JPH10267285A - Heating cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit correct temperature detection by discriminating noise and a sensor signal. SOLUTION: The temperature a food is detected (S301), and when the detected temperature reaches a finishing temperature, the heating is finished (S302). When the detected temperature has not reached the finishing temperature, the step S303 and following steps are repeated until the detected temperature reaches the finishing temperature. A difference ΔK between the previous detected temperature and the detected temperature of this time is compared with a predetermined value ΔKo (about 2 deg.C) and when ΔK>ΔKo (304), or ΔK>ΔKo is achieved in a past predetermined period of time To (the time of one turn of a turn table) (S306), a detected temperature in the step S303 is decided whether the same has arrived at the finishing temperature or not (305). When ΔK>ΔKo has not been achieved, or the detected temperature in the step S305 has not reached the finishing temperature, the control of above- mentioned steps S303-S306 are repeated until the detecting temperature reaches the finishing temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cooking device,
In particular, the present invention relates to a heating cooker that performs heating while detecting the temperature of food in a cavity (heating chamber) with an infrared sensor.

[0002]

2. Description of the Related Art Some conventional microwave ovens are provided with an infrared sensor. During cooking, the infrared sensor detects infrared radiation emitted from the food placed on the turntable in the cavity (heating chamber), and the control unit detects the temperature of the food based on the detected infrared radiation. Have been. Then, it is monitored whether or not the food has reached a target finishing temperature. The sensor signal indicating the detection result of the infrared ray from the food is usually represented by voltage data, and one half wave is formed for each detection.

[0003] In conventional temperature detection in a microwave oven,
The control unit has sampled the value (or peak value) in a half cycle of the half-wave, and has detected the temperature of the food based on the sampled voltage data. And
During temperature detection, noise and the like may be added to the sensor signal due to the influence of an external power supply or other devices.However, if a conventional microwave oven detects a very large temperature difference during temperature detection, the value is ignored. Or just accept it.

[0004]

However, when a temperature change of a predetermined value or more is detected during temperature detection, if the sensor signal is set to be ignored, the sensor signal indicates the true temperature of the food. If detected, the data is discarded. Also, if the setting is made to accept the data as it is, if the sensor signal is actually noise, incorrect data will be accepted. Therefore, when there is a possibility of being affected by noise, there is a problem that the temperature of the food cannot always be accurately detected from the sensor signal.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a heating cooker capable of distinguishing noise from an original sensor signal and realizing a good finish of food. The purpose is to provide.

[0006]

According to a first aspect of the present invention, there is provided a heating cooker comprising: a heating chamber for storing food; heating means for heating the food in the heating chamber; and a heater for placing the food in the heating chamber. A turntable, a turntable motor that drives the turntable, and an infrared detector that detects infrared light,
A control unit for detecting the temperature of the food based on the infrared rays emitted from the food detected by the infrared detector, wherein the control unit performs the first data at the first timing during the temperature detection. Is detected, and when the second data having a temperature difference greater than or equal to a predetermined value with respect to the first data is detected at a second timing within a predetermined time from the first timing, the detected second data is ignored. The third data is detected at a third timing within a predetermined time from the second timing, and the second data is detected.
When the fourth data having a temperature difference greater than or equal to a predetermined value with respect to the third data is detected at a fourth timing that is later than the third timing within a predetermined time from the timing described above, the fourth data is validated.

According to a second aspect of the present invention, in the heating cooker according to the first aspect, the predetermined time is a time required for one turn of the turntable.

According to a third aspect of the present invention, there is provided a heating cooker for storing food, a heating means for heating the food in the heating chamber, an infrared detector for detecting infrared rays, and an infrared detector. And a control unit for detecting the temperature of the food based on the infrared rays radiated from the food. In the control unit, one temperature detection result of the food is represented by half-wave voltage data, and the control is performed. The means is a predetermined 3
After sampling the data at the point and starting the temperature detection,
In the first sampling, the second largest data among the data at the predetermined three points is valid, and in the second and subsequent samplings, the difference between the maximum value and the minimum value of the data at the predetermined three points is a predetermined value. Is within the range, any one of the data is valid, and if the difference between the maximum value and the minimum value of the data at the three points is outside the predetermined range,
The data with the value closest to the data that was made valid in the previous sampling in that time is made valid.

