JP2952997B2 - Exhaust gas purification device - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention relates to an exhaust gas purification device attached to an engine of a motorcycle, for example.

(Prior Art) An exhaust gas purifying device for purifying exhaust gas by causing unburned components and harmful components contained in exhaust gas in a motorcycle 1 as shown in FIG. Used in exhaust systems. In the conventional exhaust gas purifying device, a catalyst is provided inside the muffler 2, and the exhaust gas is brought into contact with the catalyst to cause a catalytic reaction, and the reaction purifies the exhaust gas.

The muffler 2 of the motorcycle 1 has an exhaust pipe section 3 and a muffler section 4 in a form as shown in FIG. 10, and FIG. 11 shows an enlarged cross section taken along line AA of FIG. The catalyst-equipped plates 6, 6 which are curved in an arc shape are provided near the inner wall of the muffler body 5 as described above, and the plates 6, 6 are attached to the inner wall surface of the muffler body 5 with a gap of 1 to 5 mm, The exhaust gas flowing through the muffler 2 is configured to come into contact with the catalyst attached to the plate with catalyst 6. Reference numeral 7 in FIG. 7 denotes a silencer connected to the muffler unit 4 via an exhaust pipe 6.

(Problems to be solved by the invention) However, in the structure of the conventional exhaust gas purification device,
The catalyzed plates 6, 6 are provided in a cylindrical shape along the inner wall surface at a position close to the inner wall surface of the muffler body 5, so that the exhaust gas in contact with the catalyzed plates 6, 6 has a relatively high temperature around the pipeline. Therefore, it takes time before the catalytic reaction starts, the purification performance is reduced, and the temperature of the surface of the muffler body 5 is increased because the plates 6 and 6 with the catalyst are located close to the surface of the muffler body 5. As a result, it is necessary to take sufficient measures against heat damage on the surface of the muffler body 5, resulting in a problem that the cost is increased, the influence on the diffuser is large, and the output is easily reduced.

According to the present invention, a catalytic reaction can be positively performed with high-temperature exhaust gas, and the purification performance can be improved.
An object of the present invention is to provide an exhaust gas purifying apparatus capable of reducing heat damage of a muffler body and improving output of an engine.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above object, according to the invention of the exhaust gas purifying apparatus, in the exhaust gas purifying apparatus in which a catalyst-equipped plate is provided in a muffler constituting an exhaust system of an engine, Plates are installed in the muffler body along the longitudinal direction of the exhaust pipe section, and in both the inner body and the outer body at the center of the cross section of the muffler body, in the approximate diametric direction, and a plurality of catalyst-equipped plates are spaced from each other. It is arranged side by side with the exhaust pipe section.

(Function) Since the plate with the catalyst is installed in both the inner body and the outer body at the center of the cross section of the muffler body of the muffler body in the diameter direction, the high temperature part of the exhaust gas flowing through the muffler has a large surface area. , And the catalytic reaction is rapidly and positively started to enhance the purification performance. Further, since a large gap is formed between the plate with the catalyst and the inner wall surface of the muffler body, the temperature of the surface of the muffler body is suppressed from increasing. Further, the filling efficiency by the reflected wave is increased, and the output of the engine is improved.

(Embodiment) Hereinafter, an embodiment of an exhaust gas purifying apparatus according to the present invention will be described with reference to the accompanying drawings.

FIG. 2 shows a muffler 10 as an exhaust system of a motorcycle provided with an exhaust gas purifying apparatus according to the present invention. The muffler 10 has an exhaust pipe section 11 and a muffler section 12 connected to an engine exhaust port of a motorcycle. In the muffler section 12, a part of the exhaust pipe is greatly expanded to form an expansion chamber. An exhaust pipe 13 is connected to a downstream side of the muffler section 12, and a silencer 14 is connected to the exhaust pipe 13.

As shown in FIG. 1, the muffler 10 includes an inner body 15a provided on the vehicle body side and an outer body 1 provided on the outer side.
The muffler body 15 is formed by centering the muffler body 15 with 5b.

