JPS6345214B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a coffee mill that uses cutters rotated by a motor to grind coffee beans stored in a case.

Conventionally, this type of coffee mill has one that grinds coffee beans by energizing a motor for a set time, for example, on a clockwork timer. If the cutter is rotated without the cutter attached, the coffee beans will scatter outside the case, so a lid switch is provided to prevent the cutter from rotating by cutting off the electrical current to the motor when the lid is opened. are doing. However, in such conventional coffee mills, the timer operation continues regardless of the state of the lid switch, so the timer operation is not started (in other words, the operation to start the mill operation is not performed). ) If you realize that you forgot to put the lid on and put it back on properly, the motor's energization time, that is, the milling time, will be shorter than the time you originally set, and there will be a problem that you will not be able to grind enough coffee beans. be. In order to deal with such a problem, it is necessary to reset the mill time using a timer when it is noticed that the lid has been forgotten to be attached, which makes the operation cumbersome.

The present invention has been made in view of the above circumstances, and its purpose is to prevent the start of the mill operation when the lid is not installed in the normal position, and to
Even if someone forgets to put on the lid, the coffee beans can be reliably milled for a preset period of time, and there is no risk of running out of mills, and there is no risk of complicated operations. A coffee grinder is provided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a coffee maker having both a hot water supply (drip) mechanism and a mill mechanism, which is the coffee mill referred to in the present invention, will be described below with reference to the drawings.

1 is a lid switch, which is configured to be turned on only when the lid of the case (none of which is shown), which is used for both grinding coffee beans and extracting coffee liquid, is properly installed in a predetermined position. , the lid switch 1, the heater 2, the bimetal switch 3, and the output switch 4a of the heater drive circuit 4, which will be described later, are connected in series in this order to connect both output terminals 5 of the AC power source 5.
a and 5b, and these series circuits constitute a heater circuit A. And heater 2,
A series circuit of a mill motor 6 and an output switch 7a of a motor drive circuit 7 to be described later is connected in parallel with the series circuit of the bimetal switch 3 and output switch 4a. In this case, the motor 6 is attached to a mill mechanism (not shown), and the mill mechanism has a cutter rotated by the motor 6 in the case, and the coffee beans stored in the case are rotated by the rotation of the cutter. to produce coffee powder.
Further, the heater 2 is attached to a hot water supply mechanism (not shown), and the hot water supply mechanism converts water supplied from a water storage tank to the heater into hot water using the heater 2, and lowers the boiling pressure of the hot water thus generated. The coffee liquid is extracted by supplying the coffee powder into the case containing the coffee powder. Furthermore, the bimetallic switch 3 is of a normally closed type that is turned off when the heater reaches a predetermined temperature. On the other hand, 8 is a DC power supply circuit for rectifying the output of the AC power supply 5 and providing it as a power source for a control circuit 9, which will be described later. Only 8a is shown. Reference numeral 10 denotes a detection circuit for determining the state of the heater circuit A, such as the on/off state of the lid switch 1, which will be described below. That is, heater 2 and bimetal switch 3 in heater circuit A
The common connection point constitutes a signal take-out point 11, and this signal take-out point 11 is connected to the base of a PNP type transistor 13 in the detection circuit 10 via a resistor 12.

The emitter of the transistor 13 is connected to the output terminal 5b of the AC power supply 5, the collector of the transistor 13 is connected to the low potential side output line 8a of the DC power supply circuit 8 via the resistor 14, and the base of the transistor 13 is connected to the output terminal 5b of the AC power supply 5.・Resistance 1 between emitters
5 and a diode 16 are connected in parallel. Then, the collector of the transistor 13 forming the output end of the detection circuit 10 is connected to the line _L1 .

