JPS59166114A - Control of rice cooker - 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 comprises a microcomputer-based control circuit for controlling multiple processes such as preheating and rice cooking based on pot temperature information etc. from a temperature sensor. This invention relates to a rice cooker control method.

[Technical background of the invention and its problems]

Conventionally, a control circuit configured with a microcomputer performs a preheating process to preheat the pot and allow the rice in the pot to absorb moisture sufficiently, and subsequently performs a rice cooking process, a steaming process, and a warming process. There is a rice cooker that performs the steps in this order, and in this case, each step is controlled based on pot temperature information from a temperature sensor, a clock signal, etc. However, in such a configuration, the preheating process to the warming process are always performed every time rice is cooked according to a program stored in advance in the control circuit. However, there was a problem in that it was not possible to meet the needs of rice cookers when they wanted to perform only the steaming process for re-steaming rice, etc.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and its object is to provide a preheating process and a subsequent rice cooking process by a control circuit comprising a microcomputer.

When controlling a rice cooker that is configured to sequentially perform a heating process and a warming process, any five of the preheating, rice cooking, heating, and warming processes can be performed by simply repeating the operation of the external operating means. To provide a method for controlling a rice cooker which can start a process and has effects such as improving the usability of the rice cooker.

[Summary of the invention]

The present invention provides a preheating process and a subsequent rice cooking process that are controlled by a control circuit comprised of a microcomputer.

In a rice cooking AG in which a steaming process and a warming process are performed sequentially, each process is configured to be able to be advanced or reversed each time an external operating means is operated, and an arbitrary process can be performed depending on the temperature. This is how it was done.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, 1 is a rice cooker main body consisting of an inner case 2, an outer case 3, etc., 4 is a lid, 5 is a pot housed in the inner case 2, 6 is a heater for cooking rice, and 7 is a heater for keeping warm. . 8
is a cup-shaped heat-sensitive part provided so as to be in contact with the outer bottom of the pot 5 in a thermally conductive manner, and a thermistor 9 serving as a temperature sensor is thermally attached inside the cup-shaped heat-sensitive part. h4 is emitted so that the temperature of the pot 5 can be detected.

Reference numeral 10 denotes a case disposed at the outer bottom of the rice cooker main body 1, and a control circuit 11 and the like whose circuit configuration is shown in FIG. 2 and FIG. Further, 12 is a light emitting diode for displaying a preheating process, 13 is a light emitting diode for displaying a rice cooking process, 74 is a light emitting diode for displaying a heating process, and 15 is a light emitting diode for displaying a warming process.

Next, in FIG. 2, a plug 16 is inserted into a power outlet (not shown), and a rice cooking heater 6, a heat-retaining heater 7, and relay switches 17 and 18 are connected between both terminals of the plug as shown. Note that the relay switch 17.
Reference numerals 18 and 18 are of a normally open type, which are turned on only when the corresponding excitation coils 19 and 20 are energized. 21 is a DC power supply circuit, which includes a transformer 22.21 that reduces the voltage between both terminals of the plug 16. Bridge type full wave rectifier 23. Smoothing capacitor 241 Consists of a constant voltage circuit 25 of a well-known structure, which outputs a DC low voltage between lines L1 and L2 with line L1 (III) having a high potential. 26 is connected to the thermistor 9.
This is a temperature detection circuit that detects a change in resistance value (that is, temperature information of the pot 5), and this is a temperature signal Sa corresponding to the temperature of the pot 5.
is output and applied to the input terminal 11 of the control circuit 11.

27 is an automatic return type push button switch which is an external operation means, and this is connected to the line L1 and the control circuit 110 input terminal.
It is connected between the two. Reference numeral 28 denotes a drive circuit consisting of an inverter 29.30 and the excitation coil 19.20.
2 to 15 as well as the line L1 and the output terminal Q of the control circuit 11.
1 to Q6 as shown in the figure.

The control circuit 11, which is provided to be supplied with power from the lines L+ and L2, is composed of a microcomputer, and its configuration will be described below with reference to FIG.

That is, 35 is a pulse generating circuit which receives the voltage signal S1 inputted to the input terminal I2 every time the push button switch 27 is turned ON via the chattering prevention circuit 36. Then push button switch 2
7 is turned on), a clock pulse Pc is output. 67 is a quinary counter that counts pulses, and when the power is turned on, the count value is initialized, and when the count value is "0", the logic value "1" is output from the output terminal An.
A signal is output, and the count values are rIJ and r2J in the same way.

