COFFEE GRINDER-DOSER APPARATUS WITH INDEPENDENT FORK AND WEIGHING DEVICE WITH FEEDBACK

Abstract

Electronic grinder-doser apparatus of the type with weight control or grind-by-weight, intended to grind and precisely dose coffee in beans dispensing the ground product in a filter-holding bowl for espresso coffee. Implemented is a dose compensated weighing system, of the multi-cycle and feedback type at every cycle, carried out by a device with a load cell and specific execution programs. The cell is interposed between the machine body and a base shaped in such a way as to integrate the centering fork of the bowl, making the hooking independent. The specific programs execute each grinding and dispensing cycle with a double weighing and automatic calibration, according to an Algorithm A comprising 4 steps (AF1-AF4) and a Filtering Algorithm B. The apparatus is suitable for professional daily use and helps the operator, by automatically calibrating during use.

Claims

1. Grinder-doser apparatus (10) of the type with weight control, intended to grind and precisely dose coffee in beans (300) dispensing the ground product in a filter-holding bowl (200) for espresso coffee, which integrates a weighing device with a load cell for the real-time weighing of the dose during dispensing and for automatically controlling the actually dispensed dose weight in grams, with the motor off; with consequent automatic calibration; said grinder-doser apparatus (10) consisting of an upper part (101) and of a lower part acting as a base (102), wherein between them a load cell (103) is interposed, which progressively detects the weight loss of said upper part (101); said upper part (101) comprising: a machine body (105) with the conventional grinding means like the grinders (118) and the motor (119), a front dispensing compartment (107) which is crossed by a chute duct (120) the front end of which is the dispensing spout (109), a screen (108) acting as a control panel, a cone-shaped container (110) for the roasted coffee beans, which is placed above said machine body (105); said grinder-doser apparatus (10), of the electromechanical type with electronic control, being equipped with a logic control unit (106), which is connected, at least for data transfer, to said screen (108), to said motor (19) and to said cell (103); said load cell (103) and said logic unit (106) being intended to dispense the desired dose by stopping the motor before reaching the required weight (PR), that is to say, taking into account an amount of ground coffee that is dispensed anyway after the motor has been switched off, which is conventionally called residual amount (QV); said grinder-doser apparatus (10) being characterised in that the hooking (205) of the filter-holding bowl (200) is independent of the weighing since it is constrained to said base (102), below the cell (103), said base (102) being shaped in such a way as to integrate the supporting and centering fork (113) making it independent of said upper part (101), which has a barycentric arrangement configuration on the detection plane (104) of the cell (103), that is to say, with the vertical axis (122) passing through the cone (110), the grinders (118) and the motor (119), which is of the barycentric type.

2. Grinder-doser apparatus (10) according to claim 1, characterised in that it integrates a weighing device (116) which comprises said load cell (103) and execution programs (117) loaded in said logic control unit (106), such as to execute at every grinding cycle a double weighing with continuous feedback, according to a first algorithm, called Execution Algorithm A, and a second algorithm called Filtering Algorithm; said Algorithm A providing at least one first real-time weighing, that is to say, during grinding, wherein the motor is stopped in advance with respect to the required weight in such a way as to consider a variable amount of product that corresponds to said residual amount (QV) and is automatically modifiable at every cycle, and a second weighing with the motor off to check the actually dispensed dose and the variance with respect to the required dose weight in grams, with consequent automatic calibration of the weight value corresponding to motor downtime (PF), as in said first weighing; said Algorithm B being active at least during said first weighing in such a way as to filter the mechanical vibrations of the motor and/or other disturbances.

3. Grinder-doser apparatus (10) according to claim 2, characterised in that said Algorithm A provides the following 4 execution steps (AF1-AF4), in sequence: the first step (AF1) is of calculation and execution of the Motor Downtime Weight (PF), with real-time weighing, that is to say, with the motor on, wherein said residual amount (QV) is variable since it is re-set at every cycle depending on the feedback (AF2-AF4):
PF=PR?QV; the second step (AF2) is of check of the actually Dispensed Weight (PE):
PE detected with the motor off; the third step (AF3) is of calculation of the Variance (SC):
SC=PE?PR the fourth step (AF4) is of calculation and re-setting of the new Residual Amount (QV) to be used in the first step (AF1) of the following cycle, depending on said variance (SC) and compensated for by a Correction Factor (FC) of 0.35 considering a tolerance of +/?20%:
QV of following cycle=QV+SC*FC.

