JP2010255872A - Cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To combine uniform heating reduced in unevenness in heating by uniformly irradiating microwave, and local heating for concentrating the microwave to a specific heated object, in a heating cooker having a rotating antenna. <P>SOLUTION: This heating cooker has a heating chamber 2 for heating food, a magnetron 51 disposed at a lower part of the heating chamber 2, a wave guide 52 for propagating the microwave generated in the magnetron 51, a connection hole 53 disposed between the wave guide 52 and the heating chamber 2, a central conductor 56 penetrating through the connection hole 53, a dielectric shaft 55 connected to the central conductor 56, an antenna motor 54 driving the dielectric shaft 55, and the rotating antenna 60 composed of a conductor flat plate electrically connected with the central conductor 56. The rotating antenna 60 has the shape formed by radially disposing six sheets of plate plates from the center of rotation at intervals of 60 degrees, and a length from the center of rotation of one flat plate A61 among the flat plates, is shorter than a length from the center of rotation, of the other flat plates B62. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cooking device such as a microwave oven provided with heating means for heating food and control means for controlling the heating means.

  In recent years, in this type of cooking device, the capacity of the heating chamber has been increased so that more objects to be heated (food items) can be heated at one time.

  Moreover, in order to make it easy to take out food, the shape of the heating chamber is increasing from a shape close to a conventional cube to a rectangular parallelepiped shape that is long horizontally.

  Furthermore, it is important to heat the food placed in the heating chamber without unevenness, and in particular, in a cooking device that heats food using microwaves, various measures are taken to reduce food unevenness in heating. Have been devised.

  For example, the structure to reduce the heating unevenness of the food by rotating the object to be heated by rotating the mounting table on which the food is placed and uniformly irradiating the food with the microwave irradiated from one direction. Cookers are known.

  Also, recently, to accommodate larger foods, the inside of the heating chamber is widened and a rotating antenna that diffuses microwaves is provided outside the heating chamber, and the object to be heated is changed by changing the electrolytic distribution in the heating chamber. It has been attempted to reduce the heating unevenness by devising the shape and control method of the rotating antenna.

  For example, Patent Document 1 describes a high-frequency heating apparatus in which a rotating antenna is provided in a high-frequency supply chamber below a heating chamber. In the heating apparatus, the object to be heated is rotated while rotating the rotating antenna at a constant speed. By heating, the object to be heated in the heating chamber is heated uniformly.

  Also, the one described in Patent Document 2 is provided with a protrusion on the outside of the rotating antenna, detects the temperature information of the food in the heating chamber with an infrared sensor, and rotates so that the protrusion is directed to the low temperature portion of the food. This is a high-frequency heating device that temporarily stops the antenna.

  This uses the fact that microwaves tend to concentrate on the protrusions provided on the rotating antenna, and focuses the food at low temperatures by stopping the rotating antenna with the protrusions facing the food at low temperatures. And a plurality of foods having different shapes and weights are heated to the same temperature at a time.

  Further, what is described in Patent Document 3 is a microwave oven in which an auxiliary antenna is added in parallel with the rotating antenna in addition to the rotating antenna, and by providing an auxiliary antenna having a larger outer diameter than the rotating antenna, It is possible to adopt a rotating antenna with a smaller outer diameter and higher directivity than a conventional rotating antenna that is limited by the outer diameter, and it is possible to control the microwave distribution in the heating chamber more freely. is there.

  Moreover, what was described in patent document 4 is the high frequency heating apparatus which comprised the rotating antenna by protruding several metal pieces radially from the circumference | surroundings of a metal disc.

  In this heating device, by using the rotating antenna described above, the electric field strength changes over time while concentrating microwaves at the center of the heating chamber, so that heating efficiency can be increased and uneven heating can be reduced. Can prevent microwave leakage.

JP 2002-110339 A JP 2002-324660 A JP 2002-231437 A JP 2002-299036 A

  In recent cooking devices, with the expansion of the capacity of the heating chamber, there is an increasing need for not only heating the food in the heating chamber evenly but also for locally heating only a part of the heating chamber.

