KR100777311B1 - Microwave heating device - Google Patents

Abstract

The present invention relates to a heating device configured to heat an object using microwaves. The heating apparatus according to the present invention includes a case in which a heating chamber to which microwaves are irradiated is formed; A door for opening and closing the heating chamber; An elongated groove formed along an inner edge of the door and having an inner wall adjacent to the heating chamber when the door is closed; A partition plate extending from a center of the bottom of the groove to define an inner space of the groove; At least one protrusion extending from the door and the partition plate to partially cover the inlet of the groove and attenuating the microwave to prevent leakage of the microwave; And an auxiliary groove formed concave in the inner wall to expand the size of the inner space of the groove adjacent to the inner wall to improve the attenuation characteristic of the microwave.

According to the present invention, it is possible to effectively shield microwaves of a wide frequency band and to effectively cope with pull leakage by simply changing the structure of the filter forming the auxiliary grooves on the inner wall of the grooves, and to provide a gap between the door and the front panel. It can be effectively applied to large products, especially those with glass attached to the inner surface of the door.

Heating device, microwave, filter, shielding, groove, LC circuit, resonance, frequency band

Description

Heating device using microwaves {Microwave heating device}

1 is a perspective view showing a heating apparatus using a microwave according to the present invention;

2 is a partial perspective view showing a microwave shielding filter of the heating device of FIG. 2;

3 is a cross-sectional view of the shielding filter of FIG. 3;

4 is a graph showing microwave attenuation characteristics according to the depth of the auxiliary groove of FIG. 3; And

5 is a graph showing a frequency bandwidth to obtain a sufficient amount of attenuation depending on the depth of the auxiliary groove.

Explanation of symbols on the main parts of the drawings

100: case 110: heating chamber

120: front panel 140: microwave supply device

150: heater 200: door

250: glass 300: filter

310: groove 320: partition plate

325, 335: protrusion 350: auxiliary groove

The present invention relates to a heating device, and more particularly to a heating device configured to heat an object using microwaves.

A typical electric device configured to heat an object using microwaves is a microwave oven. A typical microwave oven includes a heating chamber formed inside the case, a door provided at the front of the microwave oven to open and close the front surface of the heating chamber, a magnetron that oscillates microwaves, and guide the microwaves generated by the magnetrons into the heating chamber. It consists of a waveguide to irradiate. Microwaves irradiated into the heating chamber by the magnetron and the waveguide cause vibration of water molecules of an object located in the heating chamber, for example, food, and the heating object is heated by the kinetic energy of the vibrating water molecules. .

In order to allow a user to look into the heating chamber, the door is generally provided with a see-through window, and the see-through window is provided with a screen for preventing leakage of microwaves. The screen has a plurality of holes smaller than a predetermined size, for example less than one quarter of the wavelength of the microwave, so that the user can look inside the heating chamber through the small holes of the porous screen mounted to the viewing window. have.

Meanwhile, when the heating object is heated using the microwave, the microwave may leak through a gap between the door and the case of the heating device. Accordingly, a filter for preventing leakage of microwaves irradiated into the heating chamber is provided around the door. The filter typically uses an LC circuit system to prevent leakage of microwaves between the door and the front panel of the case.

A typical filter is, for example, a groove formed along an edge of an inner surface of the door, and bent at an upper end of the side wall of the groove adjacent to the circumferential surface of the door to partially cover the inlet of the groove and the cavity inside the groove. It comprises a plurality of protrusions to form.

Surfaces surrounding the front panel and the cavity, that is, sidewalls and bottom of the groove, and the protrusions form a line, the line having a kind of inductance "L" which prevents the progress of high frequency. Is formed. In addition, a kind of capacitance "C" smoothing high frequency propagation between two lines separated from each other, for example, between the front panel and the protrusion, between the protrusions, and between the end of the protrusion and the side wall of the groove. capacitance "C") is formed. Therefore, the microwaves incident on the filter are electrically resonated and attenuated by a kind of LC circuit formed by the structural characteristics of the filter, thereby suppressing the leakage of the microwaves through the gap between the case and the door.

