Cooking appliance, control method, and computer program

Abstract

To efficiently thaw frozen food items that need to be heated. [Solution] The heating cooker according to the present disclosure comprises an inner box for containing an object to be heated, a temperature sensor for detecting the temperature inside the inner box, a magnetron for irradiating microwaves when energized, a heater for generating heat when energized, and a control unit for controlling the energization of the magnetron and the heater. The control unit determines the energization time of the heater based on the temperature detected by the temperature sensor, and after energizing the heater, energizes the magnetron.

Description

Technical Field

[0001] The present technology relates to a heating cooker, a control method, and a computer program. Background Art

[0002] Conventionally, heating cookers provided with a magnetron and a heater have been proposed. For example, the heating cooker described in Patent Document 1 includes a DC power supply circuit including a full-wave rectifier circuit connected to an AC power supply, a heater and a semiconductor switching element connected in series to the DC power supply circuit, input current detection means for detecting an input current from the AC power supply, and input control means for controlling the switching element such that a detected current value of the input current detection means is less than an upper limit value, wherein an inverter circuit that includes a resonance circuit and a high-frequency switching element and drives a microwave generator is connected to the DC power supply circuit. Prior Art Documents Patent Documents

[0003] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2001-023770 Summary of the Invention Problems to be Solved by the Invention

[0004] However, the heating cooker described in Patent Document 1 does not take into consideration efficiently thawing a frozen object to be heated.

[0005] The present disclosure has been made in view of such circumstances, and an object thereof is to efficiently thaw a frozen object to be heated. Means for Solving the Problems

[0006] The heating appliance according to this disclosure comprises an inner box for containing an object to be heated, a temperature sensor for detecting the temperature inside the inner box, a magnetron for irradiating microwaves when energized, a heater for generating heat when energized, and a control unit for controlling the energization of the magnetron and the heater. The control unit determines the energization time of the heater based on the temperature detected by the temperature sensor, and after energizing the heater, energizes the magnetron.

[0007] In this disclosure, the heating appliance operates a heater for a time corresponding to the temperature inside the inner box containing the object to be heated (internal temperature), and after heating by raising the temperature, the object to be heated is heated by microwaves emitted by a magnetron. Since microwaves heat the object by vibrating the liquid free water contained in the object to be heated, the object will not be heated if microwaves are irradiated onto the object to be heated while the contained free water is frozen (solid). First, by driving the heater, the temperature inside the inner box and the object to be heated is raised, causing some of the free water contained in the object to melt. Then, by energizing the magnetron, microwaves vibrate the melted free water in the object to be heated, heating the object and proceeding with thawing. In this way, by driving the heater, the object to be heated contains liquid free water, making it more reactive to microwaves, so the object to be heated is thawed efficiently. Furthermore, by determining the time the heater is energized (driving time) according to the internal temperature before heating begins, it is possible to thaw more efficiently.

[0008] In the heating appliance according to this disclosure, the control unit determines that the power supply time for the heater will be longer as the temperature inside the inner box decreases.

[0009] In this disclosure, the control unit of the heating appliance increases the heater's energizing time (driving time) when the internal temperature before heating is lower, and decreases the heater's energizing time (driving time) when the internal temperature before heating is higher. This makes it possible to reduce variations in the liquid free water content of the object to be heated before microwave irradiation.

[0010] The heating appliance according to this disclosure has a control unit that receives input for the amount of food to be heated contained in the inner box, and determines the energizing time of the magnetron according to the input amount.

[0011] In this disclosure, it is possible to prevent underheating or overheating by determining the energizing time of the magnetron according to the amount of material to be heated.

[0012] The heating appliance according to this disclosure has a control unit that receives input for the selection of heating intensity and determines the output intensity of the magnetron according to the selected heating intensity.

[0013] In this disclosure, the user of the cooking appliance selects a heating intensity, and the magnetron is driven with an output intensity corresponding to the selected heating intensity, thereby enabling a degree of thawing based on the user's experience or preference.

