JP4517429B2 - Turntable device for anechoic chamber - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anechoic chamber turntable device in which a specimen is placed and rotates in an anechoic chamber.
[0002]
[Prior art]
Conventionally, anechoic chambers have been used to measure the radiated noise intensity of devices that generate noise that causes electromagnetic interference to other devices, or to test malfunctions by irradiating electronic devices with electromagnetic waves of strong electromagnetic fields. Yes. In this anechoic chamber, the entire room is covered with an electromagnetic wave shielding material to shield the room against electromagnetic waves (hereinafter referred to as electromagnetic wave shielding), and an electromagnetic wave absorber is provided on the wall surface and ceiling surface of the room. It prevents the reflection of radio waves by the ceiling surface.
[0003]
Conventionally, in an anechoic chamber, as a measurement support facility, a specimen (test object) is placed, a turntable that rotates, and an antenna mast to which an antenna is attached are used.
[0004]
Here, an example of the structure of a conventional turntable will be described with reference to FIG. In this example, the turntable 210 is provided so as to form a part of the floor 201 of the anechoic chamber. A turntable pit 202 is formed under the turntable 210. In the turntable pit 202, a driving device 211 for rotating the turntable 210 is provided.
[0005]
The outer peripheral portion of the turntable 210 and the surrounding floor portion 203 are electrically connected by an electrical connection member 204 such as an earth roller.
[0006]
A specimen 213 is placed on the turntable 210 via a table 212, for example.
[0007]
[Problems to be solved by the invention]
In an anechoic chamber where the floor surface is a metal surface that is an electromagnetic wave reflection surface, if there are discontinuous parts such as joints on the floor surface, the performance of the anechoic room deteriorates due to radio waves being scattered by the discontinuous parts. . Therefore, it is desirable that there is no discontinuous portion such as a joint on the floor surface.
[0008]
However, as shown in FIG. 4, when the turntable 210 is provided so as to form a part of the floor surface 201, there is a gap between the outer peripheral portion of the turntable 210 and the surrounding floor portion 203. Will occur. Therefore, conventionally, by electrically connecting the outer peripheral portion of the turntable 210 and the floor portion 203 by an electrical connecting member 204 such as an earth roller, both are made the same potential surface, and a uniform reflecting surface is formed. I was trying to get it.
[0009]
As described above, the gap between the outer peripheral portion of the turntable 210 and the floor portion 203, the electrical connection between the outer peripheral portion of the turntable 210 and the floor portion 203 by the electrical connection member 204 such as an earth roller, etc. It is an important factor that affects the characteristics of the darkroom.
[0010]
However, conventionally, since the turntable 210 having a considerable size and weight is provided so as to form a part of the floor surface 201, there are many problems as follows.
[0011]
That is, first, there is a problem that the initial installation state of the turntable 210 and the secular change of the installation state adversely affect the characteristics of the anechoic chamber.
[0012]
Further, in order to rotate the large and heavy turntable 210, a large driving device 211 is required, and there is a problem that noise generated by the driving device 211 adversely affects the measurement.
[0013]
In particular, when the specimen 213 is small, there is a problem that the specifications of the turntable 210 are excessive, particularly in terms of the load capacity.
[0014]
The present invention has been made in view of such problems, and an object of the present invention is to provide an anechoic chamber turntable device that can reduce adverse effects on the characteristics of the anechoic chamber.
[0015]
[Means for Solving the Problems]
An anechoic chamber turntable device according to the present invention comprises a specimen table on which a specimen is placed and rotated, and a driving means that is disposed under the floor of the anechoic chamber and rotates the specimen table. The table is disposed above the floor surface of the anechoic chamber, and a mounting portion on which the specimen is mounted, and a shaft portion that protrudes downward from the lower surface of the mounting portion and is detachably connected to the driving means. It has.
[0016]
In the anechoic chamber turntable device of the present invention, the specimen table is detachably connected to the driving means by the shaft portion, and is rotated by being driven by the driving means.
[0017]
The anechoic chamber turntable device of the present invention may further include an opening formed on the floor of the anechoic chamber, through which the shaft portion of the specimen table is inserted, and a cover capable of opening and closing the opening. .
