JP3063541B2 - Coffee kettle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coffee machine having a coffee bean crusher.

[0002]

2. Description of the Related Art Conventionally, this kind of coffee machine is shown in FIG.
The configuration shown in FIG. Hereinafter, the configuration will be described with reference to FIG.

In the figure, 1 is a commercial AC power supply, 2 is a grinding chamber which accommodates coffee beans, and has a bottom provided with a hole large enough to allow ground coffee powder to pass through, and 3 is a grinding chamber for grinding coffee beans. The cutter is rotatably provided in the crushing chamber 2. Reference numeral 4 denotes a motor for rotating the cutter 3. Reference numeral 5 denotes a filtration chamber provided below the crushing chamber 2 for setting a paper filter and storing crushed coffee powder. Reference numeral 6 denotes a water container for containing water for extracting coffee liquid. Reference numeral 7 denotes a heater that heats water in a water pipe 7a having one end connected to the bottom of the water container 6. Reference numeral 8 denotes a coffee container which stores coffee liquid dropped from the filtration chamber 5. Reference numeral 9 denotes a switching unit for switching between energization of the motor 4 and the heater 7, and the timing of the switching operation is set by a timer 10.

The operation of the above configuration will be described. An appropriate amount of coffee beans is put into the crushing chamber 2, and the time of the timer 10 is set in accordance with a preset reference time scale according to the amount of coffee beans. When the timer 10 starts operating, the switching means 9 switches to the motor 4 side, the motor 4 is operated, the cutter 3 rotates, and the coffee beans stored in the grinding chamber 2 are ground. The ground coffee powder passes through a hole provided at the bottom of the grinding chamber 2 and is stored in a paper filter of a filtration chamber 5 provided below the grinding chamber 2. When the time set by the timer 10 elapses, the switching means 9 switches to the heater 7 side,
The heater 7 is energized to heat the water in the water pipe 7a.
A check valve 7b is provided at the connection between the water pipe 7a and the water container 6, and the hot water heated in the water pipe 7a does not flow back into the water container 6 due to the pressure of the partially evaporated steam. From the other end of the water pipe 7a opening at the top of the crushing chamber 2
To be dropped. The hot water flows into the filtration chamber 5 through a hole provided at the bottom of the grinding chamber 2 while washing away the coffee powder remaining in the grinding chamber 2. When dripping for a predetermined time, the switching means 9 switches to the OFF side once, and steams the coffee powder for a predetermined time. Thereafter, the switching means 9 is switched to the heater 7 side, all the water in the water container 6 is poured into the coffee powder in the filtration chamber 5, and the coffee liquid is dripped from an opening provided at the bottom of the filtration chamber 5 so that the coffee container is dropped. 8

[0005]

In the coffee brewing apparatus having such a conventional configuration, when the timer time is set in accordance with the amount of beans, the time is set according to a scale provided in advance, so that it is difficult to grind. In the case of lightly roasted beans, the timer time expires during the pulverization of the beans, and conversely, in the case of deeply roasted beans that are easy to pulverize, the motor continues to operate even though the beans are all pulverized, There is a problem that wasteful electric power is consumed and the noise of the idling motor is uncomfortable.

To cope with such a problem, there is known a configuration in which a motor current that changes at the end of grinding of coffee beans is detected, and the completion of the grinding is detected based on a current change rate or a set current value to stop the motor. I was

However, in such a configuration, the end of the grinding cannot be detected with high accuracy unless the accuracy of the detection circuit is increased in consideration of the variation in the motor output, the motor power supply voltage, and the state of the load. There was a problem.

[0008] The present invention solves the above-mentioned problems, and reliably rotates the motor until the entire amount of coffee beans is ground,
It is a first object of the present invention to provide a coffee brewing device that stops the rotation of the motor immediately after the whole amount has been pulverized and starts the coffee extraction.

Next, in the conventional coffee machine, even if the timer is started with no coffee beans in the grinding chamber, the motor rotates for the time set by the timer. There was a problem that the hot water was stored in the coffee container despite the fact that there was no hot water.

A second object of the present invention is to provide a coffee brewing machine which stops the operation promptly when the motor rotates in a state where no coffee beans are contained in the crushing chamber. The purpose is.

It is a third object of the present invention to notify the user of forgetting to put beans by a notification sound and to prevent the notification sound from being canceled by the noise of the motor, thereby more surely notifying the user of the abnormality.