[0014] In the heating cooker according to this disclosure, the control unit causes the magnetron to output at a first output intensity, and then causes it to output at a second output intensity that is weaker than the first output intensity.

[0015] In this disclosure, by initially driving the magnetron with a strong first power intensity, the solid free water on the surface of the object to be heated can be efficiently melted. Subsequently, by switching to a weaker second power intensity, microwaves can be irradiated onto the liquid free water surrounding the solid free water, preventing overheating of the thawed portion of the object to be heated, thereby promoting the melting of the solid free water.

[0016] The heating cooker according to this disclosure has a control unit that receives input of the amount of food to be heated contained in the inner box, and determines that the energizing time of the magnetron at the first output intensity is longer the larger the input amount, and determines that the energizing time of the magnetron at the second output intensity is shorter.

[0017] In this disclosure, the smaller the amount (weight) of the object to be heated, the higher the ratio of the surface area to the amount of the object to be heated. When an object with a high ratio of surface area to amount is irradiated with microwaves at a high power intensity for a long time, the proportion of heating to the surface increases, and there is a risk of overheating of the surface of the object to be heated. The smaller the amount of the object to be heated, the shorter the energizing time of the magnetron at the strong first power intensity and the longer the energizing time of the magnetron at the weak second power intensity can prevent overheating of the object to be heated.

[0018] The heating cooker according to this disclosure has a control unit that receives input for the selection of a defrosting mode. If a first defrosting mode is selected, the control unit causes the magnetron to output at a first output intensity, and then at a second output intensity weaker than the first output intensity. If a second defrosting mode is selected, the control unit causes the magnetron to output at a constant output intensity.

[0019] In this disclosure, the defrosting mode is selected from, for example, a full defrosting mode (first defrosting mode) and a partial defrosting mode (second defrosting mode). When the full defrosting mode is selected, the magnetron is first powered at a first power intensity, and then powered at a second power intensity weaker than the first power intensity, thereby enabling defrosting to the center of the heated object.

[0020] The control method according to this disclosure is a control method for a cooking appliance comprising an inner box for containing an object to be heated, a temperature sensor for detecting the temperature inside the inner box, a magnetron for irradiating microwaves by energizing, a heater that generates heat by energizing, and a control unit for controlling the energizing of the magnetron and the heater, wherein the control unit determines the energizing time of the heater based on the temperature detected by the temperature sensor, and after energizing the heater, energizes the magnetron.

[0021] In the present disclosure, driving the heater causes the object to be heated to contain free liquid water, making it more susceptible to reacting with microwaves, so that the object to be heated is efficiently thawed. Further, by determining the energization time (driving time) of the heater according to the internal chamber temperature before the start of heating, more efficient thawing can be achieved.

[0022] A computer program according to the present disclosure is a computer program executable by a heating cooker that includes an inner box for accommodating an object to be heated, a temperature sensor for detecting the temperature inside the inner box, a magnetron that irradiates microwaves when energized, a heater that generates heat when energized, and a control unit that controls energization to the magnetron and the heater. The computer program causes the control unit to execute a process of determining the energization time of the heater based on the temperature detected by the temperature sensor, energizing the heater, and then energizing the magnetron.

[0023] In the present disclosure, driving the heater causes the object to be heated to contain free liquid water, making it more susceptible to reacting with microwaves, so that the object to be heated is efficiently thawed. Further, by determining the energization time (driving time) of the heater according to the internal chamber temperature before the start of heating, more efficient thawing can be achieved. [Effects of the Invention]

[0024] In the heating cooker according to one embodiment of the present disclosure, it is possible to efficiently thaw a frozen object to be heated. [Brief Description of the Drawings]

