Reflection box and antenna device

Abstract

To provide a reflective box which allows for performing highly accurate EMS tests in a wider frequency band.SOLUTION: A reflective box having an electromagnetic agitator is provided, comprising a first agitator blade and a holder provided on a first wall surface of the reflective box to extend in a first direction crossing the first wall surface and hold the first agitator blade. The first agitator blade is electrically insulated from the first wall surface.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a reflector box and an antenna device. [Background technology]

[0002] Research and development is being conducted on technology to use a reverberation chamber to perform EMS (Electromagnetic Susceptibility) testing, which is an electromagnetic resistance test for vehicles and electronic devices installed in vehicles.

[0003] A reverberation chamber consists of a metal cavity resonator and an electromagnetic stirrer. The cavity resonator is responsible for generating an electric field in the reverberation chamber using the resonance phenomenon. The distribution of the electric field strength generated by the cavity resonator exhibits variations in strength due to the dimensions of the cavity resonator. In other words, the distribution of the electric field strength generated by the cavity resonator is uneven. For this reason, the electromagnetic stirrer stirs the electromagnetic waves inside the cavity resonator, making the distribution of the electric field strength generated by the cavity resonator closer to a uniform distribution. When applied to EMS testing, a uniform electric field can be irradiated onto the test specimen, making the reverberation chamber a test device with high test quality.

[0004] It is known that the resonant frequency of the cavity resonator in such a reverberation chamber is inversely proportional to the dimensions of the resonator. For this reason, in EMS testing, the lower the frequency of the electric field generated using the resonance phenomenon, the larger the volume of the reverberation chamber had to be.

[0005] For example, in an EMS test of a vehicle conducted in an anechoic chamber, an electric field in a frequency band including a frequency of approximately 10 kHz is irradiated onto the vehicle. If an EMS test using an electric field in such a frequency band is to be conducted inside a reverberation chamber, the dimensions of the reverberation chamber would be approximately 10 km. A reverberation chamber of such dimensions is undesirable because it limits the degree of freedom in where it can be installed. For this reason, in recent years, there has been a demand for reverberation chambers that are equipped with equipment capable of conducting EMS tests using the relevant frequency band and are large enough to accommodate a test specimen.

[0006] A test device (strip line device) called a Transmission Line System (TLS) is known as a test device that irradiates a test specimen with an electric field in a predetermined low frequency band in an anechoic chamber (see Patent Document 1). The low frequency band refers to a frequency band including frequencies below the lowest usable frequency (LUF) at which the test specimen functions as a reverberation chamber, a frequency band including frequencies below the lowest resonant frequency of the reverberation chamber, etc. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-072786 Summary of the Invention [Problem to be solved by the invention]

[0008] Also known as test devices for irradiating a test specimen with such a low-frequency electric field in an anechoic chamber are test devices that irradiate the electric field from an antenna such as a log periodic antenna. Each of these test devices can irradiate the test specimen with the low-frequency electric field as an electric field of uniform strength in an anechoic chamber.

[0009] However, when these test devices are used in a reverberation chamber, electric fields with frequencies lower than the lowest-order resonant frequency of the reverberation chamber can cause resonance, even though the frequency is lower than the lowest-order resonant frequency of the reverberation chamber. This is undesirable because it leads to a loss of uniformity in the electric field strength. Furthermore, when the frequency of the electric field is lower than the lowest-order resonant frequency of the reverberation chamber, the electromagnetic stirrer cannot stir the electric field. Therefore, in such cases, it is difficult to reduce the variation in the electric field strength of the reverberation chamber using the electromagnetic stirrer.

[0010] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a reflection chamber and an antenna device that can perform EMS testing with high accuracy over a wider frequency band. [Means for solving the problem]

[0011] One aspect of the present invention is a reflecting box equipped with an electromagnetic stirrer, the electromagnetic stirrer comprising a first stirring blade and a holder provided on a first wall surface of the reflecting box, extending in a first direction intersecting the first wall surface, and holding the first stirring blade, wherein the first stirring blade is electrically insulated from the first wall surface.

[0012] Another aspect of the present invention is a reflecting box equipped with an electromagnetic stirrer, the electromagnetic stirrer comprising a first stirring blade, a second stirring blade, and a holder provided on a first wall surface of the reflecting box, extending in a first direction intersecting the first wall surface, and holding the first stirring blade and the second stirring blade side by side in the first direction, wherein the first stirring blade is electrically insulated from the second stirring blade.

[0013] Another aspect of the present invention is an antenna device including the above-described reflector box. [Effects of the Invention]

[0014] According to the present invention, it is possible to perform EMS testing with high accuracy over a wider frequency band. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing an example of the configuration of a reflector box 1 according to an embodiment. [Figure 2] FIG. 2 is a diagram showing a first configuration example of an electromagnetic stirrer 13. [Figure 3] FIG. 2 is a diagram showing an example of the configuration of a coupling C1. [Figure 4] 10A and 10B are diagrams showing another example of the configuration of the coupling C1. [Figure 5] 10 is a diagram showing still another example of the configuration of the coupling C1. FIG. [Figure 6] FIG. 2 is a diagram showing an example of the configuration of a bearing B1. [Figure 7] 10A and 10B are diagrams showing another example of the configuration of the bearing B1. [Figure 8] 10 is a diagram showing yet another example of the configuration of the bearing B1. FIG. [Figure 9] 10 is a diagram showing an example of a gap SP formed in a first agitating blade 131. FIG. [Figure 10] FIG. 10 is a diagram showing an example of the state of a first agitating blade 131 fixed to a flange F1. [Figure 11] FIG. 10 is a diagram showing another example of the state of the first agitating blade 131 fixed to the flange F1. [Figure 12] FIG. 10 is a diagram showing yet another example of the state of the first agitating blade 131 fixed to the flange F1. [Figure 13] 10 is a diagram illustrating the electric field intensity inside the reflector box 1 when the reflector box 1 is equipped with a conventional electromagnetic stirrer instead of the electromagnetic stirrer 13A. FIG. [Figure 14] 3 is a diagram illustrating the electric field intensity inside the reflector box 1. FIG. [Figure 15] FIG. 10 is a diagram showing a second configuration example of the electromagnetic stirrer 13. [Figure 16] FIG. 10 is a diagram showing a third configuration example of the electromagnetic stirrer 13. [Figure 17] FIG. 10 is a diagram showing a fourth configuration example of the electromagnetic stirrer 13. [Figure 18] FIG. 10 is a diagram showing a fifth configuration example of the electromagnetic stirrer 13. [Figure 19] FIG. 10 is a diagram showing a sixth configuration example of the electromagnetic stirrer 13. [Figure 20] FIG. 10 is a diagram showing a seventh configuration example of the electromagnetic stirrer 13. [Figure 21] 21 is a diagram showing a first modification of the configuration of the support body SB shown in FIG. 20. FIG. [Figure 22] 21 is a diagram showing a second modification of the configuration of the support body SB shown in FIG. 20. FIG. [Figure 23] 21 is a diagram showing a third modified example of the configuration of the support body SB shown in FIG. 20. FIG. [Figure 24] FIG. 10 is a diagram showing an eighth configuration example of the electromagnetic stirrer 13. [Figure 25] FIG. 10 is a diagram showing a ninth configuration example of the electromagnetic stirrer 13. [Figure 26] This is a table showing a list of materials used for insulating bushings such as bushing BS2, insulating screws (or bolts) such as fastener SC, insulating spacers such as spacer S1, insulating bases such as bearing fixing base B13, etc. [Figure 27] 7 is a table showing a list of materials used in bearings made entirely of insulating materials, such as the bearing B1 shown in FIG. 6. [Figure 28] 8 is a table showing a list of materials used for the insulating coating of the bearing B1 shown in FIG. 7. [Figure 29] 10 is a table showing a list of materials used for the insulating holder A1 and the like. DETAILED DESCRIPTION OF THE INVENTION

[0016] <Embodiment> Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience of explanation, the strength of an electric field will be referred to as "electric field strength" below. Therefore, the strength of an electric field within a certain region will be referred to as "electric field strength within the region" below.

[0017] <Configuration of the reflection box> First, the configuration of a reflecting box 1 according to the embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of a reflecting box 1 according to the embodiment.

[0018] The reflective chamber 1 is a container in which EMS tests are performed on various electronic devices. For ease of explanation, the electronic devices that are the targets of the EMS tests will be referred to as test pieces in the following description.

[0019] In EMS testing, a simulated electromagnetic environment is created in which the test specimen is assumed to be actually used. The EMS test then tests whether the test specimen operates normally in the simulated electromagnetic environment. In this type of EMS test, the more uniform the electric field strength within the area containing the test specimen, the more accurate the test results. Here, the uniformity of the electric field strength within a certain area is expressed by a quantity (e.g., standard deviation, variance, etc.) that indicates the variance of the electric field strength within that area. In other words, the smaller the quantity that indicates the variance of the electric field strength within that area, the higher the uniformity of the electric field strength within that area.

[0020] The reflective chamber 1 includes, for example, a cavity resonator 11, a test device 12, and an electromagnetic stirrer 13. The reflective chamber 1 may not include the test device 12. Although the test device 12 is configured integrally with the reflective chamber 1 in FIG. 1, it may be configured separately from the test device 12. When the reflective chamber 1 and the test device 12 are configured separately, the reflective chamber 1 and the test device 12 form an antenna device. The reflective chamber 1 may also include other members, other devices, etc. in addition to the cavity resonator 11, the test device 12, and the electromagnetic stirrer 13.

[0021] The cavity resonator 11 is a metal housing capable of accommodating a test specimen. The cavity resonator 11 resonates an electric field having a frequency equal to or higher than the lowest-order resonance frequency of the resonator box 1. Note that part of the wall surface of the cavity resonator 11 may be made of an insulator. In the following description, for convenience of explanation, the lowest-order resonance frequency of the resonator box 1 will be referred to as the lowest-order resonance frequency.

[0022] The test device 12 is a device that irradiates an electric field of a predetermined frequency band to a test piece placed in the cavity resonator 11. The test device 12 is communicably connected to the control device 14 and is controlled by the control device 14. In the example shown in FIG. 1 , the test device 12 is configured separately from the control device 14. However, the test device 12 may be configured integrally with the control device 14.