[0012] Next, if the beans rotate too simultaneously with the cutter while being sandwiched between the cutter and the inner wall of the crushing chamber due to too much beans entering the crushing chamber, erroneous determination by the crushing end detecting means is made when abnormal vibration occurs. It is a fourth object to avoid it.

Next, in the case where the beans are temporarily clogged repeatedly or when the pulverization continues to clearly exceed the maximum amount, the power supply to the motor is stopped to allow the motor to operate for a long time. A fifth object is to prevent a reduction in life due to operation.

Next, in the conventional coffee kettle, the hot water necessary for steaming is discharged by the switching means. However, the amount of hot water to be discharged is always constant because the power supply time of the heater is constant. Although it is an appropriate amount for steaming coffee powder, in the case of 5 cups, hot water cannot be completely soaked. On the other hand, there is a problem that the amount is appropriate for steaming 5 cups of coffee powder, but in the case of 1 cup, the amount of hot water is too large, so that the extraction starts immediately.

A sixth object of the present invention is to solve the above-mentioned problems, and it is a sixth object of the present invention to provide a coffee kettle capable of steaming with an appropriate amount of hot water corresponding to the amount of coffee powder.

A seventh object is to reduce the cost by using the piezoelectric element not only as a vibration detecting element but also as a notification element.

[0017]

A first means for solving the first object is a cutter for crushing coffee beans, a crushing chamber in which the cutter is housed, and a motor for driving the cutter. Motor control means for operating / stopping the motor, heating control means for discharging hot water to coffee powder crushed and stored in the filtration chamber to extract coffee liquid, and controlling the motor current for a first predetermined time Current detecting means for measuring each time, the crushing chamber when crushing coffee beans, and a vibration detecting element for converting vibration during rotation of the motor into an electric signal, and amplifying and waveform of an output signal of the vibration detecting element. Measuring the signal of the vibration waveform processing means at every second predetermined time, calculating the difference between the maximum value and the minimum value of the measurement value at every third predetermined time, and calculating the difference Is the first At a point in time when the state of being equal to or less than the predetermined value is continued for a predetermined number of times, if the current value measured by the current detection means is within a predetermined range, the motor control means stops energization of the motor and operates the heating control means. This is configured to include a pulverization end detection unit.

A second means for solving the second object is to measure a signal of the vibration waveform processing means in addition to the first means just before starting the motor operation and at every fourth predetermined time from the start of the motor operation. When the difference from the previous measured value is equal to or more than a second predetermined value, the pulverization end detecting means is operated, and the state in which the difference from the previous measured value is smaller than the second predetermined value is the fifth state. If the current value measured by the current detecting means is equal to or more than the third predetermined value at the time when the predetermined time has elapsed, the load detecting means for stopping the motor by the motor controlling means is provided.

A third means for solving the third object is that, in addition to the first means, after the motor control means stops the energization of the motor in accordance with the instruction of the load detecting means, a predetermined motor self-control is performed. And a no-load notifying unit for notifying when the noise of the motor is reduced by the inertia force.

A fourth means for solving the fourth object is that, in addition to the first means, the pulverization end detecting means determines a difference between a maximum value and a minimum value per third predetermined time by a first predetermined value. When it is determined that the state of being equal to or less than the predetermined value has continued for the predetermined number of times, and if the minimum value during that time is equal to or more than the fourth predetermined value, the determination of the pulverization end detection means is invalidated, and an instruction to perform the determination again is issued. This is a configuration provided with vibration detection means.

A fifth means for solving the fifth object comprises, in addition to the first means, a maximum value and a minimum value obtained by the pulverization end detecting means when a sixth predetermined time has elapsed from the start of the motor operation. If the difference between the values is equal to or greater than a first predetermined value, the motor control means stops the motor and the apparatus is provided with abnormal crush detection means.

A sixth means for solving the sixth object is that, in addition to the first means, the time from the start of the motor operation to the motor control means stopping the energization of the motor by the pulverization end detecting means is measured. The heating control means is operated for a time corresponding to the time, thereby providing a steaming control means for increasing or decreasing the amount of hot water for steaming the coffee powder stored in the filtration chamber.

A seventh means for solving the seventh object is provided with a notification control means for applying a rectangular voltage waveform to the vibration detecting element and generating a notification sound.

[0024]

In the above arrangement, according to the first means, the crushing end detecting means measures the signal of the vibration waveform processing means and calculates the difference between the maximum value and the minimum value of the value per a third predetermined time. If the current value measured by the current detecting means is within a predetermined range at a point in time when the state in which the difference is equal to or less than the first predetermined value continues for a predetermined number of times, it is determined that the motor is idling with no load. After the determination, the motor control means stops the current supply to the motor, and the heating control means starts the current supply to the heater. Thus, the end of the grinding of the coffee beans is detected, the operation of the motor is stopped, and the extraction of coffee is started.

