Coffee grinder control system

Abstract

FIELD: control system for coffee grinder.SUBSTANCE: system comprising a hopper for containing coffee beans, configured to dispense ground coffee, and a mill motor for grinding coffee beans contained in the hopper, wherein the control system comprises: a load sensor unit for determining at least one operating parameter of the mill motor during a grinding operation, in which coffee beans in the hopper are ground by the mill motor for producing ground coffee, wherein the operating parameter of the mill motor relates to the load on the mill motor during the grinding operation; and a processor configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation, based on at least the operating parameter of the mill motor received from the load sensor unit.EFFECT: improving the coffee preparation process.16 cl, 4 dwg

Description

AREA OF TECHNOLOGY

[0001] The present invention relates to a control system for a coffee grinder.BACKGROUND OF THE INVENTION

[0002] To obtain the desired amount of ground coffee, a typical traditional coffee grinder control system operates either during the grinder's run time or during a certain number of motor revolutions. This traditional control system typically uses a lookup table to correlate different grind amount values ​​with the grinder's run time or motor revolutions. The user simply inputs the desired amount of ground coffee into the grinder, and the control system uses the lookup table to determine the run time or motor revolutions required to obtain the desired amount of ground coffee. The control system then runs the grinder based on the determined run time or motor revolutions.

[0003] The disadvantage of this traditional control system is that coffee bean characteristics (e.g., brand, hardness, type, grind size) inevitably affect the output of ground coffee from the grinder motor. Specifically, running the grinder motor for a given time or number of revolutions on hard coffee beans will inevitably result in a smaller amount of ground coffee than running the grinder motor for the same time or number of revolutions on soft coffee beans. Consequently, control based on the grinder motor's time or number of revolutions may lead to inaccuracies in the output of ground coffee from the grinder, which will affect the output of subsequent coffee preparation steps (e.g., tamping, brewing, etc.).

[0004] Another drawback of this traditional control system is that if the grinder is empty or blocked during operation, the user must manually determine the amount of ground coffee dispensed by the grinder up to that point and set the remaining operating time or the number of revolutions required to dispense the remaining ground coffee to achieve the desired amount. This manual process will inevitably lead to further inaccuracies. SUMMARY OF THE INVENTION

[0005] The object of the preferred embodiments of the present invention is to eliminate at least one of the disadvantages described above and / or at least provide the public with a useful choice.

[0006] In one aspect of the present invention, a control system is provided for a coffee grinder comprising a hopper for loading coffee beans from which ground coffee can be dispensed, and a mill motor for grinding coffee beans contained in the hopper, wherein the control system includes: a load sensor unit for measuring at least one operating parameter of the mill motor during a grinding process during which coffee beans in the hopper are ground to produce ground coffee, wherein the operating parameter of the mill motor relates to the load on the motor during the grinding operation; a processor configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation, based on at least the operating parameter of the mill motor received from the load sensor unit.

[0007] In one embodiment, the operating parameter of the mill motor includes the electric current driving the mill motor during the grinding operation, and the load sensor unit includes an electric sensor, such as a current sensor, for measuring the electric current driving the mill motor. In this embodiment, the processor can be configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the electric current measured by the current sensor over a certain period of time. The time period can be any of the following values: at least 10 milliseconds, at least 50 milliseconds, at least 100 milliseconds, at least 500 milliseconds, at least 1 second, or at least 5 seconds.

[0008] In an additional embodiment, the operating parameter of the mill motor includes the electrical power consumed by the mill motor during the grinding operation, and the load sensor unit comprises an electrical sensor, such as a current sensor for measuring the electrical current driving the mill motor, and / or a voltage sensor for measuring the voltage on the mill motor. In this embodiment, the processor can be configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation, based on the measured electrical power consumed by the mill motor over a certain period of time. The time period can be any of the values ​​of at least 10 milliseconds, at least 50 milliseconds, at least 100 milliseconds, at least 500 milliseconds, at least 1 second, or at least 5 seconds.

[0009] In another embodiment, the operating parameter of the mill motor includes the rotational speed of the mill motor during the grinding operation, and the load sensor unit includes a speed sensor for measuring the rotational speed of the mill motor. In this embodiment, the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the speed measured by the speed sensor for at least one revolution of the mill motor. In another embodiment, the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the speed measured by the speed sensor for the motor speed coefficient and the voltage coefficient.

[0010] In an additional embodiment, the grinding motor operating parameter includes the time required to complete a full or partial rotation of the grinding motor during the grinding operation, and the load sensor unit includes a sensor for measuring the rotation of the grinding motor. In this embodiment, the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the time measured by the sensor for measuring the rotation of the grinding motor.

