JPH08449A - High-frequency thermal rice cooker - Google Patents

Abstract

PURPOSE:To provide a high-frequency thermal rice cooker which achieves higher reliability in the operation of a magnetron along with a simple structure. CONSTITUTION:A magnetron 9 is arranged on the side of a pot 3 to enhance reliability of operation avoiding effect of steam and hot air and a protective frame 6 and a lid bottom are combined to form a waveguide which allows the guiding of microwaves efficiently. This enables the production of a high frequency thermal rice cooker with a simple structure.

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 rice cooker for heating and cooking by using microwaves generated by a magnetron.

[0002]

2. Description of the Related Art A conventional high-frequency heating rice cooker will be described below with reference to FIG. The pot 32 is made of metal and has a main body 31.
Detachable inside. The upper opening of the main body 31 is covered with a lid 33 so as to be openable and closable. A lower portion of the lid 33 is a lower lid 33a made of metal, and a magnetron 34 for generating microwaves is provided in the central portion.

With the above structure, the microwave generated by the magnetron 34 is generated by the metal pot 32 and the metal lower lid 33a.
Is heating the inside of the cavity. In this way, the cooked food contained in the pan 32 is heated and rice cooking proceeds.

[0004]

The high-frequency heating rice cooker having the above-mentioned conventional structure has the following problems. That is, since the magnetron 34 is installed above the pot 32, the magnetron 34 is exposed to steam or hot air generated during rice cooking. That is, for this reason, the magnetron 34 is easily deteriorated, and thermal runaway or the like due to abnormal heating easily occurs. Further, since the load of the magnetron 34, which is relatively heavy, is applied to the lid 33, the opening / closing operation of the lid 33 becomes heavy and the usability is poor.

SUMMARY OF THE INVENTION The present invention solves the problems of the conventional structure, and it is a first object of the present invention to provide a high-frequency heating rice cooker having a simple structure with high operation reliability of the magnetron. I am trying. Further, in relation to the first object, it is a second object to provide a high-frequency heating rice cooker that realizes a function of a stub that reflects and stirs microwaves with a simple structure and does not cause an abnormal temperature rise. There is. A third object is to provide a high-frequency heating rice cooker that can efficiently cool the magnetron. Furthermore, it is the fourth to sixth objects to provide the second to fourth means for achieving the third object. A seventh object is to provide a high-frequency heating rice cooker capable of preventing the temperature rise of the step-up transformer.

[0006]

A first means of the present invention for achieving the first object is to provide a bottomed cylindrical metal pot removably housed in a main body and an upper surface opening of the main body. A lid that covers the openable and closable part, a metal under lid that forms a lower surface of the lid and has a flange portion that performs a choke function at the end, and for discharging vapor provided through the lid. A steam port, a cylindrical metal protective frame having an edge portion that fulfills a choke function at a position corresponding to the flange portion under the lid, and a magnetron for generating microwaves provided on the side surface of the pot, The magnetron is provided with a step-up transformer for supplying a high voltage, and the antenna section of the magnetron is fixed to the protective frame so as to project into the cavity formed by the lid, the pot and the protective frame, and the protective frame and the lid are separated from each other. A high-frequency heating rice cooker that constitutes a waveguide that guides microwaves Is shall.

The second means of the present invention for achieving the second object is a high-frequency heating rice cooker in which the vicinity of the antenna under the lid is formed as a convex portion protruding into the cavity.

A third means of the present invention for attaining the third object is a high-frequency wave in which the upper end of the ventilation part of the cooling fin of the magnetron is located below the upper end of the exhaust port for blowing air of the cooling fan. It is a heating rice cooker.

The fourth means of the present invention for achieving the fourth object is to provide a high-frequency heating rice cooker in which the mounting surface of the magnetron is at least the exhaust port side provided in the main body is horizontal or above the horizontal. To do.

