JP2011153751A - Microwave cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microwave cooker for controlling heating a heated object from upper and lower surfaces, even if a heating tray with the heated object is set on a tray receiving part. <P>SOLUTION: The microwave cooker is provided with resin holders (locating spacers) at right and left ends of a heating tray 402, in a front-rear direction, from a front side opening to an inner side of a heating chamber 34. The microwave cooker is configured such that a controller 411 changes a direction of opening part in accordance with an output signal from an operation part and controls a microwave supply amount from upper and lower surfaces of the heating tray 402 supported by the tray receiving part 404. The configuration of the microwave heating cooker is made so that the microwave supply amount to the upper surface of the heating tray 402 at an early phase of cooking operation is greater than an amount after the early phase. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a microwave heating cooker that dielectrically heats an object to be heated.

  The microwave oven, which is a typical microwave heating cooker, can directly heat food that is to be heated, making it an indispensable cooking tool in daily life because it does not require the preparation of a pot or pot. Yes. In recent years, the heating room has a wide horizontal space and has improved convenience by flattening the bottom of the heating room space for storing food, making the width dimension 400mm or more, and making it relatively larger than the depth dimension, and arranging multiple dishes. Products that have

  In addition, with the multi-functionalization of microwave ovens, there are those equipped with the so-called “warming menu” (microwave heating that cooks food by radiating microwaves to food) and “thaw menu” Has appeared on the market. The “thawing menu” is a menu for thawing frozen foods by continuously or intermittently radiating and heating microwaves, heating frozen foods with superheated steam and thawing them, or a combination of these. That is.

  Conventionally, as shown in FIG. 10, this type of microwave heating cooker 300 includes a waveguide 303 that transmits a microwave radiated from a magnetron 302 that is a typical microwave generation unit, a heating chamber 301, The mounting table 306 is fixed in the heating chamber 301 for mounting a food (not shown) as an object to be heated, and is made of a low-loss dielectric material such as ceramic or glass so that microwaves can be easily transmitted. And a power feeding unit (antenna space) 310 formed below the mounting table 306 in the heating chamber 301, and a microwave feeding in the waveguide 303 into the heating chamber 301. 310, a rotating antenna 305 attached near the center of the heating chamber 301, a motor 304 as a typical driving means capable of rotationally driving the rotating antenna 305, and heating. A heating pan 308 which is installed depending on the application within 301, a disc receiving portion 307 which supports the heating pan 308, but with a heater 309 for performing the electric heating.

  When a warming menu for directly heating an object to be heated by microwave heating is selected and executed, the microwave heating process is executed with foods or the like placed on the mounting table 306. The microwave radiated from the magnetron 302 is once absorbed by the rotating antenna 305 through the waveguide 303, and the microwave is radiated from the upper surface of the radiating portion of the rotating antenna 305 toward the heating chamber 301. At this time, normally, in order to uniformly stir the microwaves in the heating chamber 301, the rotating antenna 305 radiates the microwaves while rotating at a constant speed (see, for example, Patent Document 1).

  In addition, when a thawing menu for heating frozen food that is an object to be heated is selected and executed by microwave heating, the frozen food is placed on a heat-resistant tray or flat plate and placed on the mounting table 306. Then, the menu is selected and the operation of the microwave heating cooker is started. When the object to be heated reaches a predetermined temperature or when the operation is performed for a set time, the operation is terminated (for example, see Patent Document 2). ).

  In addition, in the grill menu for cooking in a direct-fired style, food (for example, chicken, meat, fish, etc.) is placed on the heating dish 308 placed in the dish receiving unit 307. In this state, the surface portion of the food is heated by the heater 309 located above the food. On the other hand, the back surface portion of the food is heat-treated by the heating dish 308 heated by the microwave.

JP 2004-071216 A JP 09-229372 A

  However, the conventional microwave heating cooker as described in the above-mentioned patent document, when using frozen food for cooking, after executing the above-mentioned thawing menu, further setting the menu again and executing the warming menu Therefore, after the thawing is completed, it is necessary to reset the heating dish containing the thawed food to a predetermined dish receiving portion and execute the warming menu, which is troublesome.

  Therefore, it is conceivable that the heating dish 308 containing frozen food is supported from the beginning by a predetermined dish receiving unit 307 and the process from thaw cooking to warm cooking is executed. However, the rotating antenna 305 radiates microwaves uniformly into the heating chamber 301 while rotating at a constant speed. However, when the heating dish 308 is supported by the dish receiver 307, the peripheral edge of the heating dish 308, the inner wall of the heating chamber 301, and the like. There is almost no gap between them, and the microwave on one surface of the heating plate 308 (the surface on the power feeding unit 310 side) is unlikely to wrap around the other surface. Therefore, when the power feeding unit 310 is provided below the heating chamber 301, the upper surface of the heating pan 308 is insufficient, and when the power feeding unit 310 is provided above the heating chamber 301, the heating pan 308 is insufficiently heated and the cooking time is long. There was a problem that the quality of cooking would be reduced.

  The present invention solves the above-mentioned conventional problems, and a microwave heating cooker that can control heating of an object to be heated from both the upper and lower sides even when a heating dish on which the object to be heated is placed is set in a tray receiving unit. The purpose is to provide.

