JPH06101848A - High frequency heating device - Google Patents

Abstract

(57) [Summary] [Purpose] In a high-frequency heating device having a function of thawing food, when the thawing function is used, it is intended to prevent the food that is thawed from being dried by the wind passing through the heating chamber. A damper 14a and a damper 14b which can be freely opened and closed are provided in a ventilation passage 4 for blowing air to a heating chamber 1 to which a variable output high frequency generator 2 is connected or an exhaust passage 5 for exhausting air from the heating chamber 1.
Is provided to close the dampers 14a and 14b to cut off the ventilation to the heating chamber 1 when the output setting of the high frequency generator 2 is the defrosting output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency heating device having a function of thawing foods.

[0002]

2. Description of the Related Art In recent years, the number of frozen foods for home use and business use has increased due to improvements in freezing technology. In response, there are various defrosters that defrost foods.
The high-frequency heating device disclosed in JP-A-58-83133 is one of them.

[0003] As for the defroster utilizing the high frequency heating, a defroster having a so-called cooking function for heating foods to room temperature or higher is generally added at present. Conventionally, when using a cooking function in a high-frequency heating device having this kind of defrosting function, to prevent dew drops on the wall of the heating chamber or fog in the peep window that sees the inside of the heating chamber with cooking steam generated in the heating chamber, There is one in which air is passed through the heating chamber and cooking steam is discharged to the outside of the heating chamber. On the other hand, since air is passed through this heating chamber even when the thawing function is used, the surface of the food is partially dried by the wind that hits the food unevenly during the thawing, so that This is the reason why it is not thawed.
Even if the wind uniformly hits the food, if the surface of the food is dried, the difference in water content between the food inside and the food will cause a difference in appearance, so it is not preferable to apply the wind to the food to be thawed.

A conventional high-frequency heating device will be described below with reference to FIG.
Will be described with reference to. As shown in FIG. 9, the heating chamber 1
A high frequency wave generated by the high frequency wave generator 2 is guided to the waveguide 3. The heating chamber 1 has a door 10 through which foodstuffs 9 can be put in and taken out. A peep window 11 through which the state of the food 9 being cooked or thawed can be confirmed is attached to the door 10. The air 13a taken in by the blower 8 is the blower 13b and the blower 1
Each of the air is divided into 3d and one of the air cools the high frequency generator and is discharged as an exhaust 13c, and the other air passes through the air passage 4 for discharging the steam in the heating chamber 1 and an opening hole in the upper surface of the heating chamber 1 Blow 13e enters the inside of the heating chamber 1 from 6 and is discharged from the heating chamber 1 to the outside through the opening hole 7 on the upper surface of the heating chamber 1 as exhaust 13f through the exhaust passage 5 and exhaust 13g.
Is discharged to the outside of the high frequency heating device. This heating chamber 1
No matter whether the high-frequency heating device operates with the cooking function or the defrosting function, the flow of the air passing through the heating chamber 1 is kept flowing even when the defrosting function is operating.

[0005]

However, when the food 9 is to be thawed in such a conventional structure, the heating chamber 1
Since the blown air 13e passing through the inside hits the food 9, the surface of the food 9 is easily dried. Especially, the time required for thawing is longer than the time required for cooking,
When thawing is done, the time becomes even longer, so that the surface of the food material 9 is continuously blown by the wind, and the effect of drying becomes noticeable. This can be a life-and-death problem since the food 9 is ruined in the case of a business for handling a large or large amount of food 9. There is an idea of covering the food 9 with a cloth or putting it in a container with a lid as a means for preventing the food 9 from drying, but these methods require that the cloth touch the food and be unsanitary. Moreover, putting the food 9 in the container occupies the size of the container,
There is also a drawback that the space of the heating chamber 1 cannot be effectively used for the foodstuff 9, and it is needless to say that it is preferable if the foodstuff 9 can be thawed simply by putting it in the heating chamber 1 as it is.

The present invention solves the above problems, and an object of the present invention is to provide a high-frequency heating device which prevents the food to be thawed from being dried by the air passing through the heating chamber when the thaw function is used.

