JP2000296059A - Jar rice cooker - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a jar rice cooker capable of immediately detecting the absence of a pan when the pan is taken out. SOLUTION: A lid opening / closing detecting means 39 for detecting the open / closed state of the lid, a no-pan detecting means 48 for detecting the presence / absence of a pan, and a heating coil 3 for heating the pan are provided. The panless detecting means 48 is operated accordingly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jar rice cooker used for general household or business use.

[0002]

2. Description of the Related Art Conventionally, this type of jar rice cooker has a configuration as shown in FIG. 6, for example. 1 in the figure
Is a rice cooker main body having an open upper surface, in which a pot 2 for putting rice and water is detachably stored. Inside the rice cooker main body 1, a heating coil 3 serving as a pot heating means for heating the bottom of the pot 2 is provided at the bottom of the pot, and a side heating means 4 for heating the side of the pot is provided at the waist portion of the pot. It is arranged. At the center of the heating coil 3, a pot sensor 5 for detecting the temperature of the pot 2 is provided. Reference numeral 6 denotes a lid that covers the top opening of the rice cooker so as to be openable and closable. The lid 6 is rotatably supported via a pin 9 on a hinge member 8 integrally formed on the upper part of the upper frame 7. A radiator plate 10 is fixed to the lid 6, and a lid sensor 11 for detecting the temperature in the pot 2 and a lid heating means 12 for heating the lid are attached to the radiator plate 10 with aluminum tape.

[0003] Reference numeral 13 denotes a control board, which is based on a sequence of rice cooking and heat preservation stored in a microcomputer, and based on the energization state of the heating coil 3, the side heating means 4, the lid heating means 12, the pan sensor 5 and the lid sensor 11. And the signal of the operation display unit 14 are input / output controlled.

Reference numeral 15 denotes a heating board on which an inverter circuit for supplying a high-frequency current to the heating coil 3 is mounted. The inverter circuit supplies a high-frequency current to the heating coil 3 based on a signal from the control board 13 to heat the pot 2.

In the case of such a rice cooker using a heating means for heating a pan by supplying a high-frequency current to a heating coil by an inverter circuit, means for detecting whether or not the pan 2 is housed in the main body 1 is as follows. Without using mechanical switches,
A method is used in which the inverter circuit 15 is actually driven to supply a high-frequency current to the heating coil 3 and the input current to the rice cooker main body 1 at that time is detected to detect whether or not the pan 2 is present. .

[0006]

However, in such a jar rice cooker, in order to detect the presence or absence of the pot 2, it is necessary for the inverter circuit 15 to energize the heating coil 3 to actually heat the pot 2. However, according to the sequence stored in the microcomputer during cooking and keeping warm, for example, in the warming step, when the temperature of the pot sensor 5 is 71 ° C. or less, the heating coil 3 is energized to heat the pot 2 and the pot is heated to 71 ° C. or more. Then, the power supply to the heating coil 3 is stopped to stop the heating.
Also, energization is forcibly prohibited for a certain period of time, as in the rice drying process during cooking.

When the pan 2 is taken out under such a condition that the heating coil 3 is not energized in the sequence, the panless detection circuit cannot immediately detect the panless state, and then the heating coil 3 is energized. Until then, the operation continues as if there is a pot.

Further, since no power is supplied to the heating coil 3 in the standby state or during timer reservation, the presence / absence of the pan cannot be detected. There is no other way but to energize.

As described above, in the method of electrically detecting the presence or absence of a pan by driving the inverter circuit to energize the heating coil, the absence of the pan cannot be detected immediately after taking the pan, There was a problem that useless power supply was required to detect the absence.

It is a first object of the present invention to solve the above-mentioned problem, and to provide a jar rice cooker which can immediately detect absence of a pot when the pot is taken out.

A second object of the present invention is to provide a jar rice cooker which can detect the absence of a pot without wasteful energization when the pot is taken out.

[0012]

In order to achieve the first object, the present invention provides a main body, a lid for covering an upper part of the main body, a lid open / close detecting means for detecting an open / closed state of the lid, A pan removably housed in the main body, a pan-less detection means for detecting the presence or absence of the pan, a pan heating means for heating the pan, and a control means for driving and controlling the pan heating means, The control means operates the pan-less detection means in accordance with opening and closing of the lid.

