Coffee machine and flow rate control method thereof

Abstract

The present invention belongs to the technical field of coffee machines, and specifically provides a coffee machine and a flow rate control method thereof. The coffee machine of the present invention includes a compression device for compressing coffee powder and a water pump for driving water to brew coffee powder. The flow rate control method of the present invention includes: determining the target flow rate Ld of the coffee liquid generated when the coffee machine extracts coffee powder according to the set parameters; determining the current flow rate La of the coffee liquid generated when the coffee machine extracts coffee powder with the current parameters; judging whether the current flow rate La is equal to the target flow rate Ld; if they are not equal, adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder so that the current flow rate La is equal to the target flow rate Ld. The present invention can determine the target flow rate Ld according to different set parameters, and by adjusting the water supply flow rate Lsb of the water pump and / or the pressing force on the coffee powder, effectively make the current flow rate La equal to the target flow rate Ld, thereby achieving accurate extraction of different types of coffee and improving the taste of coffee.

Description

Technical Field

[0001] The invention belongs to the technical field of coffee machines, and specifically provides a coffee machine and a flow rate control method thereof. Background Art

[0002] A coffee machine is a machine that brews and extracts coffee powder into a coffee solution. Since coffee powder is loose, hot water will more easily flow through the less dense channels and bypass the denser parts when passing through the coffee powder. This uneven water flow will lead to uneven extraction, with some coffee powder being over-extracted and tasting bitter, and some coffee powder being under-extracted and tasting light, affecting the taste of the final coffee solution.

[0003] For this reason, some coffee machines are also equipped with a compression device to compress the coffee powder into a cake shape, making the density of the coffee powder more uniform. Furthermore, during the extraction process, especially during high-pressure extraction, the uniform-density cake structure can prevent the coffee powder from shifting or being dispersed under the impact of the high-pressure water flow. In addition, the compacted coffee powder can ensure that the brewing water pressure of the water flow is evenly distributed throughout the cake-shaped coffee powder.

[0004] On this basis, the coffee liquid produced when the coffee machine extracts coffee powder, that is, the solution formed after water passes through the coffee powder, the flow rate (formation speed) will affect the contact time between water and coffee powder, thus affecting the concentration of coffee oils, flavor substances, etc. in the coffee liquid, and further affecting the taste of the coffee. At the same time, the density of the coffee powder after being compressed will also affect the flow rate of the coffee liquid.

[0005] However, the prior art generally brews coffee powder with a substantially constant water flow based on past experience, which easily leads to the flow rate (formation speed) of the coffee liquid being too large or too small, thus affecting the taste of the final coffee solution. Summary of the invention

[0006] One object of the present invention is to solve the problem that the flow rate of the coffee liquid in the existing coffee machine is too high or too low, which affects the taste of the final coffee solution.

[0007] To achieve the above object, the present invention provides a flow rate control method of a coffee machine in a first aspect, wherein the coffee machine comprises a compression device for compressing coffee powder and a water pump for driving water to brew the coffee powder; the flow rate control method comprises:

[0008] Determining a target flow rate Ld of coffee liquid generated when the coffee machine extracts the coffee powder according to the set parameters;

[0009] Determine a current flow rate La of coffee liquid generated when the coffee machine extracts the coffee powder with current parameters;

[0010] Determine whether the current flow rate La is equal to the target flow rate Ld;

[0011] If they are not equal, adjust the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder to make the current flow rate La equal to the target flow rate Ld.

[0012] Optionally, the setting parameters include at least one of the roasting degree of the coffee, the grinding level of the coffee, the type of coffee beans and the type of coffee brewing.

[0013] Optionally, determining a current flow rate La of coffee liquid generated when the coffee machine extracts the coffee powder with current parameters comprises:

[0014] La=(1-x)·f·Lsb Formula (1)

[0015] Wherein, x is the water permeability coefficient of the compressed coffee powder, and f is the water permeability correlation coefficient of the brewer of the coffee machine.

[0016] Optionally, the adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder includes:

[0017] The target water supply flow rate Lsbt of the water pump is determined by the following formula (2):

[0018]

[0019] The working parameters of the water pump are adjusted so that Lsb=Lsbt.

