JP2007141538A - Microwave heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently heat by matching impedance at a microwave generating means 26 side, even in case a load-side impedance might greatly change due to rotation of a rotating waveguide 30. <P>SOLUTION: It is so structured that an impedance at the side of the microwave generating means and that at the load side are matched, by microwave from an opening 41 if tips 31 of the rotating waveguide 30 are headed toward right, and by microwave from the tips 31 if they are headed toward a corner. With this, conditions of matching can be increased during rotation, so that efficient heating is attained through appropriate selection and designing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heating apparatus that heats an object to be heated with microwaves.

  The microwave oven, which is a typical microwave heating device, can directly heat food, which is a typical object to be heated, and is an indispensable device in daily life with the simplicity that does not require the preparation of a pan or pot. ing.

  In particular, the shape of the microwave oven having an oven function and a steam function is such that the size of the space for storing food in the heating chamber through which microwaves propagate is approximately 300 to 400 mm in width and depth dimensions, and the height direction. The size has increased to approximately 200 mm.

  In particular, in recent years, the heating chamber has a wide breadth, with a flat bottom, a width of 400 mm or more, and a relatively larger depth than the depth. Products with shapes have been put into practical use.

  8 and 9 show the configuration of a typical conventional microwave oven. 8 is a cross-sectional view seen from the right, and FIG. 9 is a cross-sectional view seen from the top.

  In the case of a microwave oven with a flat bottom surface, the microwave generated from the magnetron 2 which is a typical microwave generating means is supplied to the bottom surface of the heating chamber 3 in order to supply microwaves from below the mounting table 1 on which food is placed. The main waveguide 5 is guided into the heating chamber 3 through the coupling hole 4 provided in the center, and the rotating waveguide 6 is disposed on the coupling hole 4 and rotates around the coupling hole 4. Uniform heating is achieved by radiating the inside of the heating chamber 3 while changing the direction of the microwave radiated from the tips 7 and 8 of the wave tube 6.

  The rotating waveguide 6 includes a coupling shaft 9 that passes through the coupling hole 4 and couples to the main waveguide 5, and a waveguide portion 10 connected to the coupling shaft 9. The waveguide portion 10 has at least the coupling axis 9. It is the structure which has the bending parts 11 and 12 which bent two sides which oppose on both sides. Since the gap between the bottom surface of the heating chamber 3 is narrowed by the bent portions 11 and 12, the microwave hardly propagates in the direction of the bent portions 11 and 12, and the direction of the open portions 13 and 14 without the bent portions 11 and 12. Will transmit microwaves mainly.

  This is considered to behave like a waveguide in which the top surface of the waveguide 10 and the bottom surface of the heating chamber 3 form an H surface, and the vertical surfaces of the bent portions 11 and 12 form an E surface. Therefore, the microwave travels in the direction of the tips 7 and 8 and is radiated mainly from the open portions 13 and 14 in the horizontal direction. When the distances A and B between the bent portions 11 and 12 are made longer than a half wavelength (about 60 mm for a 2450 MHz microwave), the microwave is transmitted, but the longer distance is transmitted from the A side, that is, from the tip 7. There are a lot of ratios.

  Although the microwave radiated from the rotating waveguide 6 into the heating chamber 3 diffuses, most of it is reflected by the wall surface in front of the tip, and is finally absorbed by the food. At this time, since the heating distribution of the food tends to be strongly heated on the tip 7 side, it is necessary to make it uniform by rotating the rotating waveguide. In general, the coupling shaft 9 can be easily rotated by fitting the drive shaft 16 of the motor 15 into rotation and is called a rotating waveguide.

By the way, here, the rotating waveguide and the rotating antenna are distinguished as follows. As described above, the rotating waveguide forms an H surface and an E surface like a waveguide by a bent portion, and advances microwaves in the direction of the open portion.

  On the other hand, the rotating antenna connected to the coupling shaft is a flat plate without a bent portion, has an opening in the flat plate, has a partially bent portion, but has a configuration that does not face each other, or a so-called waveguide. It is assumed that the H and E planes cannot be formed. As a result, the rotating antenna is not restricted in the direction of microwave travel unlike a waveguide, and therefore radiates upward from anywhere, so unlike a rotating waveguide, radiation in the horizontal direction is reduced. , Will be emitted mainly upward.

