JP7461263B2 - Dielectric Heating Device - Google Patents

Description

The present invention relates to a dielectric heating device.

2. Description of the Related Art A dielectric heating device is known that heats an object placed in a heating chamber by applying a voltage to at least one of two opposing electrodes. In such a dielectric heating device, a technique is known in which a balanced circuit with equal electric field distribution in positive and negative times is used as a load-side circuit including a counter electrode (for example, see Patent Document 1). According to this, by applying voltages with a phase difference of 180° to the two opposing electrodes, it is possible to suppress the difference in electric field strength within the object to be heated and uniformly heat the entire object to be heated.

Patent No. 2884554

In a dielectric heating device in which the positions of two opposing electrodes (e.g., an upper electrode and a lower electrode) are fixed, two objects to be heated may be placed one above the other in the heating chamber in order to reduce heating time and labor. In this case, the distance between the lower object to be heated and the lower electrode is likely to be smaller than the distance between the upper object to be heated and the upper electrode. As a result, even if heating control is performed using the above-mentioned balancing circuit, the electric field strength in the upper object to be heated is likely to be relatively weaker than the electric field strength in the lower object to be heated. When such a difference in electric field strength occurs, even if the lower object to be heated is completely thawed, the upper object to be heated is not completely thawed, which may result in the trouble of reheating only the upper object to be heated.

One aspect of the present disclosure aims to provide a dielectric heating device that can heat multiple objects evenly even when multiple objects are placed in a heating chamber.

A dielectric heating device according to one aspect of the present disclosure includes two heating electrodes facing each other with a gap between them, a high frequency power source that supplies high frequency power to the two heating electrodes, and a plurality of heating electrodes provided between the two heating electrodes. A heating chamber, which is a space in which the objects to be heated can be arranged, and a plurality of objects to be heated are arranged such that the vertical positions of the plurality of objects to be heated are different from each other, and from the center point of a virtual rectangular parallelepiped having the two heating electrodes as both end faces. , a support part that supports at least one of the plurality of heated objects arranged in the heating chamber so that distances to each of the plurality of heated objects are equal.

1 is a diagram showing the overall configuration of a dielectric heating device. FIG. 2 is a diagram illustrating a configuration of a matching circuit. 11 is a graph showing changes in electrode voltages applied to an upper electrode and a lower electrode. 11 is a graph showing a change in an interelectrode voltage generated between an upper electrode and a lower electrode. FIG. 2 is a diagram showing a heating chamber in which an object to be heated is placed in the first embodiment. In the first embodiment, it is a diagram showing a heating chamber in which objects to be heated are placed. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 2nd embodiment. FIG. 11 is a diagram showing a heating chamber in which an object to be heated is placed in a third embodiment. FIG. 11 is a diagram showing a heating chamber in which an object to be heated is placed in a third embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is not arrange|positioned in 4th embodiment. FIG. 13 is a diagram showing a heating chamber in which an object to be heated is placed in a fourth embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 4th embodiment. FIG. 13 is a diagram showing a heating chamber in which an object to be heated is placed in a fifth embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 5th embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 6th embodiment. FIG. 13 is a diagram showing a heating chamber in which an object to be heated is placed in a sixth embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 7th embodiment. It is a figure which shows the heating warehouse in which the to-be-heated object is arrange|positioned in 7th embodiment. FIG. 13 is a diagram showing a configuration of a dielectric heating device according to a modified example. FIG. 13 is a diagram showing the overall configuration of a dielectric heating device according to a modified example. It is a figure showing the composition of the matching circuit concerning a modification. It is a figure showing the whole structure of a dielectric heating device concerning another modification.

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or equivalent elements are denoted by the same reference numerals, and duplicate explanations will be omitted.

First Embodiment
A dielectric heating device 100 according to a first embodiment will be described. Fig. 1 is a diagram showing the overall configuration of the dielectric heating device 100. Fig. 2 is a diagram showing the configuration of matching circuits 104A and 104B. The dielectric heating device 100 applies a high-frequency electric field to an object to be heated, such as food, to perform a heating process, a thawing process, or the like, on the object to be heated.

As shown in FIG. 1, the dielectric heating device 100 includes a heating chamber 101, a drive circuit 102, and a control unit 105. The heating chamber 101 is a metal box-shaped chamber, and has an internal space capable of accommodating an object to be heated. The internal space of the heating chamber 101 is open to the front and can be opened and closed by a door (not shown). FIG. 1 shows the heating chamber 101 as viewed from the front. The upper, lower, left, right, front side, and rear side of FIG. 1 correspond to the upper, lower, left, right, front, and rear sides of the dielectric heating device 100 (i.e., the heating chamber 101), respectively. The metallic heating chamber 101 is grounded by a grounding wire 109 or the like.

The internal space of the heating chamber 101 is provided with two heating electrodes 110, a heating chamber 113, a support portion 114, etc. The two heating electrodes 110 face each other with a gap between them. As an example, the two heating electrodes 110 are an upper electrode 111 and a lower electrode 112 that face each other in the vertical direction. The upper electrode 111 and the lower electrode 112 are rectangular flat plates extending in the front-rear and left-right directions, and are arranged so as to be parallel to each other.

