JPS6022017A - Exhaust gas cleaning device of motor cycle - Google Patents

Abstract

PURPOSE:To enable to absorb the dimension error of a monolithic supporting body by a method wherein the holding part of the monolithic supporting body of an exhaust gas expanding part is divided in lengthwise direction of the supporting body, then both sides of the monolithic are body supported with said divided bodies, in the tittle device which contains the monolithic catalytic substance in the exhaust gas expanding part. CONSTITUTION:An exhaust gas cleaning device of a four-cylinder motorcycle is provided with four connecting joints 28a-28d to which exhaust pipes communicated to each cylinder are fitted at the front surface side in running direction, further, includes an exhaust gas chamber 17 having a pair of joint pipes 32 connected to left and right mufflers at the rear surface side thereof. The exhaust gas chamber 17 is formed by overlapping up and down direction with an upper and lower divided bodies 18, 19 made of metal plate, a monolithic catalytic substance 35 is contained in the chamber 17 via a supporting member 40. Opening parts 41 are formed through both upper and lower surfaces of the exhaust chamber 17 on the prearranged part 36 for holding of the catalytic substance 35 at both left and right sides of the exhaust chamber 17. Each opening part 41 is made to be covered with nearly U-shaped press plate 42 as a divided body forming a part of the chamber 17.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust purification device for a motorcycle in which a monolithic catalyst is housed in an exhaust expansion section provided between an exhaust pipe and a muffler.

For example, when installing a monolithic catalyst for exhaust purification in a motorcycle equipped with a multi-cylinder engine, it is well known that the monolithic catalyst is installed inside an exhaust chamber where the exhaust pipes led out from each cylinder are gathered together under the crankcase. It is being This monolithic catalyst has catalyst components supported on a monolithic carrier having an integral structure.This monolithic carrier is formed into a flat shape that matches the cross-sectional shape of the exhaust chamber, and its outer periphery is It is housed and held within the exhaust chamber by being brought into close contact with the inner circumferential surface of the exhaust chamber.

By the way, as is already known, monolithic carriers are
Since it is a fired product made by firing and hardening an integral ff'J structure made of cordierite, etc., its dimensions tend to vary due to the thermal influence, and especially when it is formed into a flat shape as described above, the dimensional error in the longitudinal direction is more than in the thickness direction. becomes larger. However, the current exhaust chamber has a two-part design in which the upper and lower parts made of sheet metal are overlapped from above and below, so it is impossible to absorb the dimensional error in the longitudinal direction of the monolith carrier. Become. Therefore, if the monolithic carrier is too long, it will be impossible to overlap both segments;
Also, if it is too short, a large gap will open between it and the inner peripheral surface of the exhaust chamber, and the exhaust gas will naturally blow through.
There is a problem where the monolith carrier shakes.

If such rattling occurs, the monolith carrier is a fired product and is easily broken, so there is a risk of damage due to street strikes.

The present invention was made based on these circumstances, and
dimensional errors in the longitudinal direction of the monolithic carrier can be easily absorbed,
The purpose is to securely and firmly hold the monolithic carrier within the exhaust expansion section to prevent damage to the monolithic catalyst.

That is, in order to achieve the above object, the present invention divides at least the portion of the exhaust expansion section in which the monolithic carrier is accommodated in the longitudinal direction of the monolithic carrier, and the boundary line with the divided body is set on both sides of the monolithic carrier in the thickness direction. The divided bodies are placed on the upper and lower surfaces and in a direction that intersects with the longitudinal direction of the monolithic carrier, and the divided bodies are applied from both sides of the monolithic carrier in the longitudinal direction, and the overlapping amount on the boundary line is set to the monolithic carrier. It is characterized by being welded in a state adjusted according to the longitudinal dimension of.

A first embodiment of the present invention will be described below with reference to FIGS. 1 to 7.

1 in Figure 1 is a cradle-shaped 74 Innoframe,
A front fork 4 that supports a front wheel 3 is pivotally supported on the head pizo 2 of this frame 1, and a 4-stroke, 4-cylinder engine 8 is mounted in a portion surrounded by a tank rail 5, a down tube 6, and a seat pillar tube 7. Mounted. Further, a rear pXJ-m 10 is pivotally supported on a bracket 9 welded to the lower end of the seat pillar tube 7, and this rear pXJ-m 1.
A chain-driven rear wheel 11 is supported at the rear end. In addition, 12 in FIG. 1 indicates a fuel tank, and 13 indicates a seat.

