JP2005273977A - Heating cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating cooker capable of easily detecting the heating state of a food by its high visibility by forming a see-through window having high opening ratio, manufacturable at low cost, and having less surface irregularities. <P>SOLUTION: This heating cooker comprises a heating chamber 7 storing foods, a door openable to retrieve and store the foods from and into the heating chamber 7 and having a see-through window 3 for observing the foods in the heating chamber 7, and a microwave oscillator feeding a microwave energy to the heating chamber 7. The see-through window 3 formed of at least a window frame 22, an expand metal 32 fixed to the window frame 22, and glass panes 30 and 31 disposed on both sides of the expand metal 32 is installed at the door 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a heating chamber for storing food, a door that is openable and closable for putting food in and out of the heating chamber, and having a transparent window for viewing food in the heating chamber, and microwave energy in the heating chamber. The present invention relates to improvement of a door in a heating cooker provided with a high-frequency oscillator to be supplied.

  Conventionally, in a cooking device, a see-through window is provided in a part of the door so that the heating state of food in the heating chamber can be observed. This see-through window has a small round hole of about φ1 to 1.5 mm in a thin metal plate of about 0.5 to 1 mm so that microwave energy in the heating chamber does not leak outside through the see-through window of the door during food heating. Punching metal with a lot of holes is generally used.

  This punching metal has small holes below the cut-off wavelength, which is sufficiently smaller than the wavelength used, and observes the heating status of food through the small holes without receiving leakage microwave energy from the viewing window. Can do.

  In addition, the higher the aperture ratio of the transparent window, the easier it is to observe the food state in the cooking process even with microwave heating or heater heating such as an oven. Use a wire mesh knitted with thin metal wires as a transparent window instead of punching metal. Examples (Patent Document 1), and examples (Patent Document 2) in which a transparent conductive film having a thickness of several μm is formed on a glass plate.

Japanese Patent Laid-Open No. 2001-237061

JP-A-6-68975

  In conventional see-through windows made of punched metal, the width of the metal part between the small-diameter holes is large even though the aperture ratio is 50% or more, and this metal part becomes an obstacle when food is observed through the see-through window. There is a problem that it is difficult to see.

  Moreover, since the plate | board thickness of a punching metal is thick, even if it is easy to see from the front, visibility deteriorates depending on the angle which observes the foodstuff of a heating chamber from a transparent window.

  Further, even in Patent Document 1, there is a problem similar to that of the conventional punching metal due to the wire diameter width of the metal wire.

  On the other hand, when the punching metal is formed into a thin metal, a high manufacturing technique is required, and the manufacturing cost is high, and deformation is likely to occur and handling is difficult.

  In addition, when a wire mesh is configured with a wire having a small diameter, the cost is higher than that of a machined product, and the flexibility is very high, and wrinkles and sagging are likely to occur during mounting.

  Furthermore, the thermal expansion and contraction of the metal wire is repeated with the temperature change of the heating chamber, so that surface wrinkles and sagging are likely to occur, and it is difficult to obtain stable visibility.

  Further, in a wire mesh knitted with metal strands, the contact state of the wires at the intersection greatly affects the performance.

  Moreover, in the thing using the electroconductive film | membrane with high transparency shown in patent document 2, although visibility is excellent compared with the see-through window comprised with the said punching metal or a metal net, it is necessary to make a thin film into glass film formation. In addition, it takes too much time and labor to manufacture, and the cost becomes very high.

  In addition, care is required so as not to damage the thin film formed on the glass, and it is time-consuming and labor-intensive in quality control, such as requiring confirmation of the presence or absence of scratches, resulting in an increase in cost.

  The present invention has been made to solve at least one of the above problems.

  According to claim 1 of the present invention, a heating chamber for storing food, a door that is openable and closable for putting the food in and out of the heating chamber, and has a transparent window for viewing food in the heating chamber, and the heating chamber A high-frequency oscillator for supplying microwave energy to the door, and the door is composed of a window frame, an expanded metal whose periphery is fixed to the window frame, and a glass plate arranged with both sides of the expanded metal sandwiched between them. is there.