4. Grinder-doser apparatus (10) according to claim 3, characterised in that said Algorithm B provides at least one of the following filtering operations (B1, B2): mean value filtering (B1) where one calculates a mean value of the values acquired in a given period of time, like an arithmetic mean, and/or low-pass filtering (B2) where one eliminates or diminishes the value of the mechanical oscillations from a given frequency onwards, like a cut-of frequency.

5. Real-time weighing system with continuous feedback for automatic calibration, of the multi-cycle type, for a grinder-doser apparatus (10) of the type with weight control, intended to grind and precisely dose coffee in beans (300) dispensing the ground product in a filter-holding bowl (200) for espresso coffee; said grinder-doser apparatus (10) consisting of an upper part (101) and of a lower part acting as a base with an electronic load cell (103) which is interposed between said parts; said upper part (101) comprising a logic control unit (106), a machine body (105) with the grinding and dispensing means, and with, above, the cone-shaped container (110) for coffee (300); and wherein said logic control unit (106) is connected to said cell (103) in such a way as to constitute an electronic weighing device integrated in said grinder-doser apparatus (10); said weighing system being characterised in that the hooking (205) of said filter-holding bowl (200) to the apparatus (10) occurs independently of the weighing, by constraining it below the load cell (103) by means of said base (102) which is shaped and integrates the centering fork (113); and wherein the weighing device (116) comprises said cell (103) and execution programs (117) loaded in said logic control unit (106), such as to execute at every cycle a double weighing with continuous feedback, in the following way: the operator constrains a filter-holding bowl (200) to the centering fork that is independent (113), then, upon pressing the start button, the motor (119) activates the grinders, which begin to dispense the coffee powder; said weighing device (116) instantaneously activates a first real-time weighing that checks the weight of the dispensing continuously, then the motor stops upon reaching the downtime weight (PF), that is to say, the stop weight, corresponding to the required dose (PR) from which the variable amount of product dispensed after switch-off, which is also called residual amount (QV), has been opportunely subtracted; the operator removes said filter-holding bowl (200) and the apparatus starts said feedback by controlling the actually dispensed weight (PE) and, if there is said variance (SC) between the required and the dispensed dose weight in grams, one activates re-calculation with compensation and automatic calibration, that is to say, the re-setting for the following cycle of said residual amount (QV) and, as a consequence, of said downtime weight (PF).

6. Real-time weighing system with continuous feedback, according to claim 5, characterised in that in said execution programs (117) there is a first algorithm, called Algorithm A, which provides the following 4 execution steps (AF1-AF4) in sequence: the first step (AF1) is of calculation and execution of the Motor Downtime Weight (PF), where PF=PR?QV; the second step (AF2) is of check of the actually Dispensed Weight (PE) with the motor off; the third step (AF3) is of calculation of the Variance (SC), where SC=PE?PR; the fourth step (AF4) is of calculation and re-setting of the new Residual Amount (QV) to be used in the first step (AF1) of the following cycle, depending on said variance (SC) and compensated for by a Correction Factor (FC) of 0.35 considering a tolerance of +/?20%, wherein the value QV of the following cycle=QV+SC*FC; and wherein, said execution programs (117) also include a second algorithm, called Algorithm B, which is active at least during weighing with the grinders in operation as in said first step (AF1) of the Algorithm A, in such a way as to filter the mechanical vibrations of the motor or other disturbances, by performing at least one of the following filtering operations (B1, B2): mean value filtering (B1) where one calculates a mean value of the values acquired in a given period of time, like an arithmetic mean, and/or low-pass filtering (B2) where one eliminates or diminishes the value of the mechanical oscillations from a given frequency onwards, like a cut-off frequency.

