Coffee grinders, coffee machines, and how to grind coffee in a coffee grinder

Abstract

A coffee grinder, a coffee machine, and a method for grinding coffee in a coffee grinder are provided. The coffee grinder features a two-part housing, which maximizes the stability of the coffee grinder while minimizing installation space. The coffee grinder also includes a DC motor. This motor allows the coffee grinder to provide ground coffee in the smallest possible installation space, with maximum lifespan and without long operational delays (e.g., due to coffee powder clogging). The coffee grinder can be used with a coffee machine. Additionally, the coffee grinder or coffee machine can be used with a coffee grinding method, providing the same benefits to the coffee machine and method.

Description

[Technical Field]

[0001] A coffee grinder, a coffee machine, and a method for grinding coffee in a coffee grinder are provided. The coffee grinder features a two-part housing, which maximizes the stability of the coffee grinder while minimizing installation space. The coffee grinder also includes a DC motor. This motor allows the coffee grinder to provide ground coffee in the smallest possible installation space, with maximum lifespan and without long operational delays (e.g., due to coffee powder clogging). The coffee grinder can be used with a coffee machine. Additionally, the coffee grinder or coffee machine can be used with a coffee grinding method, providing the same benefits to the coffee machine and method. [Background technology]

[0002] A coffee grinder for a fully or semi-automatic coffee machine consists of a multi-part housing, an upper bean container, and a drive consisting of an alternating current (AC) or direct current (DC) motor. Coffee beans are usually ground using a conical grinding wheel or grinding wheel. Grinding mechanisms with grinding wheels are typically used when high demands are placed on grinding performance and fineness of the grounds. Coffee beans are ground between two grinding wheels located in the coffee grinder housing. One of the grinding wheels remains stationary while the other rotates. Adjusting the distance between the two grinding wheels controls the fineness of the grind (coarse / fine). As a rule, a standard motor coupled to the grinding mechanism is used for the drive.

[0003] Coffee grinder manufacturers often source the motors for their coffee grinders from third-party manufacturers. The drawback here is that if the third-party manufacturer changes the motor (e.g., dimensions), the coffee machine manufacturer must also change the grinder housing, which may require additional components. This represents a high expenditure in terms of time and money for the coffee machine manufacturer.

[0004] Many coffee grinders are currently operated by AC motors. These have the advantage of being able to supply energy directly through the mains without distorting the coffee machine's power supply. However, AC motors have the disadvantage of having a relatively low starting torque. To be able to grind even relatively hard coffee beans, AC motors must be significantly oversized. This means that they are relatively large and require a lot of installation space for the coffee grinder. Another disadvantage of AC motors is their low efficiency, which means that they generate a high level of waste heat during operation, causing the temperature to rise.

[0005] One advantage of conventional DC motors is that, unlike AC motors, they can already produce high torque at start-up and operate under overload conditions, so they do not need to be oversized. However, a disadvantage is that the power supply unit for a DC motor must be designed accordingly large to be able to supply the high current required during start-up. A further disadvantage of operating a motor with a very high starting current under overload conditions is that it shortens the DC motor's lifespan. Conventional DC motors also have the disadvantage of not exhibiting stability at high frequencies and not allowing for speed monitoring. In addition, conventional DC motors regularly exhibit low efficiency, as high motor speed frequencies require the use of gearboxes. Another disadvantage is that the speed frequency depends on the load. Using such motors in coffee grinders means that the amount of ground coffee depends on the fill level of the bean container and the type of bean.

[0006] Based on this, it is an object of the present invention to provide a coffee grinder, a coffee machine, and a method for grinding coffee in a coffee grinder that no longer have at least one of the drawbacks known from the prior art. In particular, the coffee grinder, coffee machine, and method should be able to provide ground coffee with the smallest possible installation space, have the longest possible service life, and without long operational delays (e.g., due to coffee powder clogging). The coffee grinder, coffee machine, and method should preferably be able to provide high-quality ground coffee with minimal current load, minimal noise pollution, and / or consistent dosing capacity. Summary of the Invention [Problem to be solved by the invention]

[0007] The object is achieved by a coffee grinder having the features of claim 1, a coffee machine having the features of claim 12 and a method having the features of claim 14. The dependent claims show advantageous embodiments. [Means for solving the problem]