According to the second means, the load detecting means measures the signal of the vibration waveform processing means immediately before the start of the motor operation and at every fourth predetermined time from the start of the motor operation, and the difference from the previous measured value is measured. When the value is equal to or more than the second predetermined value, the start of the measurement is instructed to the pulverization end detection means, and the state in which the value is less than the second predetermined value is changed to the fifth value.
If the current value measured by the current detection means is equal to or more than the third predetermined value at the time point when the predetermined time has elapsed, it is determined that the beans have not been crushed even once since the start of the motor operation, and the motor control means Is stopped. This allows
When the coffee beans are put, the grinding is continued, and when the coffee beans are not put, no load is detected and the operation of the motor is stopped.

According to the third means, when there is an instruction from the load detecting means, the no-load notifying means notifies when a predetermined time elapses. Thus, when the noise of the motor is reduced, the user is more reliably notified of the abnormality.

According to the fourth means, the pulverization end detecting means measures the vibration waveform of the vibration waveform processing means, and the difference between the maximum value and the minimum value per the third predetermined time is equal to or less than the first predetermined value. When it is determined that the state has continued for a predetermined number of times, the abnormal vibration detecting means determines that the minimum value during that time is equal to or greater than a fourth predetermined value.
The determination by the pulverization end detection means is invalidated, and an instruction is made to perform the determination again. Thus, abnormal vibration when the beans are not crushed properly is detected, and erroneous determination by the crushing end detecting means can be avoided.

According to the fifth means, the abnormal pulverization detecting means determines the difference between the maximum value and the minimum value by the pulverization end detecting means at the time when the sixth predetermined time has elapsed from the start of the motor operation.
If the value is equal to or more than the predetermined value, the motor control means stops the energization of the motor. This avoids a state in which the beans are temporarily clogged repeatedly, and prevents the motor from operating for a long time due to pulverization that exceeds the rated maximum amount.

According to the sixth means, the steaming control means measures the coffee bean pulverization time from the start of the motor operation to the pulverization end detection means, and operates the heating control means according to this time. As a result, the heater is energized for the time determined according to the measured time, and steaming is performed with the amount of hot water corresponding to the amount of coffee powder.

According to the seventh means, the notification control means applies a rectangular voltage waveform to the vibration detecting element to sound a notification sound. Thereby, the vibration can be detected by one vibration detecting element and the notification can be performed.

[0031]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to FIGS.

The same parts as those shown in the conventional example are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, reference numeral 11 denotes a heating control means for controlling ON / OFF of energization to the heater 7.
Reference numeral 12 denotes a motor control unit which turns on / off the energization of the motor 4.
FF control is performed. Reference numeral 13a denotes a vibration detecting element which receives vibrations of the crushing chamber 2 and the motor 4 and outputs a voltage corresponding to the magnitude of the vibration. Numeral 14 is a vibration waveform processing means for amplifying the output signal waveform of the vibration detecting element 13a by a half-wave and smoothing it with a time constant of about 9.4 s. Reference numeral 15 denotes a current detecting means, which amplifies the current waveform of the motor 4 by half-wave and
The peak value is held every s. Reference numeral 16 denotes a crushing end detecting means, the operation of which will be described with reference to FIGS.

FIG. 2 shows a vibration signal waveform by the vibration waveform processing means 14. FIG. 3 shows a value obtained by the pulverization end detecting means 16 which measures the signal every 10 ms and calculates a difference between a maximum value and a minimum value every 1 second. It is a transition of. First, in FIG. 2, when power is supplied to the motor by the motor control means at time t0 and comminution starts, the waveform rises instantaneously due to the vibration of the motor 4 and the comminution chamber 2. Thereafter, the waveform changes constantly. Time t
At time 1, the difference between the maximum value and the maximum value between t0 and t1 is determined. At time t2, the difference between the maximum value and the minimum value between t1 and t2 is determined, and the same is repeated thereafter. Time t5
When all the beans are crushed at the point of time, only the stable vibration due to the idling of the motor thereafter occurs, the waveform becomes close to zero, and the difference after time t6 in FIG. 3 also approaches zero. FIG. 4 shows the current detecting means 15.
At time t0, and then becomes a load current during idling at time t5.

