JP5074972B2 - Temperature detection device for cooking device - Google Patents

Description

  The present invention provides a heating means for heating a cooking container, an infrared intensity detection means for detecting an infrared intensity of infrared rays emitted from the cooking container, and the infrared intensity detected by the infrared intensity detection means. The present invention relates to a temperature detection device for a heating cooker comprising temperature detection means for detecting the temperature of the cooking container.

  Such a temperature detection device for a cooking device is applied to a cooking device such as a gas stove equipped with a gas burner as a heating means for heating a cooking container, and conventionally includes a thermopile for detecting infrared intensity or the like. An infrared intensity detecting means is provided, the infrared intensity emitted from the cooking container heated by the heating means is detected by the infrared intensity detecting means, and the temperature of the cooking container is detected based on the detection result. There was what it did (for example, refer patent document 1) (henceforth the 1st prior art example).

  Further, as another conventional example, the infrared intensity detecting means is configured to detect the infrared intensity in two different wavelength ranges separately, and the temperature detecting means is a ratio of the infrared intensity in the two different wavelength ranges. And the temperature of the cooking container is detected from the correlation between the infrared intensity ratio and the previously stored infrared intensity ratio and the temperature (see, for example, Patent Document 2). (Hereinafter referred to as the second conventional example).

Japanese Patent Publication No. 7-43122 JP 2002-340339 A

  In general, since an object emits infrared rays having an intensity corresponding to its temperature, it is possible to measure the intensity of infrared rays emitted from the object and detect the temperature of the object based on the infrared intensity. Then, the temperature of the cooking container is detected using such characteristics.

  However, when the emissivity of the substance is different, the infrared intensity emitted is different even if the temperature is the same. As a cooking container used in actual cooking, cooking made of various substances is possible. In the first conventional example, the difference in emissivity is not taken into consideration, and the infrared ray intensity is detected on the assumption that the emissivity of the cooking container does not change greatly. The temperature cannot be accurately detected depending on the cooking container to be used.

  And as a thing for detecting temperature in the state which reduced the error resulting from the emissivity difference of the cooking container as mentioned above, the temperature detection apparatus for heating cookers as described in a 2nd prior art example Has been proposed. When the explanation is added, the correlation between the ratio of the infrared intensity in two different wavelength ranges detected by the infrared intensity detecting means and the temperature of the cooking container radiating infrared rays is different in the material of the cooking container. In other words, on the premise that the characteristics are almost the same regardless of the difference in emissivity of the cooking container, the infrared intensity in the two wavelength regions is detected by the infrared intensity detecting means for the cooking container to be temperature measured. The temperature of the cooking container is detected from the measurement result and the correlation between the infrared intensity ratio and the temperature as described above.

  The present application aims to detect the temperature of the cooking container regardless of the difference in emissivity of the cooking container as described above, as in the second conventional example. It is in providing the temperature detection apparatus for cooking-by-heating equipment which can detect the temperature of a cooking container by estimating the emissivity of a cooking container based on this, irrespective of the change of an emissivity.

A temperature detection device for a heating cooker according to the present invention comprises a heating means for heating a cooking container, an infrared intensity detection means for detecting infrared intensity of infrared rays emitted from the cooking container, and the infrared intensity detection means. Temperature detecting means for detecting the temperature of the cooking container based on the infrared intensity detected at the first characteristic configuration,
The infrared intensity detecting means is
The first wavelength in which the wavelength is different from each other in the wavelength measurement target range, and the change of the infrared intensity emitted from the cooking container with respect to the temperature change is larger in the first wavelength range than in the second wavelength range. Configured to detect infrared intensity in each of the wavelength region and the second wavelength region,
The temperature detecting means is
A reference temperature of the cooking container is obtained based on a ratio between the infrared intensity for the first wavelength range emitted from the cooking container and the infrared intensity for the second wavelength range emitted from the cooking container. Reference temperature calculation processing,
Infrared rays in the first wavelength range with respect to temperature changes in a reference body having a radiation characteristic with a small change in emissivity with respect to a change in wavelength over the entire range or almost the entire range of the wavelength measurement target and a known emissivity. Based on the correlation indicating the change in intensity and the infrared intensity for the first wavelength range emitted from the cooking container, the same infrared intensity as the infrared intensity for the first wavelength range emitted from the cooking container A first temperature calculation process for obtaining the temperature of the reference body corresponding to the intensity as a first temperature;
Based on the correlation indicating the change in the infrared intensity in the second wavelength range with respect to the temperature change in the reference body, and the infrared intensity for the second wavelength range emitted from the cooking container, from the cooking container A second temperature calculation process for obtaining, as a second temperature, the temperature of the reference body corresponding to the same infrared intensity as the infrared intensity of the emitted second wavelength region;
An emissivity estimation process for estimating an emissivity of the cooking container based on the reference temperature, the first temperature, and the second temperature;
The emissivity estimated in the emissivity estimation process, and the infrared intensity for the first wavelength range radiated from the cooking container or the infrared intensity for the second wavelength range radiated from the cooking container The temperature calculation process for obtaining the temperature of the cooking container is executed based on the above.

