JPH06260271A - Electromagnetic cooker - Google Patents

Abstract

PURPOSE:To detect the boiling of a cooking material at high precision by detecting the inclinations of temperature change at heating start, middle time, and any time by a temperature detecting element provided on a cooking vessel receiver and an arithmetic means, and judging the boiling start time. CONSTITUTION:When a user operates a start input means 6, an automatic boiling detecting means 7 is reset, and a coil current control means 4 is set to a maximum heating output, and driven. When a high frequency current is supplied to an induction heating coil 3 to start the rise of temperature of a cooking vessel 1, a temperature detecting element 5 detects this temperature. The inclinations of temperature change at heating start and middle time are detected by first and second inclination detecting means 11, 12, and an inclination forming the standard of boiling detection is calculated from the output by an inclination arithmetic means 13. The output of a third inclination detecting means 14 for detecting the inclination of the detected temperature at any time and the output of the means 13 are compared to each other by a boiling judging means 15, whereby the boiling start time can be judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic cooker capable of automatically detecting boiling of cooked food.

[0002]

2. Description of the Related Art The structure of a conventional electromagnetic cooker with an automatic boiling detection function will be described with reference to FIG. Reference numeral 101 denotes a cooking container placed on a cooking container receiver 102 made of a ceramic plate, which is induction-heated by a high-frequency magnetic field generated by an induction heating coil 103 provided under the cooking container receiver 102. 104 is an induction heating coil 103
Coil current control means for supplying a high frequency current to the high frequency inverter circuit 104a and the high frequency inverter output control circuit 104b. Reference numeral 105 denotes a temperature sensor attached to the lower surface of the cooking container receiver 102, which indirectly detects the temperature of the cooking container 101 by detecting the temperature of the cooking container receiver 102. The output of the temperature detecting element 105 is an automatic boiling detecting means 106 for automatically detecting the start of boiling.
Have been transmitted to. Further, 107 is a start input means composed of a switch for the user to instruct the start of operation, and this signal is similarly transmitted to the automatic boiling detection means 106. The first inclination detecting means 108 constituting the automatic boiling detecting means 106 receives the output of the temperature detecting element 105, and
As shown in ( ₁₎ , the slope of the average temperature rise from the _first predetermined temperature T ₁ to the second predetermined temperature T ₂ is detected. In other words, the time required to pass these two temperatures is measured to detect the average temperature rise slope. The tilt calculating means 109 calculates 1/3 of the tilt detected by the first tilt detecting means 108. This 1/3 is an empirically determined value. The second inclination detecting means 110 receives the detected temperature signal of the temperature detecting element 105 and detects the differential value, that is, the inclination, at any time. The boiling determination means 111 which is the output of the automatic boiling detection means 106 is the second inclination detection means 11
By comparing the output of 0 and the output of the inclination calculating means 109, when the output of the second inclination detecting means 110 becomes smaller than the output of the inclination calculating means 109, the food in the cooking container 101 boils. To judge. That is, the output of the coil current control means 104 is stopped at this point, and the supply of the high frequency current to the induction heating coil 103 is stopped.

[0003]

The above-described conventional electromagnetic cooker has a problem that the setting of the boiling detection timing is not very accurate. That is, the inclination of the temperature rise detected by the first inclination detection means becomes unstable because the shape of the cooking container 101, especially the shape of the bottom surface, may not be in close contact with the cooking container receiver 102. There is. For this reason, the boiling detection timing may be earlier or later.

The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide an electromagnetic cooker capable of detecting boiling with high accuracy.

[0005]

[Means for Solving the Problems] A first means of the present invention for achieving the above object is to provide a cooking container receiver for receiving a cooking container, and induction heating for generating a high frequency magnetic field arranged on the lower surface of the cooking container receiver. A coil, a temperature detecting element for detecting the temperature provided in the cooking container receiver, a first inclination detecting means for detecting an inclination of the temperature change at the start of heating by receiving the output of the temperature detecting element, and this temperature Second inclination detecting means for detecting the inclination of the temperature change during the heating in response to the output of the detecting element, and inclination for calculating the inclination to be a reference for boiling detection from the outputs of the first and second inclination detecting means The calculation means, the third inclination detection means for receiving the output of the temperature detection element to detect the inclination of the detected temperature at any time, and the output of the inclination calculation means and the output of the third inclination detection means are compared to boil. Boiling judgment to judge the start time It is an electromagnetic cooker and a stage.

