JP5217881B2 - Microwave processing equipment - Google Patents

Description

  The present invention relates to a microwave processing apparatus including a microwave generation unit configured using a semiconductor element.

  A conventional microwave processing apparatus of this type is generally composed of a rectangular parallelepiped heating chamber and includes one or a plurality of power feeding units. As a structure of a some electric power feeding part, there exists a thing which provided the electric power feeding part in the upper wall surface and bottom wall surface of a heating chamber, and supplied the microwave to each electric power feeding part from the microwave generation part for exclusive use.

  In addition, with the aim of promoting uniform heating of the object to be heated, the heating chamber is formed in a polyhedron having six or more faces, and a radiation antenna as a power feeding portion protrudes from a part or all of each wall surface into the heating chamber. (See, for example, Patent Document 1). And, it is said that mutual interference can be prevented by arranging the radiation antennas on different surfaces. Furthermore, since the radiating antennas are directed in different directions, the radiated radio waves propagate in all directions in the heating chamber and are reflected and scattered by the wall surface, so that the radio waves are uniformly distributed in the heating chamber. .

  Further, among each antenna connected to a solid-state oscillator, there is an antenna in which at least two antennas are arranged on the same wall surface of a heating chamber (see, for example, Patent Document 2). Further, it is described that heating unevenness is reduced by increasing the number of installed antennas, uniform heating can be performed, and the influence of reflected waves is eliminated due to the orientation relationship between the antennas.

Also, with a phase shifter, a semiconductor oscillating unit, a distributing unit that divides the output of the oscillating unit into a plurality of components, a plurality of amplifying units that respectively amplify the distributed outputs, and a synthesis that combines the outputs of the amplifying units And a phase shifter is provided between the distribution unit and the amplification unit (see, for example, Patent Document 3). The phase shifter is configured to switch the microwave pass line length according to the on / off characteristics of the diode. Further, the combining unit can use two 90-degree and 180-degree hybrids, so that the output power of the combining unit can be made two. By controlling the phase shifter, the power ratio of two outputs can be changed, or two outputs The phase between them can be in phase or out of phase.

In addition, this type of microwave processing apparatus generally uses a vacuum tube called a magnetron in a microwave generation section as represented by a microwave oven.
JP-A-52-19342 Japanese Utility Model Publication No. 52-16654 JP 56-132793 A

  However, the conventional multiple power feeding units are arranged so as to avoid interference between the power feeding units, and the microwaves radiated from the respective power feeding units have different radiation directions but are heated. Scattering due to reflection on the wall surface of the room and the scattered microwaves are scattered over a wide range by repeated scattering and colliding with the wall surface, preventing interference from microwaves radiated from other radiation antennas Impossible.

  In addition, in the case where a plurality of antennas are arranged on the same wall surface of the heating chamber, the difference from simply providing a plurality of antennas is not clear, and there is no disclosure of the contents of the effect of providing the same wall surface. Only the possibility of realization is described.

  In addition, in the case of a device equipped with a phase shifter, the microwaves radiated from the two outputs of the combining unit can change the radiated power ratio and phase difference from the two radiating antennas by changing the phase by the phase shifter. Although it is possible to change it instantaneously, it is difficult to heat the objects to be heated in various shapes, types and quantities stored in the heating chamber to which microwaves are supplied by the radiation to the desired state. Had.

  The present invention solves the above-described conventional problems, and optimally interfers microwaves radiated from each of a plurality of power supply units, thereby allowing various shapes, types, and amounts of objects to be heated to be in a desired state. An object of the present invention is to provide a microwave processing apparatus that heats the heat.