  According to a second aspect of the present invention, the thickness of the expanded metal is 0.05 mm to 0.3 mm, and the aperture ratio is 50% or more.

  According to a third aspect of the present invention, the width of the cut in the opening of the expanded metal (center distance in the long direction) is 0.5 mm to 1 mm.

  Furthermore, in claim 4, the narrowest angle of the opening after tensile processing of the expanded metal is 45 degrees to 90 degrees.

  According to a fifth aspect of the present invention, at least one side of the outer periphery of the expanded metal is constituted by a flat edge having no opening, and the expanded metal is fixed to the window frame by the edge.

  Furthermore, according to Claim 6, the said glass plate arrange | positioned in the front of a heating cooker is made into half mirror glass.

  According to the first aspect of the present invention, a see-through window having a high aperture ratio, a low manufacturing cost, and a small number of surface irregularities can be configured. Can provide cooker.

  Further, according to the second aspect, each opening of the expanded metal can be configured with a very small area, and accordingly, a high aperture ratio can be realized.

  Moreover, according to claim 3, it is possible to have high microwave energy blocking performance and visibility.

  Furthermore, according to claim 4, a see-through window having a higher aperture ratio and higher visibility can be easily formed.

  According to the fifth aspect, the window frame and the expanded metal can be easily attached, and the workability of the door assembly can be improved.

  Furthermore, according to Claim 6, according to the light of the interior lamp which lights at the time of foodstuff heating, the see-through window which becomes highly visible only at the time of cooking can be comprised.

  FIG. 1 shows a heating cooker according to an embodiment of the present invention, which is a turntableless type microwave oven in which food (not shown) is placed on a table 40 on the bottom of the heating chamber 7 for cooking.

  Note that the cooking device of the present invention can be applied to a turntable type microwave oven in which food is placed on a turntable in a heating chamber for cooking and a single-function microwave oven only for microwave heating.

  In the figure, the heating cooker is provided with a metal conductor heating chamber 7 in which food is stored inside the cabinet 10 for cooking, and an openable door 2 for taking in and out the food is provided in front of the heating chamber 7. It is provided to be movable.

  In addition, an antenna is provided below the table 40 on the bottom surface of the heating chamber 7, and a motor (not shown) is installed below so as to rotate during microwave heating of the food.

  A magnetron (not shown), which is a high-frequency generator for microwave heating of food, is disposed in the gap between the heating chamber 7 and the cabinet 10, and the microwave energy is heated via a waveguide (not shown). 7 is emitted.

  Here, the connection portion between the waveguide and the heating chamber 7, that is, the supply port of the microwave energy may be below the table 40 on the bottom surface of the heating chamber, or on the side surface or top surface of the heating chamber.

  Further, the door 2 of this embodiment can be smoothly opened and closed by the door arms 11 provided on the left and right outer sides of the heating chamber 7 so as to open vertically with respect to the heating chamber 7.

  In addition, this invention is easily applicable also to the heating cooker whose door opens sideways.

  The door 2 is composed of a metal conductor window frame 22 housed in a door cover 20 and a see-through window 3 disposed in the center thereof, and the inside of the heating chamber 7 is observed from the outside through the see-through window 3. Be able to.

  Further, when the door 2 is closed, a part of the window frame 22 is in close contact with the front portion of the heating chamber 7 so that the microwave energy in the heating chamber 7 does not leak to the outside during the heating of the food.

  Further, the gap between the window frame 22 and the see-through window 3 is filled with a seal member 25, so that the steam of the food cooked in the heating chamber 7 and scattered debris do not enter the inside of the see-through window 3.

  FIG. 2 is a perspective sectional view of the door 2 in which the portion X in FIG. 1 is enlarged.

  The see-through window 3 is composed of an expanded metal 32 fixed to the window frame 22 and two glass plates 30 and 31 provided with the expanded metal 32 interposed therebetween.

  Therefore, the glass plate 31 that becomes the heating chamber 7 side when the door 2 is closed has a role of constituting a part of the heating chamber 7.

  Since the door 2 is closed when the food in the heating chamber 7 is cooked, the glass plate 31 is also greatly related to the visibility through the transparent window 3.

