JP2004028552A - Heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a turntable-less type heating cooker detecting weight of food placed on a table fixed inside a heating room. <P>SOLUTION: This heating cooker having a fixed food placing bed 3 comprises a weight detecting means 15 for detecting weight information of food 4 below approximately the center of the fixed food placing bed 3 and outside of a wave guide 6. On the basis of such information, automatic setting of heating time is performed on the food 4. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heating cooker provided with a fixed food placing table for placing a food to be heated in a heating chamber, for example, a microwave oven or an electronic microwave oven.
[0002]
[Prior art]
In consideration of securing the effective cooking space in the heating room and the cleanability, a method of fixing the table as the food table (turntable-less type or fixed food table type as opposed to the conventional rotating turntable type) There is a heating cooker.
[0003]
In such a conventional heating cooker, as disclosed in Patent Literature 1, an infrared sensor installed at an upper portion of a heating chamber scans a food mounting table during heating of a food and a temperature output of the sensor is maximized. In some cases, a heating antenna is rotated to a position where the object can be heated most efficiently at the position where the object to be heated is mounted, and then stopped at that position to perform heating control.
[0004]
Further, as disclosed in Patent Literature 2, a cooking device (for example, the entire microwave oven) is installed on a weight detection unit that is a separate device, and the total weight of the cooking device before and after feeding food is detected. The relative value (difference) is detected as food weight. In some cases, heating is controlled by automatically setting the heating time based on the detected food weight information.
[0005]
[Patent Document 1]
JP 2001-250672 A [Patent Document 2]
JP-A-8-75172.
[0006]
[Problems to be solved by the invention]
In Patent Document 1 of the related art, in order to detect a local high-temperature portion of an object to be heated as a position of food, erroneous recognition due to unevenness in temperature or uneven heating of a large-volume food or a plurality of foods. There are concerns that cause. In addition, the temperature information from the infrared sensor is information on the surface temperature of the object to be heated.For example, in the case of cooking with low fluidity such as curry and stew, the inside is cooled relative to the surface temperature or covered with wrap. For foods and the like, it is difficult to detect temperature information with high accuracy. It is difficult to optimally cook food by using only the temperature information obtained by the infrared sensor.
[0007]
Further, in Patent Document 2 of the prior art, although the weight of the food is known, the weight of the food to be cooked (the weight of a light weight such as bread, etc.) with respect to the weight of the heating cooker body (the weight of a general household microwave oven is about 20 kg). The weight of food is about 50 g), which makes it difficult to accurately detect the weight of food. Further, when detecting the weight, neither the heating cooker nor the weight detection device can be touched, nor can anything other than food be placed on the heating cooker, and it must be kept in a completely non-contact state.
[0008]
The present invention has been made to solve at least one of the above problems.
[0009]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a heating chamber for storing food, a magnetron for heating the food, a waveguide for guiding an electromagnetic wave generated from the magnetron to the heating chamber, a rotating antenna for stirring the electromagnetic wave, and the rotating antenna. In a heating cooker provided with a heating means configured with a rotary driving means for driving the food and a fixed food mounting table for mounting the food, the weight detection means for detecting the weight information of the food is a fixed food mounting table. It is provided almost outside the waveguide at the lower center so that the weight information of the food can be detected.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
One embodiment of the present invention using a heating cooker will be described taking a turntableless microwave oven or an electronic microwave oven as an example, but the present invention can be applied to other heating cookers.
[0011]
FIG. 1 shows a temperature detecting means 10 and a weight detecting means 15 for detecting information on food 4 in a heating chamber 2 according to an embodiment of the present invention, and a control means 16 for issuing an appropriate heating / cooking command based on the detected information. 1 shows a heating cooker 1 provided with a rotation driving means 9 and a temperature detection driving means 11 for performing a heating cooking operation according to the instruction.
[0012]
The internal structure of the heating cooker 1 shown in the embodiment of the present invention is divided into a heating chamber 2 for storing food 4 to be cooked, and a machine chamber 14 provided on a side surface (right side in the drawing) of the heating chamber 2. .
