KR20130008321A - Muffler with multi-resonator for construction equipment - Google Patents

Abstract

The present invention relates to a muffler for construction equipment for inserting a multi-resonator, an object of the present invention is to provide a multi-resonator insertion silencer that can reduce the noise of various frequency bands by providing a multi-resonator inside the silencer to reduce the exhaust gas noise of the engine There is.
The configuration of the present invention is a cylindrical silencer case (1); An exhaust gas inlet pipe 2 having a porous structure penetrating laterally of the case 1; The first baffle 4 of the disc structure, in which the wood pipe 13 is installed, which is installed at one end of the case and is spaced apart by a predetermined interval to form a first resonator 3 which isolates the space part and reduces the noise of the main frequency band. and; A second disc-shaped disc structure having a wood pipe 15 formed to be spaced apart from the other end of the case by a predetermined interval to isolate the space to form a second resonator 5 which reduces noise of a frequency band different from the first resonator. Baffle 6; A third baffle (11) and a fourth baffle (12) installed between the first baffle (4) and the second baffle (6) to isolate a space inside the case; An exhaust gas outlet 19 installed through a case in an upper portion of a space formed by the third and fourth baffles 11 and 12; It is installed in the longitudinal direction of the case is blocked both side ends penetrating any one or more of the first, second, third, fourth baffle (4, 6, 11, 12) and the circumference of the first, third, fourth Multiple resonator insertion silencer for construction equipment comprising a porous pipe (7, 8, 9, 10); characterized by the invention.

Description

Muffler with multi-resonator for construction equipment

The present invention relates to a silencer for construction equipment in which multiple resonators are inserted that can reduce noise in various frequency bands, and more particularly, to a silencer that significantly reduces exhaust noise by inserting multiple resonators into a silencer for construction equipment. .

In general, automobiles and construction equipment, etc. are equipped with various types of silencers to reduce the exhaust gas noise emitted from the engine.

Types of such silencers include reflection, interference, interference reflection, absorption, absorption reflection, and resonance.

Reflective silencer is a silencer configured to attenuate noise by impact reflection by blocking the path of pulsating exhaust gas several times by arranging several spaces continuously and installing through pipes in the partitions forming each space.

The interference silencer is a silencer configured to remove noise by weakening the energy of exhaust gas because the exhaust pipe has a structure of repeating branching and aggregation.

The interference reflection compound silencer is a silencer configured to reflect exhaust noise through several sound pipes and partitioned spaces and to simultaneously attenuate and attenuate the collection.

Absorption silencer is a silencer composed of several partition spaces, partially perforated silencer and porous sound absorbing material to reduce the noise by introducing exhaust gas into the sound absorbing material inserted into the partition space through the hole perforated in the sound pipe.

Resonant silencers are designed to reduce the volume of the exhaust by designing dimensions and shapes suitable for reducing exhaust noise, using the helmholtz resonance principle.

Here is a brief introduction to the principle of helmholtz resonance. 7 is a diagram illustrating a general helmholtz resonance principle, which is a principle disclosed in the prior art portion of Korean Patent Application No. 10-2005-7020861. Hereinafter, reference numerals in FIG. 7 use reference numerals of a corresponding specification for convenience of description.

Referring to the drawings, the Helmholtz resonator is a chamber having an open throat. The amount of air located in the chamber and the neck vibrate because of the periodic compression of the air in the chamber. Such Helmholtz resonators can be attached to the exhaust pipe of an internal combustion engine and cancel out the noise (usually 30 to 400 Hz) caused by the ignition of the piston of the internal combustion engine. Helmholtz resonator 54 and a rigid outer comprising a necked portion 54a having an inner diameter D _T , a length L _T , and a chamber portion 54b having an inner diameter D _C , a length L _C shown. Shown schematically is a muffler 50 comprising a shell 52. Typically, the peak attenuation frequency of the sound energy, i.e., the frequency at which the transmission loss is maximum, is a function of the volume of the neck having the chamber portion 54b, the inner diameter D _T , and the length L _T of the Helmholtz resonator 54. . For example, if the chamber volume increases and the neck with inner diameter D _T , length L _T remains the same, the peak attenuation frequency decreases and if the chamber volume decreases, the peak attenuation frequency increases. When the Helmholtz resonator 54 is attached as a side branch, the side branch has both mass (inertia) and compliance. This acoustic system is a so-called Helmholtz resonator and works very much like a simple mass spring damping system. This resonator has a diameter (D _T ), an area (S _b ), a neck with an effective neck length (L _eff ) and a cavity volume (V) (function of D _C and L _c ) of L + 0.85D _T. Include. Cavity volumes resonate in frequency and, during the process of resonance, interact with energy. All of the energy absorbed by the resonators in some of the acoustic cycles is returned to later pipes in the cycle. A phase relationship is one in which energy is returned back towards the source, ie not sent down the duct. Since no energy is removed from the system, the actual part of the branch impedance R _b is zero. Virtual part of the impedance is expressed in the resonator compliance and inertia point of _{view, X b = p (wL eff} / S b - c 2 / wV), lunar transfer coefficient (sound power transmission coefficient) is as in equation (1) Is created.

