KR101614072B1 - Reactive low static pressure silencer - Google Patents

Abstract

The present invention discloses a reflection type low-pressure silencer capable of improving a noise attenuation effect by a laminated structure of a plurality of holes having different numerical apertures. The present invention includes a body conduit, first and second cover plates, at least one inlet-side manifold and an outlet-side manifold, a middle manifold, and a plurality of divider plates. The body conduit has a first open end, a second open end and a body passageway for air flow. The first cover plate is coupled to the body conduit to close the first open end and has an inlet passage communicating with the body passage. The second cover plate is coupled to the body conduit to close the second open end and has an exit passage communicating with the body passage. And a plurality of holes communicating with the inlet-side resonance chamber for attenuating the frequency of use frequency, the inlet-side resonance chamber being mounted in a body passage adjacent to the inlet passage to form an inlet-side resonance chamber and having an inner passage communicating with the inlet passage, Is formed on the outer surface so as to have an aperture ratio of 46%. And a plurality of holes communicating with the exit-side resonance chamber for attenuating a used-frequency sound, the other-side tube being disposed in the body passage adjacent to the exit passage so as to form an exit-side resonance chamber and having an inner passage communicating with the exit passage, Is formed on the outer surface so as to have an aperture ratio of 46%. The middle pipe is installed in the body passage between the inlet pipe and the outlet pipe so as to form an expansion chamber. The inner pipe has an inner passage communicating with the inner passage of the inlet pipe and the inner passage of the outlet pipe. , And a plurality of holes communicating with the expansion chamber for low-frequency noise attenuation are formed on the outer surface so as to have an aperture ratio of 25%. The plurality of partition plates are mounted between the inlet-side cavity and the outlet-side cavity, respectively, so as to partition the inlet-side resonance chamber, the outlet-side resonance chamber, and the expansion chamber, respectively.

Description

 REACTIVE LOW STATIC PRESSURE SILENCER [0002]

The present invention relates to a silencer, and more particularly, to a reflection type low-pressure silencer capable of enhancing a sound attenuation effect by a laminated structure of a plurality of holes having different numerical apertures.

The problem of environmental damage due to noise is increasing due to the high output and high capacity of blower, compressor, and engine, and systems for creating a quiet environment are mandated by mandatory indication of noise level. Especially, not only the performance of the machine but also the low noise has a great influence on the quality competitiveness and it is a main criterion for selecting the product according to the buyer. As technological requirements for such low noise are strengthened, development of low weight and high performance silencers is required.

On the other hand, mufflers are developed in various forms and structures. The silencer can be classified into Reactive, Resistive or Absorptive, Reactive-Resistive depending on the operating principle and should be selected according to the purpose of noise attenuation or attenuation.

Generally, the reflection type silencer attenuates noise by reflecting the acoustic energy emitted from the noise source toward the noise source due to the impedance mismatch caused by the change of the area of the flow path. Reflective silencers are known to effectively attenuate noise in the low and mid frequency regions. The reflective silencer is also called an expansion silencer.

The disappearing silencer uses a sound absorbing material on the wall surface of the flow path to dissipate acoustic energy to thermal energy. The disappearing silencer is also called a sound absorber silencer. The sound absorbing material may be contaminated by fungi and bacteria, and it may be scattered, so it should be replaced periodically. Therefore, it is difficult to manage the replacement of the sound absorbing material and the maintenance cost increases. In particular, the sound absorbing material is easily obstructed by the air supply and exhaust including the sticky air supply and dust, and has the disadvantage of lowering the ventilation performance and the noise reduction efficiency. The reflection and disappearance type silencer is most widely used as a combination of a disappearance type and a reflection type in order to satisfy space and conditions as much as possible.

As an example of the reflection type silencer, Korean Patent No. 10-1024372 entitled " Silencer for ventilation using interference and expansion phenomenon of sound waves "includes a body, an inlet tube, an outlet tube, a plurality of separation plates, and a plurality of expansion tubes. The space inside the body is divided by the separating plates and the expansion pipes, so that the sound is introduced and discharged, and branching, joining, compression and expansion occur in the process of discharging the sound, so that the noise in the wide frequency range can be attenuated.

The conventional silencer has a disadvantage in that the cross-sectional area and shape of the passages for the air flow are changed by mounting the separators and the perforated plates, so that the pressure loss due to the vortex is generated and the noise attenuation effect is lowered. In addition, since the cross-sectional area of the passages is changed by mounting the separators and the perforated plates, the structure inside the body is complicated and the assemblability is greatly deteriorated.