  As a result of earnest research to obtain a configuration for detecting the temperature of the cooking container regardless of the difference in emissivity of the cooking container, the applicant has found the emissivity from various measured data as described later. It is possible to estimate the emissivity of a cooking container that has not been cooked, and the temperature of the cooking container can be detected from the estimated emissivity and the infrared intensity detected by the infrared intensity detecting means. I found out that

FIGS. 6 to 10 show the results of measurement by the applicant of the correlation between the temperature and the infrared intensity of cooking containers made of various materials.
A line L1 in FIG. 6 shows a correlation indicating a change in infrared intensity in the first wavelength region with respect to a change in temperature for a black body furnace as an example of the reference body, and a line L2 in FIG. The correlation which shows the change of the infrared intensity in the 2nd wavelength range with respect to the change of temperature is shown. FIG. 7 shows the measurement results (indicated by white circles) of the infrared intensity in the first wavelength range when the black paint pan is heated to a plurality of predetermined temperatures (for example, 100 ° C., 200 ° C., 300 ° C.) The measurement results of infrared intensity in two wavelength regions (indicated by black circles in the figure) are shown in association with the correlation of the blackbody furnace. FIG. 8 shows the measurement results of the infrared intensity in the first wavelength region (indicated by white circles in the figure) when the silver paint pan is heated to a plurality of predetermined temperatures (for example, 100 ° C., 200 ° C., 300 ° C.). The result and the measurement result of the infrared intensity in the second wavelength region (indicated by black circles in the figure) are shown in association with the correlation of the black body furnace. Further, FIG. 9 shows the measurement result of infrared intensity in the first wavelength range when the aluminum pan is heated to a predetermined temperature (for example, 100 ° C., 200 ° C., 300 ° C.) and the second result. The measurement result of infrared intensity in the wavelength region (indicated by black circles in the figure) is shown in association with the correlation of the blackbody furnace.

  And based on the correlation shown in the line L1 of FIG. 6 and the infrared intensity for the first wavelength range radiated from the cooking container, the same infrared intensity as the infrared intensity for the first wavelength range radiated from the cooking container The temperature of the reference body corresponding to can be obtained as the first temperature. Further, based on the correlation shown in the line L2 in FIG. 6 and the infrared intensity for the second wavelength range radiated from the cooking container, the same infrared intensity as the infrared intensity for the second wavelength range radiated from the cooking container. The temperature of the reference body corresponding to can be obtained as the second temperature.

  FIG. 10 shows the ratio of the infrared intensity in two different wavelength ranges (first wavelength range and second wavelength range) detected by the infrared intensity detection means and the temperature of the cooking container emitting infrared rays. Correlation is shown. From this figure, it can be seen that the correlation is substantially the same regardless of the difference in the material of the cooking container, in other words, the difference in the emissivity of the cooking container. And, for example, using one of the representative correlations among them, in the two wavelength regions (the first wavelength region and the second wavelength region) in the infrared intensity detection means for the cooking container to be a temperature measurement target The reference temperature of the cooking container to be temperature-measured can be determined from the infrared intensity detected and the infrared intensity ratio and the typical correlation.

  From the measurement results as shown in FIGS. 6 to 10, the applicant uses the reference temperature (T0), the first temperature (T1), and the second temperature (T2) detected as described above. For example, as an example of the relationship, a calculated value [(T1-T2) / T0] obtained by dividing the difference value between the first temperature and the second temperature by the reference temperature is obtained in a state corresponding to various reference temperatures, Results as shown in FIG. 11 were obtained. Then, from the measurement result shown in FIG. 11, the calculated value [(T1-T2) / T0] is different from each other when the material of the cooking container is different, and what is the cooking material as long as the material is the same. Since the temperature is substantially constant, the information on the reference temperature, the first temperature, and the second temperature is preliminarily measured for cooking containers made of various materials to be mounted on the heating cooker. It has been found that it is possible to estimate the emissivity of the placed cooking container.

  Moreover, since the change of the infrared intensity with respect to the temperature change of the cooking container is set so that the first wavelength region is larger than the second wavelength region, the temperature of the cooking container with the ratio of the pair of infrared intensities. The rate of change with respect to the change of is large, and the reference temperature of the cooking container can be obtained with a high error and a small error.

  Therefore, using these measurement results, the temperature detecting means first cooks based on the ratio of the infrared intensity for the first wavelength range and the infrared intensity for the second wavelength range emitted from the cooking container. A reference temperature calculation process for obtaining the reference temperature of the container is executed. Next, radiation from the cooking container based on the correlation indicating the change in infrared intensity in the first wavelength range with respect to the temperature change in the reference body and the infrared intensity for the first wavelength range emitted from the cooking container. First temperature calculation processing for obtaining the temperature of the reference body corresponding to the same infrared intensity as the infrared intensity for the first wavelength range as the first temperature, and the infrared intensity in the second wavelength range with respect to the temperature change in the reference body The correlation corresponding to the infrared intensity corresponding to the second wavelength range radiated from the cooking container, corresponding to the same infrared intensity as the infrared intensity for the second wavelength range radiated from the cooking container A second temperature calculation process for obtaining the temperature of the reference body as the second temperature is executed, and based on the reference temperature, the first temperature, and the second temperature, the cooking container Than it executes the emissivity estimation process for estimating the Iritsu. However, the relationship between the reference temperature, the first temperature, and the second temperature is not limited to the calculated value [(T1-T2) / T0], and various relationships can be set.