The first means is that, in FIG. 3, at time t6 when the difference between the maximum value and the minimum value becomes equal to or less than the threshold value 1 and at time t10 when the state continues for 4 seconds, the current value of FIG. Is within the range between the threshold value 2 and the threshold value 3, the end of the pulverization is detected. The threshold value 1 can be easily set because of the large difference in vibration between the time of grinding and the time of idling. Can be easily set without taking into account. In this embodiment, the threshold value 1 is 0.5 V, the threshold value 2 is 1.7 V, and the threshold value 3 is 0.1 V with respect to the maximum measurable value 5 V. When it is detected that the grinding of the coffee beans has been completed, the motor control means 12 stops the power supply to the motor 4 and the heating control means 11 starts the power supply to the heater 7. The hot water heated by the heater 7 is discharged to the crushing chamber 2 in the same manner as in the conventional example, poured into the coffee powder in the filtration chamber 5 and converted into a coffee liquid and stored in the coffee container 8.

As described above, according to the present embodiment, the difference between the vibration at the time of pulverization and the vibration at the end of pulverization is detected by the pulverization completion detection means 16 and the motor lock or disconnection state, which cannot be determined only by the vibration, is detected by current detection. By performing the detection by the means 15, the respective configurations and settings can be simplified, and the end of the pulverization can be detected with high accuracy.

(Embodiment 2) Next, FIG.
This will be described with reference to FIG. In FIG. 5, reference numeral 17 denotes a load detecting means, and FIG. 6 shows the vibration signal waveform of the vibration waveform processing means 14 measured by the load detecting means 17. First, at time t00 immediately before the start of the motor operation, the first measurement is performed and used as initial data, and the motor control means starts energizing the motor. Time t 80 ms after t00
At the time of 01, the second measurement is performed and the difference from the initial data is obtained. If the difference is equal to or more than the predetermined value, it is determined that the beans are being ground, the subsequent measurement is stopped, and the start of the measurement is instructed to the grinding end detecting means 16. If the difference is equal to or smaller than the predetermined value, the third measurement is performed at time t02 80 ms after t01, and the difference from the data at time t01 is obtained. Thereafter, if the difference is equal to or smaller than the predetermined value, the same is repeated. When the current measured value by the current detecting means 15 is equal to or larger than the threshold value 3 at the time when the maximum time tmax is reached from the time t00, beans are not inserted. It is determined that there is no
By 2, the energization of the motor 4 is stopped, and the subsequent extraction operation is stopped. In this embodiment, the predetermined value is ± 0.8 V, tma
x is variably set to 0.3 s to 4 s, and the difference when there is no bean is usually ± 0.1 V or less.

As described above, according to this embodiment, the presence / absence of beans can be instantaneously and accurately detected by causing the load detecting means 17 to detect the rise of the vibration signal at the time of crushing.

(Embodiment 3) Next, FIG.
This will be described with reference to FIG. In FIG. 7, reference numeral 18 denotes a no-load notifying means. The no-load notifying means 18 waits for a predetermined time and waits for a predetermined time after the load detecting means 17 determines that there is no bean and stops supplying power to the motor 4 by the motor control means 12. Notify that. According to the present embodiment, the motor is hardly rotated when waiting for 2 seconds, and the notification is performed in a state of low noise.

As described above, according to this embodiment, by controlling the timing of the notification by the no-load notification means 18, it is possible to more reliably notify the user of forgetting to insert beans.

(Embodiment 4) Next, FIG.
This will be described with reference to FIG. When a signal indicating that the pulverization of beans has been detected is received from the pulverization completion detection means 16, an abnormal vibration detection means 19 is provided for confirming the pulverization state and determining whether the signal is valid or invalid. The operation will be described with reference to FIG.

FIG. 9 shows the vibration by the vibration waveform processing means 14 when the beans are rotated simultaneously with the cutter 3 in a state where the beans are sandwiched between the cutter 3 and the inner wall of the grinding chamber 2 because the beans too much enter the grinding chamber 2 during the grinding. FIG. 10 shows signal values measured by the pulverization end detecting means 16. In this example, since the beans start to rotate at the same time as the cutter 3 at the time t4 and the pulverization is not performed normally, the difference between the maximum value and the minimum value is equal to or less than the threshold value 1 and the pulverization end detection means 16 detects the end at time t9. This is because the vibration at the time of abnormal pulverization is much larger than usual, so that the maximum measurable value was cut off, and the difference between the maximum value and the minimum value was compressed. The abnormal vibration detecting means 19 compares the minimum measurement value between the time t5 and t9 when the crushing end detecting means 16 detects the end with the threshold value 4 to detect the abnormal crushing. It is determined that the pulverization is abnormal, and the pulverization end detection means 16 is instructed to perform the end detection again.