At the time of each state in r 3 J, r 4 J, the corresponding output terminals A+, A2, Aa, and A4 each have a logical i value of "1".
This is a configuration that outputs a ” signal. 38 and 39 are counters that start counting oscillation pulses from an oscillator (not shown) when receiving a trigger signal, and this counter sequentially outputs the counting chamber. Comparing circuits 40 to 45 output a logic value "1" signal only when the input value to input terminal A is greater than or equal to the input value to input terminal B, and output a logic value rOJ signal in other states. Reference numeral 46 denotes a first storage section, which stores, for example, 45 degrees in the dimension of the temperature signal Sa.
A preheating temperature value D46 corresponding to CK is stored.

Reference numeral 47 denotes a second storage section, which stores a humidity value D47 for rice cooking that is aimed at, for example, 110° C. in the dimension of the temperature signal Sa. Reference numeral 48 denotes a sixth storage unit, which stores the dimension of the temperature signal Sa, for example, 100°C.
A temperature value D48 for double cooking corresponding to is stored.

49 is a fourth storage section, which stores a temperature value D4 for keeping warm corresponding to, for example, 72°C in the dimension of the temperature signal Sa.
9 is memorized. Reference numeral 50 denotes a fifth storage section, which stores a preheating time value T50 corresponding to the count value when, for example, 5 minutes have passed since the counter 68 started counting. Reference numeral 51 denotes a sixth storage section, which stores an irregularity time value T51 corresponding to the count value when, for example, 15 minutes have passed since the counter 39 started counting. Trigger circuits 52 to 55 output a trigger pulse Pt consisting of a logic value "1" signal in synchronization with the rise of the input signal. Then, the pulse generating circuit 35 and the quinary counter 37 described above are connected. counter 58
．． 39. Comparison circuits 40-45. Each of the storage units 46 to 51 and the like is connected to an AND circuit 56 to 62 . When inputting to the control circuit 11 together with the OR circuit 65°64, inverters 65 and 66, and inverter buffer circuits 67 to 72, 1. The terminals I+ and Iz are connected as shown in the figure between the output terminals Q1 to Q6.

Next, the operation of the above-mentioned structure will be explained with reference to a temporal change characteristic diagram of the temperature of the pot 5, which is not shown in FIG.

Now, when the lid 4 is closed with a predetermined amount of rice and water stored in the pot 5, and the plug 16 is then inserted into a power outlet (not shown), the DC power circuit 21 is connected to the line L1. A constant DC voltage is output between L2 and the control circuit 11 is powered on. When the power is turned on in this way, the count value of the quinary counter 37 is initialized, so the quinary counter 37 outputs a logic value "1" signal only from its output terminal Ao (which is in an open state). exhibit a condition. In this state, when the push button switch 27 is turned on only once at time t1 in FIG.
Since one clock pulse Pc is output, this clock pulse Pc is
The count value of the quinary counter 37 received via the R circuit 63 is stepped to "1", and a logic value "1" signal is output from the output terminal A1 of the quinary counter 37. Then, one input terminal of the A N D circuit 57 receives a logical value of “1”.
" signal is now input, and at this point, the temperature of the pot 5 is below 45 degrees Celsius, and the comparison circuit 41 that compares the temperature signal Sa and the preheating temperature value D46 has a logic value of "0".
Since the signal is being output, the other input terminal of the AND circuit 57 also has the logical value "1" inverted by the inverter 65.
” is entered. Therefore, this AND circuit 57
The logical iN value r I J signal output from the OR circuit 6
4, the output terminal of the inverter buffer circuit 72 (and thus the output terminal Q2 of the control circuit 11) receives the logical value "
0'' signal level (low level), the excitation coil (V19) is energized and the relay switch 17 is turned on, causing the rice cooking heater 6 to continuously generate heat and start a preheating process. As the temperature of the pot 5 (and the water inside it) increases due to the start of such a preheating process,
When the temperature of the pot 5 reaches 45°C (time t2 in Fig. 4)
), the comparator circuit 41 outputs a logic value "1" signal, and therefore the output of the AND circuit 57 becomes a logic value "1" signal.
0'' signal, and the inverter buffer circuit 72 outputs the logical value 1' I Jli ('ff).