  And the temperature detection means is about the emissivity estimated in the emissivity estimation process, the infrared intensity for the first wavelength range radiated from the cooking container, or the second wavelength range radiated from the cooking container. Based on the infrared intensity, a temperature calculation process for determining the temperature of the cooking container is executed. For example, when either the infrared intensity for the first wavelength range or the infrared intensity for the second wavelength range radiated from the cooking container is divided by the emissivity, the reference body has the same temperature as the cooking container at that time. The temperature of the cooking container at that time can be determined from the correlation shown in FIG. 6 and the infrared intensity of the reference body.

  As a result, the emissivity of the cooking container can be estimated based on the detection information of the infrared intensity as described above even if the emissivity of the cooking container to be temperature detected is not known. The temperature of the cooking container can be detected regardless of the difference in emissivity using the emissivity and the infrared intensity measured for the cooking container.

  Therefore, according to the first feature configuration, by estimating the emissivity of the cooking container based on the detection information of the infrared intensity, it becomes possible to detect the temperature of the cooking container regardless of the change in the emissivity. It came to be able to provide the temperature detection apparatus for heating cookers.

  According to a second feature configuration of the present invention, in addition to the first feature configuration, the temperature detecting unit divides a difference value between the first temperature and the second temperature by the reference temperature as the emissivity estimation process. The emissivity of the cooking container is estimated based on the calculated value.

  According to the second characteristic configuration, the temperature detecting means estimates the emissivity of the cooking container based on a calculated value obtained by dividing a difference value between the first temperature and the second temperature by the reference temperature. From the measurement results of the present applicant as shown in FIG. 11, the calculated value becomes different from each other when the material of the cooking container is different, and at any temperature as long as the material is the same cooking container. However, since it is clear that the value is always almost constant, the emissivity of the cooking container can be estimated as an accurate value as much as possible.

  Therefore, according to the second feature configuration, by using the emissivity of the cooking container estimated as an accurate value, the temperature detection device for the cooking device that can accurately detect the temperature of the cooking container. I was able to provide.

  The third characteristic configuration of the present invention is that, in addition to the first characteristic configuration or the second characteristic configuration, the emissivity of the reference body is 0.9 or more.

  According to the third characteristic configuration, since the emissivity of the reference body is 0.9 or more, if the container is made of a material generally used as a cooking container, the emissivity of the cooking container is equal to the emissivity of the reference body. Since the emissivity is the same or smaller than that, there is an advantage that the reliability when obtaining the first temperature and the second temperature is increased. That is, if the emissivity of the reference body is lower than 0.9, depending on the type of the cooking container, the emissivity of the cooking container may be greater than the emissivity of the reference body. There may be both cases where the rate is smaller than the emissivity of the reference body, and there is a possibility that the reliability when obtaining the first temperature and the second temperature may be low, but the emissivity of the reference body If it is 0.9 or more, there will be no such thing and the reliability when calculating | requiring said 1st temperature and said 2nd temperature will become high.

  Therefore, according to the third characteristic configuration, since the reliability when obtaining the first temperature and the second temperature is increased, the reliability in estimating the emissivity of the cooking container is improved, and the cooking container It came to be able to provide the temperature detection apparatus for heating cookers which can detect temperature correctly.

  According to a fourth feature configuration of the present invention, in addition to any one of the first feature configuration to the third feature configuration, the infrared intensity detection means is within a range of 3.1 μm or more and 4.2 μm or less as the first wavelength region. A wavelength range selected from the range of not less than 8.0 μm and not more than 20.0 μm is set as the second wavelength range, and the infrared intensity of each of the plurality of wavelength ranges is detected. It is in the point comprised as follows.

  According to the fourth characteristic configuration, a wavelength range selected from a range of 3.1 μm to 4.2 μm is set as the first wavelength range, and a range of 8.0 μm to 20.0 μm is set as the second wavelength range. A wavelength range selected from the following range is set.

That is, if the cooking container is a heating cooker that is heated by, for example, a flame formed of a burner, when the infrared intensity of infrared rays emitted from the cooking container is detected via the flame by the infrared intensity detection means, the flame CO ₂ and H ₂ O exist in a gas state. And since the actual flame in the stove emits high-intensity infrared rays due to the emission of CO ₂ and H ₂ O, the emission is caused by noise generation in the infrared intensity detection means of infrared rays emitted from the cooking container. Cause. Since CO ₂ and H ₂ O emit infrared rays in the range of 2.4 μm to 3.1 μm and in the range of 4.2 μm to 8.0 μm, the first wavelength as described above By setting the region and the second wavelength region, it is possible to remove the influence of noise associated with the infrared light emission of the flame, thereby making it possible to detect the temperature as accurately as possible.

  Therefore, according to the 4th characteristic structure, even if it is a cooking-by-heating machine provided with a burner as a heating means, it is for cooking-by-heating equipment which can detect temperature as accurately as possible in the state where the influence of the noise accompanying infrared light emission of a flame was reduced The temperature detection device can be provided.

DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment in which a temperature detection device for a heating cooker according to the present invention is applied to a gas stove as a heating cooker will be described based on the drawings.
As shown in FIG. 1, the gas stove can be mounted with a flat top plate 1 having a circular heating opening 1 a and a cooking container N such as a cooking pan such that it is spaced above the opening 1 a. Gotoku 2, a gas combustion burner 30 as a heating means for heating the cooking container N placed on the Gotoku 2, and a combustion control device 3 for controlling the operation of the burner 30 are provided. .

