JPS594610B2 - Cooker with heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooking device with a heater that controls the degree of heating (degree of scorching) of food by the rate (concentration) of gas generated from the food being cooked.

In conventional cooking devices with heaters, food is browned by operating the heater to stimulate appetite.

However, it has been extremely difficult to brown foods to an appropriate degree.

In other words, depending on the temperature of the food at the beginning of the heater operation, the amount of food, etc., even if the heater is operated for the same amount of time, the browning will vary, so it is difficult to achieve the appropriate browning by simply setting the heater operation time using a timer. there were.

In order to eliminate this drawback, the present invention detects the amount (concentration) of gas generated from the food being cooked and controls the heating (browning) by the heater, and also reliably detects the amount (concentration) of gas. It was designed to be obtained.

EMBODIMENT OF THE INVENTION Hereinafter, the cooking device with a heater of the present invention will be described in detail with reference to the accompanying drawings showing one embodiment.

FIG. 1 is a simplified configuration diagram of a cooking device with a heater, and shows the cooking chamber 1.
An electromagnetic wave generator 2 such as a magnetron is installed in the center of the upper surface, a heater 3 is installed in the upper part of the cooking chamber 1, and a tray 4 on which food 5 is placed is further provided on the bottom plate of the cooking chamber 1.

A fan 6 is provided at a predetermined position outside the cooking chamber 1, and is configured to supply clean air into the cooking chamber 1 through a ventilation passage 7 and an air outlet 8 provided in the wall of the cooking chamber.

Reference numeral 9 denotes a gas sensor provided at a predetermined position in the cooking chamber 1, and is exposed to air sent out from an exhaust port 10 provided in the wall of the cooking chamber so that its resistance value changes depending on the gas concentration.

Further, as shown in FIG. 2, the gas sensor 9 is connected in series with a dividing resistor 12 between both terminals of a DC power supply 110, and the voltage between the terminals of the dividing resistor 12 is connected to a relay or the like 14 via an amplifier 13. , the relay 14 cuts off the power supply to the heater 3.

The operation of the cooking device with a heater of the present invention having the above structure is as follows.

The food 5 is placed on the toilet 4, the door (not shown) of the cooking chamber 1 is closed, and then the heater 3 is energized to remove the food 5.
Start heating (browning) cooking.

In addition, as shown in FIG. 3, the fan 6 is intermittently operated by intermittently energizing the fan motor,
Blows cool, clean air into the room intermittently.

After the start of cooking, the temperature of the food 5 gradually rises as shown in FIG. 4a, and the concentration of the gas generated also gradually rises.

Therefore, when the fan motor is continuously energized and the fan 6 is operated continuously, the resistance value of the gas sensor a gradually decreases according to the gas concentration.In other words, the voltage across the terminals of the dividing resistor 12 is as shown in FIG. As shown in the figure, the temperature rises in response to the rise in the temperature of the food 5.

However, since the temporal change dv/dt of the voltage between the terminals of the dividing resistor 12 is small, a small voltage fluctuation causes a large time error.

This voltage fluctuation is caused not only by fluctuations in the external power supply but also by noise generated in the internal electric circuit, so accurate control of the degree of heating (browning) of the food cannot be expected.

The reason why the temporal change dv/dt in the voltage between the terminals of the dividing resistor 12 is small is because the continuous operation of the fan 6 causes the concentration of the gas sent out from the exhaust port 10 to be diluted by the outside air.

Therefore, as mentioned above, if the fan motor is intermittently energized to accumulate the gas generated from the food 5 in the cooking chamber 1 when the fan 6 is stopped, and then send it out when the fan 6 is activated next time, the highly concentrated gas will be released. Since it comes into contact with the gas sensor 9, the terminal voltage of the dividing resistor 12 intermittently rises rapidly as shown in FIG. 5, and its temporal change dv/dt becomes large.

The above operation is repeated, and when the fan 6 operates, the exhaust port 1
When the concentration of the gas sent out from zero reaches a predetermined concentration or more, the terminal voltage of the dividing resistor 12 also becomes a predetermined voltage or more, and the relay etc. 14 is activated to cut off the electricity to the heater 3, thereby heating (browning) cooking. finish.

As described above, by intermittently operating the fan 6, the gas generated from the food 5 fills the cooking chamber 1 for a predetermined period of time, and then is sent out from the exhaust port 10, so that the gas sensor 9 receives a high concentration of gas. Since the resistance value becomes extremely low in a short period of time, the voltage between the terminals of the dividing resistor 12 rises rapidly in a short period of time, and the heater 3 can be controlled reliably, and is therefore not affected by fluctuations in the power supply voltage. becomes.

The cooking appliance with heater of the present invention as described above has the following effects.

■ Heating is controlled by measuring the gas generated from the food being cooked, so the food can be browned to the right degree.

■ Since the fan is operated intermittently, the amount of gas generated can be detected using highly concentrated gas, and heating control can be performed reliably without being affected by fluctuations in power supply voltage.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a simplified configuration diagram of a cooking appliance with a heater of the present invention, Fig. 2 is a block diagram of the heater control section, and Fig. 3 shows the time period for energizing the fan motor. Figure 4a is a diagram showing changes in food temperature over time; Figure 5a is a diagram showing changes in voltage between terminals of a dividing resistor over time;
The figure shows the change in voltage between the terminals of a divided resistor over time when detecting gas generated from food in response to intermittent drive of a fan motor. 1... Cooking room, 3... Heater, 4... Tray, 5
...Food, 6.Fan, 9.Gas sensor.

Claims (1)

[Claims] 1. In a heating cooker equipped with a heater, a gas sensor whose electrical constant changes depending on the concentration of gas generated depending on the amount of food heated is set at a predetermined position of the cooker so that it can come into contact with the gas. A cooking appliance with a heater, characterized in that a fan is installed at a predetermined position of the cooking appliance to intermittently blow air into the cooking chamber.