[0013]
The heating chamber 2 has a heating chamber housing 12 in which left and right side surfaces, a back surface and a ceiling surface, and a bottom surface are integrally formed of a thin plate-like steel material. And a door (not shown) for taking in and out the food 4 made of glass and a thin steel plate provided with a large number of small holes in a punching shape so as not to transmit electromagnetic waves to the outside.
[0014]
Further, a square plate-shaped food placing table 3 (hereinafter, referred to as a table) on which the food 4 is placed is provided below the heating chamber 2 and separates the heating chamber 2 from a gap 2a surrounded by a heating chamber housing 12. The table 3 is elastically supported by a heating chamber housing 12 and a seal member 13.
[0015]
The machine room 14 is located on the side surface of the heating room 2, and the inside thereof is separated by a thin steel plate of the heating room housing 12 so as to block thermal or electromagnetic waves. Inside the machine room 14, a magnetron 5 for generating electromagnetic waves necessary for heating the food 4, control means 16 for controlling the electromagnetic waves from the magnetron 5, and an air-cooling fan (for cooling each electronic component and circuit component) (Not shown) etc. are stored.
[0016]
The electromagnetic wave generated from the magnetron 5 provided in the machine room 14 propagates through the air gap 2 a and the table 3 into the heating chamber 2 via the cylindrical waveguide 6 made of a thin steel plate. A rotary antenna 7 for stirring electromagnetic waves from the waveguide 6 and irradiating the food 4 with the electromagnetic waves from the waveguide 6 is provided in the space 2 a below the table 3. The rotating antenna 7 is driven via a rotating shaft 8 by a rotating driving means 9 provided on the lower side outside the waveguide 6.
[0017]
In this embodiment, the weight detecting means 15 detects the weight information of the food 4 as the first detecting means for detecting the information of the food 4, for example, a capacitance type sensor, a strain type sensor, a pressure sensor or an optical type. The weight detecting means 15 is provided outside the waveguide 6 below the table 3 using a sensor or the like. Between the table 3 and the weight detecting means 15, there is provided a food weight supporting member 17 which is a transmitting member for transmitting the weight information of the food 4 to the weight detecting means 15.
[0018]
Further, as the second detecting means, for example, a temperature detecting means 10 for detecting temperature information of the food 4 (or detecting position information of the food 4 in addition to the temperature information, which will be described in detail later), is used. The temperature detecting means 10 is provided above the heating chamber 2 so as to have a structure capable of detecting almost the entire surface of the table 3 of the heating chamber 2 from above the heating chamber 2. The temperature detection driving means 11 can change the temperature detection direction of the temperature detection means 10.
[0019]
In the present embodiment, the temperature detecting means 10 is rotated by the temperature detecting driving means 11 to scan the table 3. The temperature detection drive means 11 may be a rotary drive or a linear drive system, and may be not only a single-degree-of-freedom system but also a two-degree-of-freedom system or a three-degree-of-freedom system using a plurality of driving mechanisms.
[0020]
The information of the food 4 from the weight detecting means 15 which is the first food information detecting means and the temperature detecting means 10 which is the second food information detecting means is sent to the control means 16 and the processing such as calculation is performed internally. The weight information, the position information, and the temperature information of the food 4 are calculated, and an optimal heating / cooking command is sent to the control drive system based on the information.
[0021]
Here, the control drive system is a magnetron 5 that generates an electromagnetic wave, a rotation drive unit 9, and a temperature detection drive unit 11 for the temperature detection unit 10. A specific control drive system will be described later.
[0022]
The operation of the magnetron 5 is controlled by the control means 16 based on the weight information of the food 4 from the weight detection means 15 as the first detection means, and the irradiation time and output of the electromagnetic wave to the food 4 are controlled.
[0023]
The position information of the food 4 is calculated from the temperature information of the food 4 from the temperature detecting means 10 as the second detection means, and the rotation of the rotation driving means 9 for driving the rotary antenna 7 is controlled by the control means 16 to thereby control the magnetron 5. The food 4 is irradiated with the electromagnetic wave from the food 4 most efficiently.