[0008] According to the invention, the coffee grinder comprises: a) an upper housing portion having an interior space suitable for holding coffee beans; b) a lower housing part connected to the upper housing part and having an interior space suitable for holding a DC motor (preferably a brushless DC motor); c) a grinding disc assembly including or consisting of an upper, non-rotatable first grinding disc and a lower, rotatable second grinding disc, said first grinding disc being positioned opposite said second grinding disc, said coffee grinder being configured to vary the distance from said first grinding disc to said second grinding disc; d) a DC motor (preferably a brushless DC motor) having a stator, a rotor, and a motor shaft, the motor shaft being connected to the rotor and the second grinding disk, the stator and the rotor being disposed within the interior space of the lower housing, and the motor shaft being disposed within the lower housing and at least partially within the upper housing; Equipped with The coffee grinder is configured to rotate the second grinding disc relative to the first grinding disc by moving the rotor of the DC motor. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 shows a schematic diagram of the interior of a particular coffee grinder design according to the present invention. [Figure 2] FIG. 2 shows a schematic cross-section of a particular coffee grinder design according to the invention, showing further parts of the coffee grinder in addition to those shown in FIG. [Figure 3] FIG. 3 shows a schematic representation of the individual parts of a particular coffee grinder design according to the present invention and how they are assembled into a complete coffee grinder. [Figure 4A] FIG. 4A shows the connection between the upper housing part 1 and the lower housing part 3 via a clamping ring 12 for a particular coffee grinder design according to the present invention. [Figure 4B] Figure 4B shows the connection between the upper housing 1 and the lower housing 3 via a clamp ring 12 for a particular coffee grinder design according to the present invention. Figure 4B shows that the clamp ring 12 is used to secure the upper housing 1 to the lower housing 3 via a threaded connection 11. DETAILED DESCRIPTION OF THE INVENTION

[0010] The coffee grinder according to the invention is ideal for providing ground coffee in the smallest possible installation space, with maximum service life and without long operational delays (e.g. due to clogging of coffee powder).

[0011] This is because the grinder housing consists of only two parts, requiring fewer components and connecting elements, thus enabling a smaller design and greater long-term stability. The required installation space is further reduced by locating the DC motor inside the coffee grinder housing (specifically, in the lower part of the housing). Furthermore, if the DC motor is equipped with a rotational position sensor, the speed frequency of the DC motor can be controlled and even adjusted. Among other things, the DC motor can also rotate clockwise and counterclockwise, thus quickly releasing the grinding wheel that becomes stuck during operation due to coffee residue and allowing operation to continue, thus avoiding longer operational delays due to clogged coffee powder and potentially extending the life of the coffee grinder.

[0012] Using a brushless DC motor instead of a DC motor allows the coffee grinder to minimize current load, minimize noise pollution, have a longer lifespan, and provide consistent dosing volume, all while providing high-quality ground coffee in a small installation space. While this motor lacks brushes like a conventional DC motor, it is electronically commutated, making it less susceptible to wear and tear and quieter during operation. Furthermore, brushless DC motors are significantly more energy efficient than conventional DC motors and require less installation space (due to the lack of brushes) for the same power output as conventional DC or AC motors. Brushless DC motors generate less heat than conventional DC motors, ensuring high-quality ground coffee. Furthermore, brushless DC motors inherently have a rotation angle sensor that can be used to adjust their speed frequency. This means that any potential drop in speed frequency under high loads, for example, can be quickly readjusted (i.e., compensated for by increasing motor power), thus ensuring a consistent dosing volume.

[0013] The upper housing of the coffee grinder can be connected to the lower housing via a reversible connection. The reversible connection is preferably selected from the group consisting of a friction connection, a form-fit connection, and combinations thereof. Particularly preferred are reversible connections selected from the group consisting of a clamp connection, a screw connection, a clip connection, a snap hook connection, a connection via a corrugated surface, and combinations thereof. In particular, the reversible connection is a screw clamp connection via a clamp ring. The advantage of a connection via a clamp ring is that the upper housing can be rotated 360° relative to the lower housing. This means that even with a fully assembled coffee grinder, the ground coffee outlet (e.g., the through-opening in the upper part of the coffee grinder housing) can be flexibly rotated in the desired direction. For example, this can be an advantage if a coffee machine has two coffee grinders according to the present invention and the ground coffee outlets of both grinders must be adjusted to the inlets of the coffee machine's brewing group. This adjustment can therefore be performed more quickly and easily.

[0014] The coffee grinder may have a through opening from the interior space of the coffee grinder to the exterior space of the coffee grinder and may be configured to transport ground coffee through the through opening (in other words, the coffee grinder may have an outlet for the ground coffee). The through opening is preferably arranged in the upper part of the housing. Furthermore, the through opening is preferably connected to a conduit, which is optionally connected to the upper housing part by a connection selected from the group consisting of a plug connection, a threaded connection, and combinations thereof. The conduit may facilitate adjusting or guiding the outlet for the ground coffee to the inlet of the brewing group of the coffee machine or to the portafilter of the coffee machine.

