Automatic coffee machine and coffee extraction method

Abstract

The purpose of the present invention is to provide an automatic coffee machine and a coffee extraction method capable of increasing the concentration of coffee. The automatic coffee machine for achieving the above purpose comprises: a coffee bean storage box for storing coffee beans; a grinder module for grinding the coffee beans supplied from the coffee bean storage box; an extractor module for dispensing the coffee beans pulverized in the grinder module; a mashing module for mashing the crushed coffee beans stored in the extractor module; a coffee extraction port for discharging the liquid-phase coffee extracted from the tamping module; an extractor module rotation driving portion that rotates the extractor module between the grinder module and the ramming module so as to face the grinder module or the ramming module; and a control unit that performs control such that the dosing and the tamping are performed a plurality of times, respectively.

Description

Technical Field

[0001] This invention relates to an automatic coffee machine capable of automatically extracting coffee. Background Technology

[0002] Reference Figure 1 and Figure 2 This section describes existing automatic coffee machines.

[0003] The automatic coffee machine includes: a coffee bean storage tank 10 for storing coffee beans; a grinder module 20 for grinding the coffee beans supplied from the coffee bean storage tank 10; an extractor module 30 for dispensing the coffee beans ground in the grinder module 20; a tamping module 40 for tamping the ground coffee beans from the extractor module 30; and a coffee extraction port 50 for discharging the liquid coffee extracted from the tamping module 40.

[0004] The extractor module 30 may have a coffee bean receiving space 31 for receiving coffee beans crushed in the grinder module 20, and a coffee extraction flow path 34 for allowing the extracted liquid coffee to flow toward the coffee extraction port 50 is formed on the base 32 provided at the lower part of the coffee bean receiving space 31.

[0005] The tamping module 40 includes: a tamping module housing 41, internally equipped with a tamping module flow path 42; and a water distribution screen 43, attached to the lower end of the tamping module housing 41. The water distribution screen 43 has multiple holes to supply water supplied through the tamping module flow path 42 to the coffee beans contained in the coffee bean receiving space 31. The tamping module housing 41 and the water distribution screen 43 are moved integrally along the length of the tamping module housing 41 by a tamping motor (not shown).

[0006] The automatic coffee machine is equipped with a water tank 61, a pump 63, and a heater 64 for supplying water to the tamping module 40. When the pump 63 is driven by a control signal from a control unit (not shown), the water stored in the water tank 61 is heated in the heater 64 and then supplied to the tamping module 40. Reference numeral "62" indicates a flow sensor.

[0007] A method for coffee extraction in an automatic coffee machine configured as described above will be explained.

[0008] First, the initial position of the extractor module 30 is such that the coffee bean receiving space 31 is opposite the lower part of the grinder module 20. In this state, the coffee beans are ground by the grinder module 20, and the ground coffee beans are dispensed into the coffee bean receiving space 31 of the extractor module 30.

[0009] Then, the extractor module 30 from Figure 1 Rotate from upright position to Figure 2 The coffee bean receiving space 31 is positioned opposite the lower part of the tamping module 40, and the coffee beans that are crushed by the tamping module 40 are compressed and compacted in a tamping process.

[0010] After the tamping process is completed, the water supplied from the water tank 61 is heated in the heater 64 and then supplied to the coffee beans in the coffee bean receiving space 31 through the tamping module flow path 42 and the water distribution network 43. The liquid coffee extracted from the coffee beans is discharged through the coffee extraction port 50.

[0011] In the coffee extraction method described above, coffee extraction is performed after one batching and one tamping process, making it difficult to increase the amount of coffee beans dispensed into the coffee bean holding space 31. Therefore, there is a problem that the extracted coffee concentration cannot be increased and it is difficult to extract espresso.

[0012] Furthermore, after tamping, the bottom surface of the water distribution mesh 43 and the top surface of the tamped coffee bean layer are in close contact. Coffee extraction is carried out without the formation of head space. In this case, the water pressure is applied directly to the crushed coffee beans through the holes of the water distribution mesh 43. Therefore, it is difficult to apply uniform extraction pressure to the entire coffee bean, resulting in reduced extraction uniformity and channeling. Summary of the Invention

[0013] The present invention is proposed to solve the above-mentioned problems, and its purpose is to provide an automatic coffee machine that increases the coffee concentration and improves the extraction uniformity by increasing the amount of coffee beans, thereby improving the concentration of coffee with improved quality.