Exhaust pipes 15th' to 15d are connected to the air volumes Q14a to 14d of the engine 8, respectively.

These exhaust pipes 15a to 15d are led out in parallel to the lower side of the crankcase 16 of the engine 8, and their respective lead-out ends are connected to the exhaust nayanba 12 as an exhaust expansion section directly below the crankcase 16. There is. As shown in FIGS. 2 to 5, the exhaust chamber 17 is constructed by overlapping an upper divided body 18 and a lower divided body 19 made of sheet metal from above and below, and is shaped like a horizontally flat hollow box. is formed. The upper divided body 18 and the lower divided body 19 integrally have rising walls 22 and 23 that are continuous in the circumferential direction at the outer peripheral edge of the flat base parts 20 and 21, and the raised walls 22 of the upper divided body 18 A fitting portion 24 that bulges outward is formed at the tip. And this fitting part 24
The tip of the rising wall 24 of the lower divided body 19 is fitted inside and welded over the entire circumference, thereby creating a flat cross section in the left and right direction between the two divided bodies 18 and 19. An exhaust expansion chamber 25 is formed. On the front part 26 of the rising wall 22, 23, there are four exhaust ports 2.
7a to 27d are formed, and these exhaust inlets 27a
~, connection joints 28a~28 installed in 27d
The outlet ends of the exhaust pipes 15a to 15d are fitted into the exhaust pipes 15a to 15d, and are kept tightened by a tightening band 29, respectively. A pair of exhaust outlets 31.31 are formed on the rear surface 30 of the rising wall 22.23, spaced apart from each other on the left and right, and joint pipes 32.31 are connected to these exhaust outlets 31.31.
Left and right silencers 33 and 33 are respectively connected to 32, and are kept tightened by a tightening band 29. Therefore, the exhaust from the air volume W'N14th to 14d is the exhaust pipe 1.
5a to 15d into the exhaust expansion chamber 25, where it is once collected, distributed to the exhaust outlet 31.31, and exhausted to the outside through the left and right silencers 33.33.

Reference numeral 34.34 denotes a protector that hides the area from the left and right sides of the exhaust chamber 17 to the connecting portion of the muffler 33.33 from the side.

A monolithic catalyst 35 for purifying exhaust gas is housed in the exhaust chamber 17 having such a configuration. This monolithic catalyst 35 has an exhaust population 27a to 27d and an exhaust outlet 3.
1.31, so as to cross in the left-right direction, and divide the exhaust expansion chamber 25 into front and rear sections with a constant width. The monolithic catalyst 35 is the sixth
As shown in the figure, a monolith carrier 37 is formed by baking and hardening a honeycomb-shaped integral structure made of cordierite, for example.
and a layer 38 impregnated with an active ingredient such as a noble metal having a catalytic action, which is adhered to this monolithic carrier 37, and the monolithic carrier 37 has a large number of through holes 39 along the flow direction of the exhaust gas. The monolithic carrier 3″7 is connected to the exhaust expansion chamber 2.
5, and its outer peripheral portion is held by the exhaust chamber 17, that is, the inner surfaces of the upper divided body 18 and the lower divided body 19. That is, a holding member 40 is attached to the entire outer circumference of the monolithic carrier 37 to fill the gap between the outer circumferential surface and the inner surface of the exhaust chamber 17 and to hold the monolithic carrier 37 within the exhaust chamber 17. A heat-expandable ceramic material called Intalummat (trade name) is used as the holding material 40, and when exhaust heat is applied to this material, the heat-expandable material such as verculite expands and compresses into the gap. The monolith carrier 37 is inserted into the exhaust chamber 17
It is designed to be positioned and held inside.

On the other hand, as shown in FIGS. 3 and 7, there are two openings on the left and right sides of the exhaust chamber 17, which are located above the holding portion 36 and continuously open toward the upper and lower surfaces of the exhaust chamber 17. Section 41.41 is cut out.

These openings 41 , 41 are provided correspondingly to both longitudinally spaced ends of the monolithic carrier 37 , and the opening end edges of the upper and lower openings are formed on the monolithic carrier 37 .
It is located on the upper and lower surfaces of 7, intersecting with its longitudinal direction. And in the opening 41.41 there is an exhaust chamber 11.
Presser plates 42, 42 are attached from both sides. The holding plates 42, 42 are press-molded metal plates, and are provided with top plates covering the top openings of the openings 41.41, respectively, on the upper and lower edges of the side plate portion 43 that nails the side openings of the openings 41.41. Part 4
4 and a bottom plate portion 45 that covers the lower opening.