  In order to obtain the desired cooking performance, it is necessary to set the heating dish 308 at a predetermined position, but it is difficult to set the heating dish 308 at a predetermined position. This is because in order to supply microwaves fed from below the heating pan 308 to the upper side of the heating pan 308 and to prevent the occurrence of sparks between the heating pan 308 and the inner wall of the heating chamber 301, It was necessary to provide a gap between the peripheral edge of the heating dish 308 and the inner wall of the heating chamber 301, and there was a problem that the setting position of the heating dish 308 was shifted in the front-rear and left-right directions.

  The present invention solves the above-described conventional problems, and provides a microwave heating cooker that can supply microwaves to the upper and lower surfaces of the heating dish while reducing the displacement when the heating dish is set in the heating chamber. The purpose is to do.

In order to solve the above-described conventional problems, a microwave heating cooker according to the present invention includes a heating chamber in which a door is provided in a front opening to store an object to be heated, and a microwave permeable plate that constitutes a bottom surface of the heating chamber. A table, a metal heating dish that is detachably attached to the heating chamber and places an object to be heated, a tray receiving unit that supports the heating dish provided in a plurality of stages in the heating chamber, and generates microwaves Means, a waveguide for transmitting the microwave from the microwave generating means, a rotating waveguide for radiating the microwave from the open part of the waveguide to the heating chamber, and rotating the rotating waveguide Based on an output signal from the operating means, a driving means for driving, a power feeding part formed below the mounting table and provided with the rotating waveguide, an operating part for selecting a cooking menu of an object to be heated, and the operation part Control means for controlling the drive means, The means is configured to change the direction of the opening according to an output signal from the operation unit, and to control a microwave supply amount from the upper and lower surfaces of the heating dish supported by the dish receiving unit. In this configuration, the amount of microwaves supplied to the upper surface of the dish is controlled so that the initial value of the cooking operation is greater than the initial value.

  As a result, the operation of the rotating waveguide is controlled in accordance with the contents of the selected cooking menu, so that the microwave concentrates on the object to be heated when the warm menu is selected, and the frozen food efficiently rises when the thaw menu is selected. Since it can be controlled to warm, even when the heating pan on which the object to be heated is placed is set in the tray receiver, the heating of the object to be heated can be controlled from both the upper and lower sides, and it is suitable for the type of object to be heated. A desired cooking finish can be obtained and heating efficiency can be improved.

  The microwave heating cooker of the present invention can heat a heated object from both the upper and lower surfaces even when the heated dish on which the heated object is placed is supported by the tray receiver, and can cook with good quality in a short time.

Front sectional view of the microwave oven (microwave heating cooker) according to Embodiment 1 of the present invention. Side surface sectional drawing of the state which set the cooking pan in the heating chamber in order to show the positional relationship of the holder of the microwave oven of Embodiment 1 of this invention The block diagram which shows the side surface cross-section structure in A-A 'in FIG. 1 of the microwave oven of Embodiment 1 of this invention 1 is a cross-sectional view taken along line B-B ′ in FIG. 1 for explaining the direction of the rotating waveguide when the heating pan is supported by the upper, middle, and lower tray receivers. 1 is a cross-sectional view taken along the line C-C ′ in FIG. 1 for explaining the origin detection mechanism of the rotating waveguide. Schematic configuration diagram of the control means 411 Operation flowchart of microwave oven of the first embodiment Schematic configuration diagram of temperature detection means Plan sectional drawing when there are two rotating waveguides which are modifications of the microwave oven of this Embodiment 1. Schematic configuration diagram of a conventional microwave oven

  1st invention provides the heating chamber which provides a door in a front opening, and accommodates a to-be-heated object, the microwave-permeable mounting base which comprises the bottom face of the said heating chamber, and is attached to the said heating chamber so that attachment or detachment is possible. A metal heating pan on which an object is placed, a plurality of stages in the vertical direction in the heating chamber, a tray receiving portion that supports the heating tray, a microwave generation means, and a microwave transmission from the microwave generation means A waveguide, a rotating waveguide that radiates the microwave from the open portion of the waveguide to the heating chamber, driving means for rotationally driving the rotating waveguide, and a lower part than the mounting table. A power supply unit provided with the rotating waveguide; an operation unit that selects a cooking menu for an object to be heated; and a control unit that controls the drive unit based on an output signal from the operation unit, the heating dish The front opening of the heating chamber is While providing a positioning spacer made of resin over the inner surface of the heating chamber, the control means changes the direction of the opening portion according to an output signal from the operation portion, and is supported by the dish receiving portion. It is configured to control the amount of microwave supply from the upper and lower surfaces of the heating dish, and is configured to control the amount of microwave supply to the upper surface of the heating dish so that the initial stage of the cooking operation is greater than the initial stage, By controlling the microwave heating power so that the initial stage of the cooking operation is stronger than after the initial stage, the heated object can be moved up and down even when the heated dish on which the heated object is placed is set in the dish receiving portion. It can be heated from both sides and can be cooked in good quality and in a short time.

When the heating dish is set in the heating chamber, the microwave supply to the upper and lower surfaces of the heating dish is reduced through the resin-made positioning spacers or through the gaps generated by the positioning spacers while reducing the positional deviation. Can be done.