식 (1)

Formula (1)

The transmitted force is w = w ₀ equals ₀ in Equation (1), when the resonant frequency of the resonator is all reflected back toward the source. These filters reduce the sound in the resonant frequency circumferential band and pass all other frequencies. The narrow frequency range in which interference occurs is not a desirable condition in automobile exhaust, since the frequency of acoustic energy changes as the engine speed (RPM) changes and the temperature of the exhaust gas changes.

An application structure of a general resonance silencer among the various silencers as described above is shown in FIG. 8. 8 is a technique disclosed in the prior art of the Republic of Korea Utility Model Application No. 20-1996-0067175. Hereinafter, reference numerals in FIG. 8 use reference numerals of a corresponding specification for convenience of description. As shown there is a complex multi-stage separation structure consisting of a three-way catalytic device 107, a front silencer 109 and a rear silencer 111 connected by an exhaust manifold 103 and a bellows tube 105, of which It is the rear silencer 111 that represents a resonator for attenuating main frequency noise. However, since the silencer configured as a separate type of the resonator has to be additionally equipped with a separate silencer such as the rear silencer 111 to remove the noise of the main frequency band, the work process is increased, thereby increasing the cost.

The prior art in which the resonator structure is integrally inserted into the silencer by solving such a problem is Korean Utility Model Application No. 20-1996-0067175 shown in FIG. The technology is characterized by the installation of a totally resonant noise reduction device in a single small silencer with a small cross-sectional area, which reduces the number of parts and work processes due to the addition of a silencer and simplifies the method of manufacturing the silencer. Hereinafter, reference numerals in FIG. 9 use reference numerals of the specification for convenience of description.

According to the configuration, the inlet pipe forming a case 3 and a plurality of through holes 5 through the outer circumferential surface thereof are inserted into the space 10 partitioned by the baffle 7 inside the case 3. (11) is inserted into the space (13) partitioned by the baffle (9) and another baffle (9), and a plurality of through holes (15) are formed through the outer circumferential surface thereof and the opposite side of the inlet pipe (11) is guided. The branch pipe 21 divided into the outlet pipe 19 through which the pipe 17 and the plurality of through holes 25 penetrate, and the outlet pipe 19 of the branch pipe 21 are formed by the baffle 9. It consists of the sound absorption material 27 enclosed by the outer peripheral surface exposed to the partitioned complete resonance chamber 23.

Although the conventional silencer with attenuating branch pipes, that is, the integrated silencer with a resonator, has many advantages, only a part of the exhaust gas is introduced into the resonator through the branch pipe corresponding to the 'neck' structure of the Helmholtz resonator. Noise can be blocked, and the remaining exhaust gas is exhausted, so the capacity of the entire exhaust gas is weak for large construction equipment,

In addition, since only one frequency noise component selected from various noises can be reduced, there is a disadvantage in that expansion power such as attenuation ability for various frequency noises is weak.

An object of the present invention for solving the above problems is to provide a multi-resonator insertion silencer having a resonator inside the silencer to reduce the exhaust gas noise of the engine can attenuate the noise of various frequency bands.

It is another object of the present invention to provide a multi-resonator insertion silencer having a plurality of Helmholtz resonator structures that can attenuate a lot of exhaust gas noise generated from an engine with a larger engine output than an automobile such as construction equipment.