A second means of the present invention is a cooking container receiver for receiving a cooking container, an induction heating coil arranged on the lower surface of the cooking container receiver for generating a high frequency magnetic field, and a temperature provided in the cooking container receiver. A temperature detecting element for detecting, a first inclination detecting means for detecting the inclination of the temperature change at the start of heating by receiving the output of the temperature detecting element, and a temperature change during the middle of heating by receiving the output of the temperature detecting element. The second inclination detecting means for detecting the inclination of, the fuzzy inference means for inferring the inclination which is the reference of boiling detection from the outputs of the first and second inclination detecting means, and the output of the temperature detecting element Electromagnetic provided with a third inclination detecting means for detecting the inclination of the detected temperature at any time, and a boiling determining means for comparing the output of the fuzzy inference means with the output of the third inclination detecting means to determine the boiling start point. To cook Than it is.

A third means of the present invention is, in addition to the first or second means, an electromagnetic cooker in which a temperature detecting element is provided in the central portion of the upper surface of the cooking container receiver.

The fourth means of the present invention is, in addition to the first or second means, a delay means for determining a delay time based on the output of the first inclination detection means and delaying the judgment of the boiling judgment means. An electromagnetic cooker equipped with.

The fifth means of the present invention is to detect a cooking container receiver for receiving a cooking container, an induction heating coil arranged on the lower surface of the cooking container receiver for generating a high frequency magnetic field, and a temperature provided in the cooking container receiver. Temperature detecting element, first inclination detecting means for detecting the inclination of the temperature change at the start of heating by receiving the output of the temperature detecting element, and receiving the output of the temperature detecting element for detecting the temperature change during the heating. Second inclination detecting means for detecting the inclination, inclination fuzzy inference means for inferring the inclination that serves as a criterion for boiling judgment from the outputs of the first and second inclination detecting means, and the first and second inclination detection Delay time fuzzy inference means for inferring the delay time for boiling judgment from the output of the means by fuzzy inference, third inclination detecting means for receiving the output of the temperature detecting element and detecting the inclination of the detected temperature at any time, and inclination fuzzy Of the boiling determination means for comparing the output of the logic means and the output of the third inclination detection means to determine the boiling start time, and the boiling time determination means for determining the delay time based on the output of the delay time fuzzy inference means. The electromagnetic cooker includes a delay unit that delays the determination.

[0010]

In the first means of the present invention, the boiling detection reference is set on the basis of the two detection values of the first inclination detecting means and the second inclination detecting means, so that boiling detection with high accuracy can be performed. It acts as an electromagnetic cooker capable of.

According to the second means of the present invention, the fuzzy inference means receives the information from the first and second inclination detecting means and fuzzy infers the optimum boiling detection reference. It acts as an electromagnetic cooker capable of.

[0012] The third means of the present invention is to act as an electromagnetic cooker capable of highly accurate boiling detection by devising the installation of the temperature detecting element.

In the fourth means of the present invention, the delay means acts so as to delay the boiling judgment by determining the delay time based on the output of the inclination detecting means, and more accurate boiling detection can be performed. It realizes a possible electromagnetic cooker.

Further, in the fifth means of the present invention, the slope fuzzy inference means infers an optimum boiling detection criterion, the delay time fuzzy inference means infers an optimum delay time, and the delay means is optimum for boiling judgment. Since it acts to have a delay, more accurate boiling detection is realized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes a cooking container such as a pot, the bottom surface of which is in close contact with the cooking container receiver 2. The cooking container receiver 2 is made of a ceramic plate or the like, and an induction heating coil 3 for generating a high frequency magnetic field is provided on the lower surface of the cooking container receiver 2. The high frequency current supplied to the induction heating coil 3 is a high frequency inverter circuit 4a connecting the high frequency current output section to the induction heating coil 3 and a high frequency current for controlling the oscillation of the high frequency inverter circuit 4a to control the high frequency output current. The coil current control means 4 including the inverter output control circuit 4b performs this. The coil current control means 4 includes a knob for adjusting the output of the induction heating coil 3. Reference numeral 5 denotes a temperature detecting element attached to the central portion of the lower surface of the cooking container receiver 2 for detecting the temperature. Reference numeral 6 denotes a start input means for the user to instruct the start of heating, which is composed of a switch. The user sets the cooking ingredients in the cooking container 1,
The start input means 6 is operated. Reference numeral 7 is an automatic boiling detection means which is the essence of this embodiment, and when a cooking start signal is received from the start input means 6, the coil current control means 4 is provided.
Send a heating start signal to. The automatic boiling detection means 7 includes a first inclination detection means 11, a second inclination detection means 12, an inclination calculation means 13, a third inclination detection means 14, and a boiling determination means 15.
It consists of.