7. Electronic weighing device (116) for a coffee grinder-doser apparatus (10) of the electronic type with weight control intended to grind and precisely dose coffee in beans (300) dispensing the ground product in a filter-holding bowl (200) for espresso coffee; said weighing device (116) being characterised in that it comprises an electronic load cell (103) with a horizontal load plane (104) and with execution programs (117) loaded in the logic control unit (106) of the apparatus (10), in such a way as to execute at every cycle a double weighing with continuous feedback; said cell (103) being placed below a machine body (105) without the supporting and centering fork (113) of said bowl (200), in such a way as to detect the weight loss in a barycentric and independent way with respect to it (200); and wherein said execution programs (117) comprise a first algorithm, called Algorithm A, which for each cycle provides the following 4 execution steps (AF1-AF4), in sequence: the first step (AF1) is of calculation and execution of the Motor Downtime Weight (PF), with real-time weighing, that is to say, with the motor in operation, wherein said residual amount (QV) is variable since it is re-set at every cycle depending on the feedback (AF2-AF4):
PF=PR?QV; the second step (AF2) is of check of the actually Dispensed Weight (PE):
PE detected with the motor off; the third step (AF3) is of calculation of the Variance (SC):
SC=PE?PR; the fourth step (AF4) is of calculation and re-setting of the new Residual Amount (QV) to be used in the first step (AF1) of the following cycle, depending on said variance (SC) and compensated for by a Correction Factor (FC) of 0.35 considering a tolerance of +/?20%:
QV of following cycle=QV+SC*FC; and wherein said execution programs (117) also comprise a second algorithm, called Algorithm B, which is active at least during said real-time weighing (AF1) in such a way as to filter the mechanical vibrations of the motor and/or other disturbances, providing at least one of the following filtering operations (B1, B2): mean value filtering (B1) where one calculates a mean value of the values acquired in a given period of time, like an arithmetic mean; low-pass filtering (B2) where one eliminates or diminishes the values of the mechanical oscillations from a given frequency onwards, like a cut-off frequency.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0051] FIG. 1 is a side view of a conventional electronic grinder-doser apparatus of the grind-by-time type, which is also provided with a continuous and automatic calibration system by means of a load cell positioned between the base and the machine body in such a way as to progressively detect the weight loss of the coffee in beans; the upper part of the apparatus, comprising said machine body, and the lower part comprising the base, are schematically delimited by a dotted line.

[0052] FIG. 2 is a side view of an electronic grinder-doser apparatus of the grind-by-weight type, according to the present invention, wherein the supporting and centering fork of the bowl is made independent of the machine body and of the weighing being coupled with a base that is shaped to such purpose, and with specific execution programs included in the logic control unit of the apparatus. The upper part and the lower part of the apparatus are schematically delimited by a dotted line; obvious and conventional components for the operation of the proposed system, such as wirings, transformers, connectors, push-buttons, etc., are not shown.

[0053] FIGS. 3a and 3b represent the apparatus disclosed by the invention, as in the previous figure, respectively in a side view with the bowl hooked (FIG. 3a) wherein the dotted area refers to the enlarged detail of the dispenser, as in the following figure (FIG. 3b), highlighting the path of the coffee powder between the grinder and the centering fork of the filter-holding bowl, with reference to said residual amount as well.

DETAILED DESCRIPTION OF THE INVENTION

[0054] With reference to the drawings (FIGS. 2, 3a, 3b), the proposed invention relates to an electronic grinder-doser apparatus (10) of the type with weight control, called grind-by-weight, which is intended to grind and precisely dose coffee in beans (300) dispensing the ground product (301) in a filter-holding bowl (200, 202) for espresso coffee. Said apparatus (10) integrates an advantageous weighing device (116) that comprises a load cell (103) and specific execution programs (117), said cell being interposed between the machine body (105) and a particular base (102) shaped in such a way as to integrate the centering fork (113) and make the hooking of said bowl (200) independent. The invention allows to automatically dispense in the filter, for each dose, the always exact dose in grams of coffee powder (301).

[0055] In particular, at each grinding and dispensing cycle the product is weighed at least twice: the first time directly during dispensing, in such a way as to stop the motor also keeping into account the variable quantity of product that is dispensed anyway after the motor has been switched off, which is conventionally called residual amount (QV), and a second time at the end of dispensing, that is to say, with the motor off, detecting the actually dispensed weight (PE) of the dose. Such values (QV, PE) are thus automatically re-calculated and consequently re-set by the apparatus (10), for the following cycle, on the basis of the variance (SC) detected with respect to the required weight (PR). Said weighings and the consequent automatic calibration are advantageously managed by means of said specific execution programs (117), which are preferably included in the logic unit (106) that simultaneously checks all the electromechanical and electronic components of the apparatus, among which the motor and the load cell, which are interconnected with each other.

