JP2000300431A - Electric rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric rice cooker capable of boiling rice deliciously in a short period by heating rice straightway to be boiling up with high caloric force. SOLUTION: This electric rice cooker has a heating control means for controlling the heating quantity of a heating means (work coil 10). The work coil 10 is controlled to heat rice with the highest heating quantity in the boiling-up process from the completion of the water-absorbing process till the temperature of the rice cooker detected by a temperature detecting means increases to or near the boiling point, and the heating quantity of the work coil 10 is controlled based on the quantity of the rice in the rice cooker after the temperature reaches the boiling point or near the boiling point. The electric rice cooker boils up rice straightway with high caloric force after the completion of water absorption till boiling with the work coil 10 heated/controlled with the highest heating quantity, then heats the rice with a heating quantity corresponding to the quantity (i.e., the number of cups) of the rice.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric rice cooker capable of cooking with high heat.

[0002]

2. Description of the Related Art Generally, when cooking rice with an electric rice cooker,
The amount of heating by the heating means is controlled in accordance with a water absorption step of absorbing water into rice, a cooking step of cooking rice, and a steaming step of steaming the cooked rice. At this time, since it is necessary to adjust the amount of heating until the completion of the cooking and the amount of heating in the steaming step according to the amount of the rice (hereinafter referred to as the total number), the amount of the rice is determined before the completion of the cooking. In other words, it is necessary to perform a total number determination.

[0003] As a conventional method of judging the total number, a heating means is turned on / off within a predetermined time during the cooking process (for example, from the end of the water absorption process to the boiling).
There is a method of turning OFF and making a determination based on the number of times.

[0004]

[Problems to be Solved by the Invention] By the way, to cook rice deliciously for a long time, it is necessary to start with "Chorochoro, Nakapapa"
It has been said that it is better to heat to a boil at once with strong heat.

However, if the total number is determined during the cooking process as described above, the amount of heating decreases at the time of the total number determination. And the time required for cooking rice becomes longer.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to make it possible to cook delicious rice in a short time by heating it to a boil with high heat. is there.

[0007]

According to the first aspect of the present invention, there is provided a rice cooker body for removably storing a rice cooker, a heating unit for heating the rice cooker, An electric rice cooker comprising a lid of a rice cooker main body, and a temperature detecting means for detecting a temperature of the rice cooker, wherein a water absorption step, a cooking step and a steaming step are configured to control the energization of the heating means. In the cooking step during which the rice cooker temperature detected by the temperature detecting means rises to or near the boiling point after completion of the water absorption step, the heating means is controlled to be heated at the maximum heating amount, and the boiling point or the boiling point is near. After that, a heating control means for controlling the amount of heating by the heating means according to the amount of rice in the rice cooker is additionally provided.

[0008] With the above-described configuration, during the period from the end of water absorption to the time of boiling, the heating means is controlled to be heated at the maximum heating amount and cooked at once with high heating power, and thereafter the amount of rice (ie, (Combination number). Therefore, delicious rice can be cooked in a short time.

As in the invention of claim 2, claim 1
In the electric rice cooker described above, the determination of the amount of rice in the rice cooker is performed while the heating control unit controls the heating at the boiling point or near the boiling point after heating the heating unit at a maximum heating amount. In this case, the determination of the amount of rice (that is, the determination of the total number) does not adversely affect the amount of heating during cooking.

[0010] As in the invention of claim 3, claim 1
In the electric rice cooker described above, when the determination of the amount of rice in the rice cooker is performed in the water absorption step, the determination of the amount of rice (that is, the total number) is determined by the amount of heating at the time of cooking. No adverse effects.

As in the invention of claim 4, claim 2
In the electric rice cooker described above, the temperature detected by the temperature detecting means is maintained at the boiling point while the heating control means controls the heating at or near the boiling point after heating the heating means at the maximum heating amount. The number of peaks and / or valleys generated by repetition of temperature rise and temperature drop generated when controlling the energization of the heating means so as to cause the rice within the rice cooker to be detected within a predetermined time. When the amount is determined, it is possible to easily determine the amount of rice (that is, determine the total number).

