JPH062106B2 - Coffee mill - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a mill mechanism driven by a motor, in particular, to crush coffee beans in a crushing case and sequentially store coffee powder generated by the crushing in a case. The present invention relates to a coffee mill including a mill mechanism adapted to be housed.

[Technical Background of the Invention and Problems Thereof] Conventionally, in this type of coffee mill, the energization time of the motor for driving the mill mechanism, that is, the mill time is controlled by a mechanical or electronic timer. It is configured.
With such a configuration, the time until all the coffee beans in the crushing case are crushed and the time until all the produced coffee grounds are stored in the storage case are the amount of coffee beans to be milled, It varies greatly depending on the type, freshness, roasting state, storage state, etc. Therefore, the user must consider the set time every time the mill time is set by the timer. However, it is actually extremely difficult to set the set time of the timer to the optimum, so that the operation time of the motor is insufficient and coffee beans or coffee grounds are left in the crushing case, and vice versa. There is a problem that the time becomes excessive and wasteful power is consumed.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object thereof is to reduce a mill time by a mill mechanism configured to sequentially store coffee powder generated in a crushing case in a storage case. The coffee beans or coffee powder can be automatically controlled in the crushing case so that the optimum time can be adjusted according to the amount, type, freshness, roasting state, storage state, etc. of the coffee beans stored in the crushing case. A coffee that can be left unattended and that the motor energization time is too long to consume useless power, so that anyone can use it very easily and properly without requiring skill. To serve the mill.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention is provided with a mill mechanism that crushes coffee beans in a crushing case and sequentially stores coffee powder generated by the crushing in a storage case. In a coffee maker, constant current detection that outputs a detection signal when the load current of the motor detected by a current detector stabilizes at a constant value by a switch means for controlling the current flowing through the motor for driving the mill mechanism. The switch means is turned on to start energizing the motor in response to the operation of the means and the mill operation start switch, and when the detection signal is output thereafter, the switch means is turned off to disconnect the motor. The control means is provided so that all the coffee beans stored in the grinding case are ground and stored. The power supply to the motor is automatically stopped when the motor is housed in the base.

[Examples of the Invention] Examples of applying the present invention to a coffee maker will be described below.

The fourth showing the overall structure of the coffee maker and the structure of the main parts
In FIG. 5 and FIG. 5, 1 is a coffee maker body,
A cartridge-type water storage tank 2 is provided on the left side of the drawing, and a heating table 3 is provided on the lower right side. A heater (indicated by reference numeral 27 in FIG. 1) is provided in the heating table 3.
A well-known hot water generating mechanism including a heating pipe (not shown) is provided, and the water in the water storage tank 2 is supplied into the heating pipe to be turned into hot water. Reference numeral 4 denotes a bottle placed on the heating table 3, and 5 denotes a cup-shaped extractor which is a storage case disposed above the bottle 4, and which has a hooking hole portion 6 (see FIG. 5) formed on the outer periphery of the upper end thereof. (See FIG. 5) is inserted into a projecting piece 7 (see FIG. 5) formed in a rising shape on the coffee maker main body 1 so as to be detachably attached thereto. Such an extractor 5
An extraction port 8 is formed at the bottom of the valve, and a valve device 9 for opening and closing the extraction port 8 is provided. When the extractor 5 is attached to the coffee maker main body 1, the valve device 9 comes into contact with the bottle lid 4 a that covers the bottle 4 and is in an open state. Reference numeral 10 denotes a vertical axis type motor arranged in the coffee maker body 1 at the left side of the extractor 5 in the drawing, and a case mounting portion 11 is formed above the motor 10. Reference numeral 12 is a crushing case detachably attached to the case attaching portion 11. The crushing body 13 rotatably driven by the motor 10 is provided on the inner bottom portion of the crushing case 12, and thus the milling mechanism 14 is constituted by these. A powder filter portion 12a (see FIG. 5) is provided by forming a large number of fine holes on the right side of the crushing case 12,
The powder filter portion 12a faces the upper opening of the extractor 5. Reference numeral 15 is a hood portion for guiding the coffee powder from the powder filter portion 12a into the extractor 5, one end of which surrounds the upper portion and both side portions of the powder filter portion 12a, and the other end portion of which is the upper surface of the extractor 5. It extends near the center of the opening. The hood portion 15 is formed in a substantially arcuate shape which is separated from the crushing case 12 toward the lower side, and the tubular hot water receiving portion 1 is provided on the upper surface portion.
6 are integrally formed, and a plurality of pouring holes 17 are formed in the inner area of the hot water receiving portion 16. Reference numeral 18 denotes a lid portion that covers the outer side portion of the hood portion 15 in the upper surface opening portion of the extractor 5, and a cylindrical portion 19 that is inserted into the inner peripheral portion of the upper end of the extractor 5 is integrally formed on the lower surface thereof. There is. Then, the upper end portion of the paper filter 20 housed in the extractor 5 has the extractor 5 and the tubular portion 19
It is sandwiched between and held. The hood portion 15 and the lid portion 18 configured as described above are integrally provided on the crushing case 12. In addition, 21 is the hot water receiving part 1
6 is rotatably provided above 6, and hot water generated by the heating pipe of the hot water generating mechanism is discharged from the hot water supply port body 21 into the hot water receiving portion 16. Reference numeral 22 is a cap detachably attached to the upper surface of the crushing case.

