JP5523505B2 - Cooker - Google Patents

Description

  The present invention relates to a heating cooker that heats and cooks a heated object, and more particularly to a heating cooker that improves the cooking unevenness of the heated object and optimizes the cooking time.

  An IH (induction heating) type rice cooker, which is one of the existing cooking devices, induction heats a heating container detachably provided on the main body by a coil provided inside the main body, Has a function of heating an object to be heated (for example, rice and water) which is a content stored in the container. Heat cooking performed by such an IH rice cooker is roughly divided into (1) rice cooking process, (2) pre-boiling process, (3) boiling maintenance process, and (4) steaming process. And the IH rice cooker is controlling the electric power for heating so that the to-be-heated material may obtain the target temperature and time history in each step (1) to (4).

In addition, each process of (1)-(4) is demonstrated easily below.
(1) The rice cooking process is a preheating process that promotes water absorption at a relatively low temperature and under conditions where rice is less likely to gelatinize (starch gelatinization).
(2) The pre-boiling step is a step of boiling water to accelerate water absorption and gelatinization.
(3) Boiling maintenance process is a process which maintains a boiling state and advances gelatinization progress and moisture evaporation of rice.
(4) The steaming step is a step for eliminating uneven cooking by weakening input power after moisture evaporation is almost completed.

  Here, the heating control is to estimate the temperature of the contents using a thermistor provided outside the heating container in which the object to be heated is placed, an infrared sensor provided on the lid of the kettle to detect light in the infrared region, and the like. Thus, it is executed while feeding back to the power control in the above-described process and determining the switching timing of each process. However, even if the rice cooking process is performed at the same temperature and time, the water absorption speed and the gelatinization speed of the rice are usually different depending on the type and storage state of the rice. Therefore, in the heating control based on the temperature information, the texture of the cooked rice may vary.

  For example, rice that has a small amount of amylose component and is easily gelatinized tends to become soft because it is gelatinized at the beginning of cooking, has a large amount of water absorption, and enters the main cooking process in a swollen state. On the other hand, rice that has been dried tends to be hard and hard to gelatinize in the main cooking process because the rice surface absorbs water in the preheating process at the early stage of rice cooking, but the core part has little water absorption. Rice with low water absorption has a high water level at the start of boiling, and the surface layer tends to be soft because the temperature and moisture above the rice are high. On the other hand, rice with high water absorption tends to be opposite to rice with low water absorption.

  For this reason, IH rice cookers usually carry out heating control suitable for average rice, and as a result, heating and cooking time appropriate for rice varieties and storage conditions, rice cooking time, cooking It was difficult to carry out the rice cooking process that achieves a rising texture.

  By the way, in order to detect the components of rice and the state of gelatinization due to the type and storage state of rice, the rice taste evaluation apparatus irradiates the rice with light and estimates the taste based on the reflected light and transmitted light. Has been devised (for example, Patent Document 1). This cooked rice taste evaluation apparatus optically measures a plurality of elements (for example, appearance, hardness, stickiness) that affect the taste of cooked rice and evaluates the taste of the cooked rice.

  In addition, the bottom plate of the casing (inner container 2) is formed of a magnetic line transmission material made of transparent ceramic glass, and an infrared temperature sensor is installed at the center of the induction heating coil, and the temperature of the bottom plate of the casing is measured with this infrared temperature sensor. An IH rice cooker has been devised (see, for example, Patent Document 2). In this IH rice cooker, the heating container (rice cooker 1) is irradiated with infrared rays to measure the temperature outside the bottom of the heating container in a non-contact manner.

Japanese Patent Laid-Open No. 7-270312 (paragraph [0010] etc.) JP-A-7-277 (paragraphs [0036] to [0038] etc.)

  However, the cooked rice taste evaluation apparatus described in Patent Document 1 takes out cooked rice and detects this characteristic, and a heating container containing water and rice is incorporated in the rice cooker. However, there is no description about a configuration for obtaining rice information with high accuracy. That is, the device for evaluating the taste of cooked rice described in Patent Document 1 can easily compare the state of cooked rice for each cooked rice by evaluating cooked rice. It is not intended to achieve a heating, cooking time, and cooked texture that is appropriate for the condition.

  Moreover, as for the IH rice cooker described in Patent Document 2, the object whose temperature is detected by infrared rays is outside the bottom of the heating container, and does not accurately detect the state of rice or water inside the heating container. That is, the IH rice cooker described in Patent Document 2 is configured to perform heating control based on the measured temperature outside the bottom of the heating container, and heating that is not excessive or insufficient according to the rice species and storage state, It is not intended to realize the cooking time and texture after cooking.