Such a holding plate 42.42 is applied so as to crowd the openings 41.41 from both sides along the longitudinal direction of the monolithic carrier 37, with the monolithic carrier 37 positioned in the holding portion 36 in the exhaust chamber 17. It is becoming more and more popular. The tip edges of the top plate part 44 and the bottom plate part 45 of the presser plates 42, 42 overlap the opening end edges of the upper surface opening and the lower surface opening from the outside, and form a boundary line xl-xl between the opening end edges of the upper surface opening and the lower surface opening. The boundary line X1-X is located on the upper and lower surfaces of the monolithic carrier 37 to intersect with the crystal. At this time, the overlapping length l of the top plate part 44 and the bottom plate part 45 on the boundary line xl-xl is adjusted according to the longitudinal dimension of the monolithic carrier 37. The presser plate 41.4 has its periphery welded to the opening periphery of the UIJ opening 41.41 over the entire circumference when the overlapping length l is adjusted. Therefore, the exhaust chamber 17 of this embodiment is divided in the longitudinal direction of the monolith carrier 37 only at the portion 36 where the monolith catalyst 35 is scheduled to be held, and the holding plates 42 and 42 form part of the peripheral wall of the exhaust chamber 17. It constitutes a divided body.

According to such a configuration, if the overlapping length l of the top plate part 44 and bottom plate part 45 of the presser plates 41 and 41 on the burial boundary line Xl'-Xl is adjusted according to the size of the monolithic carrier 37, This dimensional error in the longitudinal direction of the monolithic carrier 37 can be easily absorbed, and therefore the monolithic carrier 37 can be reliably fixed within the exhaust chamber 17. Moreover, since there is no gap between large 1 (ζ) on both sides of the monolith carrier 17 in the longitudinal direction, the easily breakable monolith carrier 17 does not rattle and damage can be prevented. Since the gap between the inner surface and the inner surface can be adjusted to the optimum value for the holding function of the retaining material 40, the retaining material 40 is densely packed between the monolith carrier 37 and the exhaust chamber 17 along the outer periphery, and the monolith carrier 37 can be held more reliably, and
This has the advantage of preventing exhaust gas from blowing through.

Note that the present invention is not limited to the first embodiment described above, and FIG. 8 shows a second embodiment in which the entire exhaust chamber 51 is divided into three parts. This exhaust chamber 51 consists of an upper half 52, a lower half 53 and one half 54 made of sheet metal, each of which has a flat base 55. It has rising walls 57 and 58 on the outer peripheral edge except for one side of 56. Further, the − side half body 54 includes a top plate portion 6o and a bottom plate which are superimposed on one side of the base portions 55 and 56 of the upper half body 52 and the lower half body 53 at the upper and lower edges of the side plate portion 59 along the vertical direction. It has a section 61. Therefore, this exhaust chamber 51 is formed by welding the rising walls 57', 57' of the upper half body 52 and the lower half body 53 against each other to form a product 62 with an open side on the negative side.
With the monolith carrier 37 accommodated in the product 62, one side half body 54 is applied from one end of the monolith pusher 37 in the longitudinal direction so as to cover one side opening of the product 62, and the top plate thereof is The rear end portions of the portion 60 and the bottom plate portion 6) are overlapped and welded to the base portion 55, 56, thereby forming a hollow flat shape. At this time, dimensional errors in the monolithic carrier 37 are absorbed by adjusting the overlapping length l of the top plate part 60 and the bottom plate part 61 according to the dimensions of the monolithic carrier 37.

Further, FIG. 9 shows a third embodiment in which the entire exhaust chamber 7 is divided into left and right halves.

This exhaust chamber 7 is made up of a left half body 72 and a half body 73 made of sheet metal, which are butted against each other from the left and right, that is, from the longitudinal direction of the monolithic carrier 37.
．． Top plate parts 76 and 77 overlapped with each other on the upper and lower edges of 75.
and bottom plate portions 78 and 79 are integrally formed. Therefore, the exhaust chamber 71 is arranged such that the top plate 76, 77, bottom plate 78, 79 and side plate 74, 75 of the left half body 72 and the right half body 73 are located approximately at the center along the longitudinal direction of the monolithic carrier 37. By overlapping and welding the parts, it is constructed into a hollow flat shape. At this time, depending on the dimensions of the monolith carrier 37, the top plate part 76,77, the bottom plate part 78, 79
By increasing or decreasing the overlapping length of the side plate portions 74 and 75, dimensional errors in the monolithic carrier 37 can be absorbed.