On the other hand, in recent years, the glass is mounted on the inner surface of the door in order to improve the cleaning of the inner surface of the door, in this case, the gap between the door and the front panel becomes larger by the thickness of the glass. Therefore, the conventional filter structure alone does not effectively cope with microwave leakage of the heating device having a large gap between the door and the front panel.

As described above, the filter for shielding the microwave by using an LC circuit can show normal shielding performance when the door is normally closed, but when the door is slightly pulled, the gap between the door and the front panel is increased. The leakage of microwaves through the larger gap increases. This is commonly referred to as "pull leakage," and it is difficult to effectively cope with such pull leakage with a conventional filter structure.

In order to effectively reduce the microwave leakage of the heating device with a large gap between the door and the front panel, and to effectively cope with the "pull leakage," the plurality of LC circuits are arranged along the traveling direction of the leaked microwave. You need a filter with a built-in structure. Such a filter resonates the leaking microwaves several times to minimize the amount of leakage of the microwaves.

However, the size of the filter having a structure in which several LC circuits are arranged along the traveling direction of the leaked microwaves is inevitably large. By the way, since the space in which the filter can be installed is generally limited to the area between the periphery of the see-through window and the perimeter of the door, the number of LC circuits of the filter cannot be sufficiently increased. Thus, the frequency bandwidth at which a filter with several LC circuits can effectively shield microwave leakage in a heating device with a large gap between the door and the front panel and effectively cope with the pull leakage is limited.

The present invention has been made to solve the above problems, and an object thereof is to improve the structure of the microwave shielding filter so as to effectively shield microwaves of a wide frequency band.

Another object of the present invention is to effectively shield microwaves of a wide frequency band by making minor improvements without significantly altering the structure of the door or the microwave shielding filter itself.

In one embodiment of the present invention for achieving the above object, a case in which a heating chamber to which microwaves are irradiated is formed; A door for opening and closing the heating chamber; An elongated groove formed along an inner edge of the door and having an inner wall adjacent to the heating chamber when the door is closed; A partition plate extending from a center of the bottom of the groove to define an inner space of the groove; At least one protrusion extending from the door and the partition plate to partially cover the inlet of the groove and attenuating the microwave to prevent leakage of the microwave; And it provides a heating device using a microwave formed concave in the inner wall and comprises an auxiliary groove to expand the size of the inner space of the groove adjacent to the inner wall to improve the attenuation characteristics of the microwave.

Here, the upper end of the inner wall is preferably formed continuously along the longitudinal direction of the auxiliary groove to cover the upper portion of the auxiliary groove. The upper end of the inner wall and the protrusion are preferably disposed to face each other. On the other hand, the heating apparatus according to the present invention may be made by further comprising a glass attached to the inner surface of the door to cover the groove.

DETAILED DESCRIPTION Hereinafter, embodiments of the present invention in which the above object can be specifically realized are described with reference to the accompanying drawings. In describing the embodiments, the same names and symbols are used for the same components, and additional description thereof will be omitted below.

As shown in FIG. 1, a heating chamber 110 in which a heating object, for example, foods, is accommodated is provided in the case 100 that forms the exterior of the heating apparatus. An inlet for accessing the inside of the heating chamber 110 is formed on one surface, for example, the heating chamber 110, and the front of the case 100 surrounds the inlet of the heating chamber 110. The front panel 120 is provided.

The outer surface of the case 100 is provided with a control panel 130 for controlling the heating device, the control panel 130 may be located above the front of the case 100, for example. The control panel 130 is not limited to the position shown in FIG. 1 and may be disposed at another position in consideration of an installation position of the heating device and a user's convenience.

Between the case 100 and the heating chamber 110, a microwave supply device 140 for irradiating microwaves into the heating chamber 110 is provided. The microwave supply device 140 includes, for example, a magnetron 141 for generating microwaves, and a waveguide 143 for guiding and irradiating the microwaves generated by the magnetron 141 to the heating chamber 110. Can be done. Here, the magnetron 141 oscillates microwaves in the frequency band of 2.4 GHz to 2.5 GHz, preferably 2.45 GHz.