The heating chamber 113 is a space between two heating electrodes 110 (upper electrode 111 and lower electrode 112) in which multiple objects to be heated can be placed. The support portion 114 is a member that supports at least one of the multiple objects to be heated placed in the heating chamber 113, and will be described in detail later.

Drive circuit 102 includes a high frequency power supply 103 and matching circuits 104A and 104B. The high frequency power supply 103 is a power supply circuit that generates high frequency power to be supplied to the two heating electrodes 110. High frequency power supply 103 includes an oscillator 131, a phase shifter 132, variable attenuators 133A, 133B, and amplifiers 134A, 134B. The oscillator 131 is connected to the ground line 109 described above.

Oscillator 131 emits a voltage signal with a frequency band from HF to VHF. The voltage signal emitted by oscillator 131 is input to variable attenuators 133A and 133B, which are connected in parallel to oscillator 131. However, the voltage signal input to variable attenuator 133B has its phase shifted by 180° by phase shifter 132, which is connected between variable attenuator 133B and high frequency power supply 103. Therefore, the phase difference between the voltage signals input to variable attenuators 133A and 133B is 180°.

The voltage signal attenuated to an appropriate level by the variable attenuator 133A is amplified to the desired power by the amplifier 134A and sent to the matching circuit 104A. The voltage signal attenuated to an appropriate level by the variable attenuator 133B is amplified to the desired power by the amplifier 134B and sent to the matching circuit 104B. As a result, the voltage signals sent to the matching circuits 104A and 104B are amplified to the same level of power and have a phase difference of 180°.

As shown in FIG. 2, the matching circuit 104A has an input connected to the amplifier 134A and an output connected to the upper electrode 111. The matching circuit 104A includes a variable coil 201 and variable capacitors 202 and 203. In the matching circuit 104A, the variable coil 201 and the variable capacitor 202 are connected in series to the output of the high frequency power supply 103, and the variable capacitor 203 is connected in parallel to the output of the high frequency power supply 103. The variable capacitor 203 is connected to the ground line 109 described above.

The matching circuit 104A matches the input impedance of the matching circuit 104A and the output impedance of the amplifier 134A by adjusting the values of the variable coil 201 and variable capacitors 202 and 203. Thereby, the impedance on the upper electrode 111 side seen from the high frequency power supply 103 (specifically, the amplifier 134A) can be kept constant, and a voltage signal can be efficiently supplied to the upper electrode 111 side.

The input side of matching circuit 104B is connected to amplifier 134B, and the output side is connected to lower electrode 112. Matching circuit 104B has a configuration similar to that of matching circuit 104A, and matches the input impedance of matching circuit 104B with the output impedance of amplifier 134B. This makes it possible to keep the impedance of the lower electrode 112 side constant as viewed from high frequency power supply 103 (more specifically, amplifier 134B), and efficiently supply a voltage signal to the lower electrode 112 side.

In the drive circuit 102, a voltage whose impedance has been matched by matching circuits 104A and 104B is supplied to a capacitor formed by an upper electrode 111 and a lower electrode 112. As a result, a high frequency electric field is generated between the upper electrode 111 and the lower electrode 112, and the object to be heated disposed between the upper electrode 111 and the lower electrode 112 is dielectrically heated.

FIG. 3A is a graph showing changes in the electrode voltages applied to the upper electrode 111 and the lower electrode 112. In the example of FIG. 3A, the change in the voltage that the high frequency power supply 103 applies to the upper electrode 111 and the lower electrode 112 shows a sine wave whose amplitude varies from "-0.5" to "+0.5" in one cycle. . However, the voltage applied to the upper electrode 111 and the voltage applied to the lower electrode 112 differ in phase shift by 180°.

Figure 3B is a graph showing the change in interelectrode voltage generated between the upper electrode 111 and the lower electrode 112. The interelectrode voltage is the difference between the applied voltage of the upper electrode 111 and the applied voltage of the lower electrode 112. Figure 3B shows the change in the interelectrode voltage of the upper electrode 111 and the lower electrode 112 shown in Figure 3A. This change in interelectrode voltage shows a sine wave whose amplitude varies from "-1.0" to "+1.0" in one cycle, since the amplitude is twice that of the applied voltage of the upper electrode 111 and the lower electrode 112.

In this way, in the dielectric heating device 100, the high frequency power supply 103 applies voltages to the two heating electrodes 110 so that the phase difference between the voltages applied to the two heating electrodes 110 is 180°. With this type of heating control using a balanced circuit method, it is possible to generate a larger interelectrode voltage while suppressing the maximum voltage applied to one heating electrode 110, compared to heating control using an unbalanced circuit method in which a voltage is applied to one of the two heating electrodes 110.

