JP2008117722A - Electromagnetic cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic cooker in which temperature distribution on the bottom face of a heated material such as a frying pan or the like can be uniformalized at a time of cooking a fried food using the heating material. <P>SOLUTION: The elecromagnetic cooker is provided with a heating means 4 that has two heating coils 4a, 4b which are placed on a nearly concentric circle center and a nearly same plane and having different diameters, a top plate 5, a high frequency electric power generating circuit 2 that heats the heated material 6 on the top plate by driving the heating means 4, and a control circuit 3 that controls the power output of the high frequency electric power generating circuit, and the control circuit 3 has a frying mode in which the heating coil 4b arranged outside is always driven, and the heating coil 4a arranged inside is driven or stopped, or driven and stopped. By this, by using the material frying mode, the electric power that is input into the outer peripheral part of the bottom face of the heated material 6 at the cooking time can be increased, and the temperature distribution at the bottom face of the heated material can be uniformalized so that baking irregularity can be suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electromagnetic cooker used in general homes, offices, restaurants and the like.

  Conventionally, this type of electromagnetic cooker has one heating coil formed in a spiral shape for one object to be heated, and controls and adjusts the output power of a high-frequency inverter that drives one heating coil. There is an electromagnetic cooker that adjusts the temperature of a heated object (see, for example, Patent Document 1).

In addition, in an electromagnetic cooker in which heating coils are arranged substantially concentrically and substantially in the same plane and each of the heating coils having different diameters is individually driven by a high-frequency power circuit, when one heating coil is driven, the other There is also known a technique for controlling and adjusting individual high-frequency power while preventing the heating coil from being driven (see, for example, Patent Document 2).
JP 200431247 A JP-A-8-78148

  However, in the above-described configuration disclosed in Patent Document 1, the magnetic flux generated by the heating coil is maximized near the center in the radial direction of the heating coil, so that the bottom temperature of the object to be heated is near the center in the radial direction of the heating coil. There is a problem that unevenness of heating occurs due to a donut-shaped temperature distribution that becomes higher and lower in other places.

  Moreover, in the technique of patent document 2, the heating coil is divided into a plurality of parts, and the divided heating coils are individually driven by a high-frequency power generation circuit to improve the donut-shaped temperature distribution. However, when cooking boiled food such as a pot filled with boiled juice, heat is transferred from the bottom of the heated object to the boiled juice, so the temperature distribution can be made uniform. When cooking fried foods using food, since the boiled juice is not filled, heat is easily dissipated in the outer periphery of the object to be heated, and the temperature near the outer periphery of the bottom of the object to be heated is lower than that in the center. There is a problem that uneven burning occurs.

  The present invention solves the above-described conventional problem, and there is no temperature difference between the outer peripheral portion and the central portion of the bottom surface of the heated object when cooking the fried food using a heated object such as a frying pan, that is, the temperature distribution is uniform. It is an object of the present invention to provide an electromagnetic cooker that can be made.

  In order to solve the above-described conventional problems, an electromagnetic cooker according to the present invention is provided with a heating means having two heating coils arranged substantially concentrically and substantially on the same plane and having different diameters, and disposed above the heating means. A high frequency power generation circuit that drives two heating coils to heat an object to be heated on the top plate, and a control circuit that controls the output power of the high frequency power generation circuit, During cooking of the stir-fried food, the heating coil arranged on the outside of the two heating coils is always driven, and the heating coil arranged on the inside is driven or stopped, or driven / stopped so as to make the bottom surface temperature of the object to be heated uniform. It has a stir fry mode.

  As a result, by using the stir-fry mode, the power input to the outer periphery of the bottom of the heated object is increased during cooking of the fried food such as a frying pan, that is, the outer periphery of the bottom of the heated object such as the frying pan. It becomes possible to concentrate the heating on the part, and it becomes possible to make the temperature distribution on the bottom surface of the heated object uniform and suppress uneven baking during cooking of the fried food using the heated object such as a frying pan.

  The electromagnetic cooker of the present invention has no temperature difference between the vicinity of the outer periphery and the center of the bottom surface of the heated object during cooking of the fried food using the heated object such as a frying pan, that is, it is possible to make the temperature distribution uniform. An electromagnetic cooker can be provided.

