JP4464881B2 - Silencer - Google Patents

Description

  The present invention relates to a silencer in an exhaust pipe of an internal combustion engine.

  Conventionally, environmental impacts caused by noise while working on ships, around harbors, and when anchored, because the main sound source has become higher exhaust gas due to the smaller and higher output of the internal combustion engine, so a small and highly sound-absorbing silencer Has been demanded.

  In the conventional passive silencer, the diffusion type that considers the pressure loss due to passage resistance has a low noise reduction effect for the center sound, and it is necessary to change the fluid direction of the exhaust gas many times in order to mute the center sound. The total passage distance caused a pressure loss (for example, Patent Documents 1, 2, 3, and 4).

JP 7-42530 A JP-A-9-88548 JP 2003-328723 A JP 2004-156555 A

It is an object of the present invention to mute the initial diffusion portion by immediately absorbing the initial diffusion exhaust gas into the small-diameter quadrangular cylinder on the center line inside the muffler muffler provided in the exhaust pipe of the internal combustion engine.

In order to achieve the above object, the present invention
First, the diameter of the muffler muffler connected to the exhaust pipe of the internal combustion engine on the common center line is larger than that of the exhaust pipe, and both ends closed small-diameter quadrangular cylinders are arranged on the common center line inside the muffler muffler, The space between the outer periphery of the small-diameter square tube and the inner periphery of the muffler is closed with a central partition plate, the outer periphery of the inlet-side closing plate of the both-ends closed small-diameter square tube is fixed to the inner peripheral surface of the muffler, A plurality of through holes are opened at symmetrical positions on the outer periphery of the closing plate , a plurality of suction through holes are formed in the side surface of the small-diameter square tube on the inlet side of the partition plate, and a plurality of suction holes are formed on the outlet side of the partition plate. A muffler comprising a sound absorbing material stretched on the inner peripheral surface of the muffler muffler between the partition plate and the muffler muffler outlet;
Silencer orderly arranged the said first invention, wherein a plurality of suction holes and the plurality of exhaust through holes in the second,
Consists of.

Therefore, the gas exhausted from the exhaust pipe enters the muffler muffler along the common center line, hits the inlet side closing plate, changes direction and hits the inner peripheral surface of the muffler,
Through a plurality of through holes press-fitted into the space between the smaller diameter square cylinder and the muffler, the muffler emits a slight vibration sound.

Pressed air in the space is pressed into orderly the square cylinder from a plurality of suction holes of small diameter square tube, the outlet side of the small diameter square tube without vibrating the cylindrical wall of the small diameter square tube Abutting against the closing plate to increase the entry pressure in the small-diameter square cylinder ,
The entering gas enters the outlet side space of the closing plate in the middle through the plurality of discharge through holes, the vibration of the exhaust gas is absorbed by the sound absorbing material, and the gas is silently discharged from the outlet to the outside of the muffler.

The present invention has vibration energy most of the internal diameter square tube silencer muffler without exhaust pressure within muffler muffler connected to an exhaust pipe structure was so internal combustion engine as described above vibrates the barrel of silencing muffler Since it is almost absorbed, there is an effect of obtaining a silent muffler.

  A silencer muffler 2 having a diameter larger than the diameter of the exhaust pipe 1 is arranged on the common center line c in the exhaust pipe 1 of the internal combustion engine, and the outlet flange 1 'of the exhaust pipe 1 and the flange 2a of the inlet 2' of the muffler 2 are opposed to each other. And tighten them with bolts.

Silencing muffler 2 is cylindrical, "provided the inlet 2 'and an outlet 2" outlet 2 arranged at both ends closure small square tube 3 to share intermediate the center line c of the small diameter square tube 3 thereof The outer periphery of the central portion and the inner periphery of the central portion of the muffler 2 are connected and fixed by an annular central partition plate 4 to close the inlet side and outlet side spaces s and s.

The diameter square tube 3 is fixed to the outer periphery of the inlet port side closure plate 8 to the inner peripheral surface of the muffler 2, and semi-circular arc of a plurality (in FIG. 2 4) in symmetrical positions on the outer periphery of the closure plate 8 Open the shaped holes 9, 9, 9, 9
A diffusion chamber 10 is formed in the muffler 2 between the closing plate 8 and the inlet 2 '.

A plurality of suction through-holes 5, 5, 5 ', 5' are regularly formed in the small-diameter rectangular tube 3 between the inlet-side closing plate 8 and the central partition plate 4, and the outlet-side closing plate 8 'and the above-mentioned A plurality of discharge through holes 6, 6, 6 ′, 6 ′ are formed in an orderly manner in the small-diameter square tube 3 with the central partition plate 4.