[0025] [Figure 1] It is a perspective view of the heating cooker. [Figure 2] It is a schematic right side cross-sectional view of the heating cooker. [Figure 3] It is a schematic front cross-sectional view of the heating cooker. [Figure 4] It is a circuit diagram and a block diagram showing the main configuration of the heating cooker. [Figure 5] It is a flowchart showing an example of processing of the control circuit. [Figure 6] This is an explanatory diagram showing an example of a display on a control panel. [Figure 7] This is an explanatory diagram showing an example of a heater energization time table. [Figure 8] This is an explanatory diagram showing an example of a magnetron output intensity table. [Figure 9] This is an explanatory diagram showing an example of a magnetron energizing time table. [Modes for carrying out the invention]

[0026] (Embodiment) Embodiments of this disclosure will be described below with reference to the drawings. In the following description, the arrows in the drawings will indicate the top / bottom, front / back, and left / right directions. For illustrative purposes, the dimensional ratios in the drawings may differ from the actual ratios, and parts may be exaggerated or omitted.

[0027] Figure 1 is a perspective view of the cooking appliance 1. In the figure, 1 is a cooking appliance, and cooking appliance 1 is configured as, for example, a microwave oven. Cooking appliance 1 includes an outer casing 11 and a door 12. Figure 2 is a schematic right-side cross-sectional view of the cooking appliance 1. As shown in Figures 1 and 2, the outer casing 11 is rectangular in shape and has an open front. The door 12 opens and closes the front opening of the outer casing 11. A handle 121, an operating section 122, and a start button 123 are provided on the outer surface of the door 12. As shown in Figure 2, the cooking appliance 1 includes an inner box 13 and a partition wall 14. The inner box 13 is housed in the outer box 11. The inner box 13 is rectangular in shape and has an open front. When the door 12 opens and closes the front opening of the outer box 11, the front opening of the inner box 13 is also opened and closed. The outer casing 11, door 12, and inner casing 13 are heat-resistant and microwave-reflective. For example, the outer casing 11 and inner casing 13 are made of metal.

[0028] Figure 3 is a schematic front cross-sectional view of the cooking appliance 1. As shown in Figures 2 and 3, a recess is provided in the center of the inner bottom surface of the inner box 13, and the opening of this recess is watertightly closed by a partition wall 14 positioned along the bottom plate of the inner box 13. The partition wall 14 has heat resistance and microwave permeability and is made of, for example, ceramic.

[0029] The area of ​​the inner box 13 above the partition wall 14 is used as the heating chamber 2. The inner top surface of the inner box 13 and the top surface of the partition wall 14 function as the inner top and bottom surfaces of the heating chamber 2. The portions of the left and right inner walls of the inner box 13 above the partition wall 14 function as the left and right inner walls of the heating chamber 2. The inner surface of the door 12 functions as the front inner wall surface of the heating chamber 2. The door 12 comprises, for example, a metal plate (perforated metal) with numerous through-holes and transparent heat-resistant glass covering this metal plate. When the door 12 is closed, the heating chamber 2 can be seen through the door 12.

[0030] The area below the partition wall 14 of the inner box 13 (the recess in the center of the inner bottom surface of the inner box 13) is used as the antenna room 10. The cooking appliance 1 is equipped with an irradiation device 15. The irradiation device 15 is equipped with a rotating antenna 151 and a magnetron 152. The rotating antenna 151 is housed in the antenna chamber 10. The rotating antenna 151 is disc-shaped with both sides facing up and down, and rotates circumferentially driven by a motor (not shown). The magnetron 152 is housed in a space enclosed, for example, by an outer casing 11 and an inner casing 13. The magnetron 152 generates microwaves. The wavelength of the microwaves generated by the magnetron 152 is approximately 12 cm.