In order to solve the above-described conventional problems, a microwave processing apparatus of the present invention includes a heating chamber that accommodates an object to be heated , an oscillation unit, and a power distribution unit that distributes and outputs the output of the oscillation unit to a plurality of units. A phase variable unit that varies at least one output phase of the power distribution unit, an amplification unit that amplifies the power of the output of the power distribution unit and / or the phase variable unit, and an output of the amplification unit as the heating chamber A power supply unit that supplies power to the power supply unit, a power detection unit that detects microwave power reflected from each of the power supply units in the direction of the amplification unit, and a control unit that controls the oscillation frequency of the oscillation unit and the phase amount of the phase variable unit The power feeding section is arranged at an even number of four or more places on the bottom wall surface of the heating chamber, and a plurality of combinations of the two power feeding sections are provided approximately symmetrically with respect to a point on one axis, 2 constituting a combination of parts The lines connecting the two power feeding sections are arranged so as to intersect each other in the combination of the plurality of power feeding sections, and the combination of the power feeding sections is arranged so that the excitation directions of the microwave electric field radiated to the heating chamber match. The control unit is configured to relatively control the phase of the microwave supplied from the power feeding unit between the combinations of the plurality of power feeding units, and a combination of a plurality of power feeding units arranged substantially symmetrically. radiation was low power microwaves strongly interference from further distribution of microwave power high directivity high power is generated in the heating chamber, the object to be heated is efficiently heated to be stored in the heating chamber, the relative The distribution of microwave power with strong directivity generated by mutual interference between microwaves whose phases are controlled in phase can be moved by the phase difference, so it is best to use heated objects of various shapes, types, and quantities. Possible to provide a device for heating.

  The microwave processing apparatus of the present invention radiates microwaves from a plurality of power feeding sections with substantially symmetrical radiation characteristics into a heating chamber and optimally interferes with each other, thereby allowing various shapes, types, and amounts of heated objects to be heated. A microwave processing apparatus for heating an object to a desired state can be provided.

A first aspect of the invention is a heating chamber that accommodates an object to be heated, an oscillation unit, a power distribution unit that distributes and outputs the output of the oscillation unit, and at least one output phase of the power distribution unit is variable. A phase variable unit that performs power amplification of the output of the power distribution unit and / or the phase variable unit, a power supply unit that supplies the output of the amplification unit to the heating chamber, and a power supply unit A power detection unit that detects microwave power reflected in the direction of the amplification unit; and a control unit that controls an oscillation frequency of the oscillation unit and a phase amount of the phase variable unit . A plurality of combinations of the two power feeding portions are arranged in an even number of four or more places on the bottom wall surface, and are approximately symmetrical with respect to a point on one axis, and between the two power feeding portions constituting the combination of the power feeding portions. A connecting line is a combination of the plurality of power feeding sections. The combination of the power feeding units is arranged so that the excitation directions of the microwave electric fields radiated to the heating chamber coincide with each other, and the control unit is configured to control the phase of the microwaves supplied from the power feeding unit. Is configured to relatively control between the combination of the plurality of power supply units , the low-power microwaves radiated from the combination of the plurality of power supply units arranged substantially symmetrically strongly interfere with each other, In addition , a highly directional microwave power distribution with high directivity is generated in the heating chamber, the object to be heated stored in the heating chamber is efficiently heated, and is generated by mutual interference between microwaves whose phases are controlled relatively. distribution of strong directivity of the microwave power, as it can move the distribution position by the phase difference, it is possible to heat various shapes, types and quantity of different object to be heated optimally.

  The second aspect of the invention is particularly configured such that the symmetrical center point of the substantially symmetrically arranged feeding unit combination of the first aspect is provided on a vertical axis passing through the substantial center of the heated object installation horizontal plane of the heating chamber. By making the power supply unit arrangement center and the heated object installation surface center coincide, a strong directional microwave power distribution is generated at the heated object installation surface center due to the mutual interference of the emitted microwaves. It is possible to efficiently heat the object to be heated of various shapes, types, and amounts by efficiently absorbing the object to be heated installed in the center of the object to be heated installation surface.

  In particular, the third invention feeds power to all vertex positions of one regular polygon centered on one axis where the symmetrical center point of the substantially symmetrically arranged feeding portion combination of the first or second invention exists. The distance from the central point of the substantially symmetrical arrangement to each power supply unit is equal, the power supply unit is arranged in an equal direction with respect to the center point, and the influence of the position of the power supply unit with respect to the center point The mutual interference of the radiated microwaves can generate a stronger directional microwave power distribution, and the microwaves radiated into the heating chamber can be efficiently absorbed by the object to be heated. It is possible to efficiently heat objects to be heated having different shapes, types and amounts.

  In the fourth invention, in particular, the plurality of power feeding units according to the first invention are arranged at a position of a half wavelength or less from the center point of the substantially symmetrical arrangement, and radiation from the plurality of power feeding units. Intense mutual interference between the generated microwaves, generate a more directional microwave power distribution, and efficiently absorb the microwaves radiated into the heating chamber in various shapes and types -Heated objects with different amounts can be heated with high efficiency.

