JP2007280941A - Heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating cooker with an induction heating coil arranged beneath a top panel capable of effectively cooking by restricting the output of the induction heating coil adequately in response to the material and thickness of a cooking container when a temperature of the induction heating coil increases higher than a predetermined temperature. <P>SOLUTION: The heating cooker includes the top panel for mounting the cooking container, the induction heating coil mounted beneath the top panel, a temperature sensor for detecting a temperature of the heating coil, an inverter circuit for supplying power to the induction heating coil, a coil current detection circuit for detecting a current flowing the induction heating coil, a control means for controlling the inverter circuit or the like based on an output of the coil current detection circuit, and an output of a temperature sensor or the like. The control means is structured so as to set an upper limit value of the current flowing the induction heating coil in response to a coil temperature detected by the temperature sensor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cooking device in which an induction heating coil is disposed below a top plate that heats a cooking container.

For example, in a heating cooker such as an electromagnetic cooker, a top plate made of heat-resistant glass is attached to the top of the appliance body, an induction heating coil is placed under this top plate, and cooking is performed above the induction heating coil on the top plate. In the case of performing induction heating by placing a cooking container such as a pot, as shown in Patent Document 1, for example, the temperature of the induction heating coil is detected by a temperature detection element, and when the heating coil is overheated, the output of the inverter circuit There are some which prevent damage due to overheating of the heating coil.
JP 2000-223251 A

  On the other hand, in the configuration shown in Patent Document 1, since the input current of the heating coil is simply controlled according to the temperature of the heating coil, the output is reduced more than necessary depending on the material of the cooking container, and the cooking time is reduced. There is a problem that it becomes longer or affects the finish of cooking.

  Therefore, the present invention aims to perform efficient heating cooking by appropriately limiting the output of the induction heating coil according to the material of the cooking container when the temperature of the induction heating coil rises above a predetermined temperature. It is what.

  According to a first aspect of the present invention, there is provided a top plate on which the cooking container is placed, an induction heating coil mounted below the top plate, a temperature sensor for detecting the temperature of the heating coil, and the induction heating coil. An inverter circuit for supplying power, a coil current detection circuit for detecting a current flowing through the induction heating coil, and a control means for controlling the inverter circuit and the like based on the output of the coil current detection circuit, the output of the temperature sensor, etc. In this case, the control means is configured to set an upper limit value of the current flowing through the induction heating coil in accordance with the coil temperature detected by the temperature sensor.

  According to a second aspect of the present invention, in the configuration of the first aspect, an operation unit for setting the output of the induction heating coil is provided, and the control means is connected to the induction heating coil when the temperature of the induction heating coil exceeds a set value. After reducing the flowing current, when the temperature of the induction heating coil falls below the set value, the current flowing through the induction heating coil is controlled by approaching the set value of the output of the induction heating coil. It is.

  According to a third aspect of the present invention, in the configuration of the second aspect, the control means is configured to control a current flowing through the induction heating coil based on an output that can be set by the operation unit. .

  According to a fourth aspect of the present invention, there is provided a top plate for placing the cooking vessel, an induction heating coil mounted below the top plate, a temperature sensor for detecting the temperature of the cooking vessel, and power to the induction heating coil. An inverter circuit for supplying current, a coil current detection circuit for detecting a current flowing through the induction heating coil, and a control means for controlling the inverter circuit and the like based on the output of the coil current detection circuit, the output of the temperature sensor, etc. In what is provided, this control means is configured to set an upper limit value of the current flowing in the induction heating coil in accordance with the temperature of the cooking container detected by the temperature sensor.

  According to the fifth aspect of the present invention, in the configuration of the fourth aspect, the operation unit for setting the output of the induction heating coil is provided, and the control means flows through the induction heating coil when the temperature of the cooking container exceeds the set value. When the temperature of the cooking container is lowered from the set value by reducing the current, the current flowing in the induction heating coil is controlled by approaching the set value of the output of the induction heating coil. .