In order to extract the coffee liquid by the coffee maker having such a configuration, first, the coffee beans for the number of people are stored in the crushing case 12, and a predetermined amount of water is stored in the water storage tank 2, and then, as shown in FIG. Set to the state shown. Then, when the motor 10 is energized, the mill mechanism 14 is driven and the crushing of the coffee beans by the crushing body 13, that is, the milling operation is started. As a result, the coffee powder thus generated jumps out of the powder filter portion 12a by centrifugal force when the particle size becomes equal to or smaller than the fine pores of the powder filter portion 12a. The coffee powder that has jumped out is guided by the arc-shaped hood portion 15 while being extracted.
It falls on the paper filter 20 inside. In this case, the hood portion 15 having the function of introducing the coffee powder generated in the crushing case 12 into the extractor 5 has an extremely simple structure and connects the crushing case 12 and the extractor 5 at a substantially shortest distance. Therefore, the amount of coffee powder that adheres to the hood portion 15 and is not recovered in the extractor 5 is small, and the coffee powder recovery rate is high. Further, since the outer portion of the hood portion 15 of the upper surface opening portion of the extractor 5 is covered with the lid portion 18,
Even if the wind generated in the crushing case 12 by the rotation of the crushing body 13 blows into the extractor 5, the wind causes the extractor 5 to move.
The lid 18 prevents the coffee powder inside from being blown out of the extractor 5. After crushing all the coffee beans in this way and then energizing the heater 27 (see FIG. 3) of the hot water generating mechanism, the water in the water storage tank 2 is sequentially turned into hot water, and the hot water supply port body 21 to the hot water receiver 16 It is discharged into the inside of the hood portion 15 from the pouring hole 17 and dropped onto the coffee powder on the paper filter 20. The dropped hot water permeates the coffee powder to extract the coffee extract from the coffee powder, is filtered by the paper filter 20 and is dripped and stored in the bottle 4 from the extraction port 8 as described above. Then, the drip operation is performed.

FIG. 1 shows a circuit configuration of a control device provided in the coffee maker, which will be described below. However, it goes without saying that the functions of the respective blocks shown in the circuit configuration of FIG. 1 may be obtained by a program of a microcomputer as needed. Now, the motor 10 is connected to both ends of the commercial AC power supply 23.
A motor drive switch 24, which is a switch means, is connected in series, and a current transformer 25, which is a current detector for detecting the load current of the motor 10, is interposed in the energizing path of the motor 10. Further, a thermostat 26 for detecting the temperature of the heating table 3, the heater 27, and
A series circuit of a temperature fuse 28 and a heater drive switch 29 is connected. A DC power supply circuit 30 is supplied with power from the power supply 23 through the step-down transformer 31, and power is supplied to each circuit section described below from its output lines La and Lb.