[0014] The automatic coffee machine of the present invention, for achieving the above-mentioned objectives, comprises: a coffee bean storage tank for storing coffee beans; a grinder module for grinding coffee beans supplied from the coffee bean storage tank; an extractor module for dispensing the coffee beans ground in the grinder module; a tamping module for tamping the ground coffee beans stored in the extractor module; a coffee extraction port for discharging liquid coffee extracted from the tamping module; an extractor module rotation drive unit for rotating the extractor module between the grinder module and the tamping module, so as to be opposite to the grinder module or opposite to the tamping module; and a control unit for controlling the dispensing and tamping to be performed multiple times respectively.

[0015] The coffee extraction method of the automatic coffee machine of the present invention includes the following steps: Step a) grinding coffee beans into a first volume in a grinder module and receiving the ground coffee beans in an extractor module for a first dispensing; Step b) driving the extractor module to rotate so that the extractor module is opposite to the tamping module; Step c) operating the tamping module to tamp the ground coffee beans in the extractor module for a first tamping, thereby forming a first tamping layer; Step d) driving the extractor module to rotate so that the extractor module is opposite to the grinder module; Step e) grinding the coffee beans into a second volume in the grinder module and receiving the ground coffee beans on top of the first tamping layer of the extractor module for a second dispensing; Step f) driving the extractor module to rotate so that the extractor module is opposite to the tamping module; Step g) driving the tamping module to tamp the coffee beans received in the extractor module for a second tamping, thereby forming a second tamping layer on the first tamping layer; and Step h) supplying water and extracting liquid coffee.

[0016] According to the present invention, the concentration of the extracted coffee can be increased.

[0017] Furthermore, by making the tamping intensity lower during the second tamping than during the first tamping, the flavor of the extracted coffee can be balanced, and uniform coffee extraction can be achieved.

[0018] Furthermore, by creating a top space, uniform coffee extraction can be achieved.

[0019] Furthermore, by allowing users to set the tamping intensity, various coffee flavors can be provided according to the user's taste. Attached Figure Description

[0020] Figure 1 This diagram illustrates the process of grinding and dispensing coffee beans in an existing coffee machine.

[0021] Figure 2 This diagram illustrates the process of coffee extraction after tamping in an existing coffee machine.

[0022] Figure 3 This is a diagram showing the configuration of a coffee machine according to the present invention.

[0023] Figure 4 This is a diagram showing the extractor module of the coffee machine equipped with the present invention.

[0024] Figure 5 This is a diagram showing the extractor module of the coffee machine equipped with the present invention rotated to a position opposite to the tamping module.

[0025] Figure 6This is a diagram illustrating the process of grinding and dispensing coffee beans in the coffee machine of the present invention.

[0026] Figure 7 It is shown in Figure 6 The diagram shows the state in which the extractor module is rotated to be opposite to the tamping module.

[0027] Figure 8 It is shown in Figure 7 The diagram shows the process of compaction by the compaction module under the condition of [condition].

[0028] Figure 9 It is shown in Figure 8 The diagram illustrates the process of supplying water and extracting coffee under certain conditions.

[0029] Figure 10 This is a flowchart illustrating the sequence of coffee extraction performed in the coffee machine of the present invention.

[0030] Explanation of reference numerals in the attached figures Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings.

[0032] First, let's define the meaning of the following terms: Dosing refers to the act of holding ground coffee beans for coffee extraction; Tamping refers to the act of compressing and compacting the ground coffee beans held in the coffee bean receiving space 31 before coffee extraction; Puck refers to the coffee grounds after brewing espresso; Pre-infusion is the step of wetting the coffee with water before extraction in the coffee machine; Channeling refers to the phenomenon where water flows towards the side with lower density due to the inability of the ground coffee bean particles to be evenly distributed or maintain a constant density; Total Dissolved Solids (TDS) refers to the percentage of dissolved solids in coffee; Extraction yield (EXT) refers to the degree of extraction of components within the coffee beans; Headspace refers to the space between the top surface of the dosed coffee beans and the water distribution screen; Portafilter refers to a filter used to hold ground coffee beans and is installed at the extraction port to allow hot water to pass through for coffee extraction.