The details of the support part 114 according to the first embodiment will be explained. As shown in FIG. 1, the support section 114 includes a tray 141 and a shelf support 142. The tray 141 is an insulating plate-like member on which at least one of a plurality of objects to be heated is placed. The shelf support 142 receives the tray 141 placed in the heating chamber 113 and positions the tray 141 in the vertical direction.

For example, the shelf support 142 is provided on a side wall that covers the side of the heating chamber 113. Specifically, the shelf receiver 142 has a plurality of receivers provided on the right and left walls of the heating chamber 101 that cover both left and right sides of the heating chamber 113. Each of the plurality of receiving parts is a component, a protrusion, etc., which are provided in a pair on the left and right sides and can support both ends of the tray 141 from below. The plurality of receiving parts are arranged in line in the vertical direction at equal intervals, and can support the tray 141 at mutually different vertical positions.

In the shelf support 142, the vertical position of the tray 141 changes depending on which of the multiple receiving parts the tray 141 is placed on. In other words, the shelf support 142 can change the vertical position of the tray 141 (i.e., the vertical position of the heated object on the tray 141) in stages using the multiple receiving parts. The shelf support 142 may be configured to have one receiving part that supports the tray 141, and to allow a human to manually change the vertical position of this receiving part.

In the first embodiment, assuming that the object to be heated is placed only on the tray 141, the shelf support 142 is provided only below the horizontal plane V1 passing through the center point O of the rectangular parallelepiped R. Therefore, the tray 141 supported by the shelf support 142 is disposed below the horizontal plane V1, regardless of which of the plurality of support parts it is supported by.

The support portion 114 extends from the center point O of a virtual rectangular parallelepiped R having two heating electrodes 110 as both end faces to each of the plurality of heated objects so that the vertical positions of the plurality of heated objects are different from each other. At least one of the plurality of objects to be heated arranged in the heating chamber 113 is supported so that the distances between the two objects are equal. This will be explained in detail below.

Figures 4A and 4B are diagrams showing the heating chamber 101 in which objects to be heated are placed in the first embodiment. For example, when two objects to be heated T1 and T2 are to be heated simultaneously using the dielectric heating device 100, the user places the objects to be heated T1 and T2 one above the other in the heating chamber 113. As an example, the objects to be heated T1 and T2 are assumed to be substantially the same in size, shape, material, contents, etc.

In the example shown in FIG. 4A, the objects to be heated T1 and T2 are stacked and arranged on the lower electrode 112 without using a tray 141. However, in this example, the distances from the center point O to the objects to be heated T1 and T2 are different. In detail, as viewed from the center point O, the upper object to be heated T1 is closer than the lower object to be heated T2. The distance L1 between the upper electrode 111 and the upper object to be heated T1 is greater than the distance L2 between the lower electrode 112 and the lower object to be heated T2.

In the dielectric heating device 100, the closer the object to be heated is to the center point O, the smaller the electric field strength acting on the object to be heated tends to be. In other words, the farther the object to be heated is from the heating electrode 110, the smaller the electric field strength acting on the object is likely to become. Therefore, when heating control is executed in the example shown in FIG. 4A, the electric field intensity acting on the object to be heated T1 becomes smaller than the electric field intensity acting on the object to be heated T2, and the objects to be heated T1 and T2 are equally heated. There is a possibility that it cannot be done.

In the example shown in FIG. 4B, objects to be heated T1 and T2 are arranged overlapping on a tray 141 supported by a shelf support 142. Of the multiple support parts of the shelf support 142, the upper end support part supports the tray 141 at a relatively high position, and supports the tray 141. The boundary between the objects to be heated T1 and T2 that overlap on the tray 141 is arranged above the center point O.

In this example, too, the distances from the center point O to the objects to be heated T1 and T2 are different. In detail, as viewed from the center point O, the upper object to be heated T1 is farther away than the lower object to be heated T2. Distance L1 is smaller than distance L2. Therefore, when heating control is executed, the electric field strength acting on the object to be heated T1 becomes greater than the electric field strength acting on the object to be heated T2, and there is a risk that the objects to be heated T1 and T2 cannot be heated evenly.

In the example shown in FIG. 1, objects to be heated T1 and T2 are stacked on a tray 141 supported by a shelf support 142. Of the multiple support parts of the shelf support 142, the tray 141 is supported by a middle support part that supports the tray 141 at a standard height. The center point O is near the boundary between the objects to be heated T1 and T2 that overlap on the tray 141. In this example, the objects to be heated T1 and T2 are located at different vertical positions, and the distances from the center point O to the objects to be heated T1 and T2 are equal. That is, the distance L1 and the distance L2 are equal. Therefore, when heating control is executed, the electric field strength acting on the object to be heated T1 becomes equal to the electric field strength acting on the object to be heated T2, and the objects to be heated T1 and T2 can be heated evenly.

According to the first embodiment, for example, by switching the support part of the shelf support 142 that supports the tray 141 according to the thickness of the objects to be heated T1, T2, the vertical positions of the objects to be heated T1, T2 on the tray 141 can be adjusted so that the center point O is positioned midway between the objects to be heated T1, T2. This allows the objects to be heated T1, T2 placed in the heating chamber 113 to be heated evenly.