  According to a first aspect of the present invention, there is provided a heating means having two heating coils arranged substantially concentrically and substantially on the same plane and having different diameters, a top plate arranged above the heating means, and driving the two heating coils. A high frequency power generation circuit for heating an object to be heated on the top plate, and a control circuit for controlling the output power of the high frequency power generation circuit, the control circuit being outside of the two heating coils during cooking of the fried food The heating coil placed on the inside is always driven, and the heating coil placed inside is an electromagnetic cooker having a stir-fry mode that drives or stops, or drives / stops to make the bottom surface temperature of the object to be heated uniform. It is. As a result, by using the stir-fry mode, the power input to the outer periphery of the bottom of the heated object is increased during cooking of the fried food such as a frying pan, that is, the outer periphery of the bottom of the heated object such as the frying pan. It becomes possible to concentrate the heating on the part, and it becomes possible to make the temperature distribution on the bottom surface of the heated object uniform and suppress uneven baking during cooking of the fried food using the heated object such as a frying pan.

  In particular, the second invention includes, in the first invention, two high-frequency power generation circuits that individually drive each of the two heating coils, and a control circuit that controls output power of the two high-frequency power generation circuits. This makes it possible to increase the input power to the outer periphery of the bottom surface of the heated object during cooking of the fried food using the heated object such as a frying pan, that is, to concentrate the heating on the outer peripheral portion of the bottom surface of the heated object such as the frying pan. It becomes possible, and the temperature distribution on the bottom surface of the object to be heated can be made uniform at the time of cooking the fried food using the object to be heated such as a frying pan, and uneven baking can be suppressed. In addition, by using two high-frequency power generation circuits, it is possible to freely set the ratio of power to be applied to each of the two heating coils according to the state of the cooked food, improving the uniformity of temperature distribution and usability. be able to.

  According to a third aspect of the invention, in particular, in the first or second aspect of the invention, the control circuit concentrates the heating coil arranged on the outside of the two heating coils during cooking of the boiled food at the center of the article to be heated. The heating coil that is driven or stopped, or driven / stopped, has a boiled mode that always drives, so that when cooking a boiled food using a heated object such as a pan, it is applied to the outer periphery of the bottom of the heated object. It is possible to control the amount of power input, that is, to adjust the temperature distribution of the object to be heated, and the bottom surface temperature even when using objects to be heated with various outer diameters when cooking boiled food such as a pan The distribution can be made uniform and uneven burning can be suppressed.

  The fourth aspect of the invention is particularly suitable for the cooking contents of the third aspect of the invention, wherein the operation unit operated by the user is provided with a cooking mode key, and the user switches between the stir-fried mode and the boiled mode by the cooking mode key. Mode can be selected, and usability can be improved.

  In particular, in a fifth aspect of the present invention, in any one of the first to third aspects, the apparatus includes a temperature detection unit that is disposed below the object to be heated and detects the temperature of the object to be heated via the top plate. If the temperature of the heated object is lower than the specified temperature, the boiled food mode is automatically selected. If the temperature of the heated object is higher than the specified temperature, the fried food mode is automatically selected, so that the user does not have to manually select the cooking mode. In order to shift to an appropriate cooking mode, the usability can be improved.

  In particular, the sixth invention has display means for displaying that the user is standing in the fried food mode or the boiled food mode on the user's standing position side on the top plate surface in any one of the first to fifth inventions. By this, it becomes possible to confirm that the user is operating in a mode suitable for cooking contents, and usability can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1-5 has shown the electromagnetic cooker in Embodiment 1 of this invention.

  As shown in FIG. 1, the electromagnetic cooker 1 according to the present embodiment includes a high-frequency inverter circuit including a switching element that is turned on and off at a predetermined timing from a 200 V commercial power source that is a low-frequency AC power source via a rectifier circuit. The high frequency power generation circuit 2 for generating high frequency power of a predetermined frequency, the control circuit 3 for controlling the output power of the high frequency power generation circuit 2, and the substantially concentric and substantially the same plane for generating high frequency magnetic flux by the high frequency power. The first and second heating coils 4a and 4b (heating means 4 together) having different diameters and a hard glass top plate 5 disposed above the heating means 4 are provided.

  The high frequency power generation circuit 2 drives two heating coils 4a and 4b to heat an object to be heated 6 such as a pan or a frying pan on the top plate 5.