  In any technique, it is not possible to detect the state of rice or water stored in the heating container and perform heating control based on this.

  The present invention has been made to solve the above problems, and detects the state of the object to be heated in a state where the object to be heated is contained in the heating container, and performs heating control based on this information. By doing, it aims at providing the cooking device which aimed at the improvement of the cooking nonuniformity of a to-be-heated material, and optimization of cooking time.

A cooking device according to the present invention includes a heating container partially or wholly composed of a member that transmits electromagnetic waves, a casing in which the heating container is detachably installed, a main body provided with the casing, and the main body An electromagnetic wave detection unit configured to detect an electromagnetic wave transmitted from or reflected by an object to be heated in the heating container, the heating unit heating the heating container , the electromagnetic wave irradiation unit irradiating the electromagnetic wave, and the electromagnetic wave irradiation unit. And control means for controlling power supplied to the heating means based on at least one change in intensity and frequency of the electromagnetic wave detected by the electromagnetic wave detection means, the heating means, the electromagnetic wave irradiation means And the electromagnetic wave detection means is located below the heating container installed in the casing, and the electromagnetic wave transmitting part of the heating container is placed above the heating container. To protrude, in which are located above than the portion facing to the heating means of the heating vessel.

  According to the cooking device of the present invention, it is possible to accurately detect the water absorption and gelatinization state of the object to be heated in the rice cooking process, and appropriate rice cooking control according to this can be performed. It becomes possible to cook rice.

It is a cross-sectional schematic diagram which shows roughly an example of a structure of the heating cooker which concerns on Embodiment 1 of this invention. The graph which showed typically an example of the change of the temperature during the cooking of the heating cooker which concerns on Embodiment 1 of this invention, the change of the heating control by a heating control means, and the change of the output of an electromagnetic wave detection means. It is. Another example of the change of the temperature during the cooking of the heating cooker which concerns on Embodiment 1 of this invention, the change of the heating control by a heating control means, and the change of the output of an electromagnetic wave detection means is shown typically. It is a graph. It is a cross-sectional schematic diagram which shows roughly an example of a structure of the heating cooker which concerns on Embodiment 2 of this invention. It is a cross-sectional schematic diagram which shows roughly an example of a structure of the heating cooker which concerns on Embodiment 3 of this invention. It is a cross-sectional schematic diagram which shows schematically another example of a structure of the heating cooker which concerns on Embodiment 3 of this invention. It is a cross-sectional schematic diagram which shows roughly an example of a structure of the heating cooker which concerns on Embodiment 4 of this invention.

  Hereinafter, embodiments of a heating cooker according to the present invention will be described with reference to the drawings. Moreover, in embodiment, it demonstrates supposing that the heating cooker which concerns on this invention is an IH type rice cooker. It should be noted that the present invention is not limited by the embodiments described below, and it does not depend on the illustrated structure as long as the effects described above are obtained. Moreover, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

Embodiment 1 FIG.
FIG. 1 is a schematic cross-sectional view schematically showing an example of the configuration of the heating cooker 100 according to Embodiment 1 of the present invention. Based on FIG. 1, the structure of the heating cooker 100 is demonstrated. FIG. 1 also shows a diagram in which a portion surrounded by a broken line is schematically enlarged. The heating cooker 100 cooks the object to be heated by heating the heating container 4 containing the object to be heated (food such as rice and water) with the heating coil 5. The heating coil 5 corresponds to the heating device of the present invention.

  As shown in FIG. 1, a heating cooker 100 includes a substantially bottomed cylindrical main body 1, a casing 2 provided inside the main body 1, and a substantially central portion of the bottom portion protruding upward, and an upper portion of the main body 1. And a lid 3 attached to the main body 1 so that the opening can be opened and closed. The casing 2 has an opening on the upper surface, and a bottomed cylindrical heating container 4 containing a magnetic metal that generates heat by induction heating is detachably accommodated. In the heating container 4, the substantially central portion of the bottom portion protrudes upward in accordance with the shape of the casing 2. A window 45 that transmits electromagnetic waves is provided in this portion. The inner wall of the heating container 4 is provided with a water level memory (for example, a water level memory 42 with a minimum rice cooking amount) for use as a measure of the amount of water when the user puts water during cooking.

