JP2005093122A - Heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating cooker capable of providing a targeted finish state in a short time. <P>SOLUTION: Since an external temperature sensor 29 is fixed to a cooking utensil 3 without being influenced by a magnetic field from an IH coil 10 or without interlaying a top plate 2, and a cooking content is controlled based on wireless communication of temperature information according to the detection result of the temperature sensor 29, the actual temperature of the cooking utensil 3 can accurately be detected without executing gradual lowering control of heating power. Thereby, since the cooking utensil 3 can continuously be heated with high heating power, a cooking object can be cooked in a targeted state in a short time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heating cooker configured to cook the contents of a cooking utensil based on heating the cooking utensil by a heating means.

As shown in FIG. 17, the heating cooker has a configuration in which the thermistor 102 is disposed on the inner peripheral portion of the IH coil 101 and the surface temperature of the cooking utensil 103 is indirectly detected via the top plate 104. is there. In this configuration, when performing automatic boiling cooking, the thermal power is gradually reduced to high, medium and low as the detected temperature of the thermistor 102 increases, and the temporal temperature change rate in the low thermal power state becomes the judgment value. The boiling of water is detected on the basis of the fact that it becomes smaller.
JP 2003-139385 A

In the case of the above-mentioned cooking device, the cooking time is prolonged because the step-down control of the thermal power is performed. The stepwise lowering control of the thermal power is aimed at detecting the actual temperature of the cooking utensil 103 with high accuracy as shown in the following 1) to 3). When it is abolished, the actual temperature of the cooking utensil 103 cannot be detected with high accuracy, and the desired finished state cannot be obtained.
1) Since the lead wire 105 of the thermistor 102 is induction-heated under the influence of the magnetic field from the IH coil 101, the detected temperature of the thermistor 102 becomes higher than the actual temperature. For this reason, the influence of the magnetic field received by the lead wire 105 is reduced by gradually reducing the thermal power, and the detected temperature is brought close to the actual temperature.
2) Since the top plate 104, which is a product of a temperature gradient, exists between the cooking utensil 103 and the thermistor 102, the temperature detected by the thermistor 102 follows the actual temperature when the cooking utensil 103 is continuously heated with high heating power. It is hard to do. For this reason, the heating power of the cooking utensil 103 is actively delayed by weakening the heating power step by step, and the detected temperature is made to follow the actual temperature with high accuracy.
3) When the cooking utensil 103 is continuously heated at a high heating power, the actual temperature of the cooking utensil 103 rises at the same temperature change rate as before the boiling after reaching the boiling temperature, so the temperature change rate falls below the judgment value. In this state, the water temperature reaches 120 ° C. exceeding 100 ° C. For this reason, the actual temperature is converged to the vicinity of the boiling temperature by gradually decreasing the thermal power, and the temperature change rate is reduced when the actual temperature reaches the boiling temperature.
This invention is made | formed in view of the said situation, The objective is to provide the heating cooker which can obtain the target finishing state in a short time.

<About the Invention of Claim 1>
The invention according to claim 1 is provided with a temperature detecting means and a transmitting means in the cooking utensil, and heating means based on wirelessly transmitting temperature information corresponding to the detection result of the temperature detecting means from the transmitting means to the stationary receiving means. The meanings of main terms are as follows.
1) Support means: A dedicated cooking utensil having a temperature detection means and a transmission means can be mechanically supported. The temperature detection means is mechanically connected to the cooking utensil and detects the temperature of the cooking utensil and outputs an electrical signal. This temperature detection means is preferably arranged on the side surface of the cooking utensil from the viewpoint of maintaining the placing property of the cooking utensil with respect to the support means, and the temperature detection means is arranged at the lower end of the cooking utensil in terms of enhancing the temperature detection of the contents. preferable. The transmission means is mechanically connected to the cooking utensil and wirelessly transmits temperature information corresponding to the detection result of the temperature detection means. This temperature information refers to the information about the temperature of the cooking utensil obtained based on the detection result of the temperature detecting means, and the relative temperature etc. relative to the absolute temperature / reference value of the cooking utensil is the temperature information. It corresponds to.
2) Receiving means: receiving temperature information transmitted wirelessly from the transmitting means of the cooking utensil. As these transmitting means and receiving means, communication is possible when the cooking utensil is within the setting area of the supporting means, and communication is possible when the cooking utensil is outside of the setting area of the supporting means. It is preferable to use an incapable state.
3) Control means: The cooking contents are controlled based on driving control of the heating means. Specifically, the inverter circuit that converts the DC power source to the high frequency power source is controlled to switch from the inverter circuit to the heating means. It is preferable to control the amount of power applied. This control means controls the heating means based on the reception result of the receiving means, and the cooking content is controlled based on the directly detected temperature of the cooking utensil.
<About the invention according to claim 2>
According to a second aspect of the present invention, power is supplied wirelessly from the stationary receiving means to the cooking utensil transmitting means. This power supply is preferably performed only during cooking. Specifically, it is preferable to start and stop the supply in conjunction with the start and end of heating.
<About the invention according to claim 3>
According to a third aspect of the present invention, the transmission means transmits temperature information based on amplitude modulation of the power carrier signal from the reception means.
<About the invention according to claim 4>
The invention according to claim 4 transmits the temperature value of the cooking utensil as temperature information from the transmission unit on the cooking utensil side to the receiving unit on the stationary side.
<About the invention according to claim 5>
The invention according to claim 5 wirelessly calls transmission of temperature information from the receiving means on the stationary side to the transmitting means on the cooking utensil side. Specifically, a temperature information request signal is transmitted from the stationary side receiving means to the cooking utensil side transmitting means, and the cooking utensil side transmitting means receives the request signal and returns the stationary side receiving means and temperature information. Is. That is, the stationary side receiving means corresponds to the first transmitting / receiving means functioning as the subject, and the cooking utensil side transmitting means corresponds to the second transmitting / receiving means functioning as the object.
<About the Invention of Claim 6>
In the invention according to claim 6, the transmission means on the cooking utensil side oscillates with the carrier signal synchronized with the internal operating frequency as the temperature information, and the synchronization is the same frequency as the carrier signal or a frequency corresponding to an integer of the carrier signal. Is called.
<About the Invention of Claim 7>
According to the seventh aspect of the present invention, the power carrier signal is transmitted from the power transmitting antenna of the receiving means to the power receiving antenna of the transmitting means, and the temperature information is transmitted from the information transmitting antenna of the transmitting means to the information receiving antenna of the receiving means. The carrier signal for transmission is transmitted. That is, two types of signals, ie, a power dedicated signal and a temperature information dedicated signal are used as carrier signals.
<About the invention according to claim 8>
The invention according to claim 8 uses power carrier signals and temperature information carrier signals having different frequencies.

