JPS61240920A - Coffee mill - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a mill mechanism driven by a motor, particularly a mill mechanism that grinds coffee beans in a grinding case and sequentially transfers coffee powder produced by the grinding to a storage case. The present invention relates to a coffee mill comprising a mill mechanism accommodated therein.

[Technical background of the invention and its problems] Conventionally, in this type of coffee mill, the energization time of the motor for driving the mill mechanism, that is, the milling time, has been controlled by a mechanical or electronic timer. It is configured.

In such a configuration, the time it takes for all the coffee beans in the grinding case to be ground and the time it takes for all the generated coffee powder to be stored in the storage case are the same as the mother 1 of the coffee beans to be milled. This varies greatly depending on the type, freshness, roasting status, storage status, etc., and therefore the user must consider the set time each time the timer is used to set the mill time. However, it is actually extremely difficult to set the timer optimally, and as a result, coffee beans or coffee powder may remain in the grinding case due to insufficient operating time of the motor, or vice versa. There were problems such as excessive time and unnecessary power consumption.

[Object of the Invention] The present invention has been made in view of the above circumstances, and its object is to shorten the milling time by a mill mechanism that sequentially stores coffee powder produced in a grinding case into a storage case. The amount of coffee beans or coffee powder stored in the grinding case can be automatically controlled to be the optimal time according to the nine types of coffee beans, freshness, roasting status, storage status, etc. This eliminates the risk of the motor being left behind or the motor being energized for too long, resulting in wasted power consumption.
Therefore, anyone can use it extremely easily and properly without requiring any skill, and furthermore, the automatic control of the mill time as described above can always be performed accurately regardless of the characteristics of the motor, etc. A coffee grinder is provided.

[Summary of the Invention] In order to achieve the above object, the present invention includes a mill mechanism that grinds coffee beans in a grinding case and sequentially stores coffee powder produced by the grinding in a storage case. In the coffee mill, a switch means for controlling energization/disconnection of the motor for driving the mill mechanism, a current detector for detecting the load current of the motor, and is operated when no coffee beans are housed in the mill mechanism. auxiliary drive means for driving the motor by turning on the switch means in response to turning on of an auxiliary switch provided as shown in FIG.
Storage means for storing the load current of the motor driven by the auxiliary drive means based on the output of the current detector, and turning on the switch means in response to operation of a mill operation start switch to start energizing the motor. and a control means for turning off the switch means and cutting off the motor based on the fact that the current detected value by the current detector has a predetermined relationship with the stored current value of the storage means. As a result, when all the coffee beans stored in the grinding case are ground and stored in the storage case, the power supply to the motor is automatically stopped.

Embodiment of the Invention] Hereinafter, an embodiment in which the present invention is applied to a coffee maker will be described.

Part 4 shows the overall configuration and main parts of the coffee maker.
In the figures and FIG. 5, 1 is the main body of the coffee maker;
A cartridge type water storage tank 2 is provided on the left side in the figure, and a heating table 3 is provided on the lower right side. Inside this heating table 3 is a heater (shown with reference numeral 27 in FIG. 1).
A well-known hot water generation mechanism consisting of a heating tube (not shown) and a heating tube (not shown) is provided, and the water in the water storage tank 2 is supplied into the heating tube and turned into hot water. 4 is a bottle placed on a heating table 3; 5 is a cup-shaped extractor serving as a storage case placed above the bottle 4; (see FIG. 5) is removably attached to the coffee maker main body 1 by inserting it into a protrusion 7 (see FIG. 5) formed in an upright shape. Such extractor 5
An extraction port 8 is formed at the bottom of the container, 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 a9 comes into contact with the bottle lid 4a placed on the bottle 4 and is in an open state. Reference numeral 1o denotes a vertical shaft motor disposed on the coffee maker main body 1 on the left side of the extractor 5 in the drawing, and a case mounting portion 11 is formed in the upper part of the motor 10. Reference numeral 12 denotes a crushing case that is detachably attached to the case attachment part 11, and a motor 10 is installed at the inner bottom of this case.
A grinding body 13 is provided which is rotationally driven by a grinding body 13, and these constitute a mill mechanism 14.