[0007]

In order to achieve the above object, the present invention as a means for solving the first problem is to blow air into the heating chamber when the high frequency heating device is selected to operate with the defrosting function. An openable and closable damper is provided in the ventilation passage or an exhaust passage for exhausting air from the heating chamber to the outside, and the ventilation of the heating chamber is stopped by blocking the damper.

Further, as a means for solving the second problem, the present invention provides a fan with a rotation speed adjusting tap, and when the high frequency heating device is selected to operate with the defrosting function, the rotation speed switching tap causes the fan to rotate. The number is reduced to almost stop the air blow to the heating chamber.

Further, as a means for solving the third problem, the present invention provides a switch for cutting off the power supply to the blower, and when the high frequency heating device is selected to operate by the defrosting function, the switch is used to stop the blower and heat the blower. It stops the air blow to the room.

[0010]

In the means for solving the first problem of the present invention, when the high-frequency heating device operates by the defrosting function, the ventilation passage for blowing air to the heating chamber or the damper of the exhaust passage for exhausting air from the heating chamber to the outside is provided. Since the ventilation of the heating chamber is shut off, there is almost no wind hitting the food to be thawed, so that the foodstuff is suppressed from being dried and the quality of the thaw is improved.

Further, in the means for solving the second problem, when the high-frequency heating device operates by the defrosting function, the rotation speed adjusting tap provided on the blower is switched to reduce the rotation speed of the blower and blow the air to the heating chamber. Since the amount of food is reduced, the ventilation of the heating chamber is suppressed, and the amount of food to be thawed is prevented from being dried by that much, thus improving the quality of thaw.

Further, in the means for solving the third problem,
When the high-frequency heating device operates with the thawing function, the switch that shuts off the power to the blower is turned off to stop the blower and stop blowing air to the heating chamber, so there is almost no wind that hits the food to be thawed, and the food to be thawed is dried by that amount. Will be suppressed and the quality of thawing will be improved.

[0013]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIG.
It will be described with reference to FIGS. The same numbers are used for the same components as those described in the conventional example.

As shown in FIG. 1, there is a door 10 in the heating chamber 1, and the door 9 is opened to put the foodstuff 9 therein. The door 10 is closed and the high frequency generated by the high frequency generator 2 is introduced into the heating chamber 1 by the waveguide 3. The food 9 is dielectrically heated by the high frequency. As shown in FIG. 5, when the food 9 at room temperature is heated and cooked, it is heated at almost all outputs of high frequency in a relatively short time from room temperature to about 70 to 100 ° C. Go up and food ingredients 9
On the other hand, since thawing to raise the temperature of the frozen foodstuff 9 to a temperature close to room temperature is performed using almost low high frequency output, when cooking the foodstuff 9 at room temperature from the start to the end of thawing In comparison, the time is longer and the food material 9 does not reach a temperature at which steam is emitted. Therefore, when the frozen food 9 is thawed, there is no concern about dew drops inside the heating chamber 1, and the evacuation of the heating chamber 1 for that is unnecessary. The high frequency heating device may heat and cook the foodstuff 9 at room temperature, and in order to discharge the steam accompanying cooking, the blower path 4 that connects the blower 8 and the heating chamber 1 and the exhaust that connects the heating chamber 1 and the outside of the high frequency heating device. A path 5 is provided. When thawing the frozen food 9, the exhaust of the heating chamber 1 is unnecessary as described above,
In order to prevent the food material 9 from drying, a damper 14a is provided in the air passage 4 or a damper 14b is provided in the exhaust passage 5 to shut off the ventilation of the heating chamber 1. The wind from the blower 8 at this time is cut off into the heating chamber 1 by the damper 14a.
3b only cools the high frequency generator 2 and is discharged as exhaust 13c.

FIG. 2 is an enlarged sectional view taken along the line AA 'in FIG. 1. The operation of the damper section provided in the air passage 4 will be described with reference to FIG. Solenoid 15a
The damper 14a attached to the movable part 19a of the solenoid is movable around the rotary shaft 18a.
When electricity is supplied to 5a, the movable portion 19a is pulled into the solenoid 15a, the damper 14a also moves simultaneously, and the passage of the ventilation passage 4 is blocked. When the energization of the solenoid 15a is stopped, the damper 14a is moved by the return spring 16a, the passage of the ventilation passage 4 is opened, and the air is blown into the heating chamber 1. The damper 14b provided in the exhaust passage 5 through which the exhaust gas from the heating chamber 1 is passed has the same operation as that of the damper 14a described above, and a description thereof will be omitted. By the way, in each part of the exhaust passage 5 side, 15
b is a solenoid, 16b is a return spring, 18b is a rotary shaft,
19b is a movable part.