[0056] The grinder-doser apparatus (10) disclosed by the invention (FIG. 2) is of the electromechanical type with electronic control, conventionally called electronic grinder-doser, which integrates a weighing device of the electronic type with at least one load cell (103) which is intended to autonomously and precisely detect the exact weight loss of the mass resting on its load plane. Structurally, the apparatus (10) is made up of two main parts (101, 102), that is to say, an upper part (101) of the complex type and a lower part of the single-piece type formed by a shaped base (102), wherein said cell is interposed between them in such a way as to progressively detect the variation in weight of said upper part (101), during and after dispensing, in a substantially barycentric way and without being affected by impacts or by any external stress.

[0057] In more detail as to the realization of said upper part (101), the latter comprises a main body called machine body (105) which comprises the conventional grinding means such as the motor (119), at least one grinder (118), the logic control unit (106) and is also connected to a chute duct (120) that allows for the transit of the ground coffee powder (301) through a dispensing compartment (107) that is frontally joined to said machine body and from which the end thereof exits, like a spout (109) for the dispensing in the filter-holding bowl (200, 202). Preferably, said dispensing compartment comprises at the front a touchscreen (108), acting as a control panel, which is thus connected to said logic control unit (106). Above said machine body (105), in correspondence of the neck (111), a cone-shaped container (110) for the roasted coffee beans (300) is conventionally fastened. For the purposes of the invention, said upper part (101) does not have the conventional supporting and centering fork of the filter-holding bowl (200), which is thus made independent of weighing, being released from the machine body (105) and from the load plane (104) of the cell (103) (FIGS. 2, 3a, 3b). The present description does not contain the conventional elements that are included in the apparatus in any case such as: the electrical wirings, the transformers, the electronic connections, the mechanical fastenings, the structural casing.

[0058] It should be noted that said load plane (104) corresponds to the bottom of the machine body (105), it being structurally integral with it; the weight resting on said load plane, and which thus rests on the oscillating side of the cell, corresponds exclusively to the weight of said upper part (101) which is characterised by a barycentric arrangement on its vertical axis (122) passing through the cone (110), the grinders (118) and the motor (119), said weight being substantially central, that is to say, not overhanging, with respect to said plane (104), and is not affected by the hooking and/or release of said bowl (200). The centering fork of the bowl (113), in fact, is obtained in an integral way from said shaped base (102, 103-115) and is constrained to the fixed side of the cell, that is to say, below it. Such a solution (FIGS. 2, 3a) thus involves the hooking (205) of the bowl to a fork (113) that is advantageously integral with the lower part of the apparatus (102). In the known solutions (FIG. 1), on the other hand, the hooking (204) is to a fork (112) that is integral with the upper part (100a) of the apparatus, considerably affecting the validity of the weighing or the calibration of the cell; to this purpose, see for example the prior art drawing.

[0059] In more detail as to the realization of said shaped base (102), as disclosed by the invention, it is made up of a portion of base (115) in contact with the support plane (400), which is provided at the front with a protrusion acting as a connector (114) that develops upwards, as a double-bend S-shaped or Z-shaped extension, in such a way as to form in the front end a strong supporting and centering fork (113) for a standard filter-holding bowl (200), reproducing the same hooking configuration and position in use in the professional sector. For example, a filter-holding bowl (200) for espresso coffee bar machines (201), comprising a horizontal handle (201) wherein the small bowl containing the filter (202), for one or two doses, is joined at the end, and wherein below it there are the spouts (203) for dispensing espresso coffee into the cup, is suitable for the invention.

[0060] In principle, an electronic weighing means with a horizontal detection plane is used, such as a single point load cell (103), which is intended to precisely detect a weight between 0 and 20 grams measuring variations up to one hundredth of a gram, also considering a high tare weight. Said load cell precisely detects the progressive weight loss of said upper part (101), in correspondence of said load plane (104), making immediately available to said specific execution programs (117), and therefore to the logic control unit (106), at least the exact weighing value in hundredths of a gram. As a non-exhaustive example, a cell of the type marketed by the German company Siemens under the name of Siwarex R Load CellsSp Seriesin the customized configuration for weights lower than 0.1 Kg and detections up to one hundredth of a gram is suitable for the invention.

[0061] It is also observed that the path (121) of the ground powder (301) substantially corresponds to its trajectory from said grinder (118) to the filter in the small bowl (202), and said residual amount (QV) primarily depends on it. Said amount is linked to the inertia of the motor and of the grinder, but above all depends on geometric factors of shape and length of said chute (120), in which temporary accumulation is possible, said accumulation being not constant; therefore, it is necessary to re-calibrate said residual amount every time on the basis of the contextual conditions of the apparatus (10) and of the coffee (301) in transit along said path, continuously maintaining the dispensed dose weight in grams as close as possible to the required one (FIG. 3b).