Now, the configuration of the control circuit 9 will be described below. In this case, most of the functions of the control circuit 9 can be obtained by a program of a microcomputer, but here, for convenience of explanation, a combination of block circuits will be described. It is shown with. That is,
A frequency divider 17 divides the frequency of the output of the AC power supply 5, and outputs a counting pulse Pc at a period of, for example, 1 Hz. Reference numeral 18 denotes a set switch that is turned on only in the manual operation state, and a high level signal is applied to one input terminal of the AND circuit 19 only when this switch is turned on. The other input terminal of the AND circuit 19 is connected to receive the counting pulse Pc, and therefore, the AND circuit 19 passes the counting pulse Pc only during the ON period of the set switch 18. For example, 20 is a hexadecimal up counter, which is the clock input terminal from the AND circuit 19.
It adds and counts the pulses input to CK and outputs the counted contents as a digital signal Sn. Reference numeral 21 denotes a 3-digit digital display, for example, which is a mill time display and also serves as a warning display consisting of a 7-segment light emitting diode or the like;
The numerical value (maximum 2 digits) corresponding to the digital signal Sn when received through the transfer gate 22
Display. In addition, the above transfer gate 22
has a configuration that exhibits low impedance and allows the signal to pass only when a high level signal is input to its control terminal 22a, and other transfer gates described below have a similar configuration. 23
is a storage section that stores a display information signal Sd of a predetermined mode, and the information signal Sd is input to the digital display 21 when the transfer gate 24 is in a conductive state. When the information signal Sd is input to the digital display 21, the digital display 21 displays, for example, "L1d" as shown in FIG. On the other hand, 25 is a start switch that is turned on only in the manual operation state, and when this is turned on, a high level signal is given to one of the input terminals of the 3-input type AND circuit 26. Similarly, a stop switch 27 is a reset switch that is turned on only in the manual operation state, and when it is turned on, a high level signal is output to line _L2 . 2
8, the set input terminal S is connected to the AND circuit 26.
The first memory circuit R- is connected to the output terminal of the line L2 and the reset input terminal R is connected to the line _L2 .
The output from the set output terminal Q of the S flip-flop is passed through a delay circuit 29 to a judgment circuit.
It is applied to one input terminal of an AND circuit 30, and also directly applied to one input terminal of an AND circuit 31, which is a gate circuit, and the other power terminal of the AND circuit 31 is connected to the line _L1.
It is connected to. At this time, the delay circuit 29 is
The delay time is set to about 20ms, for example. The delay circuit 29 is located downstream of the delay circuit 29.
The output terminal of the AND circuit 30 is connected to the control terminal 22a of the transfer gate 22 via an inverter 32, and is also directly connected to the control terminal 24a of the transfer gate 24. is AND
The transfer gate 24 is conductive when the circuit 30 outputs a low level signal, and the transfer gate 24 is conductive when the AND circuit 30 outputs a high level signal. Reference numeral 33 denotes an R-S flip-flop, which is a second storage circuit, whose set input terminal S is connected to the output terminal of the AND circuit 31, and whose reset input terminal R is connected to the line _L2 . is applied to the other input terminal of the AND circuit 30 via the inverter 34, and is applied directly to the monostable multivibrator 35 which outputs a high level signal for a short time when receiving a rising signal, and is also applied to the delay circuit 36. The signal is also applied to one input terminal of the AND circuit 37 via the . 3
8 is a down counter which has a preset function and a clear function and constitutes a mill time control circuit B together with the up counter 20, digital display 21, etc., and when a digital signal is input to its data input terminal D, In addition to presetting a numerical value corresponding to the input digital signal, the preset value is subtracted from the preset value each time a pulse is input to the clock input terminal CK, and the count is subtracted from the preset value when a high level signal is input to the clear terminal CL. This configuration clears the numerical value to "0". Furthermore, this down counter 38 is configured to output a high level signal only during a period when its count value is other than "0", and operate the motor drive circuit 7 with this high level signal, so that the motor drive circuit 7 is operated. When the circuit 7 is operated in this way, its output switch 7a
Turn on. Further, the data input terminal D of the down counter 38 is connected to the output terminal P of the up counter 20 via the transfer gate 39, the clock input terminal CK is connected to the output terminal of the AND circuit 40, and the clear input terminal CL is connected to the output terminal P of the up counter 20. Connected to the line _L2 . One input terminal of the AND circuit 40 is connected to receive the counting pulse Pc, and the other input terminal is connected to the output terminal P of the down counter 38. In addition, the control terminal 3 of the transfer gate 39
9a is connected to receive the output from the monostable multivibrator 35. Further, the output terminal P of the down counter 38 is branched into two after passing through an inverter 41, and is branched into two, and the output terminal P of the down counter 38 is branched into two branches.
7, and is connected to each input terminal of AND circuit 2.
The remaining input terminals of 6 are connected via the inverter 42.
It is connected to the output terminal of the AND circuit 37. Further, the output terminal of the AND circuit 37 is connected to one input terminal of the AND circuit 44 via a delay circuit 43 having a delay time of, for example, about 10 ms.
The other input terminal of the AND circuit 44 is connected to the line _L1 . 45 is a D flip-flop whose data input terminal D is connected to a high level signal source 46, whose clear input terminal CL is connected to line _L2 , and whose clock input terminal CK is connected to the output terminal of AND circuit 44. . 47 is a monostable multivibrator that outputs a high level signal for a predetermined period in response to the rise of the output of the D flip-flop 45 to a high level signal; its output is sent to the AND circuit 49 via an inverter 48; It is applied to one input terminal and also directly to the buzzer drive circuit 50. The buzzer drive circuit 50 causes the buzzer 51 for notifying completion of extraction of coffee liquid to sound only during a period when a high level signal is input. on the other hand,
The AND circuit 49 is connected to provide its output to the heater drive circuit 4, and the heater drive circuit 4 is configured to operate while a high level signal is input to turn on the output switch 4a. It is.

