JP7508739B2 - Electric coffee maker - Google Patents

Description

To provide a drip-type electric coffee maker that can brew delicious coffee according to a user's preference by providing a flow path for a drip process and a flow path for a hot water addition process and controlling the amount of drip and the amount of hot water added.

FIG. 9 is an explanatory diagram of brewing a total of about 150 mL of coffee using about 10 to 12 g of ground coffee by dripping the first 1/3, the next 1/3, and the final 1/3.

The first 1/3 and the next 1/3 of the coffee are aromatic and delicious. However, the last 1/3 is weak like black tea, has a strong unpleasant taste, and is not tasty. Therefore, we developed a drip-type electric coffee maker that can brew coffee in a way that does not drip the untasty part in the latter half of the drip.

To brew one cup of coffee, an electric pump supplies and holds water for one cup in a boiler and boils it, after which the coffee is brewed by using a part of the water in a steaming process, a part of the water in a drip process, and the remaining water in a top-up process.

A flow path for the drip process that supplies hot water to the dripper and a flow path for the top-up process that supplies hot water directly to the coffee cup are provided, and the steaming process, drip process, and top-up process are carried out by controlling the opening and closing times of the solenoid valve to complete the entire process of brewing coffee. When all processes are completed, the hot water in the boiler is used up so that no hot water remains in the boiler.

The boiler has a volume large enough to hold one cup of water, and is provided with a water supply hole and a hot water supply hole C, and further with an exhaust hole to prevent pressure or negative pressure from being generated within the boiler.

When supplying a normal amount of water for one cup to the boiler, the operating time of the electric pump is controlled to supply water up to the normal water level of the boiler. However, in the event of an abnormality in which excessive water is supplied, a water level sensor is installed at the upper water level to prevent water from overflowing from the boiler, and when this sensor detects an abnormality, the electric pump is turned off to stop the water supply.

In this way, the present invention is a method for brewing one cup of coffee by controlling the opening and closing of solenoid valves that configure a flow path for the drip process and a flow path for the hot water addition process. Conventionally, two two-way solenoid valves were used to configure two flow paths, but we have invented a connection method and a control method for the solenoid valves that configure two flow paths using one two-way solenoid valve and one three-way solenoid valve, making it possible to perform the drip process and the hot water addition process.

In order to solve the above problems, the present invention provides an electric pump disposed between the water tank and the boiler, and arranges the boiler, buffer, dripper, and coffee cup vertically from top to bottom to facilitate natural falling of hot water.

A two-way solenoid valve C is connected to the hot water supply hole C of the boiler, and a three-way solenoid valve D is connected to the inlet port of the solenoid valve C, with one of the outlet ports connected to the buffer of the flow path for the drip stroke. The other outlet port is connected to the flow path for the hot water addition stroke, forming a flow path for the drip stroke and a flow path for the hot water addition stroke.

Since solenoid valve D is a three-way valve, the inlet port of solenoid valve D is always "open," and the outlet ports connected to the flow path for the drip stroke and the flow path for the top-up stroke are structured such that when either one of the outlet ports is "open," the other outlet port is switched to "closed."

By controlling solenoid valve C to "close" and controlling the operating time of the electric pump, the amount of water for one cup is supplied to the boiler and held there for boiling. To carry out the steaming process, solenoid valve C is controlled to "open" and the flow path for the drip process of solenoid valve D is controlled to "open" to supply the amount of water required for steaming to the dripper, and solenoid valve C is controlled to "close".

When the steaming process is complete, the drip process begins, and solenoid valve C is controlled to "open," and the flow path for the drip process of solenoid valve D is controlled to "open" to supply hot water to the dripper. When the amount of dripped coffee reaches 30-70% of the amount of coffee for one cup, solenoid valve C is controlled to "close," completing the drip process.

Next, the hot water refill stroke begins, and solenoid valve C is controlled to "open" to open the flow path for the hot water refill stroke of solenoid valve D, supplying hot water directly to the coffee cup to brew one cup of coffee. When the hot water refill stroke is completed, there is no residual hot water left in the boiler.