[0011] The sensor preferably comprises a sensor component that can be placed on one of the dynamic parts or static parts of the coffee grinder. The sensor preferably comprises a reference component located on the other dynamic part or static part of the coffee grinder. The motor speed or the time required for the grinder motor to complete a full / partial rotation can preferably be determined in response to the sensor component detecting the reference component. For example, the motor speed or time can be determined when the reference component is aligned with the sensor component or is in close proximity to it. In one example, the sensor component is located on the dynamic part, while the reference component is located on the static part. In another example, the sensor component is located on the static part, while the reference component is located on the dynamic part.In one example, the dynamic part may be the rotating head of the mill motor or its rotating drive shaft. In one example, the static part is a portion of the mill motor housing close to or adjacent to the dynamic part.

[0012] In one embodiment, the sensor component may be a Hall effect sensor, and the reference component may be a magnet. The Hall effect sensor may be located on the mill motor housing, while the magnet is located on the mill drive shaft.

[0013] In another embodiment, the sensor component may be an optical switch or a photosensor, and the reference component may be an optical film.

[0014] The motor speed sensor may comprise a plurality of spaced sensor components and / or a plurality of spaced reference components for detecting a partial revolution of the mill motor. In one example, the sensor may comprise one sensor component and two or more spaced reference components.

[0015] In one embodiment, the amount of ground coffee dispensed from the hopper during the grinding operation is determined by the processor during the grinding period; and the processor is preferably further configured to: determine an accumulated amount of ground coffee based on a plurality of amounts of ground coffee determined during the grinding operation, wherein each determined amount of ground coffee relates to a corresponding grinding period. The period of the grinding operation may be a period of time or a turnover period. For example, the period may be any of the values ​​of at least 10 milliseconds, at least 50 milliseconds, at least 100 milliseconds, at least 500 milliseconds, at least 1 second, or at least 5 seconds.In an alternative embodiment, the period may be one of a partial revolution of the grinding motor (e.g., one-tenth, eighth, quarter, or half of a motor revolution), a full revolution of the grinding motor, or multiple revolutions of the grinding motor. The accumulated quantity is preferably stored in computer memory accessible to the processor. The accumulated quantity can be updated by the processor as each subsequent amount of ground coffee is determined during the grinding operation.

[0016] The processor may be further configured to: receive user input related to the required amount of ground coffee; and terminate the grinding operation when it is determined that the accumulated amount of ground coffee has reached the required amount of ground coffee. The coffee grinder may have an electronic selection system through which the user can enter user input related to the required amount of ground coffee.

[0017] The processor is preferably further configured to: in response to determining that the grinder motor load changes, continue updating the accumulated amount of ground coffee. The processor may update the accumulated amount of ground coffee with the corresponding amount of ground coffee after the grinding operation for this corresponding amount of ground coffee is completed. The processor preferably continues updating the accumulated amount of ground coffee at least until the accumulated amount reaches the required amount of ground coffee.

[0018] The processor may be further configured to: stop grinding and stop updating the accumulated amount of ground coffee in response to detecting that the grinder motor load is constant. In this example, the processor further provides a display on the coffee grinder's electrical display indicating that the hopper is empty or blocked in response to detecting that the grinder motor load is constant.

[0019] The processor may be further configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation depending on at least one characteristic of the coffee beans in the hopper.

[0020] In one aspect of the present invention, there is also provided a coffee grinder comprising: a hopper for containing coffee beans from which ground coffee can be dispensed; a mill motor for grinding the coffee beans contained in the hopper; and a control system, as described previously, for determining the amount of ground coffee dispensed from the hopper during a grinding operation performed by the mill motor, wherein the control system is configured to control the mill motor in response to the determined amount of ground coffee. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Embodiments of the present invention will now be described by way of non-limiting example with reference to the accompanying drawings, in which:

[0022] FIGURE 1 is a block diagram showing steps performed by a processor according to an embodiment of the present invention;

[0023] FIGURE 2 is a flow chart showing steps performed by a processor according to an embodiment of the present invention; and

[0024] FIGURES 3A and 3B show a coffee grinder according to the present invention. DESCRIPTION OF EMBODIMENTS

[0025] A control system for a coffee grinder according to an embodiment of the present invention implements the process shown in FIGURE 1. The coffee grinder has a coffee bean hopper from which ground coffee can be dispensed, and a mill motor for grinding the coffee beans contained in the hopper. The control system is configured to determine the amount of ground coffee from the hopper during the grinding operation performed by the mill motor, and to control the mill motor in response to the determined amount of ground coffee. The ground coffee from the coffee grinder is fed into a portafilter. In some embodiments, the portafilter may be located in a tamping mechanism, which is configured to tamp the ground coffee in the portafilter as soon as the desired amount of ground coffee is in the portafilter. The tamping mechanism may comprise an automatic auger tamper or a manual articulated tamper.For example, the tamping mechanism may be the mechanism described in WO 2012045112 A1 (entitled TAMPING AUGER, published April 12, 2012) and WO 2014165905 A1 (entitled IMPROVEMENTS TO COFFEE GRINDER, published October 16, 2014).