[0015] To support the motor shaft, the coffee grinder may have a bearing element in the lower part of the housing.

[0016] The bearing element preferably has an external thread that screws into the housing lower part, the external thread preferably having a pitch in the range of 0.2 to 1.0 mm, particularly preferably 0.3 to 0.8 mm, very particularly preferably 0.4 to 0.6 mm, in particular 0.5 mm. This range of pitch has been found to be advantageous for fine-tuning the distance between the second grinding disk and the first grinding disk, i.e., for fine-tuning the grinding degree.

[0017] In an advantageous embodiment, the bearing element is preferably connected to the variable displacement motor via a gear wheel that engages with a pinion of the variable displacement motor. The variable displacement motor is configured in particular to change the position of the bearing element and the motor shaft mounted therein towards the longitudinal axis of the motor shaft. Optionally, the variable displacement motor may be constituted by a coffee grinder or a coffee machine equipped with a coffee grinder according to the invention. In principle, as a possible alternative to this preferred embodiment, the position of the bearing element and the motor shaft mounted thereon can be changed in the direction of the longitudinal axis of the motor shaft without the aid of a user, for example by the user manually rotating the bearing element.

[0018] The motor shaft of the DC motor is preferably configured to change its position along its longitudinal axis. When the motor shaft is connected to a second grinding plate, this configuration offers the advantage that the distance between the second grinding plate and the first grinding plate (and therefore the fine grinding setting of the coffee beans) can be adjusted by moving the motor shaft axially. To achieve this, the motor shaft is preferably connected to a bearing element of a motor shaft mount in a region of the motor shaft arranged in the lower housing. Thus, the variable displacement motor for a coffee grinder or a coffee machine including a coffee grinder is configured to change the position of the bearing element and the motor shaft mounted therein along the longitudinal axis of the motor shaft by rotating its rotor.

[0019] Furthermore, the motor shaft can be connected to a rotor of a DC motor in a region of the motor shaft located in the lower housing portion, the DC motor being configured to rotate the rotor to rotate the motor shaft about its longitudinal axis.

[0020] Alternatively, the motor shaft can be connected to a second (i.e., lower, rotatable) grinding disk via a grinding disk carrier, preferably in the area of ​​the motor shaft located inside the upper housing. The advantage of connecting the motor shaft to the second grinding disk using a grinding disk bracket is that the power transmission connection between the motor shaft and the second grinding disk can be established simply and cost-effectively. For example, when replacing the second grinding disk, there is no need to adjust the grinding disk to the motor shaft's shape. The relatively direct connection between the second grinding disk and the motor shaft via the grinding disk bracket also improves the concentricity and axial runout of the second grinding disk compared to coffee grinders with multiple adapters and drivers. Improving concentricity and axial runout ensures that the fine grind setting is as consistent as possible during operation of the coffee grinder.

[0021] The first grinding disc and / or the second grinding disc may comprise or consist of a material selected from the group consisting of metal, ceramic, and combinations thereof, preferably a material selected from the group consisting of steel, ceramic, and combinations thereof, in particular a material selected from the group consisting of X210CRW12 steel and Al2O3 ceramic.

[0022] Furthermore, the first grinding disc and / or the second grinding disc may have an outer diameter in the range of 30 to 80 cm, preferably 55 to 70 cm, in particular 65 cm.

[0023] Furthermore, the first grinding disk and / or the second grinding disk may be disposed in the upper part of the housing.

[0024] The coffee grinder may have an infeed element (for coffee) disposed in the upper housing. The infeed element may have a spindle with a spindle axis. The infeed element is preferably configured to rotate (about its spindle axis) and, in doing so, transport coffee beans to the grinding disk arrangement. The advantage of this is that the coffee beans are evenly delivered to the grinding disk arrangement, thereby ensuring more consistent grinding results (e.g., in terms of grind volume and / or fine grind setting). The infeed element may have a protective guard configured to prevent it from reaching the interior of the upper housing. This helps prevent potential damage to the coffee grinder user. The infeed element is preferably connected to a second, lower, rotatable grinding disk. This means that the infeed element can be rotated by rotating the second grinding disk, or in other words, the infeed element can rotate together with the second grinding disk. The infeed element is preferably threaded onto the motor shaft (and the second, lower, rotatable grinding disk).

[0025] The lower rotatable second grinding disk and the grinding disk bracket may be one piece, in which case replacing the second grinding disk also involves replacing the grinding disk bracket.