Further, FIG. 10 shows a fourth embodiment in which the entire exhaust chamber 81 is divided into four parts, vertically and horizontally. The exhaust chamber 8 in this embodiment is a left upper divided body 8 made of sheet metal.
2. The lower left divided body 83, the upper right divided body 84, and the lower right divided body 85 are butted against each other from both the thickness direction and the longitudinal direction of the monolith carrier 37, and one of the flat base parts 86 to 89, respectively. It integrally has rising walls 90 to 93 on the outer peripheral edge excluding the sides. Therefore, the exhaust chamber 81 is first divided into the upper left half body 82 and the lower left half body 83.
By abutting and welding the rising walls 90.91 and 92.93 of the upper right half body 84 and the lower right half body 85, a pair of products 94, 95 with openings on one opposing side are constructed. In this state, the openings of the products 94 and 95 are overlapped and welded at approximately the center along the longitudinal direction of the monolith carrier 37, thereby forming a hollow flat shape. At this time, dimensional errors in the monolithic carrier 37 are absorbed by adjusting the overlapping length l between the openings of the products 94 and 95 in accordance with the dimensions of the monolithic carrier 37.

Further, in each of the embodiments described above, the monolithic catalyst was arranged in the left and right direction in the exhaust chamber, but for example, as in the fifth embodiment shown in FIG.
d into one, and this collecting part 100 is connected to the exhaust chamber 1.
01 and one muffler 102 is connected to the other side of the rear end of the exhaust chamber 101, the monolithic catalyst 35 is connected to the front end and the side of the exhaust chamber 101. They may be placed along the same line.

Furthermore, it goes without saying that the number of engine f3 cylinders is not limited to four cylinders.

According to the present invention described in detail above, it is possible to easily absorb dimensional errors in the longitudinal direction of the monolith carrier, and as a result, the easily breakable monolith carrier can be securely fixed in the exhaust expansion section without wobbling, thereby preventing damage. It has the advantage of preventing

[Brief explanation of drawings]

1 to 7 show an f4'X1 embodiment of the present invention, FIG. 1 is a side view of the motorcycle, FIG. 2 is a plan view of the exhaust system, and FIG. 3 is a partial cross-section of the exhaust chamber. 4 is a sectional view taken along the line IV--IV in FIG. 3, FIG. 5 is a sectional view taken along the line V-V in FIG. 3, and FIG. 6 is a sectional view taken along the line V--V in FIG.
7 is an exploded perspective view, FIG. 8 is a sectional view showing the second embodiment of the present invention, FIG. 9 is a sectional view showing the third embodiment of the present invention, and FIG. 10 is an enlarged view of part I. FIG. 11 is a sectional view showing a fourth embodiment of the invention, and FIG. 11 is a partially sectional plan view showing a fifth embodiment of the invention. 8...Engine, 15a-15d...°exhaust pipe 117
．． 51, 71, 81, 101... Exhaust expansion part (exhaust chamber), 33... Exhaust pipe, 35... Monolith catalyst, 37... Monolith carrier, 42, 54°72, '
73, 82, 83, 84, 85... divided body (
presser plate, − side half-split body, left half-split body, right half-split body, left top split body, left bottom split body, right top split body, right bottom split body).

Claims (1)

[Claims] A hollow flat exhaust expansion section is provided between the exhaust pipe led out from the engine and a muffler connected to the exhaust pipe, and a catalyst component is supported on a flat monolithic carrier within the exhaust expansion section. In a motorcycle in which a monolithic catalyst is accommodated and the outer circumferential portion of the monolithic 4H body is held by the inner circumferential surface of the exhaust expansion section, at least the portion of the exhaust expansion section in which the monolithic carrier is accommodated is held by the monolithic carrier. It is divided in the longitudinal direction, and the boundary lines with the divided bodies are located on the upper and lower surfaces of both sides in the thickness direction of the monolithic carrier, and in a direction that intersects the longitudinal direction of this monolithic carrier, and this divided body is An exhaust gas purification device for a motorcycle, characterized in that the monolithic carrier is welded from both sides in the throwing direction, and the overlapping amount on the boundary line is adjusted in accordance with the longitudinal dimension of the monolithic carrier.