[0026] The control system comprises a processor configured to control the operation of the coffee grinder. The processor may be a microcontroller.

[0027] The control system includes an electronic user input device on which the user can enter the desired quantity of ground coffee and / or the desired grinding degree of the ground coffee. The electronic user input device may be, for example, a display screen. Based on the user-entered quantity and / or grinding degree of the ground coffee, the control system can determine, based on one or more lookup tables, the total amount of time required for the grinder motor to operate in grinding mode to obtain the desired quantity / grinding degree of the ground coffee. The total amount of time can be displayed on the display screen and updated when the grinder is operating to grind the coffee beans in the hopper.

[0028] The coffee grinder comprises a load sensor unit for detecting at least one operating parameter of the grinder motor during a grinding operation in which coffee beans in a hopper are ground by the grinder motor to produce ground coffee. The operating parameter of the grinder motor refers to the load on the grinder motor during the grinding operation. Specifically, the operating parameter of the grinder motor refers to the grinding resistance or grinding friction experienced by the grinder motor during the grinding operation, which will take into account the characteristics of the coffee beans (the hardness of the coffee bean and the degree of grinding of the ground coffee). For example, a hard coffee bean will create more resistance / friction during the grinding operation, while a soft coffee bean will create less resistance / friction during the grinding operation.The resistance / friction experienced by the mill motor can be determined from the electrical current consumed by the motor during the grinding operation, from the electrical power supplied to the motor during the grinding operation, and / or from the revolutions of the mill motor (e.g., the time required for the mill motor to complete a partial / full revolution, or the rotational speed of the mill motor).

[0029] For the process 100 shown in Figure 1, the load sensor unit is a current sensor for measuring the electric current driving the mill motor during the grinding operation. The mill motor will consume more electric current when grinding hard coffee beans and less electric current when grinding soft coffee beans. Accordingly, the processor can determine the load on the mill motor based on the electric current value. The processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the electric current value measured by the current sensor over a certain period of time. The time period can be any of the following values: at least 10 milliseconds, at least 50 milliseconds, at least 100 milliseconds, at least 500 milliseconds, at least 1 second, or at least 5 seconds.Alternatively, the period can represent a full or partial revolution of the grinder motor. A shorter period of time for measuring electrical current will provide a higher degree of accuracy for ground coffee from the grinder.

[0030] As shown in Figure 1, the process 100 implemented by the control system begins after the power supply to the coffee grinder (step 101). The control system keeps the coffee grinder in the off mode (step 102), in which the coffee grinder does not perform the grinding operation until the control system detects a portafilter located at the lower outlet of the coffee grinder (step 103). This step (step 103) is an additional or optional step for devices that have a system for detecting a portafilter. After detecting the portafilter, the control system puts the coffee grinder into the standby mode (step 104), in which the coffee grinder receives input data related to the characteristics of the coffee beans or detects them, and also accepts user input on the desired (or target) amount of ground coffee. The user can also set the desired degree of grinding for the ground coffee beans.In this regard, the control system has a computer memory for storing one or more look-up tables containing information related to various coffee bean profiles and their characteristics (including the operating parameter of the mill motor described above), and has a display screen on which the user can select the coffee beans that have been placed in the hopper.

[0031] The coffee grinder comprises a switch that is configured to activate a grinding operation (step 105) after the required amount of coffee is loaded into the coffee grinder by the user. The coffee grinder has a portafilter sensor for measuring the level of ground coffee in the portafilter, and the control system is configured to determine the level of ground coffee inside the portafilter based on measurements received from the portafilter sensor (step 106). This step (step 106) is an additional or optional step for devices that have a tamping mechanism for tamping the ground coffee in the portafilter. The amount of ground coffee in the portafilter can be determined by measuring the current of the auger motor of the tamping mechanism for tamping the coffee in the portafilter or using the sensor of the tamping mechanism.If the amount of ground coffee in the portafilter meets the required level (step 107), the control system turns off the grinder motor and notifies the user, for example, on the display screen, that the required level of ground coffee in the portafilter has been reached (step 108). Conversely, if the amount of ground coffee in the portafilter is below the required level, the control system turns on the grinder motor to grind the coffee beans in the hopper (step 109). The control system implements proportional-integral-derivative (PID) control of the grinder motor during the grinding operation.

