JPS6160328B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention mainly relates to a cooking device for cooking food.

(b) Prior art In general, gas cooking is a gas cooking device in which hot air from a burner such as a gas burner is forcibly supplied to the cooking chamber using a fan or the like, and a part of the hot air in the cooking chamber is discharged to the outside. A temperature sensor is provided at a suitable location in the exhaust passage to relatively detect the temperature inside the cooking chamber. In order to prevent the dough from drying out, it is preferable to stop the fan during low-temperature heating using this cooker, mainly during yeast fermentation. However, when the fan is stopped using the temperature detection structure described above, outside air flows in from the open part of the cooking chamber to the outside, making the temperature distribution in the cooking chamber uneven, and the temperature sensor installed in the exhaust passage also flows in. This creates a problem in that the temperature inside the cooking chamber cannot be accurately detected because it is cooled by outside air.

(C) Object of the Invention The present invention aims to further reduce errors in temperature detection within the cooking chamber and to prevent the surface of the heated object from drying during low-temperature heating.

(d) Structure of the Invention The structure of the present invention is such that a fan is used to forcibly supply combustion hot air from a burner into a cooking chamber that stores objects to be heated, and a temperature sensor is provided in an exhaust passage that exhausts hot air from the cooking chamber. , which is equipped with a control means for heating the inside of the cooking chamber to a desired set temperature by controlling the burner based on the temperature detected by the temperature sensor. The burner burns and the fan is rotated until the temperature reaches the set temperature, which is slightly higher than the set temperature, and after reaching the upper set temperature, the temperature decreases to a predetermined temperature between the lower set temperature and the upper set temperature, which is slightly lower than the set temperature. This system is configured so that the burner is extinguished and the fan is stopped, and then only the fan rotates until the specified temperature is reached and the temperature drops to the lower set temperature.By temporarily stopping the fan, it prevents bread dough from drying out. can.

(e) Embodiment An embodiment of the present invention will first be described based on FIG. A combustion chamber 4 is defined through the bottom plate 3, and a ventilation chamber 6 in which a convection fan 5 is housed is recessed toward the rear of the cooking chamber 2 at the back of the cooking device 2. A turntable device 7 is attached to the bottom of the device 2.

The turntable device 7 includes a drive motor 10 which is disposed in front of the combustion chamber 4 and has a drive shaft 8 facing a through hole 9 formed approximately in the center of the bottom plate 3, and a drive motor 10 which is disposed at the bottom of the cooking chamber 2. It mainly consists of a rotary table 11 which is installed and detachably connected to a drive shaft 8 and is rotationally driven by this, and a mounting plate 12 which is removably placed on the rotary table.

In addition, hot vents (not shown) are opened in both sides of the interior back of the cooking chamber 2, extending upward and downward into the interior of the chamber, and a gas burner 14 is installed near the rear of the combustion chamber 4 with flame vents 13 facing rearward and approximately horizontally. The hot combustion air is guided into the cooking chamber 2. Further, a solenoid valve 16 is installed in the middle of the fuel flow path 15 to the gas burner 14. Reference numeral 17 denotes a rectangular partition plate provided in an opening 18 between the cooking chamber 2 and the ventilation chamber 6, and has an air intake hole 19 formed approximately in the center thereof.

20 is a door that opens and closes the front opening 21 of the cooking chamber 2;
Reference numeral 22 denotes a driving motor for the convection fan 5 disposed outside and rearward of the ventilation chamber 6, 23 denotes a self-cooling fan of this drive motor, and 24 connects to the upper surface of the ventilation chamber 6 and connects it to the cooking chamber 2.
An exhaust passage 25 for discharging hot air inside the exhaust passage outside is a temperature sensor using a thermistor provided in the middle of this exhaust passage.

On the other hand, FIG. 2 shows a part of the electric circuit that serves as the control means, and shows the input ports PA ₀ ~ of the microcomputer 26.
PA ₇ is connected to the temperature sensor 25 and the output of a converter 28 that A/D converts signals from a temperature setting device 27 that sets the heating temperature in the cooking chamber 2. output port
Connected to PB ₁ are light emitting diodes 30, 30 for controlling photothyristors 29, 29 for controlling the rotation of the driving motor 22 of the convection fan 5. The microcomputer 26 is programmed to automatically set an upper set temperature slightly higher than the set temperature and a lower set temperature slightly lower than the set temperature according to the set temperature of the temperature setting device 27. In addition, the photothyristors 29 and 29 are connected to a gate circuit 32 of a triax 31 connected in series to the drive motor 22.
is a door switch 3 that is linked to the opening and closing of the door 20.
3 to a commercial power source 34.

In addition, the other output port PB ₀ of the microcomputer 26 has
It connects the base of a transistor 36 that controls the drive relay 35 of the electromagnetic valve 16, and
The solenoid valve 16 has a relay contact 3 of a driving relay 35.
5' is connected.