Second Embodiment
A dielectric heating device 100 according to a second embodiment will be described. In the following embodiments, components having substantially the same functions as those in the first embodiment will be referred to by the same reference numerals, and descriptions will be omitted. Only the differences from the first embodiment will be described. Fig. 5 is a diagram showing a heating chamber 101 in which an object to be heated is placed in the second embodiment.

The support portion 114 according to the second embodiment has the same structure as that of the first embodiment, but differs in the following respects. As shown in FIG. 5, in the second embodiment, it is assumed that multiple objects to be heated are distributed and placed on the tray 141 and the lower electrode 112, and the shelf support 142 is provided only above the horizontal plane V1 passing through the center point O of the rectangular parallelepiped R. Therefore, the tray 141 supported by the shelf support 142 is positioned above the horizontal plane V1 regardless of which of the multiple supports it is supported by.

In the example shown in FIG. 5, the upper heated object T1 is placed on the tray 141, and the lower heated object T2 is placed on the lower electrode 112. The tray 141 is supported by the middle receiving part that supports the tray 141 at a standard height among the plurality of receiving parts that the shelf support 142 has. The center point O is located near the intermediate position between the object to be heated T1 and the object to be heated T2. In this example, the vertical positions of the objects to be heated T1 and T2 are different from each other, and the distances from the center point O to each of the objects to be heated T1 and T2 are equal, so the distance L1 and the distance L2 are equal. When the heating control is executed, the objects to be heated T1 and T2 can be heated equally, as in the first embodiment.

According to the second embodiment, for example, by switching the support part of the shelf support 142 that supports the tray 141 depending on the thickness of the objects to be heated T1 and T2, the vertical position of the upper object to be heated T1 on the tray 141 can be adjusted so that the center point O is positioned midway between the objects to be heated T1 and T2. This allows the objects to be heated T1 and T2 placed in the heating chamber 113 to be heated evenly.

Third Embodiment
A dielectric heating device 100 according to a third embodiment will be described. Figures 6A and 6B are diagrams showing a heating chamber 101 in which an object to be heated is placed in the third embodiment. As shown in Figures 6A and 6B, the dielectric heating device 100 according to the third embodiment has a similar structure to the first embodiment, but differs in that it includes a first index 600. The first index 600 visually indicates the center position between the two heating electrodes 110 in the vertical direction.

As mentioned above, in order to uniformly heat the objects T1 and T2, the vertical position of the tray 141 must be adjusted so that the center point O is located near the boundary between the objects T1 and T2. is preferred. However, since the center point O is a virtual point, humans cannot visually recognize it. The first indicator 600 allows the tray 141 to be placed in the optimal position without the user being aware of the center point O.

For example, the first indicator 600 is provided on the rear wall of the wall inside the heating chamber 101 on the opposite side to the front opening. The first indicator 600 is a marker that extends in the left-right direction at the same vertical position as the center point O at the rear of the heating chamber 113. The first indicator 600 may be printed or welded to the inner wall of the heating chamber 101, or may be a structure that protrudes forward from the inner wall.

When the user views the inside of the heating chamber 101 from the front side, the first indicator 600 appears at a position overlapping the center point O. As shown in FIGS. 6A and 6B, the tray 141 is supported by the shelf support 142 in the vertical direction so that the first indicator 600 is placed near the boundary between the heated objects T1 and T2 on the tray 141 when viewed from the front. The position may be adjusted.

In the example of FIG. 6B, since the objects to be heated T1 and T2 are thicker than the example of FIG. 6A, the shelf support 142 supports the tray 141 at a lower position. However, in both FIGS. 6A and 6B, since the first indicator 600 is arranged near the boundary between the objects to be heated T1 and T2, the objects to be heated T1 and T2 can be heated evenly. As described above, by adjusting the vertical position of the tray 141 with reference to the first indicator 600, the user can easily and accurately place the objects to be heated T1 and T2 at positions where they can be heated evenly.

<Fourth embodiment>
A dielectric heating device 100 according to a fourth embodiment will be described. FIG. 7A is a diagram showing the heating chamber 101 in which the object to be heated is not placed in the heating chamber 113 in the fourth embodiment. FIGS. 7B and 7C are diagrams showing a heating chamber 101 in which objects to be heated are placed in the fourth embodiment. As shown in FIG. 7A, a dielectric heating device 100 according to the fourth embodiment has the same structure as the second embodiment, but differs in that it includes a second indicator 700. The second indicator 700 visually indicates a combination of positions that are equidistant from each of the two heating electrodes 110.

As mentioned above, in order to uniformly heat the objects T1 and T2, it is preferable to adjust the vertical position of the tray 141 so that the distance L1 and the distance L2 are equal. However, humans cannot visually recognize the distances L1 and L2. The second indicator 700 allows the tray 141 to be placed at the optimal position even if the user does not recognize the distances L1 and L2.