  In particular, what is connected to the coupling shaft is a circular flat plate, and there are many configurations with openings, but microwaves are radiated upward from the openings or from the periphery of the circle, and are likely to concentrate on the bottom of food. As a result, the bottom of the food tends to become hot. For example, FIG. 10 is a cross-sectional view as viewed from the right, and FIG. 11 is a cross-sectional view as viewed from above. The rotating antenna 17 is configured to have an opening 19 in a circular flat plate 18.

  As for the rotating waveguide, there are some which improve heating efficiency and make distribution uniform by branching in three or more directions as shown in FIG. FIG. 12 is a cross-sectional view seen from above, and the rotating waveguide 20 is branched in three directions, and each has openings 21, 22, and 23 having different sizes.

Since the branched widths C, D, and E each have a length equal to or longer than a half wavelength, the overall shape of the rotating waveguide 20 increases. It is configured as follows. In this case, even if the rotating waveguide 20 rotates, there is an effect that the coupling between the main waveguide 5 and the rotating waveguide 20 is always maintained in a good state (for example, see Patent Document 1).
JP 2000-353589 A

  However, in the conventional configuration, the rotating antenna tends to cause uneven heating, such that the bottom of the food becomes too hot.

  On the other hand, the rotating waveguide is uniformed by utilizing the reflection on the wall surface, so that the heating unevenness is reduced, but the heating efficiency tends to deteriorate due to the change in the distance to the wall surface. This is because the heating chamber is a substantially rectangular parallelepiped (rectangular in the horizontal direction), and when the rotating waveguide rotates, the part where the tip of the open part faces becomes the center of the wall surface, or the corner where the two wall surfaces are connected Or change from moment to moment.

  After all, when the tip of the open part of the rotating waveguide faces the center of the wall, the distance from the tip to the wall is the shortest, and when facing the corner where the two walls are connected, the distance from the tip to the wall is the longest. Become. Since the change in the distance to the wall leads to a change in the impedance on the load side as viewed from the magnetron, it is considered that the so-called reflection amount of how much microwaves radiated from the magnetron return to the magnetron also changes. For example, if the impedance on the magnetron side and the impedance on the load side match when the distance is the shortest, the amount of reflection is small and efficient heating can be performed.

  However, when the distance is the longest, the impedance on the load side changes greatly, the matching with the impedance on the magnetron side shifts, the reflection amount increases, and the efficiency is considered to deteriorate. Therefore, it is difficult to always perform efficient heating during the rotation of the rotating waveguide.

The present invention solves the above-mentioned conventional problems, and even when the distance to the wall surface is changed by the rotation of the rotating waveguide and the impedance on the load side may change greatly, the impedance on the microwave generating means side An object of the present invention is to provide a microwave heating apparatus that can perform matching and efficient heating.

  In order to solve the above-described conventional problems, a microwave heating apparatus according to the present invention includes a heating chamber for storing an object to be heated, a coupling hole provided in a bottom surface of the heating chamber, and a microwave generation means for generating microwaves. A main waveguide for guiding the microwave generated by the microwave generating means into the heating chamber through the coupling hole, and a rotating waveguide disposed on the coupling hole and rotating around the coupling hole, An opening provided on the upper surface of the rotating waveguide, and the microwave generating means side and the load side impedance are matched in a specific direction of the rotating waveguide by the microwave from the opening It is said.

  As a result, microwaves can be emitted not only from the tip of the rotating waveguide but also from the opening provided on the upper surface of the rotating waveguide, and only by microwaves from the tip of the rotating waveguide as in the past. Not only the impedance on the microwave generating means side and the impedance on the load side are matched, but also the impedance on the microwave generating means side and the impedance on the load side can be matched with the microwave from the opening.

  Therefore, the number of matching conditions can be increased. Therefore, even if the impedance on the load side can change greatly due to the rotation of the rotating waveguide, it can be matched with the impedance on the microwave generating means side by appropriate selection and design. Efficient heating.

