A SILENCER FOR VEHICLE

Technical Field

[1] The present invention relates to a silencer for vehicle, and more particularly to a silencer for vehicle that enhances output and suppresses noise by making pipes in a straight line so that exhaust gas may be directly discharged without refraction.

Background Art

[2] Generally, a silencer for vehicle includes a cylindrical body 10 made of a steel plate, an inlet pipe 20 inserted into the body 10 from one of its circular side and supported and fixed by a plurality of barriers 11, an outlet pipe 30 formed at the other side symmetrically to the inlet pipe 20 not to be overlapped but crossed with the inlet pipe 20 and supported and fixed by a plurality of the barriers 11, a plurality of barriers 11 positioned in the body 10 at regular intervals to fix the inlet pipe 20 and the outlet pipe30 in the body 10 and have a predetermined discharge hole 1 Ia at the center, and a chamber 12 having an inner space by means of the barriers 11, as shown in Fig. 4.

[3] Such a conventional silencer for vehicle is now described in more detail. In the silencer, an exhaust gas initially introduced into the inlet pipe 20 passes through a plurality of chambers 12 formed by the barriers 11 and then collided with an inner wall 10a of the body at the opposite side to be reflected. This reflected exhaust gas is again moved through the discharge hole 11a prepared at the center of the barriers toward an inner wall 10b of the body where the exhaust gas was initially introduced. The moved exhaust gas is refracted again by the inner wall 10b of the body and then introduced into the outlet pipe 30 inserted into the body 10, then discharged out. As described above, in the conventional silencer for vehicle, while an exhaust gas refractively passes through the chambers 12 formed by means of a plurality of barriers 11, its pressure and temperature are decreased. In addition, since the exhaust gas is moved via the discharge hole 11a, pressure and temperature are deteriorated to suppress abrupt expansion and explosion sound.

[4] However, since an exhaust gas is refractively discharged in the body 10, such a silencer for vehicle does not ensure smooth discharge flow, thereby deteriorating the output of vehicle. In addition, due to the separated pipes (e.g. the inlet pipe 20 and the outlet pipe 30), noise is not efficiently suppressed. Moreover, since the barriers 11 supporting the pipes (e.g. the inlet pipe 20 and the outlet pipe 30) are shaken while the vehicle is driving, noise may become rather serious. Meanwhile, the exhaust gas may be condensed when it is not smoothly exhausted, which causes many problems like that a condensed liquid (or, water) may be gathered in the body to make the pipe rusty.

[5]

Disclosure of Invention Technical Problem

[6] The present invention is designed to solve the problems of the prior art, and therefore an object of the invention is to provide a silencer for vehicle that is capable of enhancing output and suppressing noise by making pipes in a straight line so that exhaust gas may be directly discharged without refraction.

[7]

Technical Solution

[8] In order to accomplish the above object, the present invention provides a silencer for vehicle, a cylindrical body made of a steel plate and having an introduction hole formed in one side and an discharge hole formed in the other side to have a center on the same line as the introduction hole 100 in a length direction; a chamber installed in the body and having a plurality of holes in an circumferential surface thereof, one open side of the chamber being fixed by welding to one side of the body, the other closed side of the chamber being a steel plate through a center of which an end pipe is partially passed, the steel plate having a plurality of holes except a portion cor¬ responding to the end pipe; a separation plate having a plurality of holes, the separation plate being fixed to one side of a guide at a center and having a discharge hole, the separation plate being fixed to one side in the chamber to separate the chamber and a reduction unit; a first reduction unit one side of which is extended from the discharge hole of the separation plate and the other side of which is fixed in correspondence to the introduction hole of the body, the first reduction unit having a plurality of holes formed in a circumferential surface thereof; a main pipe one side of which is positioned near the introduction hole in the first reduction unit and the other side of which is inserted into one side of the end pipe so as to be crossed a predetermined length, the side of the main pipe inserted into the end pipe being curved to be integrated and sealed thereto; a second reduction unit forming a decompression portion by an inner circumference of the end pipe and an outer circumference of the main pipe when the main pipe is inserted into and crossed with the end pipe, one side of the second reduction unit where the decompression portion is formed being inserted through the chamber, the second reduction unit having a plurality of reduction holes at regular intervals in an circumferential surface of the end pipe where the decompression portion is formed; a inner pipe extended from the second reduction unit toward the discharge hole and having a large number of holes therein, the end pipe being configured by winding a stainless wool up to a predetermined thickness around the second reduction unit; and a sound-absorbing material filled between the outer cir-