[0026] In a preferred embodiment, the lower, rotatable second grinding disc is connected to the grinding disc bracket via a connection selected from the group consisting of a frictional connection, a form-fit connection, and combinations thereof, and in particular a threaded connection. The advantage of this design is that the grinding disc bracket does not need to be replaced when the second grinding disc is replaced. This saves material and costs, making it more economical and environmentally friendly.

[0027] DC motors can be brushed or brushless. The advantage of brushless DC motors is that they already have a rotational position sensor, which can be used to adjust the speed frequency and maintain a consistent coffee grinder dose. Furthermore, because they lack brushes to conduct electricity, brushless DC motors generate less heat during operation than conventional DC motors, ensuring higher-quality ground coffee. Brushless DC motors lack carbon, resulting in lower current loads and a longer service life (due to the absence of friction losses due to brushes). Furthermore, brushless DC motors allow for quieter operation (due to the absence of noise from carbon friction) and more compact coffee grinder designs (due to the absence of carbon taking up space).

[0028] A preferred DC motor is a DC motor without a housing, a DC motor with optional brushes without a housing, or a brushless DC motor without a housing. One advantage of a DC motor without a housing is that coffee grinder manufacturers who purchase a DC motor without a housing (optionally brushless) from a third-party manufacturer are no longer dependent on the manufacturer's specific motor housing shape, which may also be subject to change. This increases the coffee grinder manufacturer's flexibility and reduces production costs. Furthermore, a DC motor without a housing (optionally brushless) occupies less space than a DC motor with a housing (optionally brushless), further reducing the installation space required for the coffee grinder. This is because, in this embodiment, the lower housing (and at least some areas of the upper housing) of a coffee grinder according to the present invention can represent the (only) housing of the housingless DC motor.

[0029] DC motors can have wattages ranging from 50 to 500 watts. Wattages in this range have proven to be advantageous for grinding coffee.

[0030] In a preferred embodiment, the DC motor has a height in the range of 25 to 70 mm, particularly preferably 35 to 45 mm, in particular 40 mm, and / or a diameter in the range of 50 to 120 mm. These dimensions make it possible to provide a very compact coffee grinder.

[0031] The coffee grinder, preferably the DC motor of the coffee grinder, may have a control unit configured to control or adjust the speed frequency of the DC motor. Furthermore, the control unit may be configured to control or adjust the direction in which the rotor of the DC motor rotates. For adjustment, the DC motor requires a rotational position sensor.

[0032] In a preferred embodiment, the DC motor therefore has a rotational position sensor, preferably selected from the group consisting of optical rotational position sensors, magnetic rotational position sensors, and combinations thereof, and particularly preferably comprising or consisting of Hall sensors and / or GMR sensors. The advantage of a rotational position sensor is that it allows control of the DC motor speed frequency, which means that possible drops in speed frequency due to high load can be quickly compensated for, thus ensuring a consistent dosing capacity of the coffee grinder.

[0033] Preferably, the control unit for the coffee grinder, preferably the control unit for the DC motor of the coffee grinder, is configured to control the DC motor speed frequency based on at least one signal from the rotational position sensor.

[0034] Furthermore, the control unit for the coffee grinder, preferably the control unit for the DC motor of the coffee grinder, is preferably configured to control or adjust the direction in which the rotor of the DC motor rotates based on at least one signal from the rotational position sensor. By controlling the direction of rotation, the first and second grinding wheels can be prevented from becoming clogged with coffee beans or coffee powder (i.e., which could block the grinder), allowing the coffee grinder to continue operating.

[0035] Therefore, the control unit of the coffee grinder, preferably the control unit of the DC motor of the coffee grinder, is preferably configured to detect a blockage in the DC motor based on at least one signal from the rotational position sensor and, if a blockage is detected, to reverse the direction of rotation of the DC motor for a particular period of time, in particular 1 to 5 seconds, and / or for a particular degree of rotation, in particular 0.25 to 10 rotations.

[0036] In a further preferred embodiment, the control unit of the coffee grinder, preferably the control unit of the DC motor of the coffee grinder, is configured to detect the grinding point of the first grinding disk over the second grinding disk based on at least one signal from the rotational position sensor and, if a grinding point is detected, define this as the coffee grinder setting for best grinding. To detect the grinding point, in addition to the at least one signal from the rotational position sensor, the current consumption of the DC motor is preferably also taken into account, whereby the grinding point is detected by a decrease in speed frequency at constant current consumption or by an increase in current consumption at constant speed frequency.

[0037] The upper and / or lower portions of the coffee grinder housing may have a wall thickness of 1 to 5 mm in at least some areas.