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an anechoic chamber to which an anechoic chamber turntable device according to an embodiment of the present invention (hereinafter simply referred to as a turntable device) is applied will be described with reference to FIG. FIG. 3 is a plan sectional view showing an example of the configuration of a test facility including an anechoic chamber. The test equipment shown in this figure is used to measure the radiated noise intensity of devices that generate noise that causes electromagnetic interference to other devices, or to test malfunctions by irradiating electronic devices with electromagnetic waves of strong electromagnetic fields. It is what is done.
[0019]
The test facility shown in FIG. 3 includes an anechoic chamber 110 and a measurement chamber 120 that is an electromagnetic shielding chamber for measurement disposed adjacent to the anechoic chamber 110. The anechoic chamber 110 is provided with a large shield door 111 for loading and unloading the test object, and a small shield door 112 for entering and leaving the measurement chamber 120.
[0020]
The anechoic chamber 110 has a floor 113, four walls 114, and a ceiling (not shown), all of which are provided with an electromagnetic shielding plate made of an electromagnetic shielding material. A radio wave absorber 115 is attached to the interior surface of the wall 114 and the ceiling. The floor 113 is provided with the turntable device 1 according to the present embodiment for rotating the specimen. Further, the floor 113 is provided with an antenna positioner 117 that is a place where an antenna is installed.
[0021]
The electromagnetic shielding material is a material having a large reflection coefficient (close to 1) and a small transmission coefficient (close to 0) with respect to electromagnetic waves in a desired frequency band, and corresponds to various metals, but steel materials are used. There are many.
[0022]
A radio wave absorber is a structure that has a small reflection coefficient and transmission coefficient (approximately 0) for radio waves in a desired frequency band and absorbs incident radio wave energy to convert it into thermal energy.
[0023]
The radio wave absorber 115 in FIG. 3 includes, for example, a tile-shaped ferrite radio wave absorber and a foamed polystyrene base radio wave absorber attached to the indoor surface of the ferrite radio wave absorber. A ferrite wave absorber is a wave absorber that utilizes the magnetic resonance loss of ferrite at high frequencies. The foamed polystyrene substrate wave absorber is configured by mixing carbon as a resistor with a foamed polystyrene substrate.
[0024]
Next, with reference to FIG. 1, the structure of the turntable apparatus 1 which concerns on this Embodiment is demonstrated. The floor 113 of the anechoic chamber 110 is formed with pits 2 for housing a driving device to be described later. The turntable device 1 is arranged in the pit 2 under the floor surface of the anechoic chamber 110 on which the specimen 30 is placed and rotated, and as a driving means for rotating the specimen table 10. And a driving device 20. In the pit 2, a utility space for storing the pseudo power supply device 21 and the like is provided. The pseudo power supply device 21 is a device constituting a pseudo power supply circuit network (also referred to as a power line impedance stabilization circuit network), and may be used for measuring interference waves.
[0025]
The specimen table 10 is arranged above the floor surface of the anechoic chamber 110 and has a placement part 11 on which the specimen 30 is placed, and a shaft part 12 protruding downward from the lower surface of the placement part 11. Have. The shaft portion 12 penetrates the floor surface and is detachably connected to the drive device 20. Further, at least a portion of the shaft portion 12 exposed on the floor is formed of a material that does not affect measurement, for example, wood.
[0026]
The opening of the pit 2 is closed by the metal plate 3. The metal plate 3 is formed with an opening 4 through which the shaft portion 12 of the specimen table 10 is inserted, and an opening disposed at a position above the utility space.
[0027]
Further, a metal cover 5 capable of opening and closing the opening 4 and a metal cover 6 capable of opening and closing the opening disposed at a position above the utility space are attached to the metal plate 3. FIG. 2 is a plan view showing the metal plate 3 and the covers 5 and 6.
[0028]
The power supply path 15 for supplying power to the specimen 30 is provided at the center of the shaft portion 12 using a slip ring, a mercury rotary, or the like.
[0029]
Next, the operation of the turntable device 1 according to the present embodiment will be described. When using the specimen table 10, as shown in FIG. 1, the opening 4 is opened and the shaft portion 12 of the specimen table 10 is connected to the drive device 20. A specimen 30 is placed on the placing portion 11 of the specimen table 10. By operating the driving device 20 in this state, the specimen table 10 rotates and the specimen 30 also rotates.
[0030]
When the specimen table 10 is not used, the shaft portion 12 is removed from the driving device 20 and the opening 4 is closed by the cover 5 as shown in FIG.