  A heating coil 5 that induction-heats the heating container 4 by controlling energization is provided at a portion of the main body 1 that is opposed to the substantially bottom surface of the heating container 4 below the casing 2. The main body 1 is provided with a heating control means 6 for controlling energization to the heating coil 5, and is connected to the heating coil 5. Further, the main body 1 is provided with an electromagnetic wave source 7 which is an electromagnetic wave irradiation means for irradiating an electromagnetic wave, and an electromagnetic wave detection means 8 on which the electromagnetic wave is incident. The electromagnetic wave source 7 and the electromagnetic wave detecting means 8 are disposed outside a portion where the bottom portion of the casing 2 of the main body 1 protrudes upward (hereinafter referred to as a protruding portion 2a). A substantially disk-shaped inner lid capable of sealing the opening of the heating container 4 is detachably attached to the inside of the lid 3 (the side covering the opening of the heating container 4).

The electromagnetic wave source 7 may be configured by an apparatus that can irradiate an electromagnetic wave including a wave number of 5000 to 500 cm ⁻¹ . Further, in the cooking device 100, after a part of the electromagnetic wave irradiated from the electromagnetic wave source 7 is absorbed and changed by the heated object accommodated in the heating container 4, the electromagnetic wave is detected again through the window 45. An electromagnetic wave path 10 leading to the means 8 is formed (paths indicated by arrows A and B).

The operation of the electromagnetic wave source 7 and the electromagnetic wave detection means 8 will be described.
The electromagnetic wave irradiated from the electromagnetic wave source 7 passes through the upper surface of the bottom of the casing 2 and the window 45 of the heating container 4 and reaches the rice grains 43 accommodated in the heating container 4 (arrow A shown in FIG. 1). A part of the electromagnetic wave transmitted through the inside of the rice grain 43 or reflected by the surface of the rice grain 43 is again transmitted through the window 45 of the heating container 4 and the bottom upper surface of the casing 2 and enters the electromagnetic wave detecting means 8 ( Arrow B shown in FIG. When electromagnetic waves are transmitted through the inside of the rice grain 43 or reflected by the surface of the rice grain 43, at least one of intensity and frequency changes. The electromagnetic wave incident on the electromagnetic wave detection means 8 is converted into an output signal by the electromagnetic wave detection means 8.

  The output signal converted by the electromagnetic wave detection means 8 is transmitted to a microcomputer (control means) not shown. A heating control sequence is stored in advance in the microcomputer. The microcomputer that has received the output signal from the electromagnetic wave detection means 8 outputs a control signal to the heating control means 6 based on the previously stored heating control sequence. The heating control means 6 that has received the control signal from the microcomputer performs the rice cooking process based on the received control signal.

As the electromagnetic wave source 7, a device that generates and radiates part or all of energy ranging from infrared rays to millimeter waves can be used. Among them, 1000 cm ^-1 and,, 5000 cm ^-1 near the infrared, it is known that absorption of electromagnetic waves US is changed according to gelatinization degree, generates the infrared, using a light source which emits as an electromagnetic wave source 7 It is desirable. Further, it is known that the near infrared region changes depending on the moisture content. The millimeter wave region is known to change according to the mobility of water molecules. In these electromagnetic wave generators, in order to irradiate electromagnetic waves in a specific region, it is desirable to attach a material that transmits only the electromagnetic waves in the specific region as a bandpass filter to the electromagnetic wave source generating portion. Further, when the wavelength region of the electromagnetic wave generated from the electromagnetic wave source 7 is wide, a band pass filter that transmits at least two types of wavelength regions is provided, and a mechanism that irradiates a plurality of wavelength regions with one electromagnetic wave source is provided. Also good.

  Similarly, for the electromagnetic wave detection means 8, an apparatus is selected that can obtain an energy region having a sufficient correlation with the target water absorption rate and gelatinization degree with a necessary resolution. For example, as the electromagnetic wave detection means 8, it is preferable to use one provided with a mechanism for detecting electromagnetic wave intensity in at least two or more wavelength regions. The electromagnetic wave detection means 8 is also provided with a band pass filter that passes one or more specific wavelengths as in the case of the electromagnetic wave source 7, or is irradiated with electromagnetic waves intermittently, and a lock-in amplifier is used. It is desirable to improve detection accuracy by using a mechanism that amplifies a detection signal component synchronized with the timing of electromagnetic wave irradiation.