According to a fourth aspect of the present invention, in the heating cooker according to the third aspect, the predetermined three points are a half of a half wave.
Period and several milliseconds to several tens of milliseconds before a half period and 1 /
This is several milliseconds to several tens of milliseconds after two cycles.

According to a fifth aspect of the present invention, in the cooking device of the third aspect, the predetermined three points include a half-wave peak value, several millimeters to several tens of milliseconds before the peak value, and the peak value. A few milliseconds to several tens of milliseconds later.

According to a sixth aspect of the present invention, in the cooking device of any one of the third to fifth aspects, the predetermined range has a temperature difference of about 2 ° C.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

(1) First Embodiment FIG. 1 shows a microwave oven 100 according to a first embodiment of the present invention.
It is a perspective view of. FIG. 2 shows the microwave oven 10 shown in FIG.
FIG. 2 is a simplified cross-sectional view showing an internal structure of a No. 0. Referring to FIGS. 1 and 2, microwave oven 100 includes infrared sensor 1 on the side of cavity (heating chamber) 17, that is,
It is arranged so as to catch infrared rays 25 emitted from the food 31 from obliquely above. The magnetron 22 supplies a microwave into the cavity 17. Below the magnetron 22, a high-voltage transformer 33 is arranged. The heater 80 used for heating the oven has a cavity 17.
(Cavity 1)
7 The heater below the bottom is not shown). By a key input on the operation panel 34, a cooking heating course is set.
The cooling fan 35 includes the magnetron 22 and the cavity 1.
The peripheral devices (including the infrared sensor 1) whose temperature has been increased by the heat of 7 are cooled. A door 15 is attached to the front of the cavity 17. Further, a control unit (microcomputer) 90 for controlling these devices comprehensively is also provided on the back surface of the operation panel 34. At the bottom of the cavity 17, a turntable 18 for placing food is rotatably provided. A turntable motor 505 for rotating the turntable 18 is disposed below the bottom surface of the cavity 17.

FIG. 3 is a block diagram showing a main electrical configuration of microwave oven 100 shown in FIGS.
Referring to FIG. 3, microwave oven 100 includes infrared sensor 1
, Magnetron 22, operation panel 34, heater 8
0, a control unit (microcomputer) 90, and a turntable motor 505.

FIG. 4 shows the microwave oven 10 shown in FIGS.
9 is a flowchart for explaining the operation of the “0”. FIG.
4, heating is started by the magnetron 22 or the heater 80, and the temperature is detected while the turntable 18 is rotating. This temperature detection is performed a plurality of times within the same rotation.

Step (hereinafter abbreviated as step) S30
In 1, the first temperature detection is performed by the control unit 90 based on the sensor signal of the infrared ray 25 radiated from the food 31 detected by the infrared sensor 1. In S302, S30
The control unit 90 determines whether or not the detected temperature obtained in Step 1 has reached a target finish temperature.

In S302, when it is determined that the detected temperature obtained in S301 has reached the target finish temperature, the control unit 90 ends the heating. If it is determined in S302 that the detected temperature obtained in S301 has not reached the target finish temperature, the control unit 90 performs the second temperature detection in the same rotation after the temperature detection in S301 in S303. Is performed. Then, in S304, a temperature difference ΔK between the first detection temperature obtained in S301 and the second detection temperature obtained in S303 is obtained, and the temperature difference ΔK is calculated as the temperature difference Δ
The controller 90 determines whether or not it is larger than K ₀ .

[0018] S304 in ΔK> ΔK ₀ if not, S3
At 05, the control unit 90 determines whether or not the detected temperature obtained at S303 has reached the target finishing temperature. If ΔK> ΔK ₀ in S304, in S306,
The controller 90 determines whether or not a temperature change ΔK of ΔK> ΔK ₀ has been detected within the past predetermined period T ₀ . The past predetermined period T ₀ is, for example, a time required for the turntable 18 to make one rotation.

[0019] S306 in ΔK in the past within a predetermined period of time T _0>
If it is determined that ΔK ₀ has been reached, in S308, S303
Is valid. And S305
Then, the control unit 90 determines whether or not the detected temperature validated in S308 has reached the finished temperature.

At S306, ΔK> Δ within the past predetermined period T ₀ .
If it is determined that it is not K ₀ , in S307, S303
The temperature detected at is invalidated. Then, returning to S303, the next temperature detection is performed from the temperature detection in the previous S303 until the turntable 18 makes one rotation,
Up to S305 or S307, the same control as described above is performed.

