JP2003161445A - Heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect a temperature and reduce restriction on a placing method and the size of food. <P>SOLUTION: This heating cooker has a noncontact temperature detector 6 for detecting a temperature of a straight line or curved-shaped continuous area of a surface of the food 2 and a food placing tray 3 in a heating chamber 1 from the outside of the heating chamber 1 via an opening window 5 arranged in a wall surface of the heating chamber 1, a food temperature calculating means 8 for calculating a food temperature from the temperature distribution of the continuous area detected by this noncontact temperature detector 6, and a heating control means 9 for controlling a heater 4 according to the calculated food temperature. A temperature detecting scan of the noncontact temperature detector 6 is intermittently performed, and an intermittent period is automatically changed according to a temperature rising speed of the food. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooker having a structure for detecting the surface temperature of food in a non-contact manner.

[0002]

2. Description of the Related Art Heretofore, various cooking appliances of this type have been proposed, in which an infrared sensor is used to detect the surface temperature of food to control heating.

[0003] One of them relates to the point detection of the surface temperature of the food, basically, the surface temperature of one point of the food is detected by using an infrared ray sensor of one element, and the detected temperature is used as the temperature of the food. Is to be represented as. In the case of a microwave oven equipped with a turntable, food moves as the turntable rotates.
It is possible to detect the temperature on a concentric circle with respect to the rotation axis of the turntable (for example, refer to Patent Document 1).

Another conventional technique is to detect the heating state of the food surface in more detail by measuring the surface temperature of the food product two-dimensionally. As a two-dimensional detection method, a method in which a plurality of infrared sensors are arranged in a matrix to detect a thermal image of food has been proposed. In the case where there is a turntable such as a microwave oven, the turning radius of the turntable is proposed. , Or arrange multiple infrared sensors in an array to view the diameter, or
It has been proposed to perform a two-dimensional temperature measurement on the turntable while the turntable makes one revolution by reciprocally moving a temperature detection spot by an infrared sensor of the element on the radius of gyration or diameter (for example, Patent Document 1). Two
reference).

[0005]

[Patent Document 1] Japanese Patent Application Laid-Open No. 1-147224

[Patent Document 2] Japanese Unexamined Patent Publication No. 5-322179

[0006]

However, the above conventional structure has the following problems. First, Patent Document 1
The prior art shown in (1) basically obtains only the temperature information of one point on the surface of the food, and is therefore effective only when the temperature of the entire food is uniform. There is no guarantee that the detected temperature is representative of the temperature of the entire food in a cooking device with uneven heating such as a microwave oven. Further, there are restrictions on the place and size of the food with respect to the position and size of the temperature detection spot of the infrared sensor, and the usability is not good.

Next, in the conventional technique disclosed in Patent Document 2,
The two-dimensional temperature detection method using the matrix or array infrared sensor becomes very expensive.
The products that can be adopted are limited. Further, the method of achieving the function by utilizing the rotating operation of the turntable has a problem that it cannot be adopted in the heating cooker without the turntable.

The present invention solves the above-mentioned problems and provides a heating cooker capable of accurately detecting temperature even in a cooking cooker without a turntable at a low cost, since there are few restrictions on the place and size of food. The purpose is to do.

[0009]

In order to achieve the above object, the present invention provides a heater for heating food in a heating chamber and a food and food placing table inside the heating chamber from outside the heating chamber through an opening window provided on a wall surface of the heating chamber. A non-contact temperature detector that detects the temperature of a linear or curved continuous area on the surface, and a food temperature calculation means that calculates the food temperature from the temperature distribution of the linear or curved continuous area detected by this non-contact temperature detector And a heating control means for controlling the heater according to the calculated food temperature, wherein the non-contact temperature detector reciprocally rotates an infrared sensor around one rotation axis at a predetermined angle. The surface of the mounting table is linearly or curvedly scanned to detect the temperature, and the temperature detection scanning of the non-contact temperature detector is performed intermittently. Intermittent period of, and automatically changing cooking appliance according to the temperature rise rate of the food.

[0010]

The object of the present invention can be achieved by the constitutions described in each claim, and therefore the constitutions described in each claim and the effects thereof will be described in detail below.