  In particular, the second invention further comprises the first invention further comprising a dish receiving portion provided in the heating chamber for supporting the heating dish, and a microwave absorber provided on the lower surface of the heating dish, thereby absorbing the microwave. It is possible to efficiently raise the temperature of the heating dish by concentrating microwaves on the body.

  According to a third invention, in the first or second invention, there is provided temperature detecting means for detecting a temperature of an object to be heated or a heating dish in the heating chamber, and the control means is configured to perform rotation guidance based on a detection result of the temperature detecting means. By controlling the operation of the wave tube, even when the thawing menu is selected, the rotating waveguide is rotated at a constant speed at the initial stage of heating, and a difference in the temperature distribution of the heating chamber or pan begins to occur. In this case, the rotation waveguide can be shifted to the operation control based on the position information stored in the control means.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the control unit can control the driving unit so that the open portion of the rotating waveguide is stopped at a position facing a predetermined direction. The heating efficiency of the dish can be improved.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the driving unit is controlled by stopping the driving unit so that the opening of the rotating waveguide is stopped at a position facing the front opening direction of the heating chamber. Thus, the rotating waveguide can be controlled to stop near the front surface of the heating chamber, and the heating efficiency of the heating dish can be improved.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the control unit controls the driving unit so that the open portion of the rotating waveguide swings in the vicinity of the position in the predetermined direction. By continuing to stop the rotating waveguide during the microwave radiation, the microwave is prevented from being excessively concentrated on a part of the rotating waveguide to prevent overheating. Moving about ± 5 degrees around the target angle has little effect on the heating efficiency of the heating pan, but on the other hand, a sufficient effect can be obtained for preventing excessive rise of the rotating waveguide component.

  According to a seventh invention, in any one of the first to fifth inventions, the control means rotates the rotating waveguide during heating by the microwave, and the open portion of the rotating waveguide is in the vicinity of a predetermined position. By controlling the driving means so as to decelerate at, the rotating waveguide continues to stop during the microwave radiation, so that the microwave is excessively concentrated on a part of the rotating waveguide, thereby overheating. Can be prevented.

  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)
FIG. 1 is a front sectional view of the microwave heating cooker according to the first embodiment of the present invention, and FIG. 2 shows a cooking dish for showing the positional relationship of the holder of the microwave oven according to the first embodiment of the present invention. FIG. 3 is a block diagram showing a side cross-sectional configuration of the microwave oven (AA ′ cross-sectional view in FIG. 1), and FIG. 4 is an upper, middle, and lower stage of the heating pan. FIG. 5 is a diagram for explaining the orientation of the rotating waveguide when supported by each dish receiving portion (cross-sectional view along BB ′ in FIG. 1), and FIG. 5 is a diagram for explaining the origin detection mechanism of the rotating waveguide (FIG. 1). 6 is a schematic configuration diagram of the control unit 411, FIG. 7 is an operation flowchart of the microwave oven of the first embodiment, FIG. 8 is a schematic configuration diagram of the temperature detection unit, and FIG. The modification of the microwave oven of this Embodiment 1 (example with two rotating waveguides) is shown.

In the figure, a microwave oven 31 includes a main body 31a and a door 31b. Body 31
a is connected to a heating chamber 34 for storing a heated object such as food, a magnetron 32 for irradiating a microwave for cooking the heated object, and a magnetron 32 for guiding the microwave into the heating chamber 34. The waveguide 33 is built in. A front opening 38 is formed in the front surface of the heating chamber 34.

  The door 31b is attached to the main body 31a, and covers the front opening 38 formed in the heating chamber 34 so as to be freely opened and closed. The door 31b may be attached to the main body 31a via a hinge, or may be attached to the main body 31a as a sliding type like a sliding door. Moreover, when the microwave oven 31 is a built-in type, you may attach to the main body 31a in the form which pulls out the door 31b. Furthermore, when attaching via a hinge, you may attach in any direction of the main body 31a.

  The door 31b includes a metal plate 60, an inner glass 61 and an outer glass 62 that sandwich the metal plate 60 in the front-rear direction, and a choke cover (not shown) that covers the outer periphery of the metal plate 60. A plurality of through holes are formed at positions facing the front opening 38 of the metal plate 60 so that the inside of the heating chamber 34 can be seen. A choke structure 63 is formed on the outer periphery of the metal plate 60. Here, a case where the choke structure 63 is formed by bending a plurality of metal plates 60 is shown as an example. The choke structure 63 may have a comb shape in which a plurality of slits are formed at predetermined intervals. Further, when the choke structure 63 has a comb shape, the number of slits is not particularly limited.

  The inner glass 61 plays a role of constituting one surface of the heating chamber 34 when the door 31b is closed. Further, the inner glass 61 makes the heating chamber 34 visible when the door 31b is closed. The outer glass 62 plays a role of constituting the outer surface of the door 31b. Further, the outer glass 62 also makes the heating chamber 34 visible in the state where the door 31 b is closed as in the inner glass 61. In addition, although the material of the inner side glass 61 and the outer side glass 62 is not specifically limited, For example, it is good to comprise with a material with high heat resistance and good transparency.