[0020] Optionally, when the water supply flow rate Lsb reaches the maximum water supply flow rate Lsbmax of the water pump, if La is still not equal to Ld, adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder further includes:

[0021] The target pressing force Ft is determined by the following formula (3):

[0022]

[0023] Adjusting the working parameters of the compression device so that the compression force of the compression device on the coffee powder is F=Ft;

[0024] Wherein, W is the setting parameter or is determined according to the setting parameter, and Fmax is the maximum compression force that the compression pack can provide to the coffee powder.

[0025] Optionally, Lsbmax, Fmax, Lsb before adjustment and F before adjustment are all pre-stored in the coffee machine.

[0026] In a second aspect, the present invention provides a coffee machine, comprising:

[0027] A brewing device for containing coffee powder;

[0028] A compression device, used for compressing the coffee powder;

[0029] A water pump, used for supplying water to the brewer;

[0030] A flow rate sensor, used to detect the water supply flow rate Lsb of the water pump;

[0031] A controller is configured to control the coffee machine to execute the flow rate control method described in any one of the first aspects.

[0032] Optionally, the controller determines the compression force F of the compression device on the coffee powder through the working parameters of the compression device; and / or, the coffee machine also includes a water tank, which is connected in series upstream of the water pump.

[0033] Optionally, the coffee machine further comprises a boiler and a temperature sensor, wherein the boiler is connected in series downstream of the water pump and is used to heat the water therein; and the temperature sensor is used to detect the temperature of the water flowing out of the boiler.

[0034] Optionally, the coffee machine further comprises a waste water container and a reversing valve, wherein the waste water container is used to receive cold water; and the reversing valve is used to control the water flowing out of the boiler to flow to the waste water container or to the brewer.

[0035] Based on the foregoing description, it can be understood by those skilled in the art that in the aforementioned technical solution of the present invention, the target flow rate Ld of the coffee liquid generated when the coffee machine extracts the coffee powder is determined according to the set parameters, so that the target flow rate Ld of the coffee liquid can be adapted to the user's setting of the coffee machine parameters. By judging whether the current flow rate La is equal to the target flow rate Ld; and when they are not equal, adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder so that the current flow rate La is equal to the target flow rate Ld, the coffee machine of the present invention can make the current flow rate La consistent with the target flow rate Ld, thereby ensuring the taste of the final coffee solution. In short, the present invention enables the coffee machine to automatically determine the target flow rate Ld according to the parameters set by the user, and then automatically adjust the working parameters of the water pump and the compression device according to the target flow rate, so that the actual current flow rate La of the coffee machine is consistent with the target flow rate Ld, thereby ensuring the taste of the final coffee solution.

[0036] Furthermore, the present invention determines the current flow rate La by La=(1-x)·f·Lsb, so that the current flow rate La takes into account the water supply flow rate Lsb of the water pump, the characteristics of the compressed coffee powder, and the characteristics of the brewer. The value is more accurate and the coffee extraction effect is better. However, those skilled in the art usually only consider the water supply flow rate Lsb of the water pump and keep the water supply flow rate Lsb of the water pump constant; they do not consider the characteristics of the compressed coffee powder and the characteristics of the brewer, so the present invention also overcomes this technical bias of those skilled in the art. Moreover, it is precisely because the present invention overcomes this technical bias that the water supply flow rate Lsb of the water pump of the present invention can be adapted to the degree of compression of the coffee powder (water permeability coefficient x) and the water permeability correlation coefficient f of the brewer, thereby enabling the coffee powder to be properly extracted and have a better taste.

[0037] Other beneficial effects of the present invention will be described in detail below in conjunction with the accompanying drawings so that those skilled in the art can more clearly understand the improved purposes, features and advantages of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solution of the present invention, some embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood by those skilled in the art that the same reference numerals indicate the same or similar components or parts in different drawings; the drawings of the present invention are not necessarily drawn to scale.

[0039] In the attached figure:

[0040] Figure 1 It is a schematic diagram of the principle of the coffee machine provided by the present invention;

[0041] Figure 2 is a flow chart of the steps of a flow rate control method of a coffee machine in some embodiments of the present invention.

