JP2004139821A - Temperature detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect the temperature of a non-heating object by using a plurality of temperature sensors, in a temperature detection device of a heating appliance for cooking. <P>SOLUTION: The plurality of temperature sensors 4 are used for providing information for determining detection of a warpage level and displacement of the heating object 1 by a control part 6, the control part 6 is used for changing a heating control algorithm based on the determination, and thereby the temperature of the non-heating object 1 is controlled. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device for detecting the temperature of a non-heated object in a cooking appliance such as an electromagnetic cooker.
[0002]
[Prior art]
In the related art, a temperature is detected by a thermistor via a top plate under a non-heated object, and heating is controlled based on the detected temperature of the thermistor. In addition, it is known that a plurality of temperature sensors are provided (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-A-5-290967
[Problems to be solved by the invention]
In the above conventional techniques, since the temperature of the non-heated object is measured through a top plate made of glass or the like, it is difficult to accurately measure the temperature of the non-heated object, and the measured temperature and the actual temperature are not measured. The temperature error of the non-heated material was large. In addition, since the time lag until the detected temperature rises is larger than the temperature rise of the non-heated object, the followability is not good. Therefore, it is difficult to detect the temperature of the non-heated object, and accurate temperature control cannot be performed.
[0005]
[Means for Solving the Problems]
The present invention solves this conventional problem, and uses a plurality of temperature sensors, the control unit detects the temperature measured by the temperature sensor whose temperature rises quickly and employs the measured temperature as a control input value, so that non-heating is accurately performed. This makes it possible to measure the temperature of an object.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
The invention according to claim 1 is the cooking heater having a plurality of temperature sensors, a control unit that inputs the detection values of the plurality of temperature sensors, calculates and outputs a heating state, and a heating unit. The unit calculates the highest temperature among the temperatures detected by the plurality of temperature sensors, and adopts the highest temperature as a control input value to determine the heating state. By employing the detected temperature of the temperature sensor whose temperature has risen quickly, it is possible to minimize the error between the temperature of the non-heated object and the detected temperature of the temperature sensor.
[0007]
The invention according to claim 2 is characterized in that at least one of the plurality of temperature sensors is arranged near the center where an unheated object such as a pan is placed, so that the unheated object is placed at the center. It can be used as a criterion for determining whether or not the bottom surface of the non-heated object is warped.
[0008]
According to the third aspect of the present invention, the control unit calculates a difference between a temperature sensor disposed near the center where an unheated object such as a pan is placed and another temperature sensor, and the difference is calculated from a reference value. Is larger, it is determined that the bottom surface of the non-heated object is warped, and by changing the heating control method, it is possible to determine whether the bottom surface of the non-heated object is warped. It becomes.
[0009]
According to a fourth aspect of the present invention, the control unit calculates a difference between the temperature detected by the temperature sensor disposed in the vicinity of the center where the non-heated object such as a pan is placed, and another temperature sensor. Since the control unit determines the degree of warpage of the bottom surface of the object and changes the heating control method, it is possible to determine the degree of warpage of the bottom surface of the non-heated object.
[0010]
According to a fifth aspect of the present invention, when the difference between the maximum temperature and the measured temperatures of the other temperature sensors among the detected temperatures of the plurality of temperature sensors is equal to or more than a reference value, a non-heated object is provided above the temperature sensor. The temperature detector is characterized by detecting that there is no non-heated object and detecting that the non-heated object is small or not placed at the center. It is possible to have a function of detecting that the user is being alerted and calling the user's attention.
[0011]
【Example】
Next, embodiments of the present invention will be described with reference to the drawings.
[0012]
(Example 1)
In FIG. 1, a non-heated object 1 is a cooking utensil such as a pot or a frying pan. Foods and the like are put into the non-heated object 1 and are heated directly or indirectly from the cooking heater 2 to heat the foods and the like in the non-heated object 1. The material of the non-heated object 1 may be a metal-based material or a ceramic such as a clay pot.
