JP2003282228A - Induction heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the temperature of a pan from abnormally rising due to incorrect detection of the temperature when using a pan made of non- magnetic material such as aluminum or the pan floats up while controlling the temperature. <P>SOLUTION: When a material detection part detects that the pan is made of the non-magnetic material or when the pan is floating, a function of temperature control is stopped. A user is informed to manually adjust the temperature. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a household induction heating cooker.

[0002]

2. Description of the Related Art An induction heating cooker has an induction heating coil (hereinafter referred to as a heating coil) of 20 KHz to 60 KHz.
To generate a high-frequency magnetic field and generate an eddy current due to electromagnetic induction in a heated object such as a pot placed close to the heating coil. The object to be heated is heated by Joule heat due to this eddy current. Since the electromagnetic induction is used, it is desirable that the object to be heated is a magnetic material such as iron or magnetic stainless steel. However, in recent years, induction heating cookers that can heat non-magnetic pots such as aluminum and copper (hereinafter simply referred to as pots) to be heated have been put into practical use, and the range of use of induction heating cookers is expanding. .
In the induction heating cooker, the direction of the eddy current generated in the pan during heating is opposite to the direction of the current flowing through the heating coil. Therefore, a magnetic repulsive force is generated between the pan and the heating coil. On the other hand, since an electromagnetic force also acts between the heating coil and the pot, when the pot is made of a magnetic material such as iron, a magnetic attractive force is generated between the heating coil and the pot. In a magnetic pot, the attractive force is usually greater than the repulsive force, so the pot is attracted to the heating coil.

However, in the case of a pot made of a non-magnetic material such as aluminum or copper (hereinafter referred to as a non-magnetic pot), the above-mentioned attractive force does not work but only the repulsive force works. Therefore, the weight including the contents of the non-magnetic pan is light, and when the gravity is smaller than the repulsive force, the non-magnetic pan causes a "pot float" to float away from the heating coil due to the repulsive force. When the pan floats, the pan may move on a top plate such as a heat-resistant glass plate provided on the heating coil for placing the pan. Since non-magnetic pots are made of materials with low magnetic permeability and resistivity, such as aluminum and copper, in order to ensure the same amount of heat generation as iron pots, higher frequency Electric current needs to be passed through the heating coil. Therefore, the repulsive force is larger than in the case of the iron pot, and the pot is likely to float.

As the first prior art relating to the use of a non-magnetic material pan in an induction heating cooker, Japanese Patent Laid-Open No. Sho 61-61
There is one disclosed in Japanese Patent Publication No. 128492. In the first prior art, a weight sensor for detecting the weight of the pan is provided on the surface of the top plate to detect the weight of the pan. Further, the high frequency current flowing through the heating coil is detected by the current transformer, and the material of the pot is detected based on the detected output. When the weight of the pan including the contents is less than a predetermined value and the material of the pan is aluminum or copper, the pan may float, so the high frequency current of the heating coil is cut off to stop the heating. Even if the pot material is aluminum, copper, etc., when the weight of the pot exceeds a predetermined value, there is no risk of the pot floating, so heating is performed by passing a high frequency current through the heating coil.

As a second prior art relating to the use of a non-magnetic pan in an induction heating cooker, Japanese Patent Laid-Open No. 62-62160
There is one disclosed in Japanese Unexamined Patent Publication No. 276787. Also in the second prior art, the weight and material of the pot are detected as in the first prior art. If the material of the pan is a high conductivity non-magnetic material such as aluminum, the frequency of the high frequency current is 50 KHz.
Raise it to 20 KHz for an iron pot so that such a pot can generate the same amount of heat as an iron pot. In addition, the high-frequency current flowing through the heating coil is adjusted according to the weight of the pan to control the current value within the range where the pan does not float. When cooking with a pan, if you control the temperature so that the temperature of the object to be heated in the pan is maintained at a desired value, you will not have to burn the object and can get. In particular, when putting oil in a pan and frying the tempura, it is important to keep the temperature of the oil at an appropriate value for frying the delicious tempura. In the above-mentioned first and second prior arts, it is not shown that temperature control is performed during cooking, but an induction heating cooker having such a temperature control function is also put into practical use.