  The control circuit 3 always drives the heating coil 4b arranged outside of the two heating coils during cooking of the fried food, and the heating coil 4a arranged inside makes the bottom surface temperature of the article 6 to be heated uniform. It has a stir-fry mode in which it is driven or stopped, or driven / stopped at a predetermined timing. In addition, the control circuit 3 drives or stops, or drives / stops the heating coil 4b arranged on the outside of the two heating coils during the cooking of the boiled food so as to concentrate the heating on the central part of the article 6 to be heated. The heating coil 4a arranged inside has a boiled mode that is always driven.

  The electromagnetic cooker 1 in the present embodiment further includes an output power detection means 7 for detecting the output power of the high-frequency power generation circuit 2 and a temperature detection for detecting the bottom surface temperature of the article 6 to be heated via the top plate 5. Means 8: Cooking mode key 9 for selecting switching of cooking mode (stir fry mode and boiled mode) to the operation section operated by the user, fried food on the top plate 5 surface on the user's standing position side with good visibility It has the display means 10 which displays that it is in mode or boiled food mode.

  Furthermore, the high-frequency power generation circuit 2 includes first and second coil switching switching elements 11a and 11b (coil switching means 11 together), and the first coil switching switching element 11a is disposed inside. The first heating coil 4a is connected in parallel, and the second coil switching switching element 11b is connected in parallel with the second heating coil 4b disposed outside. The coil switching means 11 switches the driving / stopping state of each of the first or second heating coils 4a, 4b by turning on / off at a timing determined by the control circuit 3.

  In the present embodiment, the inner diameter of the first heating coil 4a is set to 60 mm and the outer diameter is set to 80 mm, and the inner diameter of the second heating coil 4b is set to 90 mm and the outer diameter is set to 180 mm. These diameters can be arbitrarily set. In the present embodiment, the first and second heating coils 4a and 4b are circular. However, other shapes such as a rectangle, an ellipse, or a polygon may be used. Furthermore, the first and second heating coils 4a and 4b can be formed in different shapes.

  In the present embodiment, one heating means 4 arranged on the lower surface of the top plate 5 has been described. However, as shown in the figure, even when there are a plurality of heating means 4, there is no problem and other heating means 4 can be used. It is also possible to give the means a similar function.

  The operation and action of the electromagnetic cooker 1 configured as described above will be described below.

  The user arranges a pan or a frying pan to be heated 6 through the top plate 5 so as to face the heating means 4 substantially. In this state, when the user selects the cooking mode with the cooking mode key 9 and presses the heating start button, the control circuit 3 drives the high frequency power generation circuit 2 to apply high frequency to the first and second heating coils 4a and 4b. Supply power. However, the cooking mode key 9 is effective even during heating, and the cooking mode can be switched during heating.

  Here, when the boiled food mode is selected at the time of heating, the 1st coil switching element 11a will always be in an OFF state, and will always drive the 1st heating coil 4a arranged inside. Further, the second coil switching element 11b is always turned on or off, or is turned on / off at a predetermined timing, so that the second heating coil 4b arranged outside is always driven or stopped, or at a predetermined timing. Drive / stop. The second heating coil 4b arranged outside is short-circuited and stopped when the second coil switching element 11b is turned on, whereas it is connected and driven in series with the first heating coil 4a when turned off.

  FIG. 2 shows the operation of each part. 2A is the output power of the first heating coil 4a disposed inside, FIG. 2B is the output power of the second heating coil 4b disposed outside, and FIG. 2C is the first coil switching. The operating state of the switching element 11a, (d) represents the operating state of the second coil switching switching element 11b.

  The period T1 shown in FIG. 2 is a period in which the second coil switching switching element 11b is turned on / off at a predetermined timing determined by the control circuit 3. During the period T1, the control circuit 3 changes the on-time or switching frequency of the second coil switching element 11b as in the periods T1a, T1b, and T1c shown in FIG. 2, that is, the second heating coil. It is possible to adjust the temperature distribution of the object to be heated 6 by controlling the driving / stopping state of 4b.

  Furthermore, since the second coil switching element 11b is always turned on during the period T2 shown in FIG. 2, only the first heating coil 4a disposed inside is driven, so that the central portion of the object 6 to be heated is driven. Heating can be concentrated in the vicinity of the center. In addition, since the second coil switching element 11b is always turned off during the period T3, the first heating coil 4a disposed inside and the second heating coil 4b disposed outside are both driven. The bottom surface of the object to be heated 6 can be heated entirely.