[0042] Description of reference numerals:

[0043] 100, coffee machine; 200, coffee powder; 300, coffee liquid;

[0044] 101. Water tank; 102. Water pump; 103. Boiler; 104. Reversing valve; 105. Brewing device; 106. Coffee nozzle; 107. Compression device; 108. Waste water container; 109. Flow rate sensor; 110. Temperature sensor; 111. Pressure sensor; 112. Controller. DETAILED DESCRIPTION

[0045] It should be understood by those skilled in the art that the embodiments described below are only some embodiments of the present invention, rather than all embodiments of the present invention, and these embodiments are intended to explain the technical principles of the present invention, rather than to limit the protection scope of the present invention. Based on the embodiments provided by the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should still fall within the protection scope of the present invention.

[0046] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "top", "bottom", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the corresponding devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0047] Furthermore, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internal communication between two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. For example, the terms "install", "connect", "connect" and "fix", unless otherwise specifically described, can specifically be any feasible connection such as bolt connection, screw connection, welding, plug-in connection, riveting, melting, clamping, etc. Figure 1 As shown, in an example provided by the present invention, the coffee machine 100 includes a water tank 101, a water pump 102, a boiler 103, a reversing valve 104, a brewer 105, a coffee nozzle 106, a compression device 107, a waste water container 108, a flow rate sensor 109, a temperature sensor 110, a pressure sensor 111 and a controller 112.

[0048] The water tank 101, the water pump 102, the boiler 103, the reversing valve 104 and the brewer 105 are fluidically connected in sequence, the coffee nozzle 106 is arranged at the bottom side of the brewer 105, the compression device 107 is used to compress the coffee powder 200 in the brewer 105, the waste water container 108 is fluidically connected to the reversing valve 104, the flow rate sensor 109 is used to detect the water supply flow rate Lsb of the water pump 102, the temperature sensor 110 is used to detect the temperature of the water in or flowing out of the boiler 103, and the pressure sensor 111 is used to detect the water pressure. The boiler 103, the reversing valve 104, the compression device 107, the flow rate sensor 109, the temperature sensor 110 and the pressure sensor 111 are electrically connected to the controller 112 respectively.

[0049] exist Figure 1 In the example shown, the water tank 101 is used to store water, and has a water filling port (not shown in the figure) on the top thereof, so that a user can fill water into the water tank 101 through the water filling port.

[0050] exist Figure 1 In the example shown, the flow rate sensor 109 may be disposed between the water pump 102 and the water tank 101 , or may be disposed downstream of the water pump 102 away from the water tank 101 .

[0051] Those skilled in the art will appreciate that when the water flow rate detected by the flow rate sensor 109 suddenly decreases during the operation of the water pump 102, it indicates that the water in the water tank 101 is lacking or has been used up. At this time, the coffee machine 100 allows the user to add water to the water tank 101.

[0052] In the present invention, the flow velocity sensor 109 may be a sensor of any form, such as a blade type, a vortex type, or a Karman vortex type.

[0053] exist Figure 1 In the example shown, the boiler 103 is connected in series downstream of the water pump 102 and is used to heat the water therein. The boiler 103 may specifically include a container and an electric heating wire arranged inside and / or outside the container to heat the water in the container through the electric heating.

[0054] exist Figure 1 In the example shown, the temperature sensor 110 is used to detect the temperature of water flowing out of the boiler 103. The temperature sensor 110 can be a resistance sensor or a thermocouple sensor.

[0055] exist Figure 1 In the example shown, the waste water container 108 is used to receive cold water, and the reversing valve 104 is used to control the water flowing out of the boiler 103 to flow to the waste water container 108 or to the brewer 105 .

[0056] exist Figure 1In the example shown, the brewer 105 is used to contain coffee powder 200. The brewer 105 can be a container as a whole, such as a cup with an open top. A plurality of filter holes (not shown in the figure) are provided on the bottom wall of the brewer 105 so that water for brewing coffee powder 200 flows out from the filter holes.