The first inclination detecting means 11 receives the temperature information detected by the temperature detecting element 5 and detects the inclination of the temperature rise during the preset time dt ₁ from the heating start time t ₁ . Is. Further, the second inclination calculating means 12
Similarly, the temperature information from the temperature detection element 5 is received to detect the slope of the temperature increase from the preset temperature T ₁ to the temperature T ₂ having a predetermined temperature difference dT from T ₁ . It is a thing. The T ₁ is the first tilt detecting means 11
Is set at the timing when the tilt detection is completed. The outputs of the first tilt detecting means 11 and the second tilt detecting means 12 are sent to the tilt calculating means 13.

The inclination calculating means 13 determines a reference inclination based on these two pieces of inclination information.
The third inclination detecting means 14 receives the temperature detected by the temperature detecting element 5 similarly to the first and second inclination detecting means 11 and 12, and the second inclination detecting means 12 detects the second inclination. After that, the slope of the temperature rise is detected at any time. That is, the differential value of the temperature detected by the temperature detecting element 5 with respect to time is detected.

The boiling determining means 15 compares the output of the inclination calculating means 13 with the output of the third inclination detecting means 14,
When the output of the third inclination detecting means becomes smaller, it is determined as the boiling timing of the cooked food. At this boiling timing, the boiling determination means 15 drives the high frequency inverter output control circuit 4b constituting the coil current control means 4 to change the output to a preset output.

The operation of this embodiment will be described below. The cooking container 1 used in this embodiment is a dedicated container that comes into close contact with the cooking container receiver 2. That is, most of the high-frequency magnetic field generated by the induction heating coil 3 is effectively used for induction heating of the cooking container 1. Therefore, the temperature detection element 5 can detect an accurate and highly accurate temperature.

The operation of the automatic boiling detection means 7 will be described below with reference to FIG. It is assumed that the user has finished the preparation for cooking and operated the start input means 6 at time t ₁ . This signal is transmitted to the automatic boiling detection means 7. Automatic boiling detection means 7
When it receives this signal, it first resets itself to a mode in which boiling is not detected. At the same time, the coil current control means 4 is driven with the heating output set to the maximum. In this way, a high-frequency current is supplied to the induction heating coil 3, and the cooking container 1 starts to increase in temperature from time t ₁ . This temperature is detected by the temperature detecting element 5, and the first, second and third inclination detecting means 11, 12, 14 start operating.

[0021] The first tilt detection means 11 detects the inclination of the temperature rise of between time t ₁ and time t ₁ and time t ₂ having a predetermined time difference. That is, the first inclination is detected. The second inclination detecting means 12 receives the temperature information from the temperature detecting element 5 and increases the inclination of the temperature from the preset temperature T ₁ to the temperature T ₂ having a predetermined temperature difference dT from T _1. , The second inclination is detected. The slope of the temperature rise until the cooked product reaches boiling varies depending on the amount and type of the cooked product as described in the conventional example.
As a result of experiments, the inventors have found that when the cooking container 1 is dedicated, the slope of this temperature rise has a correlation with the first slope and the second slope. From the first and second slopes, the slope calculating means 13 calculates and determines the slope of the cooked food when boiling, in other words, the slope K ₁ that serves as a reference for temperature control, according to the following equation. There is something.

K ₁ = (second slope) / (C ₁ × (first slope) + C ₂ ) (where C ₁ and C ₂ are preset constants)
After determining the temperature control reference K in this way, the third inclination detecting means 14 receives the output of the temperature detecting element 5 and detects the third inclination at any time. The information indicating the third inclination is transmitted to the boiling determining means 15 together with the temperature control reference K ₁ to determine whether or not the boiling state is reached. That is, the boiling determination means 15 determines that the cooking product has reached the boiling state at the timing when the information indicating the third inclination has a value smaller than the temperature control reference K ₁ and then has a smaller value. It's a judgment.
When the boiling state is determined, the boiling determining means 13 acts to reduce the setting of the heating output of the coil current control means 4 to a preset value. Further, it is more preferable to notify that the boiling state has been reached at this time by using an appropriate means.