[0038] The upper and / or lower housing of the coffee grinder may comprise or consist of a material selected from the group consisting of metal, plastic, and combinations thereof, preferably die-cast aluminum, die-cast zinc, steel, plastic, and combinations thereof.

[0039] Furthermore, the upper and / or lower housing of the coffee grinder may have a height in the range of 50 to 150 mm, at least in some areas.

[0040] Alternatively, the upper and / or lower housing parts of the coffee grinder may have a diameter in the range of 50 to 150 mm, at least in some areas.

[0041] Furthermore, the upper and / or lower housing part of the coffee grinder may have the shape of a hollow cylinder in at least some regions.

[0042] A sensor element for detecting the degree of grinding can be arranged at the base of the lower part of the housing of the coffee grinder. This sensor element is configured to detect the distance between the sensor element and a bearing element for mounting the motor shaft of the DC motor. A control unit of the coffee grinder according to the invention, or a control unit of a coffee machine including the coffee grinder according to the invention, can be configured to determine the degree of grinding of the coffee grinder according to the invention (or of the coffee) from information from the sensor element.

[0043] According to the invention there is also provided a coffee machine comprising a coffee grinder according to the invention, the coffee machine being preferably a semi-automatic or fully automatic coffee machine.

[0044] The DC motor of the coffee grinder of the coffee machine may have a rotational position sensor, preferably selected from the group consisting of an optical rotational position sensor, a magnetic rotational position sensor, and combinations thereof, and the rotational position sensor particularly preferably comprises or consists of a Hall sensor and / or a GMR sensor.

[0045] The control unit for the coffee grinder and / or coffee machine may be configured to adjust the DC motor speed frequency based on at least one signal from the rotational position sensor.

[0046] Furthermore, the control unit of the coffee grinder and / or coffee machine may be configured to control in which direction the rotor of the DC motor rotates.

[0047] Furthermore, the control unit of the coffee grinder and / or coffee machine may be configured to detect blockages in the DC motor and, if a blockage is detected, reverse the direction in which the DC motor rotates for a particular period of time, in particular 1 to 5 seconds, and / or for a particular degree of rotation, in particular 0.25 to 10 rotations.

[0048] Alternatively, the control unit of the coffee grinder and / or coffee machine can be configured to detect the grinding point of the first grinding disk on the second grinding disk and, if the grinding point is detected, define this as the finest grind setting of the coffee grinder, wherein to detect the grinding point, in addition to at least one signal from the rotational position sensor, optionally also the current consumption of the DC motor is taken into account, and the grinding point is optionally detected by a decrease in rotational speed frequency at a constant current consumption or by an increase in current consumption at a constant speed frequency.

[0049] According to the present invention, there is also provided a method for grinding coffee in a coffee grinder, comprising the following steps: A) Providing a coffee grinder or coffee machine according to the present invention; B) filling the upper portion of the coffee grinder housing with coffee beans or coarsely ground coffee; C) Grinding coffee beans or coarsely ground coffee.

[0050] The DC motor of the coffee grinder of the coffee machine may have a rotational position sensor, preferably selected from the group consisting of an optical rotational position sensor, a magnetic rotational position sensor, and combinations thereof, and the rotational position sensor particularly preferably comprises or consists of a Hall sensor and / or a GMR sensor.

[0051] In this manner, the DC motor speed frequency can be controlled based on at least one signal from the rotational position sensor.

[0052] Additionally, the method can be used to control which direction a rotor of a DC motor rotates based on at least one signal from a rotational position sensor.

[0053] Further, in the method, an obstruction in the DC motor can be detected based on at least one signal from a rotational position sensor, and if an obstruction is detected, the direction in which the DC motor rotates can be reversed for a specific period of time, particularly 1 to 5 seconds, and / or for a specific degree of rotation, particularly 0.25 to 10 rotations.

[0054] Apart from that, the method enables detection of the grinding point of the first grinding disk on the second grinding disk based on at least one signal from the rotational position sensor, and if the grinding point is detected, the grinding point can be defined as the finest grind setting of the coffee grinder, and in addition to the at least one signal from the rotational position sensor, the current consumption of the DC motor is optionally also taken into account to detect the grinding point, and the grinding point is optionally detected by a decrease in rotational speed frequency at a constant current consumption or by an increase in current consumption at a constant speed frequency.

[0055] The above method steps can be performed by a control unit of a DC motor, a control unit of a coffee grinder or a control unit of a coffee machine.

[0056] The subject matter according to the invention will now be described in more detail with reference to the following drawings, without intending to be limited to the particular embodiments shown therein.