[0062] To this purpose, an electronic weighing device (116) is disclosed, which is integrated in the apparatus (10) and consists of the load cell (103) and of specific execution programs (117) (FIG. 2), in such a way as to automatically detect the weight of each dose during grinding, to stop the motor in such a way as to obtain the desired dose, and at the end of dispensing, too, to control every time the actual dose weight in grams dispensed and consequently re-program the logic unit of the apparatus (106), like automatic calibration. Basically, the proposed weighing device (116, 117, 103) allows to carry out dispensing according to a compensated dose weighing system, of the multi-cycle and feedback type every time, wherein at every cycle of grinding and dispensing of the dose there are two weighings, one with the motor on and one with the motor off with the consequent automatic calibration of the set data, like feedback.

[0063] The effectiveness of the proposed solution (10, 116) is particularly connected to the fact that said weighings refer to a substantially barycentric arrangement of the masses resting on the load plane (104) and are not affected by the hooking-release of the bowl (200, 202), which is made independent of the machine body (105) and of the cell (103) by means of said independent fork (113) integral with the base (102), as explained above. In practice, it was observed that in this way one effectively solves the known problem of the incompatibility between the high sensitiveness of detection of the cell and the execution of detection, particularly by eliminating the removable overhanging masses and the consequent stresses and/or accidental impacts.

[0064] Basically, by the proposed weighing device (116, 117, 103) grinding is stopped on the basis of the weight planned for stopping by suitably keeping said residual amount into account, wherein such values are re-set every time depending on the variance detected between the desired dose weight in grams and the actual weight of the dose, in such a way as to consequently compensate for the set values with a correction factor (FC), as explained below. To this purpose, said specific dispensing programs (117) include at least two algorithms: a first algorithm called Algorithm A, which executes said double weighing with automatic calibration, and a second algorithm called Algorithm B that filters the vibrations, and/or any other disturbances, at least during weighing with the motor on, that is to say, simultaneously to said first algorithm.

[0065] In more detail as to said algorithm A, it consists of 4 steps in sequence (AF1-AF4) intended to complete one single grinding and dispensing cycle, automatically re-setting every time the weight value corresponding to the motor downtime (PF) or stop, and the related amount of product that is dispensed anyway after the motor has been switched off, which is also called residual amount (QV); such weights (PF, QV), being re-calculated on the basis of the variance (SC) detected between the required weight (PR) and the actually dispensed weight (PE), like a compensation, with a particular correction factor (FC). In more detail as to the steps, the following execution is provided in sequence: [0066] first step (AF1): first weighing, with the grinders in operation, with switching-off of the motor upon reaching the motor downtime weight (PF), defined on the basis of the required weight (PR) and of the residual amount (QV) being (PF)=(PR)?(QV); [0067] second step (AF2): second weighing, with the motor off, to check the actually dispensed weight (PE); [0068] third step (AF3): calculation of the variance (SC), being (SC)=(PE)?(PR); [0069] fourth step (AF4): calculation and re-setting of the new residual amount for the following cycle (QVn), compensating for said variance (SC) with a correction factor (FC) preferably of 35/100, that is to say, 0.35 being (QVn)=(QV)+(SC)*(FC).

[0070] Said Algorithm B provides that at least during said first step (AF1), in which the load cell (103) detects with the motor on the weight loss of said upper part (101, 300), the motor's vibrations, or other disturbances, are automatically filtered by means of digital filters that can be, alternatively or jointly, of the type called mean value and/or of the type called low-pass. In more detail, the load cell (103) converts the detected weight into an analogue signal, which in its turn is then transformed into a digital number by means of an analogue-digital converter, generally called AD converter, said digital number can be subject to variations caused by fluctuations of the supply of the electronic components and/or by mechanical oscillations that generate a series of weight variations, which alternate between positive and negative. In order to eliminate these problems, therefore, the invention proposes to digitally filter said vibrations and/or oscillations by applying said mean value and/or low-pass filters.