[0013]
The cooking heating appliance 2 includes a top plate 3, a temperature sensor 4, a heating unit 5, and the like. The cooking heater 2 directly or indirectly heats the non-heated object 1 placed on the top plate 3, measures the temperature of the non-heated object 1 from the temperature detected by the temperature sensor 4, and controls heating. By doing so, foods and the like in the non-heated object 1 are heated. The heating method of the cooking heater 2 may be a method in which a gas or the like is burned and the heat is indirectly received and heated by the non-heated object 1, or the heating unit 5 is heated by a heating coil. In addition, an induction heating method in which the non-heated object 1 is directly heated by a high-frequency magnetic field generated by flowing a high-frequency current through the heating unit 5 may be used. The top plate 3 is made of glass or the like, and does not necessarily have to be flat, and may have holes.
[0014]
The temperature sensor 4 measures the temperature of the non-heated object 1. The mounting position of the temperature sensor 4 may be on the upper surface or the lower surface of the top plate. The temperature sensor 4 may be a contact type such as a couple wire or a thermistor, or a non-contact type such as an infrared ray.
[0015]
The heating unit 5 is for heating the non-heated object 1, and may be a burner that generates heat from the heating unit 5 itself, or the heating unit 5 itself does not generate heat. It may be a kind of induction heating type heating coil existing for heating the heating object 1.
[0016]
In FIG. 2, the control unit 6 controls the heating unit 5 with the temperature detected by the temperature sensor 4 as an input to perform temperature control. Conventionally, in the cooking heating appliance 2 having such a configuration, only one temperature sensor 4a is disposed at a position that is the center of the heating unit 5. In this case, when the bottom surface of the non-heated object 1 is warped, heat is not easily transmitted to the top plate 3, and as a result, the temperature detected by the temperature sensor 4 is detected to be lower than the temperature of the non-heated object 1. there were. Further, there is no guarantee that the non-heated object 1 is placed at the center of the heating unit 5, and when the non-heated object 1 is placed off the center of the heating unit 5, a further error occurs.
[0017]
Further, the top plate 3 is made of glass or the like, and is largely influenced by the thermal characteristics of the top plate 3, and a time lag occurs between the rise in the temperature of the non-heated object 1 and the rise in the temperature detected by the temperature sensor 4. This is because there is a danger of ignition of oil when there is no heating in the non-heated material 1 or when there is only a small amount of oil in the non-heated material 1. It will not happen. Therefore, it is necessary to design in consideration of safety. However, since the heating power has to be reduced more than necessary, it has caused a decrease in performance.
[0018]
However, in the present invention, the non-heated object 1 is configured to take advantage of the characteristic that the temperature above the heating section 5 is the highest. That is, by providing a plurality of temperature sensors 4 which were conventionally only at the center of the heating unit 5, the temperature of a portion above the heating unit 5 is measured. Since this portion is a portion having the highest temperature, it is determined that the temperature is dangerous if the temperature exceeds a predetermined value, and the heating can be stopped to maintain safety. Further, since this is a portion where the temperature of the non-heated object 1 is easily transmitted to the top plate 3 as compared with the conventional central portion, the response is faster than that of the conventional temperature sensor 4a located at the center of the heating portion 5. In addition, the time lag between the rise in the temperature of the non-heated object 1 and the rise in the temperature detected by the temperature sensor 4 can be reduced.
[0019]
Conversely, it is possible to determine the degree of warpage of the non-heated object 1 using the point at which the temperature detected by the temperature sensor 4 disposed at the center is lower than the temperatures detected by the other temperature sensors 4. FIG. 3 is a flowchart of the warp pot determination.