  According to the microwave heating apparatus of the present invention, microwaves can be radiated not only from the tip of the rotating waveguide but also from an opening provided on the upper surface of the rotating waveguide. Not only matching the impedance on the microwave generating means side and the impedance on the load side only by the microwave from the tip of the wire, but also matching the impedance on the microwave generating means side and the load side impedance by the microwave from the opening Can do.

  Therefore, the number of matching conditions can be increased. Therefore, even if the impedance on the load side can change greatly due to the rotation of the rotating waveguide, it can be matched with the impedance on the microwave generating means side by appropriate selection and design. Efficient heating.

  According to a first aspect of the present invention, there is provided a microwave heating apparatus comprising: a heating chamber that houses an object to be heated; a coupling hole provided in a bottom surface of the heating chamber; a microwave generating unit that generates a microwave; and the microwave generating unit. A main waveguide that guides the generated microwave into the heating chamber through the coupling hole, a rotating waveguide that is disposed on the coupling hole and rotates around the coupling hole, and an upper surface of the rotating waveguide. The microwave generating means side impedance is matched with the load side impedance in a specific direction of the rotating waveguide by the microwave from the opening.

As a result, microwaves can be emitted not only from the tip of the rotating waveguide but also from the opening provided on the upper surface of the rotating waveguide, and only by microwaves from the tip of the rotating waveguide as in the past. Not only the impedance on the microwave generating means side and the impedance on the load side are matched, but also the impedance on the microwave generating means side and the impedance on the load side can be matched with the microwave from the opening. Therefore, the number of matching conditions can be increased. Therefore, even if the impedance on the load side can change greatly due to the rotation of the rotating waveguide, it can be matched with the impedance on the microwave generating means side by appropriate selection and design. Efficient heating.

  The microwave heating apparatus of the second invention is a structure in which, in the first invention, in particular, in the direction of the rotating waveguide that is not matched by the microwave from the opening, the microwave heating device is matched by the microwave from the tip of the rotating waveguide. It is said.

  As a result, in one specific direction of the rotating waveguide, it is matched by the microwave from the opening, and in the other direction, it is matched by the microwave from the tip. And efficient heating.

  The microwave heating apparatus according to the third invention is the microwave heating device according to the second invention, particularly when the bottom surface of the heating chamber has a substantially rectangular shape and the tip of the rotating waveguide faces the wall surface of the heating chamber. And the microwave from the tip, and when the tip of the rotating waveguide faces the corner of the heating chamber, the other is matched.

  As a result, the distance from the rotating waveguide to the wall can be matched in both the direction of the wall surface where the distance is closest and the direction of the corner where the distance is farthest. They can be matched and can be efficiently heated.

  The microwave heating apparatus according to the fourth invention is the microwave heating apparatus according to the first invention, particularly in the first invention, wherein there are at least two openings, aligned in a specific direction by the microwave from the first opening, and by the microwave from the second opening. It is set as the structure matched in another specific direction.

  As a result, conditions for further matching can be increased, so that more efficient heating can be performed.

  The microwave heating apparatus according to a fifth aspect of the present invention is the microwave heating apparatus according to the fourth aspect, particularly in the direction of the rotating waveguide that is not matched by either the microwave from the first opening or the microwave from the second opening. It is set as the structure matched with the microwave from the front-end | tip of a rotating waveguide.

  As a result, the three openings, the first opening, the second opening, and the tip, are aligned during rotation. Therefore, the alignment can be performed at a rate three times that of the prior art, and more efficient heating can be achieved.

  The microwave heating apparatus according to a sixth aspect of the present invention is the first aspect particularly when the bottom surface of the heating chamber has a substantially rectangular shape and the tip of the rotating waveguide faces the longitudinal wall surface of the heating chamber. When matching is made by any one of the microwave from the opening, the microwave from the second opening, and the microwave from the tip, and the tip of the rotating waveguide faces the wall surface in the short direction of the heating chamber The other one is aligned, and when the tip of the rotating waveguide faces the corner of the heating chamber, the remaining one is aligned.