[0031]
In addition, normally, the opening disposed at a position above the utility space is closed by the cover 6, but is opened when maintenance is performed on the drive device 20, the pseudo power supply device 21, and the like.
[0032]
According to the present embodiment, the weight of the specimen 30 is limited to some extent, but a turntable device 1 that is particularly suitable for a lightweight and small specimen 30 can be realized.
[0033]
Further, according to the present embodiment, there is no conventional large turntable on the floor surface of the anechoic chamber 110, and therefore there is no gap between the floor surface and the turntable. Since it is only necessary to have a small opening 4 on the floor surface through which the shaft portion 12 of the specimen table 10 passes, the adverse effect on the characteristics of the anechoic chamber 110 can be reduced, and the characteristics of the anechoic chamber 110 can be improved.
[0034]
Moreover, according to this Embodiment, the electrical connection members, such as an earth roller, which electrically connects a floor surface and a turntable become unnecessary.
[0035]
Further, according to the present embodiment, when the specimen table 10 is not used, the opening 4 can be closed by the cover 5 to form a flat floor surface without a groove, that is, a radio wave reflection surface. Characteristics can be improved.
[0036]
Moreover, according to this Embodiment, since the clearance gap between the axial part 12 of the specimen table 10 and a floor surface is small, it depends on the bad initial installation state of the specimen table 10, and the secular change of the installation state. There are few adverse effects.
[0037]
Moreover, according to this Embodiment, since the specimen table 10 does not form a part of floor surface, the specimen table 10 can be reduced in weight. As a result, it is possible to use a small driving device 20. According to the present embodiment, in addition to this, since the gap between the shaft portion 12 of the specimen table 10 and the floor surface is small, the influence of noise generated by the drive device 20 can be reduced.
[0038]
Moreover, according to this Embodiment, since the drive mechanism of the specimen table 10 is simple, the maintenance of a drive mechanism becomes easy.
[0039]
In addition, this invention is not limited to the said embodiment, A various change is possible. For example, a portion of the shaft portion 12 of the specimen table 10 that is disposed under the floor is formed of metal, and the metal plate 3 and the metal portion of the shaft portion 12 around the opening 4 are electrically connected by an electrical connection member. May be connected to each other.
[0040]
【The invention's effect】
As described above, according to the turntable device for an anechoic chamber of the present invention , it is only necessary that the floor surface has a small opening through which the shaft part of the specimen table passes, so that the adverse effect on the characteristics of the anechoic chamber is reduced. There exists an effect that it can reduce.
[0041]
Further, according to the anechoic chamber turntable device of the present invention, the anechoic chamber turntable device includes an opening formed on the floor surface of the anechoic chamber and through which the shaft portion of the specimen table is inserted, and a cover that can open and close the opening. When the specimen table is not used, the opening can be closed to form a flat floor surface without grooves, thereby improving the characteristics of the anechoic chamber.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a turntable device according to an embodiment of the present invention.
2 is a plan view showing a metal plate and a cover in FIG. 1. FIG.
FIG. 3 is a plan sectional view showing an example of the configuration of a test facility including an anechoic chamber to which the turntable device according to one embodiment of the present invention is applied.
FIG. 4 is a cross-sectional view showing an example of the configuration of a conventional turntable.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Turntable apparatus, 2 ... Pit, 3 ... Metal plate, 4 ... Opening part, 5, 6 ... Cover, 10 ... Specimen table, 11 ... Mounting part, 12 ... Shaft part, 20 ... Drive apparatus, 21 ... Pseudo power supply device, 30 ... Specimen.

Claims (1)

A specimen table on which the specimen is placed and rotated;
Arranged below the floor of the anechoic chamber, and provided with driving means for rotating the specimen table,
The specimen table is disposed above the floor surface of the anechoic chamber and protrudes downward from the placement section on which the specimen is placed and is detachable from the driving means. A shaft portion to be connected,
Furthermore, provided with an opening formed on the floor of the anechoic chamber, through which the shaft portion of the specimen table is inserted , and a cover capable of opening and closing the opening ,
Inner diameter of the opening is rather smaller than the outer diameter of the mounting section,
When the specimen table is not used, the shaft section can be removed from the driving means and can be pulled out from the opening section .

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