When cooking, when an object to be heated is placed on the placing plate 12 and heating is started by setting the temperature setting device 27 to a temperature suitable for cooking, the microcomputer 26 adjusts the output of the temperature sensor 25 and the object to be heated. Compare the output of the temperature setting device 27 and check the temperature inside the cooking chamber 2 (sensor 2
5) is below the lower set temperature determined by the microcomputer, the transistor 36 is turned on by the output signal from the output port PB ₀ , and the relay contact 35' is turned on.
is closed, and at the same time as the electromagnetic valve 16 is opened, the gas burners 14 are ignited and burned by an ignition means (not shown). Also, photothyristor 2 is connected to output port PB ₁ .
9 and 29, a signal for strong rotation of the convection fan 5 (continuously lighting up the light emitting diodes 30 and 30) is outputted to make the convection fan 5 rotate strongly, and the combustion hot air of the gas burners 14 and 14 is delivered to the cooking chamber through a hot air port (not shown). 2 to heat the object to be heated. When the temperature in the cooking chamber 2 reaches the upper set temperature due to the heating, the output signal from the output port _PB0 disappears, the transistor 36 is turned off, and the solenoid valve 16 is closed. On the other hand, since the same output signal is still output from the output port PB ₁ , convection heating by strong rotation of the convection fan 5 continues.

On the other hand, when the temperature setting device 27 is set to low-temperature heating suitable for yeast fermentation (generally about 35°C), the microcomputer 26 automatically switches to the program mode for low-temperature heating, and the output ports PB ₀ , PB The output signal from ₁ is different from that during normal cooking. That is, as shown in Figure 3, the microcomputer 26 compares the output from the temperature sensor 25 and the output from the temperature setting device 27, and determines that the temperature inside the cooking chamber 2 (ambient temperature measured by the temperature sensor 25) is below the lower set temperature ( A point or below), the transistor 36 is turned on by the output signal from the output port PB ₀ as described above, and the gas burner 1 is turned on.
At the same time, the convection fan 5 is strongly rotated by the output signal of the output port PB ₁ to burn the gas burners 14 and 14, and as a result, the temperature inside the cooking chamber 2 rises and exceeds the upper set temperature (point B). For example, when the temperature inside the cooking chamber 2 reaches 37°C, the output signal from the output port PB ₀ disappears, and the transistor 36 is turned off to stop the combustion of the gas burners 14, 14. At the same time, the output of the output port PB ₁ is turned off and the convection fan is turned off. 5
stop rotating.

Furthermore, the ambient temperature of the temperature sensor 25 is
When the temperature drops to a predetermined temperature between the upper set temperature (B point) and lower set temperature (A point) (for example, 33°C, which is the temperature inside the cooking chamber 2 at the D point), the output port PB ₁
The output signal of is switched and, for example, a signal is applied to the light emitting diodes 30, 30 to turn them on at 3 Hz and off at 14 Hz. Therefore, this light emitting diode 30,
Thyristor 31 is turned on and off repeatedly by 30.
As a result, the drive motor 22 is also driven intermittently, and as a result, the convection fan 5 is rotated weakly. Therefore, a portion of the hot air in the cooking chamber 2 is discharged to the outside through the exhaust passage 24 to ensure that the temperature sensor 25 can detect the temperature inside the cooking chamber 2. Also, by detecting the temperature using this, the temperature in the cooking chamber 2
When the internal temperature drops to the same temperature as the above-mentioned point A (point C), the transistor 36 is turned on and the gas burners 14, 14 are fired again, and at the same time,
Switch the output signal of the output port PB ₁ , rotate the convection fan 5 strongly, and repeat the above operation.

(F) Effects of the Invention According to the above configuration of the present invention, drying of the bread dough can be prevented as much as possible without affecting the combustion of the burner and the operation of the temperature sensor during low-temperature cooking such as yeast fermentation. Finishing performance can be improved. Moreover, these can be performed by controlling the rotation of a convection fan, and can be adopted at relatively low cost.

[Brief explanation of the drawing]

FIG. 1 is a side longitudinal sectional view of the present invention, FIG. 2 is a partial electric circuit diagram, and FIG. 3 is a diagram illustrating the operation. 2...Cooking room, 5...Convection fan, 14,14
...Gas burner, 24...Exhaust passage, 25...Temperature sensor, A, C...Lower set temperature, B...Upper set temperature, D...Predetermined temperature.

Claims (1)

[Claims] 1. A fan is used to forcibly supply the combustion hot air of the burner into the cooking chamber where the object to be heated is stored, and a temperature sensor is installed in the exhaust passage that exhausts the hot air in the cooking chamber. In a device equipped with a control means for heating the inside of the cooking chamber to a desired set temperature by controlling Burn the burner and rotate the fan until the set temperature is reached, and after reaching the upper set temperature, turn off the burner while the temperature decreases to a predetermined temperature between the lower set temperature and the upper set temperature, which is slightly lower than the set temperature. A cooking appliance characterized in that the fan is stopped and only the fan is rotated after reaching the predetermined temperature until the temperature drops to the lower set temperature.