[0031] The microwaves generated by the magnetron 152 are guided into the antenna chamber 10 by a waveguide member (not shown). The microwaves guided into the antenna chamber 10 are scattered by the rotating antenna 151. The scattered microwaves pass through the partition wall 14 and are irradiated from below into the internal space of the heating chamber 2. A cooking dish 3 is housed in the heating chamber 2. The cooking dish 3 is heat-resistant and microwave-reflective, and is made of, for example, metal. The cooking dish 3 generates heat when exposed to microwaves. Food 4 (the item to be heated) is placed on the cooking plate 3. The heat emitted by the cooking plate 3 when it receives microwaves cooks the food 4 placed on it. Note that the cooking plate 3 does not necessarily have to be placed inside the heating chamber 2, and the food 4 (the item to be heated) may be placed on the bottom surface of the heating chamber 2.

[0032] The cooking appliance 1 is equipped with a heater 17. The heater 17 comprises, for example, a cylindrical body and a carbonaceous heating element (graphite) housed within the cylindrical body that has two-dimensional isodirectional thermal conductivity in the planar direction. Instead of this heating element, a coiled electric heating wire such as nichrome wire or tungsten wire may be used. The heater 17 is installed on the lower side of the upper surface of the inner box 13 and on the upper side of the cooking plate 3, i.e., at the top of the heating chamber 2, and generates heat when power is supplied, radiating heat from above the food 4. The location where the heater 17 is installed is not limited to the top of the heating chamber 2, but may be installed, for example, on the side or bottom of the heating chamber 2. In addition, multiple heaters may be provided in the heating chamber 2.

[0033] Figure 4 is a circuit diagram and block diagram showing the main components of the heating appliance 1. In Figure 4, solid lines indicate power lines and dashed lines indicate signal lines. The heating appliance 1 comprises a magnetron 152, an inverter 153, a heater 17, a converter 18, a control circuit 19, a temperature sensor 19a, and an operation panel 19b.

[0034] The control circuit 19 is composed of, for example, a microcomputer and includes a control unit 191, a memory unit 192, and an input / output interface 193. The control unit 191 is composed of a CPU or logic circuit (e.g., FPGA). The control unit 191 performs various control and calculation processes by reading and executing a program P and data pre-stored in the memory unit 192. The control unit 191 may be configured to perform multiple processes in parallel using multiple CPUs (multi-CPU) or a multi-core CPU.

[0035] The memory unit 192 of the control circuit 19 is composed of volatile memory elements such as RAM (Random Access Memory) or non-volatile memory elements such as ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable ROM), or flash memory. The memory unit 192 stores a program P for performing various control and calculation processes, a heater energization time table T1, a magnetron output strength table T2, and a magnetron energization time table T3. Details of the heater energization time table T1, magnetron output strength table T2, and magnetron energization time table T3 will be described later.

[0036] The input / output interface 193 of the control circuit 19 is connected to the inverter 153, heater 17, temperature sensor 19a, and control panel 19b via signal lines, and transmits and receives signals with each connected component. Details of the information indicated by the signals transmitted and received with each component will be described later.

[0037] The temperature sensor 19a is located inside the inner box 13, for example near the magnetron 152, and detects the temperature inside the inner box 13 (internal temperature) and transmits it to the control circuit 19. The control panel 19b includes an operation unit 122 and a start button 123, and receives input from the user of the cooking appliance 1 regarding the amount of food to be heated (amount to be defrosted), heating intensity, and defrost mode selection, and transmits the input information to the control circuit 19.

[0038] The cooking appliance 1 is connected to a household power supply (AC power supply) S. The heater 17 is also connected to the household power supply S. In other words, the heater 17 is supplied with AC power supplied from the household power supply S.

[0039] The inverter 153 is connected to a household power supply S via a converter 18, and DC power is supplied to it. That is, the converter 18 and inverter 153 and the heater 17 are connected in parallel. The converter 18 receives AC power supplied from the household power supply S, converts the received AC power to DC power, and outputs it to the inverter 153. The inverter 153 converts the DC power supplied from the converter 18 to AC power and supplies it to the magnetron 152. At this time, the inverter 153 converts the voltage of the input power to a voltage corresponding to the output strength of the magnetron 152 received from the control circuit 19, and supplies the power of the converted voltage to the anode 152a of the magnetron 152. Note that the inverter 153 may be configured as an integral part of the magnetron 152, or it may be an internal component of the magnetron 152.

