JPS5854242B2 - sound absorption exhaust device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound absorption/exhaust device that absorbs and eliminates the exhaust sounds of steam and various types of exhaust.

Conventionally, exhaust devices with a sound absorption effect that are connected to steam exhaust pipes or various exhaust pipes that discharge large amounts of steam are:
A simple structure has been used in which a sound absorbing material made of porous fiber material wrapped in a perforated plate is provided in the exhaust passage within the exhaust device.

However, since such conventional sound absorbing and exhaust devices use porous fiber materials for the sound absorbing material, when used for exhaust gas containing a large amount of steam, the sound absorbing material absorbs water, and the absorbed water is released. Because it is difficult to do so, the sound absorption effect is significantly reduced and corrosion inside the exhaust system is significantly accelerated.

Furthermore, since the cross-sectional area of the exhaust passage in the sound-absorbing material is almost constant, it has the disadvantage that although it is effective in absorbing sound in a narrow frequency range, it cannot absorb exhaust sound in a wide range of frequencies. .

The sound absorption/exhaust device of the present invention solves these conventional drawbacks and is capable of absorbing and canceling exhaust noise over a wide range of frequencies even when exhaust gas contains a large amount of steam. A chamber is provided and a plurality of ceramic sound absorbers are arranged in a cylindrical shape, and the space surrounded by the ceramic sound absorbers forms a sound absorption band that becomes an exhaust passage. A sound absorption system in which a plurality of sound absorption bands are connected and communicated to form a sound absorption and exhaust passage so that the total cross-sectional area of the exhaust passage of each adjacent sound absorption band in the exhaust direction forms a relationship of alternating sizes. This is an exhaust system.

More specifically, the structure of the present invention will be explained in detail based on FIG. 1 showing one embodiment. As shown in Fig. 2, an air chamber 4 is provided on the back side of a ceramic sound absorber 3 in which sized ceramic particles are bonded with a heat-resistant binder in a rectangular case 2. 3 is disposed in a cylindrical shape inside the housing 2 by support arms 5, and a space 6 in the center surrounded by the four ceramic sound absorbers 3 serves as an exhaust passage into which the exhaust inlet 1 flows. A sound absorption band A of height is formed.

In a housing 2' having the same shape as the pipe body 2 on the exhaust side of the sound absorption band A, an air chamber 4 is formed on the back surface of each ceramic sound absorber 3, and a plurality of ceramic sound absorbers 3 are mounted on the support arm 5. Nine sound absorbing unit bodies M are arranged in a cylindrical shape, and the space 6 inside the cylindrical part serves as an exhaust passage for exhaust gas flowing out from the exhaust passage in the sound absorption band A. Both ends of the cylindrical part except for the respective spaces 6 are hermetically sealed to form a sound absorption zone B of a predetermined height.

In this case, the total cross-sectional area of the exhaust passages of the nine sound-absorbing unit bodies M in the sound-absorbing band B is made smaller than the total cross-sectional area of one exhaust passage in the sound-absorbing band A.

Furthermore, a fourth
As shown in the figure, an air chamber 4 is formed on the back surface, and a plurality of ceramic sound absorbers 3 are arranged in a cylindrical shape by supporting arms 5, and a space 6 inside the cylindrical portion is connected to the exhaust passage of the sound absorption band B in the previous stage. Three sound-absorbing unit bodies N, which serve as exhaust passages for the exhausted exhaust gas, are arranged, and both ends of each cylindrical interior, excluding the respective spaces 6, which serve as exhaust passages, are hermetically sealed to a predetermined position. A sound absorption band C of height is formed.

In this case, three sound absorption units N in sound absorption band C
The total cross-sectional area of the exhaust passage is larger than the total cross-sectional area of the exhaust passages of the nine sound-absorbing unit bodies M in the sound-absorbing band B of the previous stage.

Further, as shown in FIG. 5, an air chamber 4 is formed on the back side of the pipe body 2'' on the exhaust side of the sound absorption zone C, and a plurality of ceramic sound absorbers 3 are held in the cylinder by the supporting arms 5. Thirty-six sound-absorbing unit bodies O each having a small cross-sectional area are arranged in a cylindrical shape, and the space 6 in the cylindrical shape serves as an exhaust passage for exhaust gas discharged from the exhaust passage in the sound-absorbing band C of the previous stage. Both ends of each of the cylindrical parts except for the space 6 are hermetically sealed to form a sound absorbing zone of a predetermined height.

In this case, the total cross-sectional area of the exhaust passages of the 36 sound-absorbing unit bodies O in the sound-absorbing zone is smaller than the total cross-sectional area of the exhaust passages of the three sound-absorbing unit bodies N in the preceding sound-absorbing zone C.

And four types of sound absorption bands A with different total cross-sectional areas of the exhaust passage,
B, C, and D are connected so that the total cross-sectional areas of the exhaust passages alternately form a relationship of size as shown in Fig. 1, and the exhaust passages of the respective sound absorption bands communicate with each other to form a sound absorption exhaust passage. This is an exhaust system.

Note that T is an exhaust dispersion plate made of a perforated plate that disperses the exhaust gas introduced into the exhaust device.

In the embodiment, sound absorption bands B and C are used.

Although sound absorbing unit bodies M, N, and 0 were used to form D, it is not necessarily necessary to use the unit bodies, and it is of course possible to construct a predetermined exhaust passage directly inside the complex.
Use of a unit body has the advantage that assembly is easy and arbitrary exhaust passage relationships can be obtained extremely easily.