Microwaves oscillated by the magnetron 141 are irradiated into the heating chamber 110 through the waveguide 143. The microwave may be irradiated into the heating chamber 110 in a simple pattern. In this case, the heating object located in the heating chamber 110 may not be evenly heated.

In order to compensate for this, a rotating tray (not shown) may be provided at the bottom of the heating chamber 110. Then, the heating object is placed on the tray is rotated can be more evenly heated. Furthermore, a stirrer fan may be further provided in the waveguide 143 or the heating chamber 110 to scatter microwaves to be irradiated. Then, the microwave is irradiated into the heating chamber 110 in a more complex and various patterns, it is possible to evenly heat the heating object.

The microwave supply device 140 is not limited to the structure described above, and any other modification or technique currently available that can be irradiated into the heating chamber 110 after generating the microwave may be employed.

The microwave irradiated into the heating chamber 110 vibrates water molecules included in the heating object to heat the heating object. Such a heating method alone is difficult to provide an optimal cooking service for each of the various types of food. Therefore, the heating apparatus according to the present invention may not only provide an optimal cooking service for each of various kinds of foods but also be further provided with additional heating means for increasing the types of cookable dishes.

An example of the additional heating means is a heat source for providing radiant heat to the heating chamber 110, for example a heater 150. 1 illustrates an example in which the heater 150 is disposed on the ceiling side of the heating chamber 110, but is not limited thereto. As another example, the heater 150 may be selectively provided on the side surface, the rear surface, or the bottom surface of the heating chamber 110. When additional heat sources providing radiant heat are provided, not only can additional cooking services such as baking and confectionery baking be provided, but also optimum cooking service can be provided by appropriately combining the supply of microwave and the amount and time of radiant heat. It may be provided.

A door 200 for opening and closing the inlet of the heating chamber 110 is mounted to the case 100 by the hinge assembly 101. FIG. 1 shows an example in which the door 200 is configured to open and close while rotating downwardly about a hinge assembly 101 fixed to a lower side of the case 100. However, the position of the hinge assembly 101 and the rotation direction of the door 200 may be changed in consideration of the user's convenience. For example, the hinge assembly 101 may be fixed to the side surface of the case 100 and the door 200 may be configured to be opened or closed while rotating the door assembly 200 in the left and right directions with respect to the hinge assembly 101.

As shown in FIG. 1, the door 200 may be provided with a viewing window so that a user may view the inside of the heating chamber 110. The see-through window is formed in the center of the door 200, and a porous screen (not shown) is installed in the see-through window so that microwaves irradiated into the heating chamber 110 do not leak to the outside through the see-through window. Therefore, the user may look inside the heating chamber 110 even during the heating of the heating object through the plurality of holes formed in the screen.

On the other hand, even when the door 200 is closed, the microwaves irradiated into the heating chamber 110 leak to the outside through the gap between the door 200 and the case 100, that is, the front panel 120. Can be. Therefore, the heating apparatus according to the present invention is provided with a filter 300 for suppressing the leakage of the microwaves.

The filter 300 is disposed to surround the inlet of the heating chamber 110 when the door 200 closes the heating chamber 110, and the microwaves are electrically resonated and attenuated by using an LC circuit. Prevent the leakage of microwaves. 2 and 3, a filter 300 according to the present invention is shown. Hereinafter, the filter 300 will be described in more detail with reference to these drawings.

The filter 300 is provided with an elongated groove 310 formed along the inner edge of the door 200. The groove 310 faces the front panel with a predetermined gap therebetween when the door 200 is closed. The groove 310 has an inner wall 315 and an outer wall 330. The inner wall 315 is disposed adjacent to the heating chamber 110 when the door 200 is closed, and the outer wall 330 ) Is disposed opposite the inner wall 315. The outer wall 330 of the groove 310 may form a circumferential surface of the door 200.