  According to a sixth aspect of the present invention, in the configuration of the fifth aspect, the control means is configured to control the current flowing through the induction heating coil based on the output that can be set by the operation unit.

  According to the seventh aspect of the present invention, in the configuration of the second or fifth aspect, the control means may be configured so that the temperature of the cooking container is reduced even when the temperature of the cooking container exceeds the set value and the current flowing through the induction heating coil is reduced. When the value does not fall below the set value, the power supply to the induction heating coil is stopped.

  According to the configuration of the first aspect of the present invention, the upper limit value of the coil current flowing through the induction heating coil is set according to the coil temperature of the induction heating coil, so that the heating coil is set according to the temperature of the heating coil. The current flowing in the coil can be accurately limited, and damage due to an increase in coil temperature can be reliably prevented.

  With the configuration according to claim 2 of the present invention, when the temperature of the induction heating coil rises and the current flowing through the induction heating coil is limited, the value of the current flowing through the induction heating coil is set based on the set output. By doing so, heating suitable for cooking can be performed.

  According to the configuration described in claim 3 of the present invention, the control means is configured to control the current flowing in the induction heating coil based on the output that can be set by the operation unit, so that it can be used according to the type of cooking. The output of the induction heating coil is controlled so as to approach the output set by the person, and the food suitable for cooking can be heated as much as possible.

  According to the fourth aspect of the present invention, the temperature of the cooking container is detected by the temperature sensor, and the output of the induction heating coil is controlled according to the temperature of the cooking container. By setting the upper limit value of the current value flowing through the induction heating coil according to the above, the amount of heat generated by the induction heating coil can be accurately controlled according to the temperature of the cooking container.

  According to the configuration of claim 5 of the present invention, when the temperature of the cooking container is reduced by reducing the current flowing through the induction heating coil beyond the preset value, the output setting is set. By configuring the current flowing in the induction heating coil so as to approach the value, the food can be heated with the heating amount based on the setting. It can be suppressed as much as possible.

  According to the configuration of the sixth aspect of the present invention, cooking is performed with a heating amount close to the setting of the user by controlling the current flowing through the induction heating coil based on the output that can be set by the operation unit. It is possible.

  According to the seventh aspect of the present invention, when the temperature of the cooking container does not decrease even when the temperature of the cooking container exceeds the set value and the current flowing through the induction heating coil is reduced, the energization to the induction heating coil is performed. By stopping the operation, it is possible to prevent damage due to overheating of the induction heating coil and cooking errors due to overheating of the cooking container while performing output control of the induction heating coil suitable for the material of the cooking container.

  First, an embodiment according to the present invention will be described with reference to FIG. 1. Reference numeral 1 denotes a cooker body of an electromagnetic cooker that is used in a drop-in manner, for example, in a system kitchen or the like. And a pair of left and right induction heating coils 3 and 4 and a radiant heater 5 are incorporated in the lower part of the top plate as a heat source.

  On the other hand, an operation panel 6 is disposed on the right side of the front surface of the electromagnetic cooker body 1, and a grill door 8 for the grill 7 is disposed on the left side of the operation panel so that it can be pulled out. Are provided with a seesaw type power switch 9, a plurality of operation keys 10,..., A push-push type operation knob 11,. When the operation knobs 11 are pulled out by a push operation, the induction heating coils 3 and 4, the radiant heater 5 and the grill heater (not shown) in the grill 7 are energized. It is configured to set the heating power, cooking time, cooking temperature, etc. when rotating with.

  In addition, the outer peripheral edge of the top plate 2 is pressed and fixed by the top plate frame 12, and an operation unit 13 constituted by a non-contact type touch key is disposed at the front end of the top plate frame, and the top plate frame A pair of left and right intake / exhaust covers 14, 14 are detachably attached to the rear end of the plate frame 12.