  The control circuit 3 appropriately selects and switches these operation states, thereby realizing a uniform temperature distribution of the object 6 to be heated as shown by a curve B1 in FIG. 3 (refer to Patent Document 1 for the curve A1 in FIG. 3). Represents the temperature distribution of a donut shape when using the above technology).

  In the present embodiment, at the start of heating, the operation state during the period T3 shown in FIG. 2, that is, the first and second heating coils 4a and 4b are simultaneously driven to heat the bottom surface of the object 6 to be heated entirely. The temperature of the article 6 to be heated is rapidly increased. Thereafter, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detecting means 8, the second is arranged outside like the periods T1a, T1b, T1c, and T2 shown in FIG. The bottom surface temperature of the object to be heated 6 is made uniform by adjusting the driving or stopping time of the heating coil 4b. This makes it possible to rapidly heat the object to be heated 6 at the start of heating, but during the period T3 at the start of heating, the temperature difference between the outer peripheral portion and the central portion of the bottom surface of the object to be heated 6 becomes large and uneven heating is caused. Occurs temporarily.

  Alternatively, the first heating coil 4a is always driven at the start of heating, and the second heating coil 4b is stopped at a predetermined cycle, as in the T1c period shown in FIG. It is possible to rapidly increase the bottom surface temperature of the article 6 to be heated so that the temperature difference between the outer peripheral portion and the central portion is reduced. After that, when the control circuit 3 detects that the temperature of the object to be heated 6 has risen from the detection result of the temperature detecting means 8, the second arranged on the outside as in the T1a, T1b, and T2 periods shown in FIG. By adjusting the driving or stopping time of the heating coil 4b, the bottom surface temperature of the object to be heated 6 is made uniform. Thereby, it becomes possible to suppress the temperature difference between the outer peripheral portion and the central portion of the bottom surface of the heated object 6 while rapidly heating the heated object 6 at the start of heating.

  In the present embodiment, the control circuit 3 controls the high frequency power generation circuit 2 in accordance with the detection contents of the output power detection means 7 so that the output power is constant, that is, as shown in FIGS. 2 (a) and 2 (b). As described above, the total output power of the first and second heating coils 4a and 4b is controlled to be 100%.

  The electromagnetic cooker 1 is equipped with the above-described boiled food cooking mode, thereby controlling the amount of electric power applied to the outer periphery of the bottom of the heated object 6 when cooking the heated object 6 such as a pan. It becomes possible to adjust the temperature distribution of the heated object 6, and even when using the heated object 6 of various outer diameters when cooking the boiled food using the heated object 6 such as a pan, the temperature distribution on the bottom surface is made uniform and burnt. Unevenness can be suppressed.

  When the fried food mode is selected at the time of heating, the second coil switching element 11b is always in the off state, and the second heating coil 4b arranged on the outside is always driven. Further, the first coil switching element 11a is always turned on or off, or is turned on / off at a predetermined timing, so that the first heating coil 4a disposed inside is always driven or stopped, or at a predetermined timing. Drive / stop. The first heating coil 4a disposed inside is short-circuited and stopped when the first coil switching element 11a is turned on, whereas it is connected and driven in series with the second heating coil 4b when turned off.

  FIG. 4 shows the operation of each part. 4A shows the output power of the first heating coil 4a arranged on the inner side, FIG. 4B shows the output power of the second heating coil 4b arranged on the outer side, and FIG. 4C shows the first coil switching switching. The operation state of the element 11a, (d) represents the operation state of the second coil switching element 11b.

  The period T4 shown in FIG. 4 is a period in which the first coil switching switching element 11a is turned on / off at a predetermined timing determined by the control circuit 3. During the period T4, the control circuit 3 changes the on-time or switching frequency of the first coil switching element 11a as in the periods T4a, T4b, and T4c shown in FIG. 4, that is, the first heating coil. It is possible to adjust the temperature distribution of the article 6 to be heated by controlling the driving / stopping state of 4a. Further, during the period T5 shown in FIG. 4, the first coil switching switching element 11a is always turned on, so that only the second heating coil 4b disposed on the outside is driven. Heating can be concentrated near the part. In addition, since the first coil switching element 11a is always turned off during the period T6, the first heating coil 4a arranged outside and the second heating coil 4b arranged outside are driven together. The bottom surface of the article to be heated 6 can be heated entirely.