According to the first aspect of the present invention, the temperature detecting means is provided in the cooking utensil which is not adversely affected by the heating means and does not include the product of the temperature gradient, and the temperature information corresponding to the detection result of the temperature detecting means is wirelessly communicated. Since the cooking content is controlled based on the above, the actual temperature of the cooking utensil can be detected with high accuracy without performing stepwise lowering control of the thermal power. For this reason, since the cooking utensil can be continuously heated with a high heating power, it becomes possible to finish the cooked product in a desired state in a short time.
According to the second aspect of the present invention, since power is supplied wirelessly from the stationary-side receiving means to the transmitting device on the cooking utensil side, there is no need to mount a power source on the cooking utensil side. This eliminates the need to replace and charge the power source, improving usability.
According to the invention of claim 3, the temperature information is transmitted based on the amplitude modulation of the power carrier signal by the transmission means on the cooking utensil side. This eliminates the need to mount a carrier signal oscillation circuit on the cooking utensil side, thereby suppressing an increase in the size of the transmission means.
According to the invention which concerns on Claim 4, the temperature value of the cooking utensil was transmitted as temperature information from the transmission means at the cooking utensil side to the receiving means at the stationary side. For this reason, since the use range of temperature information spreads compared with the case where relative values such as high and low are transmitted as temperature information, various types of cooking can be performed based on wireless information.
According to the invention which concerns on Claim 5, the transmission of temperature information was called by radio | wireless from the receiving means on the stationary side to the transmission means on the cooking utensil side. For this reason, when temperature information is transmitted based on amplitude modulation of a power carrier signal, amplitude modulation only needs to be performed when responding to an interrogation, so that power consumption can be reduced.
According to the invention which concerns on Claim 6, the carrier signal which synchronizes with an operating frequency was oscillated as temperature information from the transmission means by the side of a cooking utensil. For this reason, since the operating frequency can be generated by dividing the carrier signal for temperature information, an oscillation circuit for the operating frequency becomes unnecessary.
According to the seventh aspect of the invention, since two types of signals, ie, a power dedicated signal and a temperature information dedicated signal are used as carrier signals, it is not necessary to transmit temperature information based on amplitude modulation of the power carrier signal. . For this reason, the use efficiency of the carrier signal for power increases, and it becomes possible to stably generate a large drive power supply. Therefore, when using a microcomputer as a transmission means on the cooking utensil side, it is advantageous in terms of power supply. Become.
According to the eighth aspect of the present invention, power carrier signals and temperature information carrier signals having different frequencies are used. For this reason, it always oscillates a relative long wave with high tolerance under the Radio Law as a carrier signal for power, and a relative short wave with low tolerance under the Radio Law as a carrier signal for temperature information only when necessary. It can oscillate.

  The temperature detecting means and the communication means are fixed to the cooking utensil, and the communication means on the cooking utensil side is magnetically coupled to the communication means on the stationary side based on the setting of the cooking utensil within a preset communicable area. . Then, driving power is supplied in a non-contact manner from the communication means on the cooking appliance side to the communication means on the cooking appliance side, and the communication means on the stationary side obtains direct temperature information of the cooking appliance from the communication means on the cooking appliance side in a non-contact manner. Control the cooking content based on what you do. Hereinafter, specific examples of the embodiment will be described with reference to the drawings.

  A top plate 2 made of heat-resistant glass is fixed to the upper surface of the system kitchen 1 as shown in FIG. The top plate 2 corresponds to support means, and a circular heating mark (not shown) is formed on the top plate 2. As shown in FIG. 1, the heating mark functions as a mark for displaying a setting area on which the dedicated cooking utensil 3 and a general-purpose cooking utensil are placed, on the lower surface side of the top plate 2. As shown in FIG. 8, the cabinet 4 is fixed inside the system kitchen 1, and the operation unit 5 is mounted on the front surface of the cabinet 4. The operation unit 5 corresponds to an input means for inputting cooking conditions such as thermal power, and has an automatic water heater key 6, a thermal power adjustment dial 7, and a tempura key 8.

  As shown in FIG. 1, a coil base 9 is housed inside the cabinet 4 so as to be positioned below the heating mark, and an induction heating IH coil 10 corresponding to a heating means is provided on the upper surface of the coil base 9. Is fixed. An internal temperature sensor 11 corresponding to internal temperature detection means is housed inside the cabinet 4. The internal temperature sensor 11 is disposed on the inner periphery of the IH coil 10 and is pressed against the lower surface of the top plate 2 by the spring force of a sensor spring (not shown). The internal temperature sensor 11 is composed of a thermistor, and indirectly detects the surface temperature of the dedicated cooking utensil 3 and the surface temperature of a general-purpose cooking utensil via the top plate 2.

  As shown in FIG. 3, a rectifier circuit 12 is housed inside the cabinet 4, and a commercial AC power supply 13 is connected to an input terminal of the rectifier circuit 12. This rectifier circuit 12 converts an AC power supply 13 into a DC power supply, and is composed of a bridge circuit formed by bridge-connecting diodes and a smoothing capacitor. An inverter circuit 14 is connected to the output terminal of the rectifier circuit 12. The inverter circuit 14 converts a DC power source from the rectifier circuit 12 into a high-frequency voltage, and is mainly composed of switching elements connected in a half-bridge form. An IH coil 10 is connected to the output terminal of the inverter circuit 14, and the IH coil 10 induction-heats the upper cooking utensil 3 based on the application of a high-frequency current from the inverter circuit 14.