  The burner 30 is a Bunsen combustion type internal flame type burner. The gas nozzle 31 ejects the fuel gas G supplied through the fuel supply passage 5, the fuel gas G is ejected from the gas nozzle 31, and the fuel gas G An annular gas pipe is provided with a mixture tube 32 to which combustion air is supplied by the suction action associated with the jetting of the gas and a plurality of flame ports 33 for jetting the gas mixture to the inner periphery, and the gas mixture is supplied from the mixture tube 32. The burner body 34 is provided, and the burner 30 is provided below the opening 1a.

  In the burner 30, the mixture of the fuel gas G and air supplied from the mixing pipe 32 into the burner body 34 is ejected in a substantially horizontal direction from the flame port 33 toward the center of the burner body 34, and is ejected. The mixture of the fuel gas G and air burns, and a flame F is formed upward through the opening 1a.

  The fuel supply path 5 is provided with a fuel supply intermittent valve 6 for intermittently supplying the fuel gas G to the gas nozzle 31 and a fuel supply amount adjusting valve 7 for adjusting the supply amount of the fuel gas G to the gas nozzle 31. In the lower part of the burner body 34 of the burner 30, there is provided a juice receiving tray 8 for receiving boiled food that has fallen through the opening 1 a.

  Further, the stove has an infrared intensity detection as an infrared intensity detection means that is located below the top plate 1 and is located in the center of the soup pan 8 and detects the intensity of infrared rays emitted from the cooking container N. A temperature detection device is provided that includes a unit 40 and temperature detection means 50 that detects the temperature of the cooking container N based on the intensity of infrared rays detected by the infrared intensity detection unit 40.

  And the said infrared intensity detection part 40 is comprised so that the infrared intensity about each of the several different wavelength range in the infrared rays radiated | emitted from the container N for cooking may be detected, and the said temperature detection means 50 is the infrared intensity detection part 40. The temperature of the cooking container N is detected on the basis of the relationship of the infrared intensity for each of the plurality of wavelength ranges detected in step (1). Further, the infrared intensity detection unit 40 is configured to detect infrared intensity in a wavelength region set in a region outside the wavelength region where the radiation intensity from the flame of the burner 30 is strong in the infrared wavelength range. .

  Next, various measurement data performed by the present applicant using a plurality of types of cooking containers in order to set a plurality of wavelength ranges to be measured by the infrared intensity detection unit 40 will be specifically described. To do. Here, as a plurality of types of cooking containers, a cooking container (hereinafter referred to as a black coating pan) painted black on a metal surface, a cooking container (hereinafter referred to as a silver coating pan) painted silver on a metal surface, and the like. The results of measurement using each of the cooking containers (hereinafter referred to as aluminum pans) using an aluminum plate are shown.

  2 to 4 show the spectrum of infrared radiation intensity when the temperature changes when heated in the range from room temperature (25 ° C) to about 300 ° C for each of the black paint pan, silver paint pan, and aluminum pan. Spectral data is shown. As is clear from these figures, infrared rays are radiated in the wavelength range of 1.5 μm or more and several tens of μm or less in the temperature range of the cooking container during cooking, for example, from room temperature to about 300 ° C. For example, it has sufficient radiation intensity that can be detected by various infrared sensors within a range of 3.5 μm or more and 15 μm or less.

  FIG. 5 shows spectral data of the infrared radiation intensity emitted from the flame formed by the gas combustion type burner 30. As is clear from this figure, out of the infrared wavelength range, In the range of 2.4 μm or more and 3.1 μm or less, and in the range of 4.2 μm or more and 8.0 μm or less, radiation from the flame is strong. Therefore, it is desirable to set the detection target wavelength range in which the infrared intensity is detected by the infrared intensity detector 40 outside the wavelength range where the radiation from such a flame is strong.

  And after considering the radiation area of infrared rays from the cooking container as described above, the influence of flame, etc., even when using a cooking container having a different emissivity, the cooking container with as little error as possible is used. The first wavelength range selected from the range of 3.1 μm to 4.2 μm, and the wavelength range of 8.0 μm to 20. The second wavelength range selected from the range of 0 μm or less is set.

  Specifically, as the wavelength region for infrared detection by the infrared intensity detector 40, the first wavelength region K1 selected within the wavelength region α1 of 3.5 μm or more and 4.0 μm or less, and 8 μm or more and The second wavelength region K2 selected from within the wavelength region α2 of 13 μm or less is set, and the infrared intensity in each of the two wavelength regions K1 and K2 is detected. In addition, as can be seen from FIGS. 2 to 4, the first wavelength range K1 is set to a wavelength range in which the change in infrared intensity with respect to the temperature change of the cooking container is larger than the second wavelength range K2. ing. In other words, in the first wavelength region K1, the resolution for the change in the infrared intensity with respect to the change in temperature is larger than the resolution in the second wavelength region K2. The first wavelength region K1 may use a part of the wavelength region α1 or may use the entire wavelength region α1. Similarly, the second wavelength region K2 may use a part of the wavelength region α2 or may use the entire wavelength region α2.

  FIG. 6 shows a correlation between infrared intensities in the first wavelength range K1 and the second wavelength range K2 when the temperature of the blackbody furnace is changed for a blackbody furnace having an emissivity of about 1.0. Showing the relationship. In the figure, the line L1 indicates the correlation between the temperature of the black body furnace and the infrared intensity for the first wavelength range K1, and the line L2 indicates the correlation between the temperature of the black body furnace and the infrared intensity for the second wavelength range K2. Is shown.