  On the other hand, as shown in FIG. 2, the operation unit 13 arranges touch areas such as a thermal power key 16..., A water heater key 17, a fried food key 18, etc. on the front or back surface of the glass plate 15 by printing. The input operation is detected by an operation circuit board, which will be described later, arranged on the back surface of the glass plate 15, and the operation circuit board detects a change in capacitance due to the contact or proximity of a finger or the like to the touch area. It is configured to detect input operations.

  FIG. 3 shows a part of a circuit block diagram of a control circuit 30 serving as a control means for controlling energization to the induction heating coils 3, 4 and the like. A power supply circuit is connected to a commercial 200 V power supply 31 via a relay contact 32. 33, and a main control circuit 34 constituted by a microcomputer is connected to the output of the power supply circuit, and a voltage detection circuit 35 is connected to the power supply 31 via the power switch 9. The output of the circuit is connected to the input port of the main control circuit 34, and the operation keys 10... Arranged on the operation panel 6 are connected to the input port via the key detection circuit 43.

  An inverter circuit 37 is connected to the relay contact 32 via an input power detection circuit 36, and the induction heating coils 3 and 4 and the current value supplied to the coil are detected at the output of the inverter circuit. A coil current detection circuit 38 is connected, and an output of the input power detection circuit 36 is connected to an input port of the main control circuit 34.

  The output port of the main control circuit 34 is connected to the radiant heater 5 and the upper and lower grill heaters 45, 45 disposed in the grill 7 via a heater drive circuit 44, and via a cooling fan drive circuit 46. A cooling fan 47 mounted in the cooker body 1 is connected, and a relay drive circuit 48 for operating the relay contact 32 is connected.

  Further, an LED lamp 50... For displaying an ON / OFF operation state of the operation keys 10... Arranged on the operation panel 6 is connected to the output port of the main control circuit 34 through the LED drive circuit 49. ing.

  Further, the input / output port of the main control circuit 34 is connected to a memory 53 and a communication circuit 54 constituted by a non-volatile memory for storing various data, and the communication circuit is connected to a sub-control constituted by a microcomputer. The circuit 60 is connected.

  As shown in FIG. 4, the input port of the sub-control circuit 60 includes pan bottom temperature sensors 62 and 62 disposed near the center of the induction heating coils 3 and 4 via the temperature detection circuit 61, and an induction heating coil. The coil temperature sensors 63 and 63 are connected to the induction heating coils so as to detect the temperature of the induction heating coils. The operation unit 13 is connected to the input / output port via the key detection microcomputer 66. Are connected to a hot water key 16, a water heater key 17, a deep-fried food key 18, and the like, and an input operation by these keys is detected by a change in capacitance due to the approach of a finger to these keys.

  Thus, the operation when cooking using the induction heating coils 3 and 4 will be described. After the cooking container 22 such as a pan is placed above the induction heating coils 3 and 4 of the top plate 2 (FIG. 4), the power switch 9 is turned on, and then the knob 11a of the operation panel 6 is pushed and pulled out, and then the knob 11a is rotated, or the knob 11a is pushed and pulled out. By setting the heating power with the keys 16,..., These operations are detected by the main control circuit 34 and the sub-control circuit 60, energization of the induction heating coils 3 and 4 is started, and cooking is started.

  On the other hand, after the start of cooking, as shown in FIG. 5, the temperatures of the induction heating coils 3 and 4 are detected by the outputs of the coil temperature sensors 63 and 63, and the detected temperature exceeds a preset set value T1. If the coil current detected by the coil current detection circuit 38 exceeds 75 A, for example, it is determined whether the coil current exceeds 75 A, and if it exceeds, the upper limit of the coil current flowing through the induction heating coils 3 and 4 is set to 75 A. If not, the control circuit 30 performs control so as to maintain the current value.

  Further, even if the temperature of the induction heating coils 3 and 4 exceeds the set value T1 and the upper limit of the coil current is set to 75 A, the control circuit 30 further increases the temperature of the induction heating coils 3 and 4 and increases T1. Is exceeded, the upper limit of the coil current is set to 65 A, for example, and thereafter the upper limit of the coil current is similarly reduced as the temperature of the induction heating coils 3 and 4 increases.