A powder filter part 12a (see FIG. 5) is provided on the right side of the grinding case 12 by forming a large number of fine holes, and this powder filter part 12a faces the upper opening of the extractor 5. There is. Reference numeral 15 denotes a hood section for guiding the coffee powder from the powder filter section 12a into the extractor 5. One end of this hood surrounds the top and both sides of the powder filter section 12a, and the other end surrounds the top surface of the extractor 5. It extends near the center of the opening. The hood part 15 is formed into a substantially arc shape that moves away from the crushing case 12 toward the bottom, and a cylindrical hot water pan 16 is integrally formed on the top surface. A pouring hole 17 is formed. Reference numeral 18 denotes a lid portion that covers the outer part of the hood portion 15 of the upper opening of the extractor 5, and a cylindrical portion 19 that is inserted into the inner circumference of the upper end of the extractor 5 is integrally formed on the lower surface of this lid portion. There is. Then, the upper end of the paper filter 20 housed in the extractor 5
and the cylindrical portion 19 and are held therebetween. The hood portion 15 and lid portion 18 configured as described above are integrally provided in the crushing case 12. Furthermore, 2
1 is a hot water supply spout body rotatably provided above the hot water pan 16;
Hot water generated by the heating pipe of the hot water generating mechanism described above is discharged from the hot water supply spout 21 into the hot water receiver 16. Reference numeral 22 denotes a cap detachably placed on the upper surface of the crushing case.

In order to extract coffee liquid using a coffee maker with such a configuration, first, coffee beans for the number of people are stored in the grinding case 12, and a predetermined amount of water is stored in the water storage tank 2. Set to the state shown. Then, when the motor 10 is energized, the mill mechanism 14 is driven and the grinding body 13 starts grinding the coffee beans, that is, the milling operation. As a result, the generated coffee powder is transferred to the powder filter section 1.
When the particle size becomes smaller than the fine pores 2a, the particles fly out of the powder filter section 12a due to centrifugal force. The coffee powder that flies out falls onto the paper filter 20 in the extractor 5 while being guided by the arc-shaped hood part 15.

In this case, the hood part 15, which functions to introduce the coffee powder produced in the grinding case 12 into the extractor 5, has an extremely simple structure and connects the grinding case 12 and the extractor 5 at substantially the shortest distance. Therefore, the amount of coffee powder that adheres to the hood portion 15 and is not collected into the extractor 5 is reduced, and the recovery rate of coffee powder is increased. In addition, since the outer part of the hood part 15 of the upper surface opening of the extractor 5 is covered with the lid part 18, the wind generated in the crushing case 12 due to the rotation of the crushing body 13 flows into the extractor 5. Even if the coffee is blown, the lid 18 prevents the coffee powder inside the extractor 5 from being blown out of the extractor 5 by this wind. After pulverizing all the coffee beans in this way, when the heater 27 (see FIG. 3) of the hot water generation mechanism is energized, the water in the water storage tank 2 is sequentially turned into hot water, and the water is heated from the hot water supply spout 21 to the hot water receiver 16. The coffee powder is discharged from the pouring hole 17 into the hood part 15 and dripped onto the coffee powder on the paper filter 20. The dripped hot water penetrates into the coffee powder to extract the coffee extract from the coffee powder, is filtered by the paper filter 20, and is dripped from the extraction port 8 into the bottle 4 as a coffee liquid and stored. Then, the drip operation is performed.

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

That is, 32 is a capacitor 33. This is a differentiator circuit consisting of a resistor 34, which outputs an initializing pulse Pa every time the power is turned on. 35 is a waveform shaping circuit that shapes the secondary side output waveform of the transformer 31 into a rectangular wave and outputs a synchronization pulse P1 synchronized with the power supply frequency; 36 is a waveform shaping circuit that divides the output of this waveform shaping circuit 35 to generate, for example, a 1H2 clock. This is a frequency dividing circuit that generates pulse P2. The secondary output of the current transformer 25 is connected to a diode, a diode 37. Capacitor 38. Sampling resistor 39
A digital value detection signal Sa indicating the load current of the motor 10 is supplied from the current detection circuit 41 to a current detection circuit 41 consisting of an A-D converter 40 and an A-D converter 40.
is output. 42 is the motor drive circuit, which is "1"
When a signal is input, the motor drive switch 24 is turned on, and when a "0" signal is input, the motor drive switch 24 is turned off. A heater drive circuit 43 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. 44.4
Reference numerals 5 and 46 indicate a start switch, a stop switch, and a check switch, which is an auxiliary switch, which are provided in the coffee maker main body 1, respectively, and when these are turned on, a start pulse P3 is generated from each of them. ．． A stop pulse P4 and a check pulse P5 are output. 47, 48.49 are R-S flip 70 tubes, 50-56 are OR circuits, 57-59 are AN
In the D circuit, 60 is an inverter. Reference numerals 61 to 65 designate transfer gates which are conductive only when receiving a "1" signal at their gate terminals, and block passage of signals when receiving an rOJ signal at their gate terminals. 66-68
The three are circuits, and these input signals range from "0" to "1".
Trigger pulse P6 is output when each rises.