Here, the first S3 after the heating is started.
In the temperature detection at 01, since the previous temperature detection has not been performed, the determination of ΔK> ΔK ₀ performed at S304 is not performed. After the second temperature detection in S303, the steps following the temperature detection in S303 and the determination in S304 are repeated during heating, and the heating is terminated when the detected temperatures in S305 and S303 reach the finishing temperature. In the determination at S304, the difference ΔK between the detected temperature at a certain timing t and the detected temperature at the previous time (one time before S303) is ΔK>
When it is ΔK ₀ , ΔK> in S304 within the past predetermined period T ₀ (within the period when the past turntable 18 makes one rotation)>
If ΔK ₀ , the detected temperature at timing t is valid, and otherwise, it is invalid.

Therefore, even if erroneous data whose temperature suddenly changes due to noise during temperature detection becomes a candidate for sampling data, the erroneous data is not detected continuously, so that erroneous data is not detected. , And is not sampled.

As described above, according to the microwave oven 100 of the first embodiment of the present invention, it is possible to prevent the data with noise from being sampled, and to achieve a good finish of the food.

(2) Second Embodiment A microwave oven according to a second embodiment of the present invention performs sampling of infrared data detected by an infrared sensor by a method different from a conventional microwave oven when performing temperature detection. It is.

The microwave oven according to the second embodiment of the present invention has the same configuration as the microwave oven 100 according to the first embodiment shown in FIGS. Therefore, illustration is omitted.

FIG. 5 is a diagram for explaining an example of a method of sampling an infrared sensor signal used in the microwave oven 100 shown in FIGS.
FIG. 4D is a diagram illustrating an example of a half-wave of a sensor signal when noise is present and sampling thereof. Fig. 5 (1)-
Referring to (4), data of three points a, b, and c are sampled in one sensor signal (that is, one half-wave voltage data). Where b is 半 of a half wave
At the timing of the cycle, data is actually extracted in a conventional microwave oven. a is a point several milliseconds to several tens of milliseconds before b, and c is a point several milliseconds to several tens of milliseconds after b. The half-wave of this infrared sensor signal is represented by voltage data as described above, and a temperature difference of 1 ° C. is represented by a voltage difference of about 20 mV.

Here, even if the sensor signal has noise,
For example, if the voltage error is within 40 mV, it does not significantly affect the finish of cooking, so an error within 40 mV is not regarded as noise. FIGS. 5A to 5D show some examples in which the voltage data is reduced due to the influence of noise. However, the voltage data may be increased in some cases.

In view of the above, in the first half-wave temperature detection, the data of the second largest value among the temperatures detected at the three points a, b, and c on the half-wave is extracted as the detected temperature. You.

In the temperature detection in the second and subsequent half-waves,
When the voltage difference between the maximum value and the minimum value of the three points a, b, and c on the half wave is, for example, within 40 mV (about 2 ° C.), the data at b is unconditionally extracted as the detected temperature. .
When the voltage difference between the maximum value and the minimum value of the three points a, b, and c on the half wave is 40 mV (about 2 ° C.) or more, the value closest to the previous detected temperature is extracted. For example, in the case of (1), the voltage difference between the maximum value and the minimum value of the three points a, b, and c is 4
0 mV (about 2 ° C.) or more, a or c (a = c
) Is extracted, and in the case of (2),
The voltage difference between the maximum value and the minimum value of the three points a, b, and c is 40 m
V (about 2 ° C.) or more, data at b closest to the previous detected temperature is extracted. In the case of (3), a,
The voltage difference between the maximum and minimum values of the three points b and c is 40 mV
(Approximately 2 ° C.) or more, the data at c closest to the previous detected temperature is extracted.
The voltage difference between the maximum and minimum values of the three points b and c is 40 mV
(Approximately 2 ° C.) or more, data at c closest to the previous detected temperature is extracted. However, (1)-
In each previous temperature detection of (4), it is assumed that normal voltage data free from noise is obtained.