As described above, according to the present embodiment, erroneous determination by the crushing end detecting means 16 can be avoided by causing the abnormal vibration detecting means 19 to detect the vibration at the time of abnormal crushing.

(Embodiment 5) Next, FIG.
1 will be described. In FIG. 11, reference numeral 20 denotes an abnormal crush detection means. When the motor control means 12 starts energizing the motor, the abnormal crush detection means 20 starts time measurement, and when a predetermined time has elapsed, the crush end detection means 1
The latest data of the difference between the maximum value and the minimum value according to 6 is read.
If the latest data is equal to or smaller than the threshold value 1, the data is continuously read until the difference data becomes equal to or larger than the threshold value 1. If the difference data is greater than or equal to the threshold value 1, the motor control means 1
The power supply to the motor is stopped by 2 and the user is notified of the abnormal grinding time by a notification sound. Normally, the time required for grinding 5 cups of beans is about 40 s at maximum, and in this embodiment, the time is set to 1 minute.

As described above, according to the present embodiment, the life of the motor can be extended by preventing the motor from operating for a long time by the abnormal crush detection means 20.

(Embodiment 6) Next, FIG.
This will be described with reference to FIG. In FIG. 12, reference numeral 21 denotes a steaming control unit, which measures the time from the start of energization of the motor 4 by the motor control unit 12 to the end of the pulverization by the pulverization end detection unit 16, and according to the time required for the pulverization, the heating control unit 11 The heater 7 is energized for a predetermined time to discharge the amount of hot water necessary for steaming. In this embodiment, when the measured grinding time is less than 17 s,
The energization time of the heater 7 is set to 7.2 s, 12 s, and 21 s when the time is 8 s or more and less than 27 s, and when it is 27 s or more.
Is controlled as As a result, the coffee powder becomes 1-2
The amount of hot water to be discharged is about 20 cc to 30 cc for a cup, about 55 cc to 60 cc for 3 cups, and about 95 to 110 cc for 4 to 5 cups.

As described above, according to the present embodiment, the amount of coffee powder can be grasped by detecting the pulverization time of the beans by the steaming control means 21, and steaming is performed with the amount of hot water corresponding to the amount. Coffee can be extracted.

(Embodiment 7) Next, FIG.
3 will be described. In FIG. 13, a piezoelectric buzzer is used for the vibration detecting element 13b, and a printed circuit board having its terminals soldered is mounted on the support plate of the motor 4 so as not to lower the sound pressure. In this configuration, the notification control unit 22 prohibits notification when the motor 4 is energized by the motor control unit,
When the motor 4 is not energized, a rectangular voltage waveform of 4 kHz is applied to the vibration detecting element 13b as necessary, so that a notification sound is emitted.

As described above, according to the present embodiment, a single piezoelectric element can be used for both vibration detection and notification by the notification control means 22, and cost can be reduced.

[0050]

As is apparent from the above embodiment, according to the first means, the provision of the pulverization end detecting means enables
The detection of the end of the grinding of the coffee beans can be performed with high accuracy with a simple configuration, the operation of the motor can be stopped immediately, and the extraction of coffee can be started.

In the second means, the presence of the beans can be instantaneously detected at the time of starting the motor by providing the load detecting means.
When the absence of beans is detected, the operation of the motor is immediately stopped, and the coffee extraction operation is stopped, so that coffee can be extracted without failure.

In the third means, by providing the no-load notification means, it is possible to more reliably notify the user that he has forgotten to insert beans.

In the fourth means, since the abnormal vibration detecting means is provided, it is possible to detect an abnormal vibration caused by too much beans in the pulverizing chamber, thereby avoiding erroneous determination by the pulverizing end detecting means. .

In the fifth means, since the abnormal crush detection means is provided, the motor can be prevented from operating for a long time due to the abnormal crush state, and the life of the motor can be extended.

In the sixth means, since the steaming control means is provided, steaming can be performed with an appropriate amount of hot water corresponding to the amount of coffee powder, so that more delicious coffee can be extracted.

In the seventh means, since the notification control means is provided, the piezoelectric element can be used for both the vibration detection and the notification, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a coffee brewer according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a vibration signal waveform by a vibration waveform processing unit.

FIG. 3 is a diagram showing an example of measured values obtained by a pulverization end detection unit

FIG. 4 is a diagram showing an example of a current measurement value by a current detection unit.