  The blackbody furnace corresponds to a reference body having a radiation characteristic with a small change in emissivity with respect to a change in wavelength over the entire range or almost the entire range of the wavelength measurement target, and the emissivity being known in advance. The emissivity is 0.9 or more. Specifically, the emissivity is approximately 1.0 and has a constant characteristic over the entire range of the wavelength measurement target range.

  FIG. 7 shows the measurement result of the infrared intensity in the first wavelength region K1 detected by the infrared intensity detector 40 when the black paint pan is changed to 100 ° C., 200 ° C., and 300 ° C. (white circles in the figure). And the measurement result of the infrared intensity in the second wavelength region K2 (indicated by black circles in the figure) correspond to the correlation (lines L1, L2) between the temperature of the black body furnace and the infrared intensity as shown in FIG. It is described. Since the emissivity of the black paint pan is substantially constant at about 0.9 regardless of the change in wavelength, the infrared intensity of the black paint pan in either case of the first wavelength range K1 or the second wavelength range K2 is It is a value corresponding to approximately 0.9 times the infrared intensity of the black body furnace at the same temperature as the temperature of the black paint pan at that time.

  Incidentally, the infrared intensity in the first wavelength range K1 is measured not only at 100 ° C., 200 ° C., and 300 ° C. but also at a plurality of other temperatures, so that it can be easily compared with the detected value of the black body furnace. In FIG. 7, only the above three points are represented in a simplified form. Such a simple display form is the same in the case of the following silver paint pots and aluminum pots.

  Further, FIG. 8 shows the infrared intensity in the first wavelength region K1 detected by the infrared intensity detector 40 when the silver paint pan is changed to 100 ° C., 200 ° C., and 300 ° C. (indicated by white circles in the figure). ) And the measurement results of the infrared intensity in the second wavelength region K2 (indicated by black circles in the figure) correspond to the correlation between the temperature of the black body furnace and the infrared intensity (lines L1, L2) as shown in FIG. It is described. Since the emissivity of the silver paint pan is approximately 0.4 regardless of the change in wavelength, the infrared intensity of the silver paint pan is either in the first wavelength range K1 or the second wavelength range K2. It is a value corresponding to approximately 0.4 times the infrared intensity of the black body furnace when the temperature is the same as the temperature of the silver paint pan at that time.

  Further, FIG. 9 shows the measurement result of the infrared intensity in the first wavelength region K1 detected by the infrared intensity detector 40 when the aluminum pan is changed to 100 ° C., 200 ° C., and 300 ° C. (white circles in the figure). And the measurement results of the infrared intensity (indicated by black circles in the figure) in the second wavelength region K2 correspond to the correlation between the temperature of the black body furnace and the infrared intensity (lines L1, L2) as shown in FIG. It has been described. Since the emissivity of the aluminum pan is approximately constant at about 0.3 regardless of the change in wavelength, the infrared intensity of the aluminum pan at that time is the same in either case of the first wavelength range K1 or the second wavelength range K2. It is a value corresponding to approximately 0.3 times the infrared intensity of the black body furnace when the temperature is the same as the temperature of the aluminum pan.

  FIG. 10 shows the ratio of the infrared intensity (A) in the first wavelength region K1 and the infrared intensity (B) in the second wavelength region K2 detected by the infrared intensity detector 40, that is, the object relative to the infrared intensity ratio (B / A). The relationship with the temperature is shown. As can be seen from the description in FIG. 10, in the black paint pan, the silver paint pan, and the aluminum pan, the infrared intensity ratio (B / A) changes depending on the temperature in substantially the same state and has substantially the same characteristics. ing. That is, if the infrared intensity ratio (B / A) is the same, the temperature of the cooking container N with respect to the infrared intensity ratio (B / A) is substantially the same.

  Accordingly, a cooking container to be heated is stored in advance for any one of a plurality of representatives of the correlation between the infrared intensity ratio (B / A) and the temperature of the cooking container N. For N, the ratio of the infrared intensity in the first wavelength range K1 and the infrared intensity in the second wavelength range K2 detected by the infrared intensity detection unit 40, that is, the infrared intensity ratio (B / A), is obtained, and the actually measured infrared intensity ratio The temperature of the cooking container N can be determined as the reference temperature T0 from (B / A) and the correlation stored in advance. Regarding the correlation between the infrared intensity ratio (B / A) and the temperature of the cooking container N, for example, an average value of a plurality of data may be obtained and the average value may be stored.

And this applicant discovered the following things from the measurement result shown in FIGS.
That is, each of the black paint pan, the silver paint pan, and the aluminum pan has the same infrared intensity as that of the first wavelength region K1 emitted from the cooking container at 100 ° C., 200 ° C., and 300 ° C. The corresponding black body furnace temperature (first temperature) T1 is from the black body furnace temperature (second temperature) T2 corresponding to the same infrared intensity as the infrared intensity for the second wavelength region K2 radiated from the cooking container. The temperature becomes too high.