FIG. 6 is a flowchart showing the sampling method described with reference to FIG. With reference to FIG.
At 1, the temperature is detected in the first half-wave. S
At 502, the second largest value among the three points a, b, and c is made valid. In S503, it is determined whether the value validated in S502 has reached the finishing temperature. S
If it is determined in 503 that the finishing temperature has been reached,
The oscillation of the magnetron 22 is stopped, and the heating is terminated.
If it is determined in S503 that the finished temperature has not been reached, in S504, temperature detection in the next half-wave is performed. In S505, it is determined whether or not the voltage difference between the maximum value and the minimum value among the three points a, b, and c is less than a predetermined voltage difference ΔV ₀ . In the description of FIG. 5, ΔV ₀ = 40 mV
And said an example.

If it is determined in step S505 that the voltage difference between the maximum value and the minimum value of the three points a, b, and c is equal to or greater than the predetermined voltage difference ΔV ₀ , the process proceeds to step S506, where the previous detection is performed. The data closest to the applied voltage data is regarded as valid. Then, returning to S503, it is determined based on the data made valid in S506 whether or not the finishing temperature has been reached. If the finishing temperature has been reached, the heating is terminated. If the finish temperature has not been reached, the temperature is detected in the next half wave in S504. Hereinafter, the same operation as described above is performed until the food reaches the finished temperature.

If it is determined in step S505 that the voltage difference between the maximum value and the minimum value of the three points a, b, and c is within the predetermined voltage difference ΔV ₀ , one of the three is determined in step S507. (For example, voltage data at b) is made valid. Then, returning to S503, it is determined whether or not the food has reached the finished temperature based on the data in b made valid in S507. If the finishing temperature has been reached, the heating is terminated. If the finishing temperature has not been reached, the next temperature detection is performed in S504. Hereinafter, the same operation as described above is performed until the food 31 reaches the target finishing temperature.

Therefore, voltage data is extracted at a timing of a half cycle of a half-wave and a timing of several milliseconds to several tens of milliseconds, and a voltage difference between the maximum value and the minimum value of the voltage data is about 40 mV. If this is the case, the value closest to the previously detected temperature is extracted as the detected temperature. If the voltage difference between the maximum value and the minimum value of the voltage data is less than 40 mV, the second largest value is the detected temperature. Therefore, it is possible to avoid that data affected by noise is extracted as the detected temperature.

As described above, according to the microwave oven 100 according to the second embodiment of the present invention, it is possible to determine the noise from the original sensor signal and realize a good finish of the food.

The temperature (infrared ray) detection is performed not at the timing of a half cycle of the half wave but at the peak value of the half wave and several millimeters thereof.
The voltage data may be extracted at a timing of about several tens of milliseconds. If the voltage difference between the maximum value and the minimum value of the voltage data at those timings is about 40 mV or more, the value closest to the previously detected temperature is extracted as the detected temperature, and the maximum value and the minimum value of the voltage data are extracted. If the voltage difference from the value is less than 40 mV, the second largest value is extracted as the detected temperature. Thereby, it is possible to avoid that the data affected by the noise is extracted as the detected temperature.

As described above, according to the microwave oven 100 according to the second embodiment of the present invention, it is possible to discriminate noise from the original sensor signal and realize a good finish of food.

[0037]

According to the cooking device of the first aspect, the control unit detects the first data at the first timing during the temperature detection, and the second data within a predetermined time from the first timing. When the second data having a temperature difference greater than or equal to the predetermined value with respect to the first data is detected at the timing, the detected second data is ignored, and the third data within a predetermined time from the second timing is ignored. The third data is detected at the timing, and the fourth data having a temperature difference greater than or equal to the predetermined value with respect to the third data at a fourth timing later than the third timing within a predetermined time from the second timing. Is detected,
Since the fourth data is valid, it can be determined that the fourth data is not erroneous data caused by noise. Therefore, the detected fourth data is effectively used, and a good finish of the food is obtained. Can be realized.

According to the heating cooker of the second aspect, in addition to the effect of the first aspect, if the second data is not data including an error caused by noise, at least after the turntable makes one rotation. , Are again detected as the fourth data.

According to the third aspect of the present invention, the control means samples the data at the predetermined three points on the half-wave. Among the data, the second largest data is valid, and in the second and subsequent samplings, if the difference between the maximum value and the minimum value of the data at predetermined three points is within a predetermined range, any one of the data is determined. If the data is valid and the difference between the maximum value and the minimum value of the data at the three points is out of the predetermined range, the data of the value closest to the data valid in the previous sampling of that time is valid. The data with the noise becomes invalid,
The noise and the original sensor signal are discriminated, and it is possible to realize a good finish of the food.