[0024]
At the same time, the temperature of the food 4 is aimed at, for example, by directing the detection direction of the temperature measuring means 10 directly to the food 4 based on the position information of the food 4, and the optimum finishing temperature of the food 4 is also monitored accurately.
[0025]
According to the present embodiment, the optimal finishing temperature can be obtained by controlling the irradiation time and output of the electromagnetic wave based on the weight of the food 4, and the position of the food 4 can be recognized and the efficient electromagnetic wave irradiation can be performed. The heating time of the food 4 can be shortened, and energy saving can be achieved.
[0026]
Further, since the temperature of the food 4 in the heating and cooking process can be accurately detected in real time by the target temperature measurement of the food 4, problems such as insufficient heating and overheating can be solved. That is, in the present invention, in the turntableless microwave oven, the weight information, the position information, and the temperature information of the food 4 can be obtained, and the food 4 can be heated more efficiently than before based on the information. .
[0027]
Hereinafter, a method for detecting information of food 4 in heating cooker 1 of the present invention and its embodied structure will be described with reference to FIG.
[0028]
FIG. 2 is a cross-sectional view showing the structure of the weight detecting means 15 of the food 4 of the heating cooker 1 shown in FIG. 1, which is an embodiment of the present invention, and its peripheral structure. The side surface of the table 3 on which the food 4 is placed is elastically supported by the heating chamber housing 12 by a sealing member 13 such as silicone rubber or fluorine rubber. Thereby, the table 3 can be freely moved within the elastic deformation by the seal member 13, and the heating chamber 2 above the table 3 on which the food 4 is placed by the table 3 and the seal member 13 and the gap 2 a below the liquid form the liquid. The flow is completely sealed.
[0029]
This is to prevent the food 4 placed on the table 3 of the heating chamber 2, for example, milk, from leaking into the waveguide 6 through the gap 2 a when spilled.
[0030]
Further, a bar-shaped food weight supporting member 17 is attached to the lower center of the table 3, and the weight of the table 3 and the food 4 placed on the table 3 is sent to the weight detecting means 15 by the food weight supporting member 17. It has a structure to transmit directly. In the present embodiment, the weight detecting means 15 for detecting the weight is constituted by one.
[0031]
Since the food weight supporting member 17 is located in the gap 2a and the waveguide 6, the food weight supporting member 17 is made of a non-metallic material so as not to affect the distribution of the electromagnetic wave, and it is better to use a ceramic material or the like which has excellent heat resistance and strength. .
[0032]
The weight detecting means 15 is provided substantially below the center of the table 3 and outside the waveguide 6. The weight detecting means 15 includes a capacitance sensor that detects a change in weight due to the food 4 as a change in capacitance, a distortion sensor that converts weight information into a distortion amount, and a pressure sensor that converts weight information into a pressure change. Alternatively, an optical sensor or the like that detects the amount of movement or change of a predetermined position in a non-contact manner may be used. In this embodiment, a capacitance type sensor is used.
[0033]
The feature of the present embodiment is a structure embodying a turntableless heating cooker 1 provided with a rotating antenna 7 for stirring electromagnetic waves in a gap 2a on the lower surface of the table 3. In order to transmit food information to the weight detecting means 15 via the rotating antenna 7 and the rotating driving means 9 by the food weight supporting member 17 provided at the lower center of the table 3, the rotating shaft 8 of the rotating antenna 7 and the rotating antenna 7 are connected. It has a hollow shaft structure in which a through hole 17d is provided so as to be able to penetrate the rotation driving means 9 for rotational driving.
[0034]
Thereby, the weight information of the food 4 can be directly transmitted to the weight detecting means 15 via the food weight support member 17 provided at the lower center of the table 3 without affecting the installation restriction of the rotating antenna 7. . The food weight supporting member 17 is configured to be in a non-contact structure with the rotating shaft 8 and the rotation driving means 9 so that the weight information of the food 4 can be transmitted to the weight detecting means 15 without loss of information due to a contact friction force or the like. it can.
[0035]
Further, in consideration of the positioning accuracy of the food weight supporting member 17 and stabilization of the assembling property, a bearing (a vertical sliding member) (not shown) is provided inside the rotating shaft 8 or the rotating drive means 9. An information transmission structure in which the loss of information is small by reducing the sliding friction resistance between the bearing and the food weight supporting member 17 may be adopted.