In this way, by controlling the operation timing and operation time of the electric pump, the solenoid valve C, and the solenoid valve D by the control circuit, the electric coffee maker can execute the steaming process, the drip process, and the hot water adding process, brew coffee with a drip amount of 30 to 70% of the amount of coffee required for one cup, and leave no hot water in the boiler when all the processes are completed.

As an application of the above-mentioned method of connecting solenoid valve C and solenoid valve D, there is a method of connecting solenoid valve D to the hot water supply hole C of the boiler, and connecting solenoid valve C to solenoid valve D. The inlet port of the three-way solenoid valve D is connected to the hot water supply hole C at the bottom of the boiler, and further, a two-way solenoid valve C is connected to one of the outlet ports of solenoid valve D, and the other outlet port is connected to a buffer for the drip stroke, thereby forming a flow path for the drip stroke and a flow path for the top-up stroke.

Since solenoid valve D is a three-way valve, the inlet port of solenoid valve D is always "open," and the outlet ports connected to the flow path for the drip stroke and the flow path for the top-up stroke are structured such that when either one of the outlet ports is "open," the other outlet port is switched to "closed."

The flow path for the drip stroke of solenoid valve C and solenoid valve D is controlled to "close" and the operating time of the electric pump is controlled to supply one cup's worth of water to the boiler and hold it there to boil water. To perform the steaming stroke, the flow path for the drip stroke of solenoid valve D is controlled to "open" to supply the amount of hot water required for steaming to the dripper, and the flow path for the drip stroke of solenoid valve D is controlled to "close".

When the steaming process is completed, the drip process begins, and the flow path for the drip process of solenoid valve D is again controlled to "open" to supply hot water to the dripper, and when the amount of dripped coffee reaches 30-70% of the amount of coffee for one cup, the flow path for the drip process of solenoid valve D is controlled to "close" to complete the drip process. Solenoid valve C remains in the "closed" state until the drip process is completed.

Next, the hot water addition process starts, and solenoid valve C is controlled to "open" to supply hot water directly to the coffee cup to brew one cup of coffee. When the hot water addition process is completed, there is no residual hot water left in the boiler.

In this way, by controlling the operation timing and operation time of the electric pump, the solenoid valve D and the solenoid valve C by the control circuit, the electric coffee maker can execute the steaming process, the drip process and the hot water adding process, brew coffee with a drip amount of 30 to 70% of the amount of coffee required for one cup, and leave no hot water in the boiler when all the processes are completed.

In the drip-type electric coffee maker of the present invention, the boiler, buffer, dripper, and coffee cup are arranged vertically from top to bottom, and a two-way solenoid valve C and a three-way solenoid valve D are used to form a flow path for the drip process and a flow path for the hot water addition process.The operation timing and operation time of the two solenoid valves are controlled, allowing coffee drip and hot water to be added by natural falling of hot water.

By controlling the operating time of the electric pump, the amount of water for one cup is supplied to the boiler and boiled, and by controlling the operating timing and operating time of two solenoid valves, the amount of drip is set to 30 to 70% of the amount of coffee in one cup, and the amount of added water is set to 70 to 30% of the amount of coffee in one cup, making it possible to avoid dripping the less tasty part in the latter half of the drip process and making delicious coffee.

When the drip process and the hot water addition process are completed in this manner, the amount of coffee in one cup is the sum of the amount of drip and the amount of hot water added, and the amount of water supplied to the boiler for one cup can be used up so that no hot water remains.

The following terms used herein have the following meanings:
The amount of coffee in one cup is the amount of coffee for one person, which is about 70-80% of the capacity of one cup, and is assumed to be 150 mL here. The amount of water for one cup is the amount of water required to brew one cup of coffee, and is the sum of the amount of coffee in one cup and the amount of hot water absorbed by the coffee powder. The capacity of one cup is the full capacity of a coffee cup, and is assumed to be 205 mL for a commercially available paper cup here.