According to the heating cooker according to the fourth aspect, in addition to the effect of the third aspect, the predetermined three points are set at a half of a half wave.
Period and several milliseconds to several tens of milliseconds before a half period and
Since it is several milliseconds to several tens of milliseconds after two periods, it is generally possible to sample the peak of the half wave and the data before and after the peak.

According to a fifth aspect of the present invention, in addition to the effect of the third aspect, in addition to the effect of the third aspect, the predetermined three points include the peak value of the half-wave, several millimeters to several tens of milliseconds before the peak value, and the peak value. A few millimeters
Since it is several tens of milliseconds later, even if noise is included in the peak value, it is possible to detect the noise based on data at two points before and after the noise.

According to the heating cooker according to the sixth aspect, in addition to the effect of any one of the third to fifth aspects, even if an error occurs in data due to the influence of noise, it is approximately 2 ° C. in terms of temperature. If the error is within the range, it does not significantly affect the finish of the cooking, so if the data has a temperature difference of 2 ° C or more,
It can be determined that there is a possibility of being affected by noise.

[Brief description of the drawings]

FIG. 1 is a perspective view of a microwave oven according to Embodiments 1 and 2 of the present invention.

FIG. 2 is a cross-sectional view showing a simplified internal structure of the microwave oven shown in FIG.

FIG. 3 is a block diagram showing a main electric configuration of the microwave oven shown in FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the microwave oven shown in FIGS.

FIG. 5 is a diagram for explaining an example of a sampling method of an infrared sensor signal used in the microwave oven shown in FIGS. 1 to 3; (1) to (4) show sensor signals when noise is present; FIG. 3 is a diagram showing an example of a half-wave and sampling thereof.

FIG. 6 is a flowchart showing the sampling method described in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared sensor 17 Cavity 18 Turntable 22 Magnetron 34 Operation panel 80 Heater 90 Control part (microcomputer) 100 Microwave oven 505 Turntable motor

Claims (6)

[Claims] 1. A heating chamber for storing food, heating means for heating the food in the heating chamber, a turntable for placing the food in the heating chamber, and driving the turntable A turntable motor, an infrared detector for detecting infrared light, and a control unit for detecting a temperature of the food based on infrared radiation emitted from the food detected by the infrared detector, wherein the control unit includes: Detecting first data at a first timing during the temperature detection, and having a temperature difference greater than or equal to a predetermined value with respect to the first data at a second timing within a predetermined time from the first timing When detecting the second data,
The detected second data is ignored, the third data is detected at a third timing within a predetermined time from the second timing, and the third data is detected at the third time within the predetermined time from the second timing. A heating cooker that validates the fourth data when detecting fourth data having a temperature difference greater than or equal to the predetermined value with respect to the third data at a fourth timing later than the timing. 2. The cooking device according to claim 1, wherein the predetermined time is a time required for the turntable to make one rotation. 3. A heating chamber for storing food, heating means for heating the food in the heating chamber, an infrared detector for detecting infrared rays, and a radiation emitted from the food detected by the infrared detector. A control unit for detecting the temperature of the food based on infrared rays. In the control unit, a result of one temperature detection of the food is represented by half-wave voltage data, and the control unit includes: Data is sampled at predetermined three points on the wave, and after the start of temperature detection, in the first sampling, the second largest data among the data at the predetermined three points is valid, and in the second and subsequent samplings, If the difference between the maximum value and the minimum value of the data at the predetermined three points is within a predetermined range, any one of the data is valid, and the maximum value of the data at the three points is If outside the range difference of the predetermined small value, for that time, and enable the data value closest to enable the data in the previous sampling, the heating cooker. 4. The three predetermined points are a half cycle of the half wave, several milliseconds to several tens of milliseconds before the half cycle, and several milliseconds to several tens of milliseconds of the half cycle. Claim 3. Later
A heating cooker according to claim 1. 5. The predetermined three points are a peak value of the half-wave, several millimeters to several tens of milliseconds before the peak value, and several millimeters to several tens of milliseconds after the peak value. 4. The heating cooker according to 3. 6. The predetermined range has a temperature difference of about 2 ° C.
The heating cooker according to any one of claims 3 to 5, wherein