  As a result, with respect to the distance from the rotating waveguide to the wall surface, the wall surface in the longitudinal direction where the distance is closest, the wall surface direction in the short direction that is a little farther than that, and the corner direction where the distance is the farthest. Since they can be aligned, they can be aligned in most orientations of the rotating waveguide and can be efficiently heated.

  The microwave heating apparatus according to the seventh aspect of the invention is particularly configured in the first to sixth aspects of the invention when the object to be heated is 2 liters of water.

As a result, the impedance on the load side changes depending on the material, shape, and quantity of the object to be heated, so that the matching state also changes. As a result, the high-frequency output can be increased.

  The microwave heating apparatus according to the eighth aspect of the invention is particularly configured in the first to sixth aspects of the invention to be matched when the object to be heated is full of rice.

As a result, the impedance on the load side changes depending on the material, shape, and quantity of the object to be heated, so the matching state also changes, but by matching to the full-frequently used rice in general households, it is efficient in practical menus. Can be heated.
be able to.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 to 3 are configuration diagrams of a microwave oven that is a typical microwave heating apparatus according to the present invention. FIGS. 1 and 2 are cross-sectional views as viewed from above, and FIG. 3 is a cross-sectional view as viewed from the right. .

  The present embodiment is a microwave oven with a flat bottom surface, and microwaves generated from a magnetron 26, which is a typical microwave generating means, for supplying microwaves from below the mounting table 25 on which food is placed. Is provided with a main waveguide 29 that leads into the heating chamber 27 through a coupling hole 28 provided in the bottom surface of the heating chamber 27, and a rotating waveguide 30 that is disposed on the coupling hole 28 and rotates about the coupling hole 28. The heating is made uniform by radiating it into the heating chamber 27 while changing the direction of the microwave radiated from the tips 31 and 32 of the rotating waveguide 30 by rotation.

  The rotating waveguide 30 includes a coupling shaft 33 that passes through the coupling hole 28 and is coupled to the main waveguide 29, and a waveguide portion 34 that is connected to the coupling shaft 33. It is the structure which has the bending parts 35 and 36 which bent the two sides which oppose in between.

  Because the gap between the bottom surface of the heating chamber 27 is narrowed by the bent portions 35 and 36, the microwave is less likely to propagate in the direction of the bent portions 35 and 36, and the direction of the open portions 37 and 38 without the bent portions 35 and 36. Will transmit microwaves mainly. This is considered to behave like a waveguide in which the top surface of the waveguide 34 and the bottom surface of the heating chamber 27 form an H surface, and the vertical surfaces of the bent portions 35 and 36 form an E surface.

  Therefore, the microwave travels in the direction of the tips 31 and 32 and is radiated mainly from the open portions 37 and 38 in the horizontal direction. Although the distances F and G between the bent portions 35 and 36 are both longer than a half wavelength, the F side where the distance is longer, that is, from the tip 31 has a higher ratio of radiating microwaves.

  Although the microwave radiated from the rotating waveguide 30 into the heating chamber 27 diffuses, most of the microwave is reflected by the wall surface in front of the tip and finally absorbed by the food. At this time, since the heating distribution of the food tends to be strongly heated on the tip 31 side, it is necessary to make the heating distribution uniform by rotating the rotating waveguide. In the present embodiment, the drive shaft 40 of the motor 39 is engaged with the coupling shaft 33 and rotated.

  The waveguide portion 34 of the rotating waveguide 30 has an opening 41. In the direction of FIG. 1 (toward the right wall surface of the heating chamber 27) in which the distance from the tip 31 of the rotating waveguide 30 to the wall surface of the heating chamber 27 is shortened by the microwave from the opening 41, an object to be heated (not shown). ) Is 2 liters of water, the impedance on the magnetron 26 side and the impedance on the load (2 liters of water) side are matched.

  Further, by providing the drive shaft 40 (and the coupling shaft 33) at a symmetrical position in the heating chamber, the distance to the wall surface is the same even when facing the left wall surface, so that the alignment can be achieved. Similarly, by providing the drive shaft 40 (and the coupling shaft 33) at symmetrical positions in the heating chamber, the distance is the same even in the forward direction or the rear wall surface, so that the alignment can be achieved. In other words, the orientation of FIG. 1 can be set to 0 degrees, and the alignment can be performed at 0 degrees, 90 degrees, 180 degrees, and 270 degrees.