The present invention is intended to solve various problems of the conventional muffler. SUMMARY OF THE INVENTION An object of the present invention is to provide a new reflective low-pressure silencer capable of improving the noise attenuation effect by the laminated structure of the other holes having different aperture ratios.

Another object of the present invention is to provide a reflective low-pressure silencer capable of minimizing a pressure loss by a structure having no cross-sectional area and shape change for air flow.

It is still another object of the present invention to provide a reflective low-pressure silencer that is simple in structure and can be manufactured in a light weight.

According to an aspect of the present invention, there is provided a reflective low-pressure silencer. The reflective low-pressure silencer according to the present invention includes a main body conduit, first and second cover plates, at least one inlet-side manifold and outlet-side manifold, a middle manifold, and a plurality of partition plates. The body conduit has a first open end, a second open end and a body passageway for air flow. The first cover plate is coupled to the body conduit to close the first open end and has an inlet passage communicating with the body passage. The second cover plate is coupled to the body conduit to close the second open end and has an exit passage communicating with the body passage. The inlet-side pipe is mounted in a body passage adjacent to the inlet passage so as to form an inlet-side resonance chamber between the inner wall surface and the outer surface of the body conduit, and has an inner passage communicating with the inlet passage, And a plurality of holes communicating with the inlet-side resonance chambers for noise attenuation are formed on the outer surface so as to have an aperture ratio of 46%. And the other communicating tube at the outlet side is mounted in a body passage adjacent to the outlet passage so as to form an exit-side resonance chamber for attenuating sound between the inner wall surface and the outer surface of the body conduit and has an inner passage communicating with the outlet passage, A plurality of holes communicating with the exit-side resonance chamber for noise attenuation are formed on the outer surface so as to have an aperture ratio of 46%. And the other central pipe is mounted in a body passage between at least one inlet-side pipe and at least one outlet-side pipe, so as to form an expansion chamber between the inner wall surface and the outer surface of the main body conduit, And a plurality of holes communicating with the expansion chamber for low frequency noise attenuation are formed on the outer surface so as to have an aperture ratio of 25%. The plurality of partition plates are installed between at least one inlet-side cavity, at least one outlet-side cavity, and the middle cavity, respectively, so as to partition the inlet-side resonance chamber, the outlet-side resonance chamber, and the expansion chamber.

The reflection type low-pressure silencer according to the present invention can improve the sound attenuation effect by mounting the other holes having different opening ratios in the body passage in a laminated structure, The pressure loss can be minimized by the structure. In addition, the structure in which ducts and other pipes constituting the silencer are manufactured by sheet metal is simple and lightweight can be produced.

1 is a perspective view showing a configuration of a reflection type low-pressure silencer according to the present invention.
2 is a perspective view illustrating the structure of a reflective low-pressure silencer according to the present invention.
3 is a cross-sectional view showing a configuration of a reflection type low-pressure silencer according to the present invention.
FIG. 4 is a perspective view illustrating the configuration of the other manifolds and partition plates in the reflective low-pressure silencer according to the present invention. FIG.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of a reflective low-pressure silencer according to the present invention will be described in detail with reference to the accompanying drawings.

1 to 3, a reflective low-pressure silencer according to the present invention includes a body duct 10 in the form of a rectangular tube. The body conduit 10 has a first open end 12 and a second open end 14 formed at both ends and a first open end 12 and a second open end 14 for air flow And a body passage 16 formed therein. The body conduit 10 can be made of sheet metal, for example, a metal sheet, as a base material. The body conduit 10 can be easily manufactured in accordance with the cross-sectional area, length, etc. of the flow channel by the sheet metal of the body conduit 10, thereby improving the degree of freedom in designing the body conduit 10.

The reflective low attenuating silencer according to the present invention includes a first cover plate 20 coupled to a body conduit 10 to close a first open end 12 of the body conduit 10, And a second cover plate (30) coupled to the body conduit (10) to close the second open end (14) of the body conduit (10). Each of the first and second cover plates 20 and 30 may be coupled to the body conduit 10 by screwing, riveting, welding, or the like. Each of the first and second cover plates 20 and 30 can be made of sheet metal like the body conduit 10. The first and second cover plates 20 and 30 are preferably formed in the same size and shape.