  The control circuit 3 appropriately selects and switches these operating states, thereby realizing a uniform temperature distribution on the bottom surface of the heated object 6 as shown by a curve B2 in FIG. 5 (however, the curve A2 in FIG. 1 represents a donut-shaped temperature distribution when the technique of reference 1 is used).

  In the present embodiment, at the start of heating, the operating state of the T5 period shown in FIG. 4, that is, only the second heating coil 4 b arranged outside is driven to heat the outer peripheral portion of the bottom surface of the article 6 to be heated. The technical problem referred to in Patent Document 1 can be improved, such that the temperature of the outer peripheral portion of the article 6 to be heated tends to be lower than that of the central portion during cooking of the fried food. As a result, it is possible to suppress burning unevenness such as a partial burn. However, since only the outer peripheral portion of the article 6 to be heated is heated at the start of heating, it takes time to increase the temperature.

  Alternatively, the operation state during the period T6 shown in FIG. 4 at the start of heating, that is, the first and second heating coils 4a and 4b are simultaneously driven to heat the entire bottom surface of the article 6 to be heated, thereby rapidly covering the object. The temperature of the heated object 6 is raised. After that, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detecting means 8, the first arranged inside T4a, T4b, T4c, T5 shown in FIG. By adjusting the driving or stopping time of the heating coil 4a, the bottom surface temperature of the article 6 to be heated is made uniform. This makes it possible to rapidly heat the object to be heated 6 at the start of heating, but during the period T6 at the start of heating, a temperature difference occurs between the outer peripheral portion and the central portion of the bottom surface of the object to be heated 6 temporarily. Burning unevenness occurs.

  Alternatively, the second heating coil 4b is always driven at the start of heating, and the first heating coil 4a is stopped at a predetermined cycle, so that the bottom surface of the object to be heated 6 is stopped. It is possible to rapidly increase the bottom surface temperature of the article 6 to be heated so that the temperature difference between the outer peripheral portion and the central portion is reduced. After that, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detection means 8, the first heating arranged on the inner side as in the periods T4a, T4b, and T5 shown in FIG. By adjusting the driving or stopping time of the coil 4a, the bottom surface temperature of the article 6 to be heated is made uniform. Thereby, the uniform temperature distribution with little temperature difference of the outer peripheral part of the bottom face of the to-be-heated material 6 and a center part is realizable, heating the to-be-heated material 6 rapidly at the time of a heating start.

  In the present embodiment, the control circuit 3 controls the high-frequency power generation circuit 2 in accordance with the detection contents of the output power detection means 7 so that the output power is constant, that is, as shown in FIGS. 4 (a) and 4 (b). As described above, the total output power of the first and second heating coils 4a and 4b is controlled to be 100%.

  The electromagnetic cooker 1 increases the input power to the outer periphery of the bottom surface of the heated object 6 during cooking of the fried food using the heated object 6 such as a frying pan by installing the fried food cooking mode as described above. That is, heating can be concentrated on the outer peripheral portion of the bottom surface of the heated object 6 such as a frying pan, and the temperature distribution on the bottom surface of the heated object 6 is made uniform during cooking of the fried food using the heated object 6 such as a frying pan. Can be suppressed.

  Moreover, in this Embodiment, the cooking mode key 9 and the display means 10 are provided, a user can select a cooking mode manually with the cooking mode key 9, and the selected cooking mode is the display means 10. Is displayed on the top plate 5 surface with good visibility, so that the user can cook while confirming the cooking mode, improving usability.

  Further, in the present embodiment, temperature detecting means 8 for detecting the bottom surface temperature of the object to be heated 6 via the top plate 5 is provided, and the temperature of the object to be heated 6 is determined by the detection result of the temperature detecting means 8. Equipped with an automatic cooking mode that automatically sets the cooking mode to the boiled food mode when the temperature is below the predetermined temperature and automatically sets the cooking mode when the temperature of the heated object 6 is above the predetermined temperature. Has disappeared, improving usability. This automatic cooking mode can also be selected with the cooking mode key 9. However, when the automatic cooking mode is installed, the cooking mode key 9 can be removed to reduce the number of parts by always operating in the automatic mode.

  In the present embodiment, the output power ratio of each of the first and second heating coils 4a and 4b is determined by the turn number ratio and the diameter of the first and second heating coils 4a and 4b. By controlling the conduction time of each of the first and second heating coils 4a and 4b using the second coil switching elements 11a and 11b, the temperature distribution on the bottom surface of the object to be heated 6 can be changed. Thus, the bottom surface temperature of the object to be heated 6 is made uniform to suppress uneven baking.

