JPH0783913B2 - Wire mesh porous body for engine muffler and method of manufacturing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a wire mesh porous body for an engine muffler mainly used for reducing muffler noise of a general-purpose engine, and a method for manufacturing the same.

[Conventional technology]

Conventionally, in order to reduce the muffler sound of a general-purpose engine,
As shown in FIG. 3, means for holding and mounting the metal foam 3 at the outlet 2 of the muffler body 1 with the mounting cover 4 is adopted. In another embodiment, as disclosed in Japanese Utility Model Laid-Open No. 62-18323, a means for attaching one baffle (wire net) to the outlet of the muffler tail pipe is adopted.

[Problems to be Solved by the Invention]

By the way, in the former method, the cost of the metal foam 3 is high, and the shock resistance to the engine vibration, gas pressure and the like is poor, so that the mounting method is limited.

The latter means cannot obtain a sufficient silencing effect because it is thin.

The muffler noise is reduced by reducing the porosity of the porous body, but if it is too low, the exhaust pressure rises and the engine performance deteriorates. Therefore, the engine performance is not sacrificed, that is, in order to secure a sufficient silencing performance with a high porosity, it is necessary to increase the thickness to form a three-dimensional mesh. However, a sufficient three-dimensional mesh cannot be obtained by simply overlapping the wire meshes, and the rigidity of the wire meshes is poor. Therefore, there is a risk that the wire meshes will fall off by the mounting method shown in FIG. Therefore, it was necessary to fix the wire mesh to the cover 4 by some method.

Therefore, the present invention is to provide a wire mesh porous body for a muffler of an engine, which has a sound deadening performance equal to or higher than that of the metal foam, and is excellent in impact resistance and rigidity, and a method for producing the same. .

[Means for Solving the Problems]

The metal mesh porous for muffler of the engine of the present invention for solving the above-mentioned problems, one flat knitted wire mesh is stacked and compressed, and the wire rods of each knitted wire mesh are randomly entangled in a three-dimensional direction. It is formed by forming minute gaps which are communicated with each other uniformly.

The manufacturing method according to the present invention for producing a wire mesh porous body for a muffler of this engine corrugates one flat knitted wire mesh, and then several corrugated metal meshes are crossed in the direction of the waves to produce a heavy weight. It is characterized in that the corrugated metal nets are stacked and then press-molded to have a certain thickness, and then punched into a desired shape.

[Action]

The metal mesh porous body for the muffler of the engine of the present invention having the above-described structure has minute gaps which are communicated in the three-dimensional direction uniformly formed, and has a high porosity, so that the muffling effect is sufficient when attached to the muffler outlet. Is obtained. In addition, since the wire material of the knitted wire mesh is intertwined at random, it has elasticity and can sufficiently withstand shocks such as engine vibration and gas pressure. Furthermore, since it has sufficient rigidity, it can be firmly attached to the muffler outlet and can be prevented from falling off.

Further, according to the method for manufacturing a wire mesh porous body for a muffler of an engine of the present invention, not only a wire mesh porous body having the above-described effects can be easily obtained at a low cost, but also a wire mesh wire. Since the porosity can be arbitrarily selected and changed by appropriately changing the diameter, the number of wires, the knitting stitch size, the corrugated size, the number of layers, the press thickness, etc., a wire mesh porous body according to various usage modes can be obtained. Obtainable. Moreover, since the material of the knitted wire mesh can be freely selected, it is possible to obtain a wire mesh porous body which can be applied to applications other than muffler noise reduction.

〔Example〕

An embodiment of a wire mesh porous body for a muffler of an engine and a method for manufacturing the same according to the present invention will be described. First, the manufacturing method will be described. For example, the wire diameter is 0.35 mm and the number of wires is 1 as shown in FIG.
One flat rectangular knitted wire mesh 10 made of SUS304 of 60 to 70 pieces per square inch of stitch size per square inch is approximately 5 m in the direction perpendicular to the knitting line direction as shown in FIG. 1 (b).
Corrugation with a height of about 2.5 mm at m pitch. Next, several corrugated wire nets 11 (in this example, five corrugated wire nets 11) are crossed in the direction of the waves and stacked as shown in FIG. 1 (c). Next, the corrugated wire nets 11 thus stacked are press-molded to form a wire mesh porous body 12 having a thickness of about 8 mm as shown in FIG. 1 (d). After that, a desired shape is formed according to the application, in this example, as shown in FIG. 1 (e), it is punched out into a circular shape having a diameter of about 35 mm and molded.