A fifth means of the present invention for attaining the fifth object is such that, when the axis of the antenna of the magnetron is set vertically, the cooling fins are inclined upward with respect to the flow of wind by the cooling fan. It is a high frequency heating rice cooker.

The sixth means of the present invention for achieving the sixth object is high-frequency heating in which the mounting surface of the magnetron is tilted so that the axis of the magnetron antenna is tilted toward the fan side from the vertical direction. It is a rice cooker.

Further, a seventh means of the present invention for achieving the seventh object is a high-frequency heating rice cooker in which a shutoff plate is arranged between the magnetron and the step-up transformer.

[0013]

The first means of the present invention is to arrange the magnetron on the side surface of the pot to avoid the influence of steam and hot air to improve the operation reliability, and the protective frame and under the lid guide the microwave efficiently. The wave tube constitutes a high-frequency heating rice cooker having a simple structure.

The second means of the present invention uses a convex portion projecting downward in the vicinity of the antenna under the lid, and uses this convex portion as a stub for reflecting microwaves, whereby abnormal heating occurs with a simple structure. It does not work as a high frequency heating rice cooker.

According to a third means of the present invention, a cooling fin is provided below the antenna of the magnetron, and the cooling fan is installed at a position where the upper end of the ventilation part of the cooling fin is lower than the upper end of the exhaust port for blowing air of the cooling fan. In this way, the flow of the cooling air becomes smooth and acts as a high-frequency heating rice cooker capable of preventing the accumulation of high-temperature air.

The fourth means of the present invention is that the exhaust port side of the mounting surface of the magnetron is horizontal or above the horizontal,
It serves as a high-frequency heating rice cooker capable of preventing the accumulation of high temperature air due to the exhaust of the cooling air of the magnetron.

According to a fifth aspect of the present invention, when the axis of the antenna of the magnetron is set to be vertical, the cooling fins are provided so as to incline upward with respect to the air flow of the cooling fan, and the cooling air inside the magnetron is provided. It functions as a high-frequency heating rice cooker that smoothes the flow of rice and improves cooling performance.

A sixth means of the present invention is to form a magnetron mounting surface of a protective frame so that an axis of an antenna of a magnetron is inclined from a vertical upper side to a cooling fan side, so that a flow of cooling air in the magnetron is made smooth. In addition, the cooling performance is improved and the performance is stabilized.

In the seventh means of the present invention, a blocking plate provided between the magnetron and the step-up transformer functions to protect the step-up transformer from heat generation of the magnetron and prevent an abnormal temperature rise of the step-up transformer. To do.

[0020]

EXAMPLES Examples of the present invention will be described below.

FIG. 1 is a sectional view of a rice cooker body 1 according to an embodiment of the present invention. Reference numeral 2 denotes a bottomed tubular metal pan 3 which is detachably housed in the rice cooker body 1, and a lid body which covers the upper opening of the rice cooker body 1 so as to be openable and closable. The lower surface of the lid body 2 is a metallic lid lower portion 4 whose edge portion 4b is a flange portion having a choke function. Further, a part of the lower lid 2 is a convex portion 16 that projects into a cavity formed by the lower lid 2 and the metallic pot 3. This convex portion 16
Reflects the microwave generated by the magnetron 9,
It acts as a stub that makes the distribution of microwaves in the cavity uniform. The lid 2 is provided with a steam port 5 which is provided above the pot 3 so as to penetrate the lid 2.
Reference numeral 6 denotes a metal protective frame that supports the pot 3, and includes a flange-shaped edge portion 6b corresponding to the edge portion 4b of the lower lid 4 and a flange portion 6c. The flange portion 6c and the edge portion 4b act as a choke for preventing the microwave generated by the magnetron 9 from leaking out of the cavity together with the flange-shaped edge portion 6b.