[0023] The control device 14 is, for example, but not limited to, a notebook PC (Personal Computer), a desktop PC, a workstation, a tablet PC, a multi-function mobile phone terminal (smartphone), a mobile phone terminal, a PDA (Personal Digital Assistant), etc. The control device 14 receives operations from a user and controls the test device 12 in accordance with the received operations.

[0024] The test device 12 includes a signal generator 121 , an amplifier 122 , a directional coupler 123 , an agitator controller 124 , a power meter 125 , and an antenna 126 .

[0025] Signal generator 121 outputs an AC voltage signal of a predetermined frequency to amplifier 122 in response to control from control device 14. Below, as an example, a case will be described in which signal generator 121 outputs an AC voltage signal of a frequency lower than the lowest-order resonance frequency to amplifier 122.

[0026] The amplifier 122 amplifies the amplitude of the AC voltage signal obtained from the signal generator 121 and outputs the AC voltage signal after the amplitude has been amplified to the directional coupler 123 .

[0027] The directional coupler 123 outputs the AC voltage signal acquired from the amplifier 122 to the power measuring device 125, and also outputs the AC voltage signal to the antenna 126 as an RF signal.

[0028] The agitator controller 124 outputs a control signal to the motor M, which controls the motor M that rotates the electromagnetic agitator 13, in accordance with the power measured by the power meter 125 and the control from the control device 14.

[0029] The power meter 125 measures the power based on the AC voltage signal obtained from the directional coupler 123. The power meter 125 outputs power information indicating the measured power to the control device 14.

[0030] The antenna 126 irradiates an electric field corresponding to the RF signal acquired from the directional coupler 123 toward the test specimen. The antenna 126 is installed in a position where the electric field can be irradiated toward the test specimen. In this example, the frequency of the RF signal is lower than the lowest-order resonance frequency. In this case, the antenna 126 irradiates an electric field of a frequency lower than the lowest-order resonance frequency toward the test specimen.

[0031] In the example shown in FIG. 1, the antenna 126 is installed in an area directly above a work area WV on the ceiling surface of the cavity resonator 11. The work area WV is an area within the cavity resonator 11 where a test subject is installed. In other words, the work area WV is an area within the reverberation chamber 1 where an EMS test is performed. In the example shown in FIG. 1, a test subject TM is installed within the work area WV. The test subject TM is an example of an electronic device to be tested.

[0032] The electromagnetic stirrer 13 stirs the electromagnetic waves inside the reflective chamber 1. This allows the reflective chamber 1 to reduce variations in the electric field strength inside the working space WV.

[0033] The electromagnetic stirrer 13 has one or more stirring blades and is rotated by a motor M. The motor M that rotates the electromagnetic stirrer 13 may be provided in the reflection box 1, may be provided in the electromagnetic stirrer 13, or may not be provided in either the reflection box 1 or the electromagnetic stirrer 13. In addition, in FIG. 1, in order to simplify the drawing, various mechanisms, gears, etc. that transmit the driving force of the motor M to the electromagnetic stirrer 13 are omitted.

[0034] Here, an electric field having a frequency lower than the lowest-order resonance frequency may cause a resonance phenomenon within the reverberation chamber 1, even though the frequency is lower than the lowest-order resonance frequency. This is undesirable because it leads to a loss of uniformity in the electric field strength within the working space WV. Such a resonance phenomenon occurs because the electromagnetic stirrer 13 itself functions as a capacitor, or the combination of the electromagnetic stirrer 13 and the cavity resonator 11 functions as a capacitor. For example, if the electromagnetic stirrer 13 has only one stirring blade, the space between that one stirring blade and the wall surface of the cavity resonator 11 functions as a capacitor. That is, in this case, the combination of the electromagnetic stirrer 13 and the cavity resonator 11 functions as a capacitor. Furthermore, if the electromagnetic stirrer 13 has two or more stirring blades, the space between those two or more stirring blades and the wall surface of the cavity resonator 11 also functions as a capacitor, and the space between those two or more stirring blades also functions as a capacitor. That is, in this case, the combination of the electromagnetic stirrer 13 and the cavity resonator 11 functions as a capacitor, and the electromagnetic stirrer 13 itself also functions as a capacitor.

[0035] The presence of such a capacitor causes an LC resonance phenomenon. For example, if a certain stirring blade and a certain wall surface inside the cavity resonator 11 function as a capacitor, the member connecting the stirring blade and the wall surface functions as an inductor, forming an LC resonance circuit. Also, for example, if two stirring blades function as a capacitor, the member connecting the two stirring blades functions as an inductor, forming an LC resonance circuit. Due to the resonance phenomenon of the LC resonance circuit formed in this way, the distribution of the electric field strength at frequencies lower than the lowest resonance frequency may become uneven.

[0036] Therefore, the electromagnetic stirrer 13 has at least one of a configuration for insulating the stirrers from each other and a configuration for insulating the stirrer from the wall surface inside the cavity resonator 11, thereby suppressing at least a part of the resonance phenomenon caused by such an LC resonant circuit. As a result, the reverberation chamber 1 equipped with the electromagnetic stirrer 13 can make the distribution of the electric field strength within the working space WV more uniform over a wider frequency band. As a result, the reverberation chamber 1 can perform an EMS test with high accuracy over a wider frequency band. Furthermore, the reverberation chamber 1 can generate an electric field with uniform electric field strength within the working space WV using the above-mentioned test device 12 without increasing the volume of the reverberation chamber 1. Therefore, the reverberation chamber 1 equipped with the test device 12 and the electromagnetic stirrer 13 (or an antenna device equipped with the reverberation chamber 1 equipped with the electromagnetic stirrer 13 and the test device 12) can perform a highly accurate EMS test over a wider frequency band without increasing the volume of the cavity resonator 11.

[0037] A specific example of the configuration of the electromagnetic stirrer 13 will be described below.

[0038] <Electromagnetic stirrer configuration example 1> A first configuration example of the electromagnetic stirrer 13 will be described below with reference to FIG. 2. FIG. 2 is a diagram showing the first configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in FIG. 2 will be referred to as electromagnetic stirrer 13A in the following description. The arrows shown in FIG. 2 indicate the up and down directions in FIG. 2. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity. As an example, a case will be described below in which the electromagnetic stirrer 13A has two stirring blades.

[0039] The electromagnetic stirrer 13A is installed between two of the wall surfaces within the cavity resonator 11, that is, the first wall surface W1 and the second wall surface W2.

[0040] The first wall surface W1 may be any wall surface inside the cavity resonator 11. In the example shown in FIG. 2, the first wall surface W1 is an upper wall surface among the wall surfaces inside the cavity resonator 11, that is, a ceiling surface inside the cavity resonator 11.

[0041] The second wall surface W2 may be any wall surface different from the wall surface used as the first wall surface W1 among the wall surfaces inside the cavity resonator 11. In the example shown in Fig. 2, the second wall surface W2 is a wall surface on the lower side among the wall surfaces inside the cavity resonator 11, i.e., the floor surface inside the cavity resonator 11. Note that when the electromagnetic stirrer 13 is rotated by the motor M via a universal joint or the like, the second wall surface W2 may be the same wall surface as the first wall surface W1.

[0042] In the example shown in FIG. 2, the electromagnetic stirrer 13A is installed between the first wall surface W1 and the second wall surface W2 so that the rotation axis of the electromagnetic stirrer 13A (i.e., the rotation axis A0 of the motor M) is parallel to the direction of gravity.

[0043] The electromagnetic stirrer 13A includes a holder A1, a first stirring blade 131, a flange F1, a second stirring blade 132, a flange F2, a coupling C1, a coupling C2, and a bearing B1.

[0044] The holder A1 is, for example, a metal shaft extending in a first direction. The first direction is a direction parallel to the axial direction of the rotation shaft of the electromagnetic stirrer 13A, which is rotated by the drive of the motor M. In the example shown in FIG. 2, the first direction is a direction perpendicular to the first wall W1, extending from the first wall W1 to the second wall W2, i.e., the direction of gravity. The holder A1 may be composed of multiple shafts or a single shaft. The holder A1 may also be made of a conductive material other than metal, instead of metal.

[0045] A first stirring blade 131, a second stirring blade 132, a coupling C1, a coupling C2, and a bearing B1 are fixed to the holder A1 in the order of coupling C1, first stirring blade 131, coupling C2, second stirring blade 132, and bearing B1 from top to bottom.

[0046] For ease of explanation, the combination of part A11, which is located above the first agitating blade 131, the coupling C1, and the flange F1 will be referred to as part H1 in the following description. Also, for ease of explanation, the combination of part A12, which is located below the second agitating blade 132, the bearing B1, and the flange F2 will be referred to as part H2 in the following description. Also, for ease of explanation, the combination of part A13, which is located between the first agitating blade 131 and the second agitating blade 132, and the coupling C2 will be referred to as part H3 in the following description. Some or all of the holders H1 to H3 may be configured separately from one another, or may be configured integrally.

[0047] The portion A11 is connected to the rotating shaft A0 of the motor M via a coupling C1 of the holder H1. Therefore, the holder A1 rotates in response to the rotation of the rotating shaft A0 of the motor M. In the example shown in FIG. 2, the rotating shaft A0 of the motor M is omitted for simplicity. The holder H1 may be configured to include the rotating shaft A0 of the motor M. In this case, the rotating shaft A0 of the motor M is an example of a third holder electrically connected to the first wall surface. In this case, the portion A11 is an example of a fourth holder connected to the first agitating blade. The holder H1 may also be configured to include a member (e.g., a shaft) that connects the rotating shaft A0 of the motor M to the coupling C1. In this case, this member is an example of a third holder electrically connected to the first wall surface. In this case, the portion A11 is an example of a fourth holder connected to the first agitating blade.

[0048] The coupling C1 connects the rotary shaft A0 of the motor M to the part A11.

[0049] The flange F1 is a metal flange to which the first agitating blade 131 is fixed, and may be a flange of any shape. The flange F1 is fixed to the part A11 with fasteners such as screws. The flange F1 may be configured as an integral part with the part A11. The flange F1 may also be configured as a separate part from the holder H1. The flange F1 may also be configured to be included in the holder H3 instead of the holder H1. In this case, the first agitating blade 131 is held by the holder H3. The flange F1 may also be made of a conductor other than metal instead of metal.

