JPH03278598A - Sound insulation structure for communication equipment housing - Google Patents

Abstract

PURPOSE:To enhance the quality of sound insulation to the outside of a frame by forming a wall body in envelop structure which comprises an enclosed air chamber with a structural board with holes and an outer wall board. CONSTITUTION:A frame 1 is provided with a door 2 having a board 3 with countless large holes in the inner side of the door 2 and a punched hole 5 bored with countless small holes on an inner wall of a side wall. The frame 1 comprises integrally a door outer wall 6 and the large hole board 3 in envelop structure, thus forming an enclosed air chamber except for small holes 7 for air penetration. In the same manner, the side wall 4 and the small hole board 5 constitute the envelop structure in one piece. The large hole board 3 and the small hole board 5 are made of rigid materials, such as wood, plastics, and metal. The spring action of the envelop structural part 8 which constitutes the air chamber and the air mass in the holes 7 serve as a vibration system having its natural frequency and absorb sound waves similar to the natural frequency. Internal vibration energy is absorbed with the inner wall by forming a large number of holes and prevented so that it may not be diffused to outside as much as possible, thereby obtaining the effect of sound proof as the frame.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a housing structure for communication equipment, and particularly to a sound insulation structure as a soundproofing measure for equipment that generates noise inside.

[Conventional technology]

Conventionally, with this type of housing structure, efforts have been made to reduce the noise level of the noise source without compromising particularly effective soundproofing measures.

[Problem to be solved by the invention]

With the conventional housing structure described above, the disadvantages of reducing the noise level (vibration energy) of the noise source are:
For example, as with a cooling fan motor, there is a drawback that the air blowing capacity decreases due to a decrease in the rotational speed, resulting in poor efficiency in terms of cooling performance.

[Means to solve the problem]

The sound insulation structure of the communication equipment casing of the present invention has a perforated structure in which a plurality of air through holes having a specific thickness and a specific passage area are bored in the inner wall of the communication equipment casing forming a box. The sound insulation structure of the communication device housing of the present invention is provided with a structural plate, and the perforated structural plate and the outer wall plate form a bag structure that forms a sealed air chamber except for the air through hole. teeth,
The perforated structural plate is made of a rigid body.

Furthermore, in the sound insulation structure of the communication device housing of the present invention, the perforated structural plate and the outer wall plate are integrally formed.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

1 and 2 are a perspective view and a cross-sectional view of essential parts of an embodiment of the present invention.

The casing 1 has a large perforated plate 3 in which countless small holes are bored in the inner wall of the door 2, and a small perforated plate 5 in which countless small holes are formed in the inner wall of the side wall 4. The door outer wall 6 and the large perforated plate 3 form a bag structure part 8 which becomes a sealed air chamber except for the air penetration hole 7, and the side wall 4 and the small perforated plate 5 similarly form the bag structure part. Here, it is assumed that the large perforated plate 3 and the small perforated plate 5 are made of rigid bodies such as wood, plastic, metal, or the like.

The operating principle of this embodiment with such a configuration is based on the resonance phenomenon (Holm-Hertz resonance) that occurs between a closed air chamber and a tube that is open at one location. It resonates at a frequency determined by the equivalent spring constant of the air chamber and absorbs the vibration energy (acoustic energy) of the external air.

That is, the spring action of the bag structure 8, which is an air chamber, and the air mass in the hole 7 form a vibration system that has a natural frequency,
It absorbs sound waves similar to this. By forming a large number of these, the internal vibration energy is absorbed by the inner wall, and by preventing it from radiating to the outside as much as possible, a sound insulating effect can be obtained as a housing.

In this embodiment, the door 2, the large perforated plate 3, and the side wall 4 and the small perforated plate 5 are created separately and constructed into one wall body by welding, gluing, etc., but these are made from the beginning. It may be integrally molded.

〔Effect of the invention〕

As explained above, the present invention has the effect of attenuating vibration energy by making the inner wall of the casing a sound absorber that applies a resonance phenomenon, thereby improving sound insulation from the outside of the casing.

[Brief explanation of drawings]

1 and 2 are a perspective view and a cross-sectional view of essential parts of an embodiment of the present invention. 1... Housing, 2... Door, 3... Large hole plate, 4
...Side wall, 5...Small perforated board, 6...Door outer wall,
7... Hole, 8... Bag structure (air chamber).

Claims (3)

[Claims] 1. A perforated structural plate with a plurality of air through holes having a specific thickness and a specific passage area is provided on the inner wall of a communication equipment casing forming a box, and the perforated structural plate and the outer wall 1. A sound insulation structure for a communication equipment housing, characterized in that a wall body is formed by a plate to form a bag structure that becomes a sealed air chamber except for the air through hole. 2. 2. The sound insulation structure for a communication device casing according to claim 1, wherein the perforated structural plate is made of a rigid body. 3. 2. The sound insulation structure for a communication device casing according to claim 1, wherein the perforated structural plate and the outer wall plate are integrally formed.