  In addition, the microwave oven 31 is connected to the upper portion of the waveguide 33 and has a heating chamber 34 having a width-direction dimension (about 400 mm) larger than a depth-direction dimension (about 310 mm), and a food (a typical object to be heated) A flat mounting table 35 that is fixed in the heating chamber 34 for mounting (not shown) and is made of a low-loss dielectric material such as ceramic or glass and that can easily transmit microwaves, and a mounting in the heating chamber 34. A power feeding part (antenna space) 37 formed below the pedestal 35, a rotating waveguide 39 attached to the power feeding part 37 for rotating the microwave in the waveguide 33 into the heating chamber 34, and rotation A motor 41 as a typical driving means capable of rotating the waveguide 39, a control means 411 for controlling the direction of the rotating waveguide 39 by controlling the motor 41, and an origin of rotation of each rotating waveguide 39 Detect the original A photo-interrupter 36 which constitutes the detection mechanism, but with a.

  Incidentally, 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 58.

  On the other hand, the rotating antenna is connected to the coupling shaft as a flat plate without a bent portion, or has an opening in the flat plate, or has a partially bent portion but is not opposed to each other. It is assumed that an H surface and an E surface such as a wave tube cannot be formed. As a result, the rotating antenna is not restricted in the direction of microwave travel unlike the rotating waveguide, so it radiates upward from anywhere, and unlike the rotating waveguide, it emits less in the horizontal direction. , Will be emitted mainly upward.

  Further, a heater 401 capable of performing electrothermal heating is installed on the upper surface portion of the heating chamber 34. In addition, the heating chamber 34 has three stages of dish receivers that support the heating dish 402. Specifically, the heating chamber 34 includes an upper tray receiver 403, an intermediate tray receiver 404, and a lower tray receiver 405. The heating dish 402 has a microwave absorber (for example, ferrite) on the back side (mounting table 35 side) on which an object to be heated is not placed.

  Resin holders 207 (positioning spacers) are provided at the left and right ends of the heating dish 402 in the front-rear direction. The longitudinal dimension of the holder 207 is longer than the longitudinal dimension of the heating dish 402, and both front and rear ends of the holder 207 protrude from the heating dish 402. The dimension in the longitudinal direction of the holder 207 is substantially the same as the dimension from the front opening of the heating chamber 34 on the right side in FIG. 2 to the back wall of the heating chamber 34, that is, the depth dimension of the heating chamber 34.

  Therefore, when the heating dish 402 is locked to the dish receiving portions 403 to 405 of the heating chamber 34, the heating dish 402 is necessarily positioned in the heating chamber 34. That is, with respect to the left-right direction of the heating chamber 34, the holder 207 is arranged at a distance from the inner wall of the heating chamber 34 by the dimension in the short (width) direction of the holder 207. With respect to the front-rear direction (depth direction) of the heating chamber 34, the front and rear ends of the holder 207 come into contact with the inner wall of the heating chamber 34 and the door 31 b, thereby positioning the heating dish 402.

  This prevents a spark from being generated between the heating pan 402 and the inner wall of the heating chamber 34, and also allows the heating pan 402 and the heating to be formed through the holder 207 or by the front and rear ends of the holder 207. Through the gap with the inner wall of the chamber 34, microwaves can be supplied from the lower side of the heating dish 402 to the upper side, and the cooking performance can be improved.

  Note that the gap between the heating dish 402 and the inner wall of the heating chamber 34 is not formed only by the holder 207, but may be formed by the shape of the heating dish 402.

  And the operation part 31c is arrange | positioned at the front lower part of the door 31b. The operation unit 31c allows the user to select various cooking menus according to food and cooking contents. For example, it is possible to set a heating time or select a preset cooking menu such as “warming menu”, “thaw menu”, “thaw / warm menu”, and “grill menu” using the operation unit 31c. It can be done.

  Here, the “warming menu” refers to a cooking method in which food is heated by radiating microwaves toward the food.

  The “thawing menu” refers to a method of freezing food by radiating and heating a frozen food continuously or intermittently, a method of heating and thawing frozen food with superheated steam, or a method of thawing food by a combination thereof. Refers to the method of heating food.

  The “thaw / warm menu” refers to the direction of the front opening 38 of the heating chamber 34, which is a direction in which the open portion 58 of the rotating waveguide 39 easily goes to the upper surface of the heating dish, and the peripheral edge of the heating dish 402 and the inner wall of the heating chamber 34. In this case, the heating plate upper surface heating mode with a large supply amount is performed in the microwave supply to the upper surface of the heating plate 402 toward the front opening 38 of the heating chamber 34, and is placed on the heating plate 402. After thawing frozen food, cooking the thawed food in the same way as the “warm menu”.

The “grill menu” refers to a method of heating food through the heating dish 402 by raising the temperature of the heating dish 402 on which the food is placed, or a combination of the heated heating dish 402 and the heater. Refers to the cooking method of heating.

  Based on the output signal from the operation unit 31 c, the control unit 411 executes these menus by controlling the magnetron 32 and the motor 41.