[0050] The first agitating blade 131 is, for example, a rectangular flat plate-shaped member made of metal. The first agitating blade 131 is held by the holder H1 via a flange F1. That is, the first agitating blade 131 is fixed to the flange F1. The electromagnetic agitator 13A may not have a flange F1. In this case, the first agitating blade 131 is held by the holder H1 by being fixed to the part A11. The first agitating blade 131 may also be formed integrally with at least a part of the members that make up the holder H1. The first agitating blade 131 may also be made of a conductor other than metal instead of metal.

[0051] When the first agitating blade 131 has a rectangular plate shape, the first agitating blade 131 is fixed to the flange F1 so as to be oblique to the holder A1. This allows the first agitating blade 131 to agitate the electromagnetic waves in the cavity resonator 11 in accordance with the rotation of the electromagnetic agitator 13A. Note that the shape of the first agitating blade 131 may be other shapes instead of the rectangular plate shape. In this case, the first agitating blade 131 is fixed to the flange F1 so as to be able to agitate the electromagnetic waves in the cavity resonator 11 in accordance with the rotation of the electromagnetic agitator 13A.

[0052] The part A13 is divided into two parts, an upper part and an lower part, and these two parts are connected by a coupling C2. For ease of explanation, the upper part of these two parts will be referred to as the holder A131 and the lower part of these two parts will be referred to as the holder A132.

[0053] The coupling C2 is a coupling that connects the holder A131 and the holder A132.

[0054] The holder A131 is connected to the part A11. The holder A131 may be configured integrally with the part A11 or may be configured separately from the part A11. When the holder A131 is configured separately from the part A11, the holder A131 includes a coupling or the like that connects the holder A131 and the part A11.

[0055] The holder A132 is connected to the portion A12. The holder A132 may be configured integrally with the portion A12 or may be configured separately from the portion A12. When the holder A132 is configured separately from the portion A12, the holder A1 includes a coupling or the like that connects the holder A132 and the portion A12.

[0056] The portion A12 is connected to the second wall surface W2 via the bearing B1, so that the second wall surface W2 does not hinder the rotation of the holder A1 caused by the motor M.

[0057] The bearing B1 is a thrust bearing that supports the holder A1 that rotates around the rotation axis of the motor M.

[0058] The flange F2 is a metal flange to which the second agitating blade 132 is fixed, and may be of any shape. The flange F2 is fixed to the portion A12 with fasteners such as screws. The flange F2 may be configured as an integral part of the portion A12. The flange F2 may also be configured as a separate part from the holder H2. The flange F2 may also be configured to be included in the holder H3 instead of the holder H2. In this case, the second agitating blade 132 is held by the holder H3. The flange F2 may also be made of a conductor other than metal instead of metal.

[0059] The second agitating blade 132 is, for example, a rectangular flat plate-shaped member made of metal. The second agitating blade 132 is held by the holder H2 via a flange F2. That is, the second agitating blade 132 is fixed to the flange F2. The electromagnetic agitator 13A may not have a flange F2. In this case, the second agitating blade 132 is held by the holder H2 by being fixed to the portion A12. The second agitating blade 132 may also be formed integrally with at least a part of the member that constitutes the holder H2. The second agitating blade 132 may also be made of a conductor other than metal instead of metal.

[0060] When the second agitating blade 132 has a rectangular plate shape, the second agitating blade 132 is fixed to the flange F2 so as to be oblique to the holder A1. This allows the second agitating blade 132 to agitate the electromagnetic waves in the cavity resonator 11 in accordance with the rotation of the electromagnetic agitator 13A. Note that the shape of the second agitating blade 132 may be other shapes instead of the rectangular plate shape. In this case, the second agitating blade 132 is fixed to the flange F2 so as to be able to agitate the electromagnetic waves in the cavity resonator 11 in accordance with the rotation of the electromagnetic agitator 13A.

[0061] In the electromagnetic stirrer 13A configured as described above, the holder H1 includes an insulator I1 that electrically insulates the first stirring blade 131 from the first wall surface W1. That is, the electromagnetic stirrer 13A is provided with the insulator I1. The insulator I1 is, for example, a part of the coupling C1, as shown in FIG. 3.

[0062] FIG. 3 is a diagram showing an example of the configuration of the coupling C1.

[0063] The coupling C1 is made up of, for example, a first member C11, an insulator I1, and a second member C12.

[0064] The first member C11 is, for example, a metal member having a recess that fits with the protrusion of the insulator I1, and is fixed to the rotating shaft A0 of the motor M with a fastener such as a screw. In FIG. 3, the rotating shaft A0 of the motor M and the fastener are omitted for simplicity. The shapes of the protrusion of the insulator I1 and the recess of the first member C11 may be any shape as long as the insulator I1 can be rotated in response to the rotation of the first member C11 when the protrusion and the recess are fitted together. In the example shown in FIG. 3, the first member C11 is in contact with the first wall surface W1. However, the first member C11 may be configured to be spaced apart from the first wall surface W1. The first member C11 may be made of a conductive material other than metal, instead of metal.

[0065] The insulator I1 is, for example, an insulator member having a convex portion that fits into a concave portion of the first member C11 and a concave portion that fits into a convex portion of the second member C12, and is a member that rotates in response to the rotation of the first member C11. The insulator I1 is, for example, a resin, but is not limited to a resin. The convex portion of the second member C12 and the concave portion of the insulator I1 may have any shape as long as the shape allows the second member C12 to rotate in response to the rotation of the insulator I1 when the convex portion and the concave portion are fitted together.

[0066] The second member C12 is, for example, a metal member having a protrusion that fits into a recess in the insulator I1, and rotates in response to the rotation of the first member C11 and the insulator I1. The second member C12 is fixed to the portion A11 by a fastener such as a screw. In FIG. 3, the fastener is omitted for simplicity. The second member C12 may be made of a non-metallic conductor instead of metal.

[0067] In this way, by including the insulator I1 in the holder H1 as part of the coupling C1, each of the first agitating blade 131 and the second agitating blade 132 is electrically insulated from the first wall surface W1. This allows the reverberation chamber 1 to prevent the first agitating blade 131 and the second agitating blade 132 from functioning as a capacitor with respect to the first wall surface W1. As a result, the reverberation chamber 1 can prevent the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and enables highly accurate EMS testing to be performed over a wider frequency band.

[0068] As shown in FIG. 4, the insulator I1 may constitute the entire coupling C1. FIG. 4 is a diagram showing another example of the configuration of the coupling C1. In the example shown in FIG. 4, the coupling C1 is composed of two members, a first member C11 and a second member C12. In this example, each of these two members is composed of the insulator I1. Unlike FIG. 3, FIG. 4 does not omit the rotating shaft A0 of the motor M and the fastener that fixes the first member C11 to the rotating shaft A0 of the motor M. Also, FIG. 4 shows the first member C11 and the second member C12 separated from each other. However, when the electromagnetic stirrer 13A is rotated by the motor M, the first member C11 and the second member C12 are fitted together.

[0069] Even when the entire coupling C1 is made of the insulator I1, the first stirring blade 131 and the second stirring blade 132 are each electrically insulated from the first wall surface W1 in the reflective chamber 1. As a result, even in this case, the reflective chamber 1 can suppress the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and can perform highly accurate EMS testing over a wider frequency band.

[0070] Furthermore, the insulator I1 may constitute a part of the coupling C1, as shown in FIG. 5. FIG. 5 is a diagram showing yet another example of the configuration of the coupling C1. In the example shown in FIG. 5, the coupling C1 is composed of a first member C11, a second member C12, a spacer S1 disposed between the first member C11 and the second member C12, and a plurality of bushes BS1 made of an insulator. In this example, the spacer S1 and the plurality of bushes BS1 are each composed of the insulator I1. In this example, the first member C11 is composed of two flanges, a flange F31 and a flange F32. In this example, the second member C12 is composed of two flanges, a flange F33 and a flange F34.

[0071] The flange F31 is a metal flange that is fixed by fasteners such as screws to the rotation shaft A0 of the motor M. The flange F31 may be made of a conductive material other than metal instead of metal.

[0072] The flange F32 is a metal flange that is fixed to the flange F31 with fasteners such as screws. Therefore, the flange F32 rotates together with the flange F31 in response to the rotation of the flange F31. Note that the flange F32 may be made of a conductive material other than metal instead of metal.

[0073] The flange F33 is a metal flange that is fixed to the flange F32 with fasteners such as screws. Therefore, the flange F33 rotates together with the flange F32 in response to the rotation of the flange F32. Note that the flange F33 may be made of a conductive material other than metal instead of metal.

[0074] An insulating spacer S1 is disposed between the flanges F32 and F33. The flanges F32 and F33 are formed with a plurality of openings through which fasteners, such as screws, for fastening the flanges F32 and F33 to each other are inserted. An insulating flange bushing, called a bushing BS1, is inserted into each of the openings in the flange F33 to fill the gap between the fastener and the flange F33. The flange bushing BS1 also fills the gap between the fastener and the flange F33 on the outside of the opening through which the fastener is inserted. Therefore, even when the flanges F32 and F33 are fastened together by the fastener, the fastener does not come into contact with the flange F33. In other words, even in this case, the fastener is electrically insulated from the flange F33.

[0075] The flange F14 is a metal flange fixed to the flange F13 with fasteners such as screws. Therefore, the flange F14 rotates together with the flange F13 in response to the rotation of the flange F13. The flange F14 is also fixed to the part A11 with fasteners such as screws. Note that the flange F14 may be made of a conductive material other than metal instead of metal.

[0076] 5, the first member C11 and the second member C12 are electrically insulated by the spacer S1 and the multiple bushings BS1. As a result, even in this case, the first stirring blade 131 and the second stirring blade 132 are each electrically insulated from the first wall surface W1. Therefore, even in this case, the reflection chamber 1 can suppress the occurrence of resonance phenomena in the electric field irradiated from the antenna 126 to the test piece at a frequency lower than the lowest-order resonance frequency, and can perform highly accurate EMS testing over a wider frequency band.

[0077] Furthermore, in the electromagnetic stirrer 13A, the holder H3 includes an insulator I2 that electrically insulates the first stirring blade 131 and the second stirring blade 132. That is, the electromagnetic stirrer 13A is provided with the insulator I2. The insulator I2 is, for example, a part or all of the coupling C2. The configuration of the coupling C2, which is partly or entirely constituted by the insulator I2, is similar to the configuration of the coupling C1 described in FIGS. 3 to 5, except that the coupling C2 is connected to the holder A131 and the holder A132, rather than the rotating shaft A0 and the part A11 of the motor M. Therefore, a detailed description of the configuration of the coupling C2 will be omitted.