  For example, food placement methods in the heating chamber are diversified, and food is often placed in places other than the center of the heating chamber, or multiple foods are placed and heated at one time. There is a demand for efficient heating of food no matter where it is placed in the heating chamber.

  In addition, storing a plurality of foods having different temperatures and capacities in the heating chamber is also increasing. For example, there is an increasing demand for heating a frozen food and a refrigerated food to the same temperature.

  In addition, with the growing awareness of global environmental protection, energy-saving performance is required for cooking devices. In order to cook food with less energy, it is necessary to concentrate microwaves on the food and heat it.

  In this way, even when a relatively small food is placed in a large heating chamber and heated, only the range where the food is placed is concentrated and heated, or food that is low in temperature and difficult to warm is concentrated. There has been a demand for local heating of only a specific part of the heating chamber, such as heating to a low temperature.

  On the other hand, in a rectangular parallelepiped-shaped heating chamber in which the depth and width are greatly different compared to a heating chamber having a length and width that are substantially equal, the distribution of microwaves in the depth and width directions of the heating chamber Unlikely, uneven heating tends to occur.

  Moreover, with the expansion of the capacity of the heating chamber, the amount and size of foods to be cooked are also increasing, and further reduction in heating unevenness is required compared to the conventional case.

  As described above, with the expansion of the capacity in the heating chamber, the heating by the microwave is required to be uniform heating that uniformly heats the entire heating chamber and local heating that intensively heats a part of the heating chamber. It has become to.

  However, it has been difficult to achieve both uniform heating and local heating in a conventional cooking device having a structure in which the heating chamber is heated uniformly.

  For example, as shown in Patent Document 1, six flat plates are arranged radially from the rotation center at an interval of 60 degrees, and among the six flat plates, the length from the rotation center of three adjacent flat plates is different. With the rotating antenna shape that is shorter than the length from the center of rotation of the three flat plates, it is possible to reduce the heating unevenness of the object to be heated by rotating the rotating antenna, but the microwave is only applied to a part of the rotating antenna. Therefore, it is difficult to intensively heat a specific position in the heating chamber.

  Patent Document 1 describes that the microwaves are concentrated by temporarily stopping when the rotating antenna is at a specific angle. However, when the rotating antenna is composed of three short flat plates and three long flat plates, the Since the waves are dispersed and concentrated on three short flat plates, the directivity of the rotating antenna itself becomes weak, and it is difficult to concentrate the microwaves in a part of the heating chamber even when the rotating antenna is stopped.

  In addition, Patent Document 2 describes that by using an infrared sensor, microwaves are concentrated on a food having a low temperature to heat the food so that temperature unevenness is uniform. Since six flat plates are arranged at regular intervals and at 60 degree intervals, microwaves tend to concentrate on the protrusions, but there is not much directivity, and the microwaves are concentrated in a part of the heating chamber. It is difficult to control the heating distribution.

  In addition, by using an infrared sensor, when microwaves are concentrated on food at a low temperature, microwaves are concentrated on the object to be heated while the object to be heated is lower than the temperature in the heating chamber. When the heated object is heated to some extent and no object to be heated is placed around it, control is performed so that the microwave does not concentrate on the object to be heated. Heating efficiency may decrease.

  Further, after using oven heating or the like, the infrared sensor cannot easily measure the state of the object to be heated when the heating chamber is at a high temperature, and the object to be heated cannot be efficiently heated.

  Further, as shown in Patent Document 3, when an auxiliary antenna is provided in addition to the rotating antenna, the structure around the rotating shaft becomes complicated, and it is difficult to manufacture and control the rotating antenna.

  In addition, the volume of the rotating antenna and the drive unit is larger than when the auxiliary antenna is not provided, and it is difficult to store in the heating cooker, so the heating cooker becomes larger than necessary, or conversely the heating chamber volume is compressed. Sometimes it was getting smaller.