Drip is the process of extracting coffee by pouring hot water over coffee powder. The drip amount is the amount of coffee dripped into a coffee cup. The added water amount is the amount of hot water poured directly from the boiler into the coffee cup.

The steaming process is a process in which hot water is supplied to the coffee grounds before the drip process to allow them to absorb enough water and steam. The drip process is a process in which hot water is supplied to the coffee grounds in the dripper to extract coffee, and the steaming process is also a part of the drip process. The hot water addition process is a process in which hot water is supplied directly to the coffee cup.

The normal water level of the boiler is the water level when one cup of water is filled into the boiler. The upper limit water level of the boiler is the maximum water level when limited by the water level sensor.

The configuration of the device 1 according to an embodiment of the present invention will be described below. Fig. 1 shows an embodiment showing the basic configuration of the present invention. The operation panel 2 of the device 1 is equipped with a power switch 3, a selection switch 4, and a start switch 5. The selection switch 4 allows the user to select the amount of drip coffee within the range of 30-100% of the amount of coffee in one cup.

A removable water tank 6 is located at the rear of the device, and a coffee cup 7 for receiving coffee can be placed at the front lower part. The dripper receiver 8 is removable, and a dripper 9 can be set by removing the dripper receiver 8. A paper filter 10 can be placed in the dripper 9, and coffee powder 11 can be added.

The water tank 6 and the boiler 12 are connected by a water supply pipe 14 via an electric pump 13. The boiler 12, the buffer 45, the dripper 9, and the coffee cup 7 are arranged vertically from top to bottom to allow the hot water to fall naturally.

2 and 3 show the components of the boiler 12. The boiler 12 is composed of a boiler vessel 17, a vessel lid 18, and a heater 19, and is equipped with a temperature sensor 20, a thermostat 21, and a temperature fuse 22. Furthermore, a water supply hole 23 and an exhaust hole 24 are provided in the vessel lid 18, and a hot water supply hole C42 is provided in the bottom of the boiler vessel 17.

A two-way solenoid valve C40 is connected to a hot water supply hole C42 provided at the bottom of the boiler 12, and an inlet port of a three-way solenoid valve D41 is further connected to the solenoid valve C40. Since the solenoid valve D41 is a three-way valve, the inlet port is always "open," and when either one of the outlet ports connected to the flow path for the drip stroke and the flow path for the top-up stroke is "open," the other outlet port is switched to "closed."

When supplying hot water to the flow path for the drip stroke, solenoid valve C40 controls the "open" time to supply hot water to solenoid valve D41, and when the outlet port on the flow path side for the drip stroke of solenoid valve D41 is "opened," hot water is supplied to dripper 9 via buffer 45, thereby executing the steaming stroke or drip stroke.

During the hot water addition stroke, solenoid valve C40 is controlled to be "open" to close the outlet port on the flow path for the drip stroke of solenoid valve D41, and the outlet port on the flow path for the hot water addition stroke is "open" to supply hot water directly to coffee cup 7.

The purpose of the exhaust hole 24 is to exhaust air so that no internal pressure is generated in the boiler 12 when supplying water, so that one cup's worth of water can be easily supplied, and to prevent steam pressure from being generated in the boiler 12 when boiling water.Furthermore, the purpose is to suck air in so that the boiler 12 does not become negative pressure when supplying hot water to the coffee cup 7.

Furthermore, the exhaust hole 24 is connected by an exhaust pipe 31 to an exhaust port 30 provided on the outer casing of the body 1 in order to exhaust the steam and steam pressure generated when boiling water outside the body, thereby preventing steam and water droplets from adversely affecting the components inside the body 1.

In order to prevent excessive water supply, the boiler 12 is provided with a water level sensor 27 and an upper water level 29 is set above the normal water level 28. When the water level sensor 27 detects the upper water level 29, it turns off the power supply to the electric pump 13 to stop the water supply.