  A collecting chamber 11 leading to the outlet 2 ″ is interposed between the outlet side closing plate 8 ′ and the outlet 2 ″.

  A sound absorbing material 7 is stretched on the inner peripheral surface between the central partition plate 4 of the muffler muffler 2 and the outlet side end plate 2 b of the muffler 2.

  The suction through holes 5, 5 on the inlet 2 'side and the exhaust through holes 6, 6 on the partition plate 4 side are provided at the top and bottom shown in FIG. 1, and the suction through holes 5', 5 'on the partition plate 4 side and the outlet are provided. The discharge holes 6 'and 6' on the 2 "side are provided sideways as shown in Figs.

  That is, the exhaust gas that has entered from the exhaust pipe 1 through the inlet 2 ′ of the muffler muffler 2 diffuses in the diffusion chamber 10, and is separated and diffused evenly by the through holes 9, 9, 9, 9 at the outer periphery symmetrical position of the inlet side closing plate 8. Thus, the primary sound absorption is performed.

Next, in the space s (collecting chamber) between the inlet side closing plate 8 and the partition plate 4, the plurality of (four) suction through holes 5, 5, 5 ′, 5 ′ enter the small-diameter square tube 3. When sucked, the first-sound-exhausted exhaust gas resonates and enters the small-diameter quadrangular tube 3 to be secondarily absorbed.

The exhaust gas that has been secondarily absorbed is blocked by the outlet closing plate 8 'of the small-diameter rectangular tube 3 and discharged from the plurality (four) of the discharge through holes 6, 6, 6', 6 '. The sound-absorbing material 7 is thirdarily absorbed (third-order sound absorption).

The exhaust gas that is thirdarily absorbed is collectively decompressed in the collecting chamber 11 between the outlet-side closing plate 8 ′ of the small-diameter square tube 3 and the outlet 2 ″ to reduce the sound pressure.

As described above, the exhaust sound of the internal combustion engine diffuses in the diffusion chamber 10 and is separated by the outer peripheral through hole of the inlet side closing plate 8, further resonates from the space s into the small-diameter rectangular tube 3, and is absorbed by the sound absorbing material 7. Further, the sound pressure is reduced in the collecting chamber 11 and discharged from the outlet 2 ″ to the atmosphere.

  The present invention repeats the exhaust sound emitted with the exhaust gas as described above by repeating the diffusion, separation, assembly, interference, and sound absorption at a short distance, and by making the exhaust flow close to a unidirectional flow with less backflow direction, Since the noise reduction effect is enhanced and the pressure loss due to passage resistance is minimized, the structure can be used not only for ships but also for exhaust pipes of large or small internal combustion engines in land transportation vehicles such as trucks and buses.

It is a longitudinal cross-sectional view which shows the silencer of this invention. (B) The figure is a longitudinal end view taken along the line BB, (b) The figure is taken along the line BB, (c) The figure is taken along the line CC, (d) The figure is D- (E) The figure is a longitudinal end view by the EE line, (f) The figure is the longitudinal end view by the FF line, (g) The figure is the longitudinal end view by the GG line, H) The figure is a longitudinal end view along the line H-H.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exhaust pipe c Common center line 2 Silencer muffler 2 'Inlet 2 "Outlet 3 Both-ends closed small diameter square tube 4 Central partition plate 5, 5' Suction through-hole 6, 6 'Discharge through-hole 7 Sound absorbing material 8 Inlet-side closing plate 9 Through hole

Claims (2)

The diameter of the muffler muffler connected on the common center line to the exhaust pipe of the internal combustion engine is larger than the exhaust pipe,
A small-diameter square tube closed at both ends is disposed on a common center line inside the muffler muffler, and a space between the outer periphery of the small-diameter square tube and the inner periphery of the muffler is closed with a central partition plate,
Fixing the outer periphery of the inlet-side closing plate of the both-ends closed small-diameter square tube to the inner peripheral surface of the muffler, and opening a plurality of through holes at symmetrical positions on the outer periphery of the closing plate;
A plurality of suction through holes are formed in the side surface of the small-diameter quadrangular tube on the inlet side of the partition plate, and a plurality of discharge through holes are formed on the outlet side of the partition plate;
A silencer in which a sound absorbing material is stretched on the inner peripheral surface of the muffler muffler between the partition plate and the outlet of the muffler muffler.   The silencer according to claim 1, wherein the plurality of suction through holes and the plurality of discharge through holes are arranged in an orderly manner.

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