[0057] FIG. 1 shows a schematic diagram of the interior of a particular coffee grinder design according to the present invention. The coffee grinder comprises an upper housing 1 having an interior space 2 configured to hold coffee beans and a lower housing 3 connected to the upper housing 1. In this design, the upper housing 1 can be seen to be connected to the lower housing 3 by a screw clamp connection 11 via a clamp ring 12. The clamp ring 12 allows the upper housing 1 to rotate 360° relative to the lower housing 3. The arrangement of an infeed element 21 and its protective guard 22 is also shown here. The infeed element 21 is used to feed coffee beans and secures the first grinding disk 5 to the upper housing 1 of the coffee grinder. The protective guard prevents the user from accidentally accessing the interior space 2 of the upper housing 1, thus preventing potential user injury. The upper housing 1 has a through opening connected to a conduit 14. The conduit 14 is attached to the upper housing 1 via a threaded connection 15.

[0058] FIG. 2 shows a schematic cross-section of a particular coffee grinder design according to the present invention, illustrating additional portions of the coffee grinder in addition to those shown in FIG. 1 . For example, the interior space 4 of the lower housing 3 of the coffee grinder is now shown in more detail. It can be seen that the coffee grinder includes a grinding disk arrangement consisting of an upper, non-rotatable first grinding disk 5 and a lower, rotatable second grinding disk 6, with the first grinding disk 5 positioned opposite the second grinding disk 6. The coffee grinder is configured to vary the distance between the first grinding disk 5 and the second grinding disk 6. Additionally, the coffee machine includes a brushless DC motor having a stator 8 and a rotor 9, the rotor 9 being connected to the second grinding disk 6. The coffee grinder is configured such that movement of the brushless DC motor rotor 9, transmitted to the motor shaft 10, rotates the second grinding disk 6 relative to the first grinding disk 5. It can also be seen that the motor shaft 10 is connected to a bearing element 16 for mounting the motor shaft 10 via a press fit. The bearing element 16 has an external thread 17 through which it is screwed into the lower housing part 3. Furthermore, the bearing element 16 is connected to a gear wheel 19 that engages a pinion (not shown) in a variable displacement motor 18. The variable displacement motor 18 can be used to move the bearing element 16, and thus the motor shaft 10, in one direction along the longitudinal axis of the motor shaft 10, thereby moving the second grinding disc 6, which is connected to the motor shaft 10 via the grinding disc bracket, toward or away from the first grinding disc (in other words, changing the grind size of the coffee). In this design, a sensor element 25 is located at the bottom of the lower housing part 3 to detect the fine grind setting. This sensor element is configured to detect the removal of the sensor element 25 from the bearing element 16. The fine grind setting of the coffee grinder (or coffee) can be derived from this distance information.

[0059] FIG. 3 shows a schematic representation of the individual parts of a particular coffee grinder design according to the present invention and how they are assembled into a complete coffee grinder.

[0060] Figures 4A and 4B show the connection between the upper housing 1 and the lower housing 3 via a clamping ring 12 for a particular coffee grinder design according to the present invention. Figure 4B shows that the clamping ring 12 is used to secure the upper housing 1 to the lower housing 3 via a threaded connection 11. The advantage of the clamping ring 12 is that the upper housing 1 can be rotated 360° relative to the lower housing, allowing the ground coffee outlet located in the upper housing to be easily and flexibly moved as needed. [Explanation of symbols]

[0061] 1: Top of housing 2: Internal space at the top of the housing 3: Lower part of the housing (or part of it) 4: Internal space under the housing 5: Upper, non-rotatable first grinding disc 6: Lower rotatable second grinding disc 7: Brushless DC motor 8: Stator of a brushless DC motor 9: Brushless DC motor rotor 10: Motor shaft of brushless DC motor 11: Threaded connection 12: Clamp ring 13: Through opening 14: Conduit 15: Threaded connection 16: Bearing element for mounting the motor shaft 17 External thread of bearing element for mounting motor shaft 18: Variable displacement motor (e.g., the coffee grinder itself) 19: Gear Wheel 20: Grinding disk bracket (to support the lower rotatable second grinding disk) 21: Infeed elements 22: Infeed element protection guard 23: Upper motor bearing 24: Lower engine bearing 25: Sensor to detect the degree of crushing

Claims

1. 1. A coffee grinder having a two-part housing, a) an upper housing portion having an interior space suitable for holding coffee beans; b) a lower housing portion connected to the upper housing portion and having an interior space suitable for holding a direct current (DC) motor; c) a grinding disk assembly including or consisting of an upper, non-rotatable first grinding disk and a lower, rotatable second grinding disk, the first grinding disk being positioned opposite the second grinding disk, and the coffee grinder being configured to vary the distance from the first grinding disk to the second grinding disk; d) a DC motor having a stator, a rotor, and a motor shaft, the motor shaft being connected to the rotor and the second grinding disk, the stator and the rotor being disposed within the interior space of the lower housing, and the motor shaft being disposed in at least some areas within the lower housing and the upper housing; Including, The coffee grinder is configured to rotate the second grinding plate relative to the first grinding plate by moving the rotor of the DC motor.