  For the window 45 that is an electromagnetic wave transmitting portion, non-metallic glass or ceramic, or a resin having heat resistance of at least 100 degrees or more can be used. Between the heating container 4 and the window 45, a gap due to the difference in thermal expansion between the two materials is generated, so that water leakage does not occur. It is better to take measures such as welding the material and sealing.

  Next, the output of the electromagnetic wave detection means 8 of the cooking device 100 and the heating control operation of the heating control means 6 will be described in more detail with reference to FIG. FIG. 2 is a graph schematically showing an example of a change in temperature during cooking by the heating cooker 100, a change in electric power by the heating control means 6, and a change in the output of the electromagnetic wave detection means 8. Here, it is assumed that the electromagnetic wave to be irradiated is in an energy region having a high correlation with the gelatinization of rice, and that the output of the electromagnetic wave detection means 8 increases as the degree of gelatinization progresses. The target may be the moisture content of rice, and an energy region having a high correlation may be used, or the numerical value may depend on the circuit configuration of the apparatus.

  Before operating the cooking device 100, the user first sets the heating container 4 containing a predetermined amount of rice and water corresponding to the amount of rice in the heating container 4 in the casing 2 of the main body 1. And a user closes the lid | cover 3, selects a desired rice cooking process from a rice cooking menu with the operation button abbreviate | omitting illustration, and presses the rice cooking start button which is one of the operation buttons. The cooking device 100 starts the rice cooking process by pressing the rice cooking start button by the user. Here, the description will be made assuming that the standard rice cooking process is selected.

  When the rice cooking process is started, the microcomputer of the heating cooker 100 first starts the preheating process. In the preheating process, the heating control means 6 energizes the heating coil 5 to adjust the heating so that the bottom temperature detected by a thermistor (not shown) becomes T1. Here, the electric power W <b> 1 is intermittently supplied to the heating coil 5 based on a signal from the heating control means 6. Thereby, the bottom temperature rises to T1, and this T1 is maintained. At this time, the output of the electromagnetic wave detection means 8 changes according to the degree of gelatinization of rice. The microcomputer determines whether or not the output of the electromagnetic wave detection means 8 has exceeded a predetermined S1, and when the output has exceeded a predetermined S1, moves to the next main cooking process.

  Here, in the main cooking step, the electric power W <b> 2 is input to the heating coil 5 by the heating control means 6. The microcomputer determines whether or not the output of the electromagnetic wave detection means 8 has reached a predetermined S2, and continues the power W2 to the heating coil 5 by the heating control means 6 until the output of the electromagnetic wave detection means 8 reaches the predetermined S2. Let me throw in. Then, after the output of the electromagnetic wave detection means 8 reaches a predetermined S2, the microcomputer causes the heating control means 6 to intermittently input the power W3 to the heating coil 5. Next, the microcomputer determines whether or not the output of the electromagnetic wave detection means 8 has reached a predetermined S3. After the output of the electromagnetic wave detection means 8 has reached a predetermined S3, the heating control means 6 again causes the power W1 to be intermittent. Is put into the heating coil 5.

  Thus, in the heating cooker 100, the change timing of the rice cooking process and the heating control output, the power in the heating control, the power ON / OFF ratio, and the like are changed based on the output of the electromagnetic wave detection means 8. . By doing so, according to the heating cooker 100, it is possible to carry out heating that is not excessive or insufficient according to the degree of gelatinization of the rice, so that poor texture such as hardening due to insufficient cooking or loss of stickiness due to excessive water absorption. This makes it possible to cook delicious rice.

  In addition, although the change timing of a rice cooking process or a heating control output is determined only by the output of the electromagnetic wave detection means 8, you may use together the determination based on time or a separate temperature detection result. Moreover, you may determine based on the output variation | change_quantity and output integrated value which examined the correlation with the moisture content of rice, and the gelatinization degree instead of the absolute value of electromagnetic wave detection output. Furthermore, for example, as shown in FIG. 3, a method of changing the heating control by combining the time and the detection output may be adopted.

  FIG. 3 is a graph schematically showing another example of a change in temperature during cooking by the cooking device 100, a change in heating control by the heating control means 6, and a change in output of the electromagnetic wave detection means 8. It is. That is, as shown in FIG. 3, when the time t1 at which the output of the electromagnetic wave detection means 8 reaches S1 is shorter than the preset tx, the main cooking process with the preset power W2 is started, When the time t1 is longer than the preset tx, the main cooking configuration is performed with the electric power W2 ′ larger than the electric power W2. Thereafter, after the output of the electromagnetic wave detection means 8 reaches S2, the control shifts to heating control with the power W3.