  At this time, when the distance from the tip 31 of the rotating waveguide 30 to the wall surface of the heating chamber 27 becomes the longest in the direction of FIG. 2 (toward the right rear corner of the heating chamber 27, about 45 degrees), The distance that the wave reaches the wall surface changes drastically, and the impedance on the magnetron 26 side and the impedance on the load (2 liters of water) side do not match.

  Therefore, in such a direction of the rotating waveguide that is not matched by the microwave from the opening 41, a configuration is adopted in which matching is performed by the microwave from the tip 31 of the rotating waveguide.

  As a result, alignment can be achieved even at approximately 45 degrees, approximately 135 degrees, approximately 225 degrees, and approximately 315 degrees which are symmetrical positions.

  As described above, in the present embodiment, the microwave generation means side impedance and the load side impedance are matched in a specific direction of the rotating waveguide 30 by the microwave from the opening 41.

  As a result, microwaves can be radiated not only from the tip 31 of the rotating waveguide 30 but also from the opening 41 provided on the upper surface of the rotating waveguide 31, and from the tip of the rotating waveguide 30 as in the prior art. In addition to matching the impedance on the microwave generating means side and the load side impedance only by the microwaves, the impedance on the microwave generating means side and the load side impedance can also be matched by the microwave from the opening 41. .

  Therefore, the number of matching conditions can be increased. Therefore, even if the impedance on the load side can change greatly due to the rotation of the rotating waveguide, it can be matched with the impedance on the microwave generating means side by appropriate selection and design. Efficient heating. When a rotating body such as a rotating waveguide is used in a heating chamber having a non-circular shape as in this embodiment, it is effective because the distance to the wall surface is not constant.

  In particular, in the direction of the rotating waveguide 30 that is not matched by the microwave from the opening 41, the structure is matched by the microwave from the tip 31 of the rotating waveguide 30. And can be efficiently heated.

  In addition, when the bottom surface of the heating chamber 27 has a substantially rectangular shape and the tip of the rotating waveguide 30 faces the wall surface of the heating chamber 27, the heating chamber 27 is aligned by microwaves from the opening 41, and the tip 31 of the rotating waveguide 30 is When facing the corner of the heating chamber 27, it is configured to match with the microwave from the tip 31. Therefore, with respect to the distance from the rotating waveguide 30 to the wall surface, the direction of the wall surface where the distance is closest and the distance are the longest. Since it can be matched in both the corner direction, it can be matched in most directions of the rotating waveguide 30 and efficient heating can be performed.

  Contrary to the present embodiment, when the tip of the rotating waveguide 30 faces the wall surface of the heating chamber 27, matching is made by microwaves from the tip 31, and the tip 31 of the rotating waveguide 30 is set to the heating chamber. When facing the 27 corners, it may be configured to be matched by the microwave from the opening 41.

Furthermore, since the impedance on the load side changes depending on the material, shape, and quantity of the object to be heated, the matching state also changes. However, if the structure to be matched when the object to be heated is 2 liters of water, the high frequency output of the microwave oven is Since it is measured with 2 liters as a load, the high frequency output can be increased.

  When the bottom shape of the heating chamber is rectangular instead of square, the distance to the wall surface when the tip 31 of the rotating waveguide 30 faces forward (and backward) and the distance to the wall surface when left (and right) are Although different, in such a case, a configuration in which the distance between the two is matched may be adopted. It can be expected that both are consistent to some extent.

(Embodiment 2)
4 to 7 are configuration diagrams of the microwave oven, FIG. 4 is a cross-sectional view seen from the right, and FIGS. 5 to 7 are cross-sectional views seen from the top. In the present embodiment, the waveguide portion 34 of the rotating waveguide 30 has not only the bent portions 42 and 43 bent on opposite sides of the coupling axis 33 but also the bent portion 44 bent on the other side. However, the opening 46 is formed only on the tip 45 side to radiate microwaves. Of course, the distance H is longer than a half wavelength.