In addition, as an example, the sound absorption band has a four-stage structure, but it is not necessarily limited to four stages, and may be a multi-stage structure of two or more stages. , C, and D have been shown as examples of combinations of 1, 9, 3, and 36 exhaust passages, but these can be selected and implemented as appropriate depending on the exhaust volume and the frequency range in which sound should be absorbed. be.

Further, the size of the air chamber on the back surface of the ceramic sound absorber can be appropriately selected depending on the frequency range to be absorbed.

Since the sound absorption/exhaust device of the present invention has the above-described configuration, noise is generated when the noise-accompanied exhaust is introduced from the exhaust inlet 1 at the bottom of the complex 2 or when it is ejected from the exhaust inlet. Exhaust air passes through the exhaust passage of sound absorption band B, which has a small cross-sectional area, than the exhaust passage of sound absorption band A, which has a large cross-sectional area and is surrounded by ceramic sound absorbers, and enters the exhaust passage of sound-absorption band C, which has a large cross-sectional area. The sound was then exhausted to the outside air through an exhaust passage with a small cross-sectional area around the sound absorption band.

Therefore, the noisy exhaust gas passes through the exhaust passages in the sound absorption bands with alternately large and small cross-sectional areas, while being repeatedly expanded and compressed. On the other hand, in a sound absorption band with a small cross-sectional area, relatively high frequency noise is absorbed and canceled.

Furthermore, since the sound absorbing body is made of a ceramic sound absorbing body, for example, even if the exhaust gas contains a large amount of steam, there is almost no decrease in the sound absorption coefficient, and moisture can be drained extremely easily. , almost no internal corrosion occurs.

As described above, the sound absorbing exhaust device of the present invention uses a ceramic sound absorber as a sound absorbing material, and furthermore, the exhaust passage surrounded by the ceramic sound absorber has a plurality of sound absorbing bands having different total cross-sectional areas.

This is a sound absorption/exhaust device in which a sound absorption/exhaust passage is formed that connects and communicates with the total cross-sectional area force so as to form a magnitude relationship with each other.

If the ceramic sound absorbing plate is extruded or cast, the cylinder can be integrally formed, but as the length of one side of the cylinder increases, it becomes difficult to integrally form the cylinder by extrusion or casting. Therefore, integral molding of the sound absorber has a limit in its size, and there are many problems in terms of cost and processing.

Therefore, ceramic sound absorbers are usually in the form of a flat plate, and since there is a limit to their size for mass production, it is better to use multiple ceramic sound absorbers, for example, four ceramic sound absorbers, rather than making a large cylindrical body with one piece. It is easier to manufacture and cheaper to combine to create an integral cylindrical body with a large cross section.

In the present invention, one of the reasons for disposing a plurality of ceramic sound absorbers is to simplify manufacturing and reduce manufacturing costs.

When making a plate or tube by combining multiple ceramic sound absorbers, it is more effective to change the material and type of the sound absorbers.

Since the air chamber is generally smaller and partitioned, the sound absorption field is better, so it is easier to attach the support arm 5 when the air chamber is formed from a plurality of sound absorbers.

Therefore, the second purpose of forming the exhaust passage with a plurality of ceramic sound absorbers is to improve the sound absorption effect.

In addition, when a plurality of ceramic sound absorbing plates are used to partition one exhaust hole into four chambers, one cylindrical body is formed by four ceramic sound absorbing plates, and one cross section is formed by arranging four ceramic sound absorbing plates. In this way, it is better to combine a plurality of ceramic sound absorbers than one from the viewpoints of improved strength, ease of repair and inspection, etc.

Therefore, depending on the type of exhaust, the size of the air chamber on the back side of the ceramic sound absorber, the size of the total cross-sectional area of the exhaust passage of each sound-absorbing band, the number of adjacent sound-absorbing bands and the relationship between the total cross-sectional areas, etc. can be arbitrarily selected. As a result, it can be used as a sound absorption device for various types of exhaust.For example, there is no decrease in the sound absorption coefficient even for exhaust that contains a large amount of steam, and it can also be used reliably against exhaust noise over a wide range of frequencies. It can exhibit sound absorbing properties and can be used as a sound absorbing device for humid exhaust gas and various types of exhaust gas, making it an extremely useful exhaust device for industrial purposes and noise pollution prevention.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram of one embodiment of the present invention, and FIG.
3 is a sectional explanatory diagram of sound absorption band A in FIG. 1, FIG. 4 is a sectional explanatory diagram of sound absorption band C in FIG. It is a cross-sectional explanatory view of a sound absorption band. 1...Exhaust inlet, 2, 2', 2", 2"'
... Cone, 3 ... Ceramic sound absorber, 4
...Air chamber, 5...Support arm, 6...
...Space, 7...Exhaust dispersion plate, A. B, C, D... Sound absorption band, M, N, 0...
...Sound absorption unit body.

Claims (1)

[Claims] 1. Inside a housing made of sound insulating material, an air chamber is provided on the back side and a plurality of ceramic sound absorbers are arranged in a cylindrical shape, and the space surrounded by the ceramic sound absorbers forms a sound absorption band that serves as an exhaust passage. The plurality of sound absorption bands having different total cross-sectional areas of the exhaust passages are connected so that the total cross-sectional areas of the exhaust passages of the respective sound absorption bands adjacent to each other in the exhaust direction alternately form a relationship in size. A sound absorption and exhaust device characterized by forming a sound absorption and exhaust passage that communicates with each other.