  An inverter control unit 15 is accommodated in the cabinet 4. The inverter control unit 15 performs switching control of the inverter circuit 14 and is configured as follows. The control circuit 16 is composed mainly of a microcomputer, and has a CPU, a ROM, a RAM, and an I / O. The operation unit 5 is electrically connected to the input terminal of the control circuit 16, and the control circuit 16 sets cooking conditions according to the operation content of the operation unit 5, and drives signals based on the cooking condition setting results. Is generated. A drive circuit 17 is connected to the control circuit 16. The drive circuit 17 performs switching control of the inverter circuit 14 based on a drive signal from the control circuit 16, and cooks based on flowing a high-frequency current through the IH coil 10. The appliance 3 is induction heated. The control circuit 16 corresponds to control means.

  A temperature detection circuit 18 is connected to the internal temperature sensor 11 via a lead wire. The temperature detection circuit 18 outputs a voltage signal at a level corresponding to the resistance change of the internal temperature sensor 11, and the control circuit 16 is dedicated based on A / D conversion of the voltage signal from the temperature detection circuit 18. The surface temperature T of the cooking utensil 3 and the surface temperature of a general-purpose cooking utensil are indirectly detected, and the pulse width of the drive signal is controlled based on the detection result of the surface temperature.

  The current transformer 19 functions as current detection means for detecting the input current Iin supplied from the AC power supply 13 to the rectifier circuit 12, and the input current detection circuit 20 is connected to the current transformer 19. The input current detection circuit 20 outputs a voltage signal at a level corresponding to the input current Iin, and the control circuit 16 converts the voltage signal from the input current detection circuit 20 from A / D conversion to the input current Iin. Is detected.

  The control circuit 16 detects the amount of electric energy used for induction heating based on temporal integration of the detection result of the input current Iin, and the detection result of the electric energy amount and the detection result of the surface temperature are detected by software. Heating information is obtained based on the processing. The detection result of the surface temperature corresponds to the consumption result of electrical energy, and the control circuit 16 determines the weight of the material / content of the dedicated cooking utensil 3 and the general-purpose cooking utensil based on the correlation between the two. Obtained as heating information, and the pulse width of the drive signal is controlled based on the result of obtaining the heating information.

  An R / W unit 21 is connected to the control circuit 16. The R / W unit 21 performs serial communication with the control circuit 16 and corresponds to a receiving unit and a transmitting / receiving unit. As shown in FIG. 2, the R / W unit 21 includes an oscillation circuit 22, a modulation circuit 23, a resonance circuit 24, an antenna drive circuit 25, and a demodulation circuit 26. The oscillation circuit 22 is supplied from a DC power source. The energy is converted into an oscillation signal having a constant frequency (specifically, 13.56 MHz). The modulation circuit 23 amplitude-modulates the oscillation signal from the oscillation circuit 22. In this amplitude modulation, an oscillation signal having a normal amplitude is changed to an amplitude of 80% with a modulation period of “1.2 μsec (847 kHz)”, and the control circuit 16 changes the modulation circuit 23 every set time (specifically, every 1 sec). ) Periodically oscillates the oscillation signal from the transmission circuit 22.

  The resonance circuit 24 is composed of a transmission / reception antenna coil 27 and a resonance capacitor 28, and the antenna drive circuit 25 drives the antenna coil 27 based on an oscillation signal from the modulation circuit 23 and converts the antenna coil 27 into a transmission signal. A corresponding carrier signal is transmitted. That is, the carrier signal is amplitude-modulated every 1 sec when the modulation circuit 23 amplitude-modulates the oscillation signal, and is oscillated as a data request signal in the data length format.

  FIG. 4A shows the current waveform of the data request signal oscillated from the antenna coil 27. The data request signal is composed of a start bit SB, a data bit DB, and an end bit EB. The start bit SB and the end bit EB are obtained by modulating the carrier signal to an amplitude of 80% by three modulation periods, and function as a transmission start signal for signaling the start of transmission of the data bit DB and a transmission end signal for signaling the end of transmission. . The data bit DB functions as a request signal for requesting a return of temperature information, and has a data length of 8 bits (specifically, “01011001”). The inverter control unit 15 is configured as described above.

  As shown in FIG. 1, an external temperature sensor 29 corresponding to the temperature detection means and the external temperature detection means is mechanically fixed to the side surface of the dedicated cooking utensil 3. The temperature sensing part is in close contact with the side surface of the lower part of the cooking utensil 3. The external temperature sensor 29 is a thermistor that directly detects the surface temperature To of the cooking utensil 3, and the external temperature sensor 29 is electrically connected to a tag portion 30 corresponding to a transmitting means via a lead wire 31. It is connected. The tag unit 30 detects the temperature signal from the external temperature sensor 29 based on the electric power supplied from the R / W unit 21 in a non-contact manner, and the temperature corresponding to the detection result of the temperature signal in the R / W unit 21. Information is transmitted in a non-contact manner, and is configured as follows.

  As shown in FIG. 2, the resonance circuit 32 includes a transmission / reception antenna coil 33 and a resonance capacitor 34. The resonance frequency of the resonance circuit 32 is set equal to the resonance frequency of the R / W unit 21, and the antenna coil 33 of the resonance circuit 32 is based on placing the cooking utensil 3 on the heating mark of the top plate 2. A carrier signal that is magnetically coupled to the antenna coil 27 of the R / W unit 21 and oscillated from the antenna coil 27 of the R / W unit 21 is received magnetically. The heating mark on the top plate 2 functions as a mark for magnetically coupling / blocking between the antenna coil 27 and the antenna coil 33. When the cooking utensil 3 is not present on the heating mark, the antenna coil 27 and the antenna coil 33 are used. The gap is magnetically interrupted.

  The rectifier circuit 35 rectifies the carrier signal from the resonance circuit 32, and the power supply circuit 36 generates a 3V drive power supply for the tag unit 30 based on the rectified output from the rectifier circuit 35. FIG. 4B shows the rectified output Vrec-o from the rectifier circuit 35, and the rectified output Vrec-o varies to 5V-6V. FIG. 4C shows the drive power supply Vdd generated by the power supply circuit 36. The power supply circuit 36 stabilizes the rectified output Vrec-o to a constant voltage power supply Vdd of 3V.