[0006]

In the induction heating cooker of the first prior art, when the weight of the pan containing the contents is less than a predetermined value, the high frequency current is cut off, so a non-magnetic pan is used. I can't cook. For example, it cannot be used for cooking with a small amount of food in a small home. In the second prior art induction cooker, the current in the heating coil is limited according to the weight of the pan containing the contents,
A light saucepan containing a small amount of food will weaken the heating power and cannot be cooked as desired by the user.

In order to control the temperature of the food to be cooked in the pan, it is necessary to detect the temperature of the food to be cooked. Since it is not easy to directly measure the temperature of the food to be cooked, the temperature of the bottom of the pot is usually indirectly detected by a temperature sensor. The temperature sensor is provided on the lower surface of the top plate on which the pan is placed, and when the pan is placed on the top plate, the temperature of the bottom of the pan is detected via the top plate. Therefore, normal temperature detection is performed only when the pan is in contact with the top plate. If you use a non-magnetic pan and the pan floats,
The pan may float, or the pan may move on the top plate and deviate from the normal position, causing the temperature sensor to be unable to detect the temperature of the bottom of the pan correctly. In this state, the temperature sensor gives a detection output indicating that the temperature is low to the control unit, and the control unit increases the high frequency current supplied to the heating coil in order to further raise the temperature. As a result, normal temperature control may not be performed, and the temperature of the pan and the object to be heated may rise abnormally. SUMMARY OF THE INVENTION It is an object of the present invention to provide an induction heating cooker having a temperature control function, which can prevent an abnormal temperature rise when performing cooking using a non-magnetic pan such as aluminum. To do.

[0008]

According to the induction heating cooker of the present invention, when an object to be heated having a conductivity substantially equal to or higher than the conductivity of aluminum is heated, the heating is based on the detection result of the temperature sensor. Stop or suppress output control. This prevents an abnormal temperature rise of the object to be heated.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The induction heating cooker according to the first aspect of the present invention induction-heats a non-magnetic object to be heated or an iron-based object to be heated which has a conductivity substantially equal to or higher than that of aluminum. Heating coil, an inverter unit for flowing a high-frequency current through the induction heating coil, a temperature sensor for detecting the temperature of the object to be heated, and a heating output of the heating coil is controlled based on a detection result of the temperature sensor. Based on the detection result of the temperature sensor, the temperature control unit includes a temperature control unit, and when the temperature control unit recognizes that the non-magnetic object to be heated having a conductivity substantially equal to or higher than the conductivity of the aluminum is heated. The temperature control is stopped or suppressed. The induction heating cooker according to the invention of claim 2 has a material detection unit for detecting the material of the object to be heated, and the temperature control unit determines the conductivity of aluminum based on the detection result of the material detection unit. It is recognized that a non-magnetic object to be heated having the same or higher conductivity is heated.

The induction heating cooker according to the third aspect of the present invention heats a non-magnetic heated object having a conductivity substantially equal to or higher than the conductivity of aluminum or a heated material of another material. And a temperature control unit, based on the selection result of the heated body selection means, the non-magnetic heated body having a conductivity substantially equal to or higher than the conductivity of aluminum. I try to recognize that my body is heated. The induction heating cooker according to the invention of claim 4 has a positional deviation detecting means for detecting floating or positional deviation of the object to be heated, and the temperature control section is configured to detect the aluminum based on the detection result of the positional deviation detecting means. It is recognized that a non-magnetic object to be heated having an electric conductivity substantially equal to or higher than the electric conductivity of is heated. The induction heating cooker according to the invention of claim 5 comprises notifying means for visually or audibly notifying the user, and the notifying means is such that the temperature controller has a conductivity substantially equal to or higher than that of aluminum. When recognizing that the non-magnetic object to be heated having a temperature is heated and stopping or suppressing the control of the heating output based on the detection result of the temperature sensor, a notification to that effect is given.