cumference of the inner pipe mounted in the body and the inner circumference of the body.

Advantageous Effects

[9] This silencer for vehicle improves output and reduces noise by control of pressure and temperature of the exhaust gas by the chamber and the reduction unit by configuring the inner pipe in a straight line so that an exhaust gas may be discharged directly without curving.

[10]

Brief Description of the Drawings

[11] These and other features, aspects, and advantages of preferred embodiments of the present invention will be more fully described in the following detailed description, taken accompanying drawings. In the drawings:

[12] Fig. 1 is a partially-sectioned perspective view showing a silencer for vehicle according to the present invention;

[13] Fig. 2 is a horizontally sectioned view showing the silencer for vehicle according to the present invention;

[14] Fig. 3 is a sectional view showing a discharge flow of an exhaust gas according to the present invention; and

[15] Fig. 4 is a sectional view showing a discharge flow of an exhaust gas in the prior art.

[16]

Best Mode for Carrying Out the Invention

[17] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[18] As shown in Figs. 1 to 3, a silencer for vehicle according to the present invention is configured so that a main pipe 400 and an end pipe 500 are straightly formed to have the same horizontal center on a straight line from introduction to discharge of an exhaust gas. An exhaust gas initially introduced through an introduction hole 100 is divided into three routes at a first reduction unit 300a of a inner pipe 200, and the exhaust gas is then discharged with sound absorption through the following three routes.

[19]

[20] First Route: introduction hole → main pipe → end pipe → discharge hole

[21]

[22] An initial exhaust gas introduced through the introduction hole 100 of the body 10 is sucked into an introduction hole 410 of the main pipe 400 with a smaller diameter than the introduction hole 100 due to the pressure difference. This introduced exhaust

gas is discharged to a discharge hole 420 via a certain region of the main pipe 400. At this time, a certain portion near the discharge hole 420 of the main pipe 400 is inserted into the end pipe 500, and the inserted end of the main pipe 400 is curved to be integrated with the end pipe 500. If the exhaust gas reaches the integrated portion in the main pipe 400, pressure and temperature of the exhaust gas are decreased when the exhaust gas moves from the main pipe 400 to the end pipe 500 since a diameter of the end pipe 500 becomes larger than that of the main pipe 400. The exhaust gas with decreased pressure and temperature is discharged out through a discharge hole 110 via a certain region of the end pipe 500. That is to say, the exhaust gas is discharged without refraction, thereby obtaining efficient output.

[23]

[24] Second Route: introduction hole → guide → discharge hole → chamber → reduction hole → end pipe

[25]