  As shown in FIG. 2, the comparison circuit 37 compares the temperature signal from the external temperature sensor 29 with the reference signal from the control temperature setting circuit 38, and generates a signal corresponding to the comparison result between the two. The control temperature setting circuit 38 outputs a boiling water recognition temperature Tb corresponding to 100 ° C. of water as a reference signal, and the comparison circuit 37 compares the direct surface temperature To of the cooking utensil 3 with the boiling water recognition temperature Tb. , “Surface temperature To <recognition temperature Tb” and “surface temperature To ≧ recognition temperature Tb” are identified. Reference numeral 39 denotes an external temperature detection unit including a comparison circuit 37 and a control temperature setting circuit 38.

  The memory 40 corresponds to a storage means for storing response data, and is composed of an EEPROM. This response data serves as a base for responding to a data request signal from the R / W unit 21, and two types of response data are set: hot water continuation data and hot water completion data. The hot water continuation data and the hot water completion data are in the data length format. As shown in FIG. 5A, the hot water continuation data is representatively generated, and the start data DS and the data bit DB for generating the start bit SB are generated. Temperature data DO to be generated and end data to generate an end bit EB. The temperature data DO indicates the relative temperature of the high and low, and the temperature data DO of the boiling water continuation data is composed of 8-bit data specifying that “the surface temperature To of the cooking utensil 3 <the boiling water recognition temperature Tb”, The temperature data DO of the hot water completion data is composed of 8-bit data specifying that “the surface temperature To of the cooking utensil 3 ≧ the hot water recognition temperature Tb”.

  As shown in FIG. 2, the carrier synchronization detection circuit 41 detects the carrier signal from the resonance circuit 32 in synchronization, and the demodulation circuit 42 detects R based on the detection of the carrier signal from the carrier synchronization detection circuit 41. The data request signal from the / W unit 21 is received. The modulation circuit 43 detects response data corresponding to the comparison result of the comparison circuit 37 from the memory 40, and generates a drive signal corresponding to the detection result of the response data. The modulation circuit 43 is provided with the reception result of the data request signal from the demodulation circuit 42, and the drive signal is generated every 1 sec when the data request signal is received.

  FIG. 5B shows a drive signal generated by the modulation circuit 43 based on the boiling data, and the comparison circuit 37 identifies “the surface temperature To of the cooking utensil 3 <the boiling recognition temperature Tb”. Sometimes, the hot water continuation data is detected from the memory 40, and a drive signal is generated based on the hot water continuation data. Further, when the comparison circuit 37 has identified “the surface temperature To of the cooking utensil 3 ≧ the recognition temperature Tb of the boiling water”, the boiling water completion data is detected from the memory 40, and a drive signal is generated based on the boiling water completion data.

  As shown in FIG. 2, the load change circuit 44 is mainly composed of transistors, and the modulation circuit 43 controls the load change circuit 44 on and off based on a drive signal. The resistor 45 corresponds to the load of the antenna coil 33 and is switched between the invalid state and the valid state based on the on / off of the load changing circuit 44. In the invalid state and the valid state of the resistor 45, the inductance of the antenna coil 33 changes relatively, and the amplitude of the current flowing through the antenna coil 27 of the R / W unit 21 changes. The resonance circuit 32, rectifier circuit 35, power supply circuit 36, memory 40, carrier synchronization detection circuit 41, demodulation circuit 42, modulation circuit 43, load change circuit 44, and load 45 are constituted by a transmission / reception dedicated IC 46. The dedicated IC 46 refers to a single integrated circuit that exhibits a transmission / reception function without using a microcomputer.

  The demodulation circuit 26 of the R / W unit 21 shapes the current flowing through the antenna coil 27 and outputs the waveform to the control circuit 16. The control circuit 16 converts the response content from the tag unit 30 into the detection signal from the demodulation circuit 26. Recognize based on. FIGS. 5C and 6 show current waveforms flowing in the antenna coil 27. FIG. 5C shows current waveforms when hot water is generated as temperature information from the tag unit 30 and continuous data is oscillated. FIG. 6 shows a current waveform when hot water completion data is oscillated from the tag unit 30 as temperature information. That is, the R / W unit 21 periodically transmits a request signal for temperature information to the tag unit 30 by radio. In response to a request signal from the R / W unit 21, the tag unit 30 periodically returns temperature information wirelessly. As the temperature information, the direct surface temperature To of the cooking utensil 3 is heated and recognized temperature Tb. Either the hot water continuation data indicating that the temperature has not reached the temperature or the hot water completion data indicating that the direct surface temperature To of the cooking utensil 3 has reached the hot water recognition temperature Tb is selectively returned.

An operation control program is recorded in the ROM of the control circuit 16, and the CPU of the control circuit 16 performs cooking by controlling the drive of the IH coil 10 based on the operation control program. Hereinafter, the control contents of the control circuit 16 when the automatic water heater key 6 is operated will be described.
When the control circuit 16 detects that the automatic water heating key 6 has been operated, the heating power is set to the rated value of 3 kW in step S1 of FIG. 7, and the automatic water heating cooking is started with the heating power of 3 kW. This heating power is adjusted based on controlling the energization time per unit time of the IH coil 10 by the on / off ratio of the inverter circuit 14, and the control circuit 16 starts automatic water heating cooking with a high power of 3 kW. In step S2, power transmission to the R / W unit 21 is started. Then, oscillation of the carrier signal is started based on activation of the R / W unit 21, and activation is performed based on reception of the carrier signal by the tag unit 30 and generation of power.

  In step S3, the control circuit 16 modulates the carrier signal based on driving control of the modulation circuit 23 of the R / W unit 21. Then, a data request signal is oscillated from the antenna coil 27 of the R / W unit 21, and the presence / absence of temperature information from the tag unit 30 is determined via the demodulation circuit 26 of the R / W unit 21 in step S4. For example, when it is detected that the temperature information is not output from the demodulation circuit 26, it is recognized that a general-purpose cooking utensil having no wireless communication function is set on the heating mark of the top plate 2, and general-purpose automatic kettle cooking is performed. Execute. FIG. 10 shows the contents of general-purpose automatic water cooking, and the control circuit 16 gradually reduces the heating power to 3 kW, 2 kW, and 1 kW based on the output signal from the internal temperature sensor 11 to step the heating state of the cooking utensil. Change. Hereinafter, the contents of general-purpose automatic water heating cooking will be described.