That is, 32 is a differentiating circuit composed of a capacitor 33 and a resistor 34, which outputs an initialization pulse P ₀ each time the power is turned on. Reference numeral 35 denotes a waveform shaping circuit that shapes the secondary side output waveform of the transformer 31 into a rectangular wave and outputs a synchronization pulse P ₁ synchronized with the power supply frequency. Reference numeral 36 divides the output of the waveform shaping circuit 35 to, for example, 0. It is a frequency dividing circuit that generates a clock pulse P _{2 of} 5 Hz. The secondary side output of the current transformer 25 is supplied to an A / D converter 40 via a diode 37, a capacitor 38 and a sampling resistor 39. From the A / D converter 40, a motor is supplied. The detection signal Sa having a digital value indicating the load current of 10 is output. Four
1 is a delay circuit that outputs a delay pulse P ₃ obtained by delaying the clock pulse P ₂ from the frequency dividing circuit 36 by a slight time, 4
Reference numeral 2 denotes a delay circuit which outputs a delayed pulse P ₄ which is obtained by further delaying the delayed pulse P ₃ by some time, and as a result, the frequency is slightly shifted by time by the frequency dividing circuit 36 and the delay circuits 41 and 42. A three-phase signal generation circuit 43 that generates the clock pulse P ₂ and the delay pulses P ₃ and P ₄ is configured. A motor drive circuit 44 turns on the motor drive switch 24 when a "1" signal is input, and turns off the motor drive switch 24 when a "0" signal is input. 45 is a heater drive circuit,
This turns on the heater drive switch 29 when a "1" signal is input, and turns off the heater drive switch 29 when a "0" signal is input. 46, 47
Is a memory circuit, which stores the input digital value to the input terminal M only when a pulse signal is applied to the clock terminal CK, and outputs the stored content from the output terminal Q. 48,4
A subtraction circuit 9 subtracts the input value to the input terminal B from the input value to the input terminal A, and outputs the subtraction results as numerical signals S ₁ and S ₂ from the output terminal C, respectively. Reference numeral 50 is a comparison circuit as a first detection circuit, 51 is a comparison circuit as a second detection circuit, and these compare the input value for the input terminal D and the input value for the input terminal E to determine the clock terminal CK.
When a pulse signal is input to, the output terminal Q outputs a “1” signal when both input values have a relation of D ≧ E, and at the same time, outputs a “0” signal when D <E has a relation. Output. Further, the comparison circuits 50 and 51 forcibly hold the output from the output terminal Q at the "0" signal regardless of the input value when the "1" signal is input to the reset terminal R. 52, 53, 54 are RS flip-flops, 5
Reference numerals 5 and 56 are OR circuits, 57 to 59 are AND circuits, and 60 is an inverter. Reference numerals 61 to 63 denote transfer gates, which are in a conductive state only when the gate terminal receives the "1" signal, and block the passage of the signal when the gate terminal receives the "0" signal. Reference numeral 64 is a counter which is a timer circuit, and 65 is a counter which is an auxiliary timer circuit.
3 is configured to count the clock pulse P ₂ input via 3 and execute a timer operation, and the count value is reset to zero when the input to the reset terminal R rises. Numerical signals S ₃ and S ₄ indicating the contents of the count are output respectively. 66, 67, 6
Reference numeral 8 is a comparison circuit having a function different from that of the comparison circuits 50 and 51. The comparison circuit 8 always compares the input value to the input terminal D with the input value to the input terminal E, and "1" when D ≧ E.
A signal is output, and a "0" signal is output when D <E.