According to a first aspect of the present invention, there is provided a heater for heating food in the heating chamber, and a straight line or a curve on the surface of the food and food placing table in the heating chamber from outside the heating chamber through an opening window provided on the wall of the heating chamber. Non-contact temperature detector to detect the temperature of the continuous region of the shape, food temperature calculating means to calculate the food temperature from the temperature distribution of the linear or curved continuous region detected by this non-contact temperature detector, the calculated food Heating control means for controlling the heater according to the temperature, and the non-contact temperature detector linearly moves the infrared sensor about one rotation axis at a predetermined angle to reciprocally rotate the food and the food placing table surface. Alternatively, the temperature detection scanning of the non-contact temperature detector is performed intermittently in a curved line, and the temperature detection scanning of the non-contact temperature detector is performed intermittently. A cooking appliance which automatically varied according to the temperature rise rate of the goods.

According to the second aspect of the present invention, the non-contact temperature detector is swung to the left and right, and one round trip of the swing motion is taken as a unit, and the temperature data detected at that time and on the way back are used to measure the temperature at that time. The cooking device according to claim 1, which calculates a food temperature.

The structure of the invention according to claim 3 is
The intermittent cycle of the temperature detection scanning of the non-contact temperature detector is configured to automatically change according to the speed while measuring the temperature rise value of the food, and in the case of heating a large food for a long time, the scanning is performed. The heating cooker according to claim 1 or 2, wherein the intermittent cycle is lengthened.

As described above, the non-contact temperature detector having the structure of the present invention scans the food and food table surface by reciprocally rotating the infrared sensor about one rotation axis at a predetermined angle, and The temperature is detected in a linear or curved continuous region formed by the above.

The temperature detection scan of this non-contact temperature detector is
The configuration is performed intermittently.

The intermittent cycle of the temperature detection scan of the non-contact temperature detector is automatically changed according to the temperature rising speed of the food.

The food temperature calculating means using this scanning contact temperature detector calculates the food temperature at that time from the temperature data detected during one round trip of the temperature detection scan by the non-contact temperature detector. It is configured to do.

The plurality of non-contact temperature detectors detect the temperature of the food and the food placing table surface in different linear or curved regions in the heating chamber, and the food temperature calculating means includes the non-contact temperature detectors. The food temperature is calculated from a plurality of temperature distribution data output from the.

As a non-contact temperature detector for obtaining a linear or curved temperature detection area, the cost can be reduced by swinging one infrared sensor to the left and right and scanning the food and food placing table. it can. Such an infrared sensor swing operation is intermittently performed at a required cycle. The life of the swing mechanism can be extended by changing the intermittent cycle according to the temperature rising rate of the food. In addition, a highly accurate measurement value can be obtained by calculating the food temperature at that time from the temperature data detected on the way and the way back in one reciprocating swing motion.

[0020]

EXAMPLES Examples of the present invention will be described below. The present invention is to obtain the temperature distribution of the food or the surface of the food placing table by a non-contact temperature detector that detects the temperature of a continuous region formed in a straight line or a curved line on the food placing table in the heating chamber. The food portion and the other portion are discriminated from the temperature distribution data, the temperature of the food is calculated from the temperature data of the food portion, and the heater is controlled based on the food temperature.

A specific embodiment of the present invention applied to a microwave oven will be described below with reference to FIGS. FIG. 1 is a block diagram of a cooking device according to an embodiment of the present invention. In FIG. 1, 1 is a heating chamber, 2 is food, 3 is a food placing table, and 4 is a heater such as a magnetron. 6 is a non-contact temperature detector, which is an opening window 5 provided above the heating chamber 1.
The temperature of the food 2 in the heating chamber 1 is detected via. The non-contact temperature detector 6 uses an infrared sensor such as a pyroelectric infrared sensor or a thermopile infrared sensor, and is configured to move one infrared sensor or to configure a plurality of infrared sensors in an array. By
The temperature distribution of a continuous region formed in a straight line or a curved line on the food 2 or the food placing table 3 is detected. 7
Is a food area discriminating means, which is a non-contact temperature detector 6 shown in FIG.
Of the temperature detection spots S1, S2, ... Sn are used to determine the temperature data of the food portion and other portions, and the temperature rise value is different between the food 2 and the other portions. I'm taking advantage of that. Reference numeral 8 denotes a food temperature calculation means, which calculates the temperature of the food 2 based on the temperature data output from the non-contact temperature detector 6 or the food area determination means 7. 9 is a heating control means,
The heater 4 is controlled based on the food temperature calculated by the food temperature calculating means 8.