As in the invention of claim 5, claim 3
In the electric rice cooker described above, in the water absorption step, a peak caused by repetition of a temperature rise and a temperature fall that occurs when controlling the power supply to the heating means so as to maintain the temperature detected by the temperature detection means at the water absorption temperature. Alternatively, when the number of valleys is detected within a predetermined time to determine the amount of rice in the rice cooker, the determination of the amount of rice (that is, the total number determination) can be easily performed. It can be carried out.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

First Embodiment FIG. 1 shows an electric rice cooker according to a first embodiment of the present invention.

This electric rice cooker has a rice cooker 3 for cooking rice inside.
A rice cooker body 1 having a double structure and having a space 4 and a lid 2 for opening and closing the upper opening of the rice cooker body 1 in an openable and closable manner.

The rice cooker main body 1 has a body 5 serving as an outer wall.
a and a bottom part 5b serving as a bottom wall, an outer case 5 made of an integrally molded product of synthetic resin, a protection frame 6 having a bottom and made of synthetic resin serving as an inner peripheral wall, and an upper end of the protection frame 6 A synthetic resin shoulder member 7 is connected to the upper end of the outer case 5, and the space 4 is surrounded by the outer case 5, the protective frame 6 and the shoulder member 7. In addition,
The rice cooker 3 is stored in the protective frame 6 so as to be able to be taken out.

A sensor hole 9 is formed in the center of the bottom surface of the protection frame 6 to face a center sensor 8 acting as a temperature detecting means. .

An annular electromagnetic induction coil (hereinafter, referred to as a work coil) 10 acting as a heating means at the time of cooking rice so as to surround the sensor hole 9 is disposed between the bottom surface of the protective frame 6 and the side peripheral surface from the bottom surface. Are provided corresponding to the curved portions. The work coil 10 generates an alternating magnetic field, generates an eddy current as an induced current in the rice cooker 3 by electromagnetic induction of the alternating magnetic field, and heats the eddy current using the resistance heat of the eddy current. It has been. The rice cooker 3 is made of a material (for example, a magnetic material) capable of generating an eddy current by the work coil 10.

The work coil 10 includes a coil die 11 fixed to the bottom surface of the protection frame 6 and the protection die 6.
It is sandwiched between the bottom surface. Reference numeral 12 denotes a ferrite core, which has a function of blocking so that the magnetism of the work coil 10 does not affect the underlying devices.

A center sensor 8 is provided in the sensor hole 9 so as to contact the bottom of the rice cooker 3. Further, on the side peripheral surface of the protective frame 6, a heat retaining heater 13 acting as a heating means at the time of keeping the temperature is attached.

On the bottom of the rice cooker main body 1 (ie, the bottom 5b of the outer case 5), electronic components such as a power transistor for controlling the energization of the work coil 10 and a rectifying diode bridge (not shown) are provided. An electronic component cooling fan 14 that sends cooling air under pressure is provided. An air inlet 15 is formed on the bottom wall of the rice cooker main body 1 (specifically, on the bottom 5 b of the outer case 5) so as to face the electronic component cooling fan 14.

On the other hand, the lid 2 is composed of an upper plate 16 made of synthetic resin constituting the outer surface and a lower plate 17 made of synthetic resin constituting the inner surface.
A heat insulating material 19 is provided in a space 18 surrounded by.

The lid 2 is attached to the rice cooker main body 1 via a hinge unit 20 formed on one side of the shoulder member 7 so as to be rotatable and detachable.

At the center of the lid 2, there is formed a tubular portion 21 which is suspended from the upper plate 16. Inside the tubular portion 21, steam generated during rice cooking is discharged to the outside. Steam cap 2 having a steam discharge passage 22 for
3 is detachably attached. In the steam cap 23, a ball valve 24 acting as a pressure regulating valve is provided. At the lower end of the steam cap 23,
A radiator plate 25 made of a good heat conductor (for example, aluminum alloy) for sealing the opening 3a of the rice cooker 3 when the lid 2 is closed is attached. Reference numeral 26 denotes a steam inlet to the steam cap 23, 27 denotes a steam outlet from the steam cap 24, 28 denotes a steam port formed in the heat sink 25,
Reference numeral 29 denotes a seal packing for sealing between the periphery of the heat radiating plate 25 and the opening 3a of the rice cooker 3, and reference numeral 30 denotes a seal packing for sealing between the heat radiating plate 25 and the lid lower plate 17.