[0071] In more detail, said Algorithm B provides two filtering operations (B1, B2), which are carried out alternatively (B1 or B2) or jointly (B1 and B2) with respect to each other, being: [0072] a first filtering called mean value filtering (B1), where one calculates a mean value of the values acquired in a given period of time, for example with an arithmetic mean; [0073] a second filtering called low-pass filtering (B2), where one eliminates or diminishes the values of said mechanical oscillations from a given frequency onwards, which is also called a cut-off frequency. It can be seen that the frequency (f) is equal to the opposite of the oscillating period (T), that is to say, f=1/T, where this oscillation period corresponds to the time between two variations of the same sign, both positive or both negative.

EXAMPLE

[0074] A practical example is provided below of how the above-described grinder-doser apparatus (10), by means of the proposed weighing device (116), automatically performs each dispensing cycle with real-time weighing and feedback, according to said Algorithm A. For the purpose of explanation and to facilitate understanding, 5 consequential cycles are pointed out, of which the first cycle or Cycle 1 corresponds to the initial setting where the required weight (PR) of the single dose is established, which is of 7.0 g and wherein the first value corresponding to the residual amount (QV1) of 0.5 g is initially supposed, to define the first value corresponding to the motor downtime weight (PF1); such values (QV, PF) being every time automatically re-set for the following cycle, as exemplified below:

CYCLE 1

[0075] AF1) Calculation and execution of the motor downtime weight: PF1=PR?QV1=7.0 g?0.5 g=6.5 g [0076] AF2) Start of feedback with check of dispensed weight: PE1=7.6 g [0077] AF3) Calculation of the variance: SC1=PE1?PR=7.6 g?7.0 g=0.6 g [0078] AF4) Calculation and re-setting of the following residual amount: QV2=QV1+SC1*FC=0.5 g+0.6 g*0.35=0.5 g+0.21 g=0.71 g

CYCLE 2

[0079] PF2=PR?QV2=7.0 g?0.71 g=6.29 g [0080] PE2=7.4 g [0081] SC2=PE2?PR=7.4 g?7.0 g=0.4 g [0082] QV3=QV2+SC2*FC=0.71 g+0.4 g*0.35=0.71 g+0.14 g=0.85 g

CYCLE 3

[0083] PF3=PR?QV3=7.0 g?0.85 g=6.15 g [0084] PE3=7.0 g [0085] SC3=PE3?PR=7.0 g?7.0 g=0 g=exact weight [0086] QV4=?QV3+SC3*FC=0.85 g+0 g*0.35=0.85 g

CYCLE 4

[0087] PF4=PR?QV4=7.0 g?0.85 g=6.15 g [0088] PFA=6.5 g [0089] SC4=PE4?PR=6.5 g?7.0 g=?0.5 g [0090] QV5=QV4+SC4*FC=0.85 g+(?0.5 g*0.35)=0.85 g?0.175 g=0.675 g

CYCLE 5

[0091] PF5=PR?QV5=7.0 g?0.675 g=?6.325 g [0092] PE5=7.0 g [0093] SC5=PE5?PR=7.0 g?7.0 g=0 g=exact weight [0094] QV6=QV5+SC5*FC=0.675 g+g*0.35)=0.675 g

[0095] It can be seen that, if the dispensed weight (PE) is lower than the required weight (PR), the residual amount (QV) of the following cycle will thus be lower, in such a way that the downtime weight (PF) will be greater; vice versa, if the dispensed weight is greater, said residual amount will be increased, in such a way that the motor at the following dispensing stops at a lower weight. Said correction factor (FC) is statistically determined in such a way as to compensate for the excessive variances due to accidental causes; therefore, it was experimentally verified that a value of about 0.35 is effective in the use provided by the invention.

[0096] To conclude, thanks to the structural configuration with an independent filter-holding bowl, preferably integrated into the base of the apparatus, the cell is protected from the known problems of impacts or torsions due to the continuous engagement and release of the filter-holding bowl, which sometimes decalibrate and/or damage the sensitiveness of the cell itself. Therefore, it is possible to progressively detect weight (AF1) during grinding, that is to say, in real time, and it is also possible to perform a following weighing (AF2) of check with the motor off without handling the apparatus, to then calculate (AF3) and consequently and automatically re-set (AF4) the setting values in such a way as to get closer and closer to the desired dose weight in grams, like feedback. Basically, the cell (103) detects by difference the progressive weight loss of the mass (101) that rests in a barycentric way on the load plane (104) and stops the motor upon reaching the set nominal weight from which the amount of coffee dispensed by inertia after the grinders have been stopped, that is to say, said residual amount (QV), is opportunely subtracted, which is experimentally determined every time as explained above by means of a correction factor (FC); then, with the motor off, the same cell checks the actually dispensed weight (PE) and consequently executes said feedback, wherein, in case there is a variance (SC), that is to say, discordance, between the required dose and the dispensed dose because of interventions or external factors, such as the adjustment of grinding, air humidity or other variables, by means of automatic processing it modifies said residual amount for the following cycle.