[0036]
Further, the food weight supporting member 17, the rotating antenna 7, and the rotating shaft 8 may be integrated. In this case, the food weight supporting member 17 and the table 3 are in a sliding contact state. The structure of the contact portion may be a pin support structure (not shown) in which the tip of the food weight support member 17 has a curvature to make point contact with the table 3.
[0037]
Further, in consideration of the case where the contact resistance of the contact portion due to the weight of the food 4 is large, a structure in which a sliding member (not shown) is provided at the contact portion between the food weight support member 17 and the table 3 may be adopted.
[0038]
FIG. 3 relates to the detection of the position of the food 4 stored in the heating chamber 2 as information on the food 4, and is a diagram for explaining the principle of detecting the position of the food, which is one embodiment of the present invention. An infrared sensor for detecting temperature information of the food 4 is used as the temperature detecting means 10.
[0039]
FIG. 4 shows a temperature detection by the temperature detection means 10 and a position detection signal, and is a diagram for explaining a food position detection signal process according to an embodiment of the present invention.
[0040]
The position detection of the food 4 according to the present embodiment will be described with reference to FIGS.
[0041]
The installation position of the temperature detecting means 10 in the heating cooker 1 is shown in FIG. The temperature measuring means 10 is installed above the heating chamber 2 so that the food 4 placed on the table 3 in the heating chamber 2 can be detected at any position. , A temperature detection driving means 11 which can be driven biaxially.
[0042]
In this drawing, as one embodiment, a configuration capable of measuring almost the entire surface of the table 3 in the heating chamber 2 is employed, and a plurality of (three in the embodiment, three temperature sensing means 10) temperature sensing means 10 are integrally driven. The position detecting means provided with the uniaxial (rotating) temperature detecting driving means 11 is shown.
[0043]
Here, the three temperature detecting means 10 shown in the present embodiment are referred to as a sensor A, a sensor B, and a sensor C, respectively. In the figure, the measurement trajectory (the range in which the temperature can be detected) of each temperature detecting means 10 when driven by one axis (rotation) is indicated by hatched portions. Needless to say, the number of the temperature measuring means 10 is not limited to three, but may be one, and may be a number in consideration of the detection area of the temperature measuring means 10, the effective area of the table 3 and the like. .
[0044]
Further, the temperature detecting means 10 is not limited to an infrared sensor, and a sensor using inexpensive light such as a photodiode may use light and dark intensity such as reflected light.
[0045]
FIG. 4 shows the output of each temperature detecting means 10 according to the present embodiment when one food 4 is placed on the table 3. The left figure shows the temperature output of each temperature detecting means 10 with respect to the rotation angle of the temperature detecting means 10. As shown in FIG. 3, when the temperature detecting means 10 is scanned by the temperature detecting driving means 11, the food 4 does not exist on the temperature detecting path 21 of the sensor A, and the temperature detecting path 22 of the sensor B and the temperature detecting path 23 of the sensor C are different. Pass over food 4.
[0046]
Here, the placed food 4 is assumed to be frozen food (0 ° C.) before heating in the microwave. Assuming that the temperature on the table 3 in the heating chamber 2 is approximately 20 ° C. at room temperature, the temperature of the food 4 is not detected on the temperature detection locus 21 of the sensor A as shown in FIG. The temperature of the food 4 at the time of passage is detected on the temperature detection locus 22 of the sensor B and the temperature detection locus 23 of the sensor C to pass over the food 4.
[0047]
Here, if a temperature difference occurs when the sensor temperature measurement locus passes over the food 4 with respect to the temperature measurement start temperature (temperature on the table 3) as temperature information of the temperature measurement means 10, as shown in the right figure, The output of each sensor for the position of the food 4 can be obtained.
[0048]
Specifically, the presence or absence of the food 4 may be determined using a certain temperature difference, for example, a temperature difference of 2 or 3 ° C. as a threshold. The position of the food 4 can be estimated from the rotation angle of the temperature detecting means 10 at this time.
