JPH11173563A - Microwave oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microwave oven to ensure uniformity of a heating state in the vertical direction of a food and uniformalize the heating state of a food in a flat state. SOLUTION: A microwave oven 1 comprises a heating chamber body 4; a turn table 5 to effect a rotation action and an elevation action; a heating means 6 to heat a food 2 placed on the turn table 5; a detecting means 9 to detect that the food 2 makes access to the heating means 6; and a control means to control a whole action. After the rotation action of the turn table 5 is brought into a stop in a position where the food 2 approaches the heating means 6, the turn table 5 is elevated in a position where a rotation action is left stopped. Or, the turn table 5 is elevated to a position situated facing the heating means 6 in a position where a rotation action is left stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave oven provided with a turntable, and more particularly, to a microwave oven in which control for efficiently heating food is executed.

[0002]

2. Description of the Related Art In recent years, a microwave oven equipped with a turntable has become popular. Among microwave ovens of this kind, as disclosed in Japanese Utility Model Publication No. 4-30800, There is a configuration in which the temperature rise of food is accelerated to shorten the cooking time. That is,
At this time, the microwave oven 31 includes a heating chamber main body 33 provided with an exhaust port 32 as shown in FIG.
Turntable 34 that rotates and turntable 3
A magnetron 36 serving as a heating means for heating the food 35 placed on the top 4, a detection means (not shown) for detecting that the food 35 is close to the power supply port 37 of the magnetron 36, A microcomputer (not shown) which is a control means for controlling the entire operation.
And

In the microwave oven 31, the rotation of the turntable 34 is stopped by detecting that the food 35 placed on the peripheral surface of the turntable 34 has approached the power supply port 37 of the magnetron 36. Accordingly, control for keeping the food 35 close to the power supply port 37 is performed by the microcomputer. That is, in the microwave oven 31, since the food 35 is disposed near the power supply port 37 where the microwave electric field strength is strong, the microwave energy effectively absorbed by the food 35 is increased. The temperature rises faster and the cooking time is shortened. Reference numeral 38 in FIG. 4 denotes a finishing sensor provided in the exhaust port 32 for detecting a finished state of the food 35, and 39 denotes a rotation drive device such as a motor for rotating the turntable 34.

[0004]

However, when the conventional microwave oven 31 is employed, the food 35 is heated in the vertical direction as compared with the case where the food 35 is heated while the turntable 34 is continuously rotated. There is a disadvantage that the uniformity of the state is deteriorated. That is, for example, a glass made of glass filled with 200 cc of water is prepared in place of the food 35, the rotation of the turntable 34 is stopped, and the water is heated for one minute. When a comparative experiment was performed with heating for one minute while operating, the vertical temperature difference of water when the rotation operation was stopped was 3
While the temperature is 5 ° C., the vertical temperature difference when the rotation operation is continued is only 24 ° C.
It is clear that the uniformity of the heating state of the food 35 is better when the rotating operation is continued than when the rotating operation is stopped.

[0005] Such a result is considered to be based on the following reason. That is, as can be seen from FIG. 4, in the microwave oven 31, the power supply port 37 of the magnetron 36 in which the food 35 on the turntable 34 is arranged in proximity is arranged on the bottom surface on one end side of the heating chamber 32. On the other hand, since the exhaust port 32 for discharging steam and the like generated from the food 35 to be heated to the outside of the microwave oven 31 is disposed on the ceiling on the other end side of the heating chamber 32 far from the power supply port 37, It takes time for the vapor generated from the food 35 to reach the finish sensor 38 in the exhaust port 32, and the response speed of the finish sensor 38 is reduced. During this time, the heating state of the food 35 becomes uneven. In addition, since the concentration of steam or the like generated from the food 35 diminishes on the way to the exhaust port 32, the finish sensor 3
8, the detection sensitivity of the food 35 is lost as a result of a delay in detecting the end of cooking by the finish sensor 38.

