Heating cooker

Abstract

To alleviate a rush current in a heating cooker which uses heaters having different characteristics, with an inexpensive structure.SOLUTION: A toaster oven 1 as a heating cooker has: a first heater 6; a second heater 7; a first relay 11 for turning on / off electric conduction to the first heater 6; a second relay 12 for turning on / off electric conduction to the second heater 7; and a relay drive circuit 13 for allowing each of the relays 11, 12 to operate. The first heater 11 is a halogen lamp heater in which a resistance value change is large with respect to the temperature change. The second heater 7 is a carbon heater in which a resistance value change is small with respect to the temperature change. In the case where electricity is conducted to both first heater 6 and second heater 7, after turning on the first relay 11, the second relay 12 is turned on after the elapse of one second; thereby, the peak value of the rush current in the entire heater of the toaster oven 1 can be lowered.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a cooking device such as a toaster oven, and more particularly to a cooking device having a plurality of types of heaters. [Background technology]

[0002] Conventionally, as this type of cooking device, a toaster oven is known that has a near-infrared heater having a radiation peak in a wavelength band of 1.5 μm or less and a far-infrared heater having a radiation peak in a wavelength band of more than 1.5 μm, and has a control means for energizing these heaters simultaneously or individually. With this configuration, the inside of the food to be cooked can be heated by the near-infrared rays, and the surface of the food can be browned by the far-infrared rays, making it possible to cook faster. Note that a lamp heater such as a halogen lamp heater is used as the near-infrared heater. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-55376 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the lamp heater has a large change in resistance with temperature change, and therefore the resistance is low immediately after power is applied, i.e., when the heater temperature is low, and as a result, a large inrush current occurs immediately after power is applied. This inrush current may trip the breaker in the switchboard.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to solve the above problems and to reduce the inrush current in a cooking device using heaters with different characteristics with an inexpensive configuration. [Means for solving the problem]

[0006] The cooking device according to claim 1 of the present invention is a cooking device having a first heater, a second heater, a first relay which turns on and off the power supply to the first heater, a second relay which turns on and off the power supply to the second heater, and a relay drive circuit which operates each of the relays, wherein the first heater is a heater which has a large change in resistance value with respect to a change in temperature, and the second heater is a heater which has a small change in resistance value with respect to a change in temperature, and when power is supplied to both the first heater and the second heater, the relay drive circuit controls the second relay to be turned on a predetermined time after turning on the first relay.

[0007] In addition, the heating cooking device described in claim 2 of the present invention is characterized in that, in claim 1, a plurality of the first heaters are provided in parallel, a plurality of first relays are provided for turning on and off the power supply to these first heaters, and the relay drive circuit controls the plurality of first relays to be turned on with a predetermined time difference.

[0008] Furthermore, the cooking device according to claim 3 of the present invention is the cooking device according to claim 1, characterized in that the first heater is a lamp heater, and the second heater is a carbon heater. Effect of the Invention

[0009] The cooking device according to claim 1 of the present invention is configured as described above, so that first, the first heater, which has a large change in resistance value relative to a change in temperature, is energized, and then the second heater, which has a small change in resistance value relative to a change in temperature, is energized. At the moment when the first heater is energized, an inrush current occurs, but at this moment, the second heater is not energized, so that the peak value of the inrush current can be reduced by the amount of the current flowing through the second heater. Then, after a predetermined time has elapsed, the second heater is energized, but almost no inrush current occurs in this second heater. Therefore, almost no inrush current occurs at the moment when all the heaters are energized. As a result, the peak value of the inrush current of the entire heater can be reduced, and the risk of the breaker of the distribution board being tripped can be reduced.

[0010] In addition, by providing a plurality of first heaters in parallel and a plurality of first relays which respectively turn on and off the power supply to these first heaters, and by controlling the relay drive circuit to turn on the plurality of first relays with a predetermined time difference, if the total output of the first heaters is the same, the peak value of the inrush current of each of the first heaters can be lowered compared to when there is a single first heater, and the timing at which the inrush current occurs can be dispersed, thereby lowering the peak value of the inrush current of the entire heaters of the heating and cooking device.