In this embodiment, the inner body 15a side and the outer body 1
A plate 16 with a catalyst is vertically fixed inside both the 5b side and the surface area of the catalyst layer is increased. The catalyst-equipped plates 16, 16 extend from the inner wall surface of the muffler body 15 on the inner body 15a side to the outer body 15b in the range of 1 / 3d to 2 / 3d of the inner diameter d of the muffler body 15 (1 / 3d <l <2 / 3d). )
(Hereinafter, this range is referred to as a central portion.)

The plate 16 with a catalyst is provided with a coating layer for improving the bonding of the catalyst layer to the surface of a punching plate 17 (which may be a blind plate), as shown in FIG.
18 is provided, and a catalyst layer 19 is laminated on the surface thereof, forming a sandwich structure.

 Next, the operation will be described.

The temperature of the exhaust gas flowing through the central portion of the muffler body 11 is higher than the periphery thereof as shown in FIG. 4, and is located in the region of the exhaust gas flow having a high temperature, that is, at the central portion of the pipe through which the high-temperature exhaust gas flows. Since the catalyst is located, the hot exhaust gas reacts positively with the catalyst having a large surface area. For this reason, the catalyst starts to react quickly, and the purification performance of the exhaust gas is enhanced. Further, since the plates 16 with catalyst are located at the center of the conduit, the surface temperature of the muffler body 11 becomes lower over the entire area as shown by the solid line a in FIG. Further, the influence of the muffler on the diffuser is reduced as shown by the solid line c in FIG.

7 and 8 show an example of a muffler provided on the right side of the motorcycle body.
A also includes the exhaust gas purification device of the present invention in the exhaust pipe section 11. Other configurations are the same as those shown in FIGS. 1 and 2, and the same reference numerals are given and the description is omitted.

〔The invention's effect〕

As described above, according to the present invention, in an exhaust gas purifying apparatus in which a catalyst-equipped plate is provided inside a muffler constituting an exhaust system of an engine, the catalyst-equipped plate is disposed in a muffler body along a longitudinal direction of an exhaust pipe portion. In addition, each of the inner body and the outer body at the center of the cross section of the muffler body is installed in each of the substantially diametrical directions, and a plurality of plates with a catalyst are arranged side by side in the exhaust pipe at intervals so that high temperature of exhaust gas is high. The catalyst with a large surface area comes into contact with the part, so that the reaction starts quickly, the purification action can be performed well, the purification performance can be improved, and at the same time, the amount of catalyst used can be reduced and the cost can be reduced. Can be. Also, since the plate with catalyst exists near the center of the muffler body,
The rise in the surface temperature of the muffler body is reduced, so that no cost is required for countermeasures against heat damage to the muffler, and the muffler body can be made inexpensive. Further, the filling efficiency by the reflected wave is increased and the output reduction can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an exhaust gas purifying apparatus according to the present invention, FIG. 2 is a side view showing a muffler provided with the exhaust gas purifying apparatus, and FIG. FIG. 4 is a graph showing the temperature distribution of exhaust gas in the pipeline, FIG. 5 is a graph showing the surface temperature distribution of each part of the muffler, FIG. 6 is an output diagram, FIG. 7 and FIG.
FIG. 9 is a side view and a plan view showing another embodiment of the Malahoo equipped with an exhaust gas purifying device. FIG. 9 is a schematic side view showing an example of a motorcycle to which the present invention is applied, and FIG. FIG. 11 is a side view showing a muffler, and FIG.
It is an A line expanded sectional view. 10,10A …… muffler, 11… exhaust pipe section, 12…
… Muffler part, 13… Exhaust pipe, 15 …… Muffler body, 15a …… Inner body, 15b …… Outer body, 16 …… Catalyzed plate, 19 …… Catalyst layer.

Claims (1)

(57) [Claims] An exhaust gas purifying apparatus comprising a muffler constituting an exhaust system of an engine and a plate with a catalyst provided therein.
A plurality of catalyst-equipped plates are installed in the muffler body along the longitudinal direction of the exhaust pipe portion, and in both the inner body and the outer body at the center of the cross section of the muffler body in substantially the same diametrical direction. An exhaust gas purifying device characterized by being arranged in parallel with an exhaust pipe at intervals.