[0097] Therefore, a complete grinding cycle with feedback performed by the apparatus (10) according to the invention, in daily professional use, is as follows: the operator constrains a filter-holding bowl (200) to the independent centering fork (113) then, by pushing the motor's start button (119), the operator activates the grinders that begin to dispense the coffee powder, the system (10, 116) instantaneously activates said real-time weighing that continuously checks the weight of the dispensing. The motor stops upon reaching the downtime weight (PF), which corresponds to the required dose (PR) from which said residual amount (QV) was opportunely subtracted; then the grinder-doser apparatus continues to dispense said residual amount, thus obtaining the required dose. The operator removes the filter-holding bowl and the apparatus starts said feedback by controlling the actually dispensed weight (PE) and, if there is said variance (SC) between the required dose weight in grams and the dispensed dose weight in grams, re-calculation is activated with compensation and automatic calibration, that is to say, the re-setting for the following cycle of said downtime weight (PF) and residual amount (QV).

[0098] Therefore, in practice it was observed that the proposed solution efficiently simplifies the operator's professional activity, reducing the operator's physical and mental fatigue while providing a greater quality of the service as well, the grinder-doser apparatus (10) being constantly calibrated in such a way as to automatically stop grinding and obtain the desired dose with precision.

REFERENCE

[0099] (10) electronic grinder-doser apparatus for coffee in beans of the type called grind-by-weight, as provided by the present invention; [0100] (100a) upper part of the apparatus, as in the known prior art; [0101] (100b) base, in contact with the support plane and corresponding to the lower part of the apparatus, as in the known prior art; [0102] (101) upper part of the apparatus, according to the invention; [0103] (102) shaped base constituting the lower part of the apparatus, according to the invention; [0104] (103) load cell; [0105] (104) load plane resting on the cell, corresponding to the bottom of the machine body; [0106] (105) machine body; [0107] (106) logic control unit of the apparatus and of the cell; [0108] (107) dispensing compartment; [0109] (108) touchscreen acting as a control panel; [0110] (109) spout for dispensing the ground coffee in the filter; [0111] (110) cone-shaped container for the roasted coffee beans; [0112] (111) neck; [0113] (112) conventional supporting and centering fork of the bowl; [0114] (113) independent fork with respect to the machine body, base portion acting as a supporting and centering element of the bowl; [0115] (114) base portion acting as a connector; [0116] (115) base portion in contact with the support plane, below the cell; [0117] (116) weighing device, according to the invention; [0118] (117) specific weighing execution programs, including at least: one first dispensing algorithm and a second filtering algorithm; [0119] (118) grinder; [0120] (119) motor; [0121] (120) chute duct; [0122] (121) path of the ground powder between the grinder and the bowl; [0123] (122) vertical axis of the barycentric type, passing through the cone, the grinders, the motor and the load plane of the cell; [0124] (200) filter-holding bowl, completely assembled; [0125] (201) handle; [0126] (202) small bowl containing the filter; [0127] (203) spouts for dispensing espresso coffee into the cup; [0128] (204) hooking to the fork in the upper part of the apparatus, as in the known prior art; [0129] (205) hooking to the fork in the lower part of the apparatus, independently of the weighing, as provided by the present invention; [0130] (300) roasted coffee beans; [0131] (301) ground coffee; [0132] (400) support plane; [0133] (AF) Steps of execution of the Algorithm A, which are in sequence: (AF1) Calculation and execution of the motor downtime weight, (AF2) Start of feedback with check of the dispensed weight, (AF3) Calculation of the variance, (AF4) Calculation and re-setting of the following residual amount; [0134] (B1, B2) Filtering operations of the Algorithm B, which are alternatively or jointly: mean value filtering (B1) and/or low-pass filtering (32); [0135] (FC) Correction factor; [0136] (PE) Dispensed weight; [0137] (PF) Motor downtime weight; [0138] (PR) Required weight for the dose, it is a fixed value and corresponds to the desired dose weight in grams, it is established by the operator by means of the control panel; [0139] (SC) Variance; [0140] (QV) Residual amount, it is the amount of product dispensed after the motor has been switched off.