In the above configuration, the non-contact temperature detector 6 has a function of detecting the temperature of a continuous region by the temperature detection spot array composed of S1, S2, ... Sn as shown in FIG. The temperature distribution of can be detected. FIG. 3 shows the temperature distribution curve 10 in the heating chamber 1 in FIG. 2, where the horizontal axis represents the position of the temperature detection spot, that is, the detection point, and the vertical axis represents the detected temperature. In this embodiment, there are 17 temperature detection points P1 to P17. When the temperature data D1 to D17 at each point are input from the non-contact temperature detector 6 to the food region discriminating means 7, the magnitude relation with the predetermined temperature discriminating value 11 is compared. In this case, the points larger than the temperature determination value 11 are 7 points of P6 to P12, and it can be determined that this area corresponds to the food 2. The temperature judgment value 11 may be a fixed value that has been obtained in advance by experiments or the like, or the temperature data D1 to D17 of the detection points P1 to P17.
It may be a value associated with an average value of 17. The surface temperature of the food 2 is calculated based on the average value 12 of the temperature data D6 to D12 at the detection points P6 to P12.

The control of the heater 4 by the heating control means 9 is
It can be performed based on the average value obtained in the above D6 to D12. That is, when the average value reaches a predetermined value, heating control is performed such as stopping the heater 4 or reducing the power to maintain the temperature. As another method, the average value and the maximum value of the temperature data D11 (M
A method of controlling the heating sequence while monitoring AX) may be used. In this case, it is possible to perform control such that power is turned off when the maximum value exceeds a predetermined value, and heating is terminated when the average value reaches a certain temperature.

FIG. 4 illustrates another embodiment of the food region discriminating means 7 of the present invention, and shows a distribution curve 13 of the temperature rise rate in the heating chamber 1 in FIG. The horizontal axis represents the temperature detection points, and the vertical axis represents the temperature rise rate. Temperature data D1 (t) to D corresponding to temperature detection points P1 to P17
When 17 (t) is input from the non-contact temperature detector 6 to the food region discriminating means 7, the temperature data D1 (t
−τ) to D17 (t−τ) and the temperature data D input this time
From 1 (t) to D17 (t), temperature rise rate E at each point
1 to E17 are calculated, and the magnitude relationship with the predetermined temperature rise rate determination value 14 is compared. In this case, the temperature rise rate judgment value 1
Points greater than 4 are P6 to P12, and it can be determined that this area corresponds to the food 2. The temperature rise rate determination value 14 may be a fixed value that has been obtained in advance by experiments or the like, or may be a value associated with the average value of the temperature rise rates E1 to E17 at the detection points P1 to P17.

5 (a) and 5 (b) show two arrangements of the temperature detection spots. Assuming that the temperature detection spot diameter is A, the temperature detection spot interval L1 in FIG. 5A is L1 = A / 2, and the temperature detection spot interval L2 in FIG. 5B is L2 = A. That is, as is clear from the figure, A / 2 to A is effective for the spot interval L for detecting the temperature distribution in the linear or curved continuous region.

Next, in the configuration of the present invention, placing the food 2 in a linear or curved continuous temperature detection region in a wide range as much as possible is a point that enables more accurate temperature measurement. Therefore, as shown in FIG. 6, the point can be realized by a simple configuration in which the marking 15 indicating the temperature detection area is displayed on the food placing table 3. As another method, as shown in FIG. 7, the position of the linear or curved temperature detection spot row is changed from S1 to Sn to S.
The same effect can be obtained by adopting a configuration in which 1a to Sna can be freely changed. Further, as shown in FIG. 8, the range of the temperature detection spot row is set to the maximum X (S1 to Sn).
The same effect can be obtained by adopting a structure that can be freely changed. For example, Y (Si to Si + j) in the figure
It is also possible to use it to limit the places where you want to detect temperature.

As a means for obtaining the linear or curved continuous temperature detection region of the present invention, as described above, one infrared sensor is moved or a plurality of infrared sensors are arranged in an array. is there. In FIG. 9, one infrared sensor 6a is reciprocally rotated around one rotary shaft 16 at a predetermined angle θ to scan the temperature detection spot of the infrared sensor 6a on the food placing table 3 in the heating chamber 1. , A linear continuous temperature detection region is formed. That is, when the infrared sensor 6a has an angle of 61, temperature detection spots S1 and 6i form Si, and when 6n, Sn forms.

