JP3527962B2 - Silencer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler for use in, for example, an exhaust system of an automobile, and particularly to reduce exhaust noise formed by the flow of exhaust gas of high temperature and high pressure. The present invention relates to a silencer.

[0002]

2. Description of the Related Art A conventional silencer, particularly a sound absorbing silencer, is formed by a part of an exhaust pipe connected to an exhaust manifold as shown in FIG. The inner cylinder 10 having the above, the filter layer 20 made of metal fiber or the like wound around the outer cylinder of the inner cylinder 10 where the small holes 110 are provided, and the filter layer 20 are provided on the outside of the filter layer 20 in a close contact state. The sound absorbing material 30 made of glass wool or the like, and the small hole 11 provided outside the sound absorbing material 30.
0, the filter layer 20, the sound absorbing material 30, etc., and the outer cylinder 5 formed so as to seal the whole.
It is basically composed of 0 and.

[0003]

By the way, in the above-mentioned conventional one, the sound absorbing material 30 is provided on the outside of the filter layer 20, and at the inner cylinder 10 of such a silencer. When the hot exhaust gas flows in at a high speed, a part of the sound absorbing material 30 made of glass wool or the like is partially destroyed by the high heat, and at the same time, the inner cylinder 10 is heated by the high speed exhaust gas flow. It may be sucked in and discharged to the outside of the silencer. In order to solve such a problem, it is necessary to keep the filter layer 20 in a high density state and tightly wind it around the inner cylinder 10. Therefore, there is a problem in that the entire assembling work, including this tightly winding work, becomes complicated and the workability is not good. Further, there is a problem in that the mass of the entire filter is increased by setting the filter layer 20 at a high density. In order to solve such a problem, it is an object of the present invention to provide a muffling device that uses a muffling material that is light and excellent in assembling (assembling) and also serves as a filter layer. ).

[0004]

In order to solve the above-mentioned problems, the following measures are taken in the present invention. That is, according to the first aspect of the invention, in regard to a muffler for reducing exhaust noise, an exhaust gas is introduced and an inner cylinder having a large number of small holes in the outer peripheral portion and a myriad of fine metal wires. And a sound deadening member formed in a ring shape having a predetermined width by a predetermined forming means, and
A plurality of the ring-shaped sound deadening members are arranged in parallel at the outer peripheral portion of the inner cylinder having the small holes in a state in which they are in close contact with each other in the axial direction. A predetermined closed space is provided at the outer peripheral portion of the ring-shaped sound deadening member, and a heat insulating layer made of a predetermined heat insulating material having a predetermined thickness is provided outside the closed space, and the heat insulation is performed. It was decided to adopt a configuration in which an outer cylinder for holding the layers in a sealed state is provided.

By adopting such a constitution, in the present invention, when there is no sound absorbing material such as glass wool around the inner cylinder, when the exhaust gas flows at high speed in the inner cylinder, There is no inconvenience that the sound absorbing material such as the glass wool is sucked out and discharged to the outside of the silencer, that is, to the outside. Further, it becomes possible to form a sound deadening layer by fitting (attaching) a sound deadening member having a predetermined ring shape to the outside of the inner cylinder, and this single sound deadening member can be used as a small hole in the inner cylinder. By appropriately installing a number in the place where is provided, it becomes possible to contribute to the silencing of the target sound range (frequency). That is, in the present invention, by appropriately installing the above-mentioned muffling members, it becomes possible to achieve the muffling effect of sounds in various sound ranges (frequency), and thereby the characteristics of the muffling device can be freely adjusted. You will be able to tune to. Further, since a heat insulating layer in a sealed state is provided on the outer side of the predetermined sealed space, high temperature heat from the exhaust gas is prevented from propagating to the outside of the silencer. That is, the heat shield effect is enhanced.