69 is a delay circuit, which delays the input signal by some time (
For example, the output is delayed (about 0.1 seconds). 70.71
．． 72 is a counter, which counts the clock pulses P2 inputted through the transfer gates 51, 62, and 63 corresponding to each clock terminal CK, and also counts when the input to the reset terminal R rises. It is configured so that the value is reset to zero, and a numerical signal sm indicating the contents of each count is output from the output terminal Q.
, sn, and so, respectively. Comparing circuits 73 to 77 compare the input value to input terminal A and the input value to input terminal B, and output a "1" signal when A≧B.
The rOJ signal is output when A<8. Reference numeral 78 denotes a storage circuit serving as a storage means, which stores the input digital value for the input terminal M (in this case, the detection signal Sa from the current detection circuit 41) only when the trigger pulse P6 is applied below the trigger terminal, and also stores the stored contents. It outputs a numerical signal Sx corresponding to the output terminal Q from the output terminal Q, and holds the stored contents until the next trigger pulse P6 is applied. Reference numeral 79 denotes an adder circuit that adds the respective input values to the input terminals X and Y, and outputs the addition result from the output terminal Z as a numerical signal Sz.

Numerals 80 to 85 are constant storage sections, in which constants described below are stored. That is, when the above-described milling operation is performed by the mill mechanism 14 configured to sequentially accommodate the coffee beans in the grinding case 12 into the extractor 5 after being ground, as in this embodiment, the load flowing to the motor 10 is As shown in FIG. 2, the current once reaches its maximum value 0.1 to 0.2 seconds after the start of energization, stabilizes to a steady state after 1 to 2 seconds, and even after this, the crushing case 12
While the coffee beans are being ground in the extractor 5, as the grinding progresses and the produced coffee beans are sequentially transferred to the extractor 5, the rate gradually decreases as shown in FIG.
(period indicated by J), after which the coffee beans in the grinding case 12 are all ground, and after that, it decreases relatively steeply (period shown by rlIJ in FIG. 2), and all of the generated coffee powder is removed from the grinding case 12. When it is blown away, in other words, when the motor 10 is in a no-load state (the no-load state here refers to a state in which the crushing case 12 is empty), the current value becomes stable at a constant value.

Among these phenomena, the phenomenon in which the load current once increases to the maximum value after the motor 10 starts energizing is caused by an inrush current, so it also occurs in general coffee mills, but the steady load of the motor 10 The phenomenon in which the current gradually decreases and the phenomenon in which the current decreases relatively steeply and then stabilizes at a constant value are phenomena that characteristically occur in the mill mechanism 14 according to this embodiment. The time when the load current of the motor 10 decreases and stabilizes at a constant value (mill operation end time) varies greatly depending on the number of coffee beans stored in the grinding case 12. The larger the amount, the later it takes for the load current to stabilize at a constant value. Of course, the change characteristics of the load current of the motor 10 are not limited to the amount of coffee beans, but also depend on the type of coffee beans, freshness, roasting state,
Although it varies depending on the state of storage, the current value eventually settles on a constant value in any case. However,
The constant storage units so and si store a constant corresponding to, for example, 2 (seconds) which is longer than WR until the load current of the motor 10 stabilizes to a steady state after the start of energization. Further, the constant storage unit 82 stores a constant corresponding to, for example, 20 (seconds), and the constant storage unit 83 stores a compensation value, for example, 2 (seconds).
seconds) is stored in the constant storage section 84.
A constant corresponding to (ampere) is stored in the constant storage section 85, and a correction current value, for example, 0.1 (ampere) is stored in the constant storage section 85.
Constants corresponding to are stored respectively.