As one of the methods for solving this kind of inconvenience, though not shown, a power supply port 37 of a magnetron 36 is arranged at a position facing the food 35 on the turntable 34. Can be considered. However, when the food 35 when adopting such a configuration has a flat shape, the food 35 placed on the turntable 34 is located below the power supply port 37, that is, Power supply port 37 with strong microwave electric field strength
In contrast, the food 35 is displaced, so that the microwave energy effectively absorbed by the food 35 is reduced, and the temperature rise of the food 35 is slowed, and the cooking time is extended. It will be.

The present invention has been made in view of the above-mentioned inconveniences, and it is possible to ensure uniformity of the heating state of food in the vertical direction. It is an object of the present invention to provide a microwave oven that can make the heating state uniform.

[0008]

According to a first aspect of the present invention, there is provided a microwave oven having a heating chamber main body, a turntable for rotating and ascending and descending, and a heating means for heating food placed on the turntable. And a detecting means for detecting that the food has approached the heating means, and a control means for controlling the entire operation. The rotation operation is stopped, and the turntable is moved up and down at a position where the rotation operation is stopped.

According to a second aspect of the present invention, there is provided a microwave oven, comprising: a heating chamber main body; a turntable for rotating and elevating; a heating means for heating food placed on the turntable; Detecting means for detecting that the food has approached, and control means for controlling the overall operation, wherein the control means has stopped the rotation operation of the turntable at a position where the food has approached the heating means. Further, it is characterized in that the turntable is raised to a position facing the heating means while the rotation operation is stopped.

A microwave oven according to a third aspect of the present invention is the microwave oven according to the first or second aspect, wherein the exhaust port of the heating chamber main body is mounted on a turntable whose rotation operation has been stopped. It is characterized in that it is open at a position near the food.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view showing a simplified structure of a microwave oven according to an embodiment, FIG. 2 is a plan sectional view thereof, and FIG.
FIG. 1 is an explanatory diagram showing an electric configuration of a microwave oven, and reference numeral 1 in FIGS. 1 and 2 denotes a microwave oven.

The microwave oven 1 according to the present embodiment includes a heating chamber main body 4 provided with an exhaust port 3 for discharging steam and the like generated from the food 2, a turntable 5 that rotates and moves up and down, and a turntable. The magnetron 6 is a heating means for heating the food 2 placed on the magnet 5, a cooling fan 7 for cooling the magnetron 6, and a power supply port 8 from which microwaves generated by the magnetron 6 are emitted. The microwave oven 1 includes a proximity sensor 9 serving as a detection unit that detects that the food 2 has approached, and a microcomputer 10 serving as a control unit that controls the entire operation of the microwave oven 1. The turntable 5 here is supported by a lifting drive device 11 disposed at the bottom of the heating chamber main body 4 so as to be capable of lifting and lowering.
A rotary drive connected to the
Drive device 1 capable of rotating and stopping the motor
The operation of the elevation drive device 11 and the rotation drive device 12 is controlled by the microcomputer 10.

When the turntable 5 is moved up and down, a method as disclosed in Japanese Patent Application Laid-Open No. 8-37087 is to be adopted. As can be seen from FIG. 3, the relay L2 is turned on. Then, the elevating motor 13 is driven. Then, the turntable 5 here is rotated by using the rotary motor 14, and when the relay L3 is turned on, the rotary motor 14 is driven, while when the relay L3 is turned off, the rotary motor is turned. Since the driving of the turntable 14 is stopped, the rotation of the turntable 5 is stopped. When the relays L2 and L3 are both ON, the turntable 5 moves up and down while rotating.

Further, each of the magnetron 6 and the cooling fan 7 constituting the microwave oven 1 according to the present embodiment are disposed on the side of the heating chamber main body 4, and are connected to the magnetron 6 via the waveguide 15. The power supply port 8 that emits microwaves after being coupled is open on the side surface of the heating chamber main body 4. The heating means is not limited to the magnetron 6, but may be an electric heater or the like. Further, a proximity sensor 9 is provided below the power supply port 8 at this time.
It is configured by combining D and a phototransistor. According to the proximity sensor 9, when the food 2 approaches the power supply port 8 that emits microwaves, the irradiation light from the LED shines on the food 2 and is reflected.
In addition, as a result of the reflected light being detected by the phototransistor, it is detected that the food 2 has approached the power supply port 8. The proximity sensor 9 is not necessarily comprised of an LED and a phototransistor. The proximity sensor 9 is disclosed in a distance sensor for measuring a separation distance from the food 2 or disclosed in Japanese Utility Model Publication No. 4-30800. Such as a detection method using light.