A plurality of protrusions 335 are formed at a portion of the door 200, for example, at an upper end of the outer wall 330 as shown in FIGS. 2 and 3. The protrusion 335 extends from the top of the outer wall 330 of the groove 310 toward the inner wall 315 of the groove 310 to partially cover the entrance of the groove 310. As shown in FIG. 2, the protrusions 335 are disposed at equal intervals along the length direction of the groove 310, and there are slots between two adjacent protrusions 335. However, it is not limited thereto. As another example, the protrusion 335 may be continuously formed along the longitudinal direction of the groove 310, although not illustrated.

The inner wall 315 of the groove 310 is formed with a concave auxiliary groove 350 as shown in FIGS. 2 and 3. The auxiliary groove 350 is recessed toward the center of the door 200 to expand the size of the inner space of the groove 310, and the upper end 340 of the inner wall 315 is the upper portion of the auxiliary groove 350. Will be submitted. The upper end 340 of the inner wall 315 is continuously formed along the longitudinal direction of the auxiliary groove 350, for example, as shown in FIG. As another example, the upper end 340 of the inner wall 315 may be discontinuously formed along the longitudinal direction, such as the protrusion 335, although not shown. Meanwhile, the upper end 340 of the inner wall 315 and the protrusion 335 are disposed to face each other as shown in FIGS. 2 and 3.

Meanwhile, glass may be attached to the inner surface of the door 200 as shown in FIGS. 2 and 3. The glass 250 forms an inner surface of the door 200 and covers the viewing window and the filter 300. Therefore, the glass 250 prevents the contaminants generated in the heating chamber 110 from accumulating in the filter 300, thereby improving the cleanability of the door 200. The glass 250 provided as described above is supported by the top 340 and the protrusion 335 of the door 200.

As shown in FIGS. 2 and 3, the filter 300 may further include a partition plate 320 for dividing the internal space of the groove 310 into two independent spaces. The partition plate 320 extends toward the inlet of the groove 310 at the center of the bottom of the groove 310 to divide the internal space of the groove 310 into two. At the upper end of the partition plate 320, the protrusion 325 may extend toward the upper end 340 of the inner wall 315. As shown in FIG. 2, a plurality of protrusions 325 are disposed at equal intervals along the length direction of the groove 310, and there are slots between two adjacent protrusions 325.

As described above, the partition plate 320 extends from the center of the bottom of the groove 310 to contact the inner space of the groove 310 with the inner wall 315 and the outer wall 330. ) Into a second space (S2) in contact with it. However, since the auxiliary groove 350 is formed in the inner wall 315, the first space S1 is larger than the second space S2 as shown in FIGS. 2 and 3.

Meanwhile, when the door 200 is closed, the top 340 and the protrusions 325 and 335 of the inner wall 315 face the front panel 120 of the case 100 with a predetermined gap therebetween. Microwaves irradiated into the heating chamber 110 travel toward the outside of the heating device through the gap. At this time, the end of the upper end 340 of the inner wall 315 serves as a kind of barrier (impedance) of infinite impedance. Thus, some microwaves at the top 340 of the inner wall 315 are reflected by the barrier.

The remaining microwaves are internal space of the groove 310, more specifically, the first space through the upper end 340 of the inner wall 315 and the entrance of the groove 310 not covered by the protrusion 325. It enters into S1. Here, since the size of the first space S1 is large because of the auxiliary groove 350, more microwaves are incident to the first space S1.

A kind of inductance "L" is formed on the inner wall 315 and the bottom surface of the groove 310, the partition plate 320, and the protrusion 325. And between the top 340 of the inner wall 315 and the front panel 120, between the protrusion 325 and the front panel 120, and the top 340 and the protrusion of the inner wall 315. Between 325, a kind of capacitance " C " for smoothly advancing high frequency components is formed. Therefore, a large amount of microwaves incident to the first space S1 are resonated and attenuated by the LC circuit formed by the structural characteristics of the filter 300.

Microwaves not incident to the first space S1 and microwaves not attenuated in the first space S1 are incident to the second space S2. Then, the resonance and attenuation are performed by the same principle as above.