  When the control circuit 16 detects that the temperature information is not output from the demodulation circuit 26 in step S4 of FIG. 7, the control circuit 16 indirectly detects the cooking utensil based on acquiring the output signal from the internal temperature sensor 11 in a wired manner in step S5. The surface temperature T is detected, and the detection result of the surface temperature T is compared with the determination value T1 in step S6. This determination value T1 is recorded in advance in the ROM of the control circuit 16. When the control circuit 16 detects “T> T1” in step S6, the heating power is reduced from 3 kW to 2 kW in step S7, and the IH coil 10 is turned off. Operate continuously with 2kW of thermal power.

  When the control circuit 16 proceeds to step S8, the indirect surface temperature T of the cooking utensil is detected based on the output signal from the internal temperature sensor 11. And it transfers to step S9 and the detection result of indirect surface temperature T is compared with determination value T2 (> T1). This determination value T2 is recorded in advance in the ROM of the control circuit 16. When the control circuit 16 detects “T> T2” in step S9, the heating power is lowered from 2 kW to 1 kW in step S10, and the IH coil 10 is turned off. Operate continuously with 1kW of thermal power.

  When the control circuit 16 proceeds to step S11, it detects the indirect surface temperature T of the cooking utensil based on the output signal from the internal temperature sensor 11, and proceeds to step S12. The detection process of the surface temperature T is periodically performed every set time (specifically, every 1 sec). When the control circuit 16 detects the surface temperature T, the current detection of the surface temperature T is performed in step S12. A temporal change rate ΔT is calculated from the difference between the result and the previous detection result.

  In step S13, the control circuit 16 compares the calculation result of the change rate ΔT with the determination value ΔTb. This determination value ΔTb is recorded in advance in the ROM of the control circuit 16. When the control circuit 16 detects “ΔT <ΔTb” in step S13, it determines that the cooking utensil has reached the recognition temperature Tb by boiling, The process proceeds to the heat retention process of S14. Here, the thermal power is lowered from 1 kW to the heat insulation value, and the thermal power is adjusted in the vicinity of the heat insulation value so that the indirect surface temperature T of the cooking utensil is heated to the recognition temperature Tb. That is, when there is no response to the data request signal from the R / W unit 21, it is determined that a general-purpose cooking utensil is used, and cooking progress is controlled based on the indirect surface temperature T from the internal temperature sensor 11. Is done.

  When the control circuit 16 detects that the temperature information is output from the demodulation circuit 26 of the R / W unit 21 in step S4, the dedicated cooking utensil 3 having a wireless communication function is set on the heating mark of the top plate 2. Recognize that it is, and perform a dedicated automatic kettle cooking. FIG. 9 shows the contents of dedicated automatic water cooking. The control circuit 16 periodically sends temperature information from the tag unit 30 through the demodulation circuit 26 of the R / W unit 21 while heating the cooking utensil 3 with a constant heating power of 3 kW. The timing at which the thermal power is lowered to the heat insulation value is detected based on the temperature information from the tag unit 30. Hereinafter, the contents of the dedicated automatic water heating cooking will be described.

When the control circuit 16 detects that the temperature information is output from the demodulation circuit 26 in step S4 in FIG. 7, the dedicated cooking utensil is obtained based on acquiring the output signal from the internal temperature sensor 11 in a wired manner in step S15. 3 indirect surface temperature T is detected and stored in RAM in chronological order.
When the control circuit 16 proceeds to step S16, the control circuit 16 oscillates a data request signal from the antenna coil 27 of the R / W unit 21. The data request signal is oscillated every set time (every 1 sec). When the control circuit 16 oscillates the data request signal in step S16, the control circuit 16 passes through the demodulator circuit 26 of the R / W unit 21 in step S17. It is determined whether or not there is a response to temperature information. When it is detected that there is temperature information, the process proceeds to step S18.

  When the control circuit 16 proceeds to step S18, it determines whether the temperature information is the hot water completion data or the hot water continuation data. Here, when it is detected that the temperature information is the completion data of the water heating, it is recognized that the cooking utensil 3 has reached the water heating recognition temperature Tb, and the process proceeds to the heat retaining process in step S14. Here, the thermal power is lowered from 3 kW to the heat insulation value at once, and the thermal power is adjusted in the vicinity of the heat insulation value so that the indirect surface temperature T of the cooking utensil is heated and maintained at the recognition temperature Tb. That is, when the temperature information from the R / W unit 21 exists at the beginning of cooking, it is determined that the dedicated cooking utensil 3 is used, and the progress of cooking is controlled based on the temperature information from the tag unit 30.

  When the control circuit 16 detects that no temperature information is detected via the demodulation circuit 26 of the R / W unit 21 in step S17, it determines that an abnormality has occurred in the R / W unit 21 or the tag unit 30, and proceeds to step S19. Transition. Here, the earliest stored data of the indirect surface temperature T is detected from the RAM and compared with the determination value T1. For example, when “T ≦ T1” is detected, the process proceeds from step S19 to S5, and general-purpose automatic water heating cooking is performed while detecting the indirect surface temperature T of the cooking utensil 3 based on the temperature signal from the internal temperature sensor 11. To do.

  When the control circuit 16 detects “T> T1” in step S19, the control circuit 16 proceeds to step S20 and compares the earliest stored data of the indirect surface temperature T with the determination value T2. For example, when “T ≦ T2” is detected, the process proceeds from step S20 to S7, and the heating power is reduced from 3 kW to 2 kW. When “T> T2” is detected, the process proceeds from step S20 to S10, and the heating power is reduced from 3 kW to 1 kW. Then, general-purpose automatic hot water cooking is executed while detecting the indirect surface temperature T of the cooking utensil 3 based on the temperature signal from the internal temperature sensor 11. That is, when the temperature information from the R / W unit 21 disappears during cooking, an abnormality in the R / W unit 21 or the tag unit 30 is determined. Then, the heating power is lowered to a value corresponding to the current heating state, and the subsequent cooking is controlled based on the temperature signal from the internal temperature sensor 11.