  In addition, the case where t1 is short has shown that the gelatinization of rice is quick, and it exists in the tendency which water absorption is quicker and softer than usual (tx setting). On the other hand, the case where t1 is slow indicates that the gelatinization of rice tends to be slow, and the heating power at the start of the main cooking process is increased and heated quickly to increase the time during which the rice is in the high temperature range. By this, gelatinization can be accelerated | stimulated, without extending the total rice cooking time. That is, in the heating cooker 100, when it is determined that water absorption or gelatinization is fast according to the detected progress of water absorption or gelatinization (for example, when t2 ′ reaching S2 is determined to be earlier than a predetermined time). Set a large amount of power in the boiling maintenance process after reaching boiling (for example, lengthening the maintenance time of the electric power W2), accelerating moisture evaporation in the boiling maintenance process and preventing excessive water absorption of rice, Control to shorten and prevent excessive softening. In the figure, the maximum power when the power is turned on is changed according to the output of the electromagnetic wave detection means 8, but a more delicious texture can be obtained or the cooking time can be shortened as the gelatinization progresses. However, the present invention is not limited to this as long as a result corresponding to the purpose to be obtained is obtained, and the ON / OFF cycle may be changed, continuous energization may be performed, or more complicated power control may be performed.

Next, structural features for improving the accuracy of the electromagnetic wave detection means 8 will be described.
Since the temperature of the inner wall surface of the heating container 4 in the vicinity of the heating coil 5 rises before the temperature inside the heating container 4 rises and the boiling starts, boiling bubbles are likely to be generated (see the boiling bubbles 44 shown in FIG. 1). ). Boiling bubbles cause fluctuations in detection output due to a decrease in electromagnetic wave intensity or scattering due to scattering of electromagnetic waves, and as a result, it may be difficult to determine whether the target detection output has been reached.

  Therefore, in the heating cooker 100, the electromagnetic wave source 7 and the electromagnetic wave detection means 8 are installed on the protruding portion 2a of the casing 2, as shown in FIG. As a result, boiling starts at a substantially bottom surface of the heating container 4 facing the installation portion of the heating coil 5, and even if bubbles are generated, the electromagnetic wave source 7 and the electromagnetic wave detection means 8 are installed from the position where the boiling bubbles 44 are generated. Can be far away. That is, since the window 45 is installed at a predetermined interval from the position where the boiling bubble 44 is generated, the boiling bubble 44 can be moved away from the window 45. In addition, since the window 45 is installed above the position where the boiling bubble 44 is generated, the boiling bubble 44 desorbed from the bottom surface of the heating container 4 includes the window 45, and the electromagnetic wave detection means from the electromagnetic wave source 7. A few states can be formed in the electromagnetic wave path 10 leading to 8.

  As described above, the heating cooker 100 is less susceptible to the boiling bubbles 44 by installing the electromagnetic wave source 7 and the electromagnetic wave detecting means 8 on the protruding portion 2a of the casing 2, and the electromagnetic wave radiated from the electromagnetic wave source 7 is emitted. The detection accuracy of the electromagnetic wave detection means 8 can be greatly increased. Therefore, in the heating cooker 100, the determination accuracy by the microcomputer using electromagnetic waves can be greatly increased. 1 shows an example in which the electromagnetic wave source 7 and the electromagnetic wave detection means 8 are installed on the top surface of the protruding portion 2a of the casing 2, the electromagnetic wave source 7 and the electromagnetic wave detecting means 8 are connected to the protruding portion 2a. You may install in the side. Or the protrusion part 2a of the casing 2 may be provided in the side surface of the heating container 4, and the electromagnetic wave source 7 and the electromagnetic wave detection means 8 may be installed here. In this case, it is necessary to provide a protrusion on the side surface, not the bottom surface of the heating container 4.

  Further, as a structural feature for improving accuracy, in order to reliably detect the state of the rice grain 43, the electromagnetic wave is reliably irradiated to the rice, and the electromagnetic wave transmitted or reflected through the rice is transmitted to the electromagnetic wave detecting means 8. It is desirable to shorten the electromagnetic wave path 10 to reach. For this reason, it is good to install the electromagnetic wave source 7 and the electromagnetic wave detection means 8 in the protrusion part 2a so that the window 45 may be located below the rice upper surface position 41 of minimum rice cooking amount. In addition, when the state of the rice cooking liquid that is eluted from the rice grains 43 and becomes cloudy is detected instead of the rice grains 43, the electromagnetic wave detection means 8 is positioned below the water level memory 42 of at least the minimum rice cooking amount. It is good to install like this.