  Therefore, it is desirable that the glass plate 31 has a high aperture ratio and is transparent.

  Further, the glass plate 31 becomes a wall surface of the heating chamber 7 and is made of a material having high heat resistance because water vapor generated from the food during the heating of the food or scattered debris of the food adheres.

  On the other hand, the glass plate 30 of the door 2 arranged on the front surface of the cooking device is also related to the visibility of the see-through window 3 and is preferably transparent with a high aperture ratio.

  Further, the glass plate 30 may be made of the same material as the glass plate 31 because the temperature rise due to food heating and the adhesion of dirt due to food are small compared to the glass plate 31 on the heating chamber side, but it is a heat resistant material lower than that. It may be configured.

  Therefore, since the glass plate 30 is less limited by temperature and dirt, it has a wider selection range of glass types than the inner glass plate 31. For example, colored glass, half-mirror glass, heat ray reflective glass, etc. are arranged to improve the appearance. You can select glass with improved design and heat insulation performance.

  Here, if the glass plate 30 is a half mirror, the design of the kitchen can be improved when the cooking device is not used, and only when the food is placed in the heating chamber 7 and cooked, the heating chamber The inside of the heating chamber 7 can be observed only when the interior lamp (not shown) 7 is turned on.

  The see-through window 2 is constituted by an expanded metal 32 provided between the glass plates 30 and 31.

  FIG. 3 is an enlarged view of a Y portion in FIG. 2, and is a perspective view of the expanded metal 32.

  The expanded metal 32 is formed by cutting a zigzag pattern on a metal plate and then drawing it into a rhombus or turtle shell-shaped mesh.

  The rhombus may be further pulled into a square.

  Furthermore, it is more desirable that the narrower angle θ be 45 degrees or more and 90 degrees or less in consideration of the safety of the shield.

  The opening ratio by the expanded metal 32 is adjusted by the width LW of the cut, the pulling width SW of the cut, and the pitch W of the cut.

  Here, in terms of processing design, it is desirable that the cut pitch W is a value close to the thickness t of the metal plate. When t increases, the tensile width SW becomes difficult to obtain.

  It is important that the see-through window 3 of the heating cooker has high electromagnetic shielding performance (attenuation property) without leakage of microwave energy and a high aperture ratio.

  For example, the opening ratio of the expanded metal should be secured 50% or more, and the attenuation rate of the microwave energy should be secured 45 dB or more, and more preferably, the attenuation rate should be 50 dB or more.

  Here, for example, in order to maintain high attenuation with respect to microwave energy, if the dimension of the expanded metal is formed with a plate thickness t = 0.05 mm to 0.3 mm and the cut width LW is 1 mm or less, the aperture ratio is increased. The see-through window 3 with high visibility at 50% or more can be realized.

  In consideration of workability, the LW is more preferably about 0.5 mm to 1.0 mm.

  Further, since the plate thickness is not thin, handling and workability are also improved.

  Further, even when the transparent window 3 is viewed from an oblique direction, the inside of the heating chamber 7 becomes easier to observe as the plate thickness t is thinner.

  Further, since the expanded metal 32 is formed by being plastically deformed into a flat shape, it is possible to maintain a higher strength than a punching metal having the same plate thickness, so that deformation such as wrinkles and sagging is less likely to occur in the transparent window 3. High visibility can be obtained stably.

  Further, the surface of the expanded metal 32 after processing is glossy due to the metal surface, and when the glossy surface is attached to the transparent window 3 as it is, the window shines and it is difficult to observe the situation inside the heating chamber 7.

  Therefore, when the inside of the heating chamber 7 is observed from the transparent window 3 through the expanded metal 32 by darkening (for example, black) the surface of the expanded metal 32 by paint or surface treatment, the gloss is reduced and the expanded metal 32 is reduced. Therefore, the inside of the heating chamber 7 can be more easily observed.

  The outer peripheral portion 33 of the expanded metal 32 is fixed so as to be electrically connected to the window frame 22.

  Here, as a fixing method, for example, the outer peripheral portion 33 of the expanded metal 32 and the window frame 22 may be directly welded, or the expanded metal 32 may be fixed by being sandwiched between the window frame 22 and another metal frame.