[0078] Since the electromagnetic stirrer 13A is provided with the insulator I2, the first stirring blade 131 and the second stirring blade 132 are each electrically insulated from the second wall surface W2. This makes it possible for the reverberation chamber 1 to prevent the first stirring blade 131 and the second stirring blade 132 from functioning as a capacitor between the second wall surface W2 and each of them. As a result, the reverberation chamber 1 can prevent the occurrence of a resonance phenomenon in the electric field of a frequency lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and enables highly accurate EMS testing to be performed over a wider frequency band.

[0079] In addition, in the electromagnetic stirrer 13A, the holder H2 includes an insulator I3 that electrically insulates the second wall surface W2 from the second stirring blade 132. That is, the electromagnetic stirrer 13A is provided with the insulator I3. The insulator I3 is, for example, a part of the bearing B1 as shown in FIG.

[0080] Fig. 6 is a diagram showing an example of the configuration of the bearing B1. In Fig. 6, the second wall surface W2 is omitted for the sake of simplicity.

[0081] The bearing B1 includes a housing washer B11, a shaft washer B12, a plurality of metal balls (not shown) sandwiched between the housing washer B11 and the shaft washer B12, and a bearing fixing base B13 that fixes the shaft washer B12 to the second wall surface W2. The bearing fixing base B13 is fixed to the second wall surface W2 with fixing devices such as screws.

[0082] In the example shown in FIG. 6, the housing washer B11 is made of an insulator I3. This electrically insulates the first and second agitating blades 131 and 132 from the second wall W2. This prevents the first and second agitating blades 131 and 132 from functioning as capacitors with respect to the second wall W2. As a result, the reverberation chamber 1 can suppress the occurrence of resonance in the electric field irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band. In this example, some or all of the shaft washer B12, the multiple metal balls, and the bearing support base B13 may be made of metal, a non-metallic conductor, or an insulator.

[0083] As shown in FIG. 7, the insulator I3 may be a ceramic coating covering the surface of the housing washer B11. FIG. 7 illustrates another example of the configuration of the bearing B1. For simplicity, the second wall W2 is omitted from FIG. 7. In FIG. 7, the insulator I3 covering the surface of the housing washer B11 is indicated by hatching. Even when the surface of the housing washer B11 is covered with the insulator I3, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the second wall W2. In other words, even in this case, the reflective chamber 1 can prevent the first stirring blade 131 and the second stirring blade 132 from functioning as a capacitor with the second wall W2. As a result, the reflective chamber 1 can suppress the occurrence of resonance in the electric field irradiated from the antenna 126 to the test specimen at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band. In the example shown in Figure 7, some or all of the shaft washer B12, the multiple metal balls, and the bearing fixing base B13 may be made of metal, a conductor other than metal, or an insulator.

[0084] Furthermore, the insulator I3 may be a bearing support base B13, as shown in FIG. 8. FIG. 8 illustrates another example of the configuration of the bearing B1. For simplicity, the shaft washer B12 and the second wall W2 are omitted from FIG. 8. Even when the bearing support base B13 is the insulator I3, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the second wall W2. That is, in this case, the reverberation chamber 1 can prevent the first stirring blade 131 and the second stirring blade 132 from functioning as a capacitor with the second wall W2. As a result, the reverberation chamber 1 can prevent the occurrence of resonance in the electric field irradiated from the antenna 126 to the test specimen at a frequency lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band. In the example shown in Figure 8, some or all of the housing washer B11, shaft washer B12, and multiple metal balls may be made of metal, a conductor other than metal, or an insulator.

[0085] Furthermore, in the electromagnetic stirrer 13A, the holder H1 includes an insulator I4 that electrically insulates the first stirring blade 131 from the holder H1. That is, the electromagnetic stirrer 13A is equipped with the insulator I4. Here, as shown in FIG. 9, the first stirring blade 131 has an opening that separates the first stirring blade 131 from the holder A1, which is formed as a gap SP. That is, in this case, the holder A1 is inserted through this opening and does not come into direct contact with the first stirring blade 131. FIG. 9 is a diagram showing an example of the gap SP formed in the first stirring blade 131.

[0086] The insulator I4, for example, constitutes multiple bushings BS2 made of an insulator, as shown in FIG. 10. FIG. 10 is a diagram showing an example of the state of the first agitating blade 131 fixed to the flange F1. The first agitating blade 131 has multiple openings through which fasteners SC, such as screws, that fasten the first agitating blade 131 to the flange F1 are inserted. In each of these multiple openings, a flange bushing made of an insulator is inserted as a bushing BS2 to fill the gap between the fastener SC and the flange F1 within the opening. Furthermore, the flange portion of the flange bushing of the flange bushing BS2 fills the gap between the first agitating blade 131 and the flange F1 and the gap between the fastener SC and the first agitating blade 131, even outside the opening through which the fastener SC is inserted. Therefore, even when the first agitating blade 131 and the flange F1 are fixed by the fastener SC, the fastener SC does not come into contact with the first agitating blade 131. In other words, even in this case, the fixing device SC is electrically insulated from the first agitating blade 131. Furthermore, even when the first agitating blade 131 and the flange F1 are fixed by the fixing device SC, the flange F1 does not come into contact with the first agitating blade 131. In other words, even in this case, the flange F1 is electrically insulated from the first agitating blade 131. That is, since the electromagnetic agitator 13A is provided with the insulator I4, the first agitating blade 131 is electrically insulated from the holder H1. Therefore, in the example shown in FIG. 10, the first agitating blade 131 is electrically insulated from the holder H1.

[0087] When the first agitating blade 131 is electrically insulated from the holder H1, the reverberation chamber 1 can prevent the spaces between the first agitating blade 131 and the first wall surface W1, between the first agitating blade 131 and the second wall surface W2, and between the first agitating blade 131 and the second agitating blade 132 from all functioning as capacitors. As a result, the reverberation chamber 1 can prevent the occurrence of resonance phenomena in electric fields at frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, making it possible to perform highly accurate EMS testing over a wider frequency band.

[0088] As shown in FIG. 11, the insulator I4 may constitute both the multiple fasteners SC that secure the first agitating blade 131 to the flange F1 and the spacer S2 disposed between the first agitating blade 131 and the flange F1. FIG. 11 illustrates another example of the first agitating blade 131 secured to the flange F1. Even when the fasteners SC and the spacer S2 are formed of the insulator I4, the first agitating blade 131 is electrically insulated from the holder H1. Therefore, even in this case, the reverberation chamber 1 can prevent the first agitating blade 131 and the first wall surface W1, the first agitating blade 131 and the second wall surface W2, and the first agitating blade 131 and the second agitating blade 132 from functioning as a capacitor. As a result, the reverberation chamber 1 can prevent the occurrence of resonance phenomena in the electric field irradiated from the antenna 126 to the test specimen at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band.

[0089] 12, the insulator I4 may be configured as a spacer S2, a bushing BS3 that fills the gap between the metal fixture SC and the first agitating blade 131 within the opening through which each of the metal fixtures SC passes, and a spacer S3 (for example, a spacer that is disposed between the first agitating blade 131 and the fixture SC outside the opening) that is disposed between the first agitating blade 131 and the fixture SC. FIG. 12 shows yet another example of the first agitating blade 131 fixed to the flange F1. In this case, the first agitating blade 131 is also electrically insulated from the holder H1. Therefore, even in this case, the reflector chamber 1 can prevent the first agitating blade 131 and the first wall surface W1, the first agitating blade 131 and the second wall surface W2, and the first agitating blade 131 and the second agitating blade 132 from functioning as a capacitor. As a result, the reverberation chamber 1 can suppress the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and can perform highly accurate EMS testing over a wider frequency band. Note that some or all of the multiple fixtures SC may be made of a conductor other than metal.

[0090] Furthermore, in the electromagnetic stirrer 13A, the holder H2 includes an insulator I5 that electrically insulates the second agitating blade 132 from the holder H2. That is, the electromagnetic stirrer 13A is equipped with the insulator I5. Here, the second agitating blade 132 has an opening that separates the second agitating blade 132 from the holder A132, forming a gap SP2. That is, in this case, the holder A1 is inserted through this opening and does not come into direct contact with the second agitating blade 132. The configuration of the gap SP2 formed in the second agitating blade 132 is the same as the gap SP formed in the first agitating blade 131 shown in FIG. 9. Therefore, a detailed description of the configuration of the gap SP2 will be omitted. Furthermore, the configuration of the insulator I5 that electrically insulates the second agitating blade 132 from the holder H2 is the same as the configuration of the insulator I4 that electrically insulates the first agitating blade 131 from the holder H1. Therefore, a detailed description of the configuration of the insulator I5 will be omitted. When the electromagnetic stirrer 13A is provided with the insulator I5, the reflective chamber 1 can prevent the areas between the second stirring blade 132 and the first wall surface W1, between the second stirring blade 132 and the second wall surface W2, and between the first stirring blade 131 and the second stirring blade 132 from functioning as capacitors. As a result, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields at frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, making it possible to perform highly accurate EMS testing over a wider frequency band.

[0091] As described above, by providing the insulators I1 to I5 to the electromagnetic agitator 13A, the reflective chamber 1 can prevent the first agitating blade 131 and the first wall surface W1, the first agitating blade 131 and the second wall surface W2, and the first agitating blade 131 and the second agitating blade 132 from functioning as a capacitor. As a result, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, thereby enabling highly accurate EMS testing over a wider frequency band. Note that the reflective chamber 1 may be configured without some of the insulators I1 to I5. In this case, the reflective chamber 1 can prevent at least some of the spaces between the first agitating blade 131 and the first wall surface W1, the first agitating blade 131 and the second wall surface W2, and the first agitating blade 131 and the second agitating blade 132 from functioning as a capacitor. In this case, too, the reflection chamber 1 can suppress the occurrence of resonance phenomena in the electric field irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, allowing for highly accurate EMS testing to be performed over a wider frequency band.

[0092] 13 is a diagram illustrating the electric field strength inside the reflecting box 1 when a conventional electromagnetic stirrer is provided in the reflecting box 1 instead of the electromagnetic stirrer 13A. For ease of explanation, the reflecting box 1 provided with the conventional electromagnetic stirrer in place of the electromagnetic stirrer 13A will be referred to as reflecting box 1X below. Note that in FIG. 13, as an example, a case will be described in which the conventional electromagnetic stirrer is provided in the reflecting box 1X so as to rotate in a direction perpendicular to the direction of gravity, i.e., around a rotation axis parallel to the horizontal direction.