[0033] Reference Figures 3 to 5An automatic coffee machine 1 according to an embodiment of the present invention includes: a coffee bean storage tank 10 for storing coffee beans; a grinder module 20 for grinding coffee beans supplied from the coffee bean storage tank 10; an extractor module 30 for dispensing the coffee beans ground in the grinder module 20; a tamping module 40 for tamping the ground coffee beans stored in the extractor module 30; a coffee extraction port 50 for discharging liquid coffee extracted from the tamping module 40; an extractor module rotation drive unit 70 for rotating the extractor module 30; and a control unit (not shown) for controlling the dispensing and tamping to be performed multiple times.

[0034] The automatic coffee machine 1 is equipped with a water tank 61, a pump 63, and a heater 64 for supplying water to the tamping module 40. When the pump 63 is driven by a control signal from the control unit, the water stored in the water tank 61 flows through the water supply flow path 65 connecting the flow sensor 62 and the flow path 42 of the tamping module, and is heated in the heater 64 before being supplied to the tamping module 40.

[0035] The automatic coffee machine 1 may be equipped with a flow sensor 62 for measuring the flow rate of water supplied through the water supply path 65 and a temperature sensor (not shown) for measuring the temperature of the water.

[0036] The extractor module 30 includes: an upper housing 35, which is a cylindrical shape with open upper and lower parts; a lower housing 36, which is arranged in a stacked structure at the lower part of the upper housing 35 and is also a cylindrical shape with open upper parts; and a base 32, which is arranged in a generally cylindrical shape through the internal space of the upper housing 35 and the internal space of the lower housing 36.

[0037] The internal space of the upper shell 35 formed on the upper part of the base 32 becomes a coffee bean storage space 31 for storing the coffee beans crushed in the grinder module 20.

[0038] A filter 33 is provided on the upper surface of the base 32, and a coffee extraction flow path 34 is formed on the base 32 to allow the extracted liquid coffee to flow.

[0039] The extractor module rotation drive unit 70 rotates the extractor module 30 between the grinder module 20 and the tamping module 40 according to the control signal from the control unit, so that the coffee bean receiving space 31 of the extractor module 30 is opposite to the lower part of the grinder module 20, or so that the coffee bean receiving space 31 of the extractor module 30 is opposite to the lower part of the tamping module 40.

[0040] The tamping module 40 includes a cylindrical tamping module housing 41 with open upper and lower parts, and a water distribution network 43 connected to the lower end of the tamping module housing 41. Inside the tamping module housing 41 is a tamping module flow path 42 that is connected to the water supply flow path 65 and supplies water to the water distribution network 43.

[0041] The water distribution network 43 has multiple holes, thereby supplying water supplied through the tamping module flow path 42 to the coffee beans contained in the coffee bean containing space 31.

[0042] The automatic coffee machine 1 is equipped with a tamping motor 80 to move the tamping module housing 41 and the water distribution screen 43 as a single unit. The tamping motor 80 is connected to the tamping module housing 41 by a gear 81. When the tamping motor 80 is driven, the tamping module housing 41 moves linearly along its length to move away from or closer to the extractor module 30.

[0043] Reference Figures 6 to 10 The coffee extraction method performed in the automatic coffee machine 1 of the present invention will be described.

[0044] If the user operates the automatic coffee machine 1, the process begins from step S1. In this case, the extractor module 30 is in an initial state in which the coffee bean receiving space 31 is set opposite the lower part of the grinder module 20.

[0045] In step S1, the grinding machine module 20 is operated. That is, as follows: Figure 6 As shown, the coffee beans in the coffee bean storage tank 10 are ground by operating the grinder module 20, thereby realizing the first dispensing of the ground coffee beans into the coffee bean storage space 31 of the extractor module 30. During the first dispensing, the volume of ground coffee beans is called the first volume.

[0046] In step S2, the extractor module 30 is rotated by a set angle. That is, as shown... Figure 7 As shown, the extractor module 30 is rotated at a set angle by driving the extractor module rotation drive unit 70, so that the coffee bean receiving space 31 of the extractor module 30 is opposite to the lower part of the tamping module 40. Since the tamping module 40 is inclined at the same angle as the set angle of rotation of the extractor module 30, if the extractor module 30 rotates at the set angle, the central axis of the extractor module 30 in the longitudinal direction is aligned with the central axis of the tamping module 40 in the longitudinal direction. If the extractor module rotation drive unit 70 stops, step S3 is performed.

