Control method for controlling the current dispensing cycle of a coffee machine

Abstract

The invention provides a control method for controlling a current dispensing cycle of a coffee machine comprising an electronic controller, a brewing pump and a brewing unit having a containing chamber for a quantity of coffee powder, wherein the current dispensing cycle comprises a dispensing step and a possible preliminary step of wetting the quantity of coffee powder, in which preliminary step no dispensing has yet taken place, the control method providing that the electronic controller controls the dispensing speed of the entire dispensing step of the current dispensing cycle by dividing the brewing pump by a control algorithm, the control algorithm obtaining parameters calculated from stored dispensing data of a dispensing step of a dispensing cycle that only precedes the current dispensing cycle.

Description

DETAILED DESCRIPTION

[0001] The invention relates to a control method for controlling a current dispensing cycle of a coffee machine and to a coffee machine implementing said method.

[0002] Specifically, the control method of the present invention is applied to a coffee machine including a brewing pump and an electronic controller for controlling the brewing pump.

[0003] The organoleptic quality of a coffee beverage depends substantially on how the dispensing cycle is performed, in particular with regard to the brewing of the coffee grounds.

[0004] In particular, the dispensing speed of the beverage itself has a large influence on the sensory qualities of the extraction.

[0005] The optimal extraction cycle for a coffee machine depends on the type of coffee beverage, such as espresso (both short and long) or Americano, the particle size of the coffee grounds used, the type of coffee used and the state of degradation of the machine itself.

[0006] Some control methods for controlling the current dispensing cycle of a coffee machine are known in the prior art, which are based on dividing the brewing pump by brewing the coffee powder with hot water in periodic intervals, wherein each periodic interval comprises a pump activation period and a pump deactivation period.

[0007] Some of these current dispensing control methods are based on partitioning of the brew pump that is preset in the coffee machine before it is available for sale.

[0008] In this case, the coffee beverage is extracted in a disadvantageous manner which is neither optimized with respect to the different types of brewing, particle sizes and coffee used, nor with respect to degraded states of operation of the coffee machine.

[0009] On the other hand, other control methods are based on the partitioning of the brewing pump, where some brewing parameters are acquired during a first part of the dispensing step and processed to optimize a second part of the dispensing step.

[0010] These latter control methods therefore do not allow an optimization of the entire dispensing step, since it disadvantageously requires optimizing the second part of the dispensing step in the first part of the dispensing step.

[0011] Therefore, if the allocation step is very short, only a small portion is optimally executed.

[0012] One object of the present invention is to provide a control method for controlling the current dispensing cycle of a coffee machine which solves the aforementioned problems of the prior art and in particular allows an optimal extraction of the coffee beverage during the duration of the dispensing step.

[0013] Another object of the invention is to provide a control method for controlling a current dispensing cycle which has improved performance with respect to that known in the prior art.

[0014] Another object of the present invention is to provide a control method for controlling the current dispensing cycle which allows an optimized dispensing of a coffee beverage regardless of the type of beverage, the type of particle size of the coffee powder and the state of wear of the coffee machine used.

[0015] Yet another object of the present invention is to provide a control method for controlling the current dispensing cycle which allows an optimized dispensing of the coffee beverage regardless of environmental variations.

[0016] Not least, an object of the present invention is also to provide a coffee machine capable of providing an improved dispensing quality with respect to those known in the prior art.

[0017] The technical task and these and other objects are achieved according to the invention by providing a control method for controlling a current dispensing cycle of a coffee machine comprising an electronic controller, a brewing pump and a brewing unit having a containing chamber for a quantity of coffee powder, wherein the current dispensing cycle comprises a dispensing step and a possible preliminary step of wetting said quantity of coffee powder, in which preliminary step no dispensing has yet taken place, the control method being characterized in that the electronic controller controls the dispensing speed of the entire dispensing step of the current dispensing cycle by dividing said brewing pump by a control algorithm which obtains parameters calculated from stored dispensing data of dispensing steps of dispensing cycles which immediately precede the current dispensing cycle.