[0032] The control system starts a timer for a predetermined period (step 110). This period is the period during which the grinding operation is performed. As mentioned previously, the period can be at least 10 milliseconds, at least 50 milliseconds, at least 100 milliseconds, at least 500 milliseconds, at least 1 second, or at least 5 seconds. In another example, the period can be a full or partial revolution (rotation) of the grinder motor. A shorter period will ensure a higher degree of accuracy for ground coffee from the grinder. The grinder system includes a current sensor for measuring the electric current driving the grinder motor. The control system is configured to determine the electric current measured by the current sensor during this period of time (step 111).The electrical current determined during this period of time is compared with the corresponding value from a look-up table (step 112), from which the amount of ground coffee during this predetermined period can be determined.

[0033] In one example, a lookup table maps electrical current values ​​to ground coffee quantities for different coffee bean characteristics. The control system is configured to update the accumulated ground coffee quantity based on a determined ground coffee quantity corresponding to each measured electrical current value over a period of time. The grinder motor operates until the accumulated ground coffee quantity reaches the desired ground coffee quantity. The lookup table corresponding to this example is shown below. where m and n are integers greater than zero, θ mis the corresponding characteristic of coffee beans, I mn represents the value of electric current corresponding to the characteristic of coffee beans θ m , and Q mn represents the amount of ground coffee corresponding to I mn. The value of the accumulated amount of ground coffee Q T represents the sum of the quantities of ground coffee Q m (i) during the operation of the mill motor for i.e. preset periods of time until the value of the accumulated amount of ground coffee Q T will not reach the required amount of ground coffee Q D , according to the formula below. The accumulated amount of ground coffee is updated in the computer's memory after each iteration.

[0034] Another example in the reference table compares different coffee bean characteristics with the mill motor current coefficients. In this regard, the current drawn by the motor to grind two equal quantities of different coffee beans will vary depending on the coffee bean characteristics. For example, harder beans require more current drawn by the mill motor during grinding, while softer beans require less current drawn by the mill motor during grinding at the same voltage. Coefficient C i The mill motor current is designed to compensate for the influence of the grain characteristics on the determination of the amount of ground coffee based on the measured electric current value or both the measured electric current value and the measured voltage value. During the i-th specified time period t, if the coefficient is known electricity consumption E ithe mill motor during this given period of time can be estimated based on the voltage V i on the engine, electric current I i, consumed by the engine, and the coefficient C i mill motor current. Amount of ground coffee Over a predetermined period, the energy consumption can be subsequently determined using another reference table that correlates energy consumption values ​​with ground coffee quantities. The reference tables and calculations for the accumulated ground coffee quantity value according to this example are shown below. According to the first reference table below, the system assumes that C iwill be constant for different values ​​of electrical current consumption with the same coffee bean characteristic. In one embodiment, the first lookup table may include a column for the electrical current consumed by the motor, with each value of the coffee bean characteristic associated with a range or set of electrical current values. In this embodiment, the coefficients related to the coffee bean characteristic will vary depending on the electrical current consumed by the motor. That is, in this embodiment, the system assumes that coefficient C i The coefficients may vary depending on the different values ​​of electrical current consumption for the same coffee bean characteristics. These coefficients are determined during production and pre-programmed into the system. The value of electricity consumption during a predetermined period t: Accumulated amount of Q T ground coffee is the sum of the quantities Q i ground coffee during the operation of the mill motor for the i-th preset period of time until the accumulated amount Q T ground coffee will not reach the required amount Q D ground coffee. The accumulated amount of ground coffee is updated in the computer's memory after each iteration.

[0035] A constant electric current for a period of time or an electric current without a load (for example, an electric current that indicates no resistance to the grinder motor) for a period of time indicates that the hopper is empty or blocked in the coffee grinder. Specifically, a constant electric current or an electric current without a load will indicate that the motor is running at a constant speed and does not experience any resistance / load / friction, which would be the case in the case of an empty hopper or a blockage. If the control system determines that the coffee grinder is out of beans or that it is blocked (step 113), the control system turns off the grinder motor and provides user notifications, for example on the display screen, that the coffee grinder is empty or blocked (step 115).In addition, the accumulated amount of ground coffee is stored in the computer's memory so that when the grinder is refilled with coffee beans or unlocked, the control system resumes the previously stored accumulated amount. The grinder then returns to standby mode (step 104). On the other hand, if the processor determines that the grinder is neither empty nor locked, the control system calculates the amount of ground coffee produced during a predetermined period based on the electric current consumption of the grinder motor during this period (step 116). The amount of ground coffee produced during this predetermined period is added to the accumulated amount of ground coffee stored in the computer's memory. The ground coffee produced during this predetermined period is fed into the portafilter.The time remaining to reach the required amount of ground coffee can be updated based on the accumulated amount of ground coffee over a preset period of time.

