JPH0577576U - Silencer - Google Patents

Abstract

(57) [Abstract] [Purpose] The interior of the container interposed between air ducts is divided by a partition with small holes, and one container provides a sound damping effect by expansion and resonance or two kinds of resonance, resulting in a compact and wide sound range. It is a muffler that silences. [Structure] A container 2 having a partition wall 4 is provided between upstream and downstream air ducts 7 and 8. The open end 9 of the air duct,
The first cavity 5 having the openings 10 facing each other has open ends 9, 10
The second cavity portion 6 further functions as a resonance chamber, depending on the size of the space D ₁ between them, which serves as an expansion chamber or a resonance chamber. Therefore, it becomes a compact silencer that silences a wide range of sounds.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a silencer attached to an intake / exhaust system of an internal combustion engine.

[0002]

[Prior Art]

 BACKGROUND ART Mufflers are attached to air ducts such as intake pipes and exhaust pipes of internal combustion engines. For example, as disclosed in Japanese Patent Publication No. 53-6296, it is known that a cavity is provided in the middle of an air duct and the resonance box and the cavity are connected by a connecting pipe.

[0003]

[Problems to be solved by the device]

 As shown in the above example, the independent resonance container and the container surrounding the duct are formed by connecting them with a connecting pipe, so that the space required for mounting is large, especially for automobile engines. It is limited and cannot be installed, or the layout becomes unreasonable, making installation difficult.

[0004]

[Means for Solving the Problems]

 The muffler of this invention divides the inside of one container by a partition having small holes, and an upstream air duct and a downstream air duct are provided through the container wall, and the open ends of both air ducts in the container. Are opposed to each other at intervals.

[0005]

[Action]

 The first hollow portion in the container, in which the ends of the upstream air duct and the downstream air duct are open, has both open ends facing each other with a space therebetween, and thus serves as an expansion chamber and serves as a muffler. When this distance is small, the first cavity portion becomes a resonance chamber, which has a remarkable sound absorbing effect for a limited frequency.

The second cavity communicating with the first cavity via the small hole of the partition wall serves as a resonance chamber and has a silencing effect different from that of the first cavity. This effect is great because it is in communication with the first cavity where the air duct is open and the sound pressure is high.

[0007]

【Example】

The silencer 1 shown in FIGS. 1 and 2 is provided with a cylindrical partition wall 4 having a small hole 3 concentrically inside a cylindrical container 2 made of synthetic resin and closed at both ends. An annular second hollow portion 6 is formed to provide an upstream air duct 7 and a downstream air duct 8 penetrating the wall surface of the container 2, and the open ends 9 and 10 of both air ducts face each other with a gap D ₁ therebetween. It is the one that was done. The first cavity portion 5 serves as an expansion chamber for the circulation of the air ducts 7 and 8, and the second cavity portion 6 serves as a resonance chamber communicating with the first cavity portion 5 through the small hole 3. When the distance D ₁ is sufficiently small with respect to the cross-sectional area of the air ducts 7 and 8, the first cavity portion 5 serves as a common chamber.

The muffler 21 shown in FIGS. 3 and 4 is made of a synthetic resin and has a partition wall 24 having a plate-like shape parallel to the axis and a small hole 23 provided inside a cylindrical container 22 having both ends closed. The cavity 25 and the second cavity 26 are formed. An upstream air duct 27 and a downstream air duct 28 are provided so as to penetrate the wall surface of the container 22, and open ends 29, 30 of both air ducts 27, 28 are opposed to each other in the first cavity portion 25, and a space D ₂ is provided. It was provided by. When the distance D ₂ is large, the first cavity 25 is an expansion chamber, when it is small, it is a resonance chamber, and the second cavity 26 is a resonance chamber.

The muffler 41 shown in FIGS. 5 and 6 has a shape similar to that of the muffler 1 shown in FIGS. 1 and 2, and the axis of the container 2 is placed in the second cavity portion 6 shown in FIGS. Is provided with an annular partition wall 42 that is perpendicular to the first partition resonance chamber 43 and the second partition resonance chamber 44, and both partition resonance chambers communicate with the first cavity 5. The holes 45 and 46 are provided. Therefore, there can be two types of resonance frequencies in the second cavity portion 6. Alternatively, as shown in the drawing, a gutter-shaped duct 47 covering the small hole 45 may be provided, and the first section resonance chamber 43 may be a resonance chamber that communicates with the first cavity 5 by a communication pipe. With the duct 47, the sound deadening range of the first section resonance chamber 43 can be adjusted.

A muffler 51 shown in FIG. 7 has a cylindrical container 2 having a cylindrical partition wall 4 similar to the muffler 1 shown in FIGS. 1 and 2, and a first cavity portion 5 and a second cavity portion 6 are formed. Further, the second cavity portion 6 is divided into a first division resonance chamber 54 and a second division resonance chamber 55 having a fan-shaped cross section by the two division walls 52 and 53 that are parallel to the axis of the container 2 and are radial inside the second cavity portion 6. Small holes 56 and 57, which are divided and communicate with the first hollow portion 5, are provided. Furthermore, if necessary, a gutter-shaped air duct 48 is provided as a communication pipe.

[0011]

[Effect of the device]

 The muffler of the present invention is provided with a partition wall in one container to form the first and second cavities, so that the muffling effect due to resonance with expansion or resonance having different frequencies can be achieved in one container. The silencer has a wide sound range and is compact, and is particularly suitable for automobile engines and the like.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment.

FIG. 2 is a transverse sectional view of the first embodiment (line AA in FIG. 1).

FIG. 3 is a transverse sectional view of the second embodiment (line BB in FIG. 4).

FIG. 4 is a vertical sectional view of a second embodiment.

FIG. 5 is a vertical sectional view of a third embodiment.

FIG. 6 is a transverse sectional view of the third embodiment (line CC in FIG. 5).

FIG. 7 is a cross sectional view of the fourth embodiment.

[Explanation of symbols]

 4, 24 Partition wall 7, 8, 27, 28 Air duct 3, 23, 45, 46, 56, 57 Small hole

Claims (1)

[Scope of utility model registration request] 1. A container comprising a partition having a small hole for partitioning the interior thereof, an upstream air duct and a downstream air duct penetrating the container wall, and the upstream end and the downstream end of the upstream air duct in the container. A silencer in which the open ends of the side air ducts face each other with a gap.