Further, the exhaust port 3 provided in the heating chamber main body 4 is located at a position near the food 2 placed on the turntable 5 that has stopped rotating, that is, above the power supply port 8. An opening is provided at the ceiling position of the heating chamber main body 4, and a finish sensor 16 for detecting the finished state of the food 2 via steam or the like generated from the food 2 is provided inside the exhaust port 3. The finish sensor 16
Generally, a sensor having a function of catching and detecting a physical change of the food 2 or a vaporized substance evaporating from the food 2, for example, a humidity sensor, a gas sensor, a temperature sensor, an infrared sensor, or the like is generally used. The microcomputer 10 serving as control means for controlling the overall operation of the microwave oven 1 by controlling the various devices described above in an integrated manner is connected to the power supply port 8 of the magnetron 6 serving as a heating means. Is controlled to stop the rotation operation of the turntable 5 at a position close to and turn the turntable 5 up and down at the position where the rotation operation is stopped.

Next, the microwave oven 1 according to the present embodiment
The operation procedure will be described.

The microwave oven 1 according to the present embodiment has an operation panel 18.
A large number of menu keys 19, such as "milk" and "liquor can", are provided. Thus, the user selects the desired cooking menu by pressing the menu key 19, and then presses the cooking start key 20. And
When the cooking start key 20 is pressed, the relay L3 is turned on and the turntable 5 starts rotating, and a pulse signal for instructing light emission is transmitted from the microcomputer 10 to the LED of the proximity sensor 9. Is done. Therefore, light is emitted from the LED at a timing based on the pulse signal, and when the irradiation light from the LED is reflected by the food 2 close to the power supply port 8, the reflected light is received by the phototransistor. That is, the microcomputer 10 determines that the food 2 has approached the power supply port 8 due to the phototransistor receiving the light.

The microcomputer 10 determines that the food 2 is in a state of being close to the power supply port 8.
Turns off the relay L3 to stop the rotation operation of the turntable 5, and then turns on the relay L2 to start the elevating operation of the turntable 5. Therefore,
The food 2 placed on the turntable 5 repeatedly moves up and down while facing the power supply port 8 while stopped at a position close to the power supply port 8 of the magnetron 6,
The microwave emitted from the power supply port 8 is effectively absorbed by the food 2. That is, at this time, since the food 2 is moved up and down, uneven heating of the food 2 does not occur, and the heating state of the food 2 is sufficiently uniform. Therefore, a glass made of glass filled with 200 cc of water was prepared as a substitute for the food 2, and the water was heated for 1 minute while the turntable 5 was moved up and down. It was confirmed that the water was sufficiently heated by the absorption, and the vertical temperature difference of the water was 26 ° C., and the heating state was much more uniform than before.

In the microwave oven 1 according to the present embodiment, the power supply port 8 of the magnetron 6 is arranged on the side of the heating chamber main body 4 and the food placed on the turntable 5 whose rotation operation is stopped. Since the exhaust port 3 is opened at the ceiling position of the heating chamber main body 4 in the vicinity of the heating chamber 2, it takes a long time for the vapor generated from the food 2 to reach the finish sensor 16 in the exhaust port 3. Thus, the concentration of the vapor or the like generated from the food 2 does not decrease before flowing into the exhaust port 3. Further, when the heating of the food 2 based on the selected cooking menu is completed, the entire operation of the microwave oven 1 is stopped by the microcomputer 10, and the turntable 5 that has been moved up and down moves to the initial position, for example, It returns to the lower end of the vertical movement range and stops.