For example, the second indicator 700, like the first indicator 600, is provided on the rear wall inside the heating chamber 101. The second indicators 700 are a plurality of sets of markers that indicate the vertical positions of the objects to be heated T1 and T2 where the distances L1 and L2 are equal to each other. The plurality of sets of markers correspond to objects to be heated T1 and T2 having different thicknesses, respectively.

In the second indicator 700, each of the multiple sets of markers (i.e., one set of markers) consists of an upper marker indicating the bottom end position of the upper heated object T1, and a lower marker indicating the top end position of the lower heated object T2. The markers of a set (upper marker and lower marker) are displayed in the same display manner (thickness, length, etc.) so that it is easy to visually recognize that they form the same set. The multiple sets of markers are displayed in different display manners (thickness, length, etc.) so that they can be visually distinguished from each other as different sets.

In the example shown in FIG. 7B, when the user places the object to be heated T2 on the lower electrode 112, the upper end of the object to be heated T2 is located near the second lower marker from the bottom among the second indicators 700 when viewed from the front. The user identifies an upper marker that has the same display mode as this lower marker (i.e., the second upper marker from the top), and adjusts the vertical position of the tray 141 supported by the shelf bracket 142 so that the lower end of the object to be heated T1 is located near this upper marker.

In the example shown in FIG. 7C, the objects to be heated T1 and T2 are thicker than those in FIG. 7B. The upper end of the object to be heated T2 placed on the lower electrode 112 is located near the third lower marker from the bottom when viewed from the front. The user adjusts the vertical position of the tray 141 supported by the shelf bracket 142 so that the lower end of the object to be heated T1 is located near the upper marker that has the same display mode as this lower marker (i.e., the third upper marker from the top).

In both FIGS. 7B and 7C, since the distance L1 and the distance L2 are equal, the objects to be heated T1 and T2 can be heated equally. As described above, by adjusting the vertical position of the tray 141 with reference to the second indicator 700, the user can easily and accurately arrange the objects to be heated T1 and T2 at positions where they can be heated evenly.

Fifth Embodiment
A dielectric heating device 100 according to a fifth embodiment will be described. Figures 8A and 8B are diagrams showing a heating chamber 101 in which an object to be heated is placed in the fifth embodiment. As shown in Figure 8A, the dielectric heating device 100 according to the fifth embodiment differs from the first embodiment in that the support part 114 is movable.

As shown in FIG. 8A, the support section 114 according to the fifth embodiment includes an insulating tray 141 and a lifting mechanism 143. The lifting mechanism 143 raises and lowers the tray 141 arranged in the heating chamber 113 to position the tray 141 in the up-down direction. For example, the lifting mechanism 143 is a pair of left and right movable legs extending upward from the bottom wall inside the heating chamber 101, and supports the tray 141 installed at the upper ends thereof.

The elevating mechanism 143 is capable of elevating and lowering the tray 141 by receiving driving force from a motor (not shown). By operating the up/down button provided on the dielectric heating device 100, the user can drive the motor and raise/lower the lifting mechanism 143 to an arbitrary height. In this embodiment, the lifting mechanism 143 lifts and lowers the tray 141 only below the horizontal plane V1 passing through the center point O of the virtual rectangular parallelepiped R.

The user places the objects to be heated T1, T2 on the tray 141, one above the other, and operates the lifting button to drive the lifting mechanism 143. At this time, the user positions the tray 141 in the vertical direction so that the center point O is located near the boundary between the objects to be heated T1, T2. This allows the objects to be heated T1, T2 placed in the heating chamber 113 to be heated evenly. In this embodiment, the first indicator 600 described above may be provided. In this case, as in the third embodiment, the tray 141 that is raised and lowered can be easily and accurately positioned so that the objects to be heated T1, T2 are located in a position where they can be heated evenly.

As shown in FIG. 8B, when one object to be heated T is heated in the heating chamber 113, the lifting mechanism 143 may move the tray 141 to the lower end of its movable range (e.g., the upper surface of the lower electrode 112). This allows the object to be placed in the heating chamber 113 and heated without interfering with the tray 141, even if the object to be heated T is thick, for example. In this embodiment, the lifting mechanism 143 may also move the tray 141 above the horizontal plane V1, for example, in response to a user instruction.

Sixth Embodiment
A dielectric heating device 100 according to a sixth embodiment will be described. Figures 9A and 9B are diagrams showing a heating chamber 101 in which an object to be heated is placed in the sixth embodiment. As shown in Figure 9A, the dielectric heating device 100 according to the sixth embodiment differs from the second embodiment in that the support part 114 is movable.

As shown in FIG. 9A, the support unit 114 according to the sixth embodiment includes a tray 141 and a lifting mechanism 143, similar to the fifth embodiment. For example, the lifting mechanism 143 is a pair of left and right movable arms extending downward from the top wall inside the heating chamber 101, and supports the tray 141 installed at the lower end thereof. In this embodiment, the lifting mechanism 143 raises and lowers the tray 141 only above a horizontal plane V1 passing through the center point O of the imaginary rectangular parallelepiped R.