The present invention to achieve the object as described above and to perform the problem for eliminating the conventional defects and a cylindrical silencer case;

An exhaust gas inlet pipe having a porous structure penetrating the side of the case;

A first baffle having a disc structure having a wood pipe installed thereon to be spaced apart from one end of the case to isolate the space to form a first resonator for reducing a target frequency noise;

A second baffle having a wood plate formed disc structure, which is installed at the other end of the case to be spaced apart by a predetermined interval to isolate the space and form a second resonator for reducing the frequency noise different from the first resonator;

Third and fourth baffles disposed between the first and second baffles to isolate a space inside the case;

An exhaust gas outlet formed through the case at an upper portion of the space formed by the third and fourth baffles;

The first porous pipe and the second porous pipe, which are installed in the lengthwise direction of the case and are closed at both ends of the first baffle, the second baffle, the third baffle, and the fourth baffle, and have a periphery around the block. It is achieved by providing a multi-resonator insertion silencer for construction equipment, characterized in that comprising ;, a third porous pipe and a fourth porous pipe.

In a preferred embodiment of the present invention, the first porous pipe and the second porous pipe may be installed at one side of the first baffle and the other side of the first porous pipe and the second porous pipe at the fourth baffle.

In a preferred embodiment of the present invention, the third porous pipe and the fourth porous pipe may be installed at one side of the third baffle and the other side of the third and fourth porous pipes.

According to an embodiment of the present invention, the separation distance between the first baffle and the second baffle forming the first resonator and the second resonator has a different separation distance, and has a different spatial volume, and the first baffle and the first resonator Woodwinds formed on the two baffles may be formed to have different lengths and cross-sectional areas.

In a preferred embodiment of the present invention, a plurality of wood pipes formed on the first and second baffles may be formed.

As described above, the present invention is provided with two resonators inside the silencer, by configuring the chamber capacity of the different capacity and the advantage that can be reduced together with two or more frequency band noise in one silencer,

In addition, the resonance system is provided with a plurality of Helmholtz neck structures in which the exhaust gas flows into the chamber of the resonator so that the noise of the main frequency band of the exhaust gas of the capacity generated from the engine having a larger engine output than that of a vehicle, such as construction equipment, is reduced. It is a useful invention having the advantage of increasing the efficiency of the exhaust gas noise treatment by the invention is that the invention is expected to be greatly used.

1 is a cross-sectional view showing a structure of a multi-resonator insertion silencer according to an embodiment of the present invention,
Figure 2 is an exemplary side view showing a multi-resonator insertion silencer structure according to an embodiment of the present invention,
3 is a cross-sectional view taken along line AA ′ of FIG. 1;
4 is an exemplary view showing a first baffle according to an embodiment;
5 is an exemplary view illustrating a second baffle according to an embodiment;
6 is an exemplary view illustrating third and fourth baffles according to an embodiment;
7 is an exemplary view showing a general helmholtz resonance principle,
8 is an exemplary view showing a separate silencer using a conventional resonator,
9 is an exemplary view showing an integrated silencer in which a conventional resonator is inserted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a cross-sectional view showing a multi-resonator insert silencer structure according to an embodiment of the present invention, Figure 2 is a side view showing a multi-resonator insert silencer structure according to an embodiment of the present invention, Figure 3 1 is a cross-sectional view taken along line A-A ', 4 is an exemplary view showing a first baffle according to an embodiment, FIG. 5 is an exemplary view showing a second baffle according to an embodiment, and FIG. 6 is an embodiment. The figure shows the 3rd, 4th baffle which followed.

As shown, the multi-resonator insertion silencer of the present invention has a hole formed in one direction of the cylindrical silencer case (1) through which the exhaust gas inlet pipe (2) of the porous structure receives the exhaust gas discharged from the manifold of the engine It is installed through this radial direction. The exhaust gas inlet pipe 2 is formed in a porous structure in which a plurality of holes are perforated on the surface thereof so that the exhaust gas is discharged into the case 1.

The case 1 has a plurality of disc-shaped baffles formed therein to isolate and divide the internal space.