[0036] The control system is configured to subsequently determine the level of ground coffee in the portafilter (step 117). This step (step 117) is an additional or optional step for devices that have a tamping mechanism for tamping the ground coffee in the portafilter. If the measured level of ground coffee in the portafilter reaches the required amount of ground coffee, the control system turns off the motor and notifies the user, for example, on the coffee grinder display screen, that the required amount of ground coffee is available in the portafilter (step 119).

[0037] The control system is also configured to subsequently determine whether the accumulated amount of ground coffee equals the required amount of ground coffee (step 120). If the accumulated amount of ground coffee reaches the required amount of ground coffee, the control system turns off the motor and notifies the user, for example, on the coffee grinder display screen, that the required amount of ground coffee is in the portafilter (step 121). Otherwise, the control system starts the grinder motor for another predetermined period (step 110).

[0038] As a variant or extension of the example described with reference to Figure 1, the control system may be configured to determine the amount of ground coffee during the grinding operation by the coffee grinder motor based on the power consumed by the coffee grinder motor or based on the value of the consumed electrical energy. In this example, the control system is configured to receive voltage measurement results indicating the voltage on the mill motor and the electrical current consumed by the mill motor. The control system is configured to determine, based on a look-up table, an electrical coefficient of the mill motor corresponding to the characteristics of the coffee beans, to compensate for changes in the consumed power depending on the characteristics of the coffee beans. The electrical coefficient may be the motor current coefficient described above.Thus, power consumption can be determined as the product of the mill voltage, the mill's electrical current, and the electrical coefficient. The amount of ground coffee can then be determined by the control system using a lookup table that correlates various power consumption values ​​with the amount of ground coffee. In this example, a constant power consumption over a period of time would indicate that the grinder hopper is empty or blocked.

[0039] For the process 200 shown in Figure 2, the load sensor unit is a motor sensor designed to measure the rotation of the mill motor during the grinding operation. The mill motor will complete a rotation more slowly when grinding hard coffee beans and will complete a rotation more quickly when grinding soft coffee beans. Accordingly, based on the recorded rotation times, the processor can determine the load on the mill motor. The processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the revolutions measured by the motor sensor related to the rotation. The period can be one of a partial revolution of the mill motor (e.g., one tenth, eighth, quarter, or half of a motor revolution), a full revolution of the mill motor, or a plurality of revolutions of the mill motor.

[0040] As shown in Figure 2, the process 200 implemented by the control system begins after power is supplied to the coffee grinder (step 201). The control system keeps the coffee grinder in the off mode (step 202), in which the coffee grinder does not perform the grinding operation until the control system detects a portafilter located at the lower outlet of the coffee grinder (step 203). This step (step 203) is an additional or optional step for devices that have a system for detecting a portafilter. After detecting the portafilter, the control system puts the coffee grinder into the standby mode (step 204), in which the coffee grinder receives input data related to the characteristics of the coffee beans or detects them, and also accepts user input on the desired (or target) amount of ground coffee. The user can also set the desired degree of grinding for the ground coffee beans.In this regard, the control system has a computer memory for storing one or more look-up tables containing information related to various coffee bean profiles and their characteristics (including the operating parameter of the mill motor described above), and has a display screen on which the user can select the coffee beans that have been placed in the hopper.

[0041] The coffee grinder comprises a switch that is configured to activate a grinding operation (step 205) after the required amount of coffee is loaded into the coffee grinder by the user. The coffee grinder has a portafilter sensor for measuring the level of ground coffee in the portafilter, and the control system is configured to determine the level of ground coffee inside the portafilter based on measurements received from the portafilter sensor (step 206). This step (step 206) is an additional or optional step for devices that have a tamping mechanism for tamping the ground coffee in the portafilter. The amount of ground coffee in the portafilter can be determined by measuring the current of the auger motor of the tamping mechanism for tamping the coffee in the portafilter or using the sensor of the tamping mechanism.If the amount of ground coffee in the portafilter meets the required level (step 207), the control system turns off the grinder motor and notifies the user, for example, on the display screen, that the required level of ground coffee in the portafilter has been reached (step 208). Conversely, if the amount of ground coffee in the portafilter is below the required level, the control system turns on the grinder motor to grind the coffee beans in the hopper (step 209). The control system implements proportional-integral-derivative (PID) control of the grinder motor during the grinding operation.