  As mentioned above, according to the heating cooker 100, since the water absorption and gelatinization state of the rice in a rice cooking process can be detected accurately, and appropriate rice cooking control according to this can be implemented, predetermined food texture You can cook delicious rice and rice with less uneven cooking. Moreover, according to the heating cooker 100, in the case of the rice with quick water absorption and gelatinization, by performing appropriate control, rice cooking time is shortened and it becomes an energy-saving thing by that. Moreover, based on the same design idea, it contributes to the cooking performance improvement with the cooking appliance which cooks rice cookers other than IH type, and boiled food.

Embodiment 2. FIG.
FIG. 4 is a schematic cross-sectional view schematically showing an example of the configuration of a heating cooker 100A according to Embodiment 2 of the present invention. Based on FIG. 4, the structure of the heating cooker 100A is demonstrated. FIG. 4 also shows a schematic enlarged view of a portion surrounded by a broken line. This heating cooker 100 </ b> A is similar to the heating cooker 100 according to the first embodiment, by heating the heating container 4 containing the heated object (food such as rice or water) with the heating coil 5. It is something to cook. In the second embodiment, differences from the first embodiment will be mainly described, and the same parts as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

  As shown in FIG. 4, in the heating cooker 100 </ b> A, the electromagnetic wave source 7 and the electromagnetic wave detection means 8 are provided at positions away from the bottom surface of the heating container 4, and light irradiation is performed via a double cylindrical optical fiber 50. Reflected light detection is performed. The optical fiber 50 includes an inner fiber 51 and an outer fiber 52 as shown in an enlarged view in FIG. One end of the inner fiber 51 is connected to the electromagnetic wave source 7, and the other end is connected to the protruding portion 2 a of the casing 2, and the electromagnetic wave from the electromagnetic wave source 7 passes through the lumen of the inner fiber 51 to the bottom surface of the heating container 4. Radiated towards. Further, one end of the outer fiber 52 is connected to the protruding portion 2 a of the casing 2 and the other end is connected to the electromagnetic wave detecting means 8, and electromagnetic waves transmitted through the rice grain 43 or reflected from the surface of the rice grain 43 are externally transmitted. It enters the electromagnetic wave detection means 8 through the lumen of the fiber 52.

  By adopting such a form, not only the same effect as the cooking device 100 according to the first embodiment is obtained, but also the electromagnetic wave source 7 and the electromagnetic wave detection means 8 are heated, that is, from the heating container 4. It can be separated, and destabilization of these devices due to temperature can be suppressed, and an increase in the height of the entire main body can also be suppressed. The length and diameter of the optical fiber 50 are not particularly limited, and the size and shape of the cooking device 100A, the size and shape of the casing 2, the size and shape of the heating container 4, the electromagnetic wave source 7 and the electromagnetic wave detection means 8 What is necessary is just to determine based on a magnitude | size, a shape, etc.

Embodiment 3 FIG.
FIG. 5 is a schematic cross-sectional view schematically showing an example of the configuration of a heating cooker 100B according to Embodiment 3 of the present invention. Based on FIG. 5, the structure of the heating cooker 100B is demonstrated. FIG. 5 also shows a diagram in which a portion surrounded by a broken line is schematically enlarged. This heating cooker 100B, like the heating cooker 100 according to the first embodiment, heats the heating container 4 containing the heated object (food such as rice and water) with the heating coil 5 to be heated. It is something to cook. In the third embodiment, differences from the first embodiment will be mainly described, and the same parts as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

  As shown in FIG. 5, in the heating cooker 100 </ b> B, the entire heating container 4 is made of an electromagnetic wave transmissive material, such as glass or ceramic. In general, a conductive material such as metal or charcoal that constitutes the heating container 4 and that can be heated by induction does not transmit electromagnetic waves. Therefore, in the first and second embodiments, the window 45 is provided in the heating container 4, but in the third embodiment, the heating container 4 itself is formed of an electromagnetic wave transmissive material. In this case, since the heating container 4 is not induction-heated, in the heating cooker 100B, for example, a donut-shaped stainless steel plate is installed as the induction heating member 9 in the heating container 4. Thereby, this induction heating member 9 is heated by the heating coil 5, and the whole cooking process can be implemented.