In this embodiment, the frequency dividing circuit 36. Motor drive circuit 42. R-8 flip-flop47. OR circuit 50.5
1.56. Transfer gate 61, trigger circuit 66
．． 67, delay circuit 69. Counter 70. Comparison circuit 73.
The constant storage section 80 constitutes an auxiliary drive means 86,
Frequency dividing circuit 36° motor drive circuit 42. R-S flip-flop 48.49. OR circuits 52-56. AND circuit 5
7°58, inverter 60. Transfer gate 62~
64. Trigger circuit 68. Counters 71, 72° comparison circuits 74-77, addition circuit 79. The constant storage units 81 to 85 constitute a control means 87.

Next, the operation of the electrical configuration shown in FIG. 1 will be explained with reference to the timing chart shown in FIG. 3. Note that FIG. 3 shows the output waveforms of each part in FIG. 1, and the voltage Va across the resistor 39 (indicating the load current of the motor 10)
, differentiation circuit 32. Check switch 46. R-S flip-flop 47, start switch 44. R-S flip 70 knob 48. Stop switch 45. Comparison circuit 74
゜77.76, OR circuit 56. Each output of the AND circuit 59 and the energization period of the heater 27 are shown corresponding to the respective symbols. Now, time i to extract the coffee liquid.
When the power is turned on at o (see Figure 3), the differentiator circuit 3
2 outputs an initializing pulse PO, and this initializing pulse Pa resets the R-S flip-flops 47 to 49 and initializes the counts of the counters 71 and 72. Thereafter, when the check switch 46 is turned on at time 11 before coffee beans are stored in the grinding case 12, a check pulse Ps is output, and the R-8 flip-flop 47 is set in response to the output. A "1" signal is output from terminal Q. Then, the motor drive circuit 42 that receives this "1" signal via the OR circuit 56 turns on the motor drive switch 24, so that the motor 10 is energized and driven.
In response to this, the mill mechanism 14 starts driving in a no-load state. Furthermore, at this time t1, the trigger circuit 66 that receives the "1" signal from the output terminal Q of the R-S flip-flop 47 outputs the trigger pulse P6, so that the counter 70 is initialized and at the same time The transfer gate 61 which receives the "1" signal at its gate terminal becomes conductive, and the counter 70 starts counting the clock pulses P2 every second from the frequency dividing circuit 36 from the initial state.

Therefore, the numerical signal Sm output by the counter 70 is at time t
It corresponds to the elapsed time from 1.

At time t2, which is 2 seconds after the time tl at which the counter 70 starts counting, the comparator circuit 73 receives its input terminal A.

Each input of B becomes A=B (A=2 (corresponding to numerical signal Sm from counter 70)>, B=2 (constant stored in constant storage section 80)) and outputs a "1" signal. Then, the trigger circuit 67 that receives this "1" signal starts outputting the trigger pulse P6, and the memory circuit 78 that receives this trigger pulse P6 below the trigger terminal outputs the trigger pulse P6 at the time t.
2 (corresponding to the load current value in a steady state when the motor 1o is driven with no load) is stored. When the trigger pulse P6 is output from the trigger circuit 67 in this manner, the R-S flip 70 knob 49 is set by the trigger pulse P6, and a "1" signal is output from the set output terminal Q and the reset output terminal Q. to “0”
'' signal is output, the transfer gate 65 corresponding to the memory circuit 78 is in a conductive state, the transfer gate 64 corresponding to the constant memory section 84 is in a cut-off state, and the numerical signal SX from the memory circuit 78 is added. circuit 7
9 will be given. At the same time, the counter 70 receives the trigger pulse P6 at the reset terminal R.
is initialized, and the R-S flip 70 knob 47 that receives the trigger pulse P6 via the delay circuit 67 is reset at time 1-=. Therefore, in response to the reset of the R-S flip-flop 47, the supply of the "1" signal to the motor drive circuit 42 is stopped, so the motor drive switch 24 is turned off, and the motor 1
0 is stopped. In short, the memory circuit 78 stores the detected current value of the current transformer 25 when the motor 10 is driven in a no-load state and stabilizes in a steady state. Drives the motor 10 in response to turning on the switch 46, and
As described above, when the load current of the motor 10 in the no-load driving state is stored in the memory circuit 78, the motor 10 is automatically cut off and stopped.