  The microwave oven 31 according to the first embodiment is configured to centrally heat the heating dish 402 by controlling the opening 58, which is a portion having a high radiation directivity, of the rotating waveguide 39 in a predetermined direction. The specific control method will be described later.

  The coupling portion 46 is made of a substantially cylindrical conductive material that passes through a substantially circular coupling hole 44 provided at the boundary surface between the waveguide 33 and the heating chamber bottom surface 42 (mounting table). The radiating portion 48 is made of a conductive material having a larger area in the horizontal direction than the vertical direction, and is integrally connected to the upper end of the coupling portion 46 by caulking or welding. The rotating waveguide 39 includes a coupling portion 46 and a radiating portion 48.

  Further, the rotating waveguide 39 is configured to be fitted to the shaft 50 of the motor 41 so that the center of the coupling portion 44 becomes the center of rotation driving. The radiating portion 48 has a radiation directivity because the shape is not constant with respect to the direction of rotation. The center of rotation of the rotating waveguide 39 is arranged at the center in the heating chamber 34.

  The radiating portion 48 has a trapezoidal shape in which the radiating portion upper surface 52 has a base on the open portion 58 side, and three of the four sides excluding the bottom have a radiating portion bent portion 54 bent toward the heating chamber bottom surface 42 side. And it is set as the structure which restrict | limits the radiation | emission of the microwave to the outer side of the 3 sides.

  In this configuration, when a general food is heated uniformly by the “warming menu”, it is not necessary to be particular about the place of placement as in the conventional microwave oven, and the rotating waveguide 39 is also rotated at a constant speed as in the conventional case. Good.

  In addition, when the frozen food placed on the placing table 35 in the heating chamber 34 is heated by the “thaw menu”, the rotating waveguide 39 rotates and stops at a predetermined time interval.

  Further, when the frozen food placed on the heating dish 402 is heated by the “thaw / warm menu”, the heating dish 402 containing the frozen food is set in a predetermined dish receiving unit, for example, the lower dish receiving unit. By starting the operation, the open portion 58 of the rotating waveguide 39 is directed to the front opening 38 of the heating chamber 34 to thaw the frozen food, and after thawing, cooking is performed.

  Furthermore, when the food placed on the heating dish 402 is heated by the “grill menu”, the operation of the rotating waveguide 39 is performed with the opening 58 of the rotating waveguide 39 facing a predetermined position. Stop.

  The predetermined position is determined by the relationship with the size of the heating chamber 34, the position of the heating dish 402, and the like, and is determined in advance experimentally. As a result of the experiment, for example, as shown in FIG. 2, when the opening 58 of the rotating waveguide 39 faces the door 31 b (front opening 38), the heating placed on the lower tray receiver 405 When the result is that the microwave is concentrated on the plate 402 and the temperature of the heating plate 402 is increased efficiently, the position of the rotation wave guide when the heating plate 402 is placed on the upper plate receiving unit 403 is obtained. This is stored in the control unit 411 as the stop position of the tube 39.

In the microwave oven 31 of the first embodiment, the control unit 411 stores the angle information (stop position) of the rotating waveguide 39 with the origin detected by the origin detection mechanism having the photo interrupter 36 as a reference. In the microwave oven 31 according to the first embodiment, as shown in FIG. 3A, the origin position (0 degree) is set when the opening 58 of the rotating waveguide 39 faces the door 31b. .

  Further, as shown in FIG. 3B, the control means 411 of the microwave oven 31 is configured such that when the opening 58 of the rotating waveguide 39 faces the right side surface of the heating chamber 34, the middle tray receiver 404. If the result is that the microwave is concentrated on the heating dish 402 placed on the plate and the heating dish 402 is efficiently heated, the position (45 degrees counterclockwise from the origin) is set to the middle tray holder. This is stored in the control means 411 as the stop position of the rotating waveguide 39 when the heating dish 402 is placed on the part 404.

  Further, as shown in FIG. 3C, the control means 411 of the microwave oven 31 is configured such that when the opening 58 of the rotating waveguide 39 faces the left side of the heating chamber 34, the upper tray receiver 403. When the result is that the microwaves are concentrated on the heating dish 402 placed on the plate and the heating dish 402 is efficiently heated, the position (315 degrees counterclockwise from the origin) This is stored in the control means 411 as the stop position of the rotating waveguide 39 when the heating dish 402 is placed on the part 405.

  As described above, the microwave oven 31 according to the first embodiment controls the direction of the rotating waveguide 39 according to the position of the heating dish 402, and directs the rotating waveguide 39 in a predetermined direction. For example, a stepping motor may be used as the motor 41, or a means for detecting the reference position and controlling the energization time even if the motor 41 has a constant rotation may be considered.

  In the microwave oven 31 of the first embodiment, a stepping motor is used as the motor 41, and the above-described origin detection mechanism is provided on the shaft 50 of the motor 41. As shown in FIG. 4, the origin detection mechanism includes a disc 36 a having a shaft as a central axis, and a photo interrupter 36. The circular plate 36a is provided with a rectangular slit 36b.

  The disc 36a is attached to the shaft of the shaft 50 of the motor 41 that rotates the rotating waveguide 39, and rotates so as to block the optical path of the photo interrupter 36 that includes a light emitting element and a light receiving element.