  According to the first embodiment, the external temperature sensor 29 is fixed to the cooking utensil 3 not affected by the magnetic field from the IH coil 10 and the top plate 2 is not interposed, and the temperature corresponding to the detection result of the external temperature sensor 29 is obtained. Since the cooking content is controlled based on wirelessly communicating information, the actual temperature of the cooking utensil 3 can be detected with high accuracy without performing step-down control of the heating power. For this reason, since the cooking utensil 3 can be continuously heated with high heating power, it becomes possible to finish the cooked product in a desired state in a short time.

Since power is supplied wirelessly from the R / W unit 21 to the tag unit 30, it is not necessary to mount a power source on the cooking utensil 3. This eliminates the need to replace and charge the power source, improving usability.
The tag unit 30 transmits temperature information based on amplitude modulation of the power carrier signal from the R / W unit 21. For this reason, it is not necessary to mount an oscillation circuit for a carrier signal in the tag unit 30, and hence the size of the tag unit 30 can be suppressed.

Based on the fact that the data request signal is oscillated from the R / W unit 21 to the tag unit 30, the transmission of temperature information is wirelessly called. For this reason, since the amplitude modulation of the carrier signal only needs to be performed when responding to the interrogation from the R / W unit 21, power consumption can be reduced.
In the first embodiment, when the automatic cooking is performed using the dedicated cooking utensil 3, the heat retaining process is performed based on the temperature signal from the internal temperature sensor 11, but is not limited thereto. For example, the heat retaining process may be performed based on temperature information from the tag unit 30.

  As shown in FIG. 11, the control circuit 16 is connected with an R / W unit 50 corresponding to receiving means, transmitting / receiving means, and first transmitting / receiving means. The R / W unit 50 includes an oscillation circuit 51, a transmission dedicated resonance circuit 52, an antenna drive circuit 53, a reception dedicated resonance circuit 54, and a demodulation circuit 55. The oscillation circuit 51 receives energy from a DC power source. It is converted into an oscillation signal having a constant frequency of 125 kHz.

  The resonance circuit 52 includes a transmission-dedicated antenna coil 56 and a resonance capacitor 57. The antenna drive circuit 53 drives the antenna coil 56 with current based on the oscillation signal from the oscillation circuit 51, and converts the antenna coil 56 into a transmission signal. A corresponding carrier signal is transmitted. FIG. 12A shows a current waveform of a carrier signal oscillated from the antenna coil 56, and the carrier signal is used as a power dedicated signal having a constant amplitude. The antenna coil 56 corresponds to a power transmission antenna.

  As shown in FIG. 11, the resonance circuit 54 is composed of a reception-only antenna coil 58 and a resonance capacitor 59. The demodulation circuit 55 shapes the current flowing through the antenna coil 58 and applies it to the control circuit 16 for control. The circuit 16 recognizes the content received by the antenna coil 58 based on the detection signal from the demodulation circuit 55. The antenna coil 58 corresponds to an information receiving antenna.

  A tag unit 60 corresponding to a transmission unit, a transmission / reception unit, and a second transmission / reception unit is mechanically fixed to the cooking appliance 3, and the tag unit 60 is electrically connected to the external temperature sensor 29 via a lead wire. ing. The tag unit 60 detects a temperature signal from the external temperature sensor 29 based on the wireless supply of power from the R / W unit 50, and the R / W unit 50 detects temperature information corresponding to the detection result of the temperature signal. Is transmitted wirelessly, and is configured as follows.

  The resonance circuit 61 is composed of a reception-only antenna coil 62 and a resonance capacitor 63, and the antenna coil 62 of the resonance circuit 61 is R / W based on placing the cooking utensil 3 on the heating mark of the top plate 2. A carrier signal oscillated from the antenna coil 56 is magnetically coupled to the antenna coil 56 dedicated to transmission of the unit 50. The rectifier circuit 64 rectifies the carrier signal from the resonance circuit 61, and the power supply circuit 65 has a 5V for the tag unit 60 based on the rectified output from the rectifier circuit 64, as shown in FIG. Drive power supply Vdd is generated. The antenna coil 62 corresponds to a power receiving antenna.

  As shown in FIG. 11, the temperature detection circuit 66 outputs a voltage signal of a level corresponding to the resistance change of the external temperature sensor 29, and the control circuit 67 outputs the voltage signal from the temperature detection circuit 66 as A / D. Based on the conversion, the direct surface temperature To of the cooking utensil 3 is detected. FIG. 14 shows the relationship between the detected temperature of the external temperature sensor 29 and the input voltage of the control circuit 67. When the detected temperature of the external temperature sensor 29 is 250 ° C. or lower, the input voltage of the control circuit 67 is the external temperature sensor. It increases in proportion to the detected temperature of 29. The control circuit 67 is mainly composed of a microcomputer, and has a CPU, a ROM, a RAM, and an I / O.

  As shown in FIG. 11, the oscillation circuit 68 converts the energy from the DC power source into an oscillation signal with a constant frequency of 8 MHz. The clock frequency 31.25 kHz of the control circuit 67 is the oscillation of 8 MHz from the oscillation circuit 68. It is generated by dividing the signal. As shown in FIG. 13A, the drive pulse generation circuit 69 generates an 8 MHz pulse signal based on the oscillation signal from the oscillation circuit 68, and the modulation circuit 70, as shown in FIG. The pulse signal from the drive pulse generation circuit 69 is amplitude-modulated. The modulation circuit 70 is ON / OFF controlled by a control circuit 67. The control circuit 67 detects a voltage signal from the temperature detection circuit 66 at every set time (specifically every 1 sec), and the modulation circuit 70 The pulse signal is modulated by controlling the driving at every set time (specifically every 1 sec) based on the detection result of the signal, and the temperature value data corresponding to the temperature information is set every specific time (specifically every 1 sec). To generate.

  FIG. 13B shows a drive signal output from the control circuit 67 to the modulation circuit 70. This drive signal has start data DS for generating the start bit SB, temperature data DO for generating the data bit DB, and end data DE for generating the end bit EB, and the modulation period of the pulse signal is 64 μsec (31. 25 kHz). The temperature data DO of the drive signal is generated by the CPU of the control circuit 67 based on the voltage signal from the temperature detection circuit 66. As shown in FIG. 14, for example, the input voltage of the control circuit 67 is "4.1V. ”Is recognized as a temperature value, and temperature data DO of“ 11010010 ”is generated.