In the present embodiment, the microcomputer 10 is connected to the power supply port 8 of the magnetron 6.
In this case, the rotation operation of the turntable 5 is stopped at a position where the food 2 is in proximity, and the turntable 5 is moved up and down at a position where the rotation operation is stopped. The magnetron 10 stops the rotation operation of the turntable 5 at the position where the food 2 is close to the power supply port 8 of the magnetron 6 as the heating means, and at the position where the rotation operation is stopped, May be raised to a position facing the power supply port 8 of the magnetron 6. Such a configuration is effective when the food 2 has a flat shape such as a hamburger.

That is, when the user who selects and presses the menu key 19 provided with "Hamburg" on the operation panel 18 and presses the cooking start key 20, the turntable 5 rotates according to the same procedure as described above. The operation will start. When the microcomputer 10 determines that the food 2 has approached the power supply port 8 via the proximity sensor 9, the rotation of the turntable 5 is stopped, and the virtual line in FIG. As illustrated in the example, the turntable 5 in which the rotation operation is stopped is moved to the position where the rotation operation is stopped.
Is moved up to a position facing the power supply port 8, for example, a position at the upper end of the elevating operation range. Therefore, the flat food 2 placed on the turntable 5 effectively absorbs the microwave emitted from the power supply port 8 and is quickly heated.

It is to be noted that the turntable 5 is to be stopped after being moved upward, and the ascending position of the turntable 5 at this time is predetermined based on experimental results and the like. Here, the power supply port 8 of the magnetron 6 is kept at a position where the rotation operation is stopped.
The turntable 5 that has been raised to a position opposite to the above is said to continue to stop.
Can be controlled to move up and down within a range facing the power supply port 8, and such control may be adopted as a matter of course.

[0024]

As described above, according to the first aspect of the present invention,
According to the microwave oven, according to the control means for stopping the rotation operation of the turntable at a position where the food is close to the heating means, and raising and lowering the turntable at a position where the rotation operation is stopped. Therefore, the effect that the uniformity of the heating state in the vertical direction of the food can be improved while realizing the shortening of the cooking time can be obtained.

According to the second aspect of the present invention, the rotation of the turntable is stopped at a position where the food is close to the heating means, and the turntable is stopped at a position where the rotation is stopped. Since the control means for raising the position to the position facing the heating means is provided, even if the food has a flat shape, it is possible to make the heating state uniform while shortening the cooking time without any inconvenience. .

Further, according to the microwave oven according to the third aspect, since the exhaust port is opened at a position near the food placed on the turntable whose rotation operation has been stopped, the steam generated from the food can be obtained. Will quickly flow into the exhaust port, and steam will not dilute,
The effect is obtained that the uniformity of the heating state in the food is not lost.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a simplified structure of a microwave oven according to an embodiment.

FIG. 2 is a plan sectional view thereof.

FIG. 3 is an explanatory diagram showing an electric configuration of a microwave oven.

FIG. 4 is a side sectional view showing a simplified structure of a microwave oven according to a conventional embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Microwave oven 2 Food 4 Heating room main body 5 Turntable 6 Magnetron (heating means) 9 Proximity sensor (detection means) 10 Microcomputer (control means)

Claims (3)

[Claims] 1. A heating chamber body, a turntable that rotates and moves up and down, a heating unit that heats food placed on the turntable, and a detection unit that detects that the food is close to the heating unit. And a control means for controlling the entire operation. The control means stops the rotation of the turntable at a position where the food is close to the heating means, and further controls the position at which the rotation is stopped. A microwave oven for raising and lowering a turntable by using the same. 2. A heating chamber main body, a turntable that rotates and moves up and down, heating means for heating food placed on the turntable, and detection for detecting that the food is close to the heating means. And a control means for controlling the entire operation. The control means stops the rotation of the turntable at a position where the food is close to the heating means, and further controls the position at which the rotation is stopped. A microwave oven for raising the turntable to a position facing the heating means. 3. The microwave oven according to claim 1, wherein the exhaust port of the heating chamber main body is opened at a position near the food placed on the turntable whose rotation operation has been stopped. A microwave oven characterized by: