JPS58104318A - Adiabatic exhaust pipe - Google Patents

Abstract

PURPOSE:To improve adiabatic property, sound insulating property and durability of an exhaust pipe of an engine by using specified ceramics respectively for portions subjected to shock and the remaining portions as adiabatic material of adiabatic layer in adiabatic exhaust pipes provided therearound with the adiabatic layer. CONSTITUTION:A front exhaust pipe 3 of an automobile engine for example has internal exhaust pipes 31, 32 extending therethrough and an outer tube 6 fitted thereon at predetermined intervals. And the outer tube 6 consists of the upper and lower outer tube 61, 62, both ends of the lower outer tube 62 being caulked at both ends of the upper outer tube 61. An adiabatic material 7 of ceramic fiber is filled in the lower half of the exhaust pipe receiving shock of flying pebbles and an adiabatic material 8 of foamed ceramic is filled in the upper residual half respectively between said exhaust pipes 31, 32 and the outer tube 6. Thus, the outer tube 6 is contacted fully with both adiabatic materials 7, 8 by foaming pressure of the adiabatic material 8 to restrain vibration and reduced noise while obtaining satisfactory adiabatic effect.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an insulated exhaust pipe that provides heat insulation around the exhaust pipe of an engine, and particularly relates to an insulated exhaust pipe that reduces vibrations and noise caused by an outer cylinder that violates heat insulation.

The exhaust system of an engine used in an automobile or the like becomes a high-temperature heat source for exhaust gas purification, and becomes cloudy. The exhaust pipe that breaks from the exhaust manifold to the catalytic converter also
This is one of the heat sources, and in order to reduce the heat effect on surrounding parts, etc., an outer cylinder is installed around the exhaust pipe of the building, and a heat insulating material is filled between the exhaust pipe and the outer cylinder to create an RRS layer. An insulated exhaust pipe is used. Gaff fibers, Vrica fibers, Cefmic fibers, etc. have been used as the rounded heat insulating material. However, in this case, although a heat-insulating result is obtained, the outer cylinder receives vibrations from the engine, causing the fR to fluctuate and emit a loud rattling noise, which is a cause of worsening the noise inside and outside the vehicle. It has also been devised to fill this rounded V# with porous ceramics such as foamed ceramics as a heat material.
If the outer cylinder located on the lower side of C'II+ is damaged by a blow from a flying stone, etc., the insulation material will be damaged and the cylinder will gradually fall and disappear, which will not only reduce the cutting performance but also increase the vibration and noise. there were.

The present invention aims to solve one of the above problems and provide an insulated exhaust pipe with excellent heat insulation and soundproofing properties as well as sufficient fire resistance.

Hereinafter, this invention will be explained in detail according to embodiments shown in the drawings. FIG. 1 is an exploded explanatory diagram showing the arrangement of the exhaust threads of the engine of my car, including engine 1, exhaust manifold 2,
Front exhaust fi'f5. [Contains converter 4, center exhaust q12, muffler 5, front exhaust pipe 5]
is an insulated exhaust pipe.

Figure 2 shows a practical example of the first invention.
This is the composition a diagram of 5, and inside the front wandering%tt5 there is #
The # palanquins 31 and 32 are fitted through each other, and an outer cylinder 6 is provided at a substantially constant interval therebetween as shown in FIG. The outer end 6 consists of an upper outer hook 61 that almost surrounds the upper surface of the protrusion 131.52, and a lower outer end 62 that almost encloses the lower part of the rod, and both ends of the lower outer cylinder 62 are connected to both ends of the upper outer cylinder 61. It is crimped and integrated into ti and r. Between the exhaust pipes 31 and 32 and the outer end 6, there is a heat insulating material 7 made of Cefmiter II in the lower half that receives impact from flying stones, etc., and a heat insulating material 7 made of Cefmiter II in the remaining upper half. A heat insulating material 8 is filled. The heat-resistant material 8b made of this foamed Cefmic is a round material made by kneading four types of ceramic powder with sodium silicate and gold beak aluminum. The filling method of .8 is to place the heat insulating material 7, which has been vacuum formed in advance and consists of nine ceramic ruts, on top of the lower outer Wi 62.The bond exhaust pipes 51 and 52 are fixed in a predetermined position, and then the lower outer end 6 is placed.
1 and caulk it to the lower outer Wi 162. After stirring, a foamed ceramic material having the above-mentioned composition is poured between the exhaust Xf 31, 32 and the upper outer cylinder 61 and allowed to stand overnight at room temperature to foam.