As described above, according to this embodiment, the boiling state can be detected accurately and automatically, so that the user can do another work, for example, with peace of mind.

Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those in the above embodiment are designated by the same reference numerals, and the following description will be omitted. Reference numeral 21 is an automatic boiling detection means, which has a fuzzy inference means 22. The fuzzy inference means 22 includes the following elements. 23 is shown in FIG.
The first slope membership storage means stores a membership function for inferring the degree of the first slope shown in (a). Reference numeral 24 is a first inclination adaptability calculating means for inferring the first inclination degree based on the output of the first inclination detecting means 11. Further, reference numeral 25 denotes a second inclination membership storage means for storing a membership function for inferring the degree of the second inclination shown in FIG. 4 (b). Reference numeral 26 is a second inclination adaptability calculating means for inferring the second inclination degree based on the output of the second inclination detecting means 12. The outputs of the first slope adaptability calculating means 24 and the second slope adaptability calculating means 25 are sent to the output adaptability calculating means 28 for calculating the slope which is the boiling control reference. The output fitness calculating means 28 sends this information to the output membership function storing means 27 once, and
The optimum output value for inferring the optimum output is determined from the membership function shown in (c). Upon receipt of this information, the output adaptability calculating means 28 finally determines the inclination which is the boiling control reference, and transmits this signal to the boiling determining means 15. The functions of the third inclination detecting means 14 and the boiling determining means 15 are the same as those in the above embodiment.

The operation of this embodiment will be described below. When the user operates the start input means 6 to start cooking, a high-frequency magnetic field is generated from the induction heating coil 3 to start heating the cooking container 1. The temperature of the cooking container 1 is detected by the temperature detecting element 5 provided in the cooking container receiver 2. The temperature information of the temperature detecting element 5 is sent to the first inclination detecting means 11 and then to the second inclination detecting means 12, and the fuzzy inference means 22 starts fuzzy inference. That is,
The first inclination adaptability calculating means 24, which has received the information on the temperature change at the initial stage of heating from the first inclination detecting means 11, sends this information to the first inclination membership function storing means 23,
The first slope in the initial heating is calculated and determined.

Further, the second inclination adaptability calculating means 26 which has received the information of the temperature change at the intermediate temperature from the second inclination detecting means 12 similarly sends this information to the second inclination membership function storing means 25. Then, the second slope at the intermediate temperature is calculated and determined. That is, the first inclination membership function storage means 23 evaluates the inclination degree of the temperature rise at the initial heating stage based on the fitness estimation rule shown in FIG. In other words, it is inferred to which stage the current temperature rise gradient is matched when it is divided into five stages from steep to gentle.

Upon receipt of this information from the first inclination detecting means 24, the first inclination adaptability calculating means 24 determines the first inclination and transmits this information to the output adaptability calculating means 28.
Similarly, the second slope adaptability calculating means 26 stores the second slope at the intermediate temperature and the second slope membership function storing means 25.
Is determined from the evaluation value evaluated based on FIG. 4 (b),
It is transmitted to the output adaptability calculating means 28. Upon receiving this information, the output adaptability calculating means 28 temporarily stores this information in FIG.
It is sent to the output membership function storage means 27 having the inference rule shown in FIG. Output membership function storage means 27
Calculates the optimum output value for estimating the gradient that serves as the boiling control reference from the degree of the first gradient and the degree of the second gradient.

Upon receipt of this information, the output adaptability calculating means 28 finally determines the inclination which serves as the boiling control reference, and transmits this signal to the boiling determining means 15. In the boiling determination means 15, the third inclination detection means 14 is the temperature detection element 5
The inclination of the temperature change which is detected at any time by receiving the output of the above and the boiling control reference are compared, and the third inclination detecting means 14
The time when the detection value of is smaller than the boiling control reference is determined as the boiling state. That is, the coil current control means 4 operates so as to be changed to a preset output and operated. Further, as in the above embodiment, it is more preferable to notify the user of the arrival of the boiling state by using an appropriate notification means.