An induction heating cooker according to a sixth aspect of the present invention comprises notifying means for visually or audibly notifying a user, and the notifying means is such that the temperature control section is substantially equal to the conductivity of the aluminum. When it is recognized that a non-magnetic object having a conductivity higher than that is to be heated, the fact is notified. The induction heating cooker according to the invention of claim 7 is an induction heating coil provided in the vicinity of a position where an object to be heated such as a pot is placed, an inverter section for supplying a high frequency current to the induction heating coil, and the object to be heated. Is a magnetic material or a non-magnetic material having high conductivity, a material detection unit, a positional deviation detector for detecting positional deviation of the heated object with respect to the induction heating coil, and temperature control of the heated object. In order to detect the temperature of the object to be heated, the detection outputs of the temperature sensor, the material detector and the position deviation detector are input, and the temperature of the object to be heated is controlled based on the detection output of the temperature sensor. And a detection signal when the material detection unit detects a non-magnetic and high-conductivity object to be heated, and the positional deviation detector to be heated. of a body When the detection signal when detecting a location shift, is one of the detection signal is inputted, it has a stop or suppress control unit the operation of the temperature control. According to the present invention, when the detection signal of any one of the material detection unit and the positional deviation detection unit is input to the control unit, the temperature control operation is stopped or suppressed,
It is possible to prevent an abnormal temperature rise of the object to be heated due to the temperature control in the state where the temperature sensor cannot normally detect the temperature of the object to be heated.

An induction heating cooker according to an eighth aspect of the present invention has a display section for displaying a notification to the user when the control section stops or suppresses the temperature control operation. Since the user can know that the operation of the temperature control has been stopped or suppressed, the temperature can be manually adjusted thereafter and the cooking can be continued. The induction heating cooker according to a ninth aspect of the present invention has an operating means for instructing the user to stop the temperature control operation when the object to be heated is a non-magnetic material having high conductivity. When the user recognizes that the object to be heated is a non-magnetic material, the temperature control operation can be stopped in advance, so that no notification by display or voice is received.

A preferred embodiment of the induction heating cooker of the present invention will be described below with reference to FIGS. 1 to 6. << First Embodiment >> A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of an induction heating cooker having a temperature control function of this embodiment. In the figure, a top plate 2 made of a heat-resistant glass plate or the like is attached to an upper part of a housing 1, and a user places a pot 3 or the like for cooking on the top plate 2. An induction heating coil 4 is provided in the housing 1 below the top plate 2 with a predetermined distance from the pan 3. On the upper surface of the top plate 2, the position where the pot 3 should be placed is shown in a pattern such as a circle.
A temperature sensor 7 and a pot floating detector 8 are provided on the lower surface of the top plate 2 in the area indicated by a circle. The temperature sensor 7 detects the temperature of the bottom of the pan 3 via the top plate 2. The pot floating detector 8 is a position shift detector that detects a position shift in which the pot 3 that is the object to be heated floats or moves with respect to the induction heating coil 4. A material detection unit 9 that detects the material of the pot 3 is provided in the housing 1.

A control unit 10 and an inverter unit 11 are provided in the housing 1. The control unit 10 is applied with the respective detection outputs of the temperature sensor 7, the pan floating detector 8 and the material detecting unit 9. As shown in the front view of the operation unit 12 of FIG. 2, the operation unit 12 provided on the side surface of the housing 1 close to the user has a temperature control selection switch 12A, a temperature setting switch 12B, and a heating start switch 12C. Is provided,
Each is connected to the control unit 10. A display unit 14 connected to the control unit 10 is provided near the operation unit 12 of the top plate 2. The output end of the control output of the control unit 10 is connected to the input end of the inverter unit 11. The output terminal of the inverter unit 11 is the terminal 4 of the induction heating coil 4.
1 and 42 are connected. A current transformer 44 (hereinafter referred to as CT44) that detects an input current of the inverter unit 11 is provided. The current signal 45 of the detection output of CT44 is input to one input end of the material detection unit 9. At the other input end of the material detection unit 9, the inverter unit 1
The voltage signal 46, which is a detection voltage corresponding to the voltage value applied to the induction heating coil 4 from 1, is input. The material detecting unit 9 detects the material of the pot based on the input current (I) and the voltage (V) of the induction heating coil corresponding to the current signal 45 and the voltage signal 46, respectively. The control unit 10 and the inverter unit 11 are connected via a power line 17 to, for example, an AC10.
It is connected to an AC power source of 0V.