[0040] The control unit 191 of the control circuit 19 determines the energizing time of the heater 17 based on the internal temperature obtained from the temperature sensor 19a. The control unit 191 also determines the energizing time of the magnetron 152 based on the defrosting amount (amount of food to be defrosted) and defrosting mode input at the control panel 19b. Furthermore, the control unit 191 determines the output intensity of the magnetron 152 based on the heating intensity and selected defrosting mode input at the control panel 19b.

[0041] The control unit 191 of the control circuit 19 transmits a power supply signal to the inverter 153 to supply power to the magnetron 152, for example, for a determined energizing time. The inverter 153 supplies power to the magnetron 152 while it is receiving the power supply signal. The control unit 191 also transmits a power supply signal to a switch located inside or adjacent to the heater 17, for example, for a determined energizing time. The switch remains in the ON state while it is receiving the power supply signal, and power is supplied to the heater 17. Alternatively, the inverter 153 may be configured to supply power to the magnetron 152 while it is receiving power without receiving a power supply signal, or it may be connected in series with the heater 17 and supply power to the magnetron 152 while the heater 17's switch is ON.

[0042] Figure 5 is a flowchart showing an example of the processing of the control circuit 19. The control unit 191 of the control circuit 19 acquires the defrost amount, heating intensity, and defrost mode input from the control panel 19b (S1). Figure 6 is an explanatory diagram showing an example of the display on the control panel 19b. The control panel 19b has a display for accepting input of the defrost amount, heating intensity, and defrost mode. The control panel 19b displays input fields for the defrost amount, heating intensity, and defrost mode.

[0043] The control panel 19b accepts input for the defrosting amount (the weight of the food to be heated placed inside the inner box 13) in the defrosting amount input field. The defrosting amount input field selectively displays weights in 50g increments, for example, from 100g to 500g. The weight displayed in the defrosting amount input field increases by 50g when the control unit 122 (see Figure 1) is rotated clockwise, and decreases by 50g when it is rotated counterclockwise. When the defrosting start button, described later, is selected, the weight displayed in the defrosting amount input field is sent to the control unit 191 as the defrosting amount. In addition, the type of food to be defrosted (meat, fish, rice, or beverage, etc.) may be selected and entered in the defrosting amount input field. Furthermore, the unit of the defrosting amount entered (g, number of pieces, number of cups, or mL, etc.) may be changed depending on the type of food to be heated.

[0044] The control panel 19b accepts input for heating intensity in the heating intensity input field. The heating intensity input field displays, for example, a five-level gauge. When the control unit 122 (see Figure 1) is rotated clockwise, the number of illuminated gauges increases by one, and when rotated counterclockwise, the number of illuminated gauges decreases by one. In the example shown in Figure 6, illuminated gauges are shown in black, and unilluminated gauges are shown in white. The heating intensity level (levels 1 to 5) is indicated by the number of illuminated gauges. When the start button 123, described later, is pressed, the level displayed in the heating intensity input field is transmitted to the control unit 191 as the heating intensity.

[0045] The control panel 19b accepts input for the decompression mode in the decompression mode input field. In the example shown in Figure 6, two modes, "Full Decompression" and "Partial Decompression," are displayed for selection. Full decompression mode corresponds to the first decompression mode, and partial decompression mode corresponds to the second decompression mode. A cursor is placed next to one of the modes displayed in the decompression mode input field. The decompression mode to which the cursor is placed changes, for example, when the control unit 122 (see Figure 1) is rotated. The mode to which the cursor is placed when the start button 123, described later, is pressed is transmitted to the control unit 191 as the decompression mode.

[0046] The control panel 19b includes a start button 123 to start powering on the heater 17 and the magnetron 152. When the start button 123 is pressed, the control panel 19b transmits to the control unit 191 the defrost amount displayed in the defrost amount input field, the heating intensity displayed in the heating intensity input field, and the defrost mode selected (indicated by the cursor) in the defrost mode input field.