  Using the detected values of the first temperature T1, the second temperature T2, and the reference temperature T0 measured for various cooking containers, the difference value between the first temperature T1 and the second temperature T2 is used as the reference temperature T0. The correlation between the calculated value [(T1-T2) / T0] divided by and the reference temperature T0 was obtained as shown in FIG. In addition, an average value of a plurality of temperatures of the calculated value [(T1-T2) / T0] is obtained, and the correlation between the average value of the calculated values and the emissivity of the cooking container is linear as shown in FIG. Obtained as correlation. From FIG. 11, it can be seen that the calculated value [(T1-T2) / T0] is substantially constant even when the temperature of the cooking container changes, and from FIG. 12, the calculated value [(T1-T2) / T0]. It can be seen that T0] and the emissivity of the cooking container have a predetermined correlation that changes in a substantially linear manner.

  Therefore, such measurement data is measured for various materials and stored in advance, and even when the emissivity of the cooking container N that is a temperature measurement target is not known, the infrared intensity detection unit 40 By measuring the infrared intensity in the first wavelength region K1 and the infrared intensity in the second wavelength region K2, the temperature of the cooking container N can be detected from the measurement result.

Based on the above results, the temperature detecting means 50 is configured as follows.
That is, the temperature detecting means 50 is based on the ratio of the infrared intensity for the first wavelength range K1 emitted from the cooking container N and the infrared intensity for the second wavelength range K2 emitted from the cooking container N. Reference temperature calculation processing for determining the reference temperature of the cooking container N, radiation characteristics having a small change in emissivity with respect to a change in wavelength over the entire range or almost the entire range of the wavelength measurement target, and the emissivity is known in advance. Radiated from the cooking container N based on the correlation indicating the change in the infrared intensity in the first wavelength range K1 with respect to the temperature change in the reference body and the infrared intensity for the first wavelength range K1 emitted from the cooking container N. First temperature calculation processing for obtaining the temperature of the reference body corresponding to the same infrared intensity as the infrared intensity for the first wavelength region K1 as the first temperature T1, The second wavelength emitted from the cooking container N based on the correlation indicating the change in the infrared intensity in the second wavelength range K2 with respect to the conversion and the infrared intensity for the second wavelength range K2 emitted from the cooking container N Based on the second temperature calculation process for obtaining the temperature of the reference body corresponding to the same infrared intensity as the infrared intensity for the region K2 as the second temperature T2, the reference temperature T0, the first temperature T1, and the second temperature T2. Based on the emissivity estimation process for estimating the emissivity of the cooking container N, the emissivity estimated in the emissivity estimation process and the infrared intensity of the second wavelength region K2 radiated from the cooking container N The temperature calculation process for determining the temperature of the cooking container N is then executed.

  As the emissivity estimation process, the temperature detecting unit 50 calculates the difference value between the first temperature T1 and the second temperature T2 by the reference temperature T0 [(T1-T2) / T0]. Based on this, the emissivity of the cooking container N is estimated.

Next, the configuration of the infrared intensity detection unit 40 will be specifically described.
As shown in FIG. 1, the infrared intensity detection unit 40 is disposed in a state of being inserted from below into an opening formed in the central part of the soup pan 8. It is configured to detect the infrared intensity of the infrared rays radiated and introduced from the bottom of the placed cooking container N. As shown in FIG. 1, the infrared intensity detector 40 includes two bandpass filters 41a and 41b having different wavelength ranges of infrared rays to be transmitted, and infrared rays that have passed through the two bandpass filters 41a and 41b. Are provided with two infrared detecting elements 42a and 42b, and two different wavelength ranges in the infrared rays radiated from the cooking container N, that is, the first wavelength range K1 and the second wavelength range. The infrared intensity for each of the wavelength ranges K2 is detected. Incidentally, the band pass filters 41a and 41b are configured to selectively transmit only infrared rays in the corresponding wavelength region. A thermopile or the like can be used as the two infrared detection elements 42a and 42b that detect the infrared intensity in the above wavelength range.

Next, a process for obtaining the temperature of the cooking container N by the temperature detecting means 50 will be specifically described.
The temperature detecting means 50 includes a correlation indicating a change in infrared intensity in the first wavelength region K1 with respect to a change in temperature in a black body furnace as an example of the reference body, and a second wavelength region K2 with respect to a change in temperature in the black body furnace. Correlation indicating a change in infrared intensity (hereinafter also referred to as first storage data) (see lines L1 and L2 in FIG. 6), the infrared intensity ratio (B / A) with respect to the temperature of the cooking container as described above Among the correlations indicating the change of the above, a predetermined representative one (hereinafter also referred to as second storage data) (see FIG. 10), and the above-described measurement of the cooking container made of various materials Correlation (hereinafter also referred to as third storage data) between the average value of the calculated value [(T1-T2) / T0] for various temperatures and the emissivity of the cooking container N (see FIG. 12) S has provided in a state stored in a memory, not previously shown. Incidentally, these characteristics can be stored in various forms, for example, by obtaining an approximate expression for each correlation, or by storing it as map data.

  And the temperature detection means 50 performs the said reference temperature calculation process first, as shown in FIG. 13 (step 1). That is, the ratio between the infrared intensity for the first wavelength range K1 and the infrared intensity for the second wavelength range K2 in the infrared rays radiated from the cooking container N detected by the infrared intensity detection unit 40, that is, the actually measured infrared intensity ratio. The cooking container is obtained from the correlation between the actually measured infrared intensity ratio and the second stored data, that is, the infrared intensity ratio (B / A) stored in advance and the temperature of the cooking container (see FIG. 10). A reference temperature T0 for N is obtained.