The user places the object to be heated T1 on the tray 141, places the object to be heated T1 on the lower electrode 112, and operates the lifting button to drive the lifting mechanism 143. At this time, the user positions the tray 141 in the vertical direction so that the distance L1 and the distance L2 are equal. This allows the objects to be heated T1 and T2 placed in the heating chamber 113 to be heated evenly. In this embodiment, the second indicator 700 described above may be provided. In this case, as in the fourth embodiment, the tray 141 that is raised and lowered can be easily and accurately positioned so that the objects to be heated T1 and T2 are placed in a position where they can be heated evenly.

As shown in FIG. 9B, when one object to be heated T is heated in the heating chamber 113, the lifting mechanism 143 may move the tray 141 to the upper end of its movable range (e.g., the lower surface of the upper electrode 111). This allows the object to be placed in the heating chamber 113 and heated without interfering with the tray 141, even if the object to be heated T is thick, for example. In this embodiment, the lifting mechanism 143 may also move the tray 141 below the horizontal plane V1, for example, in response to a user instruction.

Seventh Embodiment
A dielectric heating device 100 according to the seventh embodiment will be described. Figures 10A and 10B are diagrams showing a heating chamber 101 in which an object to be heated is placed in the seventh embodiment. As shown in Figures 10A and 10B, the dielectric heating device 100 according to the seventh embodiment differs from the first to sixth embodiments in that the two heating electrodes 110 are a left electrode 1011 and a right electrode 1012 that face each other in the left-right direction.

In this embodiment, the heating chamber 101 is provided with an inner wall 1000 surrounding a heating chamber 113 provided therein. Inner wall 1000 is made of a non-insulating resin material. Since the inner wall 1000 does not cover the front of the heating chamber 113, the heating chamber 113 is open to the front. The left electrode 1011 is placed on the left side of the heating chamber 113 with the inner wall 1000 interposed therebetween. The right electrode 1012 is placed on the right side of the heating chamber 113 with the inner wall 1000 interposed therebetween. The left electrode 1011 and the right electrode 1012 have a rectangular flat plate shape extending in the front-rear, up-down direction, and are arranged parallel to each other.

In the example shown in FIG. 10A, the support portion 114 is similar to the first embodiment, but the shelf support 142 is provided on the inner wall 1000. The shelf support 142 is provided only below the horizontal plane V1, and supports the tray 141 on which the objects to be heated T1 and T2 are placed. Similar to the first embodiment, the vertical position of the tray 141 can be adjusted so that the center point O is located between the objects to be heated T1 and T2.

In the example shown in FIG. 10B, the support portion 114 is similar to the second embodiment, but the shelf support 142 is provided on the inner wall 1000. The shelf support 142 is provided only above the horizontal plane V1, and supports the tray 141 on which the upper heated object T1 is placed. The lower heated object T1 is arranged on the bottom surface of the heating chamber 113. Similar to the second embodiment, the vertical position of the tray 141 can be adjusted so that the center point O is located between the objects to be heated T1 and T2.

In the example shown in Figures 10A and 10B, the objects to be heated T1 and T2 are located at different vertical positions, and the distances from the center point O to the objects to be heated T1 and T2 are equal, so the distances L1 and L2 are equal. As a result, when heating control is performed, the objects to be heated T1 and T2 can be heated evenly.

The present disclosure is not limited to the above-described embodiments, and may be replaced with a configuration that is substantially the same as the configuration shown in the above-described embodiments, a configuration that provides the same action and effect, or a configuration that can achieve the same purpose.

(1) In the above embodiment, the support part 114 supports a plurality of heated objects T1 and T2 such that the vertical positions of the heated objects T1 and T2 are different from each other and the distances from the center point O to each of the plurality of heated objects are equal. The case where at least one of the objects to be heated is supported is illustrated. Furthermore, the support part 114 supports a plurality of objects arranged in the heating chamber 113 such that the distances from a straight line (or plane) passing through the center point O of the virtual rectangular parallelepiped R to each of the plurality of objects to be heated are equal. At least one of the heating objects may be supported.

The first to seventh embodiments disclose that the support portion 114 can support at least one of a plurality of objects to be heated so as to satisfy the above conditions. In the example shown in FIG. 1, the support part 114 supports both the objects to be heated T1 and T2 so that the distances from the horizontal line passing through the center point O (and the horizontal plane V1) to each of the objects to be heated T1 and T2 are equal. are doing. In the example shown in FIG. 5, the support part 114 supports the upper heated object T1 so that the distances from the horizontal line passing through the center point O (and the horizontal plane V1) to each of the heated objects T1 and T2 are equal. There is.

The straight line passing through the center point O of the virtual rectangular solid R is not limited to a horizontal line, but may be a straight line that is inclined so as to intersect with the horizontal line. The plane passing through the center point O of the virtual rectangular solid R is not limited to the horizontal plane V1, but may be a plane that is inclined so as to intersect with the horizontal plane V1.

(2) As described in the above embodiment, the optimal vertical position of the tray 141 varies depending on the thickness of the objects to be heated T1, T2. Therefore, the dielectric heating device 100 may inform the user of the optimal position of the tray 141, as exemplified below.

