JP4649802B2 - Cooker - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heating cooker used in general households.
[0002]
[Prior art]
As a conventional cooking device, for example, an induction heating cooking device is described in JP-A-6-302378. This structure will be described with reference to FIG.
[0003]
A top plate 2 made of a nonmagnetic material is mounted on the upper surface of the main body 1. A cooking container 4 is placed on the top surface of the top plate 2. The cooking container 4 is heated by a heating coil 3 provided below the top plate 2. That is, when a high-frequency current is supplied to the heating coil 3 by the control means 7, the heating coil 3 generates a high-frequency magnetic field, and this high-frequency magnetic field is linked to the bottom surface of the cooking container 4, and the cooking container 4 itself is induction-heated to generate heat. To do. Accordingly, the food stored in the cooking container 4 is heated by the heat generated by the cooking container 4 and cooking proceeds. At this time, the control means 7 adjusts the electric power supplied to the heating coil 3 based on the temperature signal detected by the temperature detection means 6 to control the temperature of the food. At this time, according to the technique disclosed in the above-mentioned document, the temperature detection means 6 is attached to the heat collecting plate 5 to perform accurate temperature control. The heat collecting plate 5 is made of a non-magnetic material and is attached to the lower surface of the top plate 2.
[0004]
[Problems to be solved by the invention]
In the heating cooker having the conventional configuration, the heat collecting plate 5 receives the amount of heat generated by the cooking container 4 via the top plate 2, and the temperature detecting means 6 detects the temperature of the heat collecting plate 5. Therefore, there is a problem that the thermal response is slow. That is, since the top plate 2 is made of an electrical insulator such as ceramic and has a low thermal conductivity, the heat transfer to the heat collecting plate 5 is delayed as described above. There is a delay in detection.
[0005]
[Means for Solving the Problems]
The present invention provides a cooking device capable of detecting the boiling state of an object to be heated in the cooking container by providing vibration detecting means for detecting the vibration of the top plate and detecting the vibration of the cooking container through the top plate. It is said.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, there is provided a top plate for placing a cooking container into which an object to be heated is placed, a heating means for heating the cooking container, and vibration detection for detecting vibration of the cooking container through the top plate. And the boiling state of the heated object is determined by determining that the heated object is in a boiling state when the vibration of the cooking container is reduced after the vibration is generated based on the output of the vibration detecting means. And a boiling detection means. Thereby , generation | occurrence | production of the bubble by boiling is detected by detecting the change of the vibration of a cooking container , and boiling detection can be performed correctly.
[0007]
In the invention described in claim 2, in particular, the vibration detecting means is provided with a heat insulating means between the top plate and the heat detecting means is adapted to block conduction heat from the top plate of the vibration detecting means. It is possible to improve the reliability.
[0008]
In the invention described in claim 3, in particular, the vibration detecting means is provided with vibration transmitting means in contact with the top plate, and the vibration detecting means is separated from the top plate so that the heat insulating effect between the vibration detecting part of the vibration detecting means and the top plate is achieved. Is designed to be larger.
[0009]
In the invention described in claim 4, the vibration detecting means is provided with a holding means that pushes up the top plate by an elastic body such as a spring so that the vibration detecting means reliably contacts the lower surface of the top plate so that the vibration detecting means reliably It is made to be detectable.
[0010]
The invention described in claim 5 eliminates the influence of the frequency noise of the cooling fan and other commercial power supply, particularly by detecting the boiling state of the heated object through a low-frequency cutoff filter that blocks vibration noise. Thus, the boiling state of the object to be heated can be accurately detected.
[0011]
In the invention described in claim 6, in particular, the boiling detection means detects the boiling state of the object to be heated via a high-frequency cutoff filter that blocks vibration noise of about 10 kHz or more from the output of the vibration detection means. In addition, high-frequency vibration noise such as vibration noise of about 20 kHz band that is the frequency of induction heating is removed, and the cooking device can accurately detect the boiling state of the object to be heated.
[0012]
According to the seventh aspect of the present invention, the vibration detecting means is provided with a surrounding heat insulating means for shielding from the ambient temperature so as to reduce the influence of the ambient temperature so that the boiling cooker can accurately detect boiling.
[0013]
According to an eighth aspect of the present invention, the boiling detection means includes a timer means for timing after the output of the vibration detection means reaches a predetermined value or more, and when the time of the timer means reaches a predetermined time, the heating means By stopping heating or reducing the heating output of the heating means, it is possible to reliably control the heating output of the heating means even in a situation where it cannot be distinguished from vibration before boiling and vibration during boiling.