The operation of the induction heating cooker of the present embodiment constructed as above will be described. The temperature sensor 7 is
For example, it has a temperature detecting element such as a thermistor, and when the pan 3 is placed at a predetermined position on the top plate 2, the temperature of the bottom of the pan 3 is detected. The induction heating cooker of the present embodiment has a temperature control unit in the control unit 10 for controlling the temperature of the pan 3 to be maintained at the set temperature set by the user based on the detection output of the temperature sensor 7. There is. The pot floating detector 8 is, for example, a capacitance detection type proximity switch, and detects “pot floating” which is a phenomenon that the pot 3 floats on the top plate 2. The material detecting unit 9 is a detector that detects whether the material of the pot 3 is magnetic or non-magnetic, and determines the material of the pot based on the current of the heating coil 4 and the voltage between both terminals, as will be described later. To detect.
The temperature control selection switch 12A is a switch that allows the user to select whether to perform temperature control. The temperature setting switch 12B is a switch for the user to set the heating temperature, and can set a desired temperature within a predetermined range. The heating start switch 12C is an "ON" or "OFF" switch for operating the start and end of heating. Display unit 14
Is a display device for displaying the operating state of the induction heating cooker of the present embodiment.

An example of the known detection principle of the material detecting section 9 will be described below. FIG. 3 shows a current-voltage characteristic curve of the induction heating coil 4 in which the horizontal axis represents the input current (I) and the vertical axis represents the voltage (V) of the induction heating coil. In FIG. 3, when the pot 3 is iron, the current-voltage characteristics shown in the curve A are obtained, and when the pot 3 is stainless steel (18-8) which has a lower conductivity than aluminum and is a non-magnetic material, the current-voltage characteristic shown in the curve B is shown. It becomes a characteristic. When the pot 3 is a non-magnetic material having a high conductivity such as aluminum, the current-voltage characteristic shown by the curve C is obtained. In the curves A, B and C of FIG. 3, for the same input current I1, the voltage V becomes V1 in the curve A, V2 in the curve B, and V3 in the curve C. By detecting the difference in the voltage V, it is possible to determine whether the material of the pot 3 is aluminum or the like, non-magnetic stainless steel, or iron system. The above detection principle is an example, and other methods may be used for detection. When the user heats and cooks using the induction heating cooker according to the present embodiment, first, the pot 3 containing the food to be cooked is placed in a predetermined area, such as a circle, of the top plate 2.

The operation when the user heats and cooks using the induction heating cooker of this embodiment will be described with reference to the flowchart of FIG. The user can perform temperature control by turning on the temperature control selection switch 12A in the induction heating cooker according to the present embodiment in advance according to an instruction manual or the like. Only when using a pan, when using a pan 3 made of a non-magnetic material such as aluminum, the conditions for use have been informed so as to turn off the temperature control selection switch 12A.
Hereinafter, this is referred to as "use condition". Therefore, when the user who knows the use conditions uses the non-magnetic pan 3, the temperature control selection switch 12A is turned off and the heating start switch 12C is turned on to start heating ( Figure 3
Step S0). In this case, the temperature is manually adjusted (step S5). When the user uses the pan 3 made of a magnetic material such as iron, the temperature control function can be used by turning on the temperature control selection switch 12A.

When a user who does not know the above-mentioned use conditions cooks using the non-magnetic pan 3, if the temperature control selection switch 12A is set to "ON" for heating (the same step) In step S1), the material detection unit 9 detects that the material of the pot 3 is a high conductivity material such as aluminum and copper and is a non-magnetic material (step S2), and gives a detection signal to the control unit 10. As a result, the control unit 10 automatically turns off the temperature control selection switch 12A, stops temperature control, and switches to manual adjustment (step S3). Stopping temperature control is called "stop". In this case, a message such as "The temperature of the aluminum pan cannot be controlled, please adjust the temperature manually" is displayed on the display unit 14 (step S4). If necessary, it may be announced by voice or an alarm may be given. As a result, the user knows that the temperature of the non-magnetic pot 3 cannot be controlled, and thereafter, the temperature can be manually adjusted for cooking (step S5). The control unit 10 has a temperature control selection switch 12
Instead of automatically turning A off, the temperature control conditions such as lowering the set temperature for temperature control may be changed automatically. Changing the temperature control conditions in this way is called "suppression" of the temperature control. When the detection signal indicating that the pot material is a non-magnetic material is not output, that is, when the pot 3 is iron or the like, heating by the automatic temperature control function is continued under a predetermined setting condition (step S6).