  By adopting such a form, not only the effect similar to that of the heating cooker 100 according to Embodiment 1 is exhibited, but it is not necessary to provide the heating container 4 with a window 45 that transmits electromagnetic waves, and the formation of the window 45 is not necessary. Necessary sealing or the like can be eliminated. The constituent material of the heating container 4 is not limited to glass or ceramic, and a material that can transmit electromagnetic waves and has excellent heat resistance may be selected. Further, the material and shape of the induction heating member 9 are not particularly limited, and may be made of a material that can be induction heated by the heating coil 5.

  The starch eluted from the rice grains 43 during cooking, not the rice grains 43 themselves, adheres to the surface layer of the cooked rice to form a so-called Oneba layer. Using this Oneva layer, it may be possible to detect a state in which water becomes cloudy or to determine the gelatinization state of the eluted starch and to estimate the cooked rice based on these (in FIG. 6). (See heating cooker 100B shown).

  FIG. 6 is a schematic cross-sectional view schematically illustrating another example of the configuration of the heating cooker 100B. As shown in FIG. 6, in the heating cooker 100 </ b> B, a protrusion 9 a having a mesh formed at the center of the induction heating member 9 is provided. The mesh is formed in such a size that the rice grains 43 cannot pass through but the rice cooking liquid (water or water in which starch is dissolved) can pass through. And both the heating container 4 and the bottom face of the casing 2 are formed flat.

  By setting it as such a form, it not only has the effect similar to the heating cooker 100 which concerns on Embodiment 1, but in the space (space 11) between the to-be-induced heating member 9 and the bottom face of the heating container 4 Only rice cooking liquid exists, and rice cooking control can be carried out according to the electromagnetic wave absorption state of this part. The boiling bubbles 44 are generated when the surface of the induction heating member 9 is heated. Therefore, the boiling bubbles 44 are not easily generated in the space 11 and are not affected by the surface shape of the rice grains 43, so that stable detection is possible. .

Embodiment 4 FIG.
FIG. 7 is a schematic cross-sectional view schematically showing an example of the configuration of a heating cooker 100C according to Embodiment 4 of the present invention. Based on FIG. 7, the structure of the heating cooker 100C is demonstrated. FIG. 7 also shows a diagram in which a portion surrounded by a broken line is schematically enlarged. This heating cooker 100C, like the heating cooker 100 according to the first embodiment, heats the heating container 4 containing the heated object (food such as rice and water) by the heating coil 5 to be heated. It is something to cook. In the fourth embodiment, differences from the first embodiment will be mainly described, and the same parts as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted.

  As shown in FIG. 7, in the heating cooker 100C, the electromagnetic wave source 7 and the electromagnetic wave detecting means 8 are both measured at two or more positions, one of which is the temperature inside the heating container 4 from the reflected wave inside the heating container 4. The other detects the reflected wave from the rice grain 43.

  Thus, by detecting the temperature of the heating container 4 and the gelatinization state of the rice, in addition to the same effects as those of the heating cooker 100 according to the first embodiment, finer control can be performed. That is, while the pot inner wall temperature is high and the rice grain temperature is low, the output of the heating coil 5 is increased, but if this difference is reduced, it is possible to prevent scorching or excessive water absorption by reducing the power. Although not shown, generally, a thermistor that contacts the outside of the heating container 4 or a means for measuring the temperature with an infrared sensor is used, but this can be omitted and the number of parts can be reduced.

  In the first to fourth embodiments, the state in which the microcomputer and the heating control means 6 are separate has been described as an example. However, the heating control means 6 may be provided as one function of the microcomputer. Moreover, although this invention was each demonstrated in Embodiment 1-4, you may make it comprise a heating cooker combining the characteristic matter of each embodiment. For example, the content that two or more positions are to be measured as described in the fourth embodiment may be applied to a heating cooker to which the optical fiber 50 as described in the second embodiment is applied.