[0014]
According to the ninth aspect of the present invention, the boiling detection means includes a heating output correction means that changes a judgment value of the output of the vibration detection means according to the heating output, so that the boiling state of the object to be heated is changed even if the heating output changes. It is a cooking device that can detect accurately.
[0015]
【Example】
Example 1
The first embodiment of the present invention will be described below. FIG. 1 is a cross-sectional view showing a configuration of an induction heating cooker in the present embodiment. In FIG. 1, reference numeral 21 denotes a cooking container for storing an object to be heated. A top plate 22 made of ceramic which is a non-magnetic material for placing the cooking container 21, and a top plate provided by being provided below the top plate 22. 22, vibration detection means 23 for detecting the vibration of the cooking container 21, boiling detection means 24 for detecting the boiling state of the object to be heated by the output of the vibration detection means 23, a heating coil 25 as heating means, Heating control means 26 for supplying a high frequency current to the heating coil 25 is provided. The heating control means 26 has a function of adjusting the magnitude of the high-frequency current supplied to the heating coil 25 or controlling the power supplied to the heating coil 25.
[0016]
The vibration detection means 23 has a piezoelectric ceramic sensor that contacts the lower surface of the top plate 22, and is configured to detect vibration of the cooking container 21 via the top plate 22. As the vibration detection means 23, the piezoelectric ceramic sensor is used in the present embodiment as described above. However, a mechanical vibration sensor such as a vibration pickup coil can also be used, and is limited to a specific type of sensor. Instead, any device capable of detecting vibrations may be used.
[0017]
Hereinafter, the operation of this embodiment will be described. When a power source (not shown) is turned on and heating is started by an operation switch (not shown), the heating control means 26 supplies a high frequency current to the heating coil 25. When a high frequency current is supplied to the heating coil 25, a high frequency magnetic field is emitted from the heating coil 25, and the cooking vessel 21 on the top plate 22 is induction heated. Due to this induction heating, the temperature of the cooking vessel 21 rises and the object to be heated in the cooking vessel 21 is cooked.
[0018]
As described above, the vibration detector 23 that is in contact with the lower surface of the top plate 22 detects the vibration of the cooking container 21 via the top plate 22. The vibration detected by the vibration detecting means 23 and the change in the water temperature when the object to be heated is water, that is, when boiling water will be described with reference to FIG. In FIG. 2, when heating is started, the temperature of the water in the cooking vessel 21 rises. When heating is continued and the water temperature rises, so-called partial boiling occurs, in which small bubbles are generated from the surface of the cooking vessel 21, and the vibration increases rapidly. Thereafter, when the water temperature reaches the boiling point, a large bubble is generated in the cooking vessel 21, and the vibration becomes smaller than that before the boiling. The boiling detection means 24 can detect boiling in the cooking container 21 by determining the magnitude of the vibration from the output of the vibration detection means 23.
[0019]
As described above, according to the present embodiment, the conventional induction heating cooker has a boiling detection method in which the temperature of the top plate 22 is detected by a thermistor or the like, and is responsive from the low thermal conductivity of the top plate. However, the boiling point in the cooking container 21 can be detected more accurately by detecting the change in the vibration of the cooking container.
[0020]
In addition, after the boiling is detected, the heating control means 26 can reduce unnecessary power by stopping or reducing the power of the heating coil 25. Moreover, it can also be set as a user-friendly cooking device by informing the user of boiling.
[0021]
(Example 2)
Next, a second embodiment of the present invention will be described. FIG. 3 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, in addition to the configuration described in the first embodiment, the vibration detecting unit 23 includes a heat insulating unit 27 made of a heat resistant resin between the top plate 22 and the heat detecting unit 23 to improve the heat resistance of the vibration detecting unit. It is what I did.
[0022]
Because of the above configuration, the lower surface of the top plate 22 is cooled by a fan (not shown). This fan cools the heating coil 25, the power element in the heating control means 26, and the like. The cooling air from the fan also flows on the lower surface of the top plate 22, and the lower surface of the top plate 22 is also cooled. However, the lower surface of the top plate 22 may be as high as about 200 ° C. during cooking using tempura oil, such as when cooking fried food, and the surface with which the vibration detecting means 23 contacts is also in a high temperature state. The heat insulation means 27 is provided between the vibration detection means 23 and the top plate 22 to reduce heat conduction from the top plate 22 and to reduce the temperature rise of the vibration detection means 23. The heat insulating means 27 is made of a heat resistant resin, reduces heat conduction, and transmits vibration. Moreover, the heat insulation effect can be further improved by adopting a shape such as increasing the surface area in order to improve heat dissipation. That is, it is possible to detect the vibration of the cooking vessel 21 by reducing the temperature from the top plate 22 by the heat insulating means 27.