  Next, the temperature detection means 50 executes the first temperature calculation process (step 2). That is, in the state where the cooking container N is placed on the virtues 2 and the burner 30 is adjusted to the heated state, the first wavelength region of the infrared rays emitted from the cooking container N by the infrared intensity detection unit 40. The infrared intensity at K1 is measured. And the 1st wavelength range radiated | emitted from the container N for cooking from the measured infrared intensity and the correlation (line L1 of FIG. 6) of the infrared intensity in 1st wavelength range K1 among said 1st memory | storage data. A first temperature T1, which is the temperature of the black body furnace corresponding to the same infrared intensity as that of K1, is calculated.

  Next, the temperature detection means 50 executes the second temperature calculation process (step 3). That is, the infrared intensity in the second wavelength region K2 of the infrared rays radiated from the cooking container N is measured by the infrared intensity detector 40. And the 2nd wavelength range radiated | emitted from the container N for cooking from the measured infrared intensity and the correlation (line L2 of FIG. 6) of the infrared intensity in 2nd wavelength range K2 among said 1st memory | storage data. A second temperature T2, which is the temperature of the black body furnace corresponding to the same infrared intensity as that of K2, is calculated.

  Next, the temperature detecting means 50 executes the emissivity estimation process (step 4). That is, using the calculated values of the reference temperature T0, the first temperature T1, and the second temperature T2, the calculation is performed by dividing the difference value between the first temperature T1 and the second temperature T2 by the reference temperature T0. The value [(T1-T2) / T0] is obtained, and the emissivity of the cooking container is estimated from the calculated value and the correlation (see FIG. 12) in the third storage data.

  Next, the temperature detection means 50 executes the temperature calculation process (step 5). That is, when the infrared intensity for the second wavelength region K2 radiated from the cooking container N is divided by the emissivity estimated in step 4 above, the infrared radiation in the black body furnace at the same temperature as the temperature of the cooking container N at that time The strength can be determined. And the temperature of the black body furnace at that time can be calculated | required from the infrared intensity in the calculated | required black body furnace, and the correlation (line L2) of FIG. is there.

  At this time, the infrared intensity for the second wavelength region K2 radiated from the cooking container N is used when the temperature of the cooking container N is low, as is apparent from FIGS. However, since the infrared ray with a large intensity is radiated and a large output can be obtained by the infrared detection unit 40, the temperature of the current cooking container N can be detected with high accuracy.

  Then, the temperature information obtained by the temperature detection means 50 is output to the combustion control device 3, and the combustion control device 3 uses the fuel supply amount adjustment valve 7 based on the temperature obtained by the temperature detection means 50. By controlling the temperature of the cooking container N within the set range when the cooking container N is heated by the burner 30, and the burner when the temperature of the cooking container N rises above the upper limit temperature. The emergency stop control for stopping the combustion of 30 is performed.

[Another embodiment]
Hereinafter, other embodiments are listed.

(1) In the above-described embodiment, the temperature detection unit performs the cooking as the emissivity estimation process based on a calculated value obtained by dividing a difference value between the first temperature and the second temperature by the reference temperature. In estimating the emissivity of the cooking container, the correlation between the average value of the calculated values [(T1-T2) / T0] and the emissivity of the cooking container shown in FIG. 12 is used. However, instead of such a configuration, for example, the calculation measured at various temperatures for a cooking container made of various materials as shown in FIG. The value [(T1-T2) / T0] may be stored as map data, and the emissivity may be estimated using this map data.

  Further, the emissivity estimation process is not limited to using an operation value obtained by dividing a difference value between the first temperature and the second temperature by the reference temperature, but the first temperature, the second temperature, and As the relationship of the reference temperature, another calculated value that can be expressed in a state corresponding to the emissivity may be used. In short, any value that can estimate the emissivity may be used.

(2) In the above-described embodiment, the temperature detection unit calculates the temperature using the infrared intensity for the second wavelength range radiated from the cooking container as the temperature calculation process. Instead of such a configuration, the temperature may be calculated using the infrared intensity of the first wavelength range radiated from the cooking container.

(3) In the above embodiment, the black body furnace is used on the assumption that the emissivity of the reference body is 0.9 or more. However, the black body furnace is not limited to such a black body furnace and the emissivity is 0.9 or more. An object other than the body furnace may be used, or an object having an emissivity of less than 0.9 may be used.

(4) In the above embodiment, as the wavelength range for infrared detection by the infrared intensity detection means, the first wavelength range selected within the wavelength range of 3.5 μm or more and 4.0 μm or less, and 8 μm or more and The second wavelength region selected from within the wavelength region of 13 μm or less is set, and the infrared intensity of each of these two wavelength regions is detected. However, the present invention is not limited to this configuration. A wavelength range selected from the range of 3.1 μm to 4.2 μm is set, and the second wavelength range is set to a wavelength range selected from the range of 8.0 μm to 20.0 μm. If it is.

(5) In the above embodiment, the stove provided with the internal flame type burner for injecting and burning the air-fuel mixture inward from the annular burner main body as the heating cooker has been shown. A stove provided with a Bunsen combustion type burner to be used may be used.
That is, as shown in FIG. 14, the burner 30 is exposed to the upper side through the opening formed in the top plate 1, and is an external flame type burner provided with a flame port 33 for injecting the air-fuel mixture upward and burning it. In this configuration, the burner body 35 forming the flame opening 33 is provided in a cylindrical shape, and a through hole 36 penetrating in the vertical direction is formed at the center thereof. The infrared intensity through the through hole 36 is detected. The upper end portion of the through hole 36 is covered with an infrared transmissive window portion 37.