As described above, according to this embodiment, since the optimum inference output by the fuzzy inference is used, it is possible to realize an electromagnetic cooker capable of detecting boiling with higher accuracy.

Next, a third embodiment of the present invention will be described with reference to FIG.
It will be described based on. The same parts as those in the above embodiment are designated by the same reference numerals, and the following description will be omitted. Reference numeral 31 is a temperature detecting element mounted so as to be embedded in the central portion of the upper surface of the cooking container receiver 2, and the contact surface between the cooking container receiver 2 and the cooking container 1 is flat. Reference numeral 32 denotes an automatic boiling detection means, which has an inclination calculation means 33 for calculating an inclination serving as a reference for temperature control from the outputs of the first inclination detection means 11 and the second inclination detection means 12.

The operation of this embodiment will be described below. In this embodiment, the temperature detecting element 31 is provided so as to detect the temperature of the central portion of the cooking container 1 on the upper surface of the cooking container receiver 2. The contact surface of the surface of the cooking container receiver 2 with the cooking container 1 is flat and uniform. Therefore, the temperature detection accuracy of the temperature detection element 31 is much higher than that of the structure of each of the embodiments. Therefore, the correlation between the slope of the temperature rise until the food reaches boiling and the first slope and the second slope is higher.

In the present embodiment, the inclination calculating means 33 has the first inclination detected by the first inclination detecting means 11 at the start of heating and the second inclination in the middle detected by the second inclination detecting means 12. By using and, the slope K ₂ which is the reference of the temperature control is calculated and determined by the following equation.

K ₂ = (second slope) / (C ₃ × (first slope) + C ₄ ) (where C ₃ and C ₄ are preset constants) Note that the above C ₃ and C ₄ Can be determined with higher accuracy than the constants C ₁ and C ₂ when K _{1 in the} above-mentioned embodiment is set.

The third inclination detecting means 14 receives the temperature information of the temperature detecting element 31 and detects the inclination of the temperature rise at any time, as in the above embodiment. Also, the boiling determination means 15
The inclination value K _{2 serving} as the temperature control reference is compared with the detection value of the third inclination detecting means 14, and the third inclination detecting means 14 is compared.
The boiling point is determined when the gradient detected by is smaller than the gradient value K ₃ that serves as the temperature control reference. That is, at this time, the coil current control means 4 is operated so as to be changed to a preset output and operated. Further, as in the above embodiment, it is more preferable to notify the user of the arrival of the boiling state by using an appropriate notification means.

As described above, according to this embodiment, the boiling state can be detected more accurately by devising the attachment of the temperature detecting element 31.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
It will be described based on. The same parts as those in the above-mentioned respective embodiments are designated by the same reference numerals, and the following description will be omitted. Reference numeral 41 denotes an automatic boiling detection means, which has a delay means 42 for delaying the boiling judgment made by the boiling judgment means on the basis of the output value of the first inclination detection means 11. That is, the delay means 42 delays the boiling determination by the boiling determination means 15 when the inclination detected by the first inclination detection means 11 is smaller than a predetermined value.

The operation of this embodiment will be described below. When the cooking container 1 is placed on the cooking container receiver 2, if a foreign substance such as dust adheres to the bottom back surface of the cooking container 1 or is set in an inclined state, the temperature detecting element 31 will cook. It no longer adheres to the container 1. In such a case, the temperature detection of the temperature detection element 31 is delayed with respect to the temperature rise of the food. In other words, the time at which the start of boiling is detected is also delayed in time. Therefore, in this embodiment, the inclination calculating means 33 determines the inclination K ₃ which is the temperature control reference shown by the following equation, based on the outputs of the first inclination detecting means 11 and the second inclination detecting means 12.