[0018] In particular, by means of the control algorithm, the controller is able to adapt the dispensing speed over time to an optimal reference profile.Preferably, the control algorithm also acquires a data sheet representative of the amount of coffee powder used to perform the current dispensing cycle.

[0019] Advantageously, when providing a wetting step, the control algorithm also acquires a data sheet representative of the type of wetting used to perform the current dispensing cycle.

[0020] Advantageously, the control algorithm for dividing the brewing pump calculates at least one of the parameters of a periodic control function.

[0021] Specifically, the parameters of the control function include at least one start time value in a period of the function.

[0022] Preferably, the period of the function includes a unique continuous activation time and a unique continuous deactivation time.

[0023] Preferably, the continuous activation time corresponds to activation at rated power of the brewing pump.

[0024] Preferably, once the type of preliminary wetting step and the amount of coffee powder for the current dispensing cycle have been determined, the pump activation time in the current dispensing cycle is directly proportional to the amount of coffee powder for the beverage in the current dispensing cycle and inversely proportional to the average dispensing speed of previous dispensing cycles weighted based on its division, wherein the previous dispensing cycles were for the same type of wetting and the same amount of powder as the current dispensing cycle.

[0025] Other characteristics of the invention are also defined in the following claims.

[0026] Further characteristics and advantages of the invention will emerge more fully from the description according to a preferred but non-exclusive embodiment of a control method and an automatic coffee machine, illustrated by way of non-limiting example in the accompanying drawings, in which:

[0027] - Figure 1 A flow chart showing a control method according to the present invention is shown;

[0028] - Figure 2 A diagram showing the division of the flow rate of a pump according to the invention is shown.

[0029] The invention relates to a control method for controlling a current dispensing cycle of a coffee machine comprising an electronic controller, a brewing pump and a brewing unit having a receiving chamber with a quantity of coffee grounds.

[0030] In particular, the current dispensing cycle comprises a dispensing step and a possible preliminary wetting step of the amount of coffee powder, during which dispensing has not yet taken place.

[0031] One type of wetting step may provide for recompression of the coffee powder during the waiting time after wetting and before the dispensing step begins, whereas another type of wetting step may not provide for recompression.

[0032] According to the control method of the present invention, the electronic controller controls the dispensing speed of the entire dispensing step of the current dispensing cycle.

[0033] The electronic controller controls the speed by dividing the brew pump by a control algorithm.

[0034] Due to the division of the pump, the dispensing rate of the beverage is maintained at a set point value or in a predetermined neighborhood of the set point value.

[0035] The brewing pump is divided to drive the pump intermittently by implementing a periodic cycle of pump activation time followed by pump deactivation time.

[0036] In particular, the control algorithm retrieves parameters calculated from stored dispensing data for the dispensing step of the dispensing cycle immediately preceding the current dispensing cycle.

[0037] Advantageously, according to the method, it is possible to partition the brewing pump during the current dispensing step without resorting to a preliminary operation of acquiring brewing parameters.

[0038] The division of the brew pumps is based on a history of stored dispensing data of cycles previously performed by the coffee machine, but not only.

[0039] Preferably, in fact, the algorithm also acquires a piece of data representative of the amount of coffee powder used to perform the current dispensing cycle.

[0040] Even more preferably, if a wetting step is provided for performing the current dispensing cycle, the control algorithm also acquires a data sheet representative of the type of wetting step used for performing the current dispensing cycle.

[0041] In this way, the controller controls the dispensing speed of the entire dispensing step of the current dispensing cycle not only based on the dispensing data of the previous dispensing cycle, but also in a preferred manner based on the current amount of coffee powder used and, if a wetting step is provided for the current dispensing cycle, based on the type of wetting step used for the current dispensing cycle.

[0042] According to a preferred embodiment, if a plurality of types of wetting steps are provided available, the stored dispensing data are differentiated based on the type of wetting step used.

[0043] This differentiation of the stored data allows for greater pump partitioning accuracy.

[0044] According to a preferred embodiment, the electronic controller calculates said parameters obtained by an algorithm for pump partitioning.