[26] A part of the exhaust gas not introduced into the main pipe 400 at the first reduction unit 300a is directly moved into an adjacent chamber 210b through an expanded guide 310a and a discharge hole @320b formed in the outer circumferential surface of the main pipe 400 and the first reduction unit 300a. At this time, due to diameter of the expanded guide 310a and the discharge hole 320a, the exhaust gas is moved with its pressure and temperature decreased. The adjacent chamber 210b to which the exhaust gas with decreased pressure and temperature is moved has a large space to decrease pressure and temperature more effectively. In particular, the exhaust gas is sucked into a decompression portion 320b positioned in a plurality of reduction holes 310b formed in the circumferential surface of the end pipe 500 that is integrally fixed to the steel plate 220 at the sealed side of the chamber 210 and partially inserted into the chamber 210b. A second reduction unit 300b configured as above decreases pressure due to pressure difference of the exhaust gas directly flowing through the main pipe 400 and the end pipe 500 with a smaller diameter than the space in the chamber 210b, and then introduces the decompressed exhaust gas into the decompression portion 320b. In particular, since the plurality of reduction holes 310b have small diameter, the exhaust gas in the chamber 210b is rapidly introduced into the end pipe 500. Meanwhile, when the exhaust gas is moved as mentioned above, residual exhaust gas and exhaust noise except the exhaust gas introduced into the reduction holes 310b in the chamber 210b are discharged through the plurality of holes 240 formed in the steel plate 220 and the side of the chamber 210b. The residual exhaust gas and exhaust noise discharged through the holes 240 as mentioned above are absorbed in a sound-absorbing material 120 fully filled between the body 10 and the outer surface of the inner pipe 200 including the chamber 210, thereby reducing noise. The residual exhaust gas and noise

reduced by the sound-absorbing material 120 as mentioned above are introduced into the end pipe 500 by means of a plurality of holes 510 formed in the end pipe 500. It is also resulted from pressure difference of the exhaust gas moving in the end pipe 500. At this time, a stainless wool 520 is wound around the circumferential surface of the end pipe 500 having the holes 510, so the residual exhaust gas and the reduced exhaust noise are reduced again and then introduced. The residual exhaust gas and noise reduced twice are discharged out through the end pipe 500.

[27] Third Route: introduction hole → holes → chamber → chamber → reduction hole

→ end pipe

[28]

[29] As a final way of the exhaust gas, the exhaust gas flowed in through the in¬ troduction hole is moved by means of a plurality of holes 250 formed in the circum¬ ferential surface of the first reduction unit 300a and then introduced into the chamber 210a. At this time, pressure and temperature of the exhaust gas are decreased due to wide space of the chamber 210a. Such an exhaust gas is not rapidly moved into the adjacent chamber 210b by means of a separation plate 230 separating the chambers 210a and 210b and having a plurality of holes 240. In particular, the exhaust gas that is moved to the adjacent chamber 210b via a plurality of holes 240 formed in the separation plate 230 is encountered and mixed with the exhaust gas in the chamber 210b mentioned in the second route and then introduced through the reduction hole 310b formed in the second reduction unit 300b. After that, the exhaust gas is discharged out from the end pipe 500 by means of the decompression portion 320b. At this time, residual exhaust gas and exhaust noise are also discharged out by means of a plurality of holes 240 formed in the side of the chamber 210a. The residual exhaust gas and exhaust noise discharged through the holes 240 as mentioned above are absorbed into the sound-absorbing material 120 fully filled between the body 10 and the outer surface of the inner pipe 200 including the chamber 210, thereby reducing noise. In addition, the residual exhaust gas and exhaust noise reduced by the sound-absorbing material 120 experience noise reduction by the stainless wool 520 wound around the end pipe 500, similarly to the second route, and then the residual exhaust gas and noise are introduced through a plurality of holes 510 formed in the end pipe 500 and discharged out through the discharge hole.

[30] Such a silencer for vehicle has an integrated pipe and puts the introduction hole 100 and the discharge hole 110 in a straight line, differently from the prior art. Thus, when an exhaust gas is discharged, resistance is minimized. In addition, since the inner structure of the silencer is directly communicated, the noise may be effectively reduced by means of the reduction unit 210 and the sound- absorbing material 120.

[31]

Industrial Applicability

[32] As described above, the silencer for vehicle according to the present invention configures the inner pipe in a straight line so that an exhaust gas may be discharged directly without curving, thereby improving output and reducing noise by control of pressure and temperature of the exhaust gas by the chamber and the reduction unit.