[0011] Furthermore, by using a lamp heater as the first heater and a carbon heater as the second heater, it is possible to generate infrared rays with different wavelength characteristics while keeping the peak value of the inrush current of the entire heater low, and to heat and cook the food in the heating and cooking device well. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view of a cooking device according to a first embodiment of the present invention. [Diagram 2] FIG. [Diagram 3]10 is an explanatory diagram showing the waveform of the current flowing through the entire heater when heating starts, and the ON timing of each relay. FIG. [Figure 4] 10 is an explanatory diagram showing the waveform of the current flowing through the entire heater during heating and the ON timing of each relay. FIG. [Diagram 5] FIG. 4 is a cross-sectional view of a cooking device according to a second embodiment of the present invention. [Figure 6] FIG. [Figure 7] 10 is an explanatory diagram showing the waveform of the current flowing through the entire heater when heating starts, and the ON timing of each relay. FIG. [Figure 8] 10 is an explanatory diagram showing the waveform of the current flowing through the entire heater during heating and the ON timing of each relay. FIG. [Figure 9] FIG. 13 is a schematic explanatory diagram of an electric circuit in a conventional cooking device. [Figure 10] 10 is an explanatory diagram showing the waveform of a current flowing through an entire heater and the ON timing of each relay in a conventional cooking device. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A first embodiment of the present invention will be described below with reference to Figs. 1 to 4. 1 is a toaster oven as a cooking device of the present invention. This toaster oven 1 is configured to have a main body 2 and a door body 3. The main body 2 has a baking chamber 4 formed therein and an opening 5 on the front side. The opening 5 can be opened and closed by the door body 3. A first heater 6, a second heater 7, and a grill 8 are provided in the baking chamber 4. The first heater 6 is provided below the grill 8. The second heater 7 is provided above the grill 8. The grill 8 is configured to be pulled forward as the door body 3 is opened, and pushed backward as the door body 3 is closed. 9 is a handle that is gripped when opening and closing the door body 3.

[0014] The first heater 6 is a lamp heater, and in this embodiment, it is called a halogen lamp heater. Although not shown, the halogen lamp heater is a heater in which a filament such as tungsten is inserted into a glass tube and halogen gas is sealed in the glass tube. That is, the halogen lamp heater has the same structure as an incandescent light bulb. Tungsten, which is the material of the filament of the halogen lamp heater, has a characteristic that the higher the temperature, the higher the electric resistance value, and the electric resistance value at the temperature when heating is 10 times or more compared to the electric resistance value at room temperature. Therefore, the first heater 6, which is a halogen lamp heater, is likely to have a large inrush current flow at the moment when electricity starts to be applied. On the other hand, the second heater 7 is a carbon heater. Although not shown, the carbon heater is a heater in which a carbon heating element is inserted into a glass tube and an inert gas is sealed in the glass tube. The carbon heating element has a small difference between the electric resistance value at room temperature and the electric resistance value at the temperature when heating is performed. Therefore, almost no inrush current flows through the second heater 7, which is a carbon heater, when the power supply starts.

[0015] 2 is a schematic diagram of the electric circuit of the toaster oven 1. As shown in this figure, the first heater 6 and the second heater 7 are connected in parallel to an AC power source 10. A first relay 11 is connected in series with the first heater 6. Similarly, a second relay 12 is connected in series with the second heater 7. The first relay 11 and the second relay 12 are both normally open. A relay drive circuit 13 is provided to operate these relays 11 and 12. Reference numeral 14 denotes a control circuit, 15 denotes an operation unit, 16 denotes a display unit, and 17 denotes a temperature sensor that detects the temperature inside the baking chamber 4.

[0016] Next, the operation of this embodiment will be described. First, a user connects a power plug (not shown) to the AC power source 10, opens the door 3, places the food to be cooked, such as bread, on the grill 8, and then closes the door 3. Then, by operating the operation unit 15, the control circuit 14 turns on the normally open relays 11 and 12 via the relay drive circuit 13. To explain in more detail, the relay drive circuit 13 first turns on the first relay 11, and one second later turns on the second relay 12.

[0017] By turning on each of the relays 11 and 12 in this way, a current flows through the entire heater of the toaster oven 1 as shown in FIG. 3. That is, at the moment when the first relay 11 is turned on, an inrush current flows through the first heater 6. At this point, the current flowing through the first heater 6 becomes the current flowing through the heater of the toaster oven 1. The inrush current at this time is an inrush current flowing through only the first heater 6, so it can be kept relatively small. This inrush current decreases over time. Then, the current flowing through the heater of the toaster oven 1 converges to the rated current value of the first heater 6 within one second until the second relay 12 is turned on. Next, when the second relay 12 is turned on, no inrush current flows through the second heater 7, and a current of the rated current value flows from the beginning. At this point, a current flows through all the heaters of the toaster oven 1. Therefore, the moment second relay 12 is turned on, a current equal to the total of the rated current values ​​of the individual heaters flows through the heaters of toaster oven 1 as a whole.