[0049]
When there is no difference between the temperature of the food 4 placed and the temperature on the table 3 in the heating chamber 2, heating and cooking is started, and the difference between the temperature rise of the food 4 and the temperature on the table 3 may be used. .
[0050]
The position detection of the food 4 by the temperature detecting means 10 can directly detect the area of the food 4, so that the position can be detected even when a plurality of foods 4 are placed or a large food 4.
[0051]
By performing the rotation control of the rotary antenna 7 based on the obtained position information of the food 4, concentrated heating of the electromagnetic wave becomes possible, and the food 4 can be efficiently cooked.
[0052]
In addition, by performing the target temperature detection by the temperature detection means 10 based on the position information of the food 4, the temperature detection accuracy of the food 4 can be improved without measuring the temperature of a useless area (the area without the food 4). The flow of the heating cooking using the position detection and the position information will be described in detail with reference to FIGS.
[0053]
FIG. 5 shows a flow of heating and cooking based on information of the food 4 which is one embodiment of the present invention shown in FIG. Further, in this embodiment, in particular, there is a difference between the temperature on the table 3 in the heating chamber 2 and the temperature of the food 4 placed thereon.
[0054]
In step 101, the user places the food 4 on the table 3 in the heating chamber 2. Thereafter, when the door (not shown) is closed by a door switch (not shown) or the like, the weight of the food 4 is detected by the weight detecting means 15 in step 102, and the position of the food 4 is detected by the temperature detecting means 10 in step 103. I do. After the position information of the food 4 is detected, the rotation control of the rotary antenna 7 in step 105 and the target temperature measurement of the food 4 in step 106 are performed based on this information.
[0055]
Further, the heating time is calculated and set in step 104 based on the weight information in step 102 and the rotation control information of the rotary antenna 7 in step 105. Then, the electromagnetic heating cooking is started by the magnetron 5 in step 107. During the heating and cooking of the electromagnetic wave, the temperature of the food 4 is constantly monitored by the target temperature measurement of the food 4 by the temperature detecting means 10 in step 108, and when the temperature reaches the target temperature, the heating and cooking in step 109 is stopped.
[0056]
When the heating time set in step 104 has been reached, the cooking in step 109 is automatically stopped. In this embodiment, the cooking is performed by giving priority to the heating time based on the weight of the food 4, and the temperature measurement of the food 4 is for preventing overheating.
[0057]
However, when the food 4 is recognized from the information on the food 4 and the optimum heating / cooking temperature of the food 4 is known, the temperature detection information on the food 4 may be prioritized.
[0058]
Based on the position detection result, rotation control of the rotary antenna 7 in step 105 and target temperature detection of the food 4 by the temperature detection means 10 in step 106 are performed. Further, in this embodiment, the difference between the temperature of the table 3 in the heating chamber 2 and the temperature of the food 4 placed thereon is small, and the position can be detected without any problem even when the discrimination based on the temperature difference cannot be made.
[0059]
As described above, the automatic heating and cooking based on the information of the food 4 enables the appropriate temperature heating and cooking with a simple operation.
[0060]
FIG. 6 shows a flow of heating and cooking based on information of the food 4 which is another embodiment of the present invention shown in FIG. In the present embodiment, the difference between the temperature on the table 3 and the initial temperature of the food 4 placed thereon is small, and it is impossible to make a determination based on the temperature difference.
[0061]
In step 201, the user places the food 4 on the table 3 of the heating chamber 2. Thereafter, the door (not shown) is closed, and at the same time, the weight of the food 4 in step 202 is detected by a signal from a door switch (not shown) or the like. When the weight information of the food 4 is detected, the calculation and setting of the heating time are automatically performed based on the detected information in step 203, and a command for starting the heating cooking from the user (for example, the front panel of the heating cooker (shown in FIG. The electromagnetic wave is output from the magnetron 5 by a warming start switch (not shown) provided in the step (c), and the heating in step 204 is started. At the same time, in step 205, the rotating antenna 7 for stirring the electromagnetic wave into the heating chamber 2 starts rotating at a constant rotation.