After the drive of the motor 10 is stopped in response to the turning on of the check switch 46, the coffee beans are stored in the grinding case 12 and water is supplied to the water storage tank 2, as described above. Set as shown in Figure 4. Then, at time t3 in FIG. 3, the start switch 4
4, a start pulse P3 is output, so that the R-8 flip-flop 48 is set and a "1" signal is output from its output terminal Q. Therefore, the transfer gate 62 becomes conductive and the counter 7
1 counts clock pulses P2 every second from the frequency dividing circuit 36, and therefore, the numerical signal Sn output from the counter 71 corresponds to the elapsed time from time t3. The counters 71 and 72 are initialized when the power is turned on as described above, but the trigger circuit 68 is also initialized when the "1" signal is output from the R-S flip-flop 48 as described above. It is initialized in response to a trigger pulse P6 from , and thereby, when continuously performing coffee extraction operations, there is no need to turn on the power again each time. Now, when the counter 72 is reset, its output, that is, the numerical signal So, is zero, so in the comparator circuit 76, each input of its input terminals A and B is A<B (A
=0 (corresponding to the numerical signal SO from the counter 72), B-
2 (constant stored in the constant storage unit 83)) and becomes “0.
” signal will be output. Further, at this time, since the output of the counter 71, that is, the numerical signal Sn, which is also in the reset state, is also zero, the input terminals A and B of the comparator circuit 75 also have the input terminals A<B (A-0(numerical signal S
n), B=20 (constant stored in the constant storage section 82)), and a "0" signal is output. Therefore, the OR circuit 55 outputs a "0" signal and the inverter 60 outputs a "1" signal, and the AND circuit 58 outputs this "1" signal and the "1" signal from the R-S flip 70 tube 48. ” signal, the motor drive circuit 42 receives the “
1] Becomes to give a signal. Therefore, the motor drive switch 24 is turned on by the motor drive circuit 42, and in response, the motor 10 is energized to start driving the mill mechanism 14. Time t when 2 seconds have passed after the start of this mill operation
4 and the count value of the counter 71 reaches a value equivalent to 2 seconds, each input value of the comparator circuit 74 becomes A≧8 and a "1" signal is output from now on, so this "1" signal is received. AND circuit 57 now allows the signal from comparison circuit 77 to pass.

That is, the AND circuit 57 allows the signal from the comparator circuit 77 to pass only when the load current of the motor 10 stabilizes to a steady state after starting the mill operation in response to the drive of the motor 10.

When the milling operation is performed in this manner, the load current of the motor 10 and the detection signal Sa of the digital value corresponding to the load current gradually decrease as the milling operation progresses. At this time, as described above, the transfer gate 65 is in a conductive state, and the addition circuit 79 receives a numerical signal Sx from the storage circuit 78 (corresponding to the load current value of the motor 10 in the no-load driving state).
A constant (corresponding to 0 or 1 ampere) stored in the constant storage section 85 is added to the constant, and the addition result is output as a numerical signal Sz. Therefore, the load current value of the motor 10 gradually decreases as described above, and the detection signal Sa changes to the numerical signal Sz.
(time t6), the comparator circuit 77
input terminal A.

Each input of B becomes A2B, and the comparator circuit 77 outputs "
1” signal is output. Then, that "1" signal becomes AN
Since the signal passes through the D circuit 57 and is applied to the gate terminal of the transfer gate 63, the counter 72 starts counting the clock pulse P2. At time 1G, when the count value of the counter 72 reaches a value equivalent to 2 seconds, the input value of the comparison circuit 76 becomes A≧8, and the comparison circuit 76 outputs a "1" signal. Then, a "1" signal is output from the OR circuit 55, and the output of the inverter 60 is inverted to a "0" signal, so that the AND circuit 58
starts to output the rOJ signal, so the motor drive circuit 42 that receives this "0" signal switches the motor drive switch 2.
4 is turned off, thereby cutting off the power to the motor 10 and automatically ending the mill operation. And at the same time, AN
R-S flip 70 tube 48 to both input terminals of D circuit 59
Since each "1" signal is given from the AND circuit 55, the heater drive circuit 43 that receives the "1" signal from the AND circuit 59 turns on the heater drive switch 29, and accordingly energizes the heater 27. drip operation is started. After the drip operation is completed, the temperature of the heating table 3 rises and the thermostat 26 turns off (time it), and from then on the heater 27 turns off the thermostat 2.
A heat-retaining operation is performed, which is controlled by 6.

