power supply, which can be charged via cable connection and / or via solar panel and / or inductively. [7] Test system (T) according to one of the preceding claims, further comprising a data transmission unit which can be coupled for data transmission, preferably via Bluetooth coupling or WLAN network, to a higher-level control unit, preferably belonging to an espresso machine, a mobile phone or a smart home installation. [8] Test system (T) according to one of the preceding claims, wherein the pressure sensor unit is calibratable and / or offers a tare function. [9] Testing system (T) according to one of the preceding claims, wherein the pressure sensor unit (D) provides a weighing function to determine the weight of a quantity of coffee powder in a portafilter (R).

Images