In order to achieve the second object, the present invention is characterized in that when the control means detects that the lid is closed after the lid is opened, the control means operates the panless detection means. is there.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 comprises a main body,
A cover that covers an upper portion of the main body, a lid open / close detection unit that detects an open / closed state of the lid, a pan that is detachably stored in the main body, a pan-less detection unit that detects the presence or absence of the pan, A pan heating means for heating the pan, and a control means for driving and controlling the pan heating means, wherein the control means operates the pan-less detection means in response to opening and closing of a lid to remove the pan. Each time the lid is opened and closed, the panless detection circuit operates, so that when the pan is taken out, the absence of the pan can be detected immediately.

According to a second aspect of the present invention, the lid is opened by operating the panless detecting means at least until the control means detects that the lid is opened and then detects that the lid is closed. When the pan is taken out while it is running, the absence of the pan can be detected immediately.

According to a third aspect of the present invention, when the control means detects that the lid has been closed after the lid has been opened, the control means activates the pan-less detection means, so that the pan is opened while the lid is open. Since the absence detection means is not operated, there is no need to uselessly supply electricity, and the absence of the pan can be detected when the pan is taken out and the lid is closed.

According to the fourth aspect of the present invention, since the no-pan detecting means is configured to detect the presence or absence of the pan by operating the pan heating means, no mechanical parts are required. Can be used to detect panlessness.

[0018]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. As shown in the block diagram of FIG. 1, the pot 31 contains rice and water, and the inverter 3
Heating is performed by a heating coil 3 that is energized by 2 and a side surface heating unit 34 that heats the side surface. 35 is a pot 31
The heat radiating plate 35 is provided with a lid heating means 36 for heating the lid, and a lid sensor 37 for detecting the temperature of the lid. Numeral 38 denotes a pan sensor for detecting the temperature at the bottom of the pan 31. The lid opening / closing detecting means 39 detects the open / closed state of the lid covering the upper surface of the pot 31.

Reference numeral 40 denotes an AC power supply, which supplies power to the inverter 32 via input current detection means 41. The input current detecting means 41 receives an input current from the AC power supply 40 and outputs a voltage signal proportional to the current value.

The control means 42 receives the output of the pot sensor 38 and the output of the lid sensor 37, and determines the amount of rice and water in the pot 31, that is, the amount of cooked rice. The heating output of the heating coil 3, the side heating means 34, and the lid heating means 36 is determined by the output of 43, and the output of the pan sensor 38 and the output of the lid sensor 37 are input and based on the rice cooking sequence stored in the storage means 44. Display means 4 for controlling the heating output of the heating coil 3, the side heating means 34 and the lid heating means 36 and further displaying the state of the rice cooker.
5 and a notifying means 46 for notifying an abnormality of the rice cooker, a rice cooking control means 47 for outputting a signal, a storage means 44 for storing a rice cooking sequence, and an output voltage signal from an input current detecting means 41. And a panless detecting means 48 for determining the presence or absence of a pan based on the signal level. The operation unit 49 outputs a signal for selecting a rice cooking sequence stored in the storage unit 44 or starting rice cooking to the storage unit 44.

Here, the operation of the panless detecting means 48 will be briefly described. When the control means 42 drives the inverter 32 to energize the heating coil 3, the pan 31 is placed at a predetermined position in the main body. In case of rice cooking, about 12
00W (about 12A for input current) About 500W in case of heat insulation
(About 5 A in the input current). On the other hand, when the pot 31 is removed, when the inverter 32 is driven under the same conditions and the heating coil 3 is energized, only about 50 W (about 0.5 A in input current) is output. Therefore, the panless detecting means 48 inputs the voltage proportional to this input current from the input current detecting means 41, so that the input voltage becomes 1A.
It is determined that there is a pot when the temperature is equal to or more than 1A, and that there is no pot when the value is 1A or less.

A specific example of this rice cooker is shown in FIGS.
In FIG. 2, reference numeral 50 denotes a rice cooker main body having an open upper surface, in which a pot 31 for putting rice and water is detachably stored. Inside the main body 50, a heating coil 3 for heating the pan 31 and an inverter 32 for energizing the heating coil 3
And an inverter board 51 equipped with input current detecting means 41 for converting an input current from the AC power supply 40 into a voltage signal.
And a side heating means 34 for heating the side of the pan 31 are provided. A pan sensor 38 for detecting the temperature of the pan 31 is provided at the center of the heating coil 3. Reference numeral 52 denotes a lid which covers the upper opening of the rice cooker main body 50 so as to be freely opened and closed.
Is rotatably supported via a pin 55. Lid 52
A radiator plate 35 is fixed to the radiator plate 35. A lid heating means 36 for heating the lid and a lid sensor 37 for detecting the temperature of the radiator plate 35 are attached to the radiator plate 35 so as to be in close contact with each other. Further, a control board 56 is provided in the lid 52. The control board 56 has a microcomputer 57 as control means, an LCD 58 as display means, a buzzer 59 as notification means, and operation means 49 mounted thereon. Further, inside the lid 52, a lid opening / closing detecting means 39 including a float 60 and a float detection 61 is provided.