[0093] Graph GR1 shown in Figure 13 is a spectrum showing the variation in electric field strength for each frequency within the reverberation box 1X. The vertical axis of graph GR1 indicates the standard deviation of the electric field strength as a value indicating the variation in the electric field strength within the reverberation box 1X. Meanwhile, the horizontal axis of graph GR1 indicates the frequency of the electric field within the reverberation box 1X. Frequency FQ1 shown in graph GR1 is an example of the lowest-order resonance frequency. Graph GR1 shows that the variation in electric field strength within the reverberation box 1X increases at 10.5 MHz, which is a frequency lower than frequency FQ1. The cause of this increase in the variation in electric field strength is the LC resonant circuit mentioned above.

[0094] The distribution diagram MP1 in Figure 13 clearly shows the large variation in the 10.5 MHz electric field strength within the reverberation chamber 1X. The distribution diagram MP1 shows an example of the distribution of the electric field strength at a frequency of 10.5 MHz within the reverberation chamber 1X. More specifically, the distribution diagram MP1 is a contour map showing the electric field strength at each position within the reverberation chamber 1X when viewed in a direction parallel to the rotation axis of the conventional electromagnetic stirrer. Therefore, the distribution diagram MP1 includes a figure X1 indicating the position of the conventional electromagnetic stirrer and a figure X2 indicating the position of the antenna 126. The distribution diagram MP1 shows that the electric field strength within the reverberation chamber 1X is stronger the closer it is to the figure X1 representing the conventional electromagnetic stirrer. In other words, the distribution diagram MP1 shows that the electric field strength within the reverberation chamber 1X is uneven. This is one piece of evidence that the conventional electromagnetic stirrer functions as an LC resonant circuit.

[0095] On the other hand, Fig. 14 is a diagram for explaining the electric field intensity inside the reflective box 1. Note that Fig. 14 illustrates, as an example, a case where the electromagnetic stirrer 13A is provided in the reflective box 1 so as to rotate in a direction perpendicular to the direction of gravity, i.e., around a rotation axis parallel to the horizontal direction.

[0096] Graph GR2 shown in FIG. 14 is a spectrum showing the variation in electric field strength for each frequency inside the reverberation chamber 1. The vertical axis of graph GR2 indicates the standard deviation of the electric field strength as a value indicating the variation in the electric field strength inside the reverberation chamber 1. On the other hand, the horizontal axis of graph GR2 indicates the frequency of the electric field inside the reverberation chamber 1. Graph GR2 shows that an increase in the variation in the electric field strength inside the reverberation chamber 1 does not occur at frequencies lower than frequency FQ1. This reflects the fact that, inside the reverberation chamber 1, the combination of electromagnetic stirrer 13A and cavity resonator 11 and electromagnetic stirrer 13A are each prevented from functioning as a capacitor.

[0097] The distribution diagram MP2 shown in FIG. 14 clearly shows that the electric field strength at 10.5 MHz within the reverberation chamber 1 does not vary significantly. The distribution diagram MP2 shows an example of the distribution of the electric field strength at a frequency of 10.5 MHz within the reverberation chamber 1. More specifically, the distribution diagram MP2 is a contour map showing the electric field strength at each position within the reverberation chamber 1 when viewed in a direction parallel to the rotation axis of the electromagnetic stirrer 13A. For this reason, the distribution diagram MP2 includes a figure X3 indicating the position of the electromagnetic stirrer 13A and a figure X2 indicating the position of the antenna 126. The distribution diagram MP2 shows that the electric field strength within the reverberation chamber 1 is approximately uniform around the figure X2 indicating the antenna 126. In other words, the distribution diagram MP2 shows that the distribution of the electric field strength within the reverberation chamber 1 is approximately uniform.

[0098] As described above, the reflective chamber 1 can prevent at least one of the following from functioning as a capacitor: between the first agitating blade 131 and the first wall surface W1; between the first agitating blade 131 and the second wall surface W2; between the second agitating blade 132 and the first wall surface W1; between the second agitating blade 132 and the second wall surface W2; and between the first agitating blade 131 and the second agitating blade 132. As a result, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test specimen, making it possible to perform highly accurate EMS testing over a wider frequency band.

[0099] <Electromagnetic stirrer configuration example 2> A second configuration example of the electromagnetic stirrer 13 will be described below with reference to Fig. 15. Fig. 15 is a diagram showing a second configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in Fig. 15 will be referred to as electromagnetic stirrer 13B in the following description. The arrows shown in Fig. 15 indicate the up and down directions in Fig. 15. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0100] The electromagnetic stirrer 13B shown in FIG. 15 is a modified version of the electromagnetic stirrer 13A. The electromagnetic stirrer 13B does not include the coupling C2 including the insulator I2, and the portion A13 is configured as a single member. The bearing B1 in the electromagnetic stirrer 13B is a metal thrust bearing that does not include the insulator I3. However, like the electromagnetic stirrer 13A, the electromagnetic stirrer 13B includes the insulators I1, I4, and I5. In the example shown in FIG. 15, at least a portion of the coupling C1 is configured with the insulator I1. Furthermore, in this example, the holder H1 of the electromagnetic stirrer 13B includes the insulator I4 that electrically insulates the first stirring blade 131 from the holder H1. Furthermore, in this example, the holder H2 of the electromagnetic stirrer 13B includes the insulator I5 that electrically insulates the second stirring blade 132 from the holder H2. In this case, in the reverberation chamber 1, the first agitating blade 131 and the second agitating blade 132 are electrically insulated from the first wall surface W1, the first agitating blade 131 and the second agitating blade 132 are electrically insulated from the second wall surface W2, and the first agitating blade 131 and the second agitating blade 132 are electrically insulated from each other. As a result, even in this case, the reverberation chamber 1 can prevent the following from functioning as a capacitor: the first agitating blade 131 and the first wall surface W1; the first agitating blade 131 and the second wall surface W2; the second agitating blade 132 and the first wall surface W1; the second agitating blade 132 and the second wall surface W2; and the first agitating blade 131 and the second agitating blade 132. Therefore, the reverberation chamber 1 can prevent the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test specimen, enabling highly accurate EMS testing to be performed over a wider frequency band. In the electromagnetic stirrer 13B, at least a portion of the bearing B1 may be formed of the insulator I3. The electromagnetic stirrer 13B may also be configured to include some of the insulators I1, I4, and I5. The electromagnetic stirrer 13B may also be configured to include either or both of the insulators I2 and I3 instead of some or all of the insulators I1, I4, and I5.In these cases, the reflection box 1 can prevent some of the spaces between the first stirring blade 131 and the first wall surface W1, between the first stirring blade 131 and the second wall surface W2, between the second stirring blade 132 and the first wall surface W1, between the second stirring blade 132 and the second wall surface W2, and between the first stirring blade 131 and the second stirring blade 132 from functioning as a capacitor.

[0101] <Configuration example 3 of electromagnetic stirrer> Hereinafter, a third configuration example of the electromagnetic stirrer 13 will be described with reference to Fig. 16. Fig. 16 is a diagram showing a third configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in Fig. 16 will be referred to as an electromagnetic stirrer 13C in the following description. The arrows shown in Fig. 16 indicate the up and down directions in Fig. 16. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0102] The electromagnetic stirrer 13C shown in FIG. 16 is a modified example of the electromagnetic stirrer 13A. The electromagnetic stirrer 13C does not include the insulators I4 and I5. However, like the electromagnetic stirrer 13A, the electromagnetic stirrer 13C includes the insulators I1 to I3. In the example shown in FIG. 16, at least a portion of the coupling C1 is made of the insulator I1. In addition, in this example, at least a portion of the coupling C2 is made of the insulator I2. In addition, in this example, at least a portion of the bearing B1 is made of the insulator I3. In this case, in the reflector chamber 1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the first wall surface W1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the second wall surface W2, and the first stirring blade 131 and the second stirring blade 132 are electrically insulated from each other. As a result, even in this case, the reflective chamber 1 can prevent the following from functioning as a capacitor: between the first agitating blade 131 and the first wall surface W1; between the first agitating blade 131 and the second wall surface W2; between the second agitating blade 132 and the first wall surface W1; between the second agitating blade 132 and the second wall surface W2; and between the first agitating blade 131 and the second agitating blade 132. Therefore, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band. The electromagnetic agitator 13B may be configured to include either an insulator I4 or an insulator I5 in addition to the insulators I1 to I3. The electromagnetic agitator 13B may also be configured to include either or both of the insulators I4 and I5 instead of some or all of the insulators I1 to I3.

[0103] <Configuration example 4 of electromagnetic stirrer> Hereinafter, a fourth configuration example of the electromagnetic stirrer 13 will be described with reference to FIG. 17. FIG. 17 is a diagram showing a fourth configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in FIG. 17 will be referred to as an electromagnetic stirrer 13D in the following description. The arrows shown in FIG. 17 indicate the up and down directions in FIG. 17. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0104] The electromagnetic stirrer 13D shown in FIG. 17 is a modified example of the electromagnetic stirrer 13A. The electromagnetic stirrer 13D does not include a motor M, but includes a linear actuator (not shown) that vibrates the electromagnetic stirrer 13D along the first direction. This linear actuator is provided, for example, inside at least one of the flanges F1 and F2. On the other hand, the electromagnetic stirrer 13D, like the electromagnetic stirrer 13A, includes insulators I1 to I5. In the example shown in FIG. 17, at least a portion of the coupling C1 is made of the insulator I1. Also, in this example, at least a portion of the coupling C2 is made of the insulator I2. Also, in this example, at least a portion of the bearing B1 is made of the insulator I3. Also, in this example, the holder H1 of the electromagnetic stirrer 13D includes an insulator I4 that electrically insulates the first stirring blade 131 from the holder H1. Also, in this example, the holder H2 of the electromagnetic stirrer 13D includes an insulator I5 that electrically insulates the second stirring blade 132 from the holder H2. Therefore, in this case as well, in the reflecting chamber 1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the first wall surface W1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the second wall surface W2, and the first stirring blade 131 and the second stirring blade 132 are electrically insulated from each other. As a result, even in this case, the reflecting chamber 1 can prevent the first stirring blade 131 and the first wall surface W1, the first stirring blade 131 and the second wall surface W2, the second stirring blade 132 and the first wall surface W1, the second stirring blade 132 and the second wall surface W2, and the first stirring blade 131 and the second stirring blade 132 from all functioning as capacitors. Therefore, the reflection chamber 1 can suppress the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and can perform high-precision EMS tests over a wider frequency band with good accuracy. Note that the electromagnetic stirrer 13D may be configured to include some of the insulators I1 to I5.In this case, the reflection box 1 can prevent some of the spaces between the first stirring blade 131 and the first wall surface W1, between the first stirring blade 131 and the second wall surface W2, between the second stirring blade 132 and the first wall surface W1, between the second stirring blade 132 and the second wall surface W2, and between the first stirring blade 131 and the second stirring blade 132 from functioning as a capacitor.