  Furthermore, since the microwave propagates separately from the rotating antenna and the auxiliary antenna, unevenness in the heating chamber is easy to reduce, but it is difficult to intensively heat a specific object to be heated. Further, since the structure is complicated, there is a drawback that the manufacturing cost is increased.

  Moreover, as shown in Patent Document 4, in the case where six flat plates are arranged radially from the rotation center at an interval of 60 degrees, the microwave can be concentrated in the central portion of the heating chamber. It was difficult to heat a specific part of a large heating chamber intensively.

  Furthermore, in conventional cooking devices with a small capacity, food is often placed in the center of the heating chamber, so microwave heating is performed assuming that the food is placed in the center of the heating chamber. However, recently, in a heating cooker with a larger heating chamber capacity, when the microwave is heated assuming that the food is placed in the center of the heating chamber, When it was not placed in the center of the heating chamber, the microwave did not concentrate on the food, and it was difficult to heat.

  In addition, when a plurality of foods are stored in the heating chamber, microwaves are difficult to concentrate on the food, and there are foods that are heated and foods that are difficult to heat.

  The present invention solves at least one of the above problems.

  The present invention is made to solve the above-described problems. In claim 1, the main body of the heating cooker, the heating chamber for heating the food, and the heating chamber disposed below the heating chamber. A magnetron for generating microwaves for heating food, a waveguide for propagating microwaves generated by the magnetron, a coupling hole provided between the waveguide and the heating chamber, and penetrating through the coupling hole A rotating antenna composed of a center conductor, a dielectric shaft connected to the center conductor, a drive unit that drives the dielectric shaft, and a conductor plate electrically connected to the center conductor, The rotating antenna has six flat plates arranged radially from the rotation center at an interval of 60 degrees, and the length from the rotation center of one of the six flat plates is the length from the rotation center of the other flat plate. It is shorter than that.

  In claim 2, if one flat plate having a short length from the rotation center of the rotating antenna is a flat plate A and the other flat plate is a flat plate B, the length from the rotation center of the flat plate A is 1 / (microwave wavelength). 4, the length from the rotation center of the flat plate B is substantially the same as 1/2 of the microwave wavelength.

  According to a third aspect of the present invention, the width of the flat plate A and the flat plate B constituting the rotating antenna is set to a length of 1/4 to 1/8 of the microwave wavelength.

  In Claim 4, it has a plurality of weight detection means for detecting the weight and position of food in the lower part of the heating chamber, and when the flat plate A of the rotating antenna is located on the center of gravity side of the object to be heated, the rotating antenna Is temporarily stopped.

  According to the first aspect of the present invention, since directivity can be given so that the microwaves are concentrated on one short flat plate constituting the rotating antenna, the object to be heated is rotated while the rotating antenna is rotated. It is easy to control the heating state of the object to be heated, for example, by heating uniformly and heating strongly in one direction while the rotating antenna is stopped.

  In addition, since six flat plates are provided, only one of them has a short length from the rotation center, so that it is possible to irradiate microwaves more strongly from one short flat plate. Therefore, it is easy to irradiate a microwave in a specific direction, and it is easy to control local heating. Moreover, heating efficiency can be improved by concentrating the microwave on the object to be heated.

  In addition, since the rotating antenna has a shape having strong directivity, it is possible to control uniform heating and centralized heating regardless of where the heated object is placed, regardless of where the heated object is placed.

  Further, since the interval between the flat plates is 60 degrees, radio wave interference between the flat plates can be suppressed, and the directivity of the microwave irradiated from one short flat plate can be improved.

  According to claim 2, the length from the rotation center of the flat plate A constituting the rotating antenna is substantially the same as ¼ of the microwave wavelength, and the length from the rotation center of the flat plate B is the microwave wavelength. Therefore, the electric field strength is maximized at the tip of the flat plate A, and the electric field strength due to the microwave is small at the tip of the flat plate B. Therefore, the microwave irradiated by the rotating antenna is hardly irradiated from the flat plate B, and most of the microwave is irradiated from the flat plate A. Therefore, the directivity of the rotating antenna can be further strengthened, and the local heating is performed. Easy to do.