[0057] exist Figure 1 In the example shown, when the temperature sensor 110 detects that the water temperature has not reached a preset temperature (e.g., 50°C, 75°C, 80°C, 85°C, 95°C, 98°C, etc.), the reversing valve 104 controls the water flowing out of the boiler 103 to flow to the waste water container 108; when the temperature sensor 110 detects that the water temperature has reached a preset temperature, the reversing valve 104 controls the water flowing out of the boiler 103 to flow to the brewer 105, so as to brew the coffee in the brewer 105 at a constant temperature to ensure the taste of the coffee.

[0058] Furthermore, in the water flow path, the reversing valve 104 can be placed as close to the brewer 105 as possible to shorten the path of the hot water from the reversing valve 104 to the brewer 105, thereby preventing the hot water from being cooled due to the long path and affecting the brewing taste of the coffee.

[0059] Accordingly, the temperature sensor 110 is disposed between the reversing valve 104 and the boiler 103 and as close to the reversing valve 104 as possible to shorten the path of hot water from the temperature sensor 110 to the brewer 105 and prevent waste of hot water.

[0060] exist Figure 1 In the example shown, the pressure sensor 111 is used to detect the water supply flow rate Lsb of the water provided by the water pump 102. The pressure sensor 111 can be any feasible sensor such as a piezoresistive sensor, a ceramic sensor, a piezoelectric sensor, etc.

[0061] exist Figure 1 In the example shown, the coffee nozzle 106 is used to receive and discharge the coffee solution flowing out of the brewer 105. The coffee nozzle 106 can facilitate the user to receive the coffee solution and prevent the coffee solution from spilling.

[0062] exist Figure 1 In the example shown, the compression device 107 can be any feasible compression device 107, for example, including an electric push rod and a push plate driven by the electric push rod, so that the coffee powder 200 can be squeezed by the push plate when the electric push rod is extended or retracted.

[0063] In the present invention, the controller 112 is an integrated circuit chip that has the ability to process signals. The controller 112 can be a general-purpose processor, such as a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, microprocessors, and any other conventional processors. In addition, the controller 112 can also have a storage function to store computer programs and data that it can execute.

[0064] Furthermore, in the present invention, the controller 112 may be an integrated functional module or a split functional module. When the controller 112 is a split functional module, it may include a functional module with information processing capability and a functional module with storage capability.

[0065] exist Figure 1 In the example shown, the compression device 107, the water pump 102, the temperature sensor 110, the pressure sensor 111, the flow rate sensor 109, and the reversing valve 104 are electrically connected to the controller 112 respectively, so that the controller 112 obtains signals from the temperature sensor 110, the pressure sensor 111 and the flow rate sensor 109, and controls the action or operation of the compression device 107, the water pump 102 and the reversing valve 104.

[0066] The following will refer to Figure 1 The coffee machine 100 shown in the figure is used to describe the flow rate control method of the coffee machine 100 of the present invention in detail.

[0067] It should be noted that Figure 1 This is only an example of the coffee machine 100 to be protected by the present invention. Based on the context of the present invention, those skilled in the art may also modify the coffee machine 100 as needed. Figure 1 Some components of the coffee machine 100 shown in the figure are reduced, replaced, or some components are added, such as adding a liquid level gauge for measuring the water level of the water tank 101, or omitting the arrangement of the pressure sensor 111.

[0068] like Figure 2 As shown, in some embodiments of the present invention, the flow rate control method of the coffee machine 100 includes:

[0069] Step S100, determining a target flow rate Ld of the coffee liquid 300 generated when the coffee machine 100 extracts the coffee powder 200 according to the set parameters;

[0070] Step S200, determining a current flow rate La of the coffee liquid 300 generated when the coffee machine 100 extracts the coffee powder 200 with current parameters;

[0071] Step S300, determining whether the current flow rate La is equal to the target flow rate Ld;

[0072] Step S400, if they are not equal, adjust the water supply flow rate Lsb of the water pump 102 and / or the pressing force F of the compression device 107 on the coffee powder 200 to make the current flow rate La equal to the target flow rate Ld.