A magnetron 9 for generating a microwave is fixed to the side of the pot 3 of the protective frame 6 with the antenna 8 protruding. The magnetron 9 is attached below the protective frame 6 so that the antenna portion 8 projects above the protective frame 6. An electromagnetic induction heating coil 11 that induction-heats the pot 3 is provided below the protective frame 6. Protective frame 6
The outer periphery of is supported by the body 10. A booster transformer 12 for supplying a high voltage to the electromagnetic induction heating coil 11 and the magnetron 9 and a drive circuit 13 for supplying power to the electromagnetic induction heating coil 11 and the booster transformer 12 are provided below the botte.

FIG. 2 is a plan view of the protective frame 6 with the lid 2 removed. The protective frame 6 has a width of the vicinity 6a where the antenna part 8 of the magnetron 9 is provided, which is narrower than that of the rice cooking chamber 14 in which the pot 3 is housed. That is, under the lid 4
A rectangular tubular body is formed together with the vicinity of the antenna portion 4a provided in the rear part of the antenna, and the waveguide portion 15 shown in FIG. 1 is formed to efficiently guide the microwave generated by the magnetron 9 into the cavity. are doing.

FIG. 3 is an external view showing the rear part of the rice cooker, and FIG. 4 shows the magnetron used in this embodiment. 1
Reference numeral 8 is a cooling fan that cools the magnetron 9 and the step-up transformer 12, and blows the outside air supplied from the air supply port 19 provided in the rice cooker body toward the exhaust port 22 provided above the air supply port 19. are doing. At this time, in this embodiment,
The cooling fins 21 provided in the magnetron 9 are provided such that the space upper wall 21a forming the ventilation part of the cooling fins 21 is below the upper end 22a of the exhaust port 22. The mounting surface 20 for mounting on the protection frame 6 of the magnetron 9 is horizontal. Therefore, the vicinity 6a of the protective frame 6 near the antenna portion is also substantially horizontal.

FIG. 5 is a vertical sectional view of the vicinity of the attachment portion of the magnetron 9 of the rice cooker body 1 as seen from the rear.
In this embodiment, the step-up transformer 12 is provided with a blocking plate 24 around the booster transformer 12 to protect it from radiant heat from the magnetron 9.

The operation of this embodiment will be described below. When the pot 3 in which water and rice, which are foods to be cooked, are placed is set in the rice cooker body 1, a power source (not shown) is turned on, and the start switch is turned on, the drive circuit 13 starts driving. By driving the drive circuit 13, the electromagnetic induction heating coil 11 and the step-up transformer 12 start operating. That is, the electromagnetic induction heating coil 11 generates a high-frequency magnetic field to induction-heat the pot 3, and the step-up transformer 12 starts supplying power to the magnetron 9. When the magnetron 9 starts oscillating, microwaves are generated from the antenna section 8. This microwave is efficiently transmitted to the inside of the cavity by the waveguide portion 15 formed by the rear portion 4a of the lower lid 4 and the vicinity of the antenna portion 6a of the protective frame 6. In this way pan 3
Is heated by this microwave and the induction heating by the electromagnetic induction heating coil 11. The food in the pan 3 is cooked by this heating and cooked.

At this time, in this embodiment, as described above, the waveguide portion 15 is formed by the rear portion 4a of the metallic lower lid 4 and the antenna vicinity 6a of the protective frame 6. Therefore, the magnetron 9 can be installed on the side of the pan 3, the magnetron 9 can avoid the influence of steam and hot air, and can generate a stable output.

Secondly, the vicinity of the antenna portion 8 under the lid 4 is formed as a convex portion 16 protruding into the cavity. The convex portion 16 acts as a stub that reflects the microwave generated by the magnetron 9 and uniformizes the microwave distribution in the cavity. That is, in this embodiment, it is not necessary to bother to attach the stub as a separate component. Further, since it is integrally formed with the under-lid 4, it is possible to prevent abnormal heat generation due to lack of joining or the like which occurs when it is formed as a separate component.