  Further, since the length from the rotation center of the flat plate A is substantially the same as ¼ of the microwave wavelength, the electric field strength at the tip of the flat plate A is maximized, and the microwave can be efficiently irradiated from the flat plate A. Therefore, the heating efficiency of the object to be heated can be improved.

  Further, since the length from the rotation center of the flat plate B is substantially the same as ½ of the microwave wavelength, the electric field intensity at the tip of the flat plate B is almost zero, and the microwaves from the portion other than the flat plate A Therefore, it is possible to perform efficient and uniform heating by rotating the rotating antenna irradiated from the rotating antenna.

  In addition, the angle between the flat plate A and the flat plate B is 60 degrees, and when the length from the rotation center of the flat plate B is substantially the same as ½ of the microwave wavelength, the tips of the flat plate A and the flat plate B are Is approximately the same length as 1/2 of the microwave wavelength, and the interference of radio waves at the tips of the flat plate A and the flat plate B can be minimized, so that the microwave irradiated from the flat plate A is irradiated to the outside without being weakened. It is possible to efficiently heat the object to be heated.

  Further, the outer shape of the rotating antenna can be made approximately the same length as the microwave wavelength, and the shape can be reduced in size while maintaining and improving the performance of the rotating antenna.

  According to the third aspect, since the width of the flat plate A and the flat plate B is shorter than ¼ of the microwave wavelength, the microwave is hardly transmitted in the width direction of the flat plate A and the flat plate B, and the center direction of the rotating antenna. The microwaves are transmitted only in the direction radially toward the outer periphery. In addition, since the widths of the flat plate A and the flat plate B are longer than 1/8 of the microwave wavelength, it is possible to prevent sparks caused by excessive concentration of microwaves on the tips of the flat plate A and the flat plate B.

  Therefore, it is possible to transmit microwaves only in the outer peripheral direction of the rotating antenna while preventing sparks and ensuring safety, thereby improving the heating efficiency by irradiating more microwaves to the outside. be able to.

  According to the fourth aspect, the weight detecting means for detecting the weight and the position of the heated object is provided, and when the flat plate A of the rotating antenna is located on the center of gravity side of the heated object, the rotating antenna is temporarily driven. By stopping, it is possible to intensively heat a portion of the object to be heated that is large in quantity and difficult to warm up.

  In addition, in the case where a plurality of objects to be heated are heated at a time, the plurality of objects to be heated can be uniformly heated at a time by intensively heating the heavier objects to be heated.

  In addition, when one object to be heated is heated, the microwaves are concentrated on the placement position of the object to be heated. Therefore, regardless of the placement position, the heating object can be placed anywhere in the heating chamber. It is possible to heat well.

  Further, even when a large object to be heated is heated, the heating unevenness can be alleviated by intensively heating a heavier part of the object to be heated.

It is a top view of the rotation antenna shape in the 1st example of the present invention. 1 is an exploded perspective view of a heating cooker according to a first embodiment of the present invention. It is front sectional drawing of the cooking-by-heating machine by the 1st Example of this invention. It is explanatory drawing of the microwave absorptivity calculation result at the time of the heating using the 1st Example of this invention.

  Hereinafter, the cooking device of the present invention will be described by taking a household electric microwave oven provided with a hot air heater as a heating means as an example.

  In the present invention, if a magnetron for irradiating microwaves is provided, other household cooking appliances such as a steam microwave oven equipped with a function of generating steam, commercial cooking appliances such as a steam convection oven, gas It can also be applied to a cooking device such as an oven.

  A cooking device according to a first embodiment of the present invention will be described with reference to FIGS.