[0023]
As described above, according to the present embodiment, the vibration detecting means 23 suppresses the temperature rise of the vibration detecting means 23 by interposing the heat insulating means 27 made of heat resistant resin between the top plate 22 and the reliability. A cooking device that can detect boiling with high accuracy and accuracy is realized.
[0024]
(Example 3)
Next, a third embodiment of the present invention will be described. FIG. 4 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, the vibration detection means 23 includes vibration transmission means 28 in contact with the top plate 22 so as to detect the boiling state of the object to be heated. The vibration transmitting means 28 is made of a glass material which is in contact with the lower surface of the top plate 22 and is a metal or a non-magnetic material.
[0025]
Since it is set as the above structure, the vibration of the cooking vessel 21 is transmitted to the vibration transmission means 28 via the top plate 22. The vibration transmission means 28 transmits the vibration and transmits it to the vibration detection means 23. That is, the vibration transmitting means can reduce the temperature of the top plate 22 and can be configured such that the attachment position of the vibration detecting means 23 is separated from the high temperature portion on the lower surface of the top plate 22. is there.
[0026]
As described above, according to the present embodiment, the vibration detection means 23 includes the vibration transmission means 28 in contact with the top plate 22 and realizes a cooking device capable of accurately detecting boiling.
[0027]
Example 4
Next, a fourth embodiment of the present invention will be described. FIG. 5 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, the vibration detecting means 23 includes a holding means 29 that is pushed up to the top plate 22 by a spring so as to come into contact with the lower surface of the top plate 22. The holding means 29 is fixed to a part of the casing of the main body (not shown) and is pushed upward by a spring.
[0028]
Hereinafter, the operation of this embodiment will be described. The holding means 29 pushes up the vibration detecting means 23 with a spring. When the top plate 22 is opposed, the vibration detecting means 23 is brought into close contact with the lower surface of the top plate 22 by the pushing force of the spring. The vibration of the top plate 22 can be detected when the vibration detecting means 23 is in close contact.
[0029]
As described above, according to the present embodiment, the vibration detecting means 23 is constituted by the holding means 29 that is pushed up to the top plate 22 by the spring, and comes into contact with the lower surface of the top plate 22 so that the lower surface of the top plate 22 is reliably attached. It is possible to achieve a cooking device that can be in close contact with each other and can accurately detect boiling.
[0030]
(Example 5)
Next, a fifth embodiment of the present invention will be described. FIG. 6 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, the boiling detection means 24 is provided with a low-frequency cutoff filter 30 that removes a vibration component of approximately 1 kHz or less from the output of the vibration detection means 23 so as to detect the boiling state of the object to be heated. is there.
[0031]
The operation of this embodiment will be described below. A cooling fan (not shown) is provided in the main body of the heating cooker. Vibration due to rotation of the fan is about 1 kHz or less and is transmitted to the vibration detecting means 23. There is also a 50/60 Hz frequency band of commercial power used for power. That is, the vibration detection means 23 receives vibration noise due to the rotation frequency of the fan and the frequency of the commercial power supply. The low-frequency cutoff filter 30 has a cutoff frequency set to about 1 kHz so that the vibration noise can be removed, and the low-frequency side vibration noise can be removed. That is, the vibration noise generated when the cooking vessel 21 is boiled can be detected by removing vibration noise on the low frequency side. Based on the signal from which the low frequency band has been removed, the boiling detection means 24 determines the boiling state.
[0032]
As described above, according to the present embodiment, the boiling detection means 24 is provided with the low-pass filter 30 whose output of the vibration detection means 23 is approximately 1 kHz or less to remove the low-frequency vibration noise and It is possible to provide a cooking device capable of accurately detecting boiling by detecting the boiling state.
[0033]
(Example 6)
Next, a sixth embodiment of the present invention will be described. FIG. 7 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, the boiling detection means 24 is provided with a high-frequency cutoff filter 31 that blocks vibration noise of approximately 10 kHz or more from the output of the vibration detection means 23 so as to detect the boiling state of the object to be heated. is there.