Then, when the stop switch 45 is turned on after this time, the stop pulse P4 is outputted, the R-S flip-flop 48 is reset, and the counters 71 and 72 are initialized. Especially R
- In response to the reset of the S flip-flop 48, the output of the AND circuit 59 is inverted to a "0" signal, and the heater drive circuit 4
3 turns off the heater drive switch 29,
As a result, the heat-retaining operation is stopped.

Incidentally, when the start switch 44 is turned on without turning on the check switch 46 when the mill operation starts for the first time after the power is turned on, the R-S flip-flop 49 is left in the reset state and the transfer gate 64 is turned on. exhibits a conductive state and transfer gate 6
5 exhibits a cut-off state, the constant (corresponding to 1 ampere) stored in the constant storage section 84 is applied to the input terminal X of the addition circuit 79 as a substitute value for the stored current value of the storage circuit 78. Therefore, even if you forget to turn on the check switch 46 before storing coffee beans in the grinding case 12, the machine will not become unusable.

In addition, in the event that the control means 87 does not operate normally due to noise caused by the load current of the motor 10, etc., the control means 87 may be operated for 20 seconds (corresponding to the constant stored in the constant storage section 82) from the counting operation start time t3 of the counter 71. ) has passed,
Since each input value of the comparison circuit 75 has an A2B relationship and a "1" signal is output from the comparison circuit 75, this "1" signal is output from the comparison circuit 75.
'' signal inverts the output of the inverter 60 to a ``0'' signal, thereby automatically ending the mill operation and transitioning to the drip operation. Therefore, in this case, the constant storage section 82 has
When the milling mechanism 14 operates, a value that is longer than the time required to grind all the coffee beans corresponding to the maximum milling capacity and store them in the extractor 5 is stored.

According to the present embodiment described above, when the milling mechanism 14 performs the milling operation, the motor 10 is driven in a no-load state before the coffee beans are stored in the grinding case 12.
The load current value of the motor 10 at that time is stored in the memory circuit 78, and during the mill operation, the load current value of the motor 10 has a predetermined relationship with the stored current value (actually, the stored current value has a corrected current value (0). . Since the milling time is configured to be terminated, the milling time can always be set to the optimum time regardless of the amount of coffee beans, the type of coffee beans, the freshness, the roasting state, the storage state, etc. This eliminates the risk of coffee beans or coffee powder being left behind, or the mill operating time becoming excessive, resulting in wasted power consumption, as in the prior art. Moreover, in this case, the mill operation is not ended immediately when the load current value of the motor 10 during mill operation reaches a predetermined relationship with the stored current value of the memory circuit 78, but after the mill operation reaches the predetermined relationship. Since the milling operation is ended only when two seconds have elapsed, the coffee powder produced in the grinding case 12 can be reliably blown to the extractor 5. Of course, since the milling operation described above is automatically performed by simply operating the start switch 44, even a first-time user can use it extremely easily without any skill. Furthermore, as described above, when the mill operation is configured to be able to be terminated when the load current value of the motor 10 during the mill operation reaches a predetermined relationship with the load current value during the no-load drive state stored in advance. , motor 10
Regardless of variations in characteristics, the mill operation can always be accurately terminated when the interior of the crushing case 12 becomes empty.

In the above embodiment, the addition circuit 79 and the constant storage section 85 are used as a countermeasure in case the load current value of the motor 10 during mill operation does not fall to the stored current value of the storage circuit 78 due to fluctuations in the power supply voltage. This is provided to stabilize the operation, but this may be provided as necessary, or instead of the adder circuit 79, a multiplier that multiplies the stored current value of the memory circuit 78 by a predetermined coefficient. A configuration in which a circuit is provided may also be used. Furthermore, as described above, the OR circuits 54, 55, . transfer gate 6
3. Counter 72. The comparison circuit 76 and the constant storage section 83 may be provided as necessary. Furthermore, in this embodiment, transfer gates 61, 62 . comparison circuit 73,
74, constant storage sections 80, 81, etc. were provided, but
There is no particular need to provide these.