[0047] In step S3, the tamping motor 80 is operated in the compression direction. If the tamping motor 80 is driven in the compression direction, the driving force of the tamping motor 80 is transmitted to the tamping module housing 41 through the gear 81, such as... Figure 8 As shown, the tamping module housing 41 and the water distribution mesh 43 are integrally moved downwards and tilted toward the extractor module 30, thereby achieving the first tamping process of compressing and compacting the upper surface of the crushed coffee beans by the bottom surface of the water distribution mesh 43. This tamping process forms the first tamping layer B1.

[0048] When the tamping layer is formed by the tamping motor 80, tamping is performed at a preset tamping intensity. As an example, the tamping intensity can be set to four stages: "strongest," "strong," "medium," and "weak." During the first tamping, the tamping intensity can be set to "strongest," allowing the strongest tamping intensity to be maintained throughout multiple tamping sessions. The first tamping intensity can be preset to "strongest," or the user can select from four tamping intensity stages.

[0049] The tamping intensity can be determined by measuring revolutions per minute (RPM) in the tamping motor 80. As the tamping motor 80 compresses the coffee beans, the reaction force gradually increases, causing the RPM of the tamping motor 80 to decrease. If the RPM measured by the tamping motor 80 reaches the set RPM, it is determined that tamping has been completed at the set tamping intensity, and the tamping motor 80 is stopped. RPM1 can be set for the "strongest" tamping intensity, RPM2 for the "strong" tamping intensity, RPM3 for the "medium" tamping intensity, and RPM4 for the "weak" tamping intensity, with RPM1 being the lowest and RPM4 the highest. Alternatively, the tamping intensity can be determined by measuring the pressure applied to the tamping layer using a sensor such as a pressure sensor (not shown) or a weight sensor (not shown), instead of using RPM.

[0050] If the tamping motor 80 stops, proceed to step S4.

[0051] In step S4, a decision is made regarding whether to set a second tamping intensity. The second tamping intensity is directly set by the user and can be one of three levels: "strong," "medium," or "low," which is weaker than the first tamping intensity. The flavor of the extracted coffee can vary depending on the tamping intensity. A strong tamping intensity results in a balanced flavor (acidity + sweetness + bitterness), while a weaker tamping intensity leads to a stronger acidity. Therefore, by allowing the user to directly set the second tamping intensity, various coffee flavors can be provided.

[0052] If the judgment result indicates that a second compaction strength has been set, proceed to step S5; otherwise, proceed to step S10.

[0053] In step S5, the tamping motor 80 is operated in the return direction. If the tamping motor 80 operates in the return direction, it rotates in the opposite direction to the compression direction, thereby moving the tamping module housing 41 and the water distribution mesh 43 upward in an inclined direction, and separating the bottom surface of the water distribution mesh 43 from the upper surface of the first tamping layer B1. If the return direction operation of the tamping motor 80 stops, proceed to step S6.

[0054] In step S6, the extractor module 30 is rotated to its initial position. The extractor module rotation drive unit 70 is driven in the opposite direction to that in step S2, and rotates in the opposite direction at the same angle as the set angle in step S2. Therefore, the extractor module 30 is in an upright state, and the coffee bean receiving space 31 is positioned opposite the lower part of the grinder module 20. If the extractor module rotation drive unit 70 stops, step S7 is performed.

[0055] In step S7, the grinder module 20 is operated. The grinder module 20 grinds the coffee beans in the coffee bean storage box 10, and performs a second compaction to house the ground coffee beans in the coffee bean receiving space 31 above the first compaction layer B1. If the operation of the grinder module 20 is stopped, step S8 is performed. The volume of coffee beans ground in step S7 is called the second volume. The second volume can be configured to be smaller than the first volume, and can be set to various volumes. The second volume can be set within the range that when the extractor module 30 rotates in step S8 after the second compaction, the ground coffee beans will not be interfered with by surrounding structures and will not overflow outside the extractor module 30.

[0056] In step S8, the extractor module 30 is rotated at a set angle. Step S8 is the same process performed in step S2. If the extractor module rotation drive unit 70 stops, then step S9 is performed.

[0057] In step S9, the tamping motor 80 is operated in the compression direction to achieve the second tamping process. The intensity of the second tamping can be set to select from "strong," "medium," and "weak." If the RPM of the tamping motor 80 corresponding to the selected tamping intensity is reached, the tamping motor 80 is stopped, and the process proceeds to step S10. Through the second tamping, a second tamping layer B2 is formed on top of the first tamping layer B1.