  As shown in FIG. 11, the resonance circuit 71 includes an antenna coil 72 dedicated to transmission and a resonance capacitor 73, and the antenna coil 72 of the resonance circuit 71 places the cooking utensil 3 on the heating mark of the top plate 2. Based on this, it is magnetically coupled to the antenna coil 58 dedicated to reception of the R / W unit 50. The antenna drive circuit 74 drives the antenna coil 72 with current based on a pulse signal that turns on and off the modulation circuit 70, and oscillates a carrier signal from the antenna coil 72. The demodulation circuit 55 of the R / W unit 50 includes an antenna coil 58. The waveform of the current flowing through the signal is applied to the control circuit 16, and the control circuit 16 detects the temperature value data from the tag unit 60 based on the detection signal from the demodulation circuit 55.

  FIG. 13C shows the current waveform flowing through the antenna coil 58, and the control circuit 16 recognizes the start bit SB, data bit DB, and end bit EB based on the detection signal from the demodulation circuit 55. FIG. That is, the tag unit 60 periodically transmits temperature information without being requested from the R / W unit 50, and the tag unit 60 transmits the temperature information by using the dedicated carrier for power from the R / W unit 50. It starts automatically based on receiving and activating the signal wirelessly. The antenna coil 72 corresponds to an information transmission antenna.

An operation control program is recorded in the ROM of the control circuit 16, and the CPU of the control circuit 16 performs cooking by controlling the drive of the IH coil 10 based on the operation control program. Hereinafter, the control contents of the control circuit 16 when the automatic water heater key 6 is operated will be described.
When the control circuit 16 detects that the automatic water heater key 6 has been operated, the automatic water heater cooking is started with the heating power of 3 kW in step S1 of FIG. 15, and the power transmission to the R / W unit 50 is started in step S2. Then, based on the activation of the R / W unit 50, a carrier signal dedicated for power is oscillated from the antenna coil 56 dedicated for transmission.

  When the control circuit 16 proceeds to step S4, the control circuit 16 determines the presence or absence of temperature information via the demodulation circuit 55 of the R / W unit 50. For example, when a general-purpose cooking utensil having no wireless communication function is set on the heating mark of the top plate 2, temperature information is not output from the demodulation circuit 55. In this case, the control circuit 16 recognizes that a general-purpose cooking utensil is used, and performs general-purpose automatic kettle cooking. As described in [Embodiment 1], this automatic hot water cooking is to gradually reduce the heating power to 3 kW · 2 kW · 1 kW based on the output signal from the internal temperature sensor 11, and the surface temperature T of the cooking utensil When the rate of change ΔT over time becomes smaller than the determination value ΔTb, it is determined that the cooking utensil has reached the recognition temperature Tb, and the heat retaining process is performed.

  When the dedicated cooking utensil 3 having a wireless communication function is set on the heating mark of the top plate 2, the antenna coil 62 dedicated to reception of the tag unit 60 receives a carrier signal dedicated to power from the R / W unit 50. Based on this, the drive power supply of the tag unit 60 is generated, and the control circuit 67 of the tag unit 60 is activated. The temperature information is periodically oscillated from the antenna coil 72 dedicated to transmission of the tag unit 60, and the control circuit 16 of the R / W unit 50 periodically detects the temperature information via the demodulation circuit 55. The direct surface temperature To of the cooking utensil 3 is periodically acquired. In this case, the control circuit 16 recognizes that the dedicated cooking utensil 3 is set on the heating mark of the top plate 2 and executes dedicated automatic water heating cooking.

  FIG. 16 shows the contents of the dedicated automatic kettle cooking, and the control circuit 16 periodically detects temperature information from the tag unit 60 while heating the cooking utensil 3 with a constant heating power of 3 kW, and sets the heating power to a heat insulation value. The drop timing is detected based on temperature information. Hereinafter, the contents of the dedicated automatic water heating cooking will be described. When the control circuit 16 detects that the temperature information from the tag unit 60 exists in step S4 of FIG. 15, the control circuit 16 acquires the output signal from the internal temperature sensor 11 in a wired manner in step S15. The indirect surface temperature T is detected and stored in the RAM in chronological order.

  When the control circuit 16 proceeds to step S17, the control circuit 16 determines whether or not temperature information is output from the demodulation circuit 55 of the R / W unit 50. For example, when it is detected that temperature information is output, a direct surface temperature To is detected based on the temperature information in step S21, and in step S22, a time is calculated from the difference between the current surface temperature To and the previous surface temperature To. A typical temperature change rate ΔTo is calculated.

  In step S23, the control circuit 16 compares the calculation result of the temperature change rate ΔTo with the determination value ΔTb. Here, when “ΔTo <ΔTb” is detected, it is determined that the cooking utensil 3 has reached the recognition temperature Tb by boiling water, and the process proceeds to the heat retaining process in step S24. Here, the thermal power is lowered from 3 kW to the thermal insulation value at once, and the thermal power is adjusted in the vicinity of the thermal insulation value so that the surface temperature To based on the temperature information from the tag unit 60 is heated and maintained at the recognition temperature Tb.

  When the control circuit 16 detects that no temperature information is detected from the demodulation circuit 55 of the R / W unit 50 in step S17, it determines that an abnormality has occurred in the R / W unit 50 or the tag unit 60. Then, the first stored data of the indirect surface temperature T is detected from the RAM and compared with the determination values T1 and T2. For example, if “T ≦ T1” is detected in step S19, the process proceeds to step S5. If “T ≦ T2” is detected in step S20, the process proceeds to step S7. If “T> T2” is detected in step S20, the process proceeds to step S5. It transfers to S10 and performs general-purpose automatic kettle cooking, detecting the indirect surface temperature T of the cooking appliance 3. FIG.

According to the second embodiment, the absolute temperature value data of the cooking utensil 3 is transmitted from the tag unit 60 to the R / W unit 50 as temperature information. For this reason, since the use range of temperature information spreads compared with the case where relative values such as high and low are transmitted as temperature information, various types of cooking can be performed based on wireless information.
The tag unit 60 is configured to oscillate, as temperature information, an 8 MHz carrier signal synchronized with the operating frequency 31.25 kHz of the control circuit 67. For this reason, since the operating frequency of 31.25 kHz of the control circuit 67 can be generated by dividing the 8 MHz carrier signal for temperature information, the operating frequency oscillation circuit becomes unnecessary.