2. Coffee grinder according to claim 1, characterized in that the upper housing part is connected to the lower housing part by a reversible connection, which is preferably selected from the group consisting of a friction connection, a form-fit connection and combinations thereof, which is selected from the group consisting of a clamp connection, a screw connection, a clip connection, a snap hook connection, a connection via a corrugated surface and combinations thereof, and which is in particular a screw clamp connection via a clamping ring.

3. The coffee grinder has a through opening from an interior space of the coffee grinder to an exterior space of the coffee grinder and is configured to convey ground coffee through the through opening, the through opening preferably comprising: i) located on the top of the housing; and / or ii) connected to a conduit, said conduit being optionally connected and screwed into said housing upper portion via a connection selected from the group consisting of a plug-in connection, a threaded connection, and combinations thereof.

4. The coffee grinder has a bearing element in the lower housing portion for mounting the motor shaft, the bearing element preferably comprising: i) has an external thread that is screwed into the housing lower part, the external thread preferably having a pitch in the range of 0.2 mm to 1.0 mm, particularly preferably 0.3 mm to 0.8 mm, very particularly preferably 0.4 mm to 0.6 mm, in particular 0.5 mm, and / or ii) a variable displacement motor connected, preferably via a gear engaging a pinion of the variable displacement motor, the variable displacement motor being particularly configured to vary the position of the bearing element and the motor shaft mounted therein towards the longitudinal axis of the motor shaft, the variable displacement motor optionally being constituted by the coffee grinder or by a coffee machine comprising the coffee grinder.

5. The motor shaft of the DC motor is preferably configured to change position in the direction of the longitudinal axis of the motor shaft, and the motor shaft preferably has: i) connected to a bearing element for mounting the motor shaft, preferably in a region of the motor shaft arranged in the lower housing, the variable displacement motor of the coffee grinder or of a coffee machine including the coffee grinder being configured to vary the position of the bearing element and of the motor shaft mounted therein in the direction of the longitudinal axis of the motor shaft by rotating its rotor; and / or ii) connected to the rotor of the DC motor in a region of the motor shaft located in the lower housing portion, the DC motor being configured to rotate the rotor, thereby rotating the motor shaft about its longitudinal axis; and / or iii) connected to a lower, rotatable second grinding disk via a grinding disk bracket, partly preferably in the region of the motor shaft located inside the upper housing part.

6. The first grinding disc and / or the second grinding disc are i) a material selected from the group consisting of metals, ceramics, and combinations thereof, preferably a material selected from the group consisting of steel, ceramics, and combinations thereof, more preferably X210CRW12 steel and Al ２ O ３ and / or a material selected from the group consisting of ceramics; ii) has an outer diameter in the range of 30 to 80 cm, preferably 55 to 70 cm, in particular 65 cm; and / or iii) Located on the upper part of the housing.

7. The second grinding disk is i) the grinding disk bracket is one piece; or ii) In an advantageous embodiment, the lower, rotatable second grinding disk is preferably connected to the grinding disk bracket via a connection selected from the group consisting of a friction connection, a form-fit connection and combinations thereof, the connection being in particular a threaded connection; Coffee grinder according to any one of claims 1 to 6.

8. The DC motor i) a DC motor with brushes or a brushless DC motor, preferably a DC motor with brushes but without a housing, or a brushless DC motor without a housing; and / or ii) having a wattage in the range of 50 to 500 watts; and / or iii) have a height in the range of 25 to 70 mm, particularly preferably 35 to 45 mm, in particular 40 mm, and / or iv) having a diameter in the range of 50 to 120 mm; Coffee grinder according to any one of claims 1 to 7.

9. The coffee grinder, preferably the DC motor of the coffee grinder, preferably comprises: i) controlling or adjusting the speed frequency of said DC motor; and / or ii) controlling or adjusting the direction in which the rotor of the DC motor rotates; Coffee grinder according to any one of claims 1 to 8.