  With this configuration, when the slit 36b passes through the optical path of the photointerrupter 36, there is nothing to block the optical path, so that it is possible to detect the passage time of the slit 36b. Therefore, by setting the position of the slit 36b as the origin of the rotating waveguide 39, the origin of the rotating waveguide 39 can be detected by the photo interrupter 36 attached to each motor 41.

  Next, the configuration of the control unit 411 will be described. As shown in FIG. 5, the control means 411 controls the operation of the rotating waveguide 39 by controlling the operation of the motor 41, and the position information (angle information) of the rotating waveguide 39. And a storage unit 413 that stores the information.

  The antenna control unit 412 refers to necessary information from the storage unit 413 according to a command signal from the operation unit 31c, controls the motor 41, and controls the operation of the rotating waveguide 39. The storage unit 413 stores position information of the rotating waveguide 39 suitable for heating the heating dish 402 for each position (upper, middle, and lower) where the heating dish 402 is placed in the heating chamber 34. Yes. Specifically, position information 414 (origin) for the lower tray receiver, position information 415 for the middle tray receiver (45 degrees counterclockwise from the origin), and position information 416 for the upper tray receiver ( 315 degrees counterclockwise from the origin).

  Next, the operation of the microwave oven 31 according to the first embodiment will be described with reference to FIG.

  First, the microwave oven 31 is turned on and enters a standby state (S101). Depending on the content of the heated item (food type) that the user (user) wants to heat, the “warm menu”, “thaw menu”, “thaw / warm menu”, “grill menu”, or other menu select. When the “warming menu” is selected (S102-A), the operation unit 31c outputs a signal notifying the antenna control unit 412 that the “warming menu” has been selected.

  Upon receiving the output signal, the antenna control unit 412 rotates the rotating waveguide 39 at a constant speed by rotating the motor 41 at a constant speed (S103). Subsequently, the control means 411 operates the magnetron 32 and starts the heat treatment (S104). Then, after a predetermined time has elapsed (S105), the operations of the rotating waveguide 39, the magnetron 32, etc. are stopped, and the heating process of the “warming menu” is completed (S106).

  When the “thawing menu” and “thaw / warm menu” are selected (S102-B), the operation unit 31c selects “thaw menu” and “thaw / warm menu” for the antenna control unit 412. Output a signal that tells you. The antenna control unit 412 that has received the output signal first determines from the output signal whether the position where the heating dish 402 is placed is in the lower stage (S107). In addition, “defrost menu” and “thaw / warm menu” can be selected such as meat, fish or pizza.

  Next, the antenna control unit 412 controls the operation of the motor 40 by referring to the corresponding position information from the storage unit 413 based on the position information determined in S107, and the operation of the motor 40 by referring to the position information 416. Is controlled to rotate and stop the rotating waveguide 39 in a direction in which the microwave easily goes around the upper surface of the heating dish 402, for example, in the direction of the front opening 38 (origin) (S108).

  After the rotating waveguide 39 stops at a predetermined position, the control means 411 operates the magnetron 32 and starts the heat treatment (S109). Thereafter, the magnetron 32 is turned on and off, the rotating waveguide 39 is rotated, and the origin is stopped (S110). After a predetermined time (S111), if the selected menu is not the “thaw / warm menu”, the magnetron 32 is turned on. Is stopped, and the heating process of the “thawing menu” ends (S106).

  If the selected menu is the “thawing / warming menu”, the above “warming menu” is continuously executed (S103), and after a predetermined time (S105), the operation of the magnetron 32 is stopped, The heating process of the “warming menu” ends (S106).

  When “Grill Menu” is selected (S102-C), the operation unit 31c outputs a signal to the antenna control unit 412 that the “Grill Menu” is selected. The antenna control unit 412 that has received the output signal first determines from the output signal whether the position where the heating dish 402 is placed is the upper, middle, or lower stage (S113). The “Grill menu” allows you to select the type of food to be grilled, such as roast beef, roast chicken, pizza, paella, etc. The position of the mounting plate is stored in the upper, middle, and lower levels in advance, and the position of the mounting plate is determined by selecting the type of food to be grilled in the “grill menu”. Instead, for example, each dish receiving unit 403 to 405 may be provided with detection means, and the dish position may be determined based on a signal from the detection means.

Next, the antenna control unit 412 controls the operation of the motor 40 with reference to the corresponding position information from the storage unit 413 based on the position information determined in S113. For example, the operation unit 31c
If the grill menu is selected in the upper stage, the operation of the motor 40 is controlled with reference to the upper position information 414, and the rotating waveguide 39 is rotated counterclockwise from the origin to a position of 90 degrees. (S114).

  After the rotating waveguide 39 stops at a predetermined position, the heater 401 is driven (S115). Subsequently, the control means 411 operates the magnetron 32 and starts the heat treatment (S116). After a predetermined time has elapsed (S117), the operations of the rotating waveguide 39, the heater 401, the magnetron 32, etc. are stopped, and the heating process of the “grill menu” is completed (S106).

  With the above configuration, the microwave oven 31 of the first embodiment has three (upper, middle, and lower) tray receivers 403 to 405 in the heating chamber 34, and the cooking menu depends on the tray receiver position. And various foods can be cooked with the “grill menu”.