In particular, the fifth aspect of the invention relates to a plurality of regular polygon vertices having a center on one axis on which a symmetrical center point of the substantially symmetrically arranged feeding portion combination of any one of the first to third aspects of the invention exists. The power feeding unit is arranged at all positions, and the distribution of the strong directional microwave power generated by the mutual interference of the microwaves radiated from the feeding unit combination arranged at each vertex of the regular polygon is superimposed. Heating objects with different shapes, types, and quantities can be efficiently heated by combining them, dispersing them at multiple locations, and efficiently absorbing microwaves radiated into the heating chamber. Can do.

  The sixth aspect of the invention is, in particular, the position of the vertex of a regular polygon having a center on one axis where the symmetrical center point of the substantially symmetrically arranged feeding unit combination of any one of the first to third aspects exists. It is configured to mix power feeding parts arranged at all and power feeding parts arranged at positions different from the substantially symmetrical arrangement, and is generated by mutual interference of microwaves radiated from power feeding part combinations arranged at regular polygon vertices. The microwave power distribution can be easily controlled by complementing the strong directional microwave power distribution with the microwave power radiated from multiple power supply units arranged at different positions. -Heated objects with different amounts can be heated with high efficiency.

In the seventh aspect of the invention, in particular, the radiation direction of the microwave radiated from the power supply unit of the combination arranged substantially symmetrically of the first invention to the heating chamber is perpendicular to the plane connecting the power supply unit combinations, It is configured to be substantially symmetrical, strengthening the mutual interference between the power feeding parts of the combination arranged substantially symmetrically, effectively controlling the distribution of the generated microwave power, and the microwave radiated to the heating chamber The object to be heated can be efficiently absorbed, and the object to be heated of various shapes, types, and amounts can be heated with high efficiency.

In the eighth aspect of the invention, in particular, for each of the power feeding unit combinations arranged substantially symmetrically according to the first invention, the power feeding unit combinations are arranged so as to be shifted in one axial direction where the substantially symmetrical center point of the power feeding unit combination exists. Yes, if the power feeding unit cannot be arranged in the same plane due to unevenness on the bottom wall surface of the heating chamber, the influence of the position can be minimized by shifting the arrangement for each power feeding unit combination, and the microwave radiated into the heating chamber can be efficiently used Therefore, the object to be heated can be absorbed efficiently, and the object to be heated of various shapes, types and amounts can be heated with high efficiency.

In the ninth invention, in particular, the control unit according to any one of the first to eighth inventions is configured to simultaneously control a plurality of combinations of power feeding units arranged substantially symmetrically with the same phase difference. By selecting and controlling multiple combinations of power feeding units that control the relative phase, the direction of moving the distribution position of the microwave power can be manipulated in more detail, and the object to be heated in various shapes, types, and quantities Can be optimally heated.

In the tenth invention, in particular, the control unit according to any one of the first to eighth inventions is configured to control a plurality of combinations of power feeding units arranged substantially symmetrically with different phase differences. Yes, by selecting multiple combinations of power feeding units that control the relative phase and simultaneously controlling with different phase differences, the direction of moving the distribution position of the microwave power can be operated in a wider range, and various shapes, types, and quantities Can be heated optimally.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a microwave processing apparatus according to the first embodiment of the present invention.

In FIG. 1, the microwave generation unit includes oscillation units 1 a and 1 c configured using semiconductor elements, power distribution units 2 a and 2 c that distribute the outputs of the oscillation units 1 a and 1 c, and outputs of the power distribution units 2 a and 2 c. Amplifying units 4a to 4d configured using semiconductor elements to be amplified, power feeding units 5a to 5d for radiating microwave outputs amplified by the amplifying units 4a to 4d into the heating chamber, and power distribution units 2a and 2c and amplifying unit 4a Are inserted into the microwave propagation path that connects the power supply sections 5a to 5d and the phase variable sections 3a to 3d that are inserted into the microwave propagation path that connects to 4d and generates an arbitrary phase difference between the input and output. According to the reflected power detected by the power detectors 6a to 6d and the power detectors 6a to 6d for detecting the microwave reflected power reflected from the power feeders 5a to 5d in the direction of the amplifiers 4a to 4d. Fubu 1a, are constituted by a control unit 7 for controlling the phase of the oscillation frequency and the phase variable parts 3a~3d of 1c.