FIG. 5 is a configuration diagram showing a coffee brewer according to a second embodiment of the present invention.

FIG. 6 is a diagram showing an example of a measured value by a load detecting unit.

FIG. 7 is a configuration diagram illustrating a coffee brewer according to a third embodiment of the present invention.

FIG. 8 is a configuration diagram illustrating a coffee brewer according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing an example of a vibration signal waveform by the vibration waveform processing means at the time of abnormal grinding.

FIG. 10 is a diagram showing an example of measured values obtained by a pulverization end detecting unit in abnormal pulverization.

FIG. 11 is a configuration diagram illustrating a coffee brewer according to a fifth embodiment of the present invention.

FIG. 12 is a configuration diagram illustrating a coffee brewer according to a sixth embodiment of the present invention.

FIG. 13 is a configuration diagram illustrating a coffee brewer according to a seventh embodiment of the present invention.

FIG. 14 is a block diagram showing a conventional coffee machine.

[Explanation of symbols]

 2 Crushing chamber 4 Motor 5 Filtration chamber 11 Heating control means 12 Motor control means 13a, 13b Vibration detection element 14 Vibration waveform processing means 15 Current detection means 16 Crushing end detection means 17 Load detection means 18 No load notification means 19 Abnormal vibration detection means Reference Signs List 20 abnormal grinding detection means 21 steaming control means 22 notification control means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-110217 (JP, A) JP-A-4-354913 (JP, A) JP-A-63-98133 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) A47J 31/42

Claims (7)

(57) [Claims] 1. A cutter for crushing coffee beans, a crushing chamber in which the cutter is housed, a motor for driving the cutter, a motor control means for operating and stopping the motor, and a crushed and filtered chamber. Heating control means for discharging hot water to the contained coffee powder to extract the coffee liquid,
Current detecting means for measuring the motor current at every first predetermined time; the grinding chamber for grinding coffee beans; and a vibration detecting element for converting vibration during rotation of the motor into an electric signal; A vibration waveform processing means for amplifying and waveform processing the output signal of the sensing element; and measuring a signal of the vibration waveform processing means at every second predetermined time, and determining a difference between a maximum value and a minimum value of the measured value into a third value. Calculated at every predetermined time, and when the state where the difference is equal to or less than the first predetermined value continues for a predetermined number of times, if the current value measured by the current detection means is within a predetermined range, the motor control means A coffee brewing machine comprising: a crushing end detecting means for stopping power supply to a motor and operating the heating control means. 2. A signal of the vibration waveform processing means is measured immediately before the start of the motor operation and at every fourth predetermined time from the start of the motor operation, and when a difference from the previous measured value is equal to or more than a second predetermined value, When the state in which the difference from the previous measurement value is less than the second predetermined value continues until the fifth predetermined time, the current value measured by the current detection 2. A coffee brewing machine according to claim 1, further comprising a load detecting means for stopping the motor by the motor control means if the value is equal to or more than the predetermined value of 3. 3. The motor control means stops power supply to the motor in response to an instruction from the load detection means, and then waits for a time to continue idling by a preset inertia force of the motor itself, and notifies when the noise of the motor decreases. 2. A coffee brewing machine according to claim 1, further comprising a no-load notification means for performing the following. 4. When the crushing end detecting means determines that the state in which the difference between the maximum value and the minimum value per the third predetermined time is equal to or smaller than the first predetermined value has continued for a predetermined number of times, the minimum value during the period is determined. The method according to claim 1, further comprising an abnormal vibration detection means for invalidating the determination by the pulverization end detection means when the value is equal to or more than the fourth predetermined value and instructing the determination to be performed again. Heater. 5. When the difference between the maximum value and the minimum value detected by the pulverization end detecting means is equal to or greater than a first predetermined value at a point in time when a sixth predetermined time has elapsed from the start of motor operation, the motor is stopped by the motor control means. The coffee brewing machine according to claim 1, further comprising an abnormal crush detection means for causing the crushing. 6. A filter chamber is measured by measuring the time from the start of motor operation until the motor control means stops energizing the motor by the crushing end detecting means, and operating the heating control means for a time corresponding to the measured time. 2. A coffee boiler according to claim 1, further comprising steaming control means for increasing or decreasing the amount of hot water for steaming the obtained coffee powder. 7. The coffee brewing apparatus according to claim 1, further comprising a notification control means for applying a rectangular voltage waveform to the vibration detecting element and generating a notification sound.