  In the figure, the heating cooker 1 of this embodiment has a structure in which a heating chamber 2 and a machine room 3 provided below the heating chamber 2 are covered with a cabinet 11, and food is placed in the heating chamber 2. It is a heating cooker that performs cooking by heating. A door 4 is provided in front of the heating chamber 2, and food is taken into and out of the heating chamber 2 by opening and closing the door 4.

  A waveguide 52 is disposed below the heating chamber 2, and a magnetron 51 is installed at the end of the waveguide 52. A coupling hole 53 is provided between the waveguide 52 and the heating chamber 2, a central conductor 56 is provided so as to penetrate the coupling hole 53, and a rotating antenna 60 is disposed above the central conductor 56. Yes.

  In this embodiment, the central conductor 56 has a cylindrical shape, and the rotary antenna 60 has a flat plate shape, both of which are made of metal and fixed to each other and are electrically connected. Therefore, the microwave generated in the magnetron 51 is transmitted through the waveguide 52 and supplied into the heating chamber 2 through a coaxial path formed by the coupling hole 53 and the central conductor 56, and is transmitted into the heating chamber 2 by the rotating antenna 60. Irradiated while being diffused.

  A dielectric shaft 55 is connected to the center conductor 56, and the dielectric shaft 55 is connected to an antenna motor 54 that is a drive unit installed outside the waveguide 52. Since the dielectric shaft 55 is made of a material having a low dielectric constant such as a fluororesin, the dielectric shaft 55 hardly affects the microwave and does not hinder the propagation of the microwave inside the waveguide 52. Therefore, it is possible to control the microwave distribution in the heating chamber 2 by driving the antenna motor 54 and rotating the central conductor 56 and the rotating antenna 60 via the dielectric shaft 55.

  The shape of the rotating antenna 60 in the present embodiment is the shape shown in FIG.

  In this embodiment, an aluminum plate having a thickness of 1 mm is used, but the thickness and material are not particularly limited as long as the plate is made of metal.

  The rotating antenna 60 has a shape in which one rectangular flat plate A61 having a width of 20 mm and a length of 30 mm is combined with five rectangular flat plates B62 having a width of 20 mm and a length of 60 mm, and includes one flat plate A61 and five flat plates A61. The flat plates B62 are arranged radially at intervals of 60 degrees with the central conductor 56 as a base point.

  The central conductor 56 has a cylindrical shape with a diameter of 15 mm, and is joined to a central position where one flat plate A61 and five flat plates B62 are combined. Therefore, the rotating antenna 60 in the present embodiment is configured to rotate around the central conductor 56 by rotating the antenna motor 54 that is a driving unit.

  When the frequency of the microwave generated from the magnetron 51 is 2450 MHz, the wavelength of the microwave is about 122 mm, the length of the flat plate A61 is about 1/4 mm, and the length of the flat plate B62 is about 1/4 mm. It is about 1/2 of the wavelength.

  Therefore, the rotating antenna 60 according to the present embodiment has a characteristic that the electric field is concentrated on the tip of the flat plate A61 and the microwave is irradiated from the flat plate A61 side. Therefore, when the rotating antenna 60 is fixed, the object to be heated on the flat plate A61 side is strongly heated by irradiating many microwaves on the flat plate A61 side, and when the rotating antenna 60 is rotated, the entire heating chamber 2 is heated. It is possible to heat uniformly.

  As described above, the feature of this embodiment is that the six flat plates are evenly arranged radially, and one of them is a short flat plate. Further, the angle between the flat plates is 60 degrees, and there is almost no interference of microwaves at the tips of the flat plate A61 and the flat plate B62.

  Here, when the width of the flat plate is 30 mm or more, which is about 1/4 of the microwave wavelength, the microwave is transmitted also in the width direction of the flat plate (circumferential direction of the rotating antenna). Microwaves are less likely to be transmitted in the length direction (outer peripheral direction of the rotating antenna), and the microwaves are less likely to be irradiated outside the rotating antenna 60. Further, when the width of the flat plate is 15 mm or less, which is about 1/8 of the microwave wavelength, there is a high risk of sparking due to excessive concentration of the electric field. Therefore, when the microwave frequency is 2450 MHz, the width of the flat plate A61 and the flat plate B62 is appropriately about 20 mm as in this embodiment.