Reference numerals 69 to 73 denote constant storage units, in which constants as described below are stored in advance. That is, as in the present embodiment, when the above-described milling operation is performed by the milling mechanism 14 configured such that the coffee beans in the crushing case 12 are sequentially stored in the extractor 5, the load flowing to the motor 10 is reduced. As shown in FIG. 2, the current is 0.1 after the start of energization.
In the state where the maximum value is exhibited in 0.2 seconds and the steady current is reduced when 1 to 2 seconds have passed, and after that, the coffee beans are crushed in the crushing case 12, As the crushing progresses and the produced coffee beans are sequentially transferred to the extractor 5, the gradual decrease (second
(The period indicated by "I" in the figure), and after that, when all the coffee beans in the crushing case 12 are crushed, it decreases relatively sharply (the period indicated by "II" in FIG. 2), and the generated coffee grounds All of the above are stabilized at a constant current value when blown off from the crushing case 12. Among such phenomena, the phenomenon in which the steady load current of the motor 10 gradually decreases and the phenomenon in which the steady load current decreases relatively sharply thereafter are the phenomena characteristically occurring in the mill mechanism 14 according to the present embodiment. The rate of change of the current value when the value gradually decreases and the time when the value sharply decreases greatly vary depending on the amount of coffee beans stored in the crushing case 12, and the more the amount of coffee beans is, the more steady the value becomes. As the rate of decrease of the load current value increases, the time when the load current value decreases relatively sharply becomes late. Of course, such load current change characteristics of the motor 10 are not limited to the amount of coffee beans, but vary depending on the type of coffee beans, the freshness, the roasted state, and the stored state. Is a constant current value. Therefore, the constant storage unit 69 stores in the constant storage unit 69 a value larger than the decreasing current value ΔIa every 0.5 seconds when the steady load current of the motor 10 gradually decreases, and the steady load current is relatively steep. A decreasing current value ΔIb (ΔIb> ΔI) every 0.5 seconds when decreasing
The current value "Ix" smaller than a) is stored. Further, the constant storage unit 70 stores a current value “Iy” that is smaller than the decreasing current value ΔIa every 0.5 seconds when the steady load current of the motor 10 gradually decreases. Further, the constant storage units 71, 72, 73 store the count values of the counters 64, 65, that is, the numerical values corresponding to the time measured by the counters 64, 65, and the constant storage unit 71 stores the load of the motor 10. A value corresponding to, for example, 2 seconds or more, which is the time required for the current to stabilize to a substantially steady state after the start of energization, is stored, and the other constant storage units 72 and 73 respectively store, for example, 20
The value corresponding to seconds and 1 second is stored.

On the other hand, 74 and 75 are a start switch and a stop switch provided in the coffee maker main body 1, respectively, and when these are turned on, a start pulse P ₅ and a stop pulse P ₆ are output from each. Then, in the present embodiment, the frequency dividing circuit 36 and the delay circuits 41 and 4
2, storage circuits 46, 47, subtraction circuits 48, 49, comparison circuits 50, 51, RS flip-flops 52, 53, A
ND circuit 57, transfer gate 61, constant storage unit 6
A constant current detecting means 76 is configured by 9, 70, and includes a motor drive circuit 44, an OR circuit 56, an AND circuit 58, an inverter 60, a transfer gate 63, a counter 65,
The comparison circuit 68 and the constant storage unit 73 constitute a control means 77.