Note that the other input terminal of the AND circuit 49 is connected to the output terminal of the AND circuit 37.

Next, the operation of this embodiment having the above configuration will be explained. When producing coffee liquid, an amount of water corresponding to the desired number of people is supplied into the water storage tank of the hot water supply mechanism, and with the corresponding amount of coffee beans stored in the case, the lid is placed on the case. , and then place a bottle that stores coffee liquid on the heater of the hot water supply mechanism. Then, in this state, coffee beans are first milled. In this case, when the set switch 18 is turned on and kept in the on state, the count pulse Pc from the frequency divider 17 is
It is applied to the up counter 20 via the AND circuit 19, which adds and counts the counting pulse Pc, and the content of the count is outputted as a digital signal Sn. At this time, as will become clear from the description below, a low level signal is being output from the AND circuit 30 and the transfer gate 22
is conductive, the digital display 21 receives the digital signal Sn, and therefore the digital display 21 receives the digital signal Sn.
The corresponding numbers are “0” → “1” → “2” →
"3"... will be displayed in increasing numbers, so
The operator can display any number such as "12".
When this happens, the on operation of the set switch 18 is released. When the ON operation of the set switch 18 is released in this way, the high level signal is no longer input to the AND circuit 19, and the AND circuit 19 blocks the passage of the counting pulse Pc.
The up counter 20 stops the counting operation, stores the count value "12" as the count result, and outputs a digital signal Sn corresponding to the count value "12". Therefore, at this time, the digital display 21 continues to display "12". After this, when the start switch 25 is turned on, in this case, as will be understood from the description below, a high level signal is output from the inverters 41 and 42, so a high level signal is output from the AND circuit 26, and this high level signal is output from the AND circuit 26. The R-S flip-flop 28 which receives the signal at its set input terminal S is set, and a high level signal which is the first set signal is outputted from its set output terminal Q. However, in such a state, if the lid of the case is not properly attached to the predetermined position, the lid switch 1 is turned off, and the output switch 4a is also turned off, so that the signal extraction point 11 is turned off. From transistor 13
A base current serving as a detection current is not applied to the base of the transistor 13, and the transistor 13 is in an off state. Therefore, a low level signal corresponding to the potential of the low potential side output line 8a of the DC power supply circuit 8 is output to the line _L1 , and the AND circuit 3
1 continues to output a low level signal, and therefore the R-S flip-flop 33 also maintains the reset state and outputs a low level signal from its set output terminal Q. As described above, when a high level signal is output from the R-S flip-flop 28, the high level signal is applied to one input terminal of the AND circuit 30 via the delay circuit 29, and Since the low level signal from the R-S flip-flop 33 is applied to the input terminal of the transfer gate 24 via the inverter 34, the AND circuit 30 outputs a high level signal as a determination signal. conducts. Then,
The information signal Sd from the storage unit 23 is input to the digital display 21 and this is "LId" (see Figure 2).
This will notify you that the lid is not attached properly. In addition, when the start switch 25 is turned on with the lid not properly attached, the R-
Since the S flip-flop 33 does not output a high level signal, the monostable multivibrator 35 is not driven, and the transfer gate 39
will maintain a non-conducting state. Therefore, the digital signal Sn is not input to the data input terminal D of the down counter 38, and the down counter 38 continues in its initial state, that is, the state in which its count value is "0" and it outputs a low level signal. Therefore, the output switch 7a is not turned on by the motor drive circuit 7, and
Thus, the de-energized state of the motor 6 is maintained. That is,
The mill operation will not start if the lid is not properly attached. On the other hand, when the case lid is normally attached to the predetermined position, the lid switch 1 is on and the output switch 4a is off, so every half-wave period when the output terminal 5b side of the AC power source 5 is at a high level. A base current is supplied from the signal extraction point 11 to the transistor 13, and the transistor 13 is turned on periodically according to the frequency of the AC power supply 5. For this reason,
A high level signal is intermittently outputted to the line _L1 each time the transistor 13 is turned on. Therefore,
If the start switch 25 is turned on when the lid is not installed normally, and then the lid is reinstalled normally based on the display "LId" on the digital display 21 as described above, and the lid is installed normally. When the start switch 25 is turned on in a state where the
1 outputs a high level signal as a trigger signal, the R-S flip-flop 33 is set and a high level signal as a second set signal is output from its set output terminal Q. Then, the monostable multivibrator 35 driven by this high level signal outputs a high level signal for a short time to make the transfer gate 39 conductive, so that the digital signal stored in the up counter 20 is
Sn is applied to the data input terminal D of the down counter 38, and the down counter 38 presets the numerical value "12" corresponding to the input digital signal Sn, and outputs a high level signal from the output terminal P to start the motor. The drive circuit 7 is operated. This turns on the output switch 7a and energizes the motor 6, which rotates the cutter and starts grinding the coffee beans in the case. At the same time, a high level signal is applied to one input terminal of the AND circuit 40, and the counting pulse Pc applied to the other input terminal of the AND circuit 40 passes through it. Counting pulse Pc
The down counter 38, which receives this at its clock input terminal CK, starts a subtraction counting operation.
Such a subtraction counting operation is started based on the preset value "12", and the count value becomes "12".
→ "11" → "10"... It will decrease sequentially. When the count value of the down counter 38 reaches "0", a low level signal is output from the output terminal P instead of a high level signal, so the motor drive circuit 7 is stopped and its output is The switch 7a is turned off, and the motor 6
At the same time as the power is cut off and grinding of the coffee beans is completed, the AND circuit 40 is turned off and the input of the counting pulse Pc to the down counter 38 is stopped. Therefore, the time it takes for the count value of the down counter 38 to go from "12" to "0" is 12 seconds because the output cycle of the count pulse Pc is 1 Hz, and therefore the time required for the count value of the down counter 38 to go from "12" to "0" is 12 seconds. The time (mill time) is controlled to 12 seconds.

Incidentally, as mentioned above, when a high level signal is output from the set output terminal Q of the R-S flip-flop 33, the high level signal is outputted from the inverter 34.
Since the signal is inverted and input to the AND circuit 30, the AND circuit 30 outputs a low level signal.Therefore, the transfer gate 22 is made conductive and the digital display 21 is input to the up counter 2.
Numerical value "12" corresponding to digital signal Sn from 0
will be displayed. Furthermore, before the start switch 25 is turned on, the R-
Since the S flip-flop 28 is outputting a low level signal, this low level signal is sent to the delay circuit 2.
The AND circuit 30 which receives the signal via the signal line 9 outputs a low level signal as described above. Furthermore, the delay circuit 29 is provided to compensate for the intermittent nature of the high level signal output to line _L1 .