Thirdly, the cooling fin 21 provided below the antenna portion 8 of the magnetron 9 is provided on the main body on the opposite side of the cooling fan 18 with the upper end of the ventilation portion sandwiching the magnetron 9 of the cooling fan 18. It is arranged so that it is below the upper end of the exhaust port 22. The cooling air that has passed through the cooling fins 21 of the magnetron 9 is heated to a high temperature by the heat generated by the magnetron, and therefore flows upward. Therefore, the cooling air that has passed through the cooling fins 21 flows toward the exhaust port 22 provided above the cooling air without staying, and it is possible to prevent the formation of a high-temperature air pool.

Fourth, the magnetron 9 mounting surface 20
Is configured such that at least the exhaust port 22 side of the main body is horizontal or above the horizontal, and the cooling air of the magnetron 9 is smoothly discharged from the exhaust port 22 without staying. That is, it is possible to prevent the cooling air of the magnetron 9 having a high temperature from accumulating and, for example, the vicinity of the antenna portion 6a of the protective frame 6 from becoming extremely hot and the body 10 supporting the protective frame 6 from being deformed. It is possible.

Next, the second embodiment of the present invention will be described with reference to FIG.
It will be described based on. In the present embodiment, when the axis of the antenna section 25 of the magnetron 24 is set to be vertical, the cooling fins 26 are arranged in a shape tilted upward.

That is, when the cooling air blown by the cooling fan 27 becomes high in temperature and becomes light due to heat generation of the magnetron 24, the cooling air smoothly flows in the magnetron 24. Therefore, according to the present embodiment, the cooling fin 26 has a high cooling performance for the magnetron 24. That is, the performance of the magnetron 24 is stable.

Next, a third embodiment of the present invention will be described with reference to FIG. In the present embodiment, the magnetron 28 is arranged such that the axis of the antenna is inclined toward the cooling fan 29 side.

In this way, as in the second embodiment, the flow of the cooling air in the magnetron 28 is made smooth to improve the cooling performance and stabilize the performance.

[0035]

The first means of the present invention is to provide a bottomed cylindrical metal pan removably housed in the main body, a lid for opening and closing the upper opening of the main body, and a lower surface of the lid. Corresponding to the bottom of the metal lid that has a flange part that forms a choke function at the end, a steam port that penetrates the lid to discharge steam, and the flange part under the lid A cylindrical metal protective frame with an edge that fulfills the choke function at the position
It is equipped with a magnetron for generating microwaves provided on the side surface of the pot and a step-up transformer for supplying a high voltage to the magnetron, and the antenna part of the magnetron is projected into a cavity formed by the lid underneath, the pot and a protective frame. A high-frequency cooker with a highly reliable magnetron operation and a simple structure, which is fixed to a protective frame with a protective frame and a lid that forms a waveguide that guides microwaves efficiently. It is a thing.

A second means of the present invention is a structure in which the vicinity of the antenna under the lid is a convex portion protruding into the cavity,
It is intended to realize a high-frequency heating rice cooker having a simple function of a stub for reflecting and stirring microwaves and having a configuration in which an abnormal temperature rise does not occur.

According to the third means of the present invention, the upper end of the ventilation part of the cooling fins of the magnetron is arranged so as to be lower than the upper end of the exhaust port for the air blow of the cooling fan. This is to realize a high-frequency heating rice cooker with high cooling performance.

A fourth means of the present invention is that the mounting surface of the magnetron is configured such that at least the exhaust port side provided in the main body is horizontal or above the horizontal, and an air pool of cooling air of the magnetron that has become hot is collected. By preventing this, a high-frequency heating rice cooker with high cooling performance is realized.

The fifth means of the present invention is such that when the antenna axis of the magnetron is set vertically, the cooling fins are arranged so as to incline upward with respect to the flow of wind by the cooling fan. The flow of the cooling air is smoothed to realize a high-frequency heating rice cooker with high cooling performance.

The sixth means of the present invention is such that the mounting surface of the magnetron is tilted so that the axis of the antenna of the magnetron is tilted toward the fan side from the vertical direction, and the flow of cooling air in the magnetron is smoothed. Then, a high-frequency heating rice cooker with high cooling performance is realized.