The shoulder member 7 is provided with a shoulder heater 31. When the lid 2 is closed, the outer peripheral edge of the radiator plate 25 is pressed against the shoulder heater 31, and the radiator plate 25 is Heating is performed by heat conduction from the heater 31. The shoulder heater 31 includes a heater ring 32 having an inverted U-shaped cross section and a heating element 3 disposed in the heater ring 32.
It consists of three.

The lid 2 is located inside the heat radiating plate 25, and is inward from the opening 3 a of the rice cooker 3 with a space interposed between the lid 2 and the heat radiating plate 25. And a rice cooker lid 34 made of a good heat conductor which is supported so that its outer periphery is close to the inner peripheral surface of the rice cooker 3. The rice cooker lid 34 is attached to a seal packing 36 which is detachably fitted to a support shaft 35 projecting downward from the center of the steam cap 23.

A side part (for example, in the rice cooker main body 1)
In the space 4 in the hinge unit 20), a blower fan 37 is arranged in a state attached to the shoulder member 7. The blower fan 37 is a centrifugal fan having a scroll type fan casing.

The outlet 37a of the blower fan 37 has
A duct 38 is connected, and the upper end of the duct 38
It faces an inlet 39 a of an annular passage 39 formed in the shoulder member 7. The shoulder member 7 has a plurality of communication ports 40 communicating the annular passage 39 with an upper portion of an annular gap C formed between the rice cooker 3 and the protection frame 6. . That is, the air from the air blowing fan 37 is supplied to the upper portion of the gap C through the duct 38, the annular passage 39, and the communication port 40. Reference numeral 41 denotes an air intake formed in the lower part of the body 5a of the outer case 5.

The side opposite to the hinge of the rice cooker main body 1 (that is, the side on which the lock mechanism 42 for locking the lid 2 is provided).
Is provided with a control board 43 in which a control unit for controlling the energization of the work coil 10, the heat retaining heater 13, the shoulder heater 31 and the like is incorporated, while the hinge member ( That is, on the side where the lock mechanism 42 for locking the lid 2 is provided, various switches (for example, a rice cooker switch, a reservation switch, a warming switch, etc.) and an operation panel unit 44 having a liquid crystal display device are provided. Have been.

As shown in FIG. 2, the operation panel section 44 includes a rice cooker switch 45, a reservation switch 46, a heat insulation selection switch 47 for selecting and setting normal heat insulation and low temperature insulation, a cancel switch 48, a reheat switch 49, A menu switch 50, an hour switch 51 for time adjustment, a minute switch 52 for time adjustment, and a liquid crystal display 53 are provided. Next, an electric configuration of the electric rice cooker according to the present embodiment will be described based on an electric circuit diagram shown in FIG. Parts corresponding to those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

The electric power from the commercial AC power supply 54 is supplied to the work coil 10 via the temperature fuse 55 and the rectifier circuit 56 which detect and melt the abnormal heating of the rice cooker 3 and are supplied to the heat retaining heater 13 and the shoulder heater 31. Will also be supplied. Reference numeral 57 denotes a smoothing capacitor, and 58 denotes a resonance capacitor.

The work coil 10 is turned on / off by a command from a microcomputer unit (hereinafter abbreviated as a microcomputer) 59 through a main heater drive circuit 60.
A control signal from a power transistor 61 to be FF controlled is to be supplied.

The warming heater 13 and the shoulder heater 31 are supplied to the microcomputer 59 with instructions from the microcomputer 59 via the warming heater driving circuit 62 and the shoulder heater driving circuit 63, respectively.
Control signals are supplied from transistors 64 and 65 that are N / OFF controlled.