[0020]
In FIG. 3, in step 1, first, a plurality of temperature sensors 4 detect temperatures. This step 1 is executed by the number of the temperature sensors 4. Step 2 is a step of detecting the highest temperature among the plurality of detected temperatures detected in step 1. In step 3, the center temperature is subtracted from the maximum temperature, and the value is set as X. In step 4, X calculated in step 3 is compared with a predetermined warp pot determination coefficient Y determined from a difference between the maximum temperature and the center temperature when the pot is not a warp pot, and X is smaller than Y. In this case, it is determined that the non-heated object 1 has no warpage. In step 5, since X is larger than Y in step 4, it is a warp pot and its level is determined. In step 5, the warp pot determination coefficients A and X, which are larger than the warp pot determination coefficient Y, are compared. When X is smaller than A, the warp level of the non-heated product 1 is set to A. By repeating this step 5 as needed, the warpage level of the non-heated object 1 can be determined more finely.
[0021]
When the cooking heater 2 is of the induction heating type, whether or not the bottom surface of the non-heated object 1 is warped is an important factor, and the heating control algorithm can be changed depending on the warpage level.
[0022]
Further, when the difference between the maximum temperature and the plurality of temperature sensors is a detected temperature equal to or greater than a predetermined value, it can be determined that there is no non-heated object 1 on the temperature sensor 4. It is also possible to detect a deviation from the center and the like, and these are also important elements of the heating control. By detecting these, advanced heating control becomes possible.
[0023]
Further, all or a part of the control function in the embodiment of the present invention is realized by a program, and the procedure is as shown in the flowchart shown in FIG. At this time, the heating control is performed by the control unit 6 of FIG. The above program can be easily realized using a DSP or a general-purpose computer as well as a microcomputer. Also, by recording the program on a recording medium or distributing the program using a communication line, the program can be easily distributed and installed.
[0024]
【The invention's effect】
As described above, according to the present invention, a safer and more sophisticated temperature control can be performed by adopting, as a control input value, the highest detected temperature having a fast response speed by a plurality of temperature sensors. . In addition, by judging the level of warpage or deviation of the bottom surface of the non-heated object, the user can be alerted or applied to temperature control, which brings benefits to the user of the heating appliance for cooking. .
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a cooking heating appliance according to an embodiment of the present invention. FIG. 2 is a control block diagram of the cooking heating appliance. FIG.
DESCRIPTION OF SYMBOLS 1 Non-heating thing 2 Cooking heating appliance 3 Top plate 4 Temperature sensor 5 Heating part 6 Control part

Claims (5)

A plurality of temperature sensors, a control unit that inputs a detection value of the plurality of temperature sensors, calculates a heating state and outputs a control signal, and a cooking heating appliance having a heating unit, wherein the control unit includes a plurality of heating units. A temperature detecting device for a cooking utensil for determining a heating state by employing a maximum temperature among control temperatures detected by a temperature sensor. The temperature detection device according to claim 1, wherein at least one of the plurality of temperature sensors is disposed near a center where an unheated object such as a pan is placed. The difference between the detected temperature of the temperature sensor disposed near the center where the unheated object such as a pan is placed and the temperature detected by the other temperature sensor is calculated by the control unit, and when the difference is larger than a reference value, the temperature of the unheated object is calculated. The temperature detecting device according to claim 1, wherein it is determined that the bottom surface is warped, and the heating control method is changed. The control unit calculates the difference between the temperature of the temperature sensor disposed near the center where the unheated object such as a pan is placed and the temperature detected by the other temperature sensors, and the control unit calculates the degree of warpage of the bottom surface of the unheated object based on the difference. The temperature detection device according to any one of claims 1 to 3, wherein the determination is made and the heating control method is changed. If the difference between the maximum temperature and the measured temperatures of the other temperature sensors among the detected temperatures of the plurality of temperature sensors is equal to or greater than the reference value, it is determined that there is no non-heated object above the temperature sensor, and the non-heated object is determined. The temperature detection device according to any one of claims 1 to 4, wherein the temperature detection device detects that the temperature detection device is small or not located at the center.

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