[0047] The control unit 191 obtains the internal temperature of the inner box 13 from the temperature sensor 19a (S2). Based on the internal temperature, the control unit 191 determines the energizing time of the heater 17 (S3). Figure 7 is an explanatory diagram showing an example of the heater energizing time table T1. The heater energizing time table T1 stores the energizing time of the heater 17 for each internal temperature. The management items (fields) of the heater energizing time table T1 include an internal temperature field and an energizing time field. The internal temperature field stores the range of the internal temperature. In the example shown in Figure 7, the upper limit of each range is shown to include an equal value, but the lower limit may also include an equal value. The energizing time field stores the energizing time of the heater 17 for each internal temperature. In S3, the control unit 191 determines the energizing time of the heater 17 by reading the energizing time corresponding to the range of the internal temperature obtained from the temperature sensor 19a. The control unit 191 may determine the energizing time of the heater 17 by performing a predetermined calculation, such as multiplying the internal temperature (Celsius temperature, Fahrenheit temperature, or absolute temperature) by a predetermined coefficient.

[0048] The control unit 191 starts transmitting a power supply signal to the heater 17 (S4). After the power supply time calculated in S3 has elapsed since the start of transmitting the power supply signal to the heater 17, the control unit 191 stops transmitting the power supply signal to the heater 17 (S5).

[0049] The control unit 191 determines the output intensity of the magnetron 152 based on the heating intensity and defrosting mode obtained from the control panel 19b (S6). Figure 8 is an explanatory diagram showing an example of the magnetron output intensity table T2. The magnetron output intensity table T2 stores the output intensity of the magnetron 152 according to the selected heating intensity and defrosting mode. When the selected defrosting mode is the full defrosting mode (first defrosting mode), the control unit 191 causes the magnetron 152 to output at a first output intensity, and then at a second output intensity that is weaker than the first output intensity. In other words, in the full defrosting mode, the magnetron 152 performs two steps of output. In contrast, when the selected defrosting mode is the partial defrosting mode (second defrosting mode), the control unit 191 causes the magnetron 152 to output at a constant output intensity. In other words, in the partial defrosting mode, the magnetron 152 performs one step of output.

[0050] The management items (fields) of the magnetron output intensity table T2 include a heating intensity field, a full defrosting first step field, a full defrosting second step field, and a partial defrosting field. The heating intensity field stores the heating intensity level (levels 1 to 5) selected by the user. The full defrosting first step field stores the first output intensity (amount of energy supplied per unit time) when the full defrosting mode is selected. The full defrosting second step field stores the second output intensity when the full defrosting mode is selected. The partial defrosting field stores the output intensity when partial defrosting is selected. The control unit 191 determines the output intensity of the magnetron 152 by determining the record of the magnetron output intensity table T2 to refer to based on the selected heating intensity and by determining the field to refer to based on the selected defrosting mode. When the full defrosting mode is selected, the control unit 191 refers to the full defrosting first step field and the full defrosting second step field to determine the first and second output intensities. Here, output strength may refer to an equivalent amount of output that changes depending on the proportion of time the magnetron 152 is outputting power (energized time during the period) within a predetermined time period (e.g., 29 seconds). In this case, the power consumption of the magnetron 152 per unit time is constant while it is energized. For example, if the length of one period is 29 seconds, and the determined output strength is 100W, and the power consumption of the magnetron 152 is 250W, then the energized time during the period is set to {29·(100 / 250)} seconds per period. This results in an output strength of 100W equivalent to that of the magnetron 152. Note that the output strength may also be changed by changing the power consumption of the magnetron 152 per unit time (output voltage of the inverter 153).

[0051] As shown in Figure 8, when the full defrost mode is selected, the second power intensity is weaker than the first power intensity, regardless of the selected heating intensity. By irradiating the object to be heated with microwaves at a strong first power intensity, and then irradiating it with microwaves at a weak second power intensity, it is possible to prevent the surface of the object from overheating.