[0105] <Electromagnetic stirrer configuration example 5> Hereinafter, a fifth configuration example of the electromagnetic stirrer 13 will be described with reference to FIG. 18. FIG. 18 is a diagram showing a fifth configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in FIG. 18 will be referred to as an electromagnetic stirrer 13E in the following description. The arrows shown in FIG. 18 indicate the up and down directions in FIG. 18. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0106] Electromagnetic stirrer 13E shown in Fig. 18 is a modified example of electromagnetic stirrer 13A. Holder A1 of electromagnetic stirrer 13E does not have portion A12 or holder A132 of portion A13, but has portion A11 and holder A131 of portion A13. Electromagnetic stirrer 13E shown in Fig. 18 does not have coupling C2, second stirring blade 132, flange F2, or bearing B1, but has first stirring blade 131. Holder A1 may also not have holder A131.

[0107] Therefore, the electromagnetic stirrer 13E is connected to the first wall surface W1 but not to the second wall surface W2. The electromagnetic stirrer 13E includes an insulator I1 and an insulator I4, similar to the electromagnetic stirrer 13A. In the example shown in FIG. 18, at least a portion of the coupling C1 is made of the insulator I1. In this example, the holder H1 of the electromagnetic stirrer 13D includes an insulator I4 that electrically insulates the first stirring blade 131 from the holder H1. In this case, the first stirring blade 131 is electrically insulated from the first wall surface W1 in the reflective chamber 1. Naturally, the first stirring blade 131 is also electrically insulated from the second wall surface W2 in the reflective chamber 1. As a result, even in this case, the reflective chamber 1 can prevent the first stirring blade 131 and the first wall surface W1 and the first stirring blade 131 and the second wall surface W2 from functioning as capacitors. Therefore, the reflection chamber 1 can suppress the occurrence of resonance phenomena in electric fields of frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, and can perform high-precision EMS tests over a wider frequency band with good accuracy. Note that the electromagnetic stirrer 13E may be configured without either the insulator I1 or the insulator I4.

[0108] <Configuration example 6 of electromagnetic stirrer> Hereinafter, a sixth configuration example of the electromagnetic stirrer 13 will be described with reference to Fig. 19. Fig. 19 is a diagram showing a sixth configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in Fig. 19 will be referred to as an electromagnetic stirrer 13F in the following description. The arrows shown in Fig. 19 indicate the up and down directions in Fig. 19. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0109] The electromagnetic stirrer 13F shown in FIG. 19 is a modified example of the electromagnetic stirrer 13A. The electromagnetic stirrer 13F does not include the coupling C2 including the insulator I2, and the portion A13 is configured as a single member. In the electromagnetic stirrer 13F, the holder A1, flange F1, and flange F2 are each made of an insulator. In other words, the electromagnetic stirrer 13F includes the holder A1 made of an insulator, the flange F1 made of an insulator, and the flange F2 made of an insulator as the insulators I4 and I5, respectively. In addition, the electromagnetic stirrer 13F includes the insulators I1 and I3. In this case, too, in the reflector chamber 1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the first wall surface W1, the first stirring blade 131 and the second stirring blade 132 are electrically insulated from the second wall surface W2, and the first stirring blade 131 and the second stirring blade 132 are electrically insulated from each other. As a result, even in this case, the reverberation chamber 1 can prevent the following from functioning as a capacitor: between the first agitating blade 131 and the first wall surface W1; between the first agitating blade 131 and the second wall surface W2; between the second agitating blade 132 and the first wall surface W1; between the second agitating blade 132 and the second wall surface W2; and between the first agitating blade 131 and the second agitating blade 132. Therefore, the reverberation chamber 1 can prevent the occurrence of resonance phenomena in electric fields irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band. The electromagnetic agitator 13F may be configured with a coupling C2. In addition, in the electromagnetic agitator 13F, a portion of the holder A1, flange F1, and flange F2 may be made of metal or a non-metallic conductor.

[0110] <Configuration example 7 of electromagnetic stirrer> Hereinafter, a seventh configuration example of the electromagnetic stirrer 13 will be described with reference to FIG. 20. FIG. 20 is a diagram showing the seventh configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in FIG. 20 will be referred to as an electromagnetic stirrer 13G in the following description. The arrows shown in FIG. 20 indicate the up and down directions in FIG. 20. The up direction indicated by this arrow indicates the direction opposite to the direction of gravity. The down direction indicated by this arrow indicates the direction of gravity.

[0111] The electromagnetic stirrer 13G shown in FIG. 20 is a modified example of the electromagnetic stirrer 13E. In the example shown in FIG. 20, the first wall surface W1 is one of the side wall surfaces of the cavity resonator 11, instead of the ceiling surface of the cavity resonator 11. Therefore, the aforementioned first direction is a direction intersecting with the side wall surface used as the first wall surface W1 among the walls of the cavity resonator 11. In the example shown in FIG. 20, the first direction is a direction perpendicular to the first wall surface W1, i.e., a direction perpendicular to the direction of gravity. Therefore, the holder A1 of the electromagnetic stirrer 13G is provided on the first wall surface W1 so that the rotation axis of the electromagnetic stirrer 13G is perpendicular to the direction of gravity. For simplification, the motor M and the flange F1 are omitted from FIG. 20.

[0112] 20, the weight of the first stirring blade 131 applies a moment that tends to rotate the part A11 in the direction of gravity around the vicinity of the coupling C1. Therefore, in this example, the reflector box 1 further includes a support SB that supports the part A11 of the holder A1. Note that the support SB may be configured to support the holder A131 of the holder A1 instead of the part A11 of the holder A1.

[0113] The support SB includes a bearing B2, a first support SB1 that supports the bearing B2, a second support SB2 that supports the first support SB1, a spacer S4 that is arranged between the first support SB1 and the second support SB2, and a plurality of fasteners SC2 that fasten the first support SB1 and the second support SB2.

[0114] The bearing B2 is a metal bearing through which the holder A1 is inserted and which supports the rotating holder A1. Note that the bearing B2 may be made of a conductive material other than metal instead of metal.

[0115] The first support body SB1 is a metal member that supports the bearing B2. Note that the first support body SB1 may be made of a non-metallic conductive material instead of metal.

[0116] The second support body SB2 is a metal member that supports the first support body SB1. Note that the second support body SB2 may be made of a conductor other than metal instead of metal.

[0117] The spacer S4 is an insulating spacer and is made of an insulator I6.

[0118] The fixing tool SC2 is, for example, a screw made of an insulating material, and is made of an insulating material I6.

[0119] Thus, the reflective chamber 1 includes the insulator I1 included in the coupling C1, the insulator I4 electrically insulating the first agitating blade 131 from the holder H1, and the insulator I6. As shown in FIG. 20, the insulator I6 electrically insulates the first support SB1 from the second support SB2. In other words, the insulator I6 electrically insulates the electromagnetic agitator 13A from the floor of the reflective chamber 1 to which the second support SB2 is fixed. Therefore, even when the reflective chamber 1 includes the support SB supporting the holder A1 of the electromagnetic agitator 13A, the insulator I6 prevents the first agitating blade 131 from functioning as a capacitor with the first wall surface W1. As a result, even in this case, the reflective chamber 1 can suppress the occurrence of resonance in the electric field irradiated from the antenna 126 to the test piece at a frequency lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band.

[0120] As shown in FIG. 21, the support SB may be provided with a bearing B3 instead of the bearing B2, eliminating the spacer S4 and integrating the first support SB1 and the second support SB2. FIG. 21 illustrates a first variation of the support SB configuration shown in FIG. 20. The bearing B3 is a bearing partially or entirely made of the insulator I6. For example, the entire bearing B3 may be made of the insulator I6, or the holder may be made of the insulator I6, or other portions capable of electrically insulating the holder A1 from the support SB may be made of the insulator I6. In this case, the reflective chamber 1 can also prevent the first stirring blade 131 and the first wall surface W1 from functioning as a capacitor. As a result, even in this case, the reflective chamber 1 can suppress the occurrence of resonance in the electric field irradiated from the antenna 126 to the test specimen at a frequency lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band.

[0121] Alternatively, as shown in FIG. 22, the support SB may include a spacer S5, but not the spacer S4, and the first support SB1 and the second support SB2 may be integrally configured. FIG. 22 illustrates a second variation of the support SB configuration shown in FIG. 20. The spacer S5 is made of an insulator I6 and is disposed between the second support SB2 and the floor of the reflective chamber 1. The second support SB2 is fixed to the spacer S5 with fasteners such as screws. The spacer S5 is fixed to the floor with fasteners such as screws. In this case, the reflective chamber 1 can also prevent the first stirring blade 131 and the first wall surface W1 from functioning as a capacitor. As a result, even in this case, the reflective chamber 1 can suppress the occurrence of resonance in the electric field irradiated from the antenna 126 to the test specimen at a frequency lower than the lowest-order resonance frequency, enabling highly accurate EMS testing over a wider frequency band.

[0122] 23, the support SB may not include the spacer S4, and the first support SB1 and the second support SB2 may each be made of an insulator I6, with the first support SB1 and the second support SB2 being integrally configured. FIG. 23 is a diagram showing a third modified example of the configuration of the support SB shown in FIG. 20. In this case, the reflective chamber 1 can also prevent the first stirring blade 131 and the first wall surface W1 from functioning as a capacitor. As a result, even in this case, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, allowing for accurate EMS testing over a wider frequency band.