Next, the invention according to claim 2 will be described. This one is also the same as the one described in claim 1 in the basic point. The feature is that it relates to the ring-shaped sound deadening member. That is, in the present invention, in the sound deadening device according to claim 1, the sound deadening member is based on a braided body formed of thin metal wires having a predetermined diameter, and the braided body mainly comprises buckling forming means. It is decided to adopt a configuration in which the above-mentioned predetermined forming means is composed of a member formed to have a ring-like shape having a predetermined width. By adopting such a configuration, in the present invention, it is possible to form (manufacture) the sound deadening member having innumerable predetermined minute gaps relatively inexpensively. In addition, such a sound deadening member has a predetermined sound deadening function, and by installing an appropriate number of such single parts, it becomes possible to adapt them to respective sound deadening devices, and (Members) can be shared. That is, it becomes possible to make the silencer member a common product or a standard product.

Next, the invention according to claim 3 will be described. Also in this case, the basic points are the same as those described in claim 1 or claim 2. That is, in the present invention, in the sound deadening device according to claim 1, the sound deadening member is based on a myriad of metallic fiber materials, and the aggregate is a predetermined molding means mainly composed of press molding means, It was decided to adopt a configuration of a member formed to have a ring shape having a predetermined width. By adopting such a configuration, in the present invention, it becomes possible to standardize the parts and standardize the same as in the above-mentioned claim 2, and in addition to these, the metal The sound deadening member can be formed of a metal fiber material (metal wool or the like) formed on the basis of a scrap material or the like, and the manufacturing cost of the sound deadening member can be reduced.

Next, the invention according to claim 4 will be described. This one is also the same as the one described in claim 1 in the basic point. That is, in the present invention, the sound deadening device according to claim 1 is configured such that the heat insulating layer is made of a ceramic fiber formed of a new ceramic material. By adopting such a configuration, in the present invention, it becomes possible to form the heat insulating layer with a new ceramic material such as alumina or silica. It is possible to reduce the weight of the silencer as a whole.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS. Although it relates to the present embodiment, its configuration is connected to an exhaust pipe as shown in FIG.
An inner cylinder 1 through which exhaust gas or the like flows, and is attached (fitted) to the outer peripheral portion of the inner cylinder 1 and has a ring-like shape formed to have a constant width. In addition, a sound deadening member 2 formed of a predetermined thin metal wire 21 or a metal fiber material, and a predetermined closed space 5 provided outside the sound deadening member 2 are formed. An inner shield 3 provided, a heat insulating layer 6 provided outside the inner shield 3 and having a predetermined thickness, and an outer cylinder 7 that holds the heat insulating layer 6 in a sealed state. It is basically composed of ,. In addition, in such a structure, a large number of small holes 11 are provided at the outer peripheral portion of the inner cylinder 1.

In such a structure, the sound deadening member 2 mounted (fitted) on the outer peripheral portion of the inner cylinder 1 where the small hole 11 is provided is basically as shown in FIG. Has a ring shape and has a predetermined width. Then, as shown in FIG. 1, a plurality of such ring-shaped sound deadening members 2 are installed in a state in which they are in close contact with each other in the axial direction of the inner cylinder 1,
As a result, a predetermined sound deadening layer is formed.

Next, an embodiment of a method of manufacturing the ring-shaped sound deadening member 2 having such a structure will be described with reference to FIG. First, a braided body 9 made of a tubular body as shown in FIG. 2A is formed by using a predetermined thin metal wire 21 having a diameter value of 1 mm or less, 0.25 mm in the present embodiment. . In this embodiment, the wire is made of stainless steel (SUS), or a metal thin wire such as a copper wire or an aluminum wire. Then, the thin metal wires 21 are braided into the braided body 9 made of a tubular body. Further, based on such a braided body 9, a predetermined buckling forming is performed by applying an axial load as shown by an arrow to the braided body 9 as a whole, as shown in FIG. A ring-shaped member is formed. That is, by applying a predetermined forming means mainly composed of the buckling press forming means, the sound deadening member 2 formed of a ring-shaped member having a predetermined width as shown in FIG. 2B is formed. At this time, the sound deadening member 2 has the thin metal wires 21 at a rate of about 2.4 grams per cubic centimeter. The density of the metal thin wires 21 can be appropriately adjusted, and the density and the like are changed (adjusted) depending on the sound (sound wave) to be silenced.
To be done.

