JP3788144B2 - Vehicle muffler spark arrester - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spark arrester for a muffler (muffler) for a vehicle such as an off-road motorcycle.
[0002]
[Prior art]
Motorcycle mufflers usually have a cylindrical shape, and the exhaust pipe of the engine is connected to the front end of the muffler, and the exhaust gas exhausted from the engine is silenced in multiple expansion silencing chambers inside the muffler, and then externally from the tail pipe at the rear end of the muffler. To be released.
And, off-road vehicles of the type that can be driven off-road, a spark arrester is provided, and this spark arrester is arranged on the front side of the tail pipe of the exhaust gas discharge port at the rear end of the muffler. Is attached to prevent the sparks contained in the exhaust gas from being released outside the muffler.
[0003]
For example, as shown in FIG. 4, the spark arrester is attached to a front part B1 in the expansion chamber of the tail pipe B at the rear end of the muffler cylinder A with a wire mesh filter C having the same diameter as the tail pipe B. The exhaust gas is filtered at C to remove the spark, and the spark is prevented from being released from the tail pipe B to the outside of the muffler.
[0004]
Here, the spark arrester is a device that prevents the sparks from being scattered outside the muffler by filtering the exhaust gas with a wire mesh filter as described above. If the filter is clogged, it will cause the engine output to drop, and it must be cleaned regularly. If the filter area of the filter is small, it must be cleaned frequently, so the filter area should be as large as possible. To increase the filter area, however, increase the filter length of the arrester or increase the diameter of the tail pipe. Can be considered.
[0005]
[Problems to be solved by the invention]
However, the tail pipe B has a predetermined diameter and length because of the relationship between engine performance and exhaust noise. If the filter attached to the front of the tail pipe by direct welding is too long, Increasing the length of the filter C, such as the length becoming longer and the mounting of the vehicle in a trouble, also has a structural limit of the muffler cylinder A. On the other hand, if the tail pipe B is made thick, the exhaust sound muffling performance (exhaust sound volume attenuation performance, sound quality) also deteriorates, so it cannot be thickened without darkness.
[0006]
Here, as shown in FIG. 5, there is a proposal in which a filter funnel-shaped spreading bracket D is attached to the outside of the tail pipe B, and a filter C having a large diameter is connected to the spreading bracket D (Japanese Patent Laid-Open No. Hei 8). No. 61046 or JP-A-10-266828). In this way, the purpose is to improve the performance of the filter C while maintaining the performance of the tail pipe B.
However, as shown in FIG. 5, when the filter C is connected to the above-mentioned spreading metal fitting D, not only the structure becomes complicated to attach the spreading metal fitting D, but also the number of places to be welded while maintaining airtightness increases. There is a problem of high cost.
[0007]
In view of this point, the present invention connects a filter to the front end of the tail pipe to increase the filter capacity, keeps engine performance and exhaust sound good, and the cover is easy to attach and detach, and the filter is easy to clean. An object is to provide an inexpensive vehicle muffler spark arrester.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configuration.
The present invention includes a tail pipe that is attached to the tail flange of the muffler and is detachably attached to the muffler, and a cylindrical filter that is connected to the front portion of the tail pipe and has its front end closed by a closing plate . in the spark arrester muffler for a vehicle, detachably a bottomed cylindrical cover bored a plurality of throttle holes in the cylindrical side surface to said closing plate so as to cover and said filter to have a gap on the entire surface of the filter A muffler spark arrester for a vehicle , wherein the bottomed cylindrical cover and the filter are detachably mounted together with a tail pipe from the muffler.
And the throttle hole of a cover can be provided in the part which faces the front part of a filter.
[0009]
A filter connected to the front end of the tail pipe prevents the passage of sparks contained in the exhaust gas and prevents the discharge of sparks from the tail pipe. In addition, the throttle hole of the cover that covers the entire surface of the filter close to each other can determine the number and size of the throttle holes from the relationship between the engine performance and the exhaust noise, so that the tail pipe may be thick. For this reason, the area of the filter can be increased.
By providing the throttle hole in the cover at the front part of the filter, the same effect as that obtained by separating the tail pipe from the front end and making the tail pipe long can be obtained.
The cover is detachable from the filter, and the tailpipe is detachably attached to the muffler. Remove the tailpipe from the muffler and remove the cover from the filter at regular intervals. It can be cleaned and the filter can be prevented from clogging.
Further, since providing a gap between the filter and the cover, it is possible to prevent partial blockage of filters, can extend the cleaning cycle can be effectively used filtering surface of the filter, stable spark arrester is long-term Its performance can be maintained.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to FIGS.
The muffler 1 has a cylindrical shape and is long in the front and rear direction, and the front portion is thin in a trumpet shape.
Further, a conical side-shaped attachment portion 1t, which is constricted toward the rear at the center, is welded and fixed to the tail end of the muffler 1, and a plurality of screws are attached by overlapping the tail flange 3 on the attachment portion 1t. Fasten with 4 and connect. The tail flange 3 has a substantially funnel shape as a whole consisting of a substantially conical side surface shape portion 3a having a shape along the rear surface of the mounting portion 1t and a hollow cylindrical portion 3b.