  For example, in the case of the upper stage (dish receiving part 403), it is used when cooking on a conventional grill with thin ingredients such as fish and chicken thighs. In the case of the middle stage (dish receiving portion 404), it is used when cooking a large food such as roast beef or roast chicken. In the case of the lower stage (dish receiving part 404), although the rear surface heating power such as pizza and paella is necessary, the upper surface improves the cooking performance by taking a distance from the upper surface heater because the heating power may be soft. Is.

  Moreover, the microwave oven 31 of this Embodiment 1 can bake the lower surface of a cooking thing by making a ferrite which is a microwave absorber affixed on the lower surface of the heating plate 402 absorb a microwave and to generate heat. become. Further, the upper surface of the cooked food can be cooked by heating the heater 401 with the heater 401 disposed on the upper surface of the heating chamber 34. Furthermore, in order to efficiently heat the back surface of the heating dish 402, the stop position of the rotary waveguide 39 of the microwave heating cooker is controlled by the position of the dish receiving portion.

  Since the microwave waveform changes depending on the position where the heating dish 402 is placed, the temporary stop position of the rotating waveguide 39 is different, but the stop position is obtained in advance by experiments as described above, This is stored in the storage unit 413. By providing the motor 41 with the origin detection mechanism, it is possible to accurately control the stop position of the rotary waveguide 39, and the highest efficiency heating can be realized at each of the tray receivers 403 to 405 positions. At the same time, the number of microwaves propagating to the upper space (the space where the food is placed) of the heating dish 402 is reduced, so that the moisture inside the food can be prevented from being excessively evaporated.

  In the description of the microwave oven 31 of the first embodiment, the example in which the rotating waveguide 39 is stopped when the thawing / warming menu or the grill menu is selected has been described. However, the operation control of the rotating waveguide 39 is performed here. It is not limited. For example, if the rotating waveguide 39 continues to radiate microwaves into the heating chamber 34 while stopped at a predetermined position, the rotating waveguide 39 itself may be excessively heated and melt.

  In view of this point, the antenna control unit 412 of the control unit 411 may reciprocally swing the rotating waveguide 39 about a predetermined angle (for example, ± 5 degrees) around the target angle (stop position). Thereby, deterioration of the rotating waveguide 39 can be prevented without substantially affecting the heating effect on the heating pan. In addition, since the rotating waveguide continues to stop during the microwave radiation, the microwave is prevented from being excessively concentrated on a part of the rotating waveguide 39 to prevent overheating. Although this reciprocating rocking | fluctuation operation | movement may be performed from the time of a heating start, it is good also as a structure started after predetermined time progress (for example, 30 seconds-1 minute after) from the time of a heating start.

In order to execute this reciprocating swinging operation, the control means 411 includes a stop upper limit time storage unit that stores in advance an upper limit time that allows the rotating waveguide 39 to stop, and the rotating waveguide stops. And a reciprocal angle storage unit that stores an angle at which the rotary waveguide 39 is reciprocally swung.

  Alternatively, the rotating waveguide 39 may be rotated by a predetermined angle (for example, 5 degrees) after a predetermined time has elapsed from the start of heating in the grill menu (for example, after 30 seconds to 1 minute).

  For the same purpose, the rotational speed of the rotating waveguide 39 may be controlled. For example, the structure may be such that the microwave is concentrated on the heating dish 402 by rotating the rotating waveguide 39 slowly in the vicinity of a predetermined position and rotating the others at a constant speed. In this case as well, an experiment is performed in advance to determine beforehand in which position the microwave is concentrated on the heating dish by controlling the rotating waveguide at which speed.

  The control means 411 stores the time when the rotating waveguide 39 is at a predetermined stop position (angle) as the origin. The control unit 411 executes, for example, an origin detection mode for confirming the origin of the rotating waveguide 39 together with the “warming menu” and the “grill menu” before or after the heat treatment.

  During the origin detection mode, the angle of the rotating waveguide 39 cannot be specified, and if the microwave is oscillated as it is, an unintentional heating state may be caused and cause a defect. Therefore, the control unit 411 performs control to stop the operation of the magnetron while the rotary waveguide 39 is being driven in the origin detection mode.

  Further, the control unit 411 performs the origin detection mode after the end of the heating process, and waits for non-heating with the origin detected. Thereby, it is possible to prevent the standby time for detecting the origin from occurring before starting the heat treatment.

  Further, the control means 411 rotates the rotating waveguide 39 at a constant speed in the initial stage of starting heating even at the time of the grill menu, and when the difference in the temperature distribution in the heating chamber 34 begins to occur, The rotating waveguide 39 may be shifted to operation control based on position information of the storage unit 413.

  In order to detect the temperature distribution, a temperature detecting means as shown in FIG. 7 may be provided. This temperature detection means includes a plurality of infrared detection elements 13 arranged in a line on the substrate 19, a case 18 that houses the entire substrate 19, and a case 18 that is perpendicular to the direction in which the infrared detection elements 13 are aligned. And a stepping motor 11 that moves in the intersecting direction.