  The waveguide 34 of the rotating waveguide 30 has a first opening 47 and a second opening 48. Further, as shown in FIGS. 5 to 7, the bottom surface of the heating chamber 27 has a horizontally long rectangular shape.

  When the object to be heated (not shown) is full of rice, when the tip 45 of the rotating waveguide 30 faces the right wall surface of the heating chamber 27 as shown in FIG. Therefore, the impedance on the magnetron 26 side and the impedance on the load (rice full) side are matched.

  Further, by providing the drive shaft 40 (and the coupling shaft 33) at a symmetrical position in the heating chamber, the distance to the wall surface is the same even when facing the left wall surface, so that the alignment can be achieved. That is, the orientation of FIG. 5 can be set to 0 degree and 180 degrees with an angle of 0 degree.

  Next, when the tip 45 of the rotating waveguide 30 faces the rear wall surface of the heating chamber 27 as shown in FIG. 6, the distance to the wall surface is shorter than that in FIG. The impedance on the magnetron 26 side and the impedance on the load (water 2 liters) side do not match.

  Therefore, in this direction, the impedance on the magnetron 26 side is matched with the impedance on the load (rice full) side by the microwave from the second opening 48. Further, by providing the drive shaft 40 (and the coupling shaft 33) at a symmetrical position in the heating chamber, the distance to the wall surface is the same even when facing forward, so that the alignment can be achieved. That is, it is possible to match at 90 degrees and 270 degrees.

  Further, when the tip 45 of the rotating waveguide 30 faces the right rear corner of the heating chamber 27 as shown in FIG. 7, the distance to the corner is extremely long compared to FIGS. Therefore, the impedance on the magnetron 26 side and the impedance on the load (2 liters of water) side do not match.

  Therefore, in this direction, a configuration is adopted in which matching is performed by microwaves from the tip 45 of the rotating waveguide. As a result, the same applies to other corners. Therefore, it is possible to match even a little less than about 45 degrees, a little over about 135 degrees, a little less than about 225 degrees and a little over about 315 degrees.

  As described above, in the present embodiment, a configuration is adopted in which matching is performed in a specific direction by the microwave from the first opening 47 and matching is performed in another specific direction by the microwave from the second opening 48.

  As a result, the condition for matching can be increased as compared with the case of one opening, so that more efficient heating can be performed.

  In addition, in the direction of the rotating waveguide 30 that is not matched by either the microwave from the first opening 47 or the microwave from the second opening 48, matching is performed by the microwave from the tip 45 of the rotating waveguide 30. The configuration is to let

  As a result, alignment is performed during rotation by the three means of the first opening 47, the second opening 48, and the tip 45, so that the alignment can be performed at a rate three times that of the conventional method, and more efficient heating. Can do.

  In addition, when the bottom surface of the heating chamber has a substantially rectangular shape and the tip 45 of the rotating waveguide 30 faces the right wall surface or the left wall surface (the wall surface in the short direction) of the heating chamber 27, the When the front end 45 of the rotating waveguide 30 faces the rear wall surface or the front surface (longitudinal wall surface) of the heating chamber 27, the rotating waveguide 30 is aligned by microwaves from the second opening 48. When the tip 45 of the 30 faces the corner of the heating chamber 27, the alignment is made by the microwave from the tip 45.

  Thereby, with respect to the distance from the rotating waveguide 30 to the wall surface, all of the wall surface direction in the longitudinal direction where the distance is closest, the wall surface direction in the short direction slightly farther than that, and the corner direction where the distance is the farthest. Can be matched in most directions of the rotating waveguide, and efficient heating can be achieved.

  Note that the present invention is not limited to this embodiment, and the tip 45 of the rotating waveguide 30 faces the wall surface in the short direction, faces the wall surface in the longitudinal direction, or faces the corner. Whether to match the microwaves from the three means of the first opening 47, the second opening 48, and the tip 45 may be freely selected and designed.