Since the entire sound deadening member 2 thus formed (manufactured) is in a state in which the thin metal wires 21 are intertwined with each other, the gaps 29 are formed innumerably throughout the whole. There is something. Therefore, the sound (sound wave) flows through this gap 29, and at the time of this flow, the sound (sound wave) is attenuated (attenuated) by the contact or interference with the adjacent metal wire (fine wire) 21. Become. In addition, as for the ring-shaped sound deadening member 2, a metal fiber material aggregate such as metal wool is further used as a base, and a predetermined press molding means or the like is applied to the ring-shaped sound deadening member 2. A method of forming (manufacturing) the silencing member 2 made of a ring-shaped member as shown is also conceivable.

Then, the ring-shaped sound deadening member 2 as described above is used.
A closed space 5 having a predetermined capacity is formed outside the installed space, and an inner shield 3 made of a metal material such as stainless steel or titanium alloy is provided outside the closed space 5. Further, a heat insulating layer 6 made of ceramic wool (ceramic fiber) is provided on the outer side thereof. Further, at an outer side of the heat insulating layer 6 made of the ceramic wool, the heat insulating layer 6 made of the ceramic wool is held in a sealed state, and an outer cylinder made of a metal material such as titanium alloy or stainless steel. 7 is provided. As the ceramic wool (ceramic fiber) forming the heat insulating layer 6, in the present embodiment, alumina, silica, or a mixture thereof is adopted.

Next, the silencing action and the like of the present embodiment having such a configuration will be described. First, in FIG. 1, when a high-temperature exhaust gas flows into the inner cylinder 1 at a high speed, a part of the exhaust gas flows into the small hole 1
It flows via 1 to the muffling member 2 provided around it. Then, it further expands / diffuses to the minute gap 29 provided at the sound deadening member 2. By the way, the fine gaps 29 provided in the sound deadening member 2 are formed by the entanglement of the thin metal wires 21 forming the sound deadening member 2, and have a complicated shape. Therefore, the sound (sound wave) that has entered the fine gap 29 is
It will be attenuated by repeating reflection and interference within 9. That is, the sound wave (sound) of a specific frequency (especially high frequency range) is attenuated while passing through the sound deadening member 2 having such a minute gap 29.

Then, the sound wave (sound) passing through such a sound deadening member 2 advances to the inner shield 3 side through the sealed space 5 (see FIG. 1), and the inner shield 3 concerned.
The sound absorbing member 2 is reflected again at the inner wall 31 of the
It returns to the outer surface portion 22 of the. Then, some of them are re-reflected at the outer surface portion 22 and reflected to the closed space 5 side, and some of the rest of them enter into the fine gaps 29 of the silencing member 2, It will be attenuated here. The sound wave (sound) reflected at the outer surface portion 22 of the sound deadening member 2 is diffusely reflected at the outer surface portion 22 because the outer surface portion 22 has fine irregularities. It will return to the closed space 5. Such irregular reflection causes the outer surface portion 2 of the sound deadening member 2 to
The sound wave (sound) that has passed through the sound deadening member 2 is finally attenuated (damped) by being repeatedly performed between the sound absorbing member 2 and the inner wall 31 of the inner shield 3. That is, in the case of the present embodiment, most sound waves (sounds) in the frequency band are absorbed and silenced at the silencer. Further, the heat dissipated at the sound deadening member 2 and the closed space 5 is cut off at the heat insulating layer 6 and is not radiated to the outside of the sound deadening device.

[0016]