The microcomputer 59 includes a power transistor 69 and a transistor 6 according to a predetermined program.
4, 65, thereby controlling the work coil 10,
The energization to the warming heater 13 and the shoulder heater 31 is controlled. This energization control is performed based on an output signal output from a thermistor 66 incorporated in the center sensor 8 via a temperature sensor detection circuit 67. Reference numeral 68 denotes a pan detection switch for detecting the presence or absence of the rice cooker 3, and a signal from the pan detection switch 68 is input to the microcomputer 59 via a pan detection circuit 69. Code 7
0 is a notification buzzer for notifying the completion of rice,
The notification buzzer 70 is driven and controlled by a buzzer driving circuit 71 to which a control signal from the microcomputer 59 has been input.

Next, the rice cooking control in the electric rice cooker according to the present embodiment will be described with reference to the flowchart shown in FIG.

When rice cooking is started, a water absorption step is executed in step S1, and when the water absorption step is completed, the work coil 10 is operated at full power (ie, 100% output) in step S2. At this time, the heat retention heater 13 and the shoulder heater 31 may be energized.

Then, in step S3, the rice cooker temperature T detected by the center sensor 8 is input, and in step S4, the rice cooker temperature T is raised to the boiling temperature (for example, 100%).
° C), it is determined in step S5 that t
The count of the a timer is started, and the number of times that the rice cooker temperature T exceeds 100 ° C. in step S6 (that is,
X), and the output of the work coil 10 is reduced to half in step S7. Although the temperature of the rice cooker T decreases due to the decrease in the output of the work coil 10,
When the rice cooker temperature T falls below 99 ° C. in step S8, the process returns to step S2 and the output of the work coil 10 becomes
00%, and then the above-described control is executed.
If it is determined in step S8 that T ≧ 99 ° C., it is determined whether or not the ta timer has counted up in step S9. Until the determination is affirmative, the process returns to step S7 and the work coil 10 Output is 1
/ 2 is maintained.

That is, after the work coil 10 reaches the boiling point due to the 100% output, the temperature rise and the temperature drop which occur when the output of the work coil 10 is controlled to maintain the rice cooker temperature T at the boiling point are caused. That is, the number of mountains (ie, rice cooked at 100 ° C. detection count X) is to be detected within a predetermined time ta. Since the count X is proportional to the amount of rice (ie, the total number) as shown in FIGS.
As shown in the figure, the count X is divided into three kinds of threshold values A,
The total number can be determined by performing the determination based on B and C. The number of valleys or the number of peaks and valleys may be counted.

Next, steps S10 to S12
In step S10, the count X is compared with the threshold values A to C. If it is determined in step S10 that 0 ≦ X ≦ A, the output of the work coil 10 is reduced to に お い て in step S13, and A ≦ A in step S11. If it is determined that X ≦ B, the output of the work coil 10 is set to 5/8 in step S14. If it is determined that B ≦ X ≦ C in step S12, the output of the work coil 10 is set to 3 in step S15. / 4 and step S
If it is determined in step 12 that C <X, step S1 is executed.
In 6, the output of the work coil 10 is set to full power (that is, 100%), and the cooking process is executed in step S17. That is, energization control of the work coil 10 after boiling is performed according to the total number.

As described above, in the present embodiment, the work coil 10 is operated at full power and cooked at a burst with high heat from the end of water absorption to boiling, and thereafter the amount of rice (ie, (Combination number). Therefore, delicious rice can be cooked in a short time.

By the way, in the conventional rice cooking, the time from the start of the steaming step after the completion of the cooking step to the completion of the rice cooking is displayed on the liquid crystal display 53, so that the rice cooking is started when the rice cooking is started. There was the inconvenience of not knowing the time to go up. Therefore, in the present embodiment, the remaining time from the start of rice cooking until the rice is cooked is displayed on the liquid crystal display unit 53.

The remaining rice cooking time display control will be described with reference to the flowchart shown in FIG.