  Furthermore, the impedance on the load side changes depending on the material, shape, quantity, etc. of the object to be heated, so the matching state also changes, but if it is configured to match the full object (about 150 g) as the object to be heated, it will be used in general households. Foods that appear to be high in frequency (for example, a glass of drink, a cup of miso soup, a fish fillet, etc.) are almost as light as a full glass of rice, so they can be matched and can be efficiently heated. As a result, the heating time can be shortened, and an energy saving effect can be expected.

  As described above, according to the present invention, the microwave from the opening of the rotating waveguide can be efficiently heated by being matched according to the shape of the heating chamber, so that the cooking utensil using the microwave is used. Such as microwave ovens, microwave ovens, various dielectric heating and thawing devices, semiconductor devices using microwaves, heating devices in industrial fields such as drying devices, ceramics heating, sintering or biochemical reactions, etc. Applicable to usage.

The cross-sectional block diagram in case the rotation waveguide is rightward seeing the microwave heating apparatus of Embodiment 1 of this invention from the top Cross-sectional view of the microwave heating device viewed from above, with the rotating waveguide facing the right rear corner Cross-sectional configuration view of the microwave heating device viewed from the side The cross-sectional block diagram which looked at the microwave heating apparatus of Embodiment 2 of this invention from the side Cross-sectional view of the microwave heating device viewed from above, with the rotating waveguide facing right Cross-sectional view of the microwave heating device as seen from above, with the rotating waveguide facing backward Cross-sectional view of the microwave heating device viewed from above, with the rotating waveguide facing the right rear corner Cross-sectional configuration diagram of a conventional microwave heating device viewed from the side Cross-sectional configuration view of the microwave heating device viewed from above Cross-sectional configuration diagram of another conventional microwave heating device viewed from the side Cross-sectional configuration view of the microwave heating device viewed from above Cross-sectional configuration view of another conventional microwave heating device viewed from above

Explanation of symbols

26 Magnetron (microwave generation means)
27 Heating chamber 28 Coupling hole 29 Main waveguide 30 Rotating waveguide 31, 45 Tip 41 Opening 47 First opening 48 Second opening

Claims (8)

A heating chamber for storing an object to be heated, a coupling hole provided in a bottom surface of the heating chamber, a microwave generating means for generating a microwave, and a microwave generated by the microwave generating means through the coupling hole A main waveguide guided into the heating chamber, a rotating waveguide disposed on the coupling hole and rotating around the coupling hole, and an opening provided on an upper surface of the rotating waveguide; A microwave heating apparatus configured to match the impedance on the microwave generating means side with the impedance on the load side in a specific direction of the rotating waveguide by microwaves. The microwave heating device according to claim 1, wherein in the direction of the rotating waveguide that is not matched by the microwave from the opening, matching is performed by the microwave from the tip of the rotating waveguide. When the bottom surface of the heating chamber has a substantially rectangular shape and the front end of the rotating waveguide faces the wall surface of the heating chamber, the rotating waveguide is aligned with either the microwave from the opening or the microwave from the front end. The microwave heating device according to claim 2, wherein when the tip of the tube faces the corner of the heating chamber, the tube is aligned with the other. The microwave according to claim 1, wherein there are at least two openings, the microwaves from the first opening are aligned in a specific direction, and the microwaves from the second opening are aligned in another specific direction. Wave heating device. A configuration in which matching is performed by the microwave from the tip of the rotating waveguide in the direction of the rotating waveguide that is not matched by either the microwave from the first opening or the microwave from the second opening. 4. The microwave heating apparatus according to 4. When the bottom surface of the heating chamber has a substantially rectangular shape and the tip of the rotating waveguide faces the longitudinal wall surface of the heating chamber, the microwave from the first opening, the microwave from the second opening, and the tip When the tip of the rotating waveguide faces the short-side wall surface of the heating chamber, it is aligned with the other one, and the tip of the rotating waveguide is 6. The microwave heating apparatus according to claim 5, wherein when facing the corner of the heating chamber, the heating chamber is aligned with the remaining one. The microwave heating apparatus according to any one of claims 1 to 6, wherein the object to be heated is configured to be matched when water is 2 liters. The microwave heating apparatus according to any one of claims 1 to 6, wherein the object to be heated is configured to be matched when the rice is full.

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