An embodiment of the process of brewing coffee according to the present invention will now be described. Figure 8 shows an example of the operation panel 2. After pressing the power switch 3 to turn on the power, pressing the selection switch 4 to select a desired coffee, and then pressing the start switch 5, the electric pump 13 is operated and the operation time of the electric pump 13 is programmed so that the amount of water for one cup is supplied to the boiler 12. The amount of water for one cup is the amount of water supplied to the boiler vessel 17 up to the normal water level 28.

When one cup's worth of water has been supplied to the boiler 12, the electric pump 13 stops to maintain the amount of water, and the heater 19 installed inside the boiler 12 turns on to begin the water boiling process. When the water in the boiler 12 reaches 90-100°C, the temperature sensor 20 detects this and turns off the heater 19. Until this process, the solenoid valve C40 is in the "closed" state.

After the water temperature reaches 90 to 100°C and the heater 19 is turned off, the solenoid valve C40 opens and the hot water in the boiler 12 is supplied to the solenoid valve D41. The outlet port on the flow path for the drip stroke of the solenoid valve D41 opens and the steaming stroke begins, and the hot water is supplied to the dripper 9 via the buffer 45.

The amount of hot water for steaming is about 20 to 30 mL, which is sufficient to steam the coffee powder 11 in the dripper 9, and after the hot water is supplied, the solenoid valve C40 is closed. Steaming is continued for about 20 to 30 seconds.

Thereafter, the drip stroke begins, solenoid valve C40 opens again, the outlet port on the drip stroke flow path of solenoid valve D41 opens, hot water is supplied to dripper 9 via buffer 45, dripping begins, and coffee is extracted into coffee cup 7. At this time, if American or Goodtaste in Fig. 8 is selected with selection switch 4, the outlet port on the drip stroke flow path of solenoid valve D41 closes when about 30-70% of the amount of coffee for one cup has been dripped, and the outlet port on the hot water addition stroke flow path opens, entering the hot water addition stroke.

In the hot water addition process, hot water from the boiler 12 is supplied directly to the coffee cup 7 at about 70 to 30% of the amount of coffee for one cup. At this time, the outlet ports on the flow path for the hot water addition process of the solenoid valves C40 and D41 are "open" until the hot water in the boiler 12 runs out, and when the hot water in the boiler 12 runs out, the solenoid valve C40 is "closed" and the process of brewing one cup of coffee is completed.

When the selection switch 4 is set to Normal, 100% of the amount of coffee required for one cup can be dripped, making it possible to brew coffee without the need for additional hot water.

Furthermore, when Strong is selected with the selection switch 4, no additional water is added after about 30-70% of the amount of coffee for one cup is dripped in the drip process. Since no additional water is added, a strong espresso-like coffee can be brewed. At this time, only the amount of water required for 30-70% of the drip is supplied to the boiler 12 to boil the water.

In this manner, the process of brewing coffee is carried out by controlling the operation timing and operation time of the electric pump 13, solenoid valve C40 and solenoid valve D41 according to the program of the control circuit 36, in this drip-type electric coffee maker.

As an application of the method of connecting solenoid valve C40 and solenoid valve D41 in the above embodiment, there is a method of connecting the inlet port of solenoid valve D41 to hot water supply hole C42 of boiler 12, connecting solenoid valve C40 to one outlet port of solenoid valve D41, and connecting buffer 45 on the drip stroke flow path to the other outlet port as shown in Fig. 7. The operation timing and operation time of solenoid valve D41 and solenoid valve C40 can be controlled by the program of control circuit 36 to supply hot water to the drip stroke flow path or the top-up flow path.

As an application of the program of the above embodiment, there is a brewing method that omits the steaming step. In addition, in the order of the drip step and the hot water addition step, it is possible to perform the hot water addition step before the drip step. Furthermore, there is also a method of dividing the drip step into several times and dripping with an interval of several seconds.

Thus, in the present invention, the electric pump 13 and the solenoid valves C40 and D41 are controlled by the program of the control circuit 36, but there is a great deal of freedom in program design. Therefore, by changing the program, it is possible to first supply water for steaming to the boiler 12 to boil the water and perform the steaming process, or to supply water for dripping and adding hot water again to the boiler 12 during the steaming process to boil the water and perform the drip process and the adding hot water process.