[0034]
The operation of this embodiment will be described below. The frequency induced from the heating coil 25 is about 20 kHz, and the cooking vessel 21 is heated by this induced magnetic flux. The cooking vessel 21 vibrates at the induction heating frequency, and when detecting boiling, it is necessary to remove the induction heating frequency band. The cut-off frequency of the high-pass filter 31 is set to approximately 10 kHz, and the approximately 20 kHz band that is the frequency of the induction heating can be removed. That is, the vibration caused when the cooking vessel 21 is boiled can be detected by removing the vibration caused by induction heating. Based on the signal from which this induction heating frequency band has been removed, the boiling detection means 24 determines the boiling state.
[0035]
As described above, according to the present embodiment, the boiling detection means 24 is provided with the high-frequency cutoff filter 31 that cuts off the high frequency noise of about 10 kHz or more from the output of the vibration detection means 23 to detect the vibration generated during the boiling. A cooking device capable of detecting an accurate boiling state of an object to be heated is realized.
[0036]
(Example 7)
Next, a seventh embodiment of the present invention will be described. FIG. 8 is a cross-sectional view showing the configuration of this embodiment. In the present embodiment, the vibration detection means 23 includes an ambient heat insulation means 32 that shields from the ambient temperature so as to reduce the influence of the ambient temperature.
[0037]
The operation of this embodiment will be described below. The vibration detecting means 23 composed of a piezoelectric ceramic sensor detects vibration by converting vibration into an electric signal by the piezoelectric effect of ceramics. The piezoelectric ceramic sensor has the piezoelectric effect and also has a pyroelectric effect in which electric charges are generated by heat. This pyroelectric effect is generated when heat is applied to the piezoelectric ceramic, and an electrical signal that is not vibration is output. In addition, the capacitor capacity of the piezoelectric ceramic sensor changes with the ambient temperature and affects the detection accuracy of the electric signal. That is, the surrounding heat insulating means 32 is configured to shield the surroundings of the vibration detecting means 23, thereby reducing the influence of the ambient temperature and reliably detecting vibration due to boiling.
[0038]
As described above, according to the present embodiment, the vibration detection means 23 includes the ambient heat insulation means 32 that shields from the ambient temperature, and can accurately detect boiling by reducing the influence of the ambient temperature. is there.
[0039]
(Example 8)
Next, an eighth embodiment of the present invention will be described. FIG. 9 is a cross-sectional view showing the configuration of the present embodiment. In the present embodiment, the boiling detection means 24 includes a timer means 33 that counts after the output of the vibration detection means 23 reaches a predetermined value or more, and stops heating after a predetermined time or reduces heating. Is.
[0040]
The operation of this embodiment will be described below. The vibration is maximized at the time of partial boiling before boiling. If this vibration is equal to or greater than a predetermined value, the timer means 33 starts counting. When the predetermined count is reached, a signal is transmitted to the heating control means 26 to control the amount of heating to the heating coil 25 and stop heating or reduce the amount of heating. That is, even when the vibration before boiling and the vibration at the time of boiling cannot be distinguished, the heating can be controlled with certainty and the boiling can be detected more reliably.
[0041]
As described above, according to the present embodiment, the boiling detection unit 24 includes the timer unit 33 that counts after the output of the vibration detection unit 23 becomes equal to or higher than a predetermined value, and stops heating after a predetermined time. Thus, a cooking device capable of more accurate boiling detection can be realized.
[0042]
Example 9
Next, a ninth embodiment of the invention will be described. FIG. 10 is a cross-sectional view showing the configuration of the present embodiment. In this embodiment, the boiling detection means 24 includes a heating output correction means 34 that changes the determination value of the output of the vibration detection means 23 in accordance with the heating output, and detects the boiling state of the object to be heated. .
[0043]
The operation of this embodiment will be described below. The heating control means 26 controls the heating output. The magnitude of vibration during boiling is related to the magnitude of the heating output. When the heating output is small, bubbles are gently generated and the vibration is slightly small. In addition, when the heating output is large, large bubbles are generated vigorously and vibration is increased. That is, the magnitude of vibration changes depending on the magnitude of the heating output. The heating output correcting means 34 receives the heating output signal from the heating control means 26 and changes the judgment value. By changing this determination value according to the heating output, even if the heating output changes, boiling detection can be accurately performed.
[0044]
As described above, according to the present embodiment, the boiling detection means 24 includes the heating output correction means 34 that changes the determination value of the output of the vibration detection means 23 in accordance with the heating output, so that the boiling state of the object to be heated is further increased. It realizes a cooking device that can be detected accurately.
[0045]
【The invention's effect】
As described above, according to the first aspect of the present invention, as a configuration for detecting a change in the vibration of the cooking container via the top plate, a cooking device capable of accurately detecting boiling is realized.