In such a structure, the scanning timing of the infrared sensor 6a is shown in FIGS.
It shows in (b). For simplicity, n = 8 is set. FIG. 10A is an explanatory diagram showing the first scanning timing of the infrared sensor. In the figure, T1 is the scanning time interval between the temperature detection points, and in the case of the pyroelectric sensor, T1 is T11 and T.
The temperature of the temperature detection spot S1 is detected at T11, and the temperature of the chopper is detected at T12. T2 is the time required for one forward scan on one side, and approximately T2 = T1 × 8.
Is. T3 is the waiting time until one scan on one side of the return, T4
Is the time required for one return one-side scan, and usually T2 = T4. In addition, T2 and T4 detect the temperature from P1 to P8.
It is necessary that the temperature rise due to heating performed during the heating is short enough not to cause a problem. T5 is the next one
This is the waiting time until scanning. The above T3 and T5 are automatically changed according to the speed of the food 2 while measuring the temperature rise value of the food 2, so that T3 and T5 are lengthened when the food 2 is heated for a long time. Thus, the intermittent period of scanning can be lengthened and the life of the scanning mechanism can be extended.

FIG. 10B is an explanatory view of the second scanning timing when the scanning of the infrared sensor 6a is reciprocated as one set. That is, the temperature detection at each of the temperature detection points P1 to P8 is performed twice during a short time in which the scan makes one reciprocation, and the average value of the detected temperature at each detection point is used as the measurement value at that point to stabilize the measurement value. Can be obtained. T1 is a scanning time interval between each temperature detection point, T2a is a time required for reciprocal scanning, and T3 is a waiting time until the next scanning, which are as described in FIG. 10A.

Next, a method for measuring the temperature of food using two non-contact temperature detectors will be described. FIG. 11 shows a configuration in which two non-contact temperature detectors are provided, and linear continuous temperature detection regions formed by them are arranged orthogonal to each other, and each temperature detection spot row has S1 to Sn and V1 to V1.
It is Vm. FIGS. 12A and 12B show the temperature distribution of each of these temperature detection spot arrays. As described above, the food portion is discriminated from the temperature distribution curves 17 and 19 based on the magnitude relation with the predetermined temperature determination values 18 and 20, and the temperature of the food 2 is calculated from the temperature data of the portion. By using the orthogonal temperature detection regions, a wide range of temperature information of the food 2 can be obtained, and the temperature detection accuracy can be improved. The temperature determination values 18 and 20 may be the same value.

FIG. 13 shows a configuration in which the linear continuous temperature detection regions by the two non-contact temperature detectors 6 are arranged in parallel with each other, and the respective temperature detection spots are S1 to S1.
Sn and W1 to Wn. FIG. 14A and FIG. 1 show the temperature distributions of these temperature detection spots.
4 (b). For each of the temperature distribution curves 21 and 23, the food portion is discriminated from the magnitude relation with the predetermined temperature determination values 22 and 24 as described above, and the temperature of the food 2 is calculated from the temperature data of the portion. By using the parallel temperature detection regions, a wide range of temperature information about the elongated food 2 can be obtained, and the temperature detection accuracy can be improved. The temperature determination values 22 and 24 may be the same value.

Although the case where there are two non-contact temperature detectors 6 has been described, the present invention is not limited to two.

Further, in the case where each non-contact temperature detector 6 uses a scanning type continuous region temperature detector as described with reference to FIG. 9, each temperature detection scan should be carried out one by one. Thus, the processing speeds of the food region discriminating means 7 and the food temperature calculating means 8 do not have to be so high, and such an apparatus can be realized at low cost.

According to the configuration of this embodiment, the food 2 or the food placing table 3 is constructed by moving one infrared sensor 6a or by arranging a plurality of infrared sensors 6a in an array. Since it is possible to detect the temperature distribution in a continuous area that is formed in a straight line or a curved line on the top, it is possible to detect the surface temperature of food even with a cookware without a turntable, and to control the heating temperature with high accuracy. Can be realized.