[0042] In one example, a lookup table compares mill motor speed values ​​(which may relate to the C factor) m engine speed and / or to the coefficient C vi-Irotational emf, as described below) with quantities of ground coffee for different coffee bean characteristics. In this regard, it is understood that motor speed can be affected by a number of factors, including the following: a) the torque of an individual motor at the same voltage, the same load, or the same coffee beans (the higher the torque, the higher the speed); b) the supply voltage at the same load or the same coffee beans (the higher the voltage, the higher the speed); c) the hardness of the coffee beans (the softer the coffee beans, the higher the speed). To compensate for differences in motor torque with changes in speed, each individual motor can be tested for its torque value compared to a standard motor. Based on the difference in motor torque values, the motor under test can be assigned a speed coefficient value (i.e., a C coefficient mmotor speed). To compensate for voltage differences with speed changes, the supply voltage range can be divided into small parts n. Each part n is then tested for speed differences under a standard load, and a coefficient C can be generated based on these vi-i rotational emf from 1 to n.

[0043] To determine the actual rotation speed of the mill, the processor is configured to monitor the rotation (full or partial) or rotations of the mill motor and to monitor the time it takes the mill motor to complete one or more revolutions. This determined actual motor speed value is then compared with the mill motor values ​​in a lookup table to determine the corresponding value for the amount of ground coffee. For example, the lookup table correlates the time required for the mill motor to complete a full / partial rotation with the amounts of ground coffee. The control system is configured to update the accumulated amount of ground coffee in accordance with the determined amount of ground coffee corresponding to each determined time value. The mill motor operates until the accumulated amount of ground coffee reaches the required amount of ground coffee.The lookup table corresponding to this example is shown below. As another example, instead of mapping the time required per revolution(s), the lookup table maps the number of revolutions of the grinder motor per second (or the number of revolutions per time period) to the corresponding amount of ground coffee. where m and n are integers greater than zero, θ m is the corresponding characteristic of coffee beans, I mn represents the value of electric current corresponding to the characteristic of coffee beans θ m , and Q mn represents the value of the amount of ground coffee corresponding to I mn In another example, the reference table above could correlate the measured values ​​of the mill motor speed with the amount of ground coffee. The Q value Tthe accumulated amount of ground coffee is the sum of the quantities of ground coffee Q mn (i), produced during the operation of the mill motor in the i-th preset period of time, until the value of the accumulated amount of ground coffee Q T does not reach the required amount of ground coffee Q D The accumulated amount of ground coffee is updated in the computer memory after each iteration.

[0044] In another example, various coffee bean characteristics or mill motor characteristics are associated with corresponding coefficients in the reference table. The coefficients are intended to compensate for the influence of coffee bean characteristics on the determination of the amount of ground coffee. As an example, the coefficients may include a coefficient related to the measured value of the electric current consumed by the mill motor and / or a coefficient related to the time required for the mill motor to complete a full rotation or partial rotation. The coefficients are represented as a percentage value, so that the correction value can be determined based on the amount of ground coffee determined from the main reference table and the coefficient. The calculated amount of ground coffee produced during a predetermined period will be the sum of the amount of ground coffee and the correction value(s).

[0045] For example, if it is necessary to take into account the electric current and the time required for the grinder motor to complete a full / partial rotation, then one can access the computer memory, which stores a first lookup table of coefficients that maps electric current values ​​to corresponding coefficient values, and a second lookup table of coefficients that maps time values ​​to corresponding coefficient values. In this example, the computer memory also stores a main lookup table that maps the values ​​of the ground coffee quantity to the time required for the grinder motor to complete a full / partial rotation, and / or that maps the values ​​of the ground coffee quantity to electric current values. The ground coffee values ​​in the main lookup table represent the basic (uncompensated) values ​​of the coffee quantity.A computer memory device may store more than two lookup tables of coefficients, each based on a corresponding grain characteristic or mill motor parameter / operation. For example, the computer memory device may store a lookup table of coefficients related to the mill motor speed, or a lookup table of coefficients related to the electrical energy, power consumption of the mill motor, and the difference in motor torque (e.g., the motor speed coefficient C). m , as described above) and / or voltage differences (e.g. C coefficient vi-iThe control system determines the electric current consumed by the mill motor using an electric current sensor, as well as the operating time of the mill motor, determined using a timer. The control system is configured to determine, on the basis of one or more of these values, a base value for the amount of ground coffee according to a main reference table and to determine the corresponding coefficients associated with these values ​​according to the coefficient reference tables. The estimated amount of ground coffee can subsequently be determined by adding the value of the amount of ground coffee determined according to the main reference table and the correction values ​​associated with the coefficients determined according to the coefficient reference tables.In a variant of this example, the main lookup table may store corrected (compensated) values ​​of the amount of ground coffee, which already include correction values ​​related to various time values ​​and / or values ​​of the grinder motor rotation speed, and / or values ​​of the electric current, so that the processor can determine the amount of ground coffee based on only one lookup table. In this variant, separate lookup tables may not be provided. Alternatively, in this variant, separate lookup tables of coefficients may be provided for mapping other parameters or characteristics of the coffee bean grinder, which are not covered by the main lookup table, to the values ​​of the corresponding coefficients. The processor is subsequently configured to determine the amount of ground coffee based on the value of the amount of ground coffee from the main lookup table and the coefficients from the lookup table(s) of coefficients.