[0073] It can be understood by those skilled in the art that the present invention determines the target flow rate Ld of the coffee liquid 300 generated when the coffee machine 100 extracts the coffee powder 200 according to the set parameters, so that the target flow rate Ld of the coffee liquid 300 can be adapted to the user's setting of the coffee machine 100 parameters. By judging whether the current flow rate La is equal to the target flow rate Ld; and when they are not equal, adjusting the water supply flow rate Lsb of the water pump 102 and / or the pressing force F of the compression device 107 on the coffee powder 200, so that the current flow rate La is equal to the target flow rate Ld, the coffee machine 100 of the present invention can make the current flow rate La consistent with the target flow rate Ld, thereby ensuring the taste of the final coffee solution. In short, the present invention enables the coffee machine 100 to automatically determine the target flow rate Ld according to the parameters set by the user, and then automatically adjust the working parameters of the water pump 102 and the compression device 107 according to the target flow rate, so that the actual current flow rate La of the coffee machine 100 is consistent with the target flow rate Ld, thereby ensuring the taste of the final coffee solution.

[0074] In step S100 of the present invention, the setting parameters include at least one of the roasting degree of coffee, the grinding gear of coffee, the type of coffee beans and the type of coffee brewing. The setting parameters can be set by the user, and can be determined by the user by operating the control panel or function keys of the coffee machine 100.

[0075] Furthermore, the set parameters correspond to the target flow rate Ld and are stored in a database, which may be stored in the controller 112, a memory connected to the controller 112, or a cloud server connected to the coffee machine 100. The database containing the correspondence may be established based on a large amount of experimental data and the experience of professional baristas, or may be determined by the formula (1) described below after setting the water permeability coefficient x of the coffee powder 200, the water permeability correlation coefficient f of the brewer 105 of the coffee machine 100, and the water supply flow rate Lsb of the water pump 102.

[0076] As an example 1, set the deep roasting, the grinding gear to medium, the coffee bean type to Arabica, and the brewing shape to espresso. The target flow rate Ld corresponding to these setting parameters is determined from the database to be 1.5 ml / s (milliliters / second).

[0077] As a second example, medium roasting, coarse grinding, Robusta coffee beans, and American coffee are set. The target flow rate Ld corresponding to these setting parameters is determined from the above database to be 1 ml / s.

[0078] As example 3, light roasting, fine grinding, mixed coffee beans (including Arabica and Robusta), and brewing into latte coffee are set. The target flow rate Ld corresponding to these setting parameters is determined from the above database to be 1.2 ml / s.

[0079] Furthermore, in some embodiments of the present invention, the value of the target flow rate Ld can be a constant value during the process of extracting coffee, or can be a value that changes with the extraction time.

[0080] It is understood by those skilled in the art that, since the cross section of the pipeline detected by the flow rate sensor 109 (the cross section perpendicular to the water flow direction) is different from the cross section of the coffee powder 200 in the brewer 105 (the cross section perpendicular to the water flow direction), the flow rate in the brewer 105 is different from the flow rate detected by the flow rate sensor 109. Therefore, in step S200 of the present invention, the current flow rate La can be determined by the following formula (1):

[0081] La=(1-x)·f·Lsb Formula (1)

[0082] In formula (1), x is the water permeability coefficient of the compressed coffee powder 200, and its value range is (0,1). When x=0, it means that the compressed coffee powder 200 is completely impermeable to water; when x=1, it means that the compressed coffee powder 200 is completely permeable to water (equivalent to the fact that the coffee powder 200 does not exist). Therefore, x can be any feasible value such as 0.2, 0.4, 0.5, 0.7, 0.85, etc.

[0083] In the present invention, x can be determined by detecting the magnitude of the water flow before and after the coffee powder 200, or by the following formula:

[0084] x=K·M·N·Fmax÷F.

[0085] Among them, K is the grinding gear of the coffee beans. The finer the coffee beans are ground, the smaller the value of K is, and vice versa. For example, when the grinding gear is fine grinding, K is 0.5; when the grinding gear is medium grinding, K is 1; when the grinding gear is coarse grinding, K is 1.5.

[0086] Wherein, M is the coffee bean type correlation parameter. For example, when the coffee bean type is Robusta, M is 1; when the coffee bean type is Arabica, M is 0.9.

[0087] Where N is a parameter related to the roasting degree of coffee beans. For example, when roasted lightly, N is 0.7; when roasted medium, N is 0.8; and when roasted deeply, N is 0.9.