[0035]

As described above, in the heating cooker of the present invention, the temperature of the food and the food or food placing table surface in a linear or curved continuous region is detected by the non-contact temperature detector, and the food temperature is determined from the temperature distribution. The following effects can be obtained by calculating (1) Compared to a simple structure in which the temperature of one point on the food surface is fixedly measured, extremely high-precision temperature measurement is possible, so heating unevenness especially in microwave ovens is possible. It is effective in some cookware. (2) Compared with an expensive structure in which the temperature distribution on the entire food surface is measured by using a matrix-shaped sensor, it is very inexpensive and most suitable for a cooking device without a turntable. (3) Especially, it automatically distinguishes between food and other places,
Since the food temperature is calculated from the temperature data at the food portion, accurate temperature measurement can be performed even if the food storage location or size is slightly different. (4) Since the temperature detection area can be changed to some extent by the user, the way the food is placed can be adjusted to be more effective by temperature detection. (5) By providing a plurality of linear or curved temperature detection areas, a wider range of temperature information of food can be obtained, and accurate temperature measurement can be performed even in a heating cooker without a turntable.

[Brief description of drawings]

FIG. 1 is a block diagram of a cooking device according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a temperature detection spot of the non-contact temperature detector.

FIG. 3 is an explanatory diagram showing a temperature distribution in a temperature detection spot.

FIG. 4 is an explanatory diagram showing a temperature rise rate at a temperature detection spot.

FIG. 5A is an explanatory diagram showing a first arrangement of temperature detection spots, and FIG. 5B is an explanatory diagram showing a second arrangement of temperature detection spots.

FIG. 6 is an explanatory view showing a temperature detection area of the food placing table.

FIG. 7 is an explanatory diagram showing changes in the location of the temperature detection spot row.

FIG. 8 is an explanatory diagram showing changes in the range of temperature detection spot rows.

FIG. 9 is a side view showing a rotating state of one infrared sensor of the same.

FIG. 10A is an explanatory diagram showing a first scanning timing of the infrared sensor, and FIG. 10B is an explanatory diagram showing a second scanning timing of the infrared sensor in the same.

FIG. 11 is an explanatory diagram showing an orthogonal arrangement of temperature detection spot rows of the two non-contact temperature detectors.

12 (a) is an explanatory diagram showing a temperature distribution in a temperature detection spot row of the first non-contact temperature detector shown in FIG. 11, and FIG. 12 (b) is the same second second non-contact temperature detection shown in FIG. Diagram showing the temperature distribution in the temperature detection spot array

FIG. 13 is an explanatory diagram showing a parallel arrangement of temperature detection spot rows of two non-contact temperature detectors.

14A is an explanatory diagram showing a temperature distribution in a temperature detection spot row of the first non-contact temperature detector shown in FIG. 13, and FIG. 14B is a second non-contact temperature detection shown in FIG. Diagram showing the temperature distribution in the temperature detection spot array

[Explanation of symbols]

1 heating chamber 2 food 3 food placing table 4 heater 5 open windows 6 Non-contact temperature detector 6a infrared sensor 7 Food area discrimination means 8 Food temperature calculation means 9 Heating control means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05B 6/68 320 H05B 6/68 320Q (72) Inventor Teruhiko Tomohiro 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Sangyo Co., Ltd. F-term (reference) 2G066 AC05 AC16 BA08 BA26 BA60 CA01 CA08 3K086 AA07 BA08 CA04 CB04 CB05 CB06 CC02 CC20 DA02 3L086 AA01 CB05 CB10 CB16 DA20

Claims (3)

[Claims] 1. A heater for heating food in a heating chamber and a temperature of a linear or curved continuous region on the surface of the food and the food placing table in the heating chamber is detected from the outside of the heating chamber through an opening window provided on the wall surface of the heating chamber. A non-contact temperature detector, a food temperature calculating means for calculating a food temperature from a temperature distribution in a linear or curved continuous region detected by the non-contact temperature detector, and a heater is controlled according to the calculated food temperature. And a heating control means, wherein the non-contact temperature detector includes an infrared sensor.
By rotating back and forth around one rotation axis at a predetermined angle, the food and food placing table surface are scanned linearly or curvedly to detect the temperature, and the temperature detection scanning of the non-contact temperature detector is performed intermittently. A heating and cooking device configured such that the intermittent cycle of the temperature detection scan of the non-contact temperature detector is automatically changed according to the temperature rising speed of the food. 2. The non-contact temperature detector is swung to the left and right, and the food temperature at that time is calculated from the temperature data detected in the going and returning in units of one reciprocating swing motion. Cookware. 3. The intermittent cycle of the temperature detection scan of the non-contact temperature detector is automatically changed according to the speed of the temperature rise of the food while measuring the temperature rise value of the food, so that a large food is heated for a long time. The cooking device according to claim 1 or 2, wherein the intermittent period of scanning is lengthened in some cases.