  Moreover, if the part which does not carry out an expansion process is provided in at least one side of the outer peripheral part 33 of the expanded metal 32, since the contact part of the window frame 22 and the expanded metal 32 can be comprised in a wide surface, both can be fixed easily. .

  FIG. 4 shows an example thereof, in which flat portions 32b that are not processed are provided on both sides of the expanded metal 32a. For example, when the left and right directions are pulled, the flat portions 32b can be easily left and processed.

  Moreover, you may make it the structure pulled alternately up and down, right and left so that the expanded metal 32a may be shape | molded only in the center.

  Further, if the fixing pitch such as welding is ¼ or less of the wavelength of the microwave, for example, 10 to 30 mm, leakage of radio waves from the outer peripheral portion 33 can be sufficiently prevented.

  Further, choke grooves 22a and 22b are formed on the outer periphery of the window frame. When a gap is generated in the front portion of the door 2 and the heating chamber 7, microwave energy leaks to the outside from the gap between the cabinet 10 and the door 2. It is electrically attenuated so as not to occur.

  The opening portions of the choke grooves 22a and 22b are covered with a choke cover 21 made of a low dielectric loss material so that foreign matter from the outside does not enter.

  In the above configuration, the operation of the heating cooker of the present embodiment will be described.

  When the food is heated by microwaves, the door 2 is opened, the food is placed in the heating chamber 7, and after the door 2 is closed, cooking is started.

  Simultaneously with the start of heating, the interior lamp of the heating chamber 7 is turned on, and microwave energy is guided by the magnetron through the waveguide, for example, from below the table of the heating chamber into the heating chamber 7.

  The food in the heating chamber 7 is heated, and its progress can be observed through the see-through window 3 provided in the door 2.

  As shown in FIG. 2, the expanded metal 32 disposed between the glass plates 30 and 31 of the transparent window 3 is safe without leakage of microwave energy to the outside, and the expanded metal having a high aperture ratio. This is because the heating chamber can be seen clearly.

  Further, when food is heated on a grill or oven, the baked color on the surface of the food can be more easily observed, and the food can be taken out by checking the optimum baking for the food.

  As described above, the visibility window 3 of the present invention can improve the visibility compared to the prior art, so that any food heating method can be effectively used and an easy-to-use cooking device can be provided.

  Moreover, if the expanded metal 32 used for the fluoroscopic window 3 is provided between the interior lamp and the heating chamber 7, the heating chamber 7 can be illuminated more brightly, and high visibility can be realized in combination with the fluoroscopic window 3 of the present invention.

It is a perspective view of the heating cooker in one Example of this invention. It is a perspective sectional view of the door which expanded X section of Drawing 1. It is the perspective view which expanded the Y section of FIG. It is a top view of the other expanded metal board in one Example of this invention.

Explanation of symbols

2 door 3 see-through window 7 heating chamber 10 cabinet 11 door arm 22 window frame 25 sealing member 30 glass plate 32 expanded metal

Claims (6)

A heating chamber for storing food, a door that is openable and closable for putting the food in and out of the heating chamber, and having a transparent window for viewing food in the heating chamber, and a high frequency that supplies microwave energy to the heating chamber A heating cooker comprising an oscillator, wherein the door is composed of a window frame, an expanded metal whose periphery is fixed to the window frame, and a glass plate disposed on both sides of the expanded metal. The cooker according to claim 1, wherein a thickness of the expanded metal is 0.05 mm to 0.3 mm, and an opening ratio is 50% or more. The cooking device according to claim 1 or 2, wherein a width of the cut of the opening of the expanded metal (center distance in the long direction) is 0.5 mm to 1 mm. The cooking device according to any one of claims 1 to 3, wherein the narrowest angle of the opening after the expansion processing of the expanded metal is 45 degrees to 90 degrees. The cooking device according to any one of claims 1 to 4, wherein at least one side of the outer periphery of the expanded metal is constituted by a flat edge having no opening, and the expanded metal is fixed to the window frame by the edge. 6. The cooking device according to claim 1, wherein at least one of the glass plates is a half mirror glass.

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