  Further, as in this embodiment, the length of the flat plate A61 is set to about 1/4 of the microwave wavelength, and the length of the flat plate B62 is set to about 1/2 of the microwave wavelength, so that the microwave is irradiated from the flat plate A61. It becomes easy.

  FIG. 4 shows the calculation result of the microwave absorption rate distribution of water when 285 ml of water is placed in a glass container having a diameter of 150 mm and a height of 75 mm and heated.

  The upper row is the result when a rotating antenna having a combination of three short pieces and three long pieces described in FIG. 2 of Patent Document 1 is employed, and the lower portion is a single flat plate A61 according to the present embodiment. It is a result at the time of using the rotating antenna 60 shown in FIG. 1 of the shape which combined 5 flat plate B62.

  As shown in the upper part of FIG. 4, when the number of the short pieces is 3, the distribution variation of the microwave absorption rate is small, and the microwave absorption rate repeatedly increases and decreases depending on the antenna angle. And it is difficult to heat a specific part intensively.

  On the other hand, in the rotating antenna 60 according to the present embodiment shown in the lower part of FIG. 4, the portion where the microwaves concentrate (the portion a surrounded by the dotted line) according to the rotation angle of the rotating antenna 60 rotates around the rotation center. Since the fluctuation of the overall microwave absorption rate is small at any angle, the microwave can be efficiently radiated, and when the rotating antenna 60 is fixed, the heated object on the flat plate A61 side is When the rotary antenna 60 is rotated intensively, the whole is heated uniformly.

  Therefore, the rotating antenna 60 according to the present embodiment can control the microwave distribution in the heating chamber 2 more easily than the shape in which three short pieces and three long pieces are combined as described in Patent Document 1. Easy to control the state.

  A weight sensor 31 is provided below the heating chamber 2 so as to be positioned below the table plate 21 and the table plate 21, and the weight of the food placed on the table plate 21 by the weight sensor 31 is determined. It is a structure that detects and heats food.

  Since three weight sensors 31 are installed in total, two on the left and right sides on the front side and one on the center on the rear side, it is also possible to detect the placement position in addition to the food weight on the table plate 21. .

  Therefore, the center of gravity position of the object to be heated placed on the table plate 21 is detected, and the antenna motor 54 as the driving unit is temporarily stopped in a state where the flat plate A61 side of the rotating antenna 60 is directed in the direction of the center of gravity. By doing so, it is possible to centrally heat the placement position of the object to be heated. Further, even when a plurality of objects to be heated are placed, it is possible to uniformly heat the objects to be heated by performing concentrated heating on the object to be heated that is heavier.

  In addition, in the conventional antenna shape with low directivity that emphasizes the reduction of heating unevenness, it was difficult to centrally heat the placement position of the object to be heated, but the antenna shape according to this embodiment is a conventional rotating antenna. Unlike the shape, the directivity is very high, and by stopping the rotating antenna 60, it is possible to locally heat the object to be heated. In addition, by rotating the rotating antenna 60, it is possible to move the central heating range, so that the whole can be heated uniformly.

  Moreover, it is also possible to heat the specific position of the heating chamber 2 intensively according to a user instruction. For example, when two foods with different temperatures are heated, the position of the food with the low initial temperature is indicated and the degree of heating of the food with the low temperature and the food with the high temperature is changed. It is possible to heat to temperature.

  In addition, even when food that you want to heat and food that you do not want to heat are mixed, the user indicates the location of the food that you want to heat, or by placing the food you want to heat in a predetermined position, It is also possible to intensively heat only the food that is desired to be heated, while hardly heating the food that is not desired to be heated.