[0045] Preferably, if a plurality of available wetting step types are provided, the controller calculates a distinguishing parameter for each available wetting step type, and stores each calculated parameter for subsequent selective retrieval by the algorithm.

[0046] In this case, the electronic controller controls the dispensing speed by dividing the brewing pump using a control algorithm that has acquired the amount of coffee powder, the type of wetting step and the parameters corresponding to this type of wetting step.

[0047] In a preferred embodiment of the invention, the control algorithm for dividing the brewing pump calculates parameters of a periodic control function, comprising at least one value of the activation time in the period and optionally also the value of the period of this control function, which value may be chosen alternatively.

[0048] Specifically, the period of this control function includes a unique continuous activation time and a unique continuous deactivation time.

[0049] In more detail, the continuous activation time corresponds to activation at the rated power of the brewing pump.

[0050] Therefore, if Figure 2 As shown, the division of the brewing pump is preferably realized by a square wave function.

[0051] The stored allocation data may be a plurality of data, and the greater the number of data of each previous allocation cycle, the greater the degree of optimization of the allocation speed of the current allocation cycle.

[0052] In particular, such stored allocation data is obtained during a plurality of current allocation cycles.

[0053] However, it should be noted that it is not necessary to store the allocation data of all previous allocation cycles.

[0054] In practice, data from multiple previous allocations may be sufficient to obtain an effective optimization of the allocation speed, since the calculated parameters are the result of statistical calculations.

[0055] In particular, the parameters are recalculated at each new dispensing cycle by a mathematical function comprising a simple average and / or a weighted average and / or an accumulator and / or a moving average.

[0056] Preferably, the stored dispensing data comprises the duration of the dispensing step of said previous dispensing cycle.

[0057] More preferably, the stored dispensing data comprises the amount of product dispensed in said previous dispensing cycle.

[0058] Even more preferably, said stored dispensing data comprises the amount of coffee powder used in said previous dispensing cycle.

[0059] And still preferably, said stored dispensing data comprises said parameters of said control function calculated in said previous dispensing cycle.

[0060] The invention also comprises a coffee machine comprising an electronic controller provided with a non-volatile memory unit, a brewing pump and a brewing unit having a receiving chamber with a quantity of coffee grounds.

[0061] The non-volatile memory is configured to store a control algorithm and dispensing data for a dispensing step of a dispensing cycle preceding a current dispensing cycle.

[0062] The electronic controller is configured to control the brewing pump to maintain a dispensing speed throughout the dispensing step of the current dispensing cycle within a set point value or a predetermined range thereof by dividing the brewing pump by a control algorithm, the control algorithm obtaining parameters calculated from the stored dispensing data of the dispensing step of the dispensing cycle just before the current dispensing cycle.

[0063] Embodiment 1

[0064] The following stored allocation data exists in non-volatile memory:

[0065]

[0066] Prior to dispensing cycle n, the controller calculates the parameter par(n) for partitioning the pump.

[0067] Par(n)=f(t n-1 ,t n-2 ,t n-3 ,v n-1 ,v n-2 ,v n-3 ,g n-1 ,g n-2 ,g n-3 ,ton n-1 ,ton n-2 ,ton n-3 ,T n-1 ,T n-2 ,T n-3 ).

[0068] The algorithm acquires a data slice of the amount of coffee powder g(n) used for the current dispensing cycle.

[0069] The algorithm calculates the pump partition parameters and generates ton n =k t (g(n);Par(n)) and T n =k T (g(n);Par(n))

[0070] In order to obtain a value of the dispensing speed of the current dispensing cycle, such as being as close as possible to the defined set point value, the controller commands the brewing pump with said division parameters generated by the algorithm.

[0071] Example II

[0072] Figure 2 It is shown that a plurality of types of wetting steps a, b and c can be performed (type = a, b, c).

[0073] Prior to dispensing cycle n, the controller calculates parameters for partitioning the pump for each wetting type.