In the metal mesh porous body 12 'manufactured in this manner, five knitted wire meshes 10 are stacked and compressed, and the wire rods 10' of each knitted wire mesh 10 are randomly entangled as shown in FIG. The minute gaps 13 communicating in the three-dimensional direction are uniformly dispersed and formed. Therefore, this wire mesh porous body 12 '
Has a high porosity of about 90%, the metal foam 3 of FIG.
Similarly to the muffler body 1, the wire mesh porous body 12 'is provided at the outlet 2 of the muffler body 1.
When the cover is held by the cover 4 and attached, a sufficient noise reduction effect can be obtained. Further, since the wire rods 10 'of the knitted wire mesh 10 are intertwined with each other at random, the knitted wire mesh 10 has elasticity and can sufficiently withstand impacts such as engine vibration and gas pressure. Further, as described above, the wire rods 10 'of the knitted wire mesh 10 are randomly intertwined with each other so that the wire meshes 10 are reinforced and integrated with each other and have sufficient rigidity, so that the muffler body 1 can be firmly attached to the outlet 2. , Can be prevented from falling off.

In the method for producing a metal mesh porous body for a muffler of an engine of the present invention, the wire diameter, the number of wires, the knitting stitch size, the corrugated size, the number of stacks, the press thickness, etc. of the knitted wire mesh 10 can be appropriately selected and changed. For example, since the porosity can be arbitrarily changed, it is possible to obtain a wire mesh porous body according to various usage modes. Further, since the material of the knitted wire mesh 10 can be freely selected, it is possible to obtain the wire mesh porous body which can be applied to applications other than the muffler noise reduction.

〔The invention's effect〕

As described above, since the metal mesh porous body for a muffler of the present invention has a high porosity, a sufficient silencing effect can be obtained for muffler noise reduction. Further, since it has elasticity, it can sufficiently withstand shocks such as engine vibration and gas pressure. Furthermore, since it has sufficient rigidity, it can be firmly attached and will not fall off.

Further, according to the method for producing a wire mesh porous body for a muffler of an engine of the present invention, the above excellent wire mesh porous body can be easily obtained at low cost, and further, the specifications of the knitted wire mesh and the number of overlapping layers. By appropriately selecting and changing the press thickness and the like, the porosity can be arbitrarily changed, and a wire mesh porous body can be obtained according to various usage modes. In addition, since the material of the knitted wire mesh can be freely selected, it is possible to obtain a wire mesh porous body which can be applied to applications other than muffler noise reduction.

[Brief description of drawings]

1 (a) to (e) are diagrams showing steps of the method for producing a wire mesh porous body of the present invention, and FIG. 2 is a cross-sectional view of the wire mesh porous body for a muffler of the engine of the present invention. The figure is a diagram showing a state in which a conventional metal foam is provided at the outlet of the muffler body for reducing the muffler sound. 10 ... Knitted wire mesh, 10 '... Wire material 11 ... Corrugated wire mesh, 12, 12' ... Wire mesh porous body 13 ... Gap

Front page continuation (72) Inventor Tetsuaki Shirai 1-1 Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries, Ltd. Akashi factory (56) References Japanese Patent Publication Sho 55-21172 (JP, B2)

Claims (2)

[Claims] 1. A flat knitted wire mesh is corrugated, and the directions of the corrugations are crossed and several sheets are stacked and compressed.
A wire mesh porous body for an engine muffler, in which wire rods of each knitted wire mesh are randomly entangled and three-dimensionally communicating minute gaps are uniformly dispersed. 2. A flat knitted wire mesh is corrugated, then several corrugated metal meshes are stacked by crossing the directions of the waves, and then this stacked corrugated metal mesh is pressed. A method for producing a wire mesh porous body for a muffler of an engine, characterized in that it is formed into a certain thickness and then punched into a desired shape.