JP3561146B2 - Windproof screen - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a windproof screen that covers a measurement microphone and prevents the influence of wind noise.
[0002]
[Prior art]
Conventionally, as a windscreen, for example, a windscreen described in JP-A-54-173737 is known. This windproof screen has a spherical main body made of a porous soft material such as urethane foam or woven fabric. Since this windscreen is spherical, it has the ability to suppress wind noise generated by wind from all directions.
[0003]
[Problems to be solved by the invention]
However, when measuring noise in a flat place where there are no buildings, hills, etc. in the vicinity, for example, airports, the wind direction is often horizontal, and the windscreen described above is adapted to all wind directions. For this reason, the spherical shape may be a problem.
[0004]
That is, when the wind direction is horizontal, if the wind is formed in a spherical shape, the airport noise in the low range cannot be accurately measured unless the wind is weak to a certain extent. On the other hand, when the wind is strong, turbulence is generated on the downstream side, and the turbulence hits the surface of the windproof screen, so that the microphone can detect wind noise of a level that cannot be ignored.
[0005]
The present invention has been made in view of the above-described problems of the conventional technology, and has as its object to prevent wind noise from entering a microphone even under a relatively strong wind. To provide a windscreen that can accurately measure low-frequency noise.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 has a flat wind-symmetric screen, a wind-screen main body whose thickness is gradually reduced toward the periphery, and a rotational symmetry axis of the wind-screen main body. And a supporting member for supporting the vertical direction.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a sectional view of a windproof screen according to the present invention.
[0008]
As shown in FIG. 1, the windscreen according to the present invention has a flat rotationally symmetrical shape, and the windproof screen main body 1 whose wall thickness is gradually reduced as approaching the peripheral edge, and the windproof screen main body 1 is rotationally symmetric. It is composed of a support column 2 that supports the axis so that it is aligned with the vertical direction and at a predetermined height position in the space. Further, a foundation 3 is provided in the ground so that the support pillar 2 stands upright on the ground, and an end of the support pillar 2 is embedded in the foundation 3.
[0009]
Inside the windproof screen main body 1, a space 1a for accommodating the microphone 4 is formed. Further, the windproof screen main body 1 is formed of a soft member such as urethane foam or nonwoven fabric.
[0010]
The microphone 4 is arranged such that the center axis of the microphone 4 is coincident with the axis of symmetry of the windscreen main body 1, and that the detection surface of the microphone 4 is located substantially in the center of the space 1 a formed inside the windscreen main body 1. , At the end of the support column 2.
[0011]
The operation of the windproof screen according to the present invention configured as described above will be described.
The windproof screen main body 1, which is formed in a flat rotationally symmetric shape and whose thickness gradually decreases as approaching the periphery, is supported such that its rotational symmetry axis coincides with the vertical direction. Since the microphone 4 is arranged in the internal space 1a, generation of turbulent flow on the leeward side is suppressed even if wind from a substantially horizontal direction blows to some extent, so that wind noise enters the microphone 4. Can be prevented. Therefore, when the wind direction is the horizontal direction, highly accurate noise measurement can be performed.
[0012]
In the above-described embodiment, a case has been described in which the cross-sectional shape of the windproof screen main body 1 is substantially rhombic and rotationally symmetric.
However, any other shape, for example, a double-sided convex lens shape, may be used as long as it has a flat rotationally symmetric shape and gradually becomes thinner toward the periphery . Also, in the cross-sectional shape, the upper and lower shapes do not necessarily have to be in a mirror mapping relationship.
[0013]
【The invention's effect】
As described above, according to the first aspect of the present invention, even when the wind blows from the horizontal direction, the windbreak screen main body has a flat rotationally symmetrical shape , and the wall thickness is gradually reduced toward the periphery . This suppresses the generation of turbulence on the leeward side of the windscreen main body, so that highly accurate noise measurement can be performed.
[Brief description of the drawings]
FIG. 1 is a sectional view of a windproof screen according to the present invention.
DESCRIPTION OF SYMBOLS 1 ... Windscreen main body, 1a ... Internal space, 2 ... Support pillar, 3 ... Foundation, 4 ... Microphone.

Claims (1)

It has a flat, rotationally symmetrical shape, and is composed of a windproof screen main body whose thickness gradually decreases as approaching the periphery, and a support member that supports the windproof screen main body so that the axis of rotational symmetry coincides with the vertical direction. A windproof screen characterized by the following.

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