  In addition, the microwave processing apparatus of the present invention has a heating chamber 8 having a substantially rectangular parallelepiped structure for storing the object 9 to be heated, and the heating chamber 8 is opened and closed to store the wall surface and the object 9 to be heated. The microwave to be supplied is confined in the opening / closing door (not shown) and the mounting table 12 on which the object to be heated 9 is mounted. Then, the microwave output generated in the oscillation units 1 a and 1 c is propagated, and the four power supply units 5 a to 5 d that radiate and supply the heating chamber 8 are all arranged on the bottom wall surface of the wall that constitutes the heating chamber 8. .

  The amplifying units 4a to 4d constitute a circuit with a conductor pattern formed on one surface of a dielectric substrate made of a low dielectric loss material, and operate the semiconductor elements that are the amplifying elements of the amplifying units 4a to 4d satisfactorily. Therefore, matching circuits are arranged on the input side and output side of each semiconductor element. The power distribution units 2a and 2c may be in-phase distributors that do not cause a phase difference between outputs such as a Wilkinson distributor, or may have a phase difference between outputs such as a branch line type or a rat race type. It may be the resulting distributor.

  By the power distribution units 2a and 2c, approximately 1/2 of the microwave power input from the oscillation units 1a and 1c is propagated to the respective outputs. The phase variable units 3a to 3d are configured using a variable capacitance element whose capacitance changes according to the applied voltage, and each phase variable range is a range from 0 degrees to about 180 degrees. As a result, the phase difference of the microwave power output from the phase variable units 3a to 3d can be controlled in the range of 0 degrees to ± 180 degrees.

  The power detection units 6a to 6d extract microwaves reflected from the power supply units 5a to 5d in the direction of the amplification units 4a to 4d, so-called reflected wave power. The power coupling degree is, for example, about 40 dB, and the reflected power About 1/10000 of the amount of power is extracted. The power signals are rectified by a detection diode (not shown), smoothed by a capacitor (not shown), and the output signal is input to the control unit 7.

  The control part 7 is based on the heating information of the to-be-heated object 9 which a user inputs directly, or the heating information obtained from the heating state of the to-be-heated object 9 during heating, and the detection information of the electric power detection parts 6a-6d. In the heating chamber 8, the driving power supplied to the oscillation units 1a and 1c and the amplification units 4a to 4d, which are constituent elements of the microwave generation unit, and the voltage supplied to the phase variable units 3a to 3d are controlled. The stored object 9 is heated optimally.

  About the microwave processing apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  First, the object to be heated 9 is stored in the heating chamber 8, the heating condition is input from an operation unit (not shown), and the heating start key is pressed. In response to the control output signal of the control unit 7 that has received the heating start signal, the microwave generation unit starts its operation. The control means 7 operates a drive power supply (not shown) to supply power to the oscillation units 1a and 1c. At this time, the initial oscillation frequency of the oscillation units 1a and 1c is supplied with a voltage signal set to 2400 MHz, for example, and oscillation starts. When the oscillating units 1a and 1c are operated, their outputs are distributed approximately ½ each by the power distributing units 2a and 2c, resulting in four microwave power signals. Thereafter, the drive power supply is controlled to operate the amplification units 4a to 4d.

The microwave power signals are output to the power feeding units 5 a to 5 d through the amplification units 4 a to 4 d and the power detection units 6 a to 6 d that operate in parallel, and are radiated into the heating chamber 8. When 100% of the microwave power supplied into the heating chamber 8 is absorbed by the object 9 to be heated, the reflected power from the heating chamber 8 becomes 0 W, but depending on the type, shape and amount of the object 9 to be heated, The impedance of the heating chamber 8 changes, and microwave reflected power propagating from the power supply units 5a to 5d in the direction of the amplification units 4a to 4d is generated due to misalignment with the microwave power supply side.

  The power detectors 6 a to 6 d detect the microwave reflected power and send a detection signal proportional to the reflected power amount to the control unit 7. The control unit 7 controls the oscillation units 1a and 1c and the phase variable units 3a to 3d under the conditions of the oscillation frequency and the phase difference at which the reflected power is minimized so that an output corresponding to the input heating condition can be obtained. To control the oscillation output. The microwaves having the oscillation frequency according to the control of the control unit 7 become power according to the control in the amplification units 4a to 4d, and are supplied to the respective power feeding units 5a to 5d with a phase difference corresponding to the control. 8 is emitted.