[0046]
According to the second aspect of the present invention, the vibration detecting means comprises a heat insulating means made of a heat resistant resin between the top plate and the heat detecting means so as to improve the heat resistance of the vibration detecting means so that accurate boiling is achieved. It realizes a cooking device that can detect.
[0047]
According to the third aspect of the present invention, a cooking device capable of accurately detecting boiling is realized by the vibration transmitting means in contact with the top plate.
[0048]
According to the fourth aspect of the present invention, the holding means that pushes up the top plate by the spring can surely adhere to the lower surface of the top plate.
[0049]
According to the fifth aspect of the present invention, it is possible to provide a cooking device capable of accurately detecting boiling by removing the low-frequency vibration noise and detecting the boiling state of the object to be heated.
[0050]
According to the sixth aspect of the present invention, a cooking device capable of detecting the vibration generated at the time of boiling by the high-pass filter and detecting the boiling state of the object to be heated accurately is realized.
[0051]
According to the seventh aspect of the present invention, it is possible to accurately detect boiling by providing an ambient heat insulating means for shielding from the ambient temperature so as to reduce the influence of the ambient temperature.
[0052]
According to the eighth aspect of the present invention, a cooking device that can detect boiling more accurately is realized by detecting the vibration of a predetermined value or more and then measuring and stopping heating after a predetermined time or reducing the heating. It can be done.
[0053]
According to the ninth aspect of the present invention, a cooking device capable of more accurately detecting the boiling state of the object to be heated is realized by changing the determination value according to the heating output.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a cooking device according to a first embodiment of the present invention. FIG. 2 is a diagram showing a change with time of vibration of the cooking device according to the first embodiment. FIG. 4 is a cross-sectional view showing the structure of a heating cooker according to the second embodiment. FIG. 4 is a cross-sectional view showing the structure of a heating cooker according to the third embodiment. FIG. 6 is a cross-sectional view showing a configuration of a heating cooker according to a fifth embodiment. FIG. 7 is a cross-sectional view showing a configuration of a heating cooker according to a fifth embodiment. FIG. 8 is a cross-sectional view showing the configuration of the cooking device according to the seventh embodiment. FIG. 9 is a cross-sectional view showing the configuration of the cooking device according to the eighth embodiment. FIG. 10 is a cross-sectional view showing the configuration of a cooking device according to a ninth embodiment. FIG. 11 is a cross-sectional view showing the configuration of a cooking device according to a conventional example.
DESCRIPTION OF SYMBOLS 21 Cooking container 22 Top plate 23 Vibration detection means 24 Boiling detection means 25 Heating coil 26 Heating control means 27 Heat insulation means 28 Vibration transmission means 29 Holding means 30 Low-pass filter 31 High-pass filter 32 Surrounding heat insulation means 33 Timer means 34 Heating output correction means

Claims (9)

A top plate for placing a cooking container into which an object to be heated is placed, a heating means for heating the cooking container, a vibration detecting means for detecting vibrations of the cooking container via the top plate, and an output of the vibration detecting means the basis, heating the object to be heated when the vibration is reduced after the generation of the cooking container and a boiling detection means for detecting the boiling state of more the object to be heated to determined to be in a boiling state Cooking device.   The cooking device according to claim 1, wherein the vibration detection means includes a heat insulation means between the vibration detection means and the top plate.   The cooking device according to claim 1 or 2, wherein the vibration detection means includes vibration transmission means in contact with the top plate.   The cooking device according to any one of claims 1 to 3, wherein the vibration detecting means is in contact with the lower surface of the top plate by a holding means that is urged by an elastic force and pushed up to the top plate.   The boiling detection means detects the boiling state of the object to be heated through a low-frequency cutoff filter that blocks vibration noise of approximately 1 kHz or less from the output of the vibration detection means. Cooking cooker.   The boiling detection means detects the boiling state of the object to be heated through a high-frequency cutoff filter that blocks vibration noise of about 10 kHz or more from the output of the vibration detection means. Cooking cooker.   The cooking device according to any one of claims 1 to 6, further comprising ambient heat insulating means for insulating the vibration detecting means from ambient temperature.   The boiling detection means includes timer means for timing after the output of the vibration detection means reaches a predetermined value or more, and stops heating by the heating means when the time of the timer means reaches a predetermined time or heating of the heating means The cooking device according to any one of claims 1 to 7, wherein the output is reduced.   The boiling detection means includes a heating output correction means that changes a determination value of the output of the vibration detection means according to the heating output of the heating means, and detects the boiling state of the object to be heated. The cooking device described.

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