[0088] Among them, Fmax is the maximum compression force that the compression device 107 can provide to the coffee powder 200, which can be determined by arranging a pressure sensor 111 in the brewer 105 and making the compression device 107 compress the coffee powder 200 at the maximum output power. Alternatively, the corresponding relationship between the input current, voltage and other parameters of the compression device 107 and the compression force F on the coffee powder 200 is determined by experiments, and then the input current, voltage and other parameters of the compression device 107 are obtained to determine the compression force F of the compression device 107 on the coffee powder 200.

[0089] Among them, F is the current compression force provided by the compression device 107 to the coffee powder 200, which can be specifically determined by the pressure sensor 111 provided in the brewer 105.

[0090] Furthermore, the specific values ​​of K, M, and N mentioned above can also be determined by those skilled in the art through multiple experiments.

[0091] In formula (1), f is the water permeability correlation coefficient of the brewer 105 of the coffee machine 100, and its value range is (0,1). When f=0, it means that the brewer 105 is completely impermeable to water; when f=1, it means that the brewer 105 is completely permeable to water (equivalent to the absence of coffee powder 200). Therefore, f can be any feasible value such as 0.2, 0.25, 0.3, 0.5, etc.

[0092] Furthermore, the specific value of f can be determined by calculating the ratio of the total area of ​​the filter holes on the bottom wall of the brewer 105 to the total area of ​​the bottom wall of the brewer.

[0093] For example, if x is 0.5, f is 0.6, and Lsb is 4 ml / s, then according to formula (1), the current flow rate La is calculated to be 1.2 ml / s.

[0094] In step S400 of the present invention, the target water supply flow rate Lsbt of the water outlet pump 102 is first determined by the following formula (2):

[0095]

[0096] Then, the working parameters of the water pump 102 are adjusted so that Lsb=Lsbt.

[0097] The working parameters of the water pump 102 are mainly the rotation speed or duty cycle of the water pump 102 .

[0098] For example, assuming that the current water supply flow rate Lsb of the water pump 102 is 2 ml / s, the target water supply flow rate Lsbt calculated according to formula (2) is 4.5 ml / s. Then, the working parameters of the water pump 102 of the coffee machine 100 are adjusted, and during the adjustment process, the flow rate change is monitored in real time through the flow rate sensor 109. When the water supply flow rate Lsb reaches 4.5 ml / s, the adjustment of the working parameters of the water pump 102 is stopped.

[0099] When the working parameters of the water pump 102 reach the maximum, so that the water pump 102 reaches the maximum water supply flow rate Lsbmax water pump 102, if La is still not equal to Ld, the target pressing force Ft is determined by the following formula (3):

[0100]

[0101] Subsequently, the compression device 107 of the coffee machine 100 for compressing the coffee powder 200 is adjusted so that the compression force F of the compression device 107 on the coffee powder 200 is Ft.

[0102] Wherein, W is a setting parameter or is determined according to the setting parameter, for example, W=K·M·N. K, M, and N refer to the above description.

[0103] Furthermore, in some embodiments of the present invention, Lsbmax, Fmax, Lsb before adjustment and F before adjustment are all pre-stored in the coffee machine 100, so that steps S100 to S400 can be executed before the coffee machine 100 is started, specifically, before the coffee machine 100 starts the compression device 107 and the water pump 102.

[0104] After the user sets the parameters for the coffee machine 100, the coffee machine 100 can calculate the current flow rate La when operating according to the four parameters based on the pre-stored four parameters before operation.

[0105] After the user sets the parameters, the coffee machine 100 can calculate the target flow rate Ld accordingly. Then, the coffee machine 100 compares La with Ld, and when La≠Ld, the coffee machine 100 calculates the working parameters of the water pump 102 and the compression device 107 according to the method described above, and then controls the water pump 102 and the compression device 107 to operate according to the calculated working parameters.

[0106] That is, in some embodiments of the invention, the flow rate control method of the coffee machine 100 may further include a step after step S400: controlling the coffee machine 100 to operate so as to compress and brew the coffee powder 200 .