  Next, the relationship between the arrangement of the power feeding unit and the distribution of the microwave power will be described.

  FIG. 2 is a perspective view of the microwave processing apparatus according to the first embodiment of the present invention.

  In FIG. 2, four power feeding parts 5 a to 5 d are arranged on all the vertices of the regular square arrangement 14 on the bottom wall surface of the heating chamber 8 below the mounting table 12, and the power feeding parts 5 a and 5 b and the power feeding parts 5 c and 5 d. However, it is substantially symmetrical with respect to the center point 10 on the heating chamber central axis 13 at a distance of a half wavelength or less. Further, the microwave radiation directions of the power feeding units 5a and 5b are substantially symmetrical with respect to a plane perpendicular to the straight line connecting the combinations of the power feeding units 5a and 5b, and the excitation direction 11a of the radiation microwave electric field is set to be the same direction. Then, the microwaves from the power feeding units 5 a and 5 b have substantially symmetric radiation characteristics with respect to the heating chamber central axis 13. The low-power microwaves radiated from the power supply units 5a and 5b having substantially symmetric radiation characteristics become high power synthesized by mutual interference, and a microwave distribution with strong directivity is generated in the heating chamber.

  When the relative phase between the power feeding parts 5a and 5b is shifted, the mutual interference position of the microwaves radiated from the power feeding parts 5a and 5b fluctuates in the line direction connecting the power feeding parts 5a and 5b, and the position of the strong microwave distribution Can be operated. Similarly, the power feeding units 5c and 5d are installed so that the microwave radiation directions are substantially symmetric and the excitation directions 11c are the same direction, so that they have substantially symmetric radiation characteristics, and the positions of the microwave distributions generated by mutual interference are relative phase. Can be operated by control.

  The characteristics of the microwave distribution obtained by synthesizing all the four power feeding units 5a to 5d are determined by the directions of the excitation directions 11a and 11c. When the excitation directions 11a and 11c are orthogonal to each other, the microwave distribution generated by the mutual interference of the power feeding units 5a and 5b and the microwave distribution generated by the mutual interference of the power feeding units 5c and 5d have almost no mutual interference. Heating is performed by simply superimposing the microwave distributions of the power feeding units 5a and 5b and the power feeding units 5c and 5d. When the excitation directions 11a and 11c are not orthogonal to each other, mutual interference corresponding to the deviation of the angle from the right angle occurs, and the microwave distributions of the power feeding units 5a and 5b and the power feeding units 5c and 5d are combined, and more directivity is achieved. A strong microwave distribution is generated in the heating chamber 8.

As described above, the power feeding units 5a to 5d are arranged at the apexes of the regular tetragonal arrangement 14, and the frequency and the output value are substantially matched in each combination of the power feeding units 5a and 5b and the power feeding units 5c and 5d. Since the radiation characteristics are symmetric, the position of the microwave distribution can be manipulated by performing the same control and different control simultaneously on the relative phase in each combination of the power feeding units 5a and 5b and the power feeding units 5c and 5d. By superposing or synthesizing both microwave distributions, the position of the strong microwave distribution can be manipulated over a wide range in a two-dimensional direction. By operating in this way, it is possible to operate a strong microwave distribution, the microwave radiated into the heating chamber 8 can be efficiently absorbed by the article 9 to be heated, and various shapes, types and amounts of objects to be covered are different. The heated object 9 can be optimally heated with high efficiency.

  In this embodiment, the configuration of power supply at four points is shown. However, the present embodiment is not limited to this embodiment, and the same applies when the number of power supply units 5a to 5d is increased or the number of regular polygons is increased. Mutual interference corresponding to each excitation direction angle occurs, a microwave distribution obtained by synthesizing or simply superimposing the microwave distributions can be generated in the heating chamber 8, and similarly by performing relative phase control, The position of the generated microwave distribution can be manipulated. When the power feeding parts 5a to 5d cannot be arranged in the same plane due to the uneven shape of the bottom wall surface of the heating chamber 8, the power feeding parts 5a and 5b and the power feeding parts 5c and 5d arranged substantially symmetrically are shifted in the direction of the arrangement center axis. By rearranging them, the influence of the difference in position can be minimized.