Next, the operation of the electrical configuration of FIG. 1 will be described with reference to the time chart of FIG. In FIG. 3, the voltage Va across the resistor 39 (indicating the load current of the motor 10), the differentiation circuit 32, the start switch 74,
RS flip-flop 54, stop switch 75,
Comparing circuit 66, RS flip-flops 52, 53, A
The respective outputs of the ND circuit 57, the comparison circuit 68, the AND circuits 58 and 59, and the energization period of the heater 27 are shown in correspondence with the respective signs. When extracting the coffee liquid, the coffee beans are stored in the crushing case 12 and the water is supplied into the water storage tank 2 to set the state as shown in FIG. 4, as described above. Then, after this, at time t in FIG.
_{When the} start switch 74 is turned on at ₁ , the start pulse P ₅ is output, so that the RS flip-flop 54 is set and the "1" signal is output from the output terminal Q thereof. Therefore, the transfer gate 62 becomes conductive, and the counter 64 causes the frequency divider circuit 36 to operate.
To count the clock pulse P ₂ every 0.5 seconds. The counter 64 receives the initialization pulse P ₀ via the OR circuit 55 and is reset when the initialization pulse P ₀ is output from the differentiating circuit 32 (time t ₀ ) when the power is turned on. And at this time RS
The flip-flops 52, 53, 54, the counter 65, and the comparison circuits 50, 51 are also reset at the same time. Counter 6
When 4 is reset, its output, that is, the numerical signal S
_{Since 3} is zero, the inputs of the input terminals D and E of the comparison circuit 66 are D <E (D = 0, E = 2 (constants stored in the constant storage unit 71)). Output "0" signal, and in the comparison circuit 67, the inputs of its input terminals D and E are D <E (D = 0, E = 20).
(Constant stored in the constant storage unit 72)) and becomes “0”.
It will output a signal. Further, even when the counter 65 is reset, its output, that is, the numerical signal S ₄ is zero. Therefore, in the comparison circuit 68, its input terminal D,
Each input of E is D <E (D = 0, E = 1 (constant storage unit 73
The constant stored in the above))) is output and a "0" signal is output. Therefore, the OR circuit 56 outputs the "0" signal, the inverter 60 outputs the "1" signal, and the AND circuit 58 outputs the "1" signal and the "1" from the RS flip-flop 54. Upon receiving the signal, the motor drive circuit 44 is given a "1" signal. Therefore,
The motor drive circuit 24 turns on the motor drive switch 24, and accordingly, the motor 10 is energized to start driving the mill mechanism 14. When the count value of the counter 64 (that is, the time measured by the counter 64) reaches a value corresponding to 2 seconds at time t ₂ when 2 seconds have passed after the start of the mill operation, each input value of the comparison circuit 66 becomes D ≧ E. Since the "1" signal is output from now on, the transfer gate 61 is rendered conductive, and the delay pulse P ₄ from the delay circuit 42 causes the comparison circuit 50, 5 in the constant current detecting means 76.
1 is applied to the clock terminal CK. As a result, the comparison circuits 50 and 51 perform the comparison operation every 0.5 seconds.

In the constant current detecting means 76, the storage circuit 4 that receives the detection signal Sa (digital value corresponding to the load current of the motor 10) from the AD converter 40 at the input terminal M.
6 stores the detection signal Sa each time the delay pulse P ₃ is applied from the delay circuit 41, and the storage circuit 47 which receives the storage content of the storage circuit 46 at the input terminal M is the storage content of the storage circuit 46. Is stored each time the clock pulse P ₂ is output from the frequency dividing circuit 36. At this time, since the phase of the clock pulse P ₂ leads the phase of the delay pulse P ₃ , the change rate of the load current value of the motor 10 can be known by comparing the detection signals stored in the storage circuits 46 and 47. The motor 1
In the state in which 2 seconds have passed after the start of energization of 0, the load current of the motor 4 is already in a state of gradually decreasing to a substantially steady current value as described above. The level becomes higher than the stored contents of the storage circuit 46. Then, the numerical signals S ₁ and S output by the subtraction circuits 48 and 49 for subtracting the stored contents of the storage circuits 46 and 47.
₂ indicates a decrease value of the load current of the motor 10 in a certain time, that is, a decrease rate of the load current value of the motor 10. Then, as described above, one of the comparison circuits 50 and 51 in the state where the comparison operation is started every 0.5 seconds at time t ₂ , one comparison circuit 50 receives the numerical signal S ₁ from the subtraction circuit 48. The stored value “Ix” in the constant storage unit 69 is compared to determine whether the motor 1
The steady load current of 0 gradually decreases (the period indicated by "I" in FIG. 2), that is, the signal "0" is output when S ₁ <Ix, but the load current of the motor 10 is compared. Suddenly decreases (time t ₃ ), S ₁
The relation of ≧ Ix comes to output the standby signal “1” signal, and the RS flip-flop 52 is set by this “1” signal. The other comparison circuit 5
1 is the numerical signal S ₂ from the subtraction circuit 49 and the constant storage unit 7
The stored value “Iy” of 0 is compared, and the steady load current of the motor 10 is gradually reduced and the steady load current is relatively steeply reduced (period shown by “II” in FIG. 2), That is, the signal “0” is output when S ₁ ≧ Iy, but when the load current of the motor 10 becomes relatively steep and then stabilizes at a constant current value (time t ₄ ), S ₁ <"1" which is the end signal due to the relationship of Iy
A signal is output, and R is generated by this "1" signal.
-S flip-flop 53 is set. Therefore, as a result, the AND circuit 57 outputs the detection signal Sd including the "1" signal.