In addition, in the above embodiment, the memory contents of the memory circuit 78 are held until the check switch 46 is turned on next time, in order to facilitate repeated mill operations. It is not necessary to hold the contents as described above, and the auxiliary drive means 8
7 has a configuration in which the motor 10 is automatically cut off and stopped when the memory circuit 78 stores the load current value of the motor 10, but such a function may also be provided as necessary. . In the above embodiment, the period of the clock pulse P2 may be accelerated in order to perform more fine-grained control, or the constants stored in each of the constant storage sections 80 to 85 may be changed as appropriate. Of course.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with various modifications without departing from the gist of the invention, for example, it may be applied to a single coffee mill. It is something.

[Effects of the Invention] According to the present invention, as is clear from the above description, in a coffee mill equipped with a mill mechanism in which coffee powder produced in a grinding case is sequentially stored in a storage case, time and the amount of coffee beans stored in its grinding case.

It can automatically control the time to be optimal according to the type, freshness, roasting state, storage state, etc., and prevents coffee beans or coffee powder from remaining in the grinding case.
It eliminates the risk of unnecessary power consumption due to excessive energization time of the motor, and anyone can use it extremely easily and properly without requiring any skill. This has the excellent effect of always being able to perform accurately regardless of the characteristics of the motor.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a block diagram of the electrical configuration, Fig. 2 is a change characteristic diagram of the motor load current, Fig. 3 is a time chart for explaining the operation, and Fig. 4 is a block diagram of the electrical configuration. The figure is a partially cutaway side view of the entire coffee maker.
The figure shows an exploded view of the main parts of the same coffee maker. In the figure, 1 is the main body of the coffee maker, 5 is the extractor (accommodation case), 10 is the motor, 12 is the grinding case, 14 is the mill mechanism, 24 is the motor drive switch (switch means),
25 is a current transformer (current detector), 27 is a heater, 29 is a heater drive switch, 41 is a current detection circuit, 42 is a motor drive circuit, 43 is a heater drive circuit, 44 is a start switch (switch for starting mill operation) , 45 is a stop switch, 46 is a check switch (auxiliary switch) 70.
71 and 72 are counters, 78 are memory circuits (memory means),
Reference numeral 86 indicates auxiliary drive means, and reference numeral 87 indicates control means. Applicant Toshiba Corporation Figure 2 Time? , 3 Figure Va Figure 4

Claims (1)

[Claims] 1. A mill mechanism that grinds coffee beans in a grinding case and sequentially stores coffee powder produced by the grinding in a storage case, a motor for driving this mill mechanism, and a motor for driving this mill mechanism. A switch means for controlling power on/off of the motor, a current detector for detecting a load current of the motor, and an auxiliary switch provided to be operated when coffee beans are not stored in the mill mechanism. auxiliary drive means for turning on the switch means to drive the motor in response to turning on of the switch means; and storage means for storing a current value detected by the current detector when the motor is driven by the auxiliary drive means; In response to the operation of the mill operation start switch, the switch means is turned on to start energizing the motor, and after this, the current value detected by the current detector has a predetermined relationship with the current value stored in the storage means. and control means for turning off the switch means and cutting off the power to the motor based on the coffee mill. 2. A patent claim characterized in that the control means is configured to turn off the switch means when the current value detected by the current detector becomes larger than the stored current value of the storage means by a predetermined corrected current value. The coffee mill according to item 1. 3. The control means has a counter that starts counting operation from the time when the current value detected by the current detector has a predetermined relationship with the stored current value of the storage means, and the count value of this counter is set in advance. The coffee mill according to claim 1, characterized in that the switch means is configured to turn off when the compensation value is reached. 4. The storage means is configured to once store the detected current value and retain the stored contents until the auxiliary switch is turned on next time. coffee mill. 5. The auxiliary drive means is configured to stop the motor from being de-energized when the storage means stores the current value detected by the current detector after driving the motor. The coffee mill according to item 1.