  In addition, the rotating antenna 60 according to the present embodiment is easy to irradiate microwaves strongly in the direction of the flat plate A61. Therefore, in the heating chamber 2 having a shape having a different depth and width, it is easy to concentrate microwaves on a heated object near a side surface having a relatively long distance from the rotation center of the rotating antenna 60.

  Further, since the diameter of the rotating antenna 60 may be about 120 mm, which is substantially the same as the wavelength of the microwave, the rotating antenna 60 is smaller than the size of the bottom surface of the heating chamber 2, and the weight sensor 31 is provided around the rotating antenna 60. It is easy to arrange such parts.

  Further, by adopting a structure in which the hole is not provided in the rotating antenna 60, it is possible to manufacture at a lower cost than a conventional rotating antenna provided with a hole.

  Therefore, the rotating antenna 60 according to the present embodiment can reduce heating unevenness, improve heating efficiency, and improve local heating performance at low cost.

  The machine room 3 stores control means for controlling the heating means and the air blowing means, other heating means, and the like. Moreover, although the door 4 is arrange | positioned in the front opening direction of the heating chamber 2, the opening / closing direction of the door 4 may be horizontal, and the position and direction of the door 4 are not particularly defined.

  Further, the heating cooker 1 according to the present embodiment is provided with a flat heater 32 on the upper surface of the heating chamber 2, a hot air heater (not shown) on the rear surface of the heating chamber 2, and a magnetron 51 below the heating chamber 2 as heating means. ing. The flat heater 32 installed on the upper surface of the heating chamber 2 is a heater that generates heat over the entire surface, and is a heating means that heats food by radiation heating from above the food. The hot air heater installed on the back surface of the heating chamber 2 is provided with air blowing means in the vicinity thereof, and supplies food heated by forced convection heating by supplying air heated by the hot air heater into the heating chamber 2 as hot air. The magnetron 51 installed below the heating chamber 2 can heat the object to be heated by generating a microwave and supplying it into the heating chamber 2.

  The door 4 in front of the heating chamber 2 is provided with setting means (not shown). The user can instruct the cooking device 1 with the cooking menu, cooking temperature, and method by operating the setting means. Although the position of the setting means in the present embodiment is the door 4, the position of the setting means may be provided in a portion other than the door 4, and the position and operation method are not limited.

  Next, the cooking method according to the present embodiment will be described.

  First, when cooking one object to be heated, the door 4 of the heating cooker 1 is opened, the object to be heated is placed on the table plate 21 below the heating chamber 2, the door 4 is closed, and the setting means is used. The cooking device 1 is instructed to cook.

  Microwaves generated by the magnetron 51 from the start of cooking are transmitted through the waveguide 52 and transmitted from the coaxial circuit between the coupling hole 53 and the center conductor 56 into the heating chamber 2. The antenna motor 54 is driven with the start of cooking, and the dielectric shaft 55, the central conductor 56 connected thereto, and the rotating antenna 60 rotate.

  At the same time, the three weight sensors 31 arranged at the lower part of the table plate 21 detect the weight and position of the object to be heated placed on the table plate 21 and automatically set the heating time according to the weight of the object to be heated. To decide.

  When the rotating antenna 60 rotates and the flat plate B62 side faces the position of the object to be heated, if the driving of the antenna motor 54 is temporarily stopped, the rotation of the rotating antenna 60 stops, and the rotating antenna 60 strongly stops from the flat plate B62 side. Since microwaves are irradiated, the microwaves concentrate on the object to be heated, and the object to be heated is efficiently heated.

  Here, the temporary drive stop time is an arbitrary value, but if it is too long, local heating may occur in an unintended part in the heating chamber 2, so the stop time is about several seconds to several tens of seconds. After the time is over, the antenna motor 54 is driven again, and the rotating antenna 60 also rotates.

  Next, when the flat plate B62 side of the rotating antenna 60 faces the object to be heated, the antenna motor 54 is stopped again to stop the rotating antenna 60. By repeating this until the heating end time, the microwave can be concentrated on the object to be heated and the heating can be performed efficiently. In addition, when the center of gravity of the object to be heated is in the center of the table plate 21, heating is performed while the rotating antenna 60 is constantly rotated without stopping the antenna motor 54, and thus cooking without heating unevenness is possible.