[0062]
On the other hand, the temperature measuring means 10 installed at the upper part of the heating chamber 2 starts the temperature measurement of the food 4 while scanning almost the entire area in the heating chamber 2 in step 206. If the temperature of the food 4 rises during the heating and cooking, the difference between the temperature on the table 3 and the temperature of the food 4 occurs, the position of the food 4 is detected in step 207 by the method shown in FIG. At step 208, the temperature measuring means 10 is aimed at the position of the food 4 based on the position information of the food 4 to perform a temperature measurement.
[0063]
In step 209, the electromagnetic wave is concentratedly heated by the rotation control of the rotary antenna 7 based on the position information of the food 4, and at the same time, in step 210, the recalculation and resetting of the heating time in consideration of the rotation control of the rotary antenna 7 are performed. Do. When the set heating time has elapsed, the heating cooker automatically ends the cooking in step 212.
[0064]
In addition, the temperature of the food 4 is constantly monitored by the temperature measurement of the food 4 by the temperature detecting means 10, the temperature of the food 4 is compared with the target temperature of the food 4 in step 211, and when the temperature reaches the target temperature, the heating and cooking in step 212 is stopped.
[0065]
In this embodiment, the cooking is performed by giving priority to the heating time based on the weight of the food 4, and the temperature measurement of the food 4 is for preventing overheating. However, when the food 4 is recognized from the information on the food 4 and the optimum heating / cooking temperature of the food 4 is known, the temperature detection information on the food 4 may be prioritized.
[0066]
Needless to say, by combining the flow of heating and cooking shown in FIGS. 5 and 6 with the initial temperature of the food 4, the optimum heating and cooking of the food 4 can be performed by a simple operation.
[0067]
According to the above embodiment, the weight, temperature, and position information of the food 4 can be detected by the turntableless heating cooker 1 including the weight detection unit 15 and the temperature detection unit 10.
[0068]
In the cooking device 1 provided with the weight detecting means 15 and the temperature detecting means 10, the weight information of the food 4 can be detected by the weight detecting means 15, and the temperature and position information of the food 4 can be detected by the temperature detecting means 10.
[0069]
【The invention's effect】
As described above, according to the present invention, in a heating cooker such as a turntableless microwave oven, it is possible to detect the weight of food placed on a fixed table in a heating chamber, and to detect electromagnetic waves. By controlling the irradiation time and the output, the optimum finishing temperature can be obtained, and it is possible to set the time for automatic heating and cooking.
[0070]
This can shorten the heating time and save energy.
[Brief description of the drawings]
FIG. 1 is a diagram showing a food information detecting means according to an embodiment of the present invention and a cooking device for controlling the heating of foods based on the information.
FIG. 2 is a sectional view showing a food weight detecting means and its peripheral structure in the cooking device according to one embodiment of the present invention.
FIG. 3 is a diagram illustrating a principle of detecting a food position according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a food position detection signal process according to an embodiment of the present invention.
FIG. 5 is a diagram showing a flow of heating and cooking based on food information according to an embodiment of the present invention.
FIG. 6 is a diagram showing a flow of heating and cooking based on food information according to an embodiment of the present invention.
[Explanation of symbols]
1 ... heating cooker 2 ... heating room 3 ... food table (table)
4 Food 5 Magnetron 6 Waveguide 7 Rotating antenna 8 Rotating shaft 9 Rotation driving means 10 Temperature detecting means 12 Heating chamber housing 15 Weight detecting means 16 Control means 17 Food weight supporting member

Claims (1)

A heating chamber (2) for storing the food (4), a magnetron (5) for heating the food (4), a waveguide (6) for guiding electromagnetic waves generated from the magnetron (5) to the heating chamber (2), A heating means including a rotary antenna (7) for stirring electromagnetic waves and a rotary drive means (9) for driving the rotary antenna (7); and a fixed food table (3) for mounting the food (4). In the heating cooker provided with the above, the weight detecting means (15) for detecting the weight information of the food (4) is provided outside the waveguide (6) almost below the center of the fixed food placing table (3). A cooking device characterized by the above-mentioned.

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