Specifically, the plurality of baffles according to the present invention may be installed at one side end of the case to be spaced apart by a predetermined interval to form a first baffle having a disc structure to form a first resonator (3) having a space volume to reduce the noise by separating the space part ( 4) and a second baffle (6) of disc structure, which is installed at a distance apart from the other end of the case to form a second resonator (5) which isolates the space part and reduces noise of a frequency band different from the first resonator. And a plurality of first porous tubes 7 installed between the first baffle 4 and the second baffle 6 in the same length direction as the case 1 for reducing noise and filtering pollutants while isolating a space. ), The second porous pipe 8, the third porous pipe 9, and the fourth porous pipe 10 are composed of a third baffle 11 and a fourth baffle 12 installed therethrough.

The first resonator and the second resonator have different space volumes to reduce noise of various frequency bands by the principle of the Helmholtz resonator.

The first porous pipe 7, the second porous pipe 8, the third porous pipe 9, and the fourth porous pipe 10 have a porous structure only in the circumferential direction, and both sides of the first porous pipe 7, the second porous pipe 8, and the fourth porous pipe 10 are closed. The gas is configured to be discharged only through the porous structure in the circumferential direction.

The exhaust gas inlet pipe 2 is installed between the first baffle 4 and the third baffle 11.

The first porous tube 7, the second porous tube 8, the third porous tube 9 and the fourth porous tube 10, which are the plurality of porous tubes, are provided in different positions on the baffle.

First, the first porous pipe 7 and the second porous pipe 8 are positioned inside the case 1 in a vertical direction in a cross direction with respect to the exhaust gas inlet pipe 2 having a porous structure located at the center thereof. It is installed in the first baffle 4 and the other side is installed in the fourth baffle 12 through the third baffle 11.

In addition, the third porous pipe 9 and the fourth porous pipe 10 are installed in one side direction of the exhaust gas inlet pipe 2 of the porous structure, the first porous pipe (7), the second installed in the vertical direction The porous pipe 8 is provided symmetrically in the left-right direction in which it is not located. The first porous tube 7 and the second porous tube 8 are installed in contact with the third baffle 11 at one side thereof and in contact with the second baffle 6 through the fourth baffle 12. do.

In addition, a plurality of resonator wood tubes 13 protruding toward the first resonator 3 are formed in the first baffle 4. In the figure, two are formed at the left and right. In addition, the first baffle allows the porous tube hole 14 to be drilled up and down to allow the first porous tube 7 and the second porous tube 8 to penetrate.

In addition, the second baffle 6 is provided with a plurality of resonator wood pipe 15 protruding toward the second resonator (5). In the figure, three are formed in a triangular structure. In addition, the second baffle has a perforated hole 16 in the left and right to penetrate the third and fourth perforated pipes 9 and 10.

According to the present invention, the separation distance between the first baffle and the second baffle forming the first resonator and the second resonator has a different spacing distance, and has a different space volume, and the wood pipe formed in the first baffle and the second baffle is formed. By having different lengths and cross-sectional areas, the noise of various frequency bands based on the principle of the Helmholtz resonator is reduced. That is, the role of the mass formed by the cross-sectional area and length of the wood pipe depends on the relationship between the spring role provided by the air by the volume of the space formed by the first and second resonators, and the frictional resistance of the air passing through the wood pipe. As the resonance occurs, it is converted into thermal energy with intense vibration, thereby reducing the acoustic energy. Since this description itself is the principle of the general Helmholtz resonator, the above-mentioned contents are sufficient, and the Helmholtz resonator principle itself is not invented in the present invention, and thus, further details will be omitted.

In addition, the third and fourth baffles 11 and 12 include a porous pipe hole for the first porous pipe 7, the second porous pipe 8, the third porous pipe 9, and the fourth porous pipe 10. 17 and 18 are formed to support the first porous tube 7, the second porous tube 8, the third porous tube 9 and the fourth porous tube 10.

An exhaust gas outlet 19 penetrating the case is formed in the upper portion of the space formed by the third baffle 11 and the second baffle 6, through the first resonator 3 and the second resonator 5. Exhaust gas with reduced noise in various frequency bands is emitted.

In addition, sound absorbing materials 20 and 21 made of fiberglass are installed at one end and the other end of the first resonator 3 and the other end contacting the case where the baffles of the second resonator 5 are not installed. Will be reduced.

It looks at the sound absorption process in the first and second resonators using the exhaust gas flow path and Helmholtz resonance of the present invention configured as described above.