[0046] A constant motor speed throughout a rotation or partial rotation, as well as a motor speed higher than the average motor speed, indicate that the grinder hopper is empty. In particular, a constant and high motor speed indicates that the motor is not experiencing any resistance / load / friction, which is the case with an empty hopper. On the other hand, a significant decrease in motor speed indicates a blocked hopper. If the control system determines that the grinder is empty or blocked (step 213), the control system turns off the grinder motor and provides a notification to the user, for example on the display screen, that the grinder is empty or blocked (step 215).Furthermore, the accumulated amount of ground coffee is stored in the computer's memory, so that when the grinder is refilled with coffee beans or unlocked, the control system resumes the previous stop from the stored accumulated amount. After this, the grinder returns to standby mode (step 204).

[0047] On the other hand, if the processor determines that the grinder is not empty or blocked, the control system calculates the amount of ground coffee produced during rotation or partial rotation based on the grinder motor speed (step 216). The amount of ground coffee produced during this rotation or partial rotation is added to the accumulated amount of ground coffee stored in the computer memory. The ground coffee produced during this rotation or partial rotation is fed into the portafilter. The time remaining until the desired amount of ground coffee is reached can be updated using the following equation: where:M represents the required amount of ground coffee; andm represents the ground coffee produced during the rotation of the mill motor in period t.

[0048] The control system is configured to subsequently determine the level of ground coffee in the portafilter (step 217). This step (step 217) is an optional or additional step for devices that have a tamping mechanism for compacting the ground coffee in the portafilter. If the measured level of ground coffee in the portafilter reaches the required amount of ground coffee, the control system turns off the motor and notifies the user, for example, on the coffee grinder display screen, that the required amount of ground coffee is in the portafilter (step 219).

[0049] The control system is also configured to subsequently determine whether the accumulated amount of ground coffee equals the required amount of ground coffee (step 120). If the accumulated amount of ground coffee reaches the required amount of ground coffee, the control system turns off the motor and notifies the user, for example, on the coffee grinder display screen, that the required amount of ground coffee is in the portafilter (step 221). Otherwise, the control system starts the grinder motor for another rotation or partial rotation (step 210).

[0050] In another embodiment, the control system may be configured to determine the amount of ground coffee from the coffee grinder based on a combination of two or more of the electric current consumed by the mill motor, the power consumption of the mill motor, and the rotational speed of the mill motor. The steps implemented by the control system in accordance with this other embodiment will be similar to the steps described above with reference to Figures 1 and 2, and will be a combination thereof.

[0051] Figures 3A and 3B show a coffee grinder according to an embodiment of the present invention. The coffee grinder has a hopper 320 for containing coffee beans to be ground, and a mill motor 340 (or internal mill) for grinding the coffee beans in the hopper. The coffee grinder has an outlet channel 330, from which ground coffee produced by a grinding device that grinds the coffee beans in the hopper can be fed into a portafilter.

[0052] A motor speed sensor for a coffee grinder has a sensor component 380, which is located on the static part of the coffee grinder, and reference components 360, which are located on the dynamic part of the coffee grinder, which is a part of the motor. The sensor component 380 on the static part of the coffee grinder is located near the dynamic part. The reference components are rotated by the mill motor relative to the sensor component such that the sensor component can detect the reference component when the reference component is near the sensor component. Then, the motor speed can be determined after receiving a sensor signal that detects the reference component. In another example, the sensor component can be located on the dynamic part of the coffee grinder, while the reference component(s) can be located on the static part of the coffee grinder.

[0053] In the example shown in Figures 3A and 3B, the dynamic part component on which the support components 360 are located is a rotating shaft for driving the mill motor 340. The static part on which the sensor component is mounted is a part of the mill motor housing located near or adjacent to the dynamic part in which the rotating shaft is located. The sensor component 380 is a Hall effect sensor for detecting a magnetic field, and the reference components 360 are magnets. The magnets 380 are located at a distance from each other around the axis of rotation of the shaft. In particular, the magnets are located on opposite sides of the rotating shaft, spaced 180° apart from each other. The use of two magnets makes it possible to detect half a revolution of the mill motor. In another example, only one magnet can be provided, with which a full revolution can be detected.In other examples, there may be more than two magnets on the shaft or dynamic part of the grinder.