(Embodiment 2)
6-10 has shown the electromagnetic cooker in embodiment of this invention. The same elements as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The difference from the first embodiment is that instead of the first and second coil switching elements 11a and 11b, the first and second heating coils 4a and 4b are individually driven as the high-frequency power generation circuit 2. First and second outputs that have first and second high-frequency power generation circuits 2a and 2b and detect output power of the first and second high-frequency power generation circuits 2a and 2b as output power detection means 7. It has power detection means 7a, 7b. Others are the same as in the first embodiment.

  The operation and action of the electromagnetic cooker 1 configured as described above will be described below.

  A pan or frying pan to be heated 6 is arranged on the top plate 5 by the user so as to face the heating means 4 substantially. In this state, when the user selects the cooking mode with the cooking mode key 9 and presses the heating start button, the control circuit 3 drives the high frequency power generation circuit 2 to apply high frequency to the first and second heating coils 4a and 4b. Supply power. However, the cooking mode key 9 is effective even during heating, and the cooking mode can be switched during heating.

  Here, when the boiled food mode is selected at the time of heating, the 1st high frequency electric power generation circuit 2a always drives the 1st heating coil 4a arrange | positioned inside. The second high frequency power generation circuit 2b always drives or stops the second heating coil 4b, or drives / stops at a predetermined timing.

  FIG. 7 shows the operation of each part. FIG. 7A shows the output power of the first heating coil 4a arranged inside, and FIG. 7B shows the output power of the second heating coil 4b arranged outside. The period T7 shown in FIG. 7 is a period in which the second high-frequency power generation circuit 2b drives / stops the second heating coil 4b at a predetermined timing determined by the control circuit 3. During the period T3, the control circuit 3 changes the drive time or the drive / stop cycle of the second high-frequency power generation circuit 2b as in the periods T7a, T7b, T7c shown in FIG. It is possible to adjust the temperature distribution of the article 6 to be heated by controlling the driving / stopping state of the heating coil 4b.

  Further, during the period T8 shown in FIG. 7, the second high-frequency power generation circuit 2b is always turned off, so that only the first heating coil 4a disposed on the inside is driven. Heat can be concentrated on the part (near the center). In addition, since the second high-frequency power generation circuit 2b is always turned on during the period T9, the first heating coil 4a disposed inside and the second heating coil 4b disposed outside are both driven. The bottom surface of the object to be heated 6 can be heated entirely. The control circuit 3 appropriately selects / switches these operating states, thereby realizing a uniform temperature distribution of the heated object 6 as shown by a curve B3 in FIG. 8 (refer to Patent Document 1 for the curve A3 in FIG. 8). Represents the temperature distribution of a donut shape when using the above technology).

  In the present embodiment, at the start of heating, the operating state of the period T9 shown in FIG. 7, that is, the first and second heating coils 4a and 4b are simultaneously driven to heat the entire bottom surface of the article 6 to be heated. The temperature of the article 6 to be heated is rapidly increased. Thereafter, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detecting means 8, the second is arranged outside like the periods T7a, T7b, T7c, and T8 shown in FIG. The bottom surface temperature of the object to be heated 6 is made uniform by adjusting the driving or stopping time of the heating coil 4b. This makes it possible to rapidly heat the object to be heated 6 at the start of heating, but during the period T9 at the start of heating, the temperature difference between the outer peripheral portion and the central portion of the bottom surface of the object to be heated 6 increases and uneven heating is caused. Occurs temporarily.

  Alternatively, the first heating coil 4a is always driven at the start of heating, and the second heating coil 4b is stopped at a predetermined cycle, as shown in the period T7c shown in FIG. It is possible to rapidly increase the bottom surface temperature of the article 6 to be heated so that the temperature difference between the outer peripheral portion and the central portion is reduced. Thereafter, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detecting means 8, the second heating arranged outside as in the periods T7a, T7b, T8 shown in FIG. By adjusting the driving or stopping time of the coil 4b, the bottom surface temperature of the article 6 to be heated is made uniform. Thereby, it becomes possible to suppress the temperature difference between the outer peripheral portion and the central portion of the bottom surface of the heated object 6 while rapidly heating the heated object 6 at the start of heating.