[0074] Par a (n) = f(t n-1 ,t n-2 ,t n-3 ,v n-1 ,v n-2 ,v n-3 ,g n-1 ,g n-2 ,gn-3 ,ton n-1 ,ton n-2 ,ton n-3 ,T n-1 ,T n-2 ,T n-3 )

[0075] Par b (n) = f(t n-1 ,t n-2 ,t n-3 ,v n-1 ,v n-2 ,v n-3 ,g n-1 ,g n-2 ,g n-3 ,ton n-1 ,ton n-2 ,ton n-3 ,T n-1 ,T n-2 ,T n-3 )

[0076] Par c (n) = f(t n-1 ,t n-2 ,t n-3 ,v n-1 ,v n-2 ,v n-3 ,g n-1 ,g n-2 ,g n-3 ,ton n-1 ,ton n-2 ,ton n-3 ,T n-1 ,T n-2 ,T n-3 )

[0077] In this case, the algorithm:

[0078] - obtaining a data slice of the amount of coffee powder g(n) for the current dispensing cycle;

[0079] - obtaining a data slice representing the type type(n) of the preliminary wetting step for the current dispensing cycle, e.g. type(n)=b; and

[0080] - Calculate the pump partition, generating:

[0081] ton n =k tb (g(n);Par b (n)) and T n =k Tb (g(n);Par b(n))

[0082] The controller commands the brew pump with the partitioning parameters generated by the algorithm.

[0083] Embodiments using control algorithms

[0084] The pump split algorithm aims to maintain the set point value of the dispense rate (expressed in cc / second) constant within a given optimal range.

[0085] The algorithm uses the following parameters previously obtained in the previous "n-1" allocation cycles:

[0086] - Pump start time ton i

[0087] - Pump drive period T i

[0088] - Duration of beverage brewing t i

[0089] -The amount of beverage dispensed during brewing v i

[0090] -Amount of coffee powder in the drink g i

[0091] - Type of wetting of coffee powder (A, B, C, D, etc.)

[0092] Where i=1....n-1

[0093] And uses the following parameters related to the current allocation cycle:

[0094] - Type of wetting of the coffee powder of the beverage being prepared (A, B, C, D, etc.)

[0095] - Amount of coffee powder in the drink being made, g n

[0096] The starting data for the algorithm for the first dispense is based on factory pre-installed data.

[0097] Based on these data and subsequently saved during the allocation, the algorithm selects ton n and T n or if T is selected n Then select only ton n .

[0098] Assume that T is selected n , then for the beverage being executed, ton n Will have the following proportions:

[0099] - is proportional to the coffee powder of the beverage "n" being performed. The greater the amount of powder in the beverage to be dispensed, the ton n Refer to the allocation #4 in the table below.

[0100] #23 and #16 as examples.

[0101] - with the period T selected for the beverage "n" being executed n Proportional to the period T n The longer, the ton n The larger the value, the smaller the size. See assignments #26, #28 or #23, #24 in the table below as examples.

[0102] - inversely proportional to the average dispensing speed of the previous "n-1" beverages (weighted according to their divisions) for the same type of wetting (A, B, C or D) and the same amount of powder (wherein the dispensing speed of a beverage is the ratio between the amounts of beverage dispensed in the brewing time [cc / s]). If the average dispensing speed of the previous beverage is greater than the desired dispensing speed setpoint value, then the average ton / T of the previous beverage is inversely proportional to the average dispensing speed of the previous beverages (weighted according to their divisions). n ratio compared to the ton of beverage being administered n / T n The ratio will decrease; if the average dispense rate of the previous beverage is lower than the set point value, the ton of the previous beverage i Compared to the ton of drinks being performed n For example, see allocations #5, #6, and #7 in the table below as examples where, for simplicity, the algorithm is assumed to work only in the previous allocation cycle.

[0103] Example Data for the Pump Partitioning Algorithm

[0104]

[0105]

[0106] For the nth distribution falling within a certain type of powder wetting / pre-brew, ton is summarized in the general formula n , with the directly proportional term (bond) as the numerator and the inversely proportional term as the denominator:

[0107]

[0108] The control method as conceived herein is susceptible to numerous modifications and variations, all of which fall within the scope of the inventive concept; moreover, all details may be replaced with technically equivalent elements. In practice, the materials used, as well as the dimensions, may be determined according to requirements and the state of the art.