Even when water is supplied to the boiler 12 in two separate portions in this way, the amount of water for one cup, that is, the amount of water required to brew one cup of coffee, is supplied to the boiler 12. At this time, it is also possible to set the water boiling temperature for the steaming process and the water boiling temperature for the drip process to different water temperatures.

1 is an example showing the configuration of basic parts and a housing of the present invention. 1 is an example of a vertical cross-sectional view of a boiler according to the present invention (cross-section A-A in FIG. 3). FIG. 2 is an example of a top view of a boiler of the present invention. 1 is an example of a vertical cross-sectional view of a conventional boiler (cross-section A-A in FIG. 5). 1 is an example of a top view of a conventional boiler. 1 is a diagram showing an example of a conventional configuration of basic parts and a housing; 1 is an application example of a method for connecting a solenoid valve according to the present invention. 2 is an example of an operation panel of the present invention. This is an explanatory diagram comparing the first 1/3 drip, the next 1/3 drip, and the last 1/3 drip when brewing one cup of coffee using a commercially available dripper.

REFERENCE SIGNS LIST 1 Body 2 Operation panel 3 Power switch 4 Selection switch 5 Start switch 6 Water tank 7 Coffee cup 8 Dripper tray 9 Dripper 10 Paper filter 11 Coffee powder 12 Boiler 13 Electric pump 14 Water supply pipe 15 Solenoid valve A 16 Solenoid valve B
17 Boiler vessel 18 Vessel lid 19 Heater 20 Temperature sensor 21 Thermostat 22 Temperature fuse 23 Water supply hole 24 Exhaust hole 25 Hot water supply hole A 26 Hot water supply hole B
27 Water level sensor 28 Normal water level 29 Upper water level 30 Exhaust port 31 Exhaust pipe 32 Hot water pipe A
33 Hot water pipe B 34 Hot water outlet A
35 Hot water outlet B 36 Control circuit 37 Check valve 38 Drip outlet 39 Cup holder 40 Solenoid valve C
41 Solenoid valve D 42 Hot water supply hole C
43 Hot water supply pipe C (flow path for drip process) 44 Hot water supply pipe D (flow path for adding hot water process)
45 Buffer

Claims (1)

In this device, an electric pump is placed between a water tank and a boiler, a boiler, a buffer, a dripper, and a coffee cup are placed vertically from top to bottom to allow hot water to fall naturally, an electromagnetic valve is placed between the boiler and the buffer to form a flow path for the drip process, and an electromagnetic valve is placed between the boiler and the coffee cup to form a flow path for the topping-up process, the operation time of the electric pump is controlled to supply and hold one cup's worth of water to the boiler for boiling, the boiled water is used for a steaming process by controlling the electromagnetic valve of the flow path for the drip process to supply the amount of hot water required for steaming to the dripper, and the steaming process is performed, in the drip process, the electromagnetic valve of the flow path for the drip process is controlled to supply hot water to the dripper, and when the amount of dripping reaches 30 to 70% of the amount of coffee in one cup, the electromagnetic valve of the flow path for the drip process is controlled to complete the drip process, and in the topping-up process, the flow path for the topping-up process is controlled. In this way, in a coffee maker that brews one cup of coffee by controlling the electric pump, the solenoid valve for the drip stroke, and the solenoid valve for the hot water addition stroke, when the amount of water for one cup is supplied to the boiler, first the amount of water for steaming is supplied to boil the water and the steaming stroke is performed, and then during or after the steaming stroke, the amount of water for drip and the amount of water for the hot water addition can be supplied to the boiler to boil the water, and the water is boiled at a temperature different from the water boiling temperature for steaming, and the drip stroke and the hot water addition stroke can be performed. The total amount of water supplied in multiple installments in this way is the amount of water for one cup, and when the steaming stroke, drip stroke, and hot water addition stroke are completed, no water supplied to the boiler remains. In this way, a drip-type electric coffee maker is equipped with a control circuit that controls how to brew coffee.

Images