  In the present embodiment, the control circuit 3 controls the high-frequency power generation circuit 2 in accordance with the detection contents of the output power detection means 7 so that the output power is constant, that is, as shown in FIGS. 7 (a) and 7 (b). As described above, the total output power of the first and second heating coils 4a and 4b is controlled to be 100%.

  The electromagnetic cooker 1 controls the amount of electric power applied to the outer periphery of the bottom of the heated object during cooking of the boiled food using the heated object 6 such as a pan by installing the boiled food cooking mode as described above. It becomes possible to adjust the temperature distribution of the object 6, and even when using the heated object 6 of various outer diameters when cooking the boiled food using the heated object 6 such as a pan, the temperature distribution on the bottom surface is made uniform and uneven burning Can be suppressed.

  When the fried food mode is selected during heating, the second high-frequency power generation circuit 2b always drives the second heating coil 4b disposed on the outside. The first high-frequency power generation circuit 2a always drives or stops the first heating coil 4a disposed inside, or drives / stops at a predetermined timing.

  FIG. 9 shows the operation of each part. FIG. 9A shows the output power of the first heating coil 4a arranged inside, and FIG. 9B shows the output power of the second heating coil 4b arranged outside. The period T10 shown in FIG. 9 is a period in which the first high-frequency power generation circuit 2a is driven and stopped at a predetermined timing determined by the control circuit 3. During the period T10, the control circuit 3 changes the driving time or period of the first high-frequency power generation circuit 2a as in the periods T10a, T10b, and T10c shown in FIG. 9, that is, the first heating coil 4a. It is possible to adjust the temperature distribution of the article 6 to be heated by controlling the driving / stopping state.

  Further, during the period T11 shown in FIG. 9, the first high-frequency power generation circuit 2a is always turned off, so that only the second heating coil 4b disposed on the outside is driven. Heating can be concentrated near the part. In addition, since the first high-frequency power generation circuit 2a is always turned on during the T12 period, the first heating coil 4a arranged outside and the second heating coil 4b arranged outside are driven together. The bottom surface of the article to be heated 6 can be heated entirely.

  The control circuit 3 appropriately selects and switches these operating states, thereby realizing a uniform temperature distribution of the object to be heated 6 as shown by a curve B4 in FIG. 10 (however, refer to Patent Document 1 for the curve A4 in FIG. 10). Represents the temperature distribution of a donut shape when using the above technology).

  In the present embodiment, at the start of heating, the operating state of the period T11 shown in FIG. 9, that is, only the second heating coil 4b arranged outside is driven to heat the outer peripheral portion of the bottom surface of the article 6 to be heated. The technical problem referred to in Patent Document 1 can be improved, such that the temperature of the outer peripheral portion of the article 6 to be heated tends to be lower than that of the central portion during cooking of the fried food. As a result, it is possible to suppress burning unevenness such as a partial burn. However, since only the outer peripheral portion of the article 6 to be heated is heated at the start of heating, it takes time to increase the temperature.

  Alternatively, the operation state during the period T12 shown in FIG. 9 at the start of heating, that is, the first and second heating coils 4a and 4b are simultaneously driven to heat the entire bottom surface of the object 6 to be heated rapidly. The temperature of the heated object 6 is raised. After that, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detecting means 8, the first arranged inside T10a, T10b, T10c, T11 shown in FIG. By adjusting the driving or stopping time of the heating coil 4a, the bottom surface temperature of the article 6 to be heated is made uniform. This makes it possible to rapidly heat the object to be heated 6 at the start of heating, but during the period T12 at the start of heating, a temperature difference occurs between the outer peripheral portion and the central portion of the bottom surface of the object to be heated 6 to temporarily Burning unevenness occurs.

  Alternatively, the second heating coil 4b is always driven at the start of heating, as in the period T10c shown in FIG. 9, and the driving of the first heating coil 4a is stopped at a predetermined cycle. It is possible to rapidly increase the bottom surface temperature of the article 6 to be heated so that the temperature difference between the outer peripheral portion and the central portion is reduced. After that, when the control circuit 3 detects that the temperature of the article 6 to be heated has risen from the detection result of the temperature detection means 8, the first heating arranged on the inside as in the periods T10a, T10b, and T10 shown in FIG. By adjusting the driving or stopping time of the coil 4a, the bottom surface temperature of the article 6 to be heated is made uniform. Thereby, it becomes possible to suppress the temperature difference between the outer peripheral portion and the central portion of the bottom surface of the heated object 6 while rapidly heating the heated object 6 at the start of heating.