When the material detection unit 9 does not operate well due to a failure or when the pot floats unexpectedly, the pot float detector 8 detects it (step S7). When the pan floating detector 8 detects the pan floating, a signal indicating the pan floating is given to the control unit 10 and the temperature control selection switch 12A is automatically turned off (step S3). At this time, the above-mentioned display and announcement that the temperature cannot be controlled (due to the floating of the pan) are made (step S4). Since the temperature control selection switch 12A is turned off and the user manually adjusts the temperature (step S5), even if the pan floats, the abnormal temperature rise of the pan 3 should be prevented. You can If the detection output of the pan floating detector 8 is not output, heating by the automatic temperature control function is continued under a predetermined setting condition (step S6). Necessary heating is performed either by continuing the heating by the above-mentioned automatic temperature control under a predetermined setting condition (step S6) or by manually adjusting heating by switching to manual temperature control (step S5). When the heating and cooking is completed, the user turns off the heating start switch 12C to end the heating and cooking (step S9).

<Second Embodiment> A second embodiment of the present invention will be described with reference to FIGS. 1, 5 and 6. The induction heating cooker according to the second embodiment is replaced with the operation unit 12 in FIG.
The operation unit 22 shown in FIG. 5 is provided. The operation unit 22 includes a heated body selection switch 12D. The other structure is substantially the same as that of the first embodiment shown in FIG. The heated body selection switch 12D is connected to the control unit 10 shown in FIG. 1, and the control unit 10 has a control function of controlling the inverter unit 11 as described in detail below. The heated object selection switch 12D is used by a user to select a heated object such as a pan 3 made of a material having a conductivity substantially equal to or higher than that of aluminum (hereinafter abbreviated as an aluminum pan 3). It is a switch used for heating and cooking while controlling the temperature. When the cooking is performed while controlling the temperature using the aluminum pot 3, the pot may float or the pot may move so that the heating cannot be performed normally. I have no control. But that is often inconvenient. The present embodiment is intended to provide an induction heating cooker capable of safely heating and cooking even if the temperature is controlled using the aluminum pot 3.

The operation of this embodiment will be described in detail with reference to FIGS. 1, 5 and 6. When the user heats and cooks while controlling the temperature using the aluminum pot 3, "aluminum" of the heated object selection switch 12D of the operation unit 22 shown in FIG.
The switch indicated by is pressed to select it (step S21 in the flowchart of FIG. 6). Further, the temperature control selection switch 12A is set to "ON" (step S22), and the desired temperature is set by the temperature setting switch 12B. Step S
When the heating start switch 12C is set to "ON" at 23, the process proceeds to step S24, and the display section 14 displays "The temperature is controlled using an aluminum pot". Step S
In 25, if the pan floating detector 8 detects the occurrence of pan floating, the process proceeds to step S26. The pan floating detector 8 detects the pan floating state based on the level of the detection output and the level change. When the pan floats, one of the pans 3 temporarily or continuously floats, the pan 3 vibrates up and down on the top plate 2,
There are various states such as the state where the pot 3 is completely floated on the top plate 2. In step 26, it is determined whether the floating state of the pot is within the safe range or not according to a standard defined in advance. For example, a state where a part of the pot 3 is momentarily lifted up or a state where it is slightly vibrated may be defined as a safe range. The state where the pan 3 is completely lifted above the top plate is not a safe range. Step S26
If the state of floating the pan is not within the safe range, step S2
7, the temperature control selection switch 12A is automatically turned off to stop the temperature control. Also switch to manual adjustment. At this time, it is desirable to slightly reduce the input power of the induction heating coil. If the pan floating state is within the safe range, the process proceeds to step S31 to suppress the temperature control. The "suppression" of the temperature control automatically lowers the temperature set by the temperature setting switch 12B. At this time, the display unit 14 displays "The set temperature has been lowered by 5 ° C." or the like to notify the user (step S32). While the temperature control is suppressed, the temperature control is being performed although the set temperature is lowered. During heating and cooking, the process returns to step S26 via step S33 to determine whether the floating state of the pan is within the safe range.