Claims

1. A control method for controlling a current dispensing cycle of a coffee machine comprising an electronic controller, a brewing pump and a brewing unit having a receiving chamber for a quantity of coffee powder, wherein the current dispensing cycle comprises a dispensing step and a possible preliminary step of wetting the quantity of coffee powder, in which preliminary step no dispensing has yet taken place, wherein The electronic controller uses a control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) divides the brewing pump to control the dispensing speed of the entire dispensing step of the current dispensing cycle, and the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) obtains a parameter (Par(n)) calculated from stored dispensing data of a dispensing step of a dispensing cycle immediately preceding the current dispensing cycle, wherein the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) obtains a data piece representing the amount of coffee powder (g(n)) used to perform the current dispensing cycle, wherein the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) calculates the parameters of the periodic control function, including the period of the function (T n =k T (g(n);Par(n))) and the period (T n ) in the startup time (ton n =k t (g(n); Par(n))) values, wherein the stored dispensing data comprises the duration (t n-1 , t n-2 , t n-3 ...), the amount of product dispensed in the previous dispensing cycle (v n-1 , v n-2 , v n-3 ...), the amount of coffee powder used in the previous dispensing cycle (g n-1 , g n-2 , g n-3 ...) and the parameters (ton n-1 ,ton n-2 ,ton n-3 , …, T n-1 , T n-2 , T n-3 …).

2. A control method for controlling a current dispensing cycle of a coffee machine according to claim 1, wherein the control method is characterized in that, if a wetting step for performing the current dispensing cycle is provided, the control algorithm acquires a data sheet representing the type of wetting step for performing the current dispensing cycle.

3. A control method for controlling a current dispensing cycle of a coffee machine according to claim 1 or 2, characterized in that the period comprises a unique continuous activation time and a unique continuous deactivation time.

4. The control method for controlling a current dispensing cycle of a coffee machine according to claim 3, wherein the activation of the brewing pump at rated power corresponds to the continuous activation time.

5. A control method for controlling a current dispensing cycle of a coffee machine according to claim 2, characterized in that, once the type (A, B, C, D) of the preliminary wetting step and the amount of coffee powder of the current dispensing cycle are determined, the brewing pump activation time in the current dispensing cycle is proportional to the amount of coffee powder of the beverage in the current dispensing cycle and inversely proportional to the average dispensing speed of previous dispensing cycles weighted based on their division, the previous dispensing cycles being for the same type (A, B, C or D) of wetting and the same amount of powder as the current dispensing cycle.

6. An automatic coffee machine, comprising an electronic controller provided with a non-volatile memory unit, a brewing pump, a brewing unit having a receiving chamber for a certain amount of coffee powder, wherein the non-volatile memory is configured to store a control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) and the dispensing data of the dispensing step of the dispensing cycle before the current dispensing cycle, the electronic controller is configured to control the dispensing data by the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) divides the brewing pump to calculate the dispensing speed of the entire dispensing step of the current dispensing cycle, and the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) obtains a parameter (Par(n)) calculated from said stored dispensing data of a dispensing step of a dispensing cycle just before said current dispensing cycle, wherein said control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) obtains a data piece representing the amount of coffee powder (g(n)) used to perform the current dispensing cycle, wherein the control algorithm (k t (g(n);Par(n)) and k T (g(n); Par(n))) calculates the parameters of the periodic control function, including the period of the function (T n =k T (g(n);Par(n))) and the period (T n ) in the startup time (ton n =k t (g(n); Par(n))) values, wherein the stored dispensing data comprises the duration (t n-1 , t n-2 , t n-3 ...), the amount of product dispensed in the previous dispensing cycle (v n-1 , v n-2 , v n-3 ...), the amount of coffee powder used in the previous dispensing cycle (g n-1 , g n-2 , g n-3 ...) and the parameters (ton n-1 ,ton n-2 ,ton n-3 , …, T n-1 ,T n-2 ,T n-3 …)。

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