Thus, the detection signal S output from the constant current detection means 76
d is given to the control means 77, and the transfer gate 63 in the control means 77 receives the detection signal Sd at its gate terminal and is rendered conductive. Therefore, the counter 65 displays the time t
_The clock pulse P ₂ is counted from ₄ ,
When the count value (that is, the time measured by the counter 65) reaches the value corresponding to 1 second, time t ₅ is reached, the input value of the comparison circuit 68 becomes D ≧ E, and the comparison circuit 68 outputs a “1” signal. Is output. Then, the output of the inverter 60 is inverted into the “0” signal and the AND circuit 58 outputs the “0” signal. Therefore, the motor drive circuit 44 receiving the “0” signal turns off the motor drive switch 24. As a result, the motor 10 is cut off and the mill operation is automatically terminated. And at the same time, the AND circuit 59
Since the "1" signal is given to both input terminals of
The heater drive circuit 4 which receives the "1" signal from the D circuit 59
5 turns on the heater drive switch 29, and accordingly, the heater 27 is energized to start the drip operation. After the drip operation is completed, the temperature of the heating table 3 rises and the thermostat 26 is turned off (time t ₆ ). Thereafter, the heater 27 is controlled by the thermostat 26.

Since at time _{t 7} after the stop switch 75 when it is turned on, R-S flip-flops 52, 53, 54 and counter 64, 65 is output stop pulse _{P 6} now is reset, in particular In response to the resetting of the RS flip-flop 54, the output of the AND circuit 59 is inverted to the "0" signal and the heater drive circuit 45 turns off the heater drive switch 29, whereby the heat retention operation is stopped. Like

If the constant current detecting means 76 does not operate normally due to noise or the like due to the load current of the motor 10, the counting operation start time t ₁ to 20 of the counter 64 starts.
When seconds (corresponding to the constant stored in the constant storage unit 72) have elapsed, the input values of the comparison circuit 67 have a relationship of D ≧ E, and the comparison circuit 67 outputs the “1” signal.
The output of the inverter 60 is "0" by this "1" signal.
The signal is inverted, so that the mill operation is automatically terminated and the drip operation is started. Therefore, in this case, the constant storage unit 7
2 stores a value that is equal to or longer than the time required to crush all coffee beans in an amount corresponding to the maximum mill capacity and store them in the extractor 5 during the mill operation of the mill mechanism 14.

According to this embodiment described above, when the mill mechanism 14 performs the milling operation, the motor 1 for driving the milling mechanism 14 is performed.
When the load current value of 0 is stabilized at a constant value, in other words, when all the coffee beans in the crushing case 12 are crushed and blown off and the crushing case 12 becomes empty, the detection signal Sd is output. Since the mill operation is automatically terminated based on the detection signal Sd, the mill time is
Regardless of the amount, type, freshness, roasted state, stored state, etc. of coffee beans, the optimum time can always be set, so that coffee beans or coffee grounds remain in the grinding case 12 as in the conventional case. Therefore, there is no fear that the mill operation time becomes excessive and wasteful power is consumed. Moreover, in this case, the milling operation is not immediately terminated in response to the output of the detection signal Sd, but 1 after the output of the detection signal Sd.
Since the milling operation is finished only after the lapse of a second, the coffee powder generated in the crushing case 12 can be surely blown to the extractor 5.
Of course, since the milling operation is automatically performed only by operating the start switch 74, even a person who is completely new to the operation can use it very easily without any skill. Further, as described above, the motor 10
When the detection signal Sd is output when the load current value of 1 is stable at a constant value, the detection signal Sd is always output when the crushing case 12 is empty regardless of the characteristic variation of the motor 10. It can be output.