The inside of the muffler 1 has a plurality of expansion and silencing chambers 6 formed by a substantially basin-shaped partition plate 5 whose peripheral edge is fixed to the inner wall of the muffler 1 by welding or the like, and the expansion and silencing chambers 6 penetrate the partition plate 5. The communication pipe 7 is fixed and communicated.
[0011]
A spacing plate 10 is welded and fixed to the rear end of the muffler 1 so as to close the central hole 8 on the inner side of the cylindrical portion 3b of the tail flange 3, and a tail pipe 9 is inserted into the central hole portion of the spacing plate 10; By fixing by welding, the tail pipe 9 is attached via the spacing plate 10. The tail pipe 9 may be set so as to be directly attached to the center hole 8 of the tail flange without providing the spacing plate 10.
In FIG. 1, the exhaust flow is indicated by arrows.
[0012]
In the embodiment, the tail pipe 9 has a straight central axis and is attached obliquely with an angle with respect to the axis of the muffler 1, and the exhaust of the tail pipe 9 is attached to the motorcycle with the muffler 1 mounted. The exit direction is diagonally downward and rearward.
To the front end of the tail pipe 9, a wire mesh filter 12 formed in a cylindrical shape with the front end closed by a closing plate 11 is fixed by welding and connected.
The cover 13 has a bottomed cylindrical shape, and is fixed on the filter 12 fixed to the tail pipe 9. In this case, the cover 13 has an inner surface close to the outer surface of the filter 12 so that the filter 12 is inserted therein, and the cover 13 is closed at the center of the bottom of the cover 13 by using a fastening screw 14 so as to be detachable. It comes to be attached.
The cover 12 is provided with a plurality of small apertures 15 in a portion facing the front portion 12 f of the filter 12.
[0013]
Exhaust gas in the muffler chamber 6 at the rear is throttled by a plurality of throttle holes 15 in the cover 13. When passing through the filter 12, the spark is removed and discharged from the inside of the filter 12 through the tail pipe 9. Since the exhaust gas can be throttled by a plurality of small apertures in the cover 13 so as to obtain engine performance and good exhaust noise, the tail pipe 9 may be thick and the filter 12 connected to the tail pipe 9 is also thick. Large filtration area and low resistance.
Since the cover 13 can be easily attached and detached with the fastening screw 14, the filter 12 can be easily cleaned. Further, by providing a plurality of narrow apertures 15 in the cover 13 in a portion that becomes the front portion of the filter 12, the same effect as that obtained by increasing the length of the tail pipe 9 can be obtained. In this way, the filter 12 having a large filtration area can be connected to the front end of the thick tail pipe 9 to improve the filtration performance. Further, since the filter 12 is connected to the front end of the tail pipe 9, the structure is simple and can be manufactured at low cost.
[0014]
【The invention's effect】
As described above, since the present invention is configured as described above, a plurality of small apertures in the cover that covers the filter on the front side of the tail pipe allows the exhaust gas flow to match engine performance and good exhaust sound. The exhaust gas can be throttled. For this reason, the tail pipe may be thick, the filter connected to the tail pipe is also thick, the filtration area is large, and the spark filtration performance can be improved. In addition, since the filter is directly connected to the tail pipe, the structure can be simplified and the cost can be reduced.
[0015]
Further, by providing a plurality of throttle holes in the cover at the front part of the filter, it is possible to obtain the same noise reduction performance improvement and sound quality improvement effect as when the tail pipe is separated from the tail pipe and the tail pipe is lengthened.
Further, since the throttle hole is located on the side surface of the cover, the exhaust flow does not flow linearly toward the tail pipe, and the exhaust flow flows sideways, improving the silencing characteristics.
Further, since the cover can be attached and detached with fastening screws, it is easy to attach and remove, and the filter can be easily cleaned. Since the cover can be removed, the volume and sound quality can be adjusted to any desired level by replacing the cover with a different diameter or length.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view showing an embodiment of the present invention.
FIG. 2 is a longitudinal side view of a single cover showing an embodiment of the present invention.
FIG. 3 is an external side view of the entire muffler showing the embodiment of the present invention.
FIG. 4 is a schematic longitudinal sectional view showing an example of the prior art.
FIG. 5 is a schematic vertical sectional view showing another example of the prior art.
[Explanation of symbols]
1 Muffler 3 Tail flange 9 Tail pipe 11 Closing plate 12 Filter 13 Cover 14 Fastening screw 15 Restriction hole

Claims (2)

A vehicle muffler having a tail pipe attached to the tail flange of the muffler and detachably attached to the muffler, and a cylindrical filter connected to the front portion of the tail pipe and closing the front end with a closing plate . At Spark Alester,
A bottomed cylindrical cover bored a plurality of throttle holes in the cylindrical side surface so as to cover the entire surface and the filter to have a gap between the filter and attached detachably to the closing plate, the bottomed cylinder A muffler spark arrester for a vehicle , wherein the cover and the filter are detachably mounted together with the tail pipe from the muffler.   2. The spark muffler for a vehicle muffler according to claim 1, wherein the throttle hole of the cover is provided in a portion facing the front portion of the filter.

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