According to the present invention, in regard to a silencer for reducing exhaust noise, an exhaust gas is introduced and an inner cylinder having a large number of small holes in its outer periphery and a myriad of fine metal wires. And a sound deadening member formed in a ring shape having a predetermined width by a predetermined molding means, and the ring sound deadening member is A plurality of the inner cylinders and the ring-shaped sound deadening member are arranged in parallel at the outer peripheral portion of the cylinder having the small holes so as to be in close contact with each other in the axial direction. Where a predetermined closed space is provided, and further, a heat insulating layer having a predetermined thickness and made of a predetermined heat insulating material is provided outside the closed space, and the heat insulating layer is kept in a sealed state. A structure that provides a cylinder Since it was decided to take it, it is said that when the exhaust gas flows in the inner cylinder at a high speed, the sound absorbing material such as glass wool is sucked out and discharged to the outside of the silencer, that is, to the outside. No more inconvenience occurred. Further, instead of the sound absorbing material such as glass wool, the heat insulating material made of ceramic wool (ceramic fiber) is provided on the outside of the silencer, so that the weight of the silencer as a whole can be reduced. Further, it becomes possible to form a sound deadening layer by fitting (attaching) a sound deadening member having a predetermined ring shape to the outside of the inner cylinder, and this single sound deadening member can be used as a small hole in the inner cylinder. By installing an appropriate number in the place where is provided, it has become possible to contribute to the silencing of the target sound range (frequency). That is, in the present invention, it is possible to achieve the sound deadening effect of sounds in various sound ranges (frequency) by installing an appropriate number of sound deadening members, and thereby the characteristics of the sound deadening device can be freely set. You can now tune.

Further, in the present invention, the silencing member is based on a braided body formed of thin metal wires having a predetermined diameter, and the braided body is a predetermined forming means mainly composed of buckling forming means. In this case, since it is decided to adopt a configuration of a member formed to have a ring shape having a predetermined width, it is possible to relatively inexpensively form a sound deadening member having an infinite number of predetermined fine gaps. It became possible to (manufacture). Further, such a sound deadening member has a predetermined sound deadening function by itself, and by appropriately installing a plurality of such single parts, different sound deadening functions can be achieved. As a result, it has become possible to share parts (silencer members). In other words, it has become possible to make the muffling member a common product or a standard product.

Further, the sound deadening member has a ring-like form having a predetermined width by a predetermined forming means mainly composed of press forming means based on a myriad of metallic fiber materials. In the case of adopting the configuration of the member formed as described above, the sound deadening member can be formed by the metal fiber material (metal wool etc.) formed on the basis of the metal end material etc. As a result, it is possible to reduce the manufacturing cost of the sound deadening member.

[Brief description of drawings]

FIG. 1 is a half sectional view and an external view showing the overall configuration of the present invention.

FIG. 2 is a diagram showing a manufacturing process of a sound deadening member forming a main part of the present invention.

FIG. 3 is a perspective view showing an overall configuration of a conventional example.

[Explanation of symbols]

1 inner cylinder 11 small holes 2 silencer 21 Metal thin wire (metal fiber) 22 Outer surface 29 Gap (fine gap) 3 Inner shield 31 inner wall 5 closed space 6 heat insulation layer 7 outer cylinder 9 braid

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-4-36013 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F01N 1/04 F01N 1/02 F01N 7 / 08 F01N 7/14

Claims (4)

(57) [Claims] 1. An inner cylinder, into which exhaust gas is introduced, which has a large number of small holes in its outer peripheral portion, and an aggregate of innumerable thin metal wires, which are formed on a predetermined basis. A sound deadening member formed in a ring-like shape having a predetermined width by a molding means, and the ring-shaped sound deadening member at the outer peripheral portion of the inner cylinder having the small hole, A plurality of them are arranged in parallel in a state of being closely attached to each other in the axial direction, and a predetermined sealed space is provided at the outer peripheral portion of the inner cylinder and the ring-shaped sound deadening member, and further outside of the sealed space. A sound deadening device comprising a heat insulating layer having a predetermined thickness and made of a predetermined heat insulating material, and an outer cylinder for holding the heat insulating layer in a sealed state. 2. The sound deadening device according to claim 1, wherein the sound deadening member is based on a braided body formed of a thin metal wire having a predetermined diameter, and the braided body mainly comprises buckling forming means. A silencer characterized by comprising a member formed to have a ring shape having a predetermined width by a predetermined molding means. 3. The sound deadening device according to claim 1, wherein the sound deadening member is made of a predetermined number of metal fibers based on a predetermined molding means mainly composed of press molding means. A silencer comprising a member formed to have a ring-like shape having a width. 4. The silencer according to claim 1, wherein the heat insulating layer is made of a ceramic fiber made of a new ceramic material.