Although the constant current detecting means 76 in the above embodiment is configured to directly sample the rate of change of the load current value of the motor 10 to determine the output timing of the detection signal Sd, in order to remove the noise component, A configuration may be adopted in which the rate of change of the load current value is sampled a plurality of times within a fixed time, and the output timing of the detection signal is determined based on the average value thereof. In addition, the subtraction circuit 4 in the constant current detection means 76
8, comparison circuit 50, RS flip-flop 52, AN
The D circuit 57 and the constant storage unit 69 may be provided as necessary, and the transfer gate 6 in the control means 77 may be provided.
3, the counter 65, the comparison circuit 68, and the constant storage unit 73 may be provided as necessary. Further, in the present embodiment, the transfer gate 61, the comparison circuit 66, and the constant storage unit 71 are provided in order to suppress the influence of the inrush current when the motor 10 is powered on, but these need not be provided in particular. . In addition, in the above embodiment, the cycle of the clock pulse P ₂ may be advanced in order to perform finer control.

[Effects of the Invention] According to the present invention, as is clear from the above description, in a coffee mill having a mill mechanism in which the coffee powder generated in the crushing case is sequentially stored in the storage case, the mill using the mill mechanism is used. The time can be automatically controlled to be the optimum time according to the amount, type, freshness, roasting state, storage state, etc. of the coffee beans stored in the crushing case. There is no risk that coffee beans or coffee grounds will be left behind and that the motor energization time will be too long, resulting in wasted power consumption, so anyone can use it extremely easily and properly without the need for skill. It has the effect of being able to do so.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a block diagram of an electrical configuration, FIG. 2 is a change characteristic diagram of a load current of a motor, FIG. 3 is a time chart for explaining operation, and FIG. The figure shows a side view of the entire coffee maker with a part broken away.
The figure is an exploded perspective view of a main part of the coffee maker. In the figure, 1 is a coffee maker main body, 5 is an extractor (housing case), 10 is a motor, 12 is a crushing case, 14 is a mill mechanism, 24 is a motor drive switch (switch means),
25 is a current transformer (current detector), 27 is a heater, 29 is a heater drive switch, 44 is a motor drive circuit, 45 is a heater drive circuit, 50 is a comparison circuit (first detection circuit), 51
Is a comparison circuit (second detection circuit), 64 is a counter (timer circuit), 65 is a counter (auxiliary timer circuit), 74 is a start switch (mill operation start switch), 75 is a stop switch, and 76 is a constant current detection. Means, 77 is a control means.

Claims (4)

[Claims] 1. A mill mechanism for crushing coffee beans in a crushing case and sequentially storing coffee powder generated by the crushing in a storing case, a motor for driving the mill mechanism, and a motor for driving the motor. A switch means for controlling the disconnection, a current detector for detecting the load current of the motor, a constant current detecting means for outputting a detection signal when the value detected by the current detector stabilizes at a constant value, and a mill And a control means for turning on the switch means in response to the operation of the operation start switch to start energizing the motor and for turning off the switch means when the detection signal is output thereafter to disconnect the motor. A coffee mill that is equipped with. 2. A first detection circuit for detecting a constant current when the detection value of the current detector gradually decreases from a gradually decreasing state and outputting a standby signal, A second detection circuit for detecting the output of the standby signal when the detected value stabilizes at a constant value and outputting an end signal when the standby signal and the end signal are both output. The coffee mill according to claim 1, wherein the coffee mill is configured to output a detection signal. 3. The constant current detecting means has a timer circuit for starting a timer operation in response to the start of a mill operation, and is configured to hold the operation stopped state until the time measured by the timer circuit exceeds a predetermined time. The coffee mill according to claim 1, which is characterized in that 4. The control means has an auxiliary timer circuit for starting a timer operation in response to the output of the detection signal, and the switch means is turned off only when the time measured by the auxiliary timer circuit reaches a fixed time. The coffee mill according to claim 1, wherein the coffee mill is configured as follows.