[0107] In summary, the present invention can determine the target flow rate Ld according to different set parameters, and by adjusting the water supply flow rate Lsb of the water pump 102 and / or the pressing force F on the coffee powder 200, effectively make the current flow rate La equal to the target flow rate Ld, thereby achieving accurate extraction of different types of coffee and improving the taste of coffee.

[0108] So far, the technical solution of the present invention has been described in combination with the above multiple embodiments, but it is easy for those skilled in the art to understand that the protection scope of the present invention is not limited to these specific embodiments. Without departing from the technical principles of the present invention, those skilled in the art can split and combine the technical solutions in the above embodiments, and can also make equivalent changes or replacements to the relevant technical features. Any changes, equivalent replacements, improvements, etc. made within the technical concept and / or technical principles of the present invention will fall within the protection scope of the present invention.

[0109] In the present invention, the term "communication" means fluid communication, so as to allow fluid (such as air, liquid) to flow between two connected objects. And the "communication" can be to allow the fluid to flow between the two connected objects without leakage, or to allow the fluid to flow between the two connected objects with a little leakage.

Claims

1. A method for controlling the flow rate of a coffee machine, the coffee machine comprising a compression device for compressing coffee powder and a water pump for driving water to brew the coffee powder; The flow rate control method comprises: Determining a target flow rate Ld of coffee liquid generated when the coffee machine extracts the coffee powder according to the set parameters; Determine a current flow rate La of coffee liquid generated when the coffee machine extracts the coffee powder with current parameters; Determine whether the current flow rate La is equal to the target flow rate Ld; If they are not equal, adjust the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder to make the current flow rate La equal to the target flow rate Ld.

2. The flow rate control method according to claim 1, wherein: The setting parameters include at least one of the roasting degree of coffee, the grinding level of coffee, the type of coffee beans and the type of coffee brewing.

3. The flow rate control method according to claim 1, wherein: The determining of a current flow rate La of coffee liquid generated when the coffee machine extracts the coffee powder with current parameters comprises: La=(1-x)·f·Lsb Formula (1) Wherein, x is the water permeability coefficient of the compressed coffee powder, and f is the water permeability correlation coefficient of the brewer of the coffee machine.

4. The flow rate control method according to claim 3, wherein: The adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder includes: The target water supply flow rate Lsbt of the water pump is determined by the following formula (2): The working parameters of the water pump are adjusted so that Lsb=Lsbt.

5. The flow rate control method according to claim 4, wherein: When the water supply flow rate Lsb reaches the maximum water supply flow rate Lsbmax of the water pump, if La is still not equal to Ld, adjusting the water supply flow rate Lsb of the water pump and / or the pressing force F of the compression device on the coffee powder further includes: The target pressing force Ft is determined by the following formula (3): Adjusting the working parameters of the compression device so that the compression force of the compression device on the coffee powder is F=Ft; Wherein, W is the setting parameter or is determined according to the setting parameter, and Fmax is the maximum compression force that the compression pack can provide to the coffee powder.

6. The flow rate control method according to claim 5, wherein: Lsbmax, Fmax, Lsb before adjustment, and F before adjustment are all pre-stored in the coffee machine.

7. A coffee machine, comprising: A brewing device for containing coffee powder; A compression device, used for compressing the coffee powder; A water pump, used for supplying water to the brewer; A flow rate sensor, used to detect the water supply flow rate Lsb of the water pump; A controller configured to control the coffee machine to execute the flow rate control method according to any one of claims 1 to 6.

8. The coffee machine according to claim 7, wherein: The controller determines the pressing force F of the compression device on the coffee powder according to the working parameters of the compression device; and / or, The coffee machine further comprises a water tank which is connected in series upstream of the water pump.

9. The coffee machine according to claim 7, further comprising a boiler and a temperature sensor, The boiler is connected in series downstream of the water pump and is used to heat the water therein; The temperature sensor is used to detect the temperature of water flowing out of the boiler.

10. The coffee machine according to claim 9, wherein: The coffee machine also includes a waste water container and a reversing valve. The waste water container is used to receive cold water; The reversing valve is used to control the water flowing out of the boiler to flow to the waste water container or to the brewer.

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