[0018] In this way, when the first heater 6 and the second heater 7 are energized and the temperature in the baking chamber 4 rises, the first heater 6 and the second heater 7 are controlled to be turned on and off based on the temperature in the baking chamber 4 detected by the temperature sensor 17. At this time, depending on the contents of the program, the first heater 6, which is a halogen lamp heater that radiates a lot of near infrared rays, and the second heater 7, which is a carbon heater that radiates a lot of far infrared rays, are individually controlled to be turned on and off, so they are not necessarily controlled to be turned on and off at the same timing. However, when it is time for both the first heater 6 and the second heater 7 to change from an off state to an on state almost simultaneously, the first heater 6 is energized by turning on the first relay 11, as at the start of heating, and then the second heater 7 is energized by turning on the second relay 12 after a 1-second interval. Also, when it is time to energize the first heater 6 while the second heater 7 is energized, the second relay 12 may be turned off once, the first relay 11 may be turned on, and the second relay 12 may be turned on again one second later, as shown in Fig. 4. Even during on / off control of the first heater 6, an inrush current flows through the first heater 6 the moment the first relay 11 is turned on, so by energizing the first heater 6 and the second heater 7 with a time lag, the inrush current of the entire heater of the toaster oven 1 can be mitigated. However, unlike when heating starts, the filament of the first heater 6 is in a slightly warm state, so the inrush current during on / off control is smaller than the inrush current at the start of heating.

[0019] In this way, the first heater 6, which is a halogen lamp heater that radiates a large amount of near infrared rays, and the second heater 7, which is a carbon heater that radiates a large amount of far infrared rays, can effectively heat food items such as bread placed on the grill 8. In particular, by appropriately controlling the first heater 6 and the second heater 7, food items can be heated appropriately according to the type of food item.

[0020] As described above, in the present invention, in a toaster oven 1 serving as a cooking device having a first heater 6, a second heater 7, a first relay 11 which turns on and off the power supply to the first heater 6, a second relay 12 which turns on and off the power supply to the second heater 7, and a relay drive circuit 13 which operates the relays 11 and 12, when the first heater 11 is a halogen lamp heater having a large change in resistance value relative to a change in temperature and the second heater 7 is a carbon heater having a small change in resistance value relative to a change in temperature, and when power is supplied to both the first heater 6 and the second heater 7, the relay drive circuit 13 controls the second relay 12 to turn on one second after turning on the first relay 11, thereby lowering the peak value of the inrush current of the entire heater of the toaster oven 1 and reducing the risk of the breaker of the distribution board tripping.

[0021] Furthermore, in the present invention, by using a halogen lamp heater as the first heater 6 and a carbon heater as the second heater 7, it is possible to generate infrared rays with different wavelength characteristics while keeping the peak value of the inrush current of the entire heater of the toaster oven 1 low, and to heat and cook the food in the toaster oven 1 well.

[0022] Next, a second embodiment of the present invention will be described with reference to Figs. 5 to 8. Reference numeral 21 denotes a toaster oven as a cooking device of the present invention. This toaster oven 21 is configured to have a main body 22 and a door body 3. The main body 22 has a baking chamber 24 formed therein and an opening 25 on the front side. The opening 25 can be opened and closed by the door body 3. In addition, two first heaters 26a, 26b, two second heaters 27a, 27b, and a grill 8 are provided in the baking chamber 24. The first heaters 26a, 26b are provided below the grill 8 and are aligned in the front-rear direction. The second heaters 27a, 27b are provided above the grill 8 and are aligned in the front-rear direction. Furthermore, the grill 8 is configured to be pulled forward as the door body 3 opens, and pushed backward as the door body 3 closes. In addition, reference numeral 9 denotes a handle that is grasped when opening and closing the door body 3.

[0023] Both of the first heaters 26a and 26b are lamp heaters, and in this embodiment, both are called halogen lamp heaters. Although not shown, the halogen lamp heater is a heater in which a filament such as tungsten is inserted into a glass tube and halogen gas is sealed in the glass tube. That is, the halogen lamp heater has the same structure as an incandescent light bulb. Tungsten, which is the material of the filament of the halogen lamp heater, has a characteristic that the higher the temperature, the higher the electric resistance value, and the electric resistance value at the temperature when heating is 10 times or more compared to the electric resistance value at room temperature. Therefore, the first heaters 26a and 26b, which are halogen lamp heaters, are prone to a large inrush current at the moment of starting to be energized. On the other hand, both of the second heaters 27a and 27b are carbon heaters. Although not shown, the carbon heater is a heater in which a carbon heating element is inserted into a glass tube and an inert gas is sealed in the glass tube. The carbon heating element has a small difference between its electrical resistance at room temperature and its electrical resistance at the temperature at which it heats up, so that almost no inrush current flows through the second heaters 27a and 27b, which are carbon heaters, when power is first applied.