On the other hand, the auxiliary groove 350 formed in the inner wall 315 of the groove 310 to extend the size of the first space (S1) is to induce a larger amount of microwaves into the first space (S1). see. This was indirectly demonstrated by experiments performed with different depths of the auxiliary grooves 350. This will be described in more detail with reference to FIGS. 3 and 4.

4 is a graph showing the microwave attenuation characteristics according to the depth of the auxiliary groove. 4 is a graph showing microwave attenuation characteristics when the depth of the auxiliary groove 350 is shallow in FIG. 3, and "B" in FIG. 4 is the depth of the auxiliary groove 350 in FIG. 3. Is a graph showing the microwave attenuation characteristics at deep "B". As shown in FIG. 4, the microwaves are attenuated more in the first space S1 than in the second space S2. And, the appropriate amount of attenuation "c" was obtained in a wider frequency band when the depth of the auxiliary groove 350 is deep. This means that a deeper depth of the auxiliary groove 350 can attenuate microwaves in a wider frequency band by an appropriate amount of attenuation "c".

In order to verify the experimental results of FIG. 4, the inventors experimented after setting the depth of the auxiliary groove 350 in various ways, and obtained the graph of FIG. 5 through experiments. As shown in the graph of FIG. 5, the frequency bandwidth for obtaining an appropriate amount of attenuation was found to be generally proportional to the depth of the auxiliary groove 350. Therefore, it is preferable that the depth of the auxiliary groove 350 be formed as deep as the structure of the door 200 allows.

The ability to obtain an adequate amount of attenuation over a wide frequency bandwidth can not only effectively cope with pull leakage, but also can be effectively applied to products with a large gap between the door and the front panel, especially those with glass attached to the inner surface of the door. It means that there is.

Although some embodiments have been described above by way of example, it will be apparent to those skilled in the art that the present invention may be embodied in many other forms without departing from the spirit and scope thereof. Accordingly, the described embodiments are to be considered as illustrative and not restrictive, and all embodiments within the scope of the appended claims and their equivalents are included within the scope of the present invention.

As described above, according to the present invention, there is an effect of effectively shielding microwaves in a wide frequency band by simply changing the structure of the filter forming the auxiliary grooves on the inner wall of the grooves.

In addition, the present invention can effectively cope with pull leakage, and can be effectively applied to a product having a large gap between the door and the front panel, in particular, a product having glass attached to the inner surface of the door.

Claims (5)

A case in which a heating chamber to which microwaves are irradiated is formed; A door for opening and closing the heating chamber; An elongated groove formed along an inner edge of the door and having an inner wall adjacent to the heating chamber when the door is closed; A partition plate extending from a center of the bottom of the groove to define an inner space of the groove; At least one protrusion extending from the door and the partition plate to partially cover the inlet of the groove and attenuating the microwave to prevent leakage of the microwave; And And an auxiliary groove formed concave in the inner wall to expand the size of the inner space of the groove adjacent to the inner wall to improve the attenuation characteristics of the microwave. The method of claim 1, The upper end of the inner wall is continuously formed along the longitudinal direction of the auxiliary groove is a heating device using a microwave, characterized in that to cover the upper portion of the auxiliary groove. The method according to claim 1 or 2, The heating device using a microwave, characterized in that the upper end of the inner wall and the protrusion is disposed to face each other. delete A case in which a heating chamber to which microwaves are irradiated is formed; A door for opening and closing the heating chamber; An elongated groove formed along an inner edge of the door and having an inner wall adjacent to the heating chamber when the door is closed; A partition plate extending from a center of the bottom of the groove to define an inner space of the groove; At least one protrusion extending from the door and the partition plate to partially cover the entrance of the groove and attenuating the microwave to prevent leakage of the microwave; And An auxiliary groove formed concave in the inner wall to expand the size of the inner space of the groove adjacent to the inner wall to improve the attenuation characteristics of the microwave; And And a glass attached to the inner surface of the door and including a glass covering the groove.

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