[0054] In another embodiment, the motor sensor may comprise an optical switch or photosensor as the sensor component and an optical film as the reference component. In this embodiment, the optical switch is configured to generate an output signal when the reference component is within the optical switch's line of sight. Specifically, when the mill motor rotates, a line of sight will exist between the sensor component and the reference component. The motor speed can then be determined based on the output signals generated by the optical switch.

[0055] The various embodiments of the present invention described above have been presented by way of example only and not by way of limitation. It will be apparent to those skilled in the art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. The present invention is not intended to be limited by any of the exemplary embodiments described above.

Claims

1. A control system for a coffee grinder comprising a hopper for containing coffee beans, configured to dispense ground coffee, and a mill motor for grinding the coffee beans contained in the hopper, wherein the control system comprises: a load sensor unit for determining at least one operating parameter of a mill motor during a grinding operation in which coffee beans in a hopper are ground by a mill motor to produce ground coffee, wherein the operating parameter of the mill motor is related to a load on the mill motor during the grinding operation; and a processor configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on at least an operating parameter of the mill motor received from the load sensor unit.

2. The control system according to paragraph 1, wherein the operating parameter of the mill motor includes an electric current or electric power for driving the mill during the grinding operation, and the load sensor unit includes an electric sensor for measuring the electric current driving the mill motor; and in which the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the amount of electric current or electric power measured by the sensor over a period of time.

3. The control system according to paragraph 1 or 2, wherein the operating parameter of the mill motor includes the rotational speed of the mill motor during the grinding operation, and the load sensor unit includes a frequency sensor for measuring the rotational speed of the mill motor; and wherein the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the frequency measured by the frequency sensor for at least one rotation of the mill motor.

4. The control system according to paragraph 1 or 2, wherein the operating parameter of the mill motor includes the rotational speed of the mill motor during the grinding operation, and the load sensor unit includes a frequency sensor for measuring the rotational speed of the mill motor; and in which the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the frequency measured by the frequency sensor, the motor frequency factor and the voltage factor.

5. The control system according to any of paragraphs 1-4, wherein the operating parameter of the mill motor includes the time required to complete a full or partial rotation of the mill motor during the grinding operation, and the load sensor unit comprises a sensor for measuring the rotation of the mill motor; and in which the processor is configured to determine the amount of ground coffee dispensed from the hopper during the grinding operation based on the time measured by the sensor for measuring the rotation of the mill motor.

6. A control system according to any one of paragraphs 3-5, in which the sensor comprises a sensor component that is located on one of the dynamic part or the static part of the coffee grinder, and a reference component that is located on the other of the dynamic part or the static part of the coffee grinder, for determining the rotation speed of the motor or time in response to detection by the sensor component of the reference component.

7. The control system of claim 6, wherein the sensor component is a Hall effect sensor and the reference component is a magnet.

8. The control system of claim 6, wherein the sensor component is an optical switch or a photosensor, and the reference component is an optical film.

9. A control system according to any one of claims 6 to 8, wherein the sensor comprises a plurality of spaced apart sensor components and / or a plurality of spaced apart reference components for detecting a partial rotation of the mill motor.

10. The control system according to any of paragraphs 1-9, in which the amount of ground coffee dispensed from the hopper during the grinding operation is determined by the processor during the grinding operation; and the processor is additionally configured to: determining the value of the accumulated amount of ground coffee based on a plurality of amounts of ground coffee determined during the grinding operation, wherein each determined amount of ground coffee relates to a corresponding grinding period.

11. The control system according to paragraph 8, in which the processor is further configured to: receiving user input relating to the required amount of ground coffee; stopping the grinding operation when it is determined that the accumulated amount of ground coffee has reached the required amount of ground coffee.

12. The control system according to paragraph 10 or 11, in which the processor is further configured to: in response to determining that the load on the grinder motor is changing, continue updating the accumulated amount of ground coffee.

13. A control system according to any one of paragraphs 10-12, in which the processor is further configured to: in response to determining that the load on the grinder motor is constant, stop the grinding operation and stop updating the accumulated amount of ground coffee value.

14. The control system of claim 13, wherein the processor is further configured to display on the electrical display device of the coffee grinder a message that the hopper is empty or blocked, in response to determining that the load on the mill motor is constant.

15. A control system according to any one of paragraphs 1-14, in which the processor is further configured to: determining the amount of ground coffee dispensed from the bin during a grinding operation in response to at least one characteristic of the coffee beans in the bin.

16. A coffee grinder containing: a hopper for placing coffee beans, designed with the possibility of dispensing ground coffee; a mill motor for grinding coffee beans contained in the hopper; and a control system according to any one of claims 1-15 for determining the amount of ground coffee dispensed from the hopper during the grinding operation by the mill motor, wherein the control system is configured to control the mill motor in response to the production of a determined amount of ground coffee.

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