When the mode is switched to the manual adjustment in step S27, "Please manually adjust the temperature" is displayed on the display section 14 (step S28). The user recognizes that the temperature is not controlled by this display,
After that, the temperature is manually adjusted (step S29). Upon completion of heating and cooking, the process proceeds to step S30. Step S
At 30, the user turns off the heating start switch 12C to end the cooking. Steps S24 and S
It is desirable that the display in 28 and S32 be informed by characters or voice. If necessary, an alarm sound such as a chime may be emitted. According to this embodiment, the aluminum pot 3
Since the temperature can be safely controlled even when using, the effect of expanding the range of cooking using the induction heating cooker can be obtained. Although the pot is made of aluminum in this embodiment, it is needless to say that the same effect can be obtained as long as it is made of a non-magnetic material having a conductivity equal to or higher than that of aluminum. Further, even if the pot is a combination of these materials and other materials, the same effect can be obtained as long as the pot itself has the same characteristics as aluminum in the induction heating.

[0023]

As described in detail in the above embodiments,
According to the invention of claim 1, when heating a non-magnetic object having a conductivity substantially equal to or higher than that of aluminum, the control of the heating output performed based on the detection result of the temperature sensor is stopped or Since the temperature is suppressed, it is possible to prevent an abnormal temperature rise caused by the floating of the pot and the like, and a correct detection value not being obtained from the temperature sensor. According to the invention of claim 2, the temperature control unit stops or suppresses the control of the heating output based on the detection result of the temperature sensor according to the detection result of the material detection unit. Therefore, the material of the object to be heated is substantially aluminum. In the case of a non-magnetic object to be heated having the same or higher conductivity, its material is detected and the control of the heating output is stopped or controlled to prevent an abnormal temperature rise of the object to be heated.

According to the third aspect of the present invention, the heating selection means determines whether the heating target is a non-magnetic heating target having a conductivity substantially equal to or higher than that of aluminum, or a heating target made of another material. Can be selected by the user. Depending on the selection result, since the control of the heating output of the temperature control based on the detection result of the temperature sensor is stopped or suppressed, when an object to be heated such as aluminum is not suitable for temperature control, an abnormal object to be heated is used. The temperature rise can be prevented. According to the invention of claim 4, the temperature control is stopped or suppressed when the floating or the positional deviation of the object to be heated is detected. Therefore, it is possible to prevent an inappropriate temperature control when the floating or the positional deviation of the object to be heated occurs. It is possible to prevent an abnormal temperature rise of the object to be heated.

According to the fifth aspect of the present invention, there is provided notifying means for visually or audibly notifying the user, and in the notifying means, the temperature controller has a conductivity substantially equal to or higher than that of aluminum. When the user recognizes that a non-magnetic object to be heated having a temperature is heated and stops or suppresses the control of the heating output based on the detection result of the temperature sensor, the user is informed of that fact. You can know. According to the invention of claim 6, when a non-magnetic object having a conductivity substantially equal to or higher than the conductivity of aluminum is heated, a non-magnetic substance having a conductivity substantially equal to or higher than the conductivity of aluminum is heated. By recognizing that the object is a magnetic object or a ferrous object, the fact is displayed and the user is notified, so that the user can cook while paying attention to the heating state. According to the invention of claim 7,
If you try to control the temperature using a pan made of non-magnetic material such as aluminum, the temperature control function is automatically stopped or suppressed by the detection output of the material detection unit or the pan floating detection unit. Therefore, even when the pan floats and the temperature sensor cannot correctly detect the temperature of the pan, it is possible to prevent an abnormal temperature rise of the pan.

According to the eighth aspect of the invention, when the temperature control function is stopped or suppressed, the user is informed by the display, and the user is prompted to manually adjust the temperature. Therefore, the user can know the current state of "ON" and "OFF" of the temperature control and the required manual control thereafter, and can use the induction heating cooker correctly. According to the invention of claim 9, since the user who knows the use condition stops the temperature control function in advance, it is not necessary to receive an unnecessary display message or voice notification.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of an induction heating cooker according to a first embodiment of the present invention.

FIG. 2 is a plan view of an operation surface of an operation unit 12 of the induction heating cooker according to the first embodiment.

FIG. 3 is a graph of a current-voltage characteristic curve for explaining a known operation principle of the material detection unit.

FIG. 4 is a flowchart showing the operation of the first embodiment of the induction heating cooker of the present invention.