[0123] <Configuration example 8 of electromagnetic stirrer> Hereinafter, an eighth configuration example of the electromagnetic stirrer 13 will be described with reference to Fig. 24. Fig. 24 is a diagram showing an eighth configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in Fig. 24 will be referred to as electromagnetic stirrer 13H in the following description. The arrows shown in Fig. 24 indicate the up and down directions in Fig. 24. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0124] The electromagnetic stirrer 13H shown in Fig. 24 includes two of the electromagnetic stirrers 13G shown in Fig. 20. For ease of explanation, one of the two electromagnetic stirrers 13G will be referred to as electromagnetic stirrer 13G1, and the other of the two electromagnetic stirrers 13G will be referred to as electromagnetic stirrer 13G2.

[0125] In the electromagnetic stirrer 13H shown in FIG. 24, the holder A1 of the electromagnetic stirrer 13G1 is attached to the first wall surface W1 via a coupling C1. Meanwhile, in the electromagnetic stirrer 13H, the holder A1 of the electromagnetic stirrer 13G2 is attached to the second wall surface W2 via a coupling C1. Here, in the example shown in FIG. 24, the second wall surface W2 refers to the side wall surface facing the first wall surface W1 among the walls within the reflector box 1. In the example shown in FIG. 24, the first stirring blade 131 of the electromagnetic stirrer 13G1 can be regarded as the first stirring blade 131 of the electromagnetic stirrer 13H, and the first stirring blade 131 of the electromagnetic stirrer 13G2 can be regarded as the second stirring blade 132 of the electromagnetic stirrer 13H. When viewed in this way, the reflective chamber 1 can prevent the following from functioning as a capacitor: between the first stirring blade 131 of the electromagnetic stirrer 13H and the first wall surface W1; between the first stirring blade 131 of the electromagnetic stirrer 13H and the second wall surface W2; between the second stirring blade 132 of the electromagnetic stirrer 13H and the first wall surface W1; between the second stirring blade 132 of the electromagnetic stirrer 13H and the second wall surface W2; and between the first stirring blade 131 of the electromagnetic stirrer 13H and the second stirring blade 132 of the electromagnetic stirrer 13H. As a result, the reflective chamber 1 can prevent the occurrence of resonance phenomena in the electric field irradiated from the antenna 126 to the test piece at frequencies lower than the lowest-order resonance frequency, enabling highly accurate EMS testing to be performed over a wider frequency band.

[0126] <Configuration example 9 of electromagnetic stirrer> A ninth configuration example of the electromagnetic stirrer 13 will be described below with reference to Fig. 25. Fig. 25 is a diagram showing a ninth configuration example of the electromagnetic stirrer 13. For ease of explanation, the electromagnetic stirrer 13 shown in Fig. 25 will be referred to as electromagnetic stirrer 13I in the following description. The arrows shown in Fig. 25 indicate the up and down directions in Fig. 25. The upward direction indicated by this arrow indicates the direction opposite to the direction of gravity. The downward direction indicated by this arrow indicates the direction of gravity.

[0127] The electromagnetic stirrer 13I shown in FIG. 25 includes a rectangular, flat holder A1. In the example shown in FIG. 25, the holder A1 is slidably placed on the first wall W1, which corresponds to the floor of the cavity resonator 11. The first wall W1 is the direction opposite to the direction of gravity, and the holder A1 extends in the first direction. A triangularly wavy metal plate is provided on the surface of the holder A1 as a first stirring blade 131. Each of the holder A1 and the first stirring blade 131 has an opening that penetrates from the first stirring blade 131 toward the holder A1. A portion of a support SB3 that supports the holder A1 so as not to tip over is inserted into this opening. The support SB3 is composed of, for example, a first support SB31 and a second support SB32. The first support SB31 is a member fixed to the first wall W1 and extending in the first direction. The second support SB2 is connected to the first support SB1, extends in a second direction perpendicular to the first direction, and is fixed to one of the walls of the cavity resonator 11 on the second direction side. In the reflective box 1, the holder A1 vibrates back and forth in the second direction along the second support SB2. This vibration is achieved by a linear actuator or the like (not shown). The support SB3 is formed of an insulator I7 that insulates the holder A1 from the first wall W1. That is, the reflective box 1 is provided with the insulator I7.

[0128] When the electromagnetic stirrer 13I is configured in this manner, the holder A1 is electrically insulated from the support SB3. As a result, even in this case, the reflective chamber 1 can prevent the first agitating blade 131 and the first wall surface W1, and the first agitating blade 131 and the support SB3 from functioning as capacitors. In other words, even in this case, the reflective chamber 1 can prevent the occurrence of resonance phenomena in electric fields at frequencies lower than the lowest-order resonance frequency among the electric fields irradiated from the antenna 126 to the test piece, allowing for highly accurate EMS testing to be performed over a wider frequency band.

[0129] Among the portions of the wall surface inside the cavity resonator 11 described above, the portions where the electromagnetic stirrers 13 and the cavity resonator 11 come into contact with each other may be made of an insulating material. Furthermore, the configurations of the electromagnetic stirrers 13 described above may be combined in any manner. Furthermore, the coupling C1 described above may be a bearing. Furthermore, the coupling C2 described above may be a bearing. Furthermore, the bearing B1 described above may be a coupling.

[0130] Furthermore, materials used for insulating bushings such as bushing BS2, insulating screws (or bolts) such as fixture SC, insulating spacers such as spacer S1, insulating bases such as bearing fixing base B13, etc. include polyamide resin, polypropylene, polytetrafluoroethylene, glass fiber reinforced plastic, polyacetal, phenol resin, polyether ether ketone resin, polyphenylene sulfide, etc., as shown in Figure 26. That is, the material has a volume resistivity of at least 10 11 It is desirable that the material have an electrical resistance of at least about Ω·cm. Figure 26 is a table showing a list of materials used for insulating bushings such as bushing BS2, insulating screws (or bolts) such as fixing device SC, insulating spacers such as spacer S1, insulating bases such as bearing fixing base B13, etc.

[0131] Furthermore, materials used for bearings made entirely of insulating material, such as the bearing B1 shown in FIG. 6, include silicon nitride, zirconia, etc., as shown in FIG. 27. That is, the material has a volume resistivity of at least 10 8 It is desirable for the material to have an electrical resistance of at least about Ω·cm. Figure 27 is a table showing a list of materials that can be used for bearings made entirely of insulating materials, such as bearing B1 shown in Figure 6.

[0132] 27 also shows a table listing materials used for the insulating coating of the bearing B1 shown in FIG. 7. As shown in FIG. 27, the material used for the insulating coating of the bearing B1 shown in FIG. 7 includes alumina, etc. In other words, the material has a volume resistivity of at least 10 14 It is desirable that the material have an electrical resistance of at least about Ω·cm. Figure 28 is a table showing a list of materials used for the insulating coating of bearing B1 shown in Figure 7.

[0133] Furthermore, the materials used for the metal members described above, excluding the cavity resonator 11 and the fixture (for example, the holder A1, the first stirring blade 131, etc.), may be metal as described above, or may be a conductor other than metal. Therefore, examples of materials used for these members include aluminum, stainless steel (SUS304), and carbon fiber reinforced conductive plastics, as shown in FIG. 28. That is, the material has a conductivity of at least 10 3 It is desirable that the material has a resistance of about S / m or more. Figure 28 is a table showing a list of materials used for conductive members.

[0134] Furthermore, fixtures other than the fixtures described above that are clearly stated to be made of an insulator (for example, metallic fixtures SC) may be made of metal or a conductor other than metal. In this case, materials used for metallic fixtures or fixtures made of a conductor other than metal include nickel chrome steel, stainless steel (SUS304), etc., as shown in FIG. 29. In other words, the material has a conductivity of at least 10 4 It is desirable that the material has a resistance of about S / m or more. Figure 29 is a table showing a list of materials used for fasteners made of metal or conductive materials other than metal.

[0135] As described above, the reflecting box according to the embodiment (reflecting box 1 in the example described above) is a reflecting box equipped with an electromagnetic stirrer (electromagnetic stirrers 13A to 13I in the example described above), and the electromagnetic stirrer includes a first stirring blade (first stirring blade 131 in the example described above) and a holder (holder A1 in the example described above) that is provided on a first wall surface of the reflecting box (first wall surface W1 in the example described above) and extends in a first direction that intersects with the first wall surface (the direction of gravity, the direction perpendicular to gravity, or the direction opposite to the direction of gravity in the example described above), and that holds the first stirring blade, and the first stirring blade is electrically insulated from the first wall surface. This allows the reflecting box to perform highly accurate EMS testing over a wider frequency band.

[0136] In addition, in the reflection box, a configuration may be used in which the electromagnetic stirrer is aligned with the first stirring blade in the first direction and further includes a second stirring blade (in the example described above, second stirring blade 132) provided on the holder.

[0137] Furthermore, the reflector box may be configured such that the first stirring blade is electrically insulated from the second stirring blade.

[0138] The reverberation box is also equipped with an electromagnetic stirrer, the electromagnetic stirrer including a first stirring blade, a second stirring blade, and a holder provided on a first wall surface of the reverberation box, extending in a first direction intersecting the first wall surface, and holding the first stirring blade and the second stirring blade side by side in the first direction, the first stirring blade being electrically insulated from the second stirring blade. This allows the reverberation box to perform highly accurate EMS testing over a wider frequency band.

[0139] Furthermore, in the reflector box, a configuration may be used in which the holder has a first insulator (insulator I3 in the example described above) that electrically insulates the first stirring blade and the second stirring blade.

[0140] In addition, in the reflection box, a configuration may be used in which the holder includes a first holder (in the example described above, holder A131) that connects to the first stirring blade, a second holder (in the example described above, holder A132) that connects to the second stirring blade, and a first coupling (in the example described above, coupling C2) that connects the first holder and the second holder, and the first insulator is at least a part of the first coupling.

[0141] Furthermore, in the reflective box, a configuration may be used in which the holder has a second insulator (insulator I5 in the example described above) that electrically insulates the second stirring blade and the holder.

[0142] Furthermore, the reflective box may have a configuration in which a bush made of an insulating material (bush BS2 in the example described above) is used as at least a part of the second insulator.

[0143] In addition, in the reflection box, a first spacer (spacer S2 in the example described above) made of an insulator and placed between the second stirring blade and the holder may be used as at least a part of the second insulator, and the second stirring blade, the first spacer, and the holder may be fixed by a fixing device made of an insulator (fixing device SC in the example described above).