[0024] FIG. 6 is a schematic diagram of the electric circuit of the toaster oven 21. As shown in this figure, the first heaters 26a, 26b and the second heaters 27a, 27b are connected in parallel to the AC power source 10. The first heater 26a and the first heater 26b are also connected in parallel to the AC power source 10. The second heaters 27a, 27b are connected in series. A first relay 31a is connected in series to the first heater 26a. Similarly, a first relay 31b is connected in series to the first heater 26b. Furthermore, a second relay 32 is connected in series to the series circuit of the second heaters 27a, 27b. The first relays 31a, 31b and the second relay 32 are each a normally open type. A relay drive circuit 33 for operating these relays 31a, 31b, 32 is provided. Reference numeral 14 denotes a control circuit, 15 denotes an operation unit, 16 denotes a display unit, and 17 denotes a temperature sensor for detecting the temperature inside the baking chamber 24.

[0025] Next, the operation of this embodiment will be described. First, a user connects a power plug (not shown) to the AC power source 10, opens the door 3, places the food to be cooked, such as bread, on the grill 8, and then closes the door 3. Then, by operating the operation unit 15, the control circuit 14 turns on the normally open relays 31a, 31b, and 32 via the relay drive circuit 33. More specifically, the relay drive circuit 33 first turns on the first relay 31a, turns on the first relay 31b one second later, and turns on the second relay 32 one second later.

[0026] By turning on each of the relays 31a, 31b, and 32 in this way, a current flows through the entire heater of the toaster oven 21 as shown in FIG. 7. That is, the moment the first relay 31a is turned on, an inrush current flows through the first heater 26a. At this point, the current flowing through the first heater 26a becomes the current flowing through the heater of the toaster oven 21. The inrush current at this time is an inrush current flowing through the first heater 26a alone, so it can be kept relatively small. This inrush current decreases over time. The current flowing through the heater of the toaster oven 21 converges to the rated current value of the first heater 26a within one second until the first relay 31b is turned on. Next, the moment the first relay 31b is turned on, an inrush current flows through the first heater 26b. At this time, the current flowing through the first heaters 26a and 26b becomes the current flowing through the heaters of the toaster oven 21. The inrush current at this time is an inrush current flowing through only the first heater 26b, so it can be kept relatively small. This inrush current decreases over time. The current flowing through the heaters of the toaster oven 21 converges to the total value of the rated current values ​​of the first heaters 26a and 26b within one second until the second relay 32 is turned on. Furthermore, when the second relay 32 is turned on, no inrush current flows through the second heaters 27a and 27b, and a current of the rated current value flows from the beginning. At this time, a current flows through all the heaters of the toaster oven 21. Therefore, at the moment when the second relay 32 is turned on, a current that is the total value of the rated current values ​​of the heaters flows through the entire heaters of the toaster oven 21.

[0027] In this way, when the first heaters 26a, 26b and the second heaters 27a, 27b are energized and the temperature in the baking chamber 24 rises, the first heaters 26a, 26b and the second heaters 27a, 27b are on / off controlled based on the temperature in the baking chamber 24 detected by the temperature sensor 17. At this time, depending on the contents of the program, the first heaters 26a, 26b, which are halogen lamp heaters that radiate a lot of near infrared rays, and the second heaters 27a, 27b, which are carbon heaters that radiate a lot of far infrared rays, are individually on / off controlled, so they are not necessarily on / off controlled at the same timing. However, when the first heaters 26a, 26b are on / off controlled, the first relay 31a is turned on to energize the first heater 26a, as at the start of heating, and one second later, the first relay 31b is turned on to energize the first heater 26b. Even during on / off control of the first heaters 26a, 26b, an inrush current flows through the first heaters 26a, 26b the moment the first relays 31a, 31b are turned on, so that the inrush current of the entire heater of the toaster oven 21 can be mitigated by energizing the first heaters 26a and 26b with a time lag. However, unlike when heating starts, the filaments of the first heaters 26a, 26b are in a slightly warm state, so the inrush current during on / off control is smaller than the inrush current at the start of heating. Note that when the first heaters 26a, 26b are on / off controlled, the timings at which they are both turned off may be simultaneous or may be shifted by one second.