10. the DC motor has a rotational position sensor, which is preferably selected from the group consisting of an optical rotational position sensor, a magnetic rotational position sensor and a combination thereof, which particularly preferably comprises or consists of a Hall sensor and / or a GMR sensor, and preferably a control unit of the coffee grinder, preferably a control unit of the DC motor of the coffee grinder, is preferably configured based on at least one signal of the rotational position sensor, i) controlling or adjusting the speed frequency of said DC motor; and / or ii) controlling or adjusting the direction in which the rotor of the DC motor rotates; and / or iii) detecting a blockage of the DC motor and, if a blockage is detected, reversing the direction of rotation of the DC motor for a specific period of time, in particular 1-5 seconds, and / or for a specific degree of rotation, in particular 0.25-10 rotations; and / or 10. A coffee grinder according to claim 9, further comprising: detecting the grinding point of the first grinding disk on the second grinding disk; and, if detected, defining this as the setting for the finest grind of the coffee grinder; and, in addition to the at least one signal from the rotational position sensor, preferably also taking into account the current consumption of the DC motor to detect the grinding point; and, optionally, the grinding point being detected by a decrease in speed frequency at constant current consumption or by an increase in current consumption at constant speed frequency.

11. The upper housing portion and / or the lower housing portion are i) have a wall thickness in the range of at least 1-5 mm in some areas; and / or ii) comprising or consisting of a material selected from the group consisting of metal, plastic, and combinations thereof, preferably a material selected from the group consisting of die-cast aluminum, die-cast zinc, steel, plastic, and combinations thereof; and / or iii) has a height in the range of 50 to 150 mm; and / or iv) diameter is in the range of 50 to 150 mm; and / or v) has the shape of a hollow cylinder in at least some regions; Coffee grinder according to claim 10.

12. Coffee machine, preferably a semi-automatic or fully automatic coffee machine, comprising a coffee grinder according to any one of claims 1 to 11.

13. the DC motor has a rotational position sensor, which is preferably selected from the group consisting of an optical rotational position sensor, a magnetic rotational position sensor and a combination thereof, which particularly preferably comprises or consists of a Hall sensor and / or a GMR sensor, and preferably a control unit of the coffee grinder, preferably a control unit of the DC motor of the coffee grinder, is preferably configured based on at least one signal of the rotational position sensor, i) to adjust the speed frequency of said DC motor; and / or ii) to adjust the direction in which the rotor of the DC motor rotates; and / or iii) detecting blockage of the DC motor and, if a blockage is detected, reversing the direction of rotation of the DC motor for a specific period of time, in particular 1-5 seconds, and / or for a specific degree of rotation, in particular 0.25-10 rotations; and / or iv) detecting the grinding point of the first grinding disk on the second grinding disk, and if a grinding point is detected, defining this as the setting for the finest grind of the coffee grinder, and optionally taking into account the current consumption of the DC motor in addition to the at least one signal from the rotational position sensor to detect the grinding point, since the grinding point is optionally detected by a decrease in speed frequency at a constant current consumption or by an increase in current consumption at a constant speed frequency; Coffee machine according to claim 12,

14. 1. A method of grinding coffee in a coffee grinder, comprising: a) providing a coffee grinder according to any one of claims 1 to 11 or a coffee machine according to either claim 12 or 13; b) filling the upper portion of the coffee grinder housing with coffee beans or coarsely ground coffee; c) grinding the coffee beans or coarsely ground coffee.

15. The DC motor has a rotational position sensor, which is preferably selected from the group consisting of an optical rotational position sensor, a magnetic rotational position sensor, and a combination thereof, and the rotational position sensor particularly preferably includes or consists of a Hall sensor and / or a GMR sensor, and based on at least one signal of the rotational position sensor: i) the speed frequency of the DC motor is adjusted; and / or ii) adjusting the direction in which the rotor of the DC motor rotates; and / or iii) detecting a blockage of the DC motor and, if a blockage is detected, reversing the direction of rotation of the DC motor for a specific period of time, in particular 1-5 seconds, and / or for a specific degree of rotation, in particular 0.25-10 rotations; and / or iv) detecting the grinding point of the first grinding disk on the second grinding disk, and if detected, defining this as the setting for the finest grind of the coffee grinder, wherein in addition to the at least one signal from the rotational position sensor, the current consumption of the DC motor is preferably also taken into account to detect the grinding point, the grinding point being optionally detected by a decrease in speed frequency at a constant current consumption or by an increase in current consumption at a constant speed frequency, 15. The method according to claim 14, wherein the above-mentioned method steps are optionally implemented by a control unit of the DC motor, by a control unit of the coffee grinder or by a control unit of the coffee machine.

Images