FIG. 5 is a plan view of an operation surface of an operation unit 22 of the induction heating cooker according to the second embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the induction heating cooker according to the second embodiment of the present invention.

[Explanation of symbols]

1 case 2 top plate 3 pots 4 induction heating coil 7 Temperature sensor 8 Pan floating detector 9 Material detector 10 Control unit 11 Inverter section 12, 22 Operation part 12A Temperature control selection switch 12B temperature setting switch 12C heating start switch 12D heated object selection switch 14 Display 17 power line 44 CT (input current detection means)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroo Izumi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Takahiro Miyauchi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. (72) Inventor Atsushi Fujita             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 3K051 AA02 AA08 AB04 AB14 AC03                       AC07 AC33 AC37 AD07 AD09                       AD14 AD17 AD29 CD17

Claims (9)

[Claims] 1. A heating coil for inductively heating a non-magnetic object to be heated or an iron-based object to be heated having a conductivity substantially equal to or higher than that of aluminum, and a high frequency current is applied to the induction heating coil. An inverter unit for flowing the temperature, a temperature sensor for detecting the temperature of the object to be heated, and a temperature control unit for controlling the temperature by controlling the heating output of the heating coil based on the detection result of the temperature sensor, the temperature control The unit stops or suppresses temperature control based on the detection result of the temperature sensor when it recognizes that it heats a non-magnetic object having a conductivity substantially equal to or higher than the conductivity of aluminum. Induction heating cooker. 2. A material detecting section for detecting a material of an object to be heated, wherein the temperature control section has a conductivity substantially equal to or higher than that of aluminum based on a detection result of the material detecting section. The induction heating cooker according to claim 1, wherein the non-magnetic object to be heated is recognized to be heated. 3. A heated body selection means for selecting whether to heat a non-magnetic heated body having a conductivity substantially equal to or higher than that of aluminum or a heated body made of another material. However, the temperature control unit recognizes that the non-magnetic object to be heated has a conductivity substantially equal to or higher than the conductivity of aluminum, based on the selection result of the object to be heated selection means. The induction heating cooker according to Item 1. 4. A positional deviation detecting means for detecting floating or positional deviation of the object to be heated, wherein the temperature control section is substantially equal to the conductivity of aluminum based on the detection result of the positional deviation detecting means. The induction heating cooker according to claim 1, wherein it is recognized that a non-magnetic object having a conductivity higher than that is heated. 5. An informing means for visually or audibly informing a user, wherein the informing means has a temperature control portion having a conductivity substantially equal to or higher than the conductivity of aluminum. Induction heating according to any one of claims 1 to 4, wherein when recognizing that the heating is performed and stopping or suppressing the control of the heating output based on the detection result of the temperature sensor, a notification to that effect is given. Cooking device. 6. An informing means for visually or audibly informing a user, wherein the informing means has a non-magnetic material whose temperature control section has a conductivity substantially equal to or higher than that of the aluminum. The induction heating cooker according to any one of claims 1 to 4, wherein when recognizing that the heating body is heated, the fact is notified. 7. An induction heating coil provided in the vicinity of a position where a heated object such as a pan is placed, an inverter section for supplying a high frequency current to the induction heated coil, the heated object is a magnetic material, or a high conductive material. Material detecting section for detecting whether the object to be heated is a non-magnetic material, a position deviation detector for detecting a position deviation of the object to be heated with respect to the induction heating coil, or a member of the object to be heated for controlling the temperature of the object to be heated. A temperature sensor that detects a temperature, and a control output that receives the detection outputs of the temperature sensor, the material detection unit, and the position shift detection unit, and that performs the temperature control operation of the object to be heated based on the detection output of the temperature sensor. A detection signal when the material detection unit detects a non-magnetic and high conductivity object to be heated, and the position deviation detector detects a position deviation of the object to be heated. Shi When the detection signal, the one of the detection signal is input in time,
An induction heating cooker having a control unit that stops or suppresses the temperature control operation. 8. The induction heating cooker according to claim 7, further comprising a display unit for displaying a notification to the user when the control unit stops or suppresses the temperature control operation. 9. The induction heating cooker according to claim 7, further comprising operation means for instructing a user to stop the operation of temperature control when the object to be heated is a non-magnetic material having high conductivity.