  In addition, when the temperature of the induction heating coils 3 and 4 falls by setting the upper limit of the coil current, the upper limit value of the coil current is increased in proportion to the temperature drop.

  With these configurations, when the temperature of the induction heating coils 3 and 4 exceeds a predetermined temperature set in advance, the upper limit value of the coil current is set according to this temperature, for example, the heating key of the operation unit 13 Compared with the case where the output set at 16... Is controlled, the current flowing through the induction heating coils 3 and 4 is surely not affected by the change in the coil current due to the difference in the material of the cooking vessel 19. It can be set according to the temperature of the induction heating coils 3 and 4, and accurate output control according to the coil temperature can be performed.

  On the other hand, even if the upper limit value of the coil current is set to a predetermined lower limit value (for example, 35 A in the embodiment), the control circuit 30 sets the upper limit temperature T6 (for example, 280) that is detected by the coil temperature sensors 63 and 63 in advance. When the degree C) is exceeded, the energization to the induction heating coils 3 and 4 is stopped.

  With these configurations, it is possible to prevent damage to the induction heating coils 3 and 4 due to overheating and deterioration of durability while controlling the output of the induction heating coils 3 and 4 suitable for the material of the cooking container.

  FIG. 6 shows changes in the coil current due to the difference in the material of the cooking container 19. When the output of the induction heating coils 3 and 4 is set to 2000 W, for example, with the heating key 16 of the operation unit 13, the thickness is changed. However, the coil current flowing through the induction heating coils 3 and 4 is i1 in the 22 cm enamel pan, i2 in the 18 cm thick SUS18-8, and i3 in the 12 cm thick enamel pan.

  Thereby, for example, even if the output of the induction heating coils 3 and 4 is set to 3000 W and cooking, the temperature of the induction heating coils 3 and 4 rises to the set temperature or more and the upper limit value of the output is set to 2000 W. As described above, since the coil current differs depending on the material and thickness of the cooking container 19, depending on the material, the temperature of the cooking container 19 may be drastically reduced due to excessive reduction of the output, which may affect cooking.

  On the other hand, in the above embodiment, the temperature of the induction heating coils 3 and 4 is detected by the coil temperature sensors 63 and 63, and the upper limit value of the coil current of the induction heating coil is set according to the temperature of the induction heating coil. Similarly, when the temperature of the cooking container 19 is detected by the pan bottom temperature sensors 62 and 62 and the temperature of the cooking container exceeds, for example, the set values T1 to T5, the coil currents of the induction heating coils 3 and 4 correspond to this temperature. The upper limit value may be set.

  With these configurations, the coil currents of the induction heating coils 3 and 4 are appropriately set according to the material and thickness of the cooking vessel 19, and the output of the induction heating coils 3 and 4 is excessively lowered or reduced due to insufficient reduction. Overshoot can be reliably prevented.

  Furthermore, when the induction heating coils 3 and 4 and the cooking container 19 set the upper limit value of the coil current of the induction heating coils 3 and 4 exceeding the set values T1 to T5, the control circuit 30 according to the present invention sets the upper limit of the coil current. When the temperature of the induction heating coils 3 and 4 and the temperature of the cooking container 19 are lowered by setting the value, the upper limit value of the coil current close to the output of the induction heating coils 3 and 4 set by the operation unit 13 is set. It is configured to do.

  Thereby, the damage by the heating of the induction heating coils 3 and 4 can be prevented while preventing the occurrence of cooking mistakes due to insufficient heating of the food due to the coil current limitation.