FIG. 3 is an external perspective view of the control panel 12 as seen from the front of the high-frequency heating device. Select "Cook" or "Thaw" on the mode switch 17 to "Thaw"
Choose. Next, the heating time is set with the timer dial 20, and the start button 21 is pressed to start thawing.

FIG. 4 is a typical electric circuit diagram of the high frequency heating apparatus. When the mode changeover switch 17 of the control panel 12 is set to "defrost", the electronic circuit 22 works in conjunction with it to operate the solenoids 15a and 15b. When the coil is energized, the damper 14a moves and the blower passage 4 is cut off, or the damper 14b moves and the exhaust passage 5 is cut off. When the heating time is set with the timer dial 20 and the start button 21 is pressed, the contact of the start relay 24 is turned on and the coil 25 is energized, and the blower 8 starts to rotate.
Further, when the contact of the intermittent relay 23 is also turned on, the high frequency generator 2 oscillates and the food 9 is irradiated with high frequency radio waves. The on-off relay 23 is an on-off relay corresponding to the magnitude of the output of the food 9 to be heated, and an on-off signal corresponding to the heating pattern is output from the electronic circuit 22, and the high-frequency generator 2 is turned on accordingly. Emit high frequency radio waves. The magnitude of the high frequency output required for defrosting is created by controlling the intermittent duty of the intermittent relay 23. When the heating time ends, the electronic circuit 22 starts the start relay 2
4. A signal for disconnecting the power supply to the intermittent relay 23 is output, the contacts of each relay are opened, and the blower 8 and the high frequency generator 2 stop operating and the thawing ends. By the way, when the mode changeover switch 17 is set to cooking, the coils of the solenoids 15a and 15b are not energized, and the blower 4 and the exhaust passage 5
The dampers 14a, 14b are opened and the heating chamber 1 is ventilated.

In the above structure, the control panel 1
The solenoid 15 is interlocked with the selection of "thaw" by selecting "cooking" and "thaw" with the mode changeover switch 17 of 2.
Since the a and 15b work to close the dampers 14a and 14b to eliminate the ventilation of the heating chamber 1, the foodstuff 9 by the wind at the time of thawing
Can be prevented from drying and good thawing can be realized.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 6 and 7. In FIG. 6, the first
1 is that the solenoids 15a and 15b are eliminated, and instead the coil 25a of the blower 8a is provided with a switching tap for varying the rotational speed. Solenoids 15a, 15b for driving dampers 14a, 14b for blocking the passage of the passage 5
Although there is no such thing as the so-called conventional structure shown in FIG. 9, the blower 8a has the coil 2 so that the rotation speed can be changed as described above.
5a is provided with a switching tap. This is the first
This embodiment is a simple and low-priced embodiment against the fact that the means for cutting off the ventilation of the heating chamber 1 becomes expensive in terms of structure such as a damper and a solenoid in terms of cost. When the mode changeover switch 17 of the control panel 12 of FIG. 3 is set to "thaw", the tap of the coil 25a of the blower 8a is switched from b to a through an electronic circuit so as to reduce the rotation speed from the normal state in synchronization with it. . FIG. 7 is a diagram showing an example of the intermittent duty pattern of the high-frequency generator 2 during thawing and heating, and the corresponding output of the high-frequency generator 2 and the anode temperature. From the start of decompression to (a), all outputs are output from (a) to (b), and (b)
After that, the output is further reduced. The output is gradually reduced, and the anode temperature of the high frequency generator 2 also decreases accordingly. Therefore, the rotation speed of the blower 8a may be output from the electronic circuit at an appropriate timing to switch the tap of the coil 25a. According to this configuration, ventilation of the heating chamber 1 is not completely eliminated as in the first embodiment, but there is no problem in thawing and the high-frequency generator 2 can be cooled without any problem. Can be realized at low cost.