  On the substrate 19, a metal can 15 that encloses the infrared detection element 13 and an electronic circuit 20 that processes the operation of the infrared detection element 13 are provided. The can 15 is provided with a lens 14 through which infrared rays pass. Further, the case 18 is provided with an infrared passage hole 16 through which infrared light passes and a hole 17 through which a lead wire from the electronic circuit 20 passes.

  With this configuration, when the stepping motor 11 rotates, the case 18 can be moved in a direction perpendicular to the direction in which the infrared detection elements 13 are aligned. When the stepping motor 11 of the temperature detecting means is reciprocally rotated, the temperature distribution in almost all regions in the heating chamber 34 can be detected.

In addition, the case where there is one rotating waveguide has been described so far, but the number of rotating waveguides 39 is not limited to this, and may be two or more. For example, as shown in FIG. Two rotating waveguides 90 and 91 may be provided in the width direction of the heating chamber 34. In the state shown in FIG. 8, the open portions 92 and 93 of the rotary waveguides 90 and 91 face the vicinity of the center of the heating chamber 34. In which position relationship between the tubes 90 and 91 is experimentally determined in advance whether the microwave is concentrated on the heating dish 402.

  By using a plurality of rotating waveguides 39, the number of combinations increases at the stop positions of the rotating waveguides 90 and 91 (for example, one rotating waveguide 90 is the origin position and the other rotating waveguide 91 is the other). Is 90 degrees counterclockwise from the origin), and the microwave can be concentrated on the microwave absorber of the heating dish 402. Therefore, the heating efficiency of the heating dish 402 can be improved. On the other hand, it becomes possible to intensively heat the right half or the left half of the heating dish 402, and the upper half or the lower half area, and the variety of cooking methods is widened.

  In this embodiment, microwaves are radiated from below the heating chamber 34 into the heating chamber 34. However, the power supply chamber 37 is provided above the heating chamber 34, and microwaves are radiated from above the heating chamber 34. Then, the microwave may be circulated to the lower surface of the heating dish 402.

  Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

  As described above, the present invention controls a portion of the rotating waveguide disposed in the heating chamber having a high radiation directivity to a predetermined direction, and performs desired heating on the upper and lower surfaces of the heating pan supported by the tray receiver. Because it can be heated with force, an optimum cooking finish according to the selected menu can be obtained.

31 Microwave oven (microwave heating device)
31a body 31b door 31c operation unit 32 magnetron (microwave generating means)
33 Waveguide 34 Heating chamber 35 Mounting table 37 Feeding portion 38 Front opening 39 Rotating waveguide 41 Motor (driving means)
42 Heating chamber bottom (mounting table)
58 Opening portion 90 Rotating waveguide 91 Rotating waveguide 92 Opening portion 93 Opening portion 207 Holder (positioning spacer)
402 Heating pan 403 Upper tray receiving portion 404 Interruption tray receiving portion 405 Lower tray receiving portion 406 Microwave absorber 411 Control means

Claims (7)

A heating chamber in which a door is provided in the front opening to store an object to be heated;
A microwave-permeable mounting table constituting the bottom surface of the heating chamber;
A metal heating pan that is detachably mounted in the heating chamber and places an object to be heated;
A tray receiver that supports the heating dish provided in a plurality of stages in the vertical direction in the heating chamber;
Microwave generation means;
A waveguide for transmitting microwaves from the microwave generating means;
A rotating waveguide that radiates the microwave from the open portion of the waveguide to the heating chamber;
Driving means for rotationally driving the rotating waveguide;
A power feeding unit formed below the mounting table and provided with the rotating waveguide;
An operation unit for selecting a cooking menu of the object to be heated;
Control means for controlling the drive means based on an output signal from the operation unit,
Resin positioning spacers are provided on the left and right ends of the heating pan in the front-rear direction from the front opening of the heating chamber to the inner surface of the heating chamber, and the control means responds to an output signal from the operation unit. The direction of the opening is made different, and the microwave supply amount from the upper and lower surfaces of the heating dish supported by the dish receiving unit is controlled, and the microwave supply amount to the upper surface of the heating dish is cooked. A microwave heating cooker that controls the initial operation to be more than after the initial operation. The microwave heating cooker according to claim 1, wherein a microwave absorber is provided on the lower surface of the heating dish. The temperature detecting means for detecting the temperature of the object to be heated or the heating dish in the heating chamber is provided, and the control means is configured to control the operation of the rotating waveguide based on the detection result of the temperature detecting means. 2. The microwave heating cooker according to 2. The microwave heating cooker according to any one of claims 1 to 3, wherein the control unit is configured to control the driving unit so that the opening of the rotating waveguide is stopped at a position facing a predetermined direction. The microwave heating according to any one of claims 1 to 4, wherein the control means is configured to control the driving means so that the opening of the rotating waveguide is stopped at a position facing the front opening direction of the heating chamber. Cooking device. The microwave heating cooker according to any one of claims 1 to 5, wherein the control means is configured to control the driving means so that the open portion of the rotating waveguide swings in the vicinity of a position facing a predetermined direction. . The control means is configured to rotate the rotating waveguide during heating by the microwave and to control the driving means so that the open portion of the rotating waveguide is decelerated near a predetermined position. The microwave heating cooker as described in any one of.