According to the above actual example, outside the front exhaust pipe 3 11@6
is a heat insulating material made of foamed Cefmic with a foaming pressure of 80%.
Make sufficient contact with heating material Otsu 8. As a result, the following motion is suppressed, which reduces perspiration. Also, the heat insulating material 7 made of Mitsuta fiber is used in the parts that can receive impact from stones etc. during the first run, so #? - The front exhaust pipe 5 is not damaged, and therefore the heat insulation properties and noise characteristics of the front exhaust pipe 5 are not deteriorated. Furthermore, as the filling method for the heat insulating material 8 made of foamed ceramic, the foaming process is performed after filling the material in the form of a cotton wool material, so that the filling process can be performed reliably and at low cost.

@Figure 4 is a sectional view taken at the same position as the line A in Figure 2, showing the second example of real power. In this second embodiment, the front exhaust f5 rises along the cylinder block (not shown) of the engine toward the exhaust manifold (not shown).
1 (Fig. 42-A line)), only the heat material 9 made of foamed ceramic is used to support the heat insulation layer of the front exhaust R5 on the 41st part, and the other parts are 41★ suitable. This book has the same wr heat material configuration as the example (Figure 3).

Even if you do this, the front exhaust/g! Since the part above the JL- line in 1 is not hit by flying moons, etc., the F side of the heat-resistant material 9 made of foamed ceramic is destroyed. We have confirmed that similar effects can be obtained.

FIG. 5 shows a front wandering Xf5 according to the second invention,
As shown by the dotted lines in the figure, the outer cylinder 6 is divided into approximately five equal parts in the longitudinal direction, and is filled with metal wire mesh V110 (my father is 11) with a width of several 1 as an Ifr heat material. In the part shown in FIG. 3, the heat insulating material structure is the same as that of the first practical example according to the first invention (FIG. 3). FIG. 6 is a cross-sectional view taken along the line B-B in FIG. 5, which shows the first practical example. It is filled. Figure 7 is the second 4! This figure is similar to FIG. 6 showing a definite example, and in this case only the lower half of the space is filled with metal wire mesh 11. In either case, the first aspect of the first invention,
Equivalent to the second practical example - heat resistance is obtained, but as for sweat resistance, the elastic repulsion force of Gold 14 wire mesh S', 10.11 acts on the outer cylinder, so the result is more soaked. I acknowledge that I can get it.

In all of the above cases, the foamed ceramic insulation materials 8 and 9 were filled with souffle-like material and foamed at room temperature.
/um mixture was recently heated and then heated at 700℃ for 5 minutes.
It may be heated and foamed for 0 minutes, and the same results can be obtained in this case as well.

As described in detail above, according to the present invention, sufficient f
# It is possible to easily manufacture an insulated exhaust pipe that has heat resistance, excellent soundproofing properties, and does not deteriorate in performance even when subjected to impact from flying stones.

[Brief explanation of drawings]

Figure 1 is an expanded explanatory diagram showing the arrangement of the exhaust system of the engine of an automatic umbrella, Figure 2 is a diagram of the front exhaust pipe according to the first embodiment of the first invention, and Figure @5 is # fI2mA-Ad new surface view, Figure 4 is the same as Figure 2 Mu A line showing the second embodiment -1
Figure 45 is a cross-sectional view of the front exhaust system according to the second invention.
Fig. 46 is a 4Na diagram of g, and Fig. 46 is a mountain view taken along the line B-E in Fig. 5 w#, which corresponds to the first embodiment, and Fig. 47 is a similar sectional view showing the second embodiment. 5...Front exhaust pipe 6...External 7...Ceramic 41 material made of 8.9...
Insulating material made of foamed ceramic 10.11...Metal wire 7V. Representative of Toyota Motor Corporation Patent attorney Oka 1) Hidehiko 1st v! J Figure 2 1 Figure 3 Figure 4 Figure 5 'OIf j111711

Claims (2)

[Claims] (1) A heat insulating material is filled between the exhaust pipe of the engine and an outer cylinder that surrounds the outer circumference of the exhaust pipe with a space between them.
! ? ! In the heat insulating exhaust 1'Cf having a layer, the section #-
9. An insulated exhaust system characterized in that, as a heat insulating material, a deformable material made of Cefmic Ill cloth is filled in the part exposed to impact from a walking stone, etc., and a heat insulating material made of porous Cefmic is filled in the remaining part. tube. (2) In an insulated exhaust pipe having a heat layer filled with Wtr thermal material between an engine exhaust pipe and an outer cylinder surrounding the outer periphery of the exhaust pipe with a space therebetween,
As the ll material, Kinkyo Firemets VjL was used at one or more locations in the axial direction of the exhaust pipe, and heat insulating material made of Cefmic fiber was used at other locations that would receive impact from blasphemous stones, etc. An insulated exhaust pipe characterized in that the part is filled with an I# thermal material made of porous cefmic.