K ₃ = ((second slope) / (C ₅ × (first slope) + C ₆ )) * a C5 · C6: preset constant a: preset constant larger than 1, that is, this In the embodiment, the gradient K ₃ which is the temperature control reference is set to be large, in other words, boiling detection is performed at an early stage. In this state, the boiling determination means 15 outputs the output of the third inclination detection means 14 and the K
By comparing with ₃ , the arrival of the boiling state is detected. The output of the boiling determination means is the delay means 42.
Is sent to the coil current control means 4 via. At this time, when the delaying means 42 recognizes that the output of the first inclination detecting means 11 is smaller than usual, that is, it is in the state of the mounting abnormality described above, the output of the boiling determining means is directly used for the coil current control means. 4 to reduce the output of the coil current control means 4 to a predetermined value. When the delay means 42 recognizes that the output of the first inclination detection means 11 is normal, the output of the boiling determination means is delayed by a predetermined time and transmitted to the coil current control means 4 to transmit the coil current. The output of the control means 4 is reduced to a predetermined value. That is, the delay means 42 acts so as to delay the regular boiling determination timing by a predetermined time when the placement is abnormal.

As described above, according to this embodiment, by providing the delay means 42, it is possible to provide an electromagnetic cooker capable of coping with variations in the setting of cooking containers.

Next, a fifth embodiment of the present invention will be described with reference to FIG. Reference numeral 51 is an automatic boiling detection means, which has a fuzzy inference means 52. The fuzzy inference means 52 includes the following elements. Reference numeral 53 is a first slope membership function storage means for storing a membership function for inferring the degree of the first slope shown in FIG. Reference numeral 54 is a first inclination adaptability calculating means for inferring the first inclination degree based on the output of the first inclination membership function storage means 53. Reference numeral 55 is a second slope membership function storage means for storing a membership function for inferring the degree of the second slope shown in FIG. 8B. Reference numeral 56 is a second slope adaptability calculating means for inferring the second slope degree based on the output of the second slope membership function storage means 55. The outputs of the first slope adaptability calculating means 54 and the second slope adaptability calculating means 56 are sent to the output adaptability calculating means 58 for calculating the slope which is the boiling control reference. The output fitness calculating means 58 once sends this information to the output membership function storing means 57, and determines the optimum output value for inferring the optimum output from the membership function shown in FIG. 8C. . Upon receipt of this information, the output adaptability calculation means 58 finally determines the inclination that serves as the boiling control reference, and the boiling determination means 1
This signal is transmitted to 5.

The operation of this embodiment will be described below. When the user operates the start input means 6 to start cooking, a high-frequency magnetic field is generated from the induction heating coil 3 to start heating the cooking container 1. This temperature is accurately detected by the temperature detecting element 5, sent to the first inclination detecting means 11 and then to the second inclination detecting means 12, and the fuzzy inference means 5 is sent.
2 starts fuzzy reasoning. That is, the first inclination adaptability calculating means 54, which has received the information on the temperature change at the initial stage of heating from the first inclination detecting means 11, sends this information to the first inclination membership function storage means 53 to perform heating. The first inclination in the initial stage is calculated and determined.

Further, the second inclination adaptability calculating means 56 which has received the information of the temperature change at the intermediate temperature from the second inclination detecting means 12 similarly sends this information to the second inclination membership function storing means 55. Then, the second slope at the intermediate temperature is calculated and determined. That is, the first inclination membership function storage means 53 evaluates the inclination degree of the temperature rise at the initial heating stage based on the membership function shown in FIG. The membership function is designed so as to minimize the influence of fluctuations in thermal adhesion between the cooking container 1 and the cooking container receiver 2, in particular. That is, the degree of the initial temperature rise is influenced by the degree of adhesion between the cooking container 1 and the cooking vessel receiver 2, and therefore the estimation rule is such that the degree of this degree of adhesion can be evaluated. The first slope membership storage means 52 uses this rule to infer which stage the current slope of temperature rise corresponds to when it is divided into five stages from steep to gentle. It is a thing.

Upon receipt of this information from the first inclination detecting means 53, the first inclination adaptability calculating means 54 determines the first inclination and transmits this information to the output adaptability calculating means 58.
The second slope adaptability calculating means 56 similarly sets the second slope to the intermediate temperature, and the second slope membership function storing means 55.
Is determined from the evaluation value evaluated based on FIG. 8 (b),
This is transmitted to the output compatibility calculation means 58. The membership function stored in the second membership function storage means 55 is also designed to minimize the influence of the fluctuation of the thermal adhesion between the cooking container 1 and the cooking container receiver 2. There is. That is, the degree of temperature rise at the intermediate time is affected by the degree of adhesion between the cooking container 1 and the cooking container receiver 2,
The estimation rule is such that the degree of adhesion can be evaluated.