  Since two types of signals, ie, a power dedicated signal and a temperature information dedicated signal, are used as carrier signals, there is no need to transmit temperature information based on amplitude modulation of the power carrier signal. For this reason, the use efficiency of the carrier signal for power increases, and it becomes possible to stably generate a large drive power supply Vdd, which is advantageous in terms of power supply when a microcomputer is used as the tag unit 60.

A carrier signal for power and a carrier signal for temperature information having different frequencies were used. Specifically, a long wave in the kH band is always oscillated as a carrier signal for power, and a short wave in the MHz band is oscillated only when necessary as a carrier signal for temperature information, so that the regulations of the Radio Law can be easily cleared. it can.
In the second embodiment, the heat treatment is performed based on the temperature information from the tag unit 60 in the case of performing automatic boiling using the dedicated cooking utensil 3, but the present invention is not limited to this. The heat retaining process may be performed based on the temperature signal from the internal temperature sensor 11.

  In the first to second embodiments, the presence / absence of water boiling is determined based on the temperature information from the tag unit 30 and the temperature information from the tag unit 60. In addition, the presence / absence of water is determined. You may do it. In this case, based on the temperature information from the tag unit 30 and the temperature information from the tag unit 60, when boiling of water is confirmed within the determination time or less, it is determined that the water is not present, and automatic boiling cooking is performed. It is preferable to stop.

In the said 1st-2nd Example, although the temperature information from the tag part 30 and the temperature information from the tag part 60 were utilized for automatic kettle cooking, it is not limited to this, Tempura cooking, hot water cooking, It can utilize for the automatic cooking performed by heating the cooking utensil 3 to preset temperature, such as fried food cooking.
In the said 1st-2nd Example, although it was set as the structure which supplies electric power to the tag part 30 and the tag part 60 from the R / W part 21 and the R / W part 50, it is not limited to this. For example, it is good also as a structure which mounts power supplies, such as a primary battery and a secondary battery, in the tag part 30 and the tag part 60. FIG.

The figure which shows 1st Example of this invention (The figure which shows the state which set the special cooking utensil to the top plate) Block diagram showing electrical configuration of R / W unit and tag unit Block diagram showing electrical configuration of inverter circuit unit and inverter control unit (A) is a figure which shows the current waveform which flows into the antenna coil of R / W part, (b) is a figure which shows the voltage waveform output from the rectifier circuit of a tag part, (c) is output from the power supply circuit of a tag part. Figure showing the voltage waveform (A) is a diagram showing data stored in the memory of the tag unit, (b) is a diagram showing a voltage waveform output from the modulation circuit of the tag unit to the load changing circuit, and (c) is an antenna coil of the R / W unit. Diagram showing the current waveform The figure which shows the current waveform which flows into the antenna coil of R / W part Flow chart showing control contents of control circuit Perspective view showing appearance of cooking heater The figure which shows the cooking content at the time of using the dedicated cooking appliance which has a wireless communication function The figure which shows the cooking content at the time of using the general purpose cooking appliance which does not have a wireless communication function FIG. 2 equivalent diagram showing a second embodiment of the present invention. (A) is a figure which shows the current waveform which flows into the antenna coil only for transmission of R / W part, (b) is a figure which shows the voltage waveform output from the power supply circuit of a tag part. (A) is a voltage waveform diagram showing a pulse signal generated by the drive pulse generation circuit of the tag unit, (b) is a diagram showing a voltage waveform output from the control circuit of the tag unit to the modulation circuit, and (c) is an R / R The figure which shows the current waveform which flows into the antenna coil only for reception of W section The figure which shows the relationship between the detection temperature of the external temperature sensor and the input voltage of the control circuit Flow chart showing control contents of control circuit The figure which shows the cooking content at the time of using the dedicated cooking appliance which has a wireless communication function 1 equivalent diagram showing a conventional example

Explanation of symbols

2 is a top plate (supporting means), 3 is a cooking utensil, 10 is an IH coil (heating means), 16 is a control circuit (control means), 21 is an R / W unit (receiving means, transmitting / receiving means), 29 is an external temperature Sensor (temperature detection means), 30 is a tag part (transmission means), 50 is an R / W part (reception means, transmission / reception means, first transmission / reception means), 56 is an antenna coil (power transmission antenna), and 58 is an antenna. A coil (information receiving antenna), 60 is a tag part (transmitting means, second transmitting / receiving means), 62 is an antenna coil (power receiving antenna), and 72 is an antenna coil (information transmitting antenna).

Claims (8)

A support means for supporting the cooking utensil having a temperature detection means and a transmission means for wirelessly transmitting temperature information according to the detection result of the temperature detection means;
Heating means for heating the cooking utensil;
Receiving means for wirelessly receiving temperature information transmitted from the transmitting means of the cooking utensil;
A heating cooker comprising: control means for drivingly controlling the heating means based on a reception result of the receiving means.   The cooking device according to claim 1, wherein the receiving unit wirelessly supplies power to the transmitting unit.   The cooking device according to claim 2, wherein the transmission means transmits temperature information based on amplitude modulation of a power carrier signal oscillated from the reception means.   The cooking device according to any one of claims 1 to 3, wherein the transmission unit transmits a temperature value of the cooking utensil as temperature information.   The cooking device according to any one of claims 1 to 4, wherein the receiving unit includes a transmission / reception unit that wirelessly requests the transmission unit to transmit temperature information.   The cooking device according to any one of claims 1 to 5, wherein the transmission means oscillates a carrier signal synchronized with an internal operating frequency as temperature information. The receiving means comprises first transmitting / receiving means having a power transmitting antenna for oscillating a carrier signal for power and an information receiving antenna for receiving a carrier signal for temperature information,
7. The transmitting means comprises a second transmitting / receiving means having a power receiving antenna for receiving a carrier signal for power and an information transmitting antenna for transmitting a carrier signal for temperature information. The cooking device according to any one of the above. 8. The cooking device according to claim 7, wherein the receiving means and the transmitting means oscillate signals having different frequencies as a carrier signal for power and a carrier signal for temperature information.

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