As a result, the excitation coil 19 is cut off, and the rice cooking heater 6 is also cut off.After this, when the temperature of the pot 5 decreases and becomes lower than 45°C, the comparator circuit 41 outputs a logic value of "1".
'' signal is output to re-energize the rice cooking heater 6, and by repeating this operation, the temperature of the pot 5 and, by extension, the water temperature in the pot 5 is maintained at about 45°C. On the other hand, when the temperature of the pot 5 reaches 45'OK for the first time, that is, when the comparator circuit 41 first outputs the logic value "1" signal, both input terminals of the AND@J path 58 A logic value "1" signal is applied from the output terminal A1 of the forward counter 37 and the comparator circuit 41, respectively, and the output of the A N D @ J path 58 is inverted to a logic value "1" signal, so that a trigger is generated from the trigger circuit 52. The pulse Pt is output and the counting operation of the counter 38 is started. Therefore, when 5 minutes have passed since the temperature of the pot 5 first reached 45° CK (time t3), the comparator circuit 42 that compared the count value of the counter 38 and the preheating time value Tso outputs a logic value "1" signal. Therefore, the trigger pulse Pt is output from the trigger circuit 56. Then, the count value of the quinary counter 67 that receives this trigger pulse Pt via the OR circuit 66 is stepped to "2", and the quinary counter 67 inverts the output of the output terminal A1 to the logical value rOJ signal. At the same time, the output of the output terminal A2 is set to the logical value "1".
” to reverse the signal. Therefore, AND circuit 57.58
is the inverter 65. Passage of each output signal of the comparison circuit 41 is blocked, and at the same time, a logic value "1" signal is input to one input terminal of each AND circuit 59, 60, and the corresponding A
N D UgJ path 59.60 is the inverter 66,
Each output signal of the comparison circuit 45 is allowed to pass through. At this point, the temperature of the pot 5 is below 110°C, and the comparator circuit 46 that compares the temperature signal Sa and the rice cooking temperature value D47 outputs a logic value "0" signal.
The AND circuit 59 also receives the logic value "1" signal inverted by the inverter 66 at the other input terminal. Therefore, the output terminal of the inverter buffer circuit 72 falls to a low level due to the logical value "1" signal output from the A N D circuit 59, and the rice cooking heater 6 is energized in the same way as described above, thereby starting the preheating process. The process moves on to the rice cooking process. In addition, during the preheating process, the output terminal of the inverter buffer circuit 71 (as a result, the output terminal Q3 of the control circuit 11) falls to a low level due to the logic value "1" signal from the output terminal A1 of the quinary counter 37, so that the preheating process The display light emitting diode 12 is energized and lit.

Therefore, the temperature of the pot 5 becomes 115 as the rice cooking process is executed.
When the temperature reaches °C (time 14), the comparison circuit 43 that compares the temperature signal Sa and the rice cooking temperature FiT47 outputs a logic value of "1".
'' signal, the output of the AND circuit 59 is inverted to a logic value rOJ signal, and the inverter buffer circuit 72 outputs a logic value "1" signal. As a result, the excitation coil 19 and, in turn, the rice cooking heater 6 are cut off, thereby ending the rice cooking process and proceeding to the uneven process. Incidentally, during the rice cooking process, the logic value "1" signal from the output terminal A2 of the quinary counter 37 causes the output terminal of the inverter buffer circuit 67 (and thus the output terminal Q of the control circuit 11 to be
4) falls to a low level, the light emitting diode 13 for displaying the rice cooking process is turned on.

Now, at the end of the rice cooking process, a logical value "1" signal is applied to both input terminals of the AND circuit 60 from the output terminal A2 of the quinary counter 67 and the comparison circuit 43, and the AND circuit 60 Since the output is inverted to a logical ir 1 J signal, the trigger circuit 54 outputs a signal Pt. Then, the counting operation of the counter 39 is started in synchronization with the rise of the trigger pulse Pt, and the count value of the quinary counter 37 that has counted the trigger pulse Pt is stepped to "3". As a result, the quinary counter 6
7, in order to invert the output of the output terminal A2 to a logic value "0" signal and to invert the output of the output terminal A3 to a logic value "1" signal, the AND circuits 59 and 60 respectively invert the inverter 66 and the comparison circuit 45. Passage of each output signal is blocked, and at the same time, a logic value "1" signal is input to one input terminal of each AND circuit 61, 62, and the AND circuit 6
1.62 allows each output signal of the ratio s2 circuit 44 and 45 to pass through. When the temperature of the pot 5 becomes lower than 100°C at time t5 after the steaming process has started in this way, a logic value of "1" is output from the comparator circuit 45 that compares the temperature value @Sa and the double-cooking temperature value T48. ” signal is output, and this logical value “1” signal passes through the AND circuit 62 and is input to the inverter buffer circuit 72. For this reason,
The rice cooking heater 6 is energized again to perform so-called double cooking heating, and in such double cooking heating, the temperature of the pot 5 reaches 100°C and the output of the comparison circuit 45 is inverted to a logic value "0" signal. During the steaming process, twice-cooking and heating are performed multiple times. Then, when 15 minutes have passed since the time t4 when the uneven stroke transition was made (time t
6), Count value of counter 59 and time for irregularity! T5j
The comparison circuit 44 that compared the logic El! Since the fifr 1J signal is output, this logical value "1 signal 8 passes through the AND circuit 61, and the trigger circuit 55 outputs the trigger pulse Pt.
The count value of the quinary counter 37 that received t is stepped to "4". Then, the quinary counter 37 outputs its output terminal A.
The AND circuits 61 and 62 invert each output signal of the comparison circuits 44 and 45 to invert the output of output terminal A4 to a logic value "0" signal and invert the output of output terminal A4 to a logic value "1" signal. Now blocks the passage of AND at the same time
A logic value "1" signal is input to one input terminal of the circuit 56, and the AND circuit 56 allows the output of the comparator circuit 40 to pass, and the process proceeds to the next warming process. It should be noted that during the uneven stroke, the output terminal A3 of the quinary counter 37 drops to a low level due to the 1 J signal, so the uneven stroke occurs. Then, the light emitting diode 14 for displaying the stroke is energized and lit.