[0052] The control unit 191 determines the energizing time of the magnetron 152 based on the defrosting amount and defrosting mode obtained from the control panel 19b (S7). Figure 9 is an explanatory diagram showing an example of the magnetron energizing time table T3. The magnetron energizing time table T3 stores the energizing time of the magnetron 152 according to the defrosting amount and defrosting mode.

[0053] The management items (fields) in the magnetron energizing time table T3 include a defrosting amount field, a full defrosting first step field, a full defrosting second step field, and a partial defrosting field. The defrosting amount field stores the defrosting amount (weight of the object to be heated) entered by the user. The full defrosting first step field stores the energizing time of the magnetron 152 at the first output intensity when the full defrosting mode is selected. The full defrosting second step field stores the energizing time of the magnetron 152 at the second output intensity when the full defrosting mode is selected. The partial defrosting field stores the energizing time of the magnetron 152 when the partial defrosting mode is selected. The control unit 191 determines the energizing time to the magnetron 152 by determining the record in the magnetron energizing time table T3 to refer to based on the entered defrosting amount and determining the field to refer to based on the selected defrosting mode. If the full decompression mode is selected, the control unit 191 refers to the first full decompression step field and the second full decompression step field and determines the energizing time based on the first output intensity (first energizing time) and the energizing time based on the second output intensity (second energizing time).

[0054] As shown in Figure 9, the greater the amount to be defrosted (the weight of the object to be heated), the longer the energizing time of the magnetron 152 at the first power intensity, and the shorter the energizing time of the magnetron 152 at the second power intensity. The smaller the weight of the object to be heated, the higher the ratio of surface area to weight. If an object with a high ratio of surface area to weight is irradiated with microwaves at a high power intensity for a long time, the proportion of heating to the surface increases, and there is a risk of overheating of the surface of the object. By shortening the energizing time of the magnetron 152 at the strong first power intensity and lengthening the energizing time of the magnetron 152 at the weak second power intensity, it is possible to defrost the object while preventing overheating, as the weight of the object to be heated decreases.

[0055] Furthermore, the determination of the output intensity in S6 and the determination of the energizing time to the magnetron 152 in S7 may be performed before the start of transmitting the energizing signal to the heater 17 in S4, or between the start of transmitting the energizing signal to the heater 17 in S4 and the stop of transmitting the energizing signal to the heater 17 in S5.

[0056] The control unit 191 determines whether the selected defrosting mode is a full defrosting mode (or a partial defrosting mode) (S8). If the selected defrosting mode is a full defrosting mode (S8: YES), the control unit 191 starts transmitting a first energizing signal to the inverter 153, instructing the magnetron 152 to supply power at a first output intensity (S9). After the first energizing time determined in S7 has elapsed, the control unit 191 stops transmitting the first energizing signal to the inverter 153 (S10). The control unit 191 starts transmitting a second energizing signal to the inverter 153, instructing the magnetron 152 to supply power at a second output intensity (S11). After the second energizing time determined in S7 has elapsed, the control unit 191 stops transmitting the second energizing signal to the inverter 153 (S12) and terminates the process.

[0057] If the selected defrosting mode is not the full defrosting mode (S8:NO), i.e., the partial defrosting mode, the control unit 191 starts sending an energizing signal to the inverter 153 instructing the magnetron 152 to supply power to output at the output intensity determined in S6 (S13). After the energizing time determined in S7 has elapsed, the control unit 191 stops sending the energizing signal to the inverter 153 (S14) and terminates the process. The cooking appliance 1 is equipped with an infrared sensor that detects the temperature of the object to be heated, and the control unit 191 may stop sending the energizing signal to the magnetron 152 if the temperature detected by the infrared sensor exceeds a predetermined value (for example, 40 degrees). This prevents overheating of the object to be heated.