The output adaptability calculating means 58 receiving this information
Sends this information to the output membership storage means 57 provided with the inference rules shown in FIG. 8 (c). Figure 8 (c)
The inference rule shown in FIG. 4 can infer the reference value of the inclination for detecting boiling more accurately than that shown in FIG. Output membership storage means 57
Uses this inference rule to calculate the optimum output value for estimating the gradient that serves as the boiling control reference from the degree of the first gradient and the degree of the second gradient. Output fitness calculation means 5
8 receives this information, finally determines the inclination that serves as the boiling control reference, and transmits this signal to the boiling determination means 15.

At this time, in this embodiment, the fuzzy inference means 5 is used.
The inclination which is the boiling control criterion determined by 2 is set on the assumption that the cooking container 1 is placed on the cooking container receiver 2 in an abnormal manner, that is, is set to a slightly large setting. . For this reason, the boiling determination timing determined by the boiling determination means 15 is an appropriate determination timing when dust or the like is attached. That is, the delay means 42
When it is determined that the detection output of the first inclination detecting means 11 is smaller than a predetermined value and dust is attached or there is an abnormal placement, the output of the boiling determining means 15 is sent to the coil current control means 4 as it is, and the coil is immediately turned on. The output of the current control means 4 is reduced to a predetermined value. When the normal state is determined, the output of the boiling determination means 15 is delayed by a predetermined time to control the coil current control means 4.

As described above, according to the present embodiment, since the fuzzy inference means 52 and the delay means 42 are provided, the optimum inference output can always be obtained and the placement abnormality of the cooking container can be dealt with. .

Next, a sixth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the automatic boiling detection means 5
1 has a fuzzy inference means 62. The fuzzy inference means 62 includes a delay membership function storage means 63 for determining the delay time of the delay means 42 and a delay fitness calculation means 64.
It has and. The delay membership storage unit 63 includes the fitness estimation rule shown in FIG. This adaptability estimation rule is designed so as to reduce the influence of fluctuations in thermal adhesion between the cooking container 1 and the cooking container receiver 2, in particular.

The operation of this embodiment will be described below. From the information of the first inclination detecting means 11, both the calculation of the first inclination adaptability by the first inclination adaptability calculating means 54 and the delay time adaptability by the delay adaptability calculating means 64 can be determined. Therefore, the boiling determination timing of the boiling determination means 15 can be appropriately delayed according to the degree of thermal contact between the cooking container 1 and the cooking container receiver 2.

As described above, according to this embodiment, it is possible to realize an electromagnetic cooker capable of always making accurate and highly accurate boiling determination.

[0050]

The first means of the present invention comprises the first, second, and third inclination detecting means, the inclination calculating means, and the boiling determining means, and is capable of highly accurate boiling detection. It realizes an electromagnetic cooker.

The second means of the present invention comprises a first, a second, and a third inclination detecting means, a fuzzy inference means, and a boiling judging means, and uses the fuzzy inference to detect an optimum boiling point. It is possible to realize an electromagnetic cooker that can determine the reference value of, and can realize boiling detection with higher accuracy.

In the third means of the present invention, in addition to the first and second means, the temperature detecting element is provided in the central portion of the upper surface of the cooking container receiver, and it is possible to reduce variations in the detecting characteristics of the temperature detecting element. It is intended to realize an electromagnetic cooker capable of detecting boiling with high accuracy.

A fourth means of the present invention is, in addition to the first and second means, a delay means for determining a delay time based on the output of the first inclination detecting means and delaying the judgment of the boiling judging means. The present invention provides an electromagnetic cooker capable of coping with an abnormal state of placement of a cooking container and capable of detecting boiling with high accuracy.

The fifth means of the present invention comprises a first, a second, and a third inclination detecting means, a fuzzy inference means, a delay time fuzzy inference means, a boiling judging means, and a delay means. Can be determined with high accuracy, and an electromagnetic cooker capable of detecting boiling with higher accuracy can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram of an electromagnetic cooker according to a first embodiment of the present invention.

FIG. 2 is a temperature characteristic diagram showing the same operation.

FIG. 3 is a block diagram of an electromagnetic cooker according to a second embodiment of the present invention.

FIG. 4 is a diagram showing the contents of the fuzzy inference means.