Now, when the milling operation is completed as described above, the operation automatically shifts to the dripping operation. That is, when the down counter 38 outputs a low level signal and the milling operation is completed, the inverter 41 that has received the low level signal outputs a high level signal, and this high level signal is sent to the AND circuit 37.
is applied to one input terminal of . At this time, AND
A high level signal is input to the other input terminal of the circuit 37 via the delay circuit 36 at the time when the high level signal is output from the flip-flop 33 (in other words, at the time when the milling operation is started). Therefore, as a result, the AND circuit 37 outputs a high level signal in place of the previous low level signal at the same time as the milling operation ends.
This high level signal is passed through the delay circuit 43.
In addition to applying it to one input terminal of the AND circuit 44,
It is also applied directly to the other input terminal of the AND circuit 49.
In this case, at the moment when a high level signal is output from the AND circuit 37, a low level signal is applied to one input terminal of the AND circuit 44 (the input terminal connected to the delay circuit 43), and the AND circuit 44 receives a low level signal.
4 outputs a low level signal, the D flip-flop 45 assumes an initial state (clear state) and outputs a low level signal from its output terminal Q, and the monostable multivibrator 47 is also in a non-driven state. The inverter 48 outputs a low level signal, and the inverter 48 that receives this outputs a high level signal. Therefore, the AND circuit 49 receives the high level signal at the moment the AND circuit 37 outputs it.
outputs a high level signal, the heater drive circuit 4 is operated and the output switch 4a is turned on.
As a result, the heater 2 is energized and generates heat. When the output switch 4a is turned on in this way, the base current is no longer supplied from the signal extraction point 11 to the base of the transistor 13, and the transistor 13 is turned off, so that a low voltage is applied to the line _L1 . The level signal is now output and therefore the AND connected to line L ₁
A low level signal is now applied to the input terminal of the circuit 44. Here, the delay time of the delay circuit 43 is longer than the delay time from the time when a high level signal is output from the AND circuit 37 to the time when the output switch 4a is turned on and a low level signal is output to line _L1 . For example, it is set to 10 ms, and therefore, when a high level signal is output from the AND circuit 37, the delay effect of the delay circuit 43 causes a situation where the high level signal is simultaneously input to both input terminals of the AND circuit 44. It is prevented. Due to this action, the D flip-flop 4
5 is performed while maintaining the initial state. Now,
As described above, when the heater 2 is energized and generates heat, the water in the heater supplied from the water storage tank flows into the heater 2.
The hot water thus produced is supplied into the case by its boiling pressure and extracted as coffee liquid, and the extracted coffee liquid is poured into the bottle placed on the heater. The water is stored downstream. When all the water in the water storage tank is consumed by such coffee liquid extraction or dripping operation, the temperature of the heater will rise rapidly due to no heat exchange between the heater and the water. The bimetal switch 3 detecting this turns off and the heater 2 is cut off, thereby completing the dripping operation. When the dripping operation is completed as described above, that is, when the bimetal switch 3 is turned off, the signal output point 11 is connected to the base of the transistor 13.
Then, the base signal is again applied, turning on the transistor 13, and a high level signal is intermittently output to the line _L1 .
Then, a high level signal is input to both input terminals of the AND circuit 44, and the AND circuit 44 outputs a high level signal, so the D flip-flop 45 is triggered and outputs a high level signal, and in response to this, the D flip-flop 45 is triggered and outputs a high level signal. Monostable multivibrator 47
outputs a high level signal for a predetermined period. Therefore, the buzzer drive circuit 50 is turned on for a predetermined period, and the buzzer 51 sounds during this period.
This is the notification that the dripping operation has been completed. Note that during the period when the buzzer 51 is ringing, that is, during the period when the monostable multi-valve generator 47 is outputting a high-level signal, the high-level signal is inverted to a low-level signal by the inverter 48.
Since it is input to the AND circuit 49, the AND circuit 4
9 starts outputting a low level signal, and the operation of the heater drive circuit 4 is temporarily stopped.
After the above-described dripping operation is completed, the bimetal switch 3 is intermittently turned on and off to control the heater 2 to be turned on and off, and the coffee liquid in the bottle is kept warm by the heater.
To stop such heat retention, the stop switch 27 is turned on. Then, due to the high level signal outputted to line _L2 due to this ON operation, the R-S flip-flops 28, 33,
Town counter 38 and D flip-flop 45
are all reset or cleared, and in particular, the AND circuit 3 is reset by resetting the R-S flip-flop 33.
7, a low level signal is output from the AND circuit 49 at the subsequent stage, and the heater drive circuit 4 is stopped, and the heater 2 is cut off, that is, the heat retention is stopped. . Also,
During the aforementioned drip operation, the stop switch 27
When the heater 2 is turned on, the heater 2 is similarly cut off and the dripping operation is stopped midway. Furthermore, when the stop switch 27 is turned on during mill operation, the count value of the down counter 38 is cleared to "0" and a low level signal is output from now on, so the motor drive circuit 7 is stopped. The motor 6 is cut off, and the mill operation is stopped midway. Note that the delay circuit 36 prevents a situation in which a high level signal is input to both input terminals of the AND circuit 37 at the same time at the start of the mill operation, that is, at the moment when a high level signal is output from the R-S flip-flop 33. It is set up for the purpose of