The microcomputer 57 receives the output of the pot sensor 38 and the output of the lid sensor 37, and determines the amount of rice and water in the pot 31, that is, the amount of cooked rice. The heating output of the heating coil 3, the side heating means 34 and the lid heating means 36 is determined by the output of 43, the output of the pan sensor 38 and the output of the lid sensor 37 are input, and the inverter 32 is driven based on the rice cooking sequence to heat. Rice cooking control for controlling the heating output of the coil 3 and the heating output of the side heating means 34 and the lid heating means 36, and further outputting signals to an LCD 58 for displaying the state of the rice cooker and a buzzer 59 for notifying an abnormality of the rice cooker. Means 47, a storage means 44 for storing a rice cooking sequence, and an output voltage signal from the input current detecting means 41, and the presence or absence of a pot is determined based on the voltage signal level. Constitute a no pot detection means 48. The operating means 49 outputs a signal for selecting a rice cooking sequence stored in the storage means 44 in the microcomputer 57 and for starting rice cooking to the microcomputer 57.

FIG. 3 is an enlarged view of the lid opening / closing detecting means 39. The float 60 is a spherical magnet, and the float detection 61 is a reed switch that opens and closes a contact by the magnetism of the float 60. Since the float 60 rides on the inclined groove 62, the float 60 moves to the float detection 61 side when the lid 52 is closed, and the float 60 is opposite to the float detection 61 when the lid 52 is open. Move to the side. The movement of the float 60 changes the influence of magnetism on the float detection 61, so that the float detection 61
This opens and closes the contacts, enabling the detection of the opening and closing of the lid.

Another method is to dispose a magnet on one of the main body 50 and the lid 52 and a reed switch on the other to detect opening and closing of the lid 52.

In the above configuration, the operation of the jar rice cooker of the present invention when keeping warm will be described with reference to FIG. FIG. 4 is a heat retention sequence diagram when the rice is kept warm in the jar rice cooker according to the embodiment of the present invention. The sequence during the heat retention, the detected temperatures of the pot sensor 38 and the lid sensor 37,
The input power to the heating coil 3, the side surface heating means 34, and the lid heating means 36 is shown.

The microcomputer 57 includes the operating means 4
9 and the lid sensor 3 based on the sequence of rice cooking and heat preservation stored in the storage means 44 in the microcomputer 57 in advance.
7 and the output signal from the lid opening / closing detecting means 39 are used as input signals to control heating of the jar rice cooker.

In the case of keeping the cooked rice warm, the temperature of the rice immediately after the cooking is about 100 ° C., but the normal temperature is about 71 ° C. Keep the temperature stable during warming. In order to optimally control the temperature of the rice during the heat retention, different steps of the heating amount are provided according to the temperature of the rice. In this state, the temperature of the rice and the temperature of the pan 31 are substantially the same, and the temperature of the rice can be controlled by the temperature detected by the pan sensor 38.

The microcomputer 57 uses the heating coil 3 and the side heating means 34 to lower the temperature as quickly as possible until the temperature detected by the pan sensor 37 reaches 71 ° C. in the temperature keeping step after the rice cooking (T0). The power supply to the lid heating means 36 is stopped, and the heating is stopped. Then, when the temperature detected by the pan sensor 38 becomes 71 ° C. or lower (T1), the process proceeds to the temperature keeping temperature adjusting step.

In the temperature control step, when the temperature detected by the pan sensor 38 is 71 ° C. or lower, the power supply to the heating coil 3 is turned on (1).
When the temperature detected by the pot sensor 38 becomes 71 ° C. or more again, the power supply to the heating coil 3 is stopped, the heating is stopped, and the lid sensor 37 is turned on.
When the detected temperature is 72 ° C. or less, the side heating means 34 and the lid heating means 36 are energized at an energization rate of (2 seconds ON / 16 seconds cycle) and heated, and the detected temperature of the lid sensor 37 becomes 7 again.
When the temperature reaches 2 ° C. or more, the side heating means 34 and the lid heating means 36
The current is stopped, and the heating is stopped, and this operation is repeated. By this operation, it is possible to maintain the temperature of the rice at a stable temperature during the heat retention. If the energization rates of the heating coil 3, the side heating means 34 and the lid heating means 36 are above the above, only the surroundings of the heating means are rapidly heated, so that the temperature around the pot sensor 38 and the lid sensor 37 becomes a constant value. Even in the above case, the heat is not transmitted to the central portion of the rice in the pot 31, so that the temperature is low and the temperature of the rice is uneven.
Therefore, the temperature of the rice and the atmosphere in the pot 31 are maintained at a constant temperature by the heat-retaining heating operation with the energization ratio lowered as described above.