  On the other hand, even when the temperature of the cooking container 19 is detected by the pan bottom temperature sensors 62 and 62 and the upper limit value of the coil current of the induction heating coils 3 and 4 is set, the coil current of the induction heating coils 3 and 4 is set. Even if the upper limit value is set to a predetermined lower limit value (for example, 35A in the embodiment), if the detected temperature of the pan bottom temperature sensors 62, 62 exceeds a preset upper limit temperature T6 (for example, 260 degrees C), The energization to the induction heating coils 3 and 4 is stopped.

  With these configurations, when the temperature of the cooking vessel 19 rises above the upper limit temperature for some reason, the heating of the cooking vessel 19 is stopped by stopping energization to the induction heating coils 3 and 4 and stopping the heating operation. It is possible to prevent cooking mistakes due to.

  In the present invention, when setting the upper limit value of the coil current of the induction heating coils 3 and 4, the control circuit 30 is configured to set the upper limit value based on the output that can be set by the operation unit 13. Thus, the programming of the microcomputer constituting the main control circuit 34 can be simplified, heating based on the output set by the user according to the cooking menu can be performed, and cooking failures can be prevented as much as possible. It is possible.

It is a perspective view which shows the Example of this invention. It is a top view which similarly shows the Example of the principal part. It is also a block diagram of a control circuit. It is a side longitudinal cross-sectional view which similarly shows the Example of the principal part. It is a characteristic view which similarly shows operation | movement of a control circuit. It is a characteristic view which similarly shows the relationship between the output of an induction heating coil, and a coil current.

Explanation of symbols

2 Top plate 3 Induction heating coil 4 Induction heating coil 13 Operation part 19 Cooking container 30 Control circuit (control means)
37 Inverter circuit 38 Coil current detection circuit 62 Pan bottom temperature sensor 63 Coil temperature sensor

Claims (7)

A top plate for placing the cooking container, an induction heating coil mounted below the top plate, a temperature sensor for detecting the temperature of the heating coil, an inverter circuit for supplying power to the induction heating coil, and the above This control includes a coil current detection circuit for detecting a current flowing through the induction heating coil, and a control means for controlling the inverter circuit and the like based on the output of the coil current detection circuit and the output of the temperature sensor. A cooking device characterized in that the means is configured to set an upper limit value of a current flowing through the induction heating coil in accordance with a coil temperature detected by the temperature sensor. An operation unit for setting the output of the induction heating coil is provided, and the controller is configured to reduce the current flowing through the induction heating coil when the temperature of the induction heating coil exceeds the set value, and then the temperature of the induction heating coil is set to the set value. 2. The cooking device according to claim 1, wherein when the temperature is further lowered, the current flowing in the induction heating coil is controlled by approaching a set value of the output of the induction heating coil. The cooking device according to claim 2, wherein the control means is configured to control a current flowing through the induction heating coil based on an output that can be set by the operation unit. A top plate for placing the cooking vessel, an induction heating coil mounted below the top plate, a temperature sensor for detecting the temperature of the cooking vessel, an inverter circuit for supplying power to the induction heating coil, and the above In what comprises a coil current detection circuit for detecting the current flowing in the induction heating coil, and a control means for controlling the inverter circuit and the like based on the output of the coil current detection circuit, the output of the temperature sensor, etc. A cooking device characterized in that the control means is configured to set an upper limit value of a current flowing in the induction heating coil in accordance with the temperature of the cooking container detected by the temperature sensor. The operation unit for setting the output of the induction heating coil is provided, and the temperature of the cooking container is lowered from the set value by reducing the current flowing through the induction heating coil when the temperature of the cooking container exceeds the set value. In this case, the cooking device according to claim 4, wherein the current flowing through the induction heating coil is controlled by approaching the set value of the output of the induction heating coil. The cooking device according to claim 5, wherein the control means is configured to control a current flowing through the induction heating coil based on an output that can be set by the operation unit. If the temperature of the cooking vessel does not drop below the set value even when the temperature of the cooking vessel exceeds the set value and the current flowing through the induction heating coil is reduced, the control means is configured to energize the induction heating coil. The cooking device according to claim 2 or 5, wherein the cooking device is configured to stop.

Images