FIG. 5 is a block diagram of an electromagnetic cooker according to a third embodiment of the present invention.

FIG. 6 is a block diagram of an electromagnetic cooker according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram of an electromagnetic cooker according to a fifth embodiment of the present invention.

FIG. 8 is a diagram showing the contents of the fuzzy inference means.

FIG. 9 is a block diagram of an electromagnetic cooker according to a sixth embodiment of the present invention.

FIG. 10 is a diagram showing a membership function included in the delay membership function storage means.

FIG. 11 is a block diagram of a conventional electromagnetic cooker.

FIG. 12 is a temperature characteristic diagram detected by a temperature detection element of the electromagnetic cooker.

[Explanation of symbols]

 1 Cooking Container 2 Cooking Container Receiver 3 Induction Heating Coil 4 Coil Current Control Means 5 Temperature Sensing Element 6 Start Input Means 7, 32, 41 Automatic Boiling Sensing Means 11 First Tilt Sensing Means 12 Second Tilt Sensing Means 13 Tilt Calculation Means 14 Third inclination detecting means 15 Boiling judging means 22, 52, 62 Fuzzy inference means 42 Delaying means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Machiko Miyai 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A cooking container receiver for receiving a cooking container, an induction heating coil arranged on a lower surface of the cooking container receiver for generating a high frequency magnetic field, a temperature detecting element for detecting a temperature provided in the cooking container receiver, A first inclination detecting means for receiving the output of the temperature detecting element and detecting the inclination of the temperature change at the start of heating, and a second inclination detecting means for receiving the output of the temperature detecting element and detecting the inclination of the temperature change during the heating. Inclination detecting means,
Inclination calculation means for calculating the inclination that serves as a reference for boiling detection from the outputs of the first and second inclination detection means, and third inclination detection for receiving the output of the temperature detection element and detecting the inclination of the detected temperature at any time. An electromagnetic cooker comprising: means and a boiling determination means for comparing the output of the inclination calculation means and the output of the third inclination detection means to determine the boiling start time. 2. A cooking container receiver for receiving a cooking container, an induction heating coil arranged on a lower surface of the cooking container receiver for generating a high frequency magnetic field, a temperature detecting element provided in the cooking container receiver for detecting a temperature, A first inclination detecting means for detecting the inclination of the temperature change at the start of heating by receiving the output of the temperature detecting element, and a second inclination detecting means for receiving the output of the temperature detecting element and detecting the inclination of the temperature change during the heating. Inclination detection means, fuzzy inference means for inferring the inclination that serves as a reference for boiling detection from the outputs of the first and second inclination detection means, and the inclination of the detected temperature is detected at any time by receiving the output of the temperature detection element. An electromagnetic cooker comprising: a third inclination detecting means; and a boiling determining means for comparing an output of the fuzzy inference means and an output of the third inclination detecting means to determine a boiling start time. 3. The electromagnetic cooker according to claim 1, wherein the temperature detecting element is provided in a central portion of an upper surface of the cooking container receiver. 4. The electromagnetic cooker according to claim 1, further comprising a delay unit that determines a delay time based on the output of the first inclination detection unit and delays the determination of the boiling determination unit. 5. A cooking container receiver for receiving the cooking container, an induction heating coil disposed on the lower surface of the cooking container receiver for generating a high frequency magnetic field, a temperature detecting element for detecting the temperature provided in the cooking container receiver, and this temperature. First inclination detecting means for detecting the inclination of the temperature change at the start of heating by receiving the output of the detecting element, and second inclination for detecting the inclination of the temperature change during the middle of heating by receiving the output of the temperature detecting element Detecting means, inclination fuzzy inference means for inferring an inclination that serves as a criterion for boiling determination from outputs of the first and second inclination detecting means, and boiling by fuzzy inference from outputs of the first and second inclination detecting means. Delay time fuzzy inference means for inferring the delay time of judgment,
The boiling start time is determined by comparing the output of the third fuzzy inference means with the output of the third fuzzy inference means and the third tilt sensing means that detects the tilt of the detected temperature at any time by receiving the output of the temperature sensing element. An electromagnetic cooker comprising a boiling determining means for controlling the boiling time and a delay means for delaying the determination of the boiling determining means by determining a delay time based on the output of the delay time fuzzy inference means.