The operation when the pot 31 is taken out during the heat keeping lowering step will be described with reference to FIG. In FIG. 5, T
Open the lid 52 at the timing of 2, and at the timing of T3, set the pot 3
1 is taken out and the lid is closed at the timing of T4,
When the pan 31 is taken out in step 3, the temperature detected by the pan sensor 38 sharply drops and drops to 71 ° C. or less at the timing of T5. In such a case, it took at least about 20 minutes from the removal of the pot 31 at T3 to the start of energization of the heating coil 3 at T5.

However, in the embodiment of the present invention, when the lid 52 is opened at the timing of T2, the microcomputer 5
The lid opening / closing detecting means 39 in 7 detects that the lid 52 is opened, and outputs a signal to the rice cooking control means 47. Receiving this signal, the rice cooking control means 47 drives the inverter 32 at a constant duty cycle (1 second ON / 60 second cycle) to energize the heating coil 3. This energizing operation is continued until the lid 52 is closed at the timing of T4 and the lid opening / closing detecting means 39 detects that the lid 52 is closed and outputs a signal.

Therefore, when the pan 31 is taken out at the timing of T3, the heating coil 3 is energized at least within a predetermined period (60 seconds), and the input current detecting means 41 detects an input current into the main body and outputs the current. A voltage signal proportional to the value is output to the panless detecting means 48, and the panless detecting means 48
It is determined that 1 does not exist.

As described above, according to the present embodiment, when the lid 52 is opened and closed to take out the pot 31 while keeping the rice warm, the microcomputer 57 keeps the heating coil 3 constant while the lid 52 is open. Since the power is supplied periodically and the pan-less detecting means 48 is operated, it is possible to immediately detect the absence of the pan 31 when the pan 31 is taken out.

Embodiment 2 Hereinafter, a second embodiment of the present invention will be described with reference to FIG. 6. However, since the configuration is the same as that of the first embodiment, only different operations will be described. Example 1
Then, when the lid 52 is opened at the timing of T2, the lid open / close detecting means 39 in the microcomputer 57 detects that the lid 52 is opened, outputs a signal to the rice cooking control means 47, and the rice cooking control means 47 Upon receiving this signal, the inverter 32 is driven at a constant duty cycle (1 second ON / 60 second cycle) to energize the heating coil 3. This energizing operation is continued until the lid 52 is closed at the timing of T4 and the lid opening / closing detecting means 39 detects that the lid 52 is closed and outputs a signal. In the present embodiment, the rice cooking control means 47 is used. Is T
The lid 52 is opened at the timing of 2 and the lid opening / closing detecting means 3
9 detects that the lid 52 has been opened, and then the lid 52 is closed at the timing of T4, and the lid opening / closing detecting means 39 detects that the lid 52 has been closed, outputs a signal, and when the signal is received, the signal is fixed. The inverter 32 is driven for a period of time (about one second) to energize the heating coil 3.

Therefore, when the pan 31 is taken out at the timing of T3, at the timing of T4 when the lid 52 is closed, the heating coil 3 is energized, the input current detecting means 41 detects the input current into the main body, and the current value is detected. Is output to the panless detecting means 48, and the panless detecting means 48
It is determined that 1 does not exist.

As described above, according to this embodiment, when the lid 52 is opened and closed in order to take out the pot 31 while keeping the rice warm, the microcomputer 57 switches the heating coil 3 when the lid 52 is closed. Since the power is supplied for a certain period of time and the pan-less detecting means 48 is operated, after the pan 31 is taken out,
Pot 31 when there is a person who is using it without performing useless electricity
Can be detected.