The inlet passage 22 is formed at the center of the first cover plate 20 so as to communicate with the body passage 16. [ And an outlet passage 32 is formed in the center of the second cover plate 20 so as to communicate with the body passage 16. [ The sectional areas of the inlet passage 22 and the outlet passage 32 are substantially the same. The inlet passageway 22 is connected to the ventilator duct system 40 by way of an air blower 42 or a ventilator and an inlet conduit 44, for example. An outlet conduit 46 for the discharge of air is connected to the outlet passage 32. In some embodiments, the blower 42 may be connected to the outlet side conduit 44 instead of the inlet side conduit 44.

3 and 4, the reflective low-pressure silencer according to the present invention includes a plurality of inlet-side holes 50 mounted in the body passage 16 of the body conduit 10, (60) and a middle other pipe (70). The other inlet conduits 50 are mounted in the body conduit 16 so as to be adjacent to the inlet conduit 22.

The other exit conduits 60 are mounted in the body passage 16 so as to be adjacent to the exit passage 32. Each of the inlet pipes 50 and the outlet pipes 60 is connected to the body passage 16 in a group of three. In some embodiments, the number of each of the inlet pipes 50 and the outlet pipes 60 may be appropriately adjusted depending on the characteristics and conditions of the noise. And the other side pipe 70 is mounted in the main body passage 16 so as to be disposed between the other side pipe 50 at the inlet side and the other pipe 60 at the outlet side.

Each of the inlet side, outlet side and middle intermediate tubes 50, 60 and 70 is formed in the form of a rectangular tube having inner passages 52, 62 and 72 arranged at the center of the body passage 16. The cross-sectional area and shape of the inner passages (52, 62, 72) are generally the same as those of the inlet and outlet passages (22, 32).

Each of the inlet side and outlet side tubes 50 and 60 is connected to the body conduit 10 to form inlet and outlet side resonance chambers 54 and 64 for noise attenuation between the inlet side and outlet side tubes 50 and 60, Is spaced from the inner wall surface (18) of the base plate (10). That is, the body passage 16 is partitioned into the inner passages 52, 62 and the resonance chambers 54, 64 by mounting of the other side tubes 50, 60 at the inlet side and the outlet side. Like the other inlet pipes 50 and the outlet pipes 60 are formed so as to form an expansion chamber 74 for attenuating sound between the inner pipe wall 70 and the inner wall face 18 of the body conduit 10, Is spaced from the inner wall surface (18) of the conduit (10).

Each of the inlet pipes 50 and the outlet pipes 60 is constructed in the same manner as the plate of the perforated plate in which a plurality of holes 56, 66 are formed so as to have an aperture ratio of 40 to 50% have. And the aperture ratio of each of the other openings 50, 60 on the inlet side and the outlet side is preferably about 46%. The diameter of the holes 56, 66 is about 5 mm. The thickness of the perforated plate may be less than 0.8 mm. The middle pipe 70 is made of sheet metal of a perforated plate in which a plurality of holes 76 are formed to have an aperture ratio of less than 20 to 30% for low-frequency noise attenuation. The diameter of the holes 76 is about 40 mm.

The reflective low attenuating silencer according to the present invention includes the inlet side and outlet side separate tubes 50 and 60 and the middle other tube tubes 70 and 70 so as to partition the inlet side and outlet side resonance chambers 54 and 64 and the expansion chamber 74 And a plurality of partition plates (80) mounted between the respective partition plates (80). And an engaging hole 82 is formed at the center of each of the partitioning plates 80. Each of the inlet pipes 50 and the inlet pipes 50 and 60 and the center pipe 70 are fitted into the fitting holes 82 and are engaged with each other.

The air blown by the blower 42 is introduced into the main passage 16 through the inlet-side conduit 44 and the inlet passage 22 in the reflective low-pressure silencer according to the present invention having the above- And then passes through the inner passage 52 of the other inlet conduits 50 at the inlet. Noise is attenuated while being reflected on the inner surfaces of the inlet-side holes 50. Part of the noise also passes through the small holes 56 into the wide resonance chambers 54 or cavities between the inner wall surface 18 of the body conduit 10 and the outer surface of the inlet side other apertures 50 And is attenuated while being reflected by the inner wall surface 18 of the body conduit 10 and the outer wall surfaces of the inlet side perforated plates 50. The inlet-side apertures 50 having an aperture ratio of about 46% possess the characteristics of an expandable silencer effective for attenuation of the used frequency noise by the action with the surrounding resonance chambers 54.