The seventh means of the present invention is to realize a high-frequency heating rice cooker capable of preventing the temperature rise of the step-up transformer by arranging a blocking plate between the magnetron and the step-up transformer.

[Brief description of drawings]

FIG. 1 is a sectional view of a high frequency heating rice cooker according to a first embodiment of the present invention.

FIG. 2 is a plan view of the high frequency heating rice cooker showing a state in which the lid is removed.

FIG. 3 is a partial cross-sectional external view of the high-frequency heating rice cooker showing the rear side.

[Fig. 4] Same as above, an external view of the magnetron

FIG. 5 is a vertical cross-sectional view of the vicinity of the magnetron mounting portion as seen from the rear.

FIG. 6 is a partial sectional external view of a high-frequency heating rice cooker according to a second embodiment of the present invention.

FIG. 7 is a partial sectional external view of a high-frequency heating rice cooker according to a third embodiment of the present invention.

FIG. 8 is a cross-sectional view of a high-frequency heating rice cooker showing a conventional example.

[Explanation of symbols]

 1 Main Body 2 Lid Body 3 Pan 4 Under Lid 5 Steam Port 6 Protective Frame 8 Antenna Section 9 Magnetron 10 Body 12 Boost Transformer 15 Waveguide Section 16 Convex Section 18 Cooling Fan 19 Air Supply Port 20 Mounting Surface 22 Exhaust Port 21 Cooling Fin 21a Space upper wall 23 Main body 24 Magnetron 25 Antenna part 26 Cooling fin 27 Cooling fan 28 Magnetron 29 Cooling fan 30 Protective frame 31 Blocking plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinichiro Sumiyoshi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Satoshi Nakae 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. ( 72) Inventor Norio Ikeda 1006 Kadoma, Kadoma City, Osaka Prefecture, Matsushita Electric Industrial Co., Ltd. (72) Takashi Oshio, 1006, Kadoma, Kadoma City, Osaka Prefecture (72) Toshiyuki Nakamura, Osaka Prefecture 1006 Kadoma, Kadoma-shi, Matsushita Electric Industrial Co., Ltd.

Claims (7)

[Claims] 1. A bottomed cylindrical metal pot removably housed in a main body, a lid body for opening and closing an upper opening of the main body, and a lid bottom surface to form a choke function at an end portion. Under the lid made of metal having a flange portion to be fulfilled, a steam port for discharging steam provided through the lid body, and an edge portion having a choke function at a position corresponding to the flange portion under the lid. A tubular metal protective frame, a magnetron provided on the side surface of the pot for generating microwaves, and a step-up transformer for supplying a high voltage to the magnetron, and the antenna section of the magnetron under the lid. A high-frequency heating rice cooker that is fixed to the protective frame in a shape protruding from a cavity formed by a pan and a protective frame, and that the protective frame and the bottom of the lid form a waveguide for guiding microwaves. 2. The high frequency heating rice cooker according to claim 1, wherein a portion near the antenna under the lid is a protrusion protruding into the cavity. 3. The high frequency heating rice cooker according to claim 1, wherein the upper end of the ventilation part of the cooling fins of the magnetron is lower than the upper end of the exhaust port of the cooling fan. 4. The high frequency heating rice cooker according to claim 1, wherein at least the exhaust port side provided on the main body of the magnetron mounting surface is horizontal or above the horizontal. 5. The high frequency heating rice cooker according to claim 1, wherein when the axis of the magnetron antenna is set to be vertical, the cooling fins are inclined upward with respect to the flow of the wind by the cooling fan. 6. The high frequency heating rice cooker according to claim 1, wherein the mounting surface of the magnetron is tilted so that the axis of the magnetron antenna is tilted toward the fan side from the vertical direction. 7. The high frequency heating rice cooker according to claim 1, further comprising a blocking plate disposed between the magnetron and the step-up transformer.