  Similarly, when cooking two objects to be heated, the weight and position of the object to be heated are detected by the three weight sensors 31, and the flat plate B62 of the rotating antenna 60 is directed to a heavier object to be heated. The antenna motor 54 is stopped. As a result, it is possible to concentrate more microwaves on the object to be heated that is difficult to warm out of the two objects to be heated, so that the two objects to be heated can have a similar finish. Further, when the weights of the two objects to be heated are approximately the same, the center of gravity is at the center, so that both can be heated evenly.

  In addition, when heating one large object to be heated, the center of gravity position of the object to be heated is at the center of the table plate 21, so that the rotating antenna 60 can be constantly rotated and heated without unevenness.

  Here, if the setting means has a function of setting the heating position, the user instructs the heating position by the setting means, whereby the rotating antenna 60 is stopped at the indicated position, and the position indicated by the user is concentrated. It is also possible to heat a part of a large object to be heated.

  In this way, by using the rotating antenna 60 according to the present embodiment to detect the weight and position of the object to be heated and control the cooking, the position of the object on the table plate 21 can be controlled regardless of the number of objects to be heated. Even if a heated object is placed, the microwaves are concentrated at that position, so that heating can be efficiently performed regardless of the placement position and weight.

  Further, by changing the shape of the rotating antenna 60 from a shape in which flat plates are radially arranged with a diameter of 120 mm to a shape in which the length of one flat plate is shortened, the directivity of microwave irradiation with a frequency of 2450 MHz that can be irradiated by the rotating antenna 60 is strengthened. When the rotating antenna 60 is fixed, the direction with strong directivity is intensively heated, and when the rotating antenna 60 is rotated, uneven heating can be reduced while efficiently irradiating microwaves.

  Therefore, in the cooking device of the present embodiment, local heating and uniform heating in the heating chamber can be freely controlled, heating unevenness can be reduced, and heating efficiency can be improved.

DESCRIPTION OF SYMBOLS 1 Heating cooker 2 Heating chamber 3 Machine room 21 Table plate 31 Weight sensor 51 Magnetron 52 Waveguide 53 Coupling hole 55 Dielectric shaft 56 Center conductor 60 Rotating antenna 61 Flat plate A
62 Flat plate B

Claims (4)

A main body of a heating cooker, a heating chamber disposed in the main body for heating food, a magnetron disposed under the heating chamber for generating microwaves for heating the food, and a microwave generated in the magnetron A propagating waveguide, a coupling hole provided between the waveguide and the heating chamber, a central conductor penetrating the coupling hole, a dielectric shaft coupled to the central conductor, and the dielectric A drive unit for driving the body axis, and a rotating antenna composed of a conductive plate electrically connected to the central conductor;
The rotating antenna has six flat plates arranged radially from the rotation center at intervals of 60 degrees, and the length from the rotation center of one of the six flat plates is the length from the rotation center of the other flat plate. A cooking device characterized by being shorter than that.   When one flat plate having a short length from the rotation center of the rotating antenna is a flat plate A and the other flat plate is a flat plate B, the length from the rotation center of the flat plate A is substantially the same as ¼ of the microwave wavelength. The heating cooker according to claim 1, wherein the length from the rotation center of the flat plate B is substantially the same as ½ of the microwave wavelength.   The cooking device according to any one of claims 1 to 2, wherein a width of the flat plate A and the flat plate B constituting the rotating antenna is ¼ to ８ of a microwave wavelength. .   A plurality of weight detecting means for detecting the weight and position of the food are provided at the lower part of the heating chamber, and when the flat plate A of the rotating antenna is located on the center of gravity side of the object to be heated, the driving of the rotating antenna is temporarily performed The cooking device according to any one of claims 1 to 3, wherein the cooking device is stopped.

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