The exhaust gas of each cylinder discharged during the combustion of the engine is supplied to the exhaust gas inlet pipe 2 through a manifold located at the top of the engine, and the first baffle 4 and the third baffle through the porous structure of the exhaust gas inlet pipe. Part of the exhaust gas discharged into the space provided by (11) flows into the first resonator through a plurality of wood pipes 13 formed in the first baffle 4, and after a specific frequency is reduced, it is discharged through the wood pipe again. Part of the exhaust gas flowing into the first porous pipe 7 and the second porous pipe 8 and not flowing into the first resonator is introduced through the pores of the first porous pipe 7 and the second porous pipe 8. .

The introduced exhaust gas is discharged to one side end region of the first porous pipe 7 and the second porous pipe 8, that is, the space formed by the third baffle 11 and the fourth baffle 12, and then the third gas is discharged. It is introduced through the pores formed in the vacant pipe 9 and the fourth porous pipe 10.

Since the exhaust gas introduced into the third porous pipe 9 and the fourth porous pipe 10 is partially discharged into the space formed by the fourth baffle 12 and the second baffle 6, the second baffle 6 is disposed. Through the wood pipe 15 formed in the second resonator (5) is introduced into the second resonator and a structure having a volume portion different from the first resonator due to the noise of the various frequency bands are reduced and discharged again formed in the upper portion with the remaining exhaust gas It is exhausted through the outlet 19.

Exhaust gas passing through the silencer of the present invention as described above can process up to two specific frequencies in one silencer by going through two resonators having different space volumes, and when the exhaust capacity discharged with construction equipment is large. Edo through multiple stages of the discharge flow path through the first resonator and the second resonator is multi-vented to increase the noise reduction performance.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. Of course, such changes will fall within the scope of the claims.

Description of the Related Art
(1): case (2): exhaust gas inlet pipe
(3): first resonator (4): first baffle
(5): the second resonator (6): the second baffle
(7): first perforated tube (8): second perforated tube
(9): third perforated tube (10): fourth perforated tube
(11): third baffle (12): fourth baffle
(13, 15): Woodwind (14, 16, 17, 18): Perforated Hall
(19): discharge port (20, 21): sound absorbing material

Claims (5)

A cylindrical silencer case 1;
An exhaust gas inlet pipe 2 having a porous structure penetrating laterally of the case 1;
A first baffle (4) of a disc structure provided with a wood tube (13), which is installed at one end of the case at a predetermined interval to form a first resonator (3) which isolates the space and reduces a specific frequency;
A second baffle of disc structure having a wood pipe 15 formed thereon, the second baffle having a wood pipe 15, which is installed at a predetermined distance from the other end of the case to form a second resonator 5 that isolates the space part and reduces noise of a frequency band different from the first resonator. (6);
A third baffle (11) and a fourth baffle (12) installed between the first baffle (4) and the second baffle (6) to isolate a space inside the case;
An exhaust gas outlet 19 installed through a case in an upper portion of a space formed by the third and fourth baffles 11 and 12;
Both sides of the case are installed in the lengthwise direction of the case and penetrate one or more of the first baffle 4, the second baffle 6, the third baffle 11, and the fourth baffle 12. Silencer for a multi-resonator insertion construction equipment comprising a; first porous pipe (7), second porous pipe (8), third porous pipe (9) and fourth porous pipe (10) consisting of a structure; .
The method according to claim 1,
The first porous tube 7 and the second porous tube 8 is characterized in that one side is installed in the first baffle 4, the other side is installed in the fourth baffle 12 through the third baffle 11. Silencer for construction equipment with multiple resonator inserts.
The method according to claim 1,
The third porous pipe 9 and the fourth porous pipe 10 have one side installed in the third baffle 11, and the other side penetrated through the fourth baffle 12 and installed in the second baffle 6. Muffler for construction equipment with multiple resonator inserts.
The method according to claim 1,
The separation distance between the first baffle and the second baffle forming the first resonator and the second resonator may be set differently to have different spatial volumes,
The wood pipe formed in the first baffle and the second baffle is a silencer for a multi-resonator insertion construction equipment, characterized in that formed to have a different length and cross-sectional area.
The method according to claim 1,
The wood pipe (13) formed in the first baffle and the second baffle is characterized in that a plurality of resonator insert construction equipment, characterized in that a plurality is formed.

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