Figure 11 is a diagram showing the device configuration of a dielectric heating device 100 according to a modified example. As shown in Figure 11, the dielectric heating device 100 according to the modified example has a display 1101 and a barcode reader 1102. The object to be heated T is provided with a barcode 1103 showing information about the object to be heated T.

For example, if the barcode 1103 indicates identification information of the object to be heated T, the control unit 105 of the dielectric heating device 100 identifies the optimal position of the tray 141 based on the identification information read from the barcode 1103 by the barcode reader 1102. As an example, the control unit of the dielectric heating device 100 may inquire of a server (not shown) to identify the optimal position of the tray 141 that corresponds to the read identification information.

When the barcode 1103 indicates thickness information of the object to be heated T, the control unit 105 of the dielectric heating device 100 identifies the optimal position of the tray 141 based on the thickness information read from the barcode 1103 by the barcode reader 1102. do. As an example, the control unit of the dielectric heating device 100 may specify the optimal position of the tray 141 corresponding to the read thickness information by referring to a table stored in the dielectric heating device 100 in advance.

The control unit 105 displays the identified optimal position for the tray 141 on the display 1101. The dielectric heating device 100 of this modified example has the same configuration as the first or second embodiment. In the example shown in FIG. 11, the "middle level," one of the three receiving sections (lower level, middle level, upper level) of the shelf support 142, is displayed on the display 1101 as the optimal position for the tray 141. The user can refer to the display 1101 and place the tray 141 on the middle level of the shelf support 142, thereby placing the two objects to be heated T in a position where they can be heated evenly.

When the dielectric heating device 100 has a configuration similar to that of the third or fourth embodiment, a numerical value indicating the optimal position of the tray 141 may be displayed on the display 1101. The user operates the lift button to drive the lift mechanism 143, and raises or lowers the tray 141 to a position corresponding to the numerical value displayed on the display 1101. In this case, too, the two objects to be heated T can be positioned so that they can be heated evenly.

The control unit 105 may display the optimal position of the tray 141 when the barcode 1103 is read, regardless of the number of objects T to be heated. Alternatively, the control unit 105 may display the optimal position of the tray 141 only when two objects T to be heated are heated simultaneously.

For example, when the user instructs simultaneous heating of two objects T, the optimal position of the tray 141 may be displayed. Alternatively, if the control unit 105 prestores the matching state of the matching circuits 104A, 104B when one object T is heated and the matching state of the matching circuits 104A, 104B when two objects T are heated simultaneously, the control unit 105 can identify the number of objects T based on the matching state during heating control. When the control unit 105 determines that two objects T are being heated simultaneously, the control unit 105 may display the optimal position of the tray 141.

(3) In the above embodiment, the user manually adjusts the position at which the shelf support 142 supports the tray 141, but the dielectric heating device 100 may adjust the vertical position of the tray 141. For example, in the dielectric heating device 100 of the third or fourth embodiment, when the user specifies the vertical position of the tray 141, the control unit 105 drives the lifting mechanism 143 to raise or lower the tray 141 to the specified position.

As described above, the control unit 105 can specify the optimal position of the tray 141 based on the information read from the barcode 1103 by the barcode reader 1102. In this case, the control unit 105 may drive the lifting mechanism 143 to move the tray 141 up and down to the specified position.

(4) The configuration of the drive circuit 102 is not limited to the above embodiment, and various configurations can be applied. Fig. 12A is a diagram showing the overall configuration of a dielectric heating device 100 according to a modified example. Fig. 12B is a diagram showing the configuration of a matching circuit 104 according to a modified example. Fig. 13 is a diagram showing the overall configuration of a dielectric heating device 100 according to another modified example.

In the drive circuit 102 of the above embodiment (see FIG. 1), if the characteristics of the two heating electrodes 110 match, no current flows through the ground wire 109 during heating control. In this case, the drive circuit 102 shown in FIG. 1 becomes equivalent to the drive circuit 102 shown in FIG. 12A by omitting the ground wire 109 and integrating the matching circuits 104A and 104B into one. Therefore, if the characteristics of the two heating electrodes 110 match, the drive circuit 102 may be configured as shown in FIG. 12A.

In this case, the high frequency power supply 103 is connected to one matching circuit 104. As shown in FIG. 12B, the matching circuit 104 includes variable coils 201A and 201B, variable capacitors 202A and 202B, and a variable capacitor 203. The variable coil 201A and the variable capacitor 202A are connected in series to the amplifier 134A. The variable coil 201B and the variable capacitor 202B are connected in series to the amplifier 134B. The variable capacitor 203 is connected in parallel to the output of the high frequency power supply 103.

In another modification of the drive circuit 102 shown in FIG. 13, a high frequency power source 103 and a matching circuit 104 are connected via an unbalanced-balanced circuit 1300. In the high frequency power supply 103, an oscillator 131, a variable attenuator 133, and an amplifier 134 are directly connected. Matching circuit 104 has the same configuration as in FIG. 12B. The unbalanced-balanced circuit (balun) 1300 converts the voltage signal input from the high frequency power supply 103 into a balanced voltage and inputs it to the matching circuit 104. Thereby, the drive circuit 102 can perform balanced circuit type heating control similarly to the above embodiment.