[0144] Furthermore, in the reflector box, a configuration may be used in which the holder has a third insulator (insulator I1 in the example described above) that electrically insulates the first stirring blade and the first wall surface.

[0145] In addition, in the reflector box, a configuration may be used in which the holder includes a third holder (in the example described above, the rotating shaft A0 of the motor M) electrically connected to the first wall surface, a fourth holder (in the example described above, part A11) connected to the first stirring blade, and a second coupling (in the example described above, coupling C1) connecting the third holder and the fourth holder, and the third insulator is at least a part of the second coupling.

[0146] Furthermore, in the reflective box, a configuration may be used in which the holder has a fourth insulator (insulator I4 in the example described above) that electrically insulates the first stirring blade and the holder.

[0147] Furthermore, the reflective box may be configured such that a bush made of an insulating material (bush BS2 in the example described above) is used as at least a part of the fourth insulator.

[0148] In addition, in the reflection box, a second spacer (spacer S2 in the example described above) made of an insulator and placed between the first stirring blade and the holder may be used as at least a part of the fourth insulator, and the first stirring blade, the second spacer, and the holder may be fixed by a fixing device made of an insulator (fixing device SC in the example described above).

[0149] In addition, in the reflective box, the holder may be configured to have a fifth insulator connecting the holder to the first wall surface (in the example described above, a coupling C1 (or a bearing in place of the coupling C1) when in contact with the first wall surface W1, a portion of the first wall surface W1 made of an insulator that contacts the holder A1, etc.).

[0150] The reflective box may also be configured such that a bearing that electrically insulates the holder from the first wall surface is used as at least a part of the fifth insulator.

[0151] In addition, the reflective box may be configured such that a third coupling (in the example described above, the coupling C1 when in contact with the first wall W1) that electrically insulates the holder from the first wall W1 is used as at least part of the fifth insulator.

[0152] Furthermore, the reflective box may have a configuration in which the holder is an insulator.

[0153] In addition, the reflective box may further include a support body (in the example described above, support body SB, support body SB3) that supports the holder, and the support body may be provided on the second wall surface of the reflective box (in the example described above, the floor surface of the reflective box 1).

[0154] The reflector box may have a configuration in which the holder is electrically insulated from the second wall surface.

[0155] Also, in the reflective box, a configuration may be used in which the support is an insulator.

[0156] The reflective box may also have a configuration having a sixth insulator (insulator I6 in the example described above) that electrically insulates the holder and the support.

[0157] Furthermore, the reflective box may be configured such that a bearing (bearing B3 in the example described above) that electrically insulates the holder and the support body is used as at least a part of the sixth insulator.

[0158] Furthermore, the reflective box may be configured such that a fixture made of an insulating material (the fixture SC2 in the example described above) is used as at least a part of the sixth insulator.

[0159] In addition, the reflective box may be configured such that at least a part of the sixth insulator is made of an insulating material and a third spacer (spacer S4 in the example described above) is arranged between the holder and the support.

[0160] Furthermore, in the reflective box, a configuration may be used in which the support includes a seventh insulator (insulator I6 in the example described above) that electrically insulates the support from the second wall surface.

[0161] In addition, in the reflective box, a fourth spacer (spacer S5 in the example described above) made of an insulator and arranged between the support body and the second wall surface may be used as at least a part of the seventh insulator, and the support body, the fourth spacer, and the second wall surface may be fixed by a fixing device made of an insulator (a fixing device that fixes spacer S5 to the floor surface of the reflective box 1 in the example described above).

[0162] In addition, the reflecting box may be configured such that the end opposite to the end connected to the first wall surface of the holder is connected to the third wall surface of the reflecting box (in the example described above, the second wall surface W2).

[0163] Furthermore, the reflector box may be configured such that the first stirring blade is electrically insulated from the third wall surface.

[0164] Furthermore, in the reflective box, a configuration may be used in which the holder has an eighth insulator (insulator I2 in the example described above) connecting between the holder and the third wall surface.

[0165] Furthermore, the reflective box may be configured such that a bearing (bearing B1 in the example described above) that electrically insulates the holder from the third wall surface is used as at least a part of the eighth insulator.

[0166] In addition, the reflective box may be configured such that a fourth coupling (in the example described above, the coupling used in place of bearing B1) that electrically insulates the holder from the third wall surface is used as at least part of the eighth insulator.

[0167] In addition, the reflective box may be configured such that a fourth coupling (in the example described above, the coupling used in place of bearing B1) that electrically insulates the holder from the third wall surface is used as at least part of the eighth insulator.

[0168] Furthermore, in the reflective box, a configuration may be used in which the holder is electrically insulated from the support.

[0169] Although an embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and may be changed, replaced, deleted, etc., without departing from the gist of the present invention. [Explanation of symbols]

[0170] 1, 1X... Reverberation chamber, 11... Cavity resonator, 12... Test equipment, 13, 13A, 13B, 13C, 13D, 13E, 13F, 13G, 13G1, 13G2, 13H, 13I... Electromagnetic stirrer, 14... Control device, 121... Signal generator, 122... Amplifier, 123... Directional coupler, 124... Stirrer controller, 125... Power meter, 126... Antenna, 131... First stirring blade, 132... Second stirring blade, A0... Rotating shaft, A1, A131, A132, H1, H2, H3... Holder, A11, A12, A13... Part, B1, B2, B3... Bearing, B11... Housing washer, B12...shaft washer, B13...bearing fixing base, BS1, BS2, BS3...bushing, C1, C2...coupling, C11...first member, C12...second member, F1, F2, F13, F14, F31, F32, F33, F34...flange, I1, I2, I3, I4, I5, I6, I7...insulator, M...motor, S1, S2, S3, S4, S5...spacer, SB, SB3...support, SB1, SB31...first support, SB2, SB32...second support, SC, SC2...fixture, TM...test specimen, W1...first wall, W2...second wall

Claims

1. A reflective box equipped with an electromagnetic stirrer, The electromagnetic stirrer is A first stirring blade; a holder provided on a first wall surface of the reflecting box, extending in a first direction intersecting the first wall surface, and holding the first stirring blade; a support body that supports the holder; Equipped with the first stirring blade has at least an insulator located in a portion of the holder between the first wall surface and the first stirring blade, and is electrically insulated from the first wall surface by the insulator; the first wall surface is a side surface of the reflective box, the support body is provided on a second wall surface, which is the bottom surface of the reflecting box, and supports the holder in a direction opposite to the direction of gravity. reflective box.

2. the electromagnetic stirrer further includes a second stirring blade arranged next to the first stirring blade in the first direction and provided on the holder; The reflective box according to claim 1.

3. The first agitating blade is electrically insulated from the second agitating blade. The reflector box according to claim 2.

4. A reflective box equipped with an electromagnetic stirrer, The electromagnetic stirrer is A first stirring blade; A second stirring blade; a holder provided on a first wall surface of the reflecting box, extending in a first direction intersecting the first wall surface, and holding the first stirring blade and the second stirring blade side by side in the first direction; a support body that supports the holder; Equipped with the stirring blade, of the first stirring blade and the second stirring blade, closer to the first wall surface has at least an insulator located in a portion of the holder between the first wall surface and the first stirring blade, and is electrically insulated from the first wall surface by the insulator; the first agitating blade is electrically insulated from the second agitating blade; the first wall surface is a side surface of the reflective box, the support body is provided on a second wall surface, which is the bottom surface of the reflecting box, and supports the holder in a direction opposite to the direction of gravity. reflective box.

5. the holder has a first insulator that electrically insulates the first stirring blade and the second stirring blade; The reflector box according to any one of claims 2 to 4.

6. the holder includes a first holder connected to the first stirring blade, a second holder connected to the second stirring blade, and a first coupling connecting the first holder and the second holder, the first insulator is at least a part of the first coupling; The reflector box according to claim 5.

7. The holder has a second insulator that electrically insulates the second stirring blade from the holder. The reflector box according to any one of claims 2 to 4.

8. A bushing made of an insulating material is used as at least a part of the second insulator. The reflector box according to claim 7.

9. a first spacer made of an insulating material is used as at least a part of the second insulator and is disposed between the second stirring blade and the holder; The second stirring blade, the first spacer, and the holder are fixed by a fixing tool made of an insulating material.

9. The reflector box according to claim 7 or 8.

10. the holder has a third insulator that electrically insulates the first stirring blade from the first wall surface; A reflector box according to any one of claims 1 to 9.

11. the holder includes a third holder electrically connected to the first wall surface, a fourth holder connected to the first stirring blade, and a second coupling connecting the third holder and the fourth holder, the third insulator is at least a part of the second coupling; The reflective box according to claim 10.

12. the holder has a fourth insulator that electrically insulates the first stirring blade from the holder; A reflective box according to any one of claims 1 to 11.

13. A bush made of an insulating material is used as at least a part of the fourth insulator. The reflective box according to claim 12.

14. a second spacer made of an insulating material is used as at least a part of the fourth insulator and is disposed between the first stirring blade and the holder; The first stirring blade, the second spacer, and the holder are fixed by an insulating fastener. The reflector box according to claim 12 or 13.

15. The holder is an insulator. A reflective box according to any one of claims 1 to 14.

16. The holder is electrically insulated from the second wall surface. A reflective box according to any one of claims 1 to 15.

17. The support is an insulator. A reflective box according to any one of claims 1 to 16.

18. a sixth insulator that electrically insulates the holder from the support; A reflective box according to any one of claims 1 to 17.

19. A bearing that electrically insulates the holder and the support body is used as at least a part of the sixth insulator.

19. The reflective box according to claim 18.

20. An insulator-made fastener is used as at least a part of the sixth insulator.

20. The reflector box according to claim 18 or 19.

21. a third spacer made of an insulator and disposed between the holder and the support body is used as at least a part of the sixth insulator; A reflective box according to any one of claims 18 to 20.

22. the support body includes a seventh insulator that electrically insulates the support body from the second wall surface. A reflective box according to any one of claims 1 to 21.

23. a fourth spacer made of an insulator and disposed between the support body and the second wall surface is used as at least a part of the seventh insulator; The support body, the fourth spacer, and the second wall surface are fixed together by an insulating fastener.

23. The reflective box according to claim 22.

24. The holder is electrically insulated from the support. A reflective box according to any one of claims 1 to 23.

25. A reflector box according to any one of claims 1 to 24, Antenna device.

Images