In step S1, the menu switch 5
When the rice cooking menu is selected by 0 and rice cooking is started by turning on the rice cooking switch 45 in step S2, a standard remaining time set in advance corresponding to the selected rice cooking menu is displayed. Thereafter, when the total number is determined in step S4, the remaining time is displayed according to the total number in step S5. When the cooking is completed in step S6, the remaining time is displayed again (in other words, the steaming time is displayed). ) Is made. And step S
If it is determined in step 8 that the steaming has been completed, the notification buzzer 70 is sounded in step S9, and then the process proceeds to a warming step in step S10.

In this way, the remaining time is displayed for each rice cooking process, which is very convenient for the user.

The notification of the completion of cooking by the notification buzzer 70 is conventionally performed eight times, but the following is convenient.

That is, four transistors 72A to 72D for controlling the notification buzzer 70 are provided.
When the transistor 72B is turned on, the notification buzzer 70 emits a small sound twice.
When the transistor 72C is turned on, the notification buzzer 70 sounds twice with a medium sound, and when the transistor 72D is turned on, the notification buzzer 70 sounds twice with a loud sound. . That is, the sound of the buzzer 70 is gradually increased in four stages. In this way, the cooked food is clearly understood. The notification buzzer 7
When any switch is pressed during the sounding of 0, the buzzer notification is canceled.

Second Embodiment FIG. 9 is a characteristic diagram for explaining the determination of the total number in an electric rice cooker according to a second embodiment of the present invention.

In this case, the total number is determined in the water absorption step, but a predetermined time tb (for example, 5 minutes) from the start of water absorption.
Until the time tc (for example, 10 minutes) elapses after the elapse of the temperature, the temperature rise and the temperature drop that occur when the energization of the work coil 10 is controlled so as to maintain the rice cooker temperature T at the water absorption temperature Ta. The total number is determined by detecting the number of peaks (i.e., the water absorption temperature detection frequency count Y) generated by the repetition of the above. The number of valleys or the number of peaks and valleys may be counted. In this case, since the work coil 10 can be operated at full power from the end of the water absorption process to the completion of cooking, rice can be cooked in a shorter time. Other configurations and effects are
The description is omitted because it is the same as in the first embodiment.

The above-described heating control can of course be applied to cooking rice porridge.

In each of the above embodiments, the work coil is used as the heating means for cooking rice.
Needless to say, the present invention can be applied to a device using an electric heater as the heating means for cooking rice.

[0051]

According to the first aspect of the present invention, the rice cooker body for removably storing the rice cooker, heating means for heating the rice cooker, the lid of the rice cooker main body, A temperature detecting means for detecting a temperature, wherein the electric rice cooker is configured to control the power supply to the heating means in the water absorption step, the cooking step and the steaming step, wherein the temperature detection means detects the temperature after the water absorption step is completed. In the cooking step during which the temperature of the cooked rice rises to or near the boiling point, the heating means is controlled at the maximum heating amount, and after reaching the boiling point or near the boiling point, the rice in the rice cooker is controlled. Heating control means for controlling the amount of heating by the heating means in accordance with the amount of water, and during the period from the end of water absorption to boiling, the heating means is controlled to be heated at the maximum heating amount and cooks at a high heat at once. Is Then the amount of rice (i.e., the number of case) since to be heated by the heating amount in accordance with, there is an effect that it is possible to increase cooking in a short time delicious rice.

As in the invention of claim 2, claim 1
In the electric rice cooker described above, the determination of the amount of rice in the rice cooker is performed while the heating control unit controls the heating at the boiling point or near the boiling point after heating the heating unit at the maximum heating amount. In this case, the determination of the amount of rice (that is, the determination of the total number) does not adversely affect the amount of heating during cooking.

As in the invention of claim 3, claim 1
In the electric rice cooker described above, when the determination of the amount of rice in the rice cooker is performed in the water absorption step, the determination of the amount of rice (that is, the total number) is determined by the amount of heating at the time of cooking. No adverse effects.