According to the present embodiment described above, when the lid is not attached normally, when the start switch 25 is turned on, the start of the mill operation is inhibited, and a message indicating that the lid is not attached properly is suppressed. It is convenient to use because it can be displayed, and since the display is also used by the digital display 21 for displaying the mill time set in advance, it is advantageous in terms of circuit configuration. When the lid is properly reattached, the milling operation starts immediately, and the milling operation can be performed reliably for a preset period of time, so there is no risk of a mill shortage as described in the conventional example. Furthermore, there is no need to perform an operation to reset the mill time, and there is no risk that the operation will become complicated. In particular, in coffee makers that have both a hot water supply mechanism and a milling mechanism, the dripping operation is automatically started following the milling operation, so if the coffee beans are insufficiently milled, a sufficient amount of coffee liquid will be produced. Although a situation may occur where it becomes impossible to obtain the desired result, this embodiment can reliably prevent such a situation.

According to the present invention, as is clear from the above explanation, it is possible to prevent the start of the milling operation when the lid is not attached to the normal position, and even if the lid is forgotten to be attached, the coffee beans can be milled in advance. It is possible to provide a coffee mill that can be reliably executed for a set period of time, has no risk of running out of mills, and is free from the risk of complicated operations.

[Brief explanation of the drawing]

FIG. 1 is an electrical configuration diagram showing an embodiment of the present invention, and FIG. 2 is a front view showing an example of one state of a digital display in the embodiment. In the figure, 1 is a lid switch, 6 is a motor, 10 is a detection circuit, 21 is a digital display (warning display and mill time display), 25 is a start switch, 2
7 is a stop switch (reset switch), 2
8 is an R-S flip-flop (first memory circuit);
30 is an AND circuit (determination circuit), 31 is an AND circuit (gate circuit), 33 is an R-S flip-flop (second memory circuit), and B is a mill time control circuit.

Claims (1)

[Scope of Claims] 1. In an apparatus for grinding coffee beans stored in a case using a cutter rotated by a motor, when set by a start switch, the set state is memorized and retained and a first set signal is output. a first memory circuit that detects when the lid of the case is normally attached and outputs a detection signal; and a detection circuit that outputs a detection signal when the first set signal and the detection signal are input at the same time. a gate circuit that outputs a second set signal; a second memory circuit that stores and holds the set state when set by the trigger signal and outputs a second set signal; and a second memory circuit that outputs a second set signal when the second set signal is output. and a mill time control circuit for energizing the motor for a preset time. 2. A determination circuit is provided that outputs a determination signal when the second set signal is not output while the first set signal is output, and also indicates that the lid is not properly attached when the determination signal is output. The coffee mill according to claim 1, further comprising a warning display for displaying a warning. 3. Claims characterized in that the mill time control circuit has a mill time display that displays a preset motor energization time, and the mill time display also serves as a warning display. The coffee mill according to item 2. 4. The coffee mill according to claim 1, further comprising a reset switch for resetting the set times of the first memory circuit, the second memory circuit, and the mill time control circuit to their initial states.