  In the present embodiment, the control circuit 3 controls the high-frequency power generation circuit 2 in accordance with the detection contents of the output power detection means 7 so that the output power is constant, that is, as shown in FIGS. 9 (a) and 9 (b). As described above, the total output power of the first and second heating coils 4a and 4b is controlled to be 100%.

  The electromagnetic cooker 1 is equipped with the above-described fried food cooking mode, thereby increasing the input power to the outer periphery of the bottom surface of the heated object 6 during cooking of the fried food such as a frying pan. Heating can be concentrated on the outer periphery of the bottom surface of the heated object 6 such as a frying pan, and the temperature distribution on the bottom surface of the heated object 6 is made uniform during cooking of the fried food using the heated object 6 such as a frying pan. Can be suppressed.

  In particular, in the present embodiment, unlike the first embodiment, the first and second heating coils 4a and 4b are individually driven by the first and second high-frequency power generation circuits 2a and 2b. The output power of each of the first and second heating coils 4a and 4b can be set to an arbitrary value, and the ratio of the power supplied to each of the first and second heating coils 4a and 4b can be freely set. Thus, the temperature distribution on the bottom surface of the object to be heated 6 can be more uniformly controlled.

  As described above, the electromagnetic cooker according to the present invention has no temperature difference between the outer peripheral portion and the central portion of the bottom surface of the heated object when cooking the fried food using the heated object such as a frying pan, that is, the temperature distribution is uniform. Therefore, it can be applied not only to ordinary homes and offices but also to professionals such as restaurants.

The block diagram of the electromagnetic cooker in Embodiment 1 of this invention Output state diagram of each part in boiled food mode in the same electromagnetic cooker Temperature distribution chart in boiled food mode in the same electromagnetic cooker Output state diagram of each part in the stir-fry mode in the same electromagnetic cooker Temperature distribution chart in stir-fried food mode in the same electromagnetic cooker The block diagram of the electromagnetic cooker in Embodiment 2 of this invention Output state diagram of each part in boiled food mode in the same electromagnetic cooker Temperature distribution chart in boiled food mode in the same electromagnetic cooker Output state diagram of each part in the stir-fry mode in the same electromagnetic cooker Temperature distribution chart in stir-fried food mode in the same electromagnetic cooker

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic cooker 2 High frequency power generation circuit 2a 1st high frequency power generation circuit 2b 2nd high frequency power generation circuit 3 Control circuit 4 Heating means 4a 1st heating coil 4b 2nd heating coil 5 Top plate 6 To-be-heated material 7 Output power detection means 8 Temperature detection means 9 Cooking mode key 10 Display means 11 Coil switching means

Claims (6)

A heating means having two heating coils arranged substantially concentrically and on the same plane and having different diameters, a top plate arranged above the heating means, and driving the two heating coils to cover the top plate. A high-frequency power generation circuit for heating a heated object and a control circuit for controlling the output power of the high-frequency power generation circuit, the control circuit being arranged outside the two heating coils during cooking of the fried food , And the heating coil disposed inside is an electromagnetic cooker having a fried food mode that is driven or stopped, or driven / stopped to equalize the bottom surface temperature of the object to be heated. The electromagnetic cooker according to claim 1, comprising two high-frequency power generation circuits that individually drive each of the two heating coils, and a control circuit that controls output power of the two high-frequency power generation circuits. The control circuit drives or stops, or drives / stops the heating coil arranged on the outside of the two heating coils during cooking of the boiled food to concentrate the heating on the central part of the object to be heated, and the heating coil arranged on the inside The electromagnetic cooker according to claim 1 or 2, wherein the coil has a boiled food mode that is always driven. The electromagnetic cooker according to claim 3, wherein a cooking mode key is provided in an operation unit operated by a user, and the fried food mode and the boiled food mode are switched by the cooking mode key. A temperature detection means is provided below the object to be heated and detects the temperature of the object to be heated via the top plate. If the temperature of the object to be heated is lower than a predetermined temperature, the boiled food mode is automatically set. The electromagnetic cooker according to any one of claims 1 to 3, wherein if the temperature is equal to or higher than a predetermined temperature, the fried food mode is automatically set. The electromagnetic cooker according to any one of claims 1 to 5, further comprising display means for displaying that the user is standing in the fried food mode or the boiled food mode on the top plate surface.