(Embodiment 3) Hereinafter, the third embodiment of the present invention has the same configuration as that of the first embodiment, and therefore only different operations will be described. In the first embodiment, the case where the lid 52 is opened and closed during the heat retention is described. However, when the lid 52 is opened during the standby or the timer reservation, the lid open / close detection means 39 in the microcomputer 57 causes the lid 52 to be opened. Detect that it has opened,
Next, the lid 52 is closed, and the lid opening / closing detecting means 39 detects that the lid 52 is closed and outputs a signal. When the signal is received, the inverter 32 is driven for a certain time (about 1 second), and the heating coil 3 is turned on. Turn on electricity.

As described above, according to the present embodiment, when the lid 52 is opened and closed in order to take out the pot 31 during standby or timer reservation, the microcomputer 57 sets the heating coil when the lid 52 is closed. 3 is energized for a certain period of time to activate the pan-less detection means 48, so that it is possible to detect that there is no pan 31 when there is a person using the power without wasteful energization after the pan 31 is taken out. Can be done.

[0040]

As described above, the first aspect of the present invention provides
A main body, a lid covering an upper part of the main body, a lid open / close detecting means for detecting an open / closed state of the lid, a pan removably stored in the main body, and a pan-less detecting means for detecting the presence or absence of the pan And a pan heating means for heating the pan, and a control means for driving and controlling the pan heating means, wherein the control means operates the pan-less detection means in accordance with opening and closing of a lid, so that the pan is Each time the lid is opened and closed to take out, the potless detection circuit operates each time, so it is not limited to heating the pot while cooking or keeping warm, it heats like waiting or timer reservation Even when there is no pot, the absence of the pot can be immediately detected when the pot is taken out.

Further, the invention according to claim 2 is characterized in that the control means operates the pot-less detection means at least until it detects that the lid has been opened and then detects that it has been closed. It is not limited to the state where the pot is heated during warming or warming, and even when the heating is not performed such as during standby or timer reservation, it is possible to detect the absence of the pot as soon as the lid is opened and the pot is taken out .

According to a third aspect of the present invention, when the control means detects that the lid has been closed after the lid has been opened, the control means activates the pan-less detection means to thereby prevent the pan from being opened. Does not operate the panless detection means, so there is no need to uselessly supply electricity, and it is not limited to the state of heating the pot while cooking or keeping warm, and the state where heating is not performed such as during standby or timer reservation In the above, when the pan is taken out and the lid is closed, the absence of the pan can be detected.

Further, the invention according to claim 4 has a configuration in which the pot-less detecting means operates the pot heating means to detect the presence or absence of the pot, so that no mechanical parts are required, so that the apparatus is simple. With the configuration, it is possible to realize panless detection.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a jar rice cooker according to a first embodiment of the present invention.

FIG. 2 is a fragmentary sectional view of the same jar rice cooker.

FIG. 3 is an enlarged cross-sectional view of the lid opening / closing detecting means of the rice cooker;

FIG. 4 is a diagram showing a heat retention sequence of the jar rice cooker.

FIG. 5 is an operation diagram of the same jar rice cooker at the time of taking a pot;

FIG. 6 is an operation diagram of a jar rice cooker according to a second embodiment of the present invention at the time of taking a pot;

FIG. 7 is a fragmentary sectional view of a conventional jar rice cooker.

[Explanation of symbols]

 Reference Signs List 3 heating coil 31 pot 33 pot heating means 34 side heating means 35 heat sink 36 lid heating means 37 lid sensor 38 pan sensor 39 lid open / close detecting means 42 control means 47 rice cooking control means 50 main body 52 lid 57 microcomputer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Makoto Katakasu 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 4B055 AA05 BA22 CA01 CA09 CA22 CA64 CA71 CA81 CC04 CC16 CC17 CC40 CD01 CD31 CD41 DA02 DA03 DB14 GA04 GB01 GB32 GB33 GC12 GC38

Claims (4)

[Claims] 1. A main body, a lid covering an upper part of the main body, a lid open / close detecting means for detecting an open / closed state of the lid, a pan detachably stored in the main body, and detecting presence / absence of the pan. No-pan detection means to do, pan heating means to heat the pan,
A jar rice cooker comprising: a control unit for controlling the driving of the pan heating unit, wherein the control unit operates the pan-less detection unit in response to opening and closing of a lid. 2. The jar rice cooker according to claim 1, wherein the control means operates the no-pan detection means at least from when the lid is opened to when the lid is closed. 3. The jar rice cooker according to claim 1, wherein the control means activates the no-pan detection means when detecting that the lid is closed after the lid is opened. 4. The jar rice cooker according to any one of claims 1 to 3, wherein said pot-less detecting means is configured to operate a pot heating means to detect the presence or absence of a pot.