100 Dielectric heating device, 103 High frequency power source, 110 Heating electrode, 113 Heating chamber, 114 Support, 141 Tray, 142 Shelf support, 143 Lifting mechanism

Claims (8)

Two heating electrodes facing each other in a vertical direction with a gap therebetween;
A high frequency power source for supplying high frequency power to the two heating electrodes;
A heating chamber is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
A support section that supports at least one of the two objects to be heated, which are arranged in the heating chamber, such that the two objects to be heated are located at different vertical positions from each other, and such that a distance between the upper heating electrode and a lower surface of the object to be heated on the upper side is equal to a distance between the lower heating electrode and a top surface of the object to be heated on the lower side;
Equipped with
The support portion is
An insulating tray on which at least one of the two objects to be heated is placed;
a shelf support that receives the tray placed in the heating chamber and positions the tray in the up-down direction,
The shelf support is provided only below a horizontal plane passing through the middle of the two heating electrodes.
Dielectric heating device. Two heating electrodes facing each other in a vertical direction with a gap therebetween;
a high frequency power source that supplies high frequency power to the two heating electrodes;
A heating chamber is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
The vertical positions of the two heated objects are different from each other, and the distance between the upper heating electrode and the lower surface of the upper heated object is such that the distance between the lower heating electrode and the lower heated object is a support part that supports at least one of the two objects to be heated arranged in the heating chamber so that the distance from the top surface is equal to the distance from the top surface;
Equipped with
The support portion is
an insulating tray on which at least one of the two objects to be heated is placed;
a shelf support that receives the tray disposed in the heating chamber and positions the tray in the vertical direction;
The shelf support is provided only above a horizontal plane passing between the two heating electrodes,
Dielectric heating device. The high frequency power supply applies voltages to the two heating electrodes such that the phase difference between the voltages applied to the two heating electrodes is 180°.
3. The dielectric heating device according to claim 1 or 2 . The shelf support is provided on a side wall covering a side of the heating chamber,
A dielectric heating device according to any one of claims 1 to 3 . two heating electrodes facing each other in the vertical direction with a space between them;
a high frequency power source that supplies high frequency power to the two heating electrodes;
a heating chamber that is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
The vertical positions of the two heated objects are different from each other, and the distance between the upper heating electrode and the lower surface of the upper heated object is such that the distance between the lower heating electrode and the lower heated object is a support part that supports at least one of the two objects to be heated arranged in the heating chamber so that the distance from the top surface is equal to the distance from the top surface;
Equipped with
The support part is
an insulating tray on which at least one of the two objects to be heated is placed;
an elevating mechanism for elevating and lowering the tray disposed in the heating chamber to position the tray in the vertical direction;
The lifting mechanism raises and lowers the tray only below a horizontal plane passing between the two heating electrodes .
Dielectric heating device. Two heating electrodes facing each other in a vertical direction with a gap therebetween;
a high frequency power source for supplying high frequency power to the two heating electrodes;
A heating chamber is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
A support section that supports at least one of the two objects to be heated, which are arranged in the heating chamber, such that the two objects to be heated are located at different vertical positions from each other, and such that a distance between the upper heating electrode and a lower surface of the object to be heated on the upper side is equal to a distance between the lower heating electrode and a top surface of the object to be heated on the lower side;
Equipped with
The support portion is
An insulating tray on which at least one of the two objects to be heated is placed;
a lifting mechanism that lifts and lowers the tray disposed in the heating chamber to position the tray in the up-down direction,
The lifting mechanism lifts and lowers the tray only above a horizontal plane passing between the two heating electrodes .
Dielectric heating device. Two heating electrodes facing each other in a vertical direction with a gap therebetween;
a high frequency power source for supplying high frequency power to the two heating electrodes;
A heating chamber is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
A support part that supports at least one of the two objects to be heated, which are arranged in the heating chamber, so that the vertical positions of the two objects to be heated are different from each other;
Equipped with
The support portion is
An insulating tray on which at least one of the two objects to be heated is placed;
a shelf support that receives the tray placed in the heating chamber and positions the tray in the up-down direction,
A first indicator visually indicates a center position between the two heating electrodes in the vertical direction .
Dielectric heating device. two heating electrodes facing each other in the vertical direction with a space between them;
a high frequency power source that supplies high frequency power to the two heating electrodes;
a heating chamber that is provided between the two heating electrodes and is a space in which at least two objects to be heated can be placed;
a support portion that supports at least one of the two heated objects arranged in the heating chamber so that the vertical positions of the two heated objects are different from each other;
Equipped with
The support part is
an insulating tray on which at least one of the two objects to be heated is placed;
a shelf support that receives the tray disposed in the heating chamber and positions the tray in the vertical direction;
a second indicator visually indicating a combination of positions equidistant from each of the two heating electrodes ;
Dielectric heating device.

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