[0058] The second tamping layer B2 is tamped with a weaker intensity than the first tamping layer B1. Therefore, when extracting coffee, the taste of the extracted coffee is different from that extracted from the first tamping layer B1.

[0059] In step S10, the operation of the tamping motor 80 is stopped. If the RPM measured by the tamping motor 80 is RPM2 when the second tamping intensity is "strong," then the tamping motor 80 stops. If the RPM is RPM3 when the second tamping intensity is "medium," then the tamping motor 80 stops. If the RPM is RPM4 when the second tamping intensity is "weak," then the tamping motor 80 stops. If the tamping motor 80 stops, the pre-infusion process of steps S11 and S12 is performed.

[0060] In step S11, warm water is supplied to the extractor module 30 during a first set time period. That is, as... Figure 9 As shown, water supplied from water tank 61 is heated in heater 64 and then supplied to the first tamping layer B1 and the second tamping layer B2 of coffee bean receiving space 31 through tamping module flow path 42 and water distribution network 43. As an example, the first set time can be set to 1 second. If the first set time has elapsed, the warm water supply is interrupted and the process proceeds to step S12.

[0061] In step S12, the system remains in standby mode for the second set time period, during which the coffee beans are steeped and the gas is released. As an example, the second set time can be set to 7 seconds. After the second set time has elapsed, the process proceeds to step S13.

[0062] In step S13, warm water is supplied to the extractor module 30 during a third set time period. The liquid coffee extracted from the first tamping layer B1 and the second tamping layer B2 passes through the coffee extraction flow path 34 and is discharged through the coffee extraction port 50, thereby ending the coffee extraction process.

[0063] In this configuration, the second compaction layer B2, which forms the uppermost compaction layer, has a weaker compaction strength compared to the first compaction layer B1. This results in a lower density in the second compaction layer B2, allowing water to easily penetrate and thus distributing the pressure evenly throughout it. Because this uniform extraction pressure acts on the entire second compaction layer B2, where warm water first comes into contact, extraction uniformity is improved. Furthermore, the strong first compaction layer B1 supports the lower part, preventing channeling. Additionally, the second compaction layer B2 can replace the headspace, thus achieving uniform extraction even without forming a separate headspace.

[0064] The above configuration involves forming the first compacted layer B1 and the second compacted layer B2 through two mixing and tamping processes. However, it is also possible to form three or more compacted layers by repeating the mixing and tamping process three or more times according to the method described above. In the case of mixing and tamping three or more times, the tamping intensity after the second tamping in the multiple tamping processes can be set to gradually weaken as tamping progresses.

[0065] Furthermore, the coffee extraction method described above involves a method that does not form a head space, but it can also be constructed using a method that forms a head space. A head space forming step can be added between step S10 and step S11 or between step S12 and step S13.

[0066] In the headspace formation step, the tamping motor 80 is rotated in the opposite direction to the tamping process, causing the water distribution mesh 43 to move upwards from the top of the tamping layer, thereby separating the upper surface of the tamping layer from the bottom surface of the water distribution mesh 43. Forming a headspace allows for the application of uniform pressure to the compressed, ground coffee beans, resulting in uniform extraction.

[0067] After the final tamping is completed, the bottom surface of the water distribution mesh 43 is in contact with the upper surface of the tamping layer. If a topspace forming step is added between steps S12 and S13, the coffee beans are wetted during the pre-soaking process. Therefore, even if the water distribution mesh 43 is separated from the coffee beans to form a topspace, the coffee beans will not stick to the bottom surface of the water distribution mesh 43, thus preventing channeling problems during coffee extraction. Even if a topspace forming step is added between steps S10 and S11, some coffee beans may stick to the bottom surface of the water distribution mesh 43, but the first tamping layer B1 formed in step S3 firmly blocks the flow of water, thus preventing channeling problems. Therefore, the topspace forming step can be performed between steps S10 and S11 or between steps S12 and S13.

[0068] The coffee flavor can differ between the case of extracting coffee after forming multiple tamping layers using the method described above and the case of extracting coffee after forming only one tamping layer, as shown in the table below.

[0069] Table 1

[0070] Compared with the prior art, in the case of the present invention, coffee extraction is achieved in multiple tamping layers through more than two feeding and tamping processes, thus increasing the concentration of coffee and enabling the extraction of rich coffee.