(6) In the above embodiment, the infrared intensity detection means includes a plurality of infrared detection elements that individually detect the infrared rays that have passed through the plurality of bandpass filters, and is configured to detect the infrared intensity for each different wavelength range. However, instead of such a configuration, the position is switched so that a plurality of band-pass filters act alternately on one infrared detection element capable of detecting all infrared rays in a plurality of wavelength ranges, It is good also as a structure which detects the infrared rays intensity | strength of a mutually different wavelength range using the detection value of the infrared detection element in each of the switched state.

(7) In the above-described embodiment, the infrared intensity detecting means is exemplified to detect the intensity of infrared incident along the vertical direction located on the lower side of the center portion of the burner. The present invention is not limited to this, and it is possible to detect the intensity of infrared rays incident in the oblique direction by shifting the position in the horizontal direction from the center of the burner.

(8) In the above embodiment, a gas combustion type burner is used as the heating means. However, the heating means is not limited to the burner, for example, a halogen lamp is used, and an electric resistance wire is incorporated. You may comprise by an electric heating part, such as what uses a sheathed heater, or the thing using the magnetic field generation coil which performs electromagnetic induction heating (usually called "IH").

Schematic configuration diagram of the cooking device The figure which shows the spectrum data of the radiation intensity radiated | emitted from the container for cooking The figure which shows the spectrum data of the radiation intensity radiated | emitted from the container for cooking The figure which shows the spectrum data of the radiation intensity radiated | emitted from the container for cooking A diagram showing the spectral data of the radiation intensity emitted from the flame Diagram showing correlation between temperature of blackbody furnace and infrared intensity Diagram showing correlation between temperature of blackbody furnace and infrared intensity and measured infrared intensity Diagram showing correlation between temperature of blackbody furnace and infrared intensity and measured infrared intensity Diagram showing correlation between temperature of blackbody furnace and infrared intensity and measured infrared intensity The figure which shows the relationship between the temperature of the container for cooking, and infrared rays intensity ratio The figure which shows the relationship between the temperature of a container for cooking, and a calculated value Diagram showing the relationship between computed value and emissivity Control flow chart of temperature detection means The schematic block diagram of the heating cooker of another embodiment

Explanation of symbols

30 Heating means 40 Infrared intensity detecting means 50 Temperature detecting means K1 First wavelength range K2 Second wavelength range T0 Reference temperature T1 First temperature T2 Second temperature

Claims (4)

A heating means for heating the cooking container, an infrared intensity detection means for detecting the infrared intensity of the infrared rays emitted from the cooking container, and the cooking based on the infrared intensity detected by the infrared intensity detection means A temperature detection device for a cooking device comprising a temperature detection means for detecting the temperature of the container for use,
The infrared intensity detecting means is
The first wavelength in which the wavelength is different from each other in the wavelength measurement target range, and the change of the infrared intensity emitted from the cooking container with respect to the temperature change is larger in the first wavelength range than in the second wavelength range. Configured to detect infrared intensity in each of the wavelength region and the second wavelength region,
The temperature detecting means is
A reference temperature of the cooking container is obtained based on a ratio between the infrared intensity for the first wavelength range emitted from the cooking container and the infrared intensity for the second wavelength range emitted from the cooking container. Reference temperature calculation processing,
Infrared rays in the first wavelength range with respect to temperature changes in a reference body having a radiation characteristic with a small change in emissivity with respect to a change in wavelength over the entire range or almost the entire range of the wavelength measurement target and a known emissivity. Based on the correlation indicating the change in intensity and the infrared intensity for the first wavelength range emitted from the cooking container, the same infrared intensity as the infrared intensity for the first wavelength range emitted from the cooking container A first temperature calculation process for obtaining the temperature of the reference body corresponding to the intensity as a first temperature;
Based on the correlation indicating the change in the infrared intensity in the second wavelength range with respect to the temperature change in the reference body, and the infrared intensity for the second wavelength range emitted from the cooking container, from the cooking container A second temperature calculation process for obtaining, as a second temperature, the temperature of the reference body corresponding to the same infrared intensity as the infrared intensity of the emitted second wavelength region;
An emissivity estimation process for estimating an emissivity of the cooking container based on the reference temperature, the first temperature, and the second temperature;
The emissivity estimated in the emissivity estimation process, and the infrared intensity for the first wavelength range radiated from the cooking container or the infrared intensity for the second wavelength range radiated from the cooking container A temperature detection device for a cooking device configured to execute a temperature calculation process for obtaining the temperature of the cooking container based on the above. The temperature detection means, as the emissivity estimation process,
The cooking according to claim 1, wherein the emissivity of the cooking container is estimated based on a calculated value obtained by dividing a difference value between the first temperature and the second temperature by the reference temperature. Temperature detector for dexterity.   The temperature detection device for a heating cooker according to claim 1 or 2, wherein the emissivity of the reference body is 0.9 or more. The infrared intensity detecting means is
The wavelength range selected from the range of 3.1 μm to 4.2 μm is set as the first wavelength range, and the second wavelength range is selected from the range of 8.0 μm to 20.0 μm. The temperature detection device for a heating cooker according to any one of claims 1 to 3, wherein a wavelength range is set and the infrared intensity of each of the plurality of wavelength ranges is detected.

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