  As described above, the microwave processing apparatus according to the present invention arranges all the power feeding units at even locations and at least four locations substantially symmetrically on the bottom wall surface of the heating chamber, and controls the phase difference between the substantially symmetrically arranged power feeding units. Since the microwave distribution can be manipulated, the present invention can be applied to uses such as a heating device using a dielectric heating such as a microwave oven, a garbage processing machine, or a microwave power source of a plasma power source as a semiconductor manufacturing apparatus.

Configuration diagram of microwave processing apparatus according to Embodiment 1 of the present invention The perspective view of the microwave processing apparatus in Embodiment 1 of this invention

DESCRIPTION OF SYMBOLS 1a, 1c Oscillation part 2a, 2c Power distribution part 3a-3d Phase variable part 4a-4d Amplification part 5a-5d Power supply part 6a-6d Power detection part 7 Control part 8 Heating chamber 9 Heated object 10 Center point 11a, 11c Excitation Direction 12 Mounting table 13 Heating chamber central axis 14 Regular square arrangement

Claims (10)

A heating chamber that accommodates an object to be heated; an oscillation unit; a power distribution unit that distributes and outputs the output of the oscillation unit; and a phase variable unit that varies at least one output phase of the power distribution unit; An amplifying unit that amplifies the output of each of the power distribution unit and / or the phase variable unit, a feeding unit that supplies the output of the amplifying unit to the heating chamber, and a reflection from each feeding unit toward the amplifying unit A power detection unit for detecting the microwave power, and a control unit for controlling the oscillation frequency of the oscillation unit and the phase amount of the phase variable unit,
The power feeding unit is arranged at an even number of four or more places on the bottom wall surface of the heating chamber, and a plurality of combinations of the two power feeding units are provided approximately symmetrically with respect to a point on one axis. The lines connecting the two power supply units constituting the crossing are arranged so as to intersect each other in the combination of the plurality of power supply units, and the combination of the power supply units matches the excitation direction of the microwave electric field radiated to the heating chamber. Arranged,
The microwave processing apparatus configured to relatively control the phase of the microwave supplied from the power feeding unit between combinations of the plurality of power feeding units. The microwave processing apparatus according to claim 1, wherein the symmetrical center point of the power feeding unit combinations arranged substantially symmetrically is provided on a vertical axis passing through a substantially center of a heated object installation horizontal plane of the heating chamber. 3. The power supply unit according to claim 1, wherein the power supply units are arranged at all vertex positions of one regular polygon having a center on one axis where a symmetrical center point of a combination of power supply units arranged substantially symmetrically exists. Microwave processing equipment. The microwave processing apparatus according to claim 1, wherein the plurality of power feeding units are arranged at a position of a half wavelength or less from a substantially symmetrical arrangement center point. 4. The power feeding unit according to any one of claims 1 to 3, wherein the power feeding units are arranged at all vertex positions of a plurality of regular polygons having a center on one axis where a symmetrical center point of a combination of power feeding units arranged substantially symmetrically exists. The microwave processing apparatus of Claim 1. A power supply unit arranged at all vertex positions of a regular polygon having a center on one axis where a symmetrical center point of a combination of power supply units arranged substantially symmetrically exists, and the power supply arranged at a position different from the substantially symmetrical arrangement The microwave processing apparatus of any one of Claim 1 to 3 made into the structure which mixes a part. The radiation direction of the microwave radiated to the heating chamber from the power feeding unit of the combination arranged substantially symmetrically is configured to be substantially symmetrical with respect to a plane perpendicular to a straight line connecting the power feeding unit combinations. The microwave processing apparatus as described. The microwave processing device according to claim 1, wherein each of the power feeding unit combinations arranged substantially symmetrically is arranged to be shifted in one axial direction in which a substantially symmetrical arrangement center point of the power feeding unit combination exists. The microwave processing apparatus according to any one of claims 1 to 8, wherein the control unit is configured to simultaneously control a plurality of combinations of the power feeding units arranged substantially symmetrically with the same phase difference. The microwave processing apparatus according to any one of claims 1 to 8, wherein the control unit is configured to control a plurality of combinations of power feeding units arranged substantially symmetrically with different phase differences.