As in the invention of claim 4, claim 2
In the electric rice cooker described above, the temperature detected by the temperature detecting means is maintained at the boiling point while the heating control means controls the heating at or near the boiling point after heating the heating means at the maximum heating amount. The number of peaks and / or valleys generated by the repetition of the temperature rise and the temperature drop that occur when controlling the energization of the heating means so as to cause the rice within the rice cooker to be detected within a predetermined time. When the amount is determined, it is possible to easily determine the amount of rice (that is, determine the total number).

As in the invention of claim 5, claim 3
In the electric rice cooker described above, in the water absorption step, a peak caused by repetition of a temperature rise and a temperature fall that occurs when controlling the power supply to the heating means so as to maintain the temperature detected by the temperature detection means at the water absorption temperature. Alternatively, when the number of valleys is detected within a predetermined time to determine the amount of rice in the rice cooker, the determination of the amount of rice (that is, the total number determination) can be easily performed. It can be carried out.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric rice cooker according to a first embodiment of the present invention.

FIG. 2 is a front view of an operation panel unit in the electric rice cooker according to the first embodiment of the present invention.

FIG. 3 is a connection diagram of a control circuit unit in the electric rice cooker according to the first embodiment of the present invention.

FIG. 4 is a flowchart of heating control in the electric rice cooker according to the first embodiment of the present invention.

FIG. 5 is a time chart for explaining the total number determination in the electric rice cooker according to the first embodiment of the present invention.

FIG. 6 is a characteristic diagram showing threshold values at the time of determining the total number in the electric rice cooker according to the first embodiment of the present invention.

FIG. 7 is a flowchart of the remaining rice cooking time display in the electric rice cooker according to the first embodiment of the present invention.

FIG. 8 is a circuit diagram showing another example of the notification buzzer control in the electric rice cooker according to the first embodiment of the present invention.

FIG. 9 is a time chart for controlling the total number judgment in the electric rice cooker according to the second embodiment of the present invention.

[Explanation of symbols]

1 is a rice cooker main body, 2 is a lid, 3 is a rice cooker, 8 is a temperature detecting means (center sensor), 10 is a heating means (work coil), 13 is a warming heater, 31 is a shoulder heater, 43 is a control board, 59 is a heating control means (microcomputer unit).

Claims (5)

[Claims] 1. A rice cooker main body for removably storing a rice cooker, heating means for heating the rice cooker, a lid of the rice cooker main body, and temperature detecting means for detecting a temperature of the rice cooker. An electric rice cooker comprising: an electric rice cooker configured to control energization of the heating means in a water absorption step, a cooking step, and a steaming step, wherein a temperature of the rice cooker detected by the temperature detection means after the water absorption step is a boiling point. Or, in the cooking step during the rise to near the boiling point, the heating means controls the heating at the maximum heating amount, and after reaching the boiling point or near the boiling point, the heating is performed according to the amount of rice in the rice cooker. An electric rice cooker provided with a heating control means for controlling a heating amount by the means. 2. The determination of the amount of rice in the rice cooker is performed while the heating control means controls the heating at or near the boiling point after heating the heating means at the maximum heating amount. The electric rice cooker according to claim 1, wherein: 3. The electric rice cooker according to claim 1, wherein the determination of the amount of rice in the rice cooker is performed in the water absorption step. 4. The method according to claim 1, wherein the heating control means controls the temperature detected by the temperature detecting means at the boiling point while controlling the heating means at the boiling point or near the boiling point after heating the heating means at the maximum heating amount. The amount of rice in the rice cooker is detected by detecting the number of peaks and / or valleys caused by the repetition of temperature rise and temperature fall that occur when controlling the power supply to the heating means within a predetermined time. The electric rice cooker according to claim 2, wherein the determination is made. 5. A peak or a peak caused by repetition of a temperature rise and a temperature drop that occur when controlling the energization of the heating means so as to maintain the temperature detected by the temperature detection means at the water absorption temperature in the water absorption step. 4. The electric rice cooker according to claim 3, wherein the amount of rice in the rice cooker is determined by detecting the number of valleys within a predetermined time.