(Embodiment 3) Next, a third embodiment of the present invention will be described with reference to FIG. 8 is different from the second embodiment in that instead of the fan 8a with the rotation speed switching tap, a switch 26 is inserted in series with the coil 25 of the fan 8 without the switching tap, which is the same as in FIG. 4 of the first embodiment. It is that. When the mode changeover switch 17 shown in FIG. 3 is set to "defrost", the switch 26 is interlocked with the mode changeover switch 17 so as to be changed from an on state to an off state through an electronic circuit. The timing at which the switch 26 is turned off is the same as that described with reference to FIG. 6 of the second embodiment, and here, when the output of the high frequency generator 2 is lowered to such an extent that the anode temperature of the high frequency generator 2 does not interfere with natural cooling. is there. According to this configuration, ventilation of the heating chamber 1 is not completely eliminated as in the second embodiment, but a ventilation state that does not substantially affect thawing can be realized at a simpler and lower cost.

[0021]

As is apparent from the above description, the high frequency heating apparatus of the present invention has the following effects.

(1) If the food is thawed with a high-frequency heating device, it can be thawed quickly, but the surface of the food material is dry and the appearance is poor. There is also a method of covering the food material with a cloth, but it is troublesome and the food temperature is high. It tends to be unsanitary because it does not occur, or the size of foodstuffs is restricted to the container if put in a container A damper is added to the ventilation path or exhaust path that vents to the heating chamber of the high frequency heating device, and the above-mentioned at the time of thawing Since the ventilation is controlled so that the food is simply put in the heating chamber, the drying can be prevented, and high-quality thawing can be realized.

(2) Since the means for shutting off the ventilation of the heating chamber by using the damper described above is structurally complicated and the cost is high, there is some ventilation to the heating chamber. If the means for reducing the number of rotations is switched by tapping the coil of the blower, it is possible to realize high-quality thawing by a high-frequency heating device which is cheaper than that by the means for blocking ventilation.

(3) If the means for reducing ventilation to the heating chamber is not a coil switching tap of the blower but a switch connected in series to the coil of the blower to stop the blower,
Furthermore, high-quality thawing can be realized by an inexpensive high-frequency heating device.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a high-frequency heating device of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along line AA ′ of the above.

FIG. 3 is an external perspective view of the control panel of the above.

FIG. 4 is an electric circuit diagram of the above.

FIG. 5 is a diagram showing a rise in temperature of each food material due to heating.

FIG. 6 is an electric circuit diagram showing a second embodiment of the high-frequency heating device of the present invention.

FIG. 7 is a graph showing changes in high-frequency average output and anode temperature of a high-frequency generator during thawing.

FIG. 8 is an electric circuit diagram showing a third embodiment of the high-frequency heating device of the present invention.

FIG. 9 is a perspective view of a conventional high-frequency heating device.

[Explanation of symbols]

 1 Heating chamber 2 High frequency generator 4 Blower 5 Exhaust 8 Blower 14a, 14b Damper

Claims (3)

[Claims] 1. A heating chamber, a variable-frequency high-frequency generator coupled to the heating chamber, and a blower for blowing air into the heating chamber.
An openable damper that blocks ventilation is provided in a ventilation path connecting the blower and the heating chamber or an exhaust path that exhausts air from the heating chamber to the outside, and the high-frequency generator is set to a high-frequency output setting to defrost output. By providing a means to replace,
A high-frequency heating device configured to close the damper when the output setting for switching the high-frequency output is defrosting output. 2. A heating chamber, a high-frequency generator with a variable output coupled to the heating chamber, and a blower for blowing air into the heating chamber.
The blower is provided with rotation speed switching means, and the high frequency generator is provided with means for switching the high frequency output setting to the defrosting output, and when the output setting for switching the high frequency output is defrosting output, the rotation frequency of the blower is switched. A high-frequency heating device in which the switching of the means is switched to the side where the rotation speed decreases. 3. A heating chamber, a variable-frequency high-frequency generator connected to the heating chamber, and a blower for blowing air to the heating chamber.
A switch is provided in series with the blower, and a means for switching the high-frequency output setting to the defrosting output is provided in the high-frequency generator, and the blower is turned off by turning off the switch when the output setting for switching the high-frequency output is the defrosting output. High-frequency heating device configured to cut off the power to the device.