[0028] In addition, when it is time to energize the first heaters 26a, 26b while the second heaters 27a, 27b are energized, the first relay 31a is first turned on to energize the first heater 26a, and one second later, the first relay 31b is turned on to energize the first heater 26b. In this case, since the inrush currents generated individually in the first heaters 26a, 26b are relatively small, the peak value of the inrush current can be reduced for the entire heater of the toaster oven 21. In this case, as shown in FIG. 8, the second relay 32 may be turned off once, the first relay 31a may be turned on, the first relay 31b may be turned on one second later, and the second relay 12 may be turned on again one second later. By controlling in this manner, the peak value of the inrush current can be reduced for the entire heater of the toaster oven 21.

[0029] In this way, the first heaters 26a, 26b, which are halogen lamp heaters that radiate a lot of near infrared rays, and the second heaters 27a, 27b, which are carbon heaters that radiate a lot of far infrared rays, can satisfactorily heat food items such as bread placed on the grill 8. In particular, by appropriately controlling the first heaters 26a, 26b and the second heaters 27a, 27b, the food items can be heated appropriately according to the type of food item.

[0030] As described above, the present invention provides a toaster oven 21 as a cooking device having first heaters 26a, 26b, second heaters 27a, 27b, first relays 31a, 31b which turn on and off the power supply to the first heaters 26a, 26b, a second relay 32 which turns on and off the power supply to the second heaters 27a, 27b, and a relay drive circuit 33 which operates the relays 31a, 31b, 32, wherein the first heaters 31a, 31b are halogen lamps which have a large change in resistance value relative to a change in temperature. When the first heater 26a, 26b and the second heater 27a, 27b are carbon heaters whose resistance change with temperature is small, and when current is applied to both the first heater 26a, 26b and the second heater 27a, 27b, the relay drive circuit 33 controls the second relay 32 to turn on one second after turning on the first relays 31a, 31b, thereby lowering the peak value of the inrush current of the entire heater of the toaster oven 21 and reducing the risk of the breaker in the distribution board tripping.

[0031] Furthermore, in the present invention, two first heaters 26a, 26b are provided in parallel, and two first relays 31a, 31b are provided which respectively turn on and off the power to first heaters 26a, 26b. Also, the relay drive circuit 33 controls the first relays 31a, 31b to be turned on with a time difference of one second. Thus, if the total output of the first heaters 26a, 26b is the same as the output of the single first heater 6 shown in the first embodiment, the peak value of the inrush current of each of the first heaters 26a, 26b can be lowered compared to the first heater 6, and the timing at which the inrush current occurs can be dispersed. As a result, the peak value of the inrush current of the entire heaters of the toaster oven 21 can be lowered.

[0032] Furthermore, in the present invention, by using halogen lamp heaters as the first heaters 6a, 6b and carbon heaters as the second heaters 7a, 7b, it is possible to generate infrared rays with different wavelength characteristics while keeping the peak value of the inrush current of the entire heater of the toaster oven 21 low, and to heat and cook the food in the toaster oven 21 well.

[0033] Next, for comparison with this embodiment, a conventional technique will be described with reference to Figures 9 and 10. Note that, similarly to the second embodiment, the structure has two first heaters and two second heaters.

[0034] Both of the first heaters 106a and 106b are lamp heaters, and in this comparative example, both are called halogen lamp heaters. That is, as described in the above embodiments, a large inrush current is likely to flow through the first heaters 106a and 106b at the moment when power is first applied. On the other hand, both of the second heaters 107a and 107b are carbon heaters. That is, as described in the above embodiments, almost no inrush current flows through the second heaters 107a and 107b at the moment when power is first applied.

[0035] FIG. 9 is a schematic diagram of the electric circuit of the toaster oven. As shown in this figure, the series circuit of the first heaters 106a and 106b and the series circuit of the second heaters 107a and 107b are connected in parallel to the AC power source 10. A first relay 111 is connected in series with the series circuit of the first heaters 106a and 106b. Similarly, a second relay 112 is connected in series with the series circuit of the second heaters 107a and 107b. The first relay 111 and the second relay 112 are each of normally open type. A relay drive circuit 113 for operating these relays 111 and 112 is provided. 114 is a control circuit, 115 is an operation unit, 116 is a display unit, and 117 is a temperature sensor for detecting the temperature inside the baking chamber.