In the warming process, when the temperature of the pot 5 becomes 72°C or less, the comparison circuit 40 that compares the temperature signal 8a and the temperature value T49 for keeping warm outputs a logic value "1" signal, so this logic value The "1" signal passes through the AND circuit 56 and is applied to the inverter buffer circuit 7D. Then, the output terminal of the inverter buffer circuit 70 (and the output terminal Q+ of the control circuit 11) falls to the 4- level, so the excitation coil 20 is energized, the relay switch 18 is turned on, and the insulating heater 7 is energized and generates heat. be done. By controlling the current supply to the heat retaining heater 7 by the comparator circuit 40° inverter buffer circuit 70, etc., the pot 5
temperature is maintained at around 72°C. In addition, during the warming process, the logical value from the output terminal A4 of the -quinary counter 37 is
1'' signal causes the output terminal of the inverter buffer circuit 69 (output terminal Q6 of the control circuit 11 in Hikime) to fall to low level, so the light emitting diode 1 for indicating the warming process
5 is energized and lit. Also, after this, the push button switch 27
When the pulse generation circuit 35 is turned on, the pulse generation circuit 35
Since the count value of the quinary counter 37 that counts the clock pulses Pc output from the quinary counter 67 is stepped to "o", the outputs of the output terminals A1 to A4 of the quinary counter 67 are all made into logic "0" signals. The warming process is stopped.

As described above, when the push button switch 27 is turned on only once after the control circuit 11 is powered on, the preheating, rice cooking, uneven heating, and warming steps are sequentially executed. After the power is turned on, the push button switch 27 is set to 2.
When the ON operation is performed twice, two clock pulses PC are output from the pulse generation circuit 35 and the count value of the quinary counter 67 is set to "2".
A logical value "1" signal is output from the output terminal A2 of the rice cooker, and as a result, the preheating process is skipped and the rice cooking process is started immediately. If the pushbutton switch 27 is turned on six times after the power is turned on to the control circuit 11, the count value of the quinary counter is stepped to "5", so the preheating process and the rice cooking process are skipped and the steaming process is started immediately. If the push-button switch 27 is turned on four times, the warming process is immediately started, skipping the preheating process, rice cooking process, and uneven cooking process.

In the above embodiment, the steps of preheating, rice cooking, etc. are sequentially advanced each time the push button switch 27 is turned on, but the steps are reversed each time the push button switch 27 is turned on. Even if it's good lA.

〔Effect of the invention〕

According to the present invention, as is clear from the above description, when a rice cooker configured to sequentially execute a preheating process, a subsequent rice cooking process, a steaming process, and a warming process is controlled by a control circuit composed of a microcomputer. Preheating, cooking, and cooking rice can be done by simply repeating the operation of the external operating means.

Any one of the warming steps can be started, and excellent effects such as improved usability of the rice cooker can be achieved.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway vertical cross-sectional view, FIG. 2 is an overall circuit configuration diagram, and FIG.
The figure is a circuit configuration diagram of the main part, and FIG. 4 is a temperature characteristic curve diagram for explaining the operation. In the figure, 5 is a pot, 6 is a rice cooking heater, 9 is a thermistor (temperature sensor), 11'd is a control circuit, and 27 is a push button switch (external operating means). Figure 1

Claims (1)

[Claims] 1. A preheating process, a rice cooking process, and a steaming process for preheating a pot based on pot temperature information etc. from a temperature sensor. A control circuit for a rice cooker in which a control circuit for sequentially executing heat retention processes is configured by a microcomputer, characterized in that each process can be advanced or reversed each time an external operating means is operated. Method.