[0058] With the above configuration and process, in the heating cooker 1, the heater 17 is energized to raise the temperature inside the inner box 13 and the object to be heated, and then the magnetron 152 is energized to irradiate the object to be heated with microwaves. As a result, the amount of liquid free water contained in the object to be heated is increased before the microwaves are irradiated, so that the frozen object to be heated can be efficiently thawed.

[0059] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the claims and scope equivalent to the claims. Furthermore, the independent and dependent claims described in the claims can be combined with each other in any combination, regardless of the form of reference. In addition, the claims use a multi-claim format in which claims refer to two or more other claims (multi-claim format), but are not limited to this. They may also be described using a multi-claim format in which at least one multi-claim refers to another multi-claim (multi-multi-claim format). [Explanation of Symbols]

[0060] 1:Heating cooker 2:Heating chamber 3: Cooking dish 10: Antenna Room 11: Outer box 12: Door 13: Inner box 14: Bulkhead 15: Irradiation device 17: Heater 18: Converter 19: Control circuit 19a: Temperature sensor 19b: Operation panel 121: Handle 122:Operation unit 123: Start button 151: Rotating antenna 152: Magnetron 153: Inverter 191: Control Unit 192: Storage section 193: Input / Output Interface P: Program S: Household power supply T1: Heater power-on time table T2: Magnetron output strength table T3: Magnetron energizing time table

Claims

1. An inner box for containing the object to be heated, A temperature sensor for detecting the temperature inside the inner box, A magnetron that irradiates microwaves when an electric current is applied, A heater that generates heat when electricity is applied and A control unit that controls the supply of power to the magnetron and the heater. Equipped with, The control unit, Based on the temperature detected by the temperature sensor, the energizing time of the heater is determined. After energizing the heater, energizing the magnetron. Heating cooker.

2. The control unit determines that the lower the temperature inside the inner box, the longer the energizing time of the heater. A heating appliance according to claim 1.

3. The control unit, The system accepts input for the amount of the object to be heated to be contained in the inner box. The energizing time of the magnetron is determined according to the input amount. A heating appliance according to claim 1 or 2.

4. The control unit, The system accepts input for the selection of heating intensity. The output intensity of the magnetron is determined according to the selected heating intensity. A heating appliance according to claim 1 or 2.

5. The control unit, The magnetron is first made to output at a first output intensity, and then to output at a second output intensity that is weaker than the first output intensity. A heating appliance according to claim 1 or 2.

6. The control unit, The system accepts input for the amount of the object to be heated to be contained in the inner box. The greater the input amount, the longer the energizing time of the magnetron at the first output intensity is determined, and the shorter the energizing time of the magnetron at the second output intensity is determined. A cooking appliance according to claim 5.

7. The control unit, The system accepts input for selecting the decompression mode. If the first defrosting mode is selected, the magnetron is made to output at a first output intensity, and then at a second output intensity that is weaker than the first output intensity. When the second defrosting mode is selected, the magnetron is made to output at a constant output intensity. A heating appliance according to claim 1 or 2.

8. An inner box for containing the object to be heated, A temperature sensor for detecting the temperature inside the inner box, A magnetron that irradiates microwaves when an electric current is applied, A heater that generates heat when electricity is applied and A control unit that controls the supply of power to the magnetron and the heater. A control method for a heating appliance, comprising: The control unit, Based on the temperature detected by the temperature sensor, the energizing time of the heater is determined. After energizing the heater, energizing the magnetron. Control method.

9. An inner box for containing the object to be heated, A temperature sensor for detecting the temperature inside the inner box, A magnetron that irradiates microwaves when an electric current is applied, A heater that generates heat when electricity is applied and A control unit that controls the supply of power to the magnetron and the heater. A computer program that can be executed in a cooking appliance equipped with the following features: The control unit, Based on the temperature detected by the temperature sensor, the energizing time of the heater is determined. After energizing the heater, energizing the magnetron. A computer program that executes a process.

Images