[0071] Furthermore, as the coffee's contact time with warm water increases, the coffee is extracted in different flavor profiles. The extraction proceeds in the order of acidity, sweetness, and bitterness. Acidity is extracted first, followed by bitterness as the contact time with warm water continues. In the first tamping layer B1, the longer contact time with warm water results in a coffee with a balanced flavor profile (acidity + sweetness + bitterness), while in the second tamping layer B2, the shorter contact time with warm water results in a coffee with a stronger acidity.

[0072] Furthermore, even if the tamping intensity during the first tamping is the same as "strongest", if the tamping intensity during the second tamping is different from "strong" and "weak", there will be a difference in sourness.

[0073] As described above, by performing multiple batching and tamping operations to form multiple tamping layers, the concentration of the extracted coffee can be increased. Furthermore, by making the tamping intensity lower during the second and subsequent tamping operations than during the first, a balanced flavor of the extracted coffee can be achieved, resulting in uniform coffee extraction. Moreover, by allowing the user to set the tamping intensity, various coffee flavors can be provided according to the user's taste.

[0074] As described above, the present invention has been described in detail through preferred embodiments, but the present invention is not limited to the above embodiments. Within the scope of the claims, the detailed description of the invention and the drawings, it can be implemented in various ways, and this also falls within the scope of the present invention.

Claims

1. An automatic coffee machine, comprising: Coffee bean storage box, used for storing coffee beans; The grinder module grinds coffee beans supplied from the coffee bean storage tank; An extractor module for feeding coffee beans pulverized in the grinder module; The tamping module tamps the crushed coffee beans stored in the extractor module; The coffee extraction port discharges liquid coffee extracted from the tamping module; The extractor module rotation drive unit causes the extractor module to rotate between the grinder module and the compaction module, so as to be opposite to the grinder module or opposite to the compaction module; and The control unit controls the process by performing the feeding and compaction multiple times.

2. The automatic coffee machine according to claim 1, characterized in that, In the multiple tamping processes, the tamping intensity during the first tamping is set to be the strongest.

3. The automatic coffee machine according to claim 2, characterized in that, In the multiple tamping processes, the tamping intensity after the second tamping is set to decrease as tamping progresses.

4. The automatic coffee machine according to any one of claims 2 or 3, characterized in that, The tamping intensity is determined by the number of revolutions per minute measured in the tamping motor.

5. The automatic coffee machine according to any one of claims 2 or 3, characterized in that, The compaction intensity is determined by the pressure measured by a sensor.

6. The automatic coffee machine according to claim 1, characterized in that, The tamping intensity performed in the tamping module is set by the user.

7. A coffee extraction method for an automatic coffee machine, comprising the following steps: Step a) The coffee beans are ground to a first volume in the grinder module and the ground coffee beans are contained in the extractor module for the first dispensing; Step b), drive the extractor module to rotate so that the extractor module is opposite to the tamping module; Step c), operate the tamping module to tamp the crushed coffee beans from the extractor module for the first time, thereby forming a first tamped layer; Step d), drive the extractor module to rotate so that the extractor module is opposite to the grinder module; Step e), the coffee beans are ground into a second volume in the grinder module, and the ground coffee beans are contained in the upper part of the first tamping layer of the extractor module for a second dispensing; Step f), drive the extractor module to rotate so that the extractor module is opposite to the tamping module; Step g), drive the tamping module and tamp the coffee beans housed in the extractor module a second time to form a second tamping layer on the first tamping layer; and Step h), supply water and extract liquid coffee.

8. The coffee extraction method for an automatic coffee machine according to claim 7, characterized in that, Between step c) and step d), a step is performed to determine whether to set the compaction intensity for the second compaction. If the judgment result is that the compaction strength for the second compaction is not set, then steps d) to g) are not executed, but step h) is executed instead. If the judgment result is that the compaction intensity for the second compaction has been set, then proceed with the steps following step d).

9. The coffee extraction method for an automatic coffee machine according to claim 7, characterized in that, Step h) includes a pre-infusion step of supplying water to coffee beans and waiting for a set time period.

10. The coffee extraction method for an automatic coffee machine according to claim 7, characterized in that, If the feeding and tamping are performed more than twice, after the last tamping, the tamping motor is driven in the opposite direction to the tamping and a top space is formed.

11. The coffee extraction method for an automatic coffee machine according to claim 7, characterized in that, The second capacity is constructed using a capacity smaller than the first capacity.

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