[0036] Next, the operation of this comparative example will be described. First, a user connects a power plug (not shown) to the AC power source 10, opens the door, places the food to be cooked, such as bread, on the grill, and then closes the door. Then, by operating the operation unit 115, the control circuit 114 turns on the normally open relays 111 and 112 via the relay drive circuit 113. More specifically, the relay drive circuit 113 turns on the first relay 111 and the second relay 112 at the same time.

[0037] By turning on the relays 111 and 112 simultaneously in this way, a current flows through the entire heater of the toaster oven as shown in FIG. 10. That is, at the moment when the first relay 111 and the second relay 112 are turned on simultaneously, an inrush current flows through the first heaters 106a and 106b at the same time. The inrush current at this time is the sum of the inrush current flowing through the first heater 106a and the inrush current flowing through the first heater 106b, and is therefore relatively large. For this reason, depending on the specifications of the distribution board in the user's house, there is a risk that the breaker will be cut off. This inrush current decreases over time. Then, the current flowing through the entire heater of the toaster oven converges to the sum of the rated current values ​​of the first heaters 106a and 106b and the second heaters 107a and 107b.

[0038] In this way, when the first heaters 106a, 106b and the second heaters 107a, 107b are energized and the temperature in the baking chamber rises, the first heaters 106a, 106b and the second heaters 107a, 107b are controlled to be on and off based on the temperature in the baking chamber detected by the temperature sensor 117. At this time, depending on the contents of the program, the first heaters 106a, 106b, which are halogen lamp heaters that radiate a lot of near infrared rays, and the second heaters 107a, 107b, which are carbon heaters that radiate a lot of far infrared rays, are individually controlled to be on and off, so they are not necessarily controlled to be on and off at the same timing. However, since the first heaters 106a, 106b are connected in series, when the first heaters 106a, 106b are controlled to be on and off, the first heaters 106a, 106b are always energized at the same time by turning on the first relay 111. In addition, the first heaters 106a, 106b and the second heaters 107a, 107b may both change from the OFF state to the ON state at approximately the same time, or the first heaters 106a, 106b may change to the ON state when the second heaters 107a, 107b are in the ON state. Even during ON / OFF control of the first heaters 106a, 106b, an inrush current flows through the first heaters 106a, 106b the moment the first relay 111 is turned ON, so that the inrush current of the entire heater of the toaster oven becomes large. Unlike when heating starts, the filaments of the first heaters 106a, 106b are in a slightly warm state, so the inrush current during on / off control is smaller than the inrush current at the start of heating. However, since it is the sum of the inrush currents of the two first heaters 106a, 106b, a large inrush current still flows through the entire heater of the toaster oven.

[0039] The present invention is not limited to the above-mentioned embodiment, and various modifications are possible within the scope of the gist of the invention. For example, in the second embodiment, two first and two second heaters are provided, but three or more heaters may be provided, and the number of the first and second heaters may be different. The type of the first heater and the type of the second heater can be appropriately selected. In each of the above-mentioned embodiments, the interval between the energization start timings of the heaters is one second, but the point is that it is sufficient that there is a sufficient time for the inrush current to converge to the rated current value, and other times, such as 0.5 seconds or 2 seconds, may be used. Furthermore, in the second embodiment, the first heater 26a is always controlled to be turned on first, but the first heater 26b may be controlled to be switched on first. [Explanation of symbols]

[0040] 1,21 Toaster oven (heating cooking device) 6, 26a, 26b First heater 7, 27a, 27b Second heater 11,31a,31b First relay 12,32 Second Relay 13,33 Relay drive circuit

Claims

1. A cooking device having a first heater, a second heater, a first relay for turning on and off current to the first heater, a second relay for turning on and off current to the second heater, and a relay drive circuit for operating each of the relays, A cooking device characterized in that the first heater is a heater having a large change in resistance value with respect to a change in temperature, and the second heater is a heater having a small change in resistance value with respect to a change in temperature, and when current is applied to both the first heater and the second heater, the relay drive circuit controls the first relay to be turned on after a predetermined time has passed since the first relay was turned on.

2. 2. The cooking device according to claim 1, characterized in that a plurality of the first heaters are provided in parallel, a plurality of first relays are provided for turning on and off the power supply to the first heaters, respectively, and the relay drive circuit controls the plurality of first relays to be turned on with a predetermined time difference.

3. 2. The cooking device according to claim 1, wherein the first heater is a lamp heater and the second heater is a carbon heater.

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