  DESCRIPTION OF SYMBOLS 1 Main body, 2 Casing, 2a Protruding part, 3 Lid, 4 Heating container, 5 Heating coil, 6 Heating control means, 7 Electromagnetic wave source, 8 Electromagnetic wave detection means, 9 Induction heating member, 9a Protruding part, 10 Electromagnetic path, 11 Space, 41 Rice top surface position of minimum rice cooking amount, 42 Water level memory of minimum rice cooking amount, 43 Rice grain, 44 Boiling foam, 45 Window, 50 Optical fiber, 51 Inner fiber, 52 Outer fiber, 100 Heating cooker, 100A Heating cooker , 100B cooker, 100C cooker.

Claims (13)

A heating container partially or entirely composed of a member that transmits electromagnetic waves;
A casing in which the heating container is detachably installed;
A body provided with the casing;
A heating means provided on the main body for heating the heating container;
Electromagnetic wave irradiation means for irradiating electromagnetic waves;
An electromagnetic wave detecting means for detecting an electromagnetic wave irradiated from the electromagnetic wave irradiation means and transmitted or reflected by an object to be heated in the heating container;
Control means for controlling electric power supplied to the heating means based on at least one change in intensity and frequency of the electromagnetic wave detected by the electromagnetic wave detection means,
The heating means, the electromagnetic wave irradiation means, and the electromagnetic wave detection means are located below the heating container installed in the casing.
An electromagnetic wave transmitting portion of the heating container is protruded upward so that the heating container is positioned above a portion of the heating container facing the heating means. The heating means, the electromagnetic wave irradiation means, and the electromagnetic wave detection means are located below the heating container installed in the casing.
The heating cooker according to claim 1 , wherein the electromagnetic wave transmitting portion of the heating container is positioned at least below a water level required for the minimum amount of rice cooking. The electromagnetic wave irradiation means includes
It is comprised with the apparatus which can irradiate the electromagnetic waves containing the wave number of 5000-500cm < ^-1 >. The heating cooker of Claim 1 or Claim 2 characterized by the above-mentioned. In the body,
After a part of the electromagnetic wave irradiated from the electromagnetic wave irradiation means passes through the object to be heated in the heating container, an electromagnetic wave path is formed which passes again through the electromagnetic wave transmission part of the heating container and reaches the electromagnetic wave detection means. The cooking device according to any one of claims 1 to 3 , wherein the cooking device is a cooking device. The electromagnetic wave detecting means is
The cooking device according to any one of claims 1 to 4 , further comprising a mechanism for detecting electromagnetic wave intensities in at least two types of wavelength regions. The electromagnetic wave detecting means is
The heating cooker according to any one of claims 1 to 5 , further comprising a mechanism for detecting electromagnetic waves from two or more parts including at least a part of an inner wall surface of the heating container. . The electromagnetic wave irradiation means and the electromagnetic wave detection means are:
It is comprised so that electromagnetic waves may be irradiated and detected through an optical fiber. The heating cooker as described in any one of Claims 1-6 characterized by the above-mentioned. The control means includes
When the electromagnetic wave detected by the electromagnetic wave detection means reaches a predetermined value set in advance,
The cooking device according to any one of claims 1 to 7 , wherein the electric power supplied to the heating means is changed to shift from the preheating step to the main cooking step. The control means includes
The cooking device according to claim 8 , wherein the electric power supplied to the heating unit is controlled based on the electromagnetic wave detected by the electromagnetic wave detection unit to adjust the time until boiling. After the preheating step, when the change of the electromagnetic wave detected by the electromagnetic wave detection means in the middle of the boiling is larger than a predetermined amount, the electric power supplied to the heating means is increased until the boiling is reached. The cooking device according to claim 9 . The power to be input to the heating unit after the boiling detection is increased when the change in the electromagnetic wave detected by the electromagnetic wave detection unit in the middle of the preheating step is larger than a predetermined amount. 9. The heating cooker according to 9 . In what formed the circuit so that the change of the electromagnetic wave detected by the electromagnetic wave detection means becomes larger as the degree of gelatinization of the heated object proceeds,
The control means includes
When it is determined that the time to reach boiling detection by the electromagnetic wave detected by the electromagnetic wave detection means is shorter than the preset time, the main cooking process is started with preset power,
The main cooking process is started with a power larger than a preset power when it is determined that the time to reach boiling detection by the electromagnetic wave detected by the electromagnetic wave detection means is longer than a preset time. Item 12. The cooking device according to any one of Items 8 to 11 . The control means includes
The power applied to the heating unit is changed to at least two levels based on the electromagnetic wave detected by the electromagnetic wave detection unit, and the ratio of the time for maintaining these different powers is changed. heating cooker according to any one of claims 8-12.

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