Subsequently, the noise passed through the inlet-side conduits 50 passes through the small holes 72 and passes through the wide resonance chamber 54 between the inner wall surface 18 of the body conduit 10 and the outer surface of the middle conduit 70 ) And then attenuated by resonance action. In the middle of the aperture ratio of about 25%, the perforated tubes 70 retain the characteristics of a resonant silencer effective for attenuating low-frequency noise by acting with the surrounding expansion chamber 74. It is general that the resonance effect disappears and the characteristic of the expansion silencer is retained when the opening ratio of the other pipe 70 in the middle is 30% or more. The reflection type low-pressure silencer according to the present invention can reduce 8 dB / m or more in the 160 Hz band when the capacity is 2,104 l.

Meanwhile, in the reflective low-pressure silencer according to the present invention, the sectional shapes of the inner passages (52, 62, 72) connecting between the inlet passage (22) and the outlet passage (32) . When the cross-sectional shape of the passage for the air flow is changed, a vortex is generated near the change point to generate a pressure loss, and the pressure loss becomes larger as the change in cross-sectional shape is larger and the number of changes is larger. The pressure loss can be maintained at less than about 1.2 mmAq by the reflective low-pressure silencer according to the present invention.

In order to investigate the pressure loss of the reflection type low-pressure silencer according to the present invention, the inlet side, the outlet side, and the middle central pipes (50, 60, 70) 16, and the pressures for the examples after the inlet side, the outlet side, and the middle side tubes 50, 60, and 70, respectively, were installed in the main passage 16 were measured and shown in Table 1. From Table 1, it can be seen that there is almost no pressure loss in the examples.

division Comparative Example Example Air flow rate (m / s) 5 10 5 10 Pressure (hPa) 0.01 0.01 0.06 0.11

The reflective low-pressure silencer according to the present invention has a simple structure in which the inlet side, the outlet side, and the middle pipe 50, 60, 70 are installed in the body passage 16, When weighing about 860kg can be made. Generally, when the capacity of the disappearing silencer using a splitter having a sound absorbing material is 2,104 L, the weight of the disappearing silencer is about 2,000 kg, It can be made about 50% lighter than the silencer. Further, since the reflective low-pressure silencer according to the present invention does not use a sound-absorbing material, it can be efficiently used for an adhesive supply / discharge unit, an air-supply unit including dust, and the like.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: body conduit 16: body conduit
20: first cover plate 22: inlet passage
30: second cover plate 32: outlet passage
40: Ventilation duct system 50: Entrance side
52, 62, 72: inner passage 54: inlet side resonance chamber
56, 66, 76: hole 60:
64: exit side resonance chamber 70:
74: expansion chamber 80: partition plate

Claims (3)

A body conduit having a first open end, a second open end and a body passageway for air flow;
A first cover plate coupled to the body conduit to close the first open end, the first cover plate having an inlet passage communicating with the body passage;
A second cover plate coupled to the body conduit to close the second open end and having an exit passage communicating with the body passage;
An inner passage communicating with the inlet passage and mounted in the body passage adjacent to the inlet passage so as to form an inlet side resonance chamber between the inner wall surface and the outer surface of the body conduit, At least one inlet-side porous pipe formed on the outer surface so that a plurality of holes communicating with the inlet-side resonance chamber for attenuation have an aperture ratio of 46%;
And an inner passage communicating with the outlet passage and mounted in the body passage adjacent to the outlet passage so as to form an outlet-side resonance chamber between the inner wall surface and the outer surface of the body conduit, One or more exit-side apertures formed on the outer surface so that a plurality of holes communicating with the exit-side resonance chamber for attenuation have an aperture ratio of 46%;
Wherein the at least one inlet-side vent pipe and the at least one outlet-side vent pipe are mounted in the body passage between the inner wall surface and the outer surface of the body conduit so as to form an expansion chamber for attenuating sound, A plurality of holes communicating with the expansion chamber for low frequency noise attenuation are formed on the outer surface so as to have an aperture ratio of 25%, the inner hole having an inner passage communicating with the inner passage of the one or more outlets and the inner passage of the at least one outlet, A private embassy;
A plurality of partition plates mounted between the at least one inlet-side cavity tube and each of the at least one outlet-side cavity tube and the middle cavity tube so as to partition the inlet side resonance chamber, the outlet side resonance chamber, and the expansion chamber, Includes a reflective hypotonic silencer. The method according to claim 1,
Wherein the inlet passageway, the outlet passageway, the one or more inlet-side other passageways, the one or more outlet-side passageways, and the inner passageways of the other passageways have the same cross-sectional area. delete

Images