JPH0210250Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an exhaust pipe device for motorcycles, etc.

(Conventional technology) When a motorcycle is equipped with a multi-cylinder engine,
For example, in an engine such as a V-shaped four-cylinder engine when viewed from the side, a parallel four-cylinder engine, or a horizontally opposed four-cylinder engine, an exhaust pipe is provided for each cylinder, and the exhaust pipe extends downward and rearward from the exhaust port of each cylinder. If there is only one muffler, gather the rear ends of each exhaust pipe and connect to the muffler via the collecting part.

By the way, as disclosed in Japanese Utility Model Application Publication No. 51-36715, it is known that multiple exhaust pipes are not deformed into a rectangular shape, but are bundled together in a round shape and discharged into other exhaust pipes. It is being

(Problems to be solved by the invention) In the above conventional technology, when welding each exhaust pipe to a circular collective collar, the welding surface is the inner surface of the collar, which makes the work difficult and creates unevenness on the inner wall of the exhaust pipe due to the weld bead. However, when connected to an internal combustion engine or the like, the exhaust performance may deteriorate.

Further, the collar has a mid-protrusion structure, which has the problem of increased weight. The present invention was developed to solve the above problems, and its purpose is to easily, quickly, and accurately convert multiple exhaust pipes into a single muffler without deteriorating exhaust performance. An object of the present invention is to provide an exhaust pipe device that can be connected.

(Means for solving the problem) A means for solving the above problem is to extend a plurality of exhaust pipes from a multi-cylinder engine, and collect the plurality of exhaust pipes through a connector to form a single exhaust pipe. In the exhaust pipe device configured to be connected to a muffler pipe, the connector has a flange portion that fixes each of the exhaust pipes in an inserted state into the muffler pipe, and at least the connection between the outer surface of the exhaust pipe and the flange portion. This is because the surface has a welded part.

(Effects of the above means) According to the above means, a plurality of exhaust pipes can be connected to one muffler pipe by welding via a connector.

(Embodiment) Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic side view of a motorcycle 1, in which a front fork 5 that supports a front wheel 4 is supported in a steerable manner via a head tube 3 at the front end of a frame 2, and 6 is a handle under the front of the frame 2. An engine 7 is mounted on the upper part, and a fuel tank 8 is mounted on the upper part, and a rear fork 10 that supports the rear wheel 9 is pivotably extended from the rear lower part of the frame.
A seat 11 is arranged behind the fuel tank 8.
In addition, 12 in the drawing indicates a reaction unit, and 1
A drive sprocket 3 projects from one side of the transmission case, and drives the drive sprocket 15 of the rear wheel 9, and thus the rear wheel 9, via a chain 14.

In the embodiment, the engine 7 is a water-cooled parallel four-cylinder engine, and a boss portion 7b protrudes from the front of the cylinder portion 7a.
A radiator 16 is disposed between the cylinder head and the gusset 2a hanging down at the front of the frame 2, and exhaust pipes 17 extend from the exhaust port of each cylinder of the cylinder head of the cylinder section 7a. In the example, four exhaust pipes 17 are installed in parallel at the front of the engine, and the details of the exhaust pipes 17 are as shown in FIGS. 2 to 5.

The four exhaust pipes 17 are 1117th, 2217th, and 331st from the right side when viewed from the front as shown in Figure 3.
7. As the 4417th exhaust pipe, the left and right first and fourth pipes 117, 417 are symmetrically bent inward and hang down, and the middle second and third pipes 217, 317 are almost directly connected. Droop. When each part of each exhaust pipe is indicated by 17, the upstream part 17a... protrudes forward, and the intermediate part 1
7b hangs down, the downstream portions 17c extend rearward substantially horizontally, and the downstream portions 17c are disposed below the engine 7 and extend rearward. Each exhaust pipe 117-41
The downstream end 17d of the pipe No. 7 is constructed as follows.

The end 17d of the first tube 117 is placed on top, and the end 17d of the second tube 217 is placed on the bottom, and these are connected by a rectangular cap-shaped connecting plate 18. An exploded perspective view of this part is shown in FIG.
is vertically elongated and includes a surrounding frame portion 18a, and upper and lower holes 18c, 18c are formed in an end plate 18b, which is a flange portion, and end portions 17d, 17d are fitted thereinto and welded to the end plate 18b. Then, lower the end 17d of the third tube 317,
The fourth tube 417 is fitted and welded to an end plate 19b which is a flange portion of a connecting plate 19 similar to that described above, with the end 17d facing upward, and the connecting plate 19 is vertically elongated and includes a surrounding frame 19a.

As described above, the ends of the first tube 117 and the second tube 217 are integrally connected by the connecting plate 18 to form a unit, and the ends of the third tube 317 and the fourth tube 417 are connected to the connecting plate 18. 19 to form a unit, which is then arranged in a line.

20 is a muffler, and upstream of this is a communicating pipe section 20.
a, and a collecting pipe 21 is provided at the downstream end of the portion 20a.
The downstream end 21a, which is a flange portion, is joined. The upstream part 21b of the collecting pipe 21 has a rectangular surrounding frame shape, and the above-mentioned connecting plates 18, 1 are attached to the surrounding frame part 21c, which is a flange part.
9 are fitted and welded.
As a result, the muffler 20 and the four exhaust pipes 117 to 4
17 will be joined by a connector consisting of connecting plates 18, 19 and a collecting pipe 21. This state is shown in FIGS. 2, 3, and 5.

(Effects of the invention) As is clear from the above, according to the invention, in the assembly and assembly process of the exhaust system of a motorcycle, a plurality of exhaust pipes are brought together via a connector having a flange portion, that is, the outer surface of the exhaust pipe is Since the muffler pipe is connected to the muffler pipe so that a welded portion is provided on the joint surface between the flange portion and the flange portion, the work is facilitated, the assembly workability is improved, and it is advantageous for mass production.

In addition, the exhaust pipe inner wall is free from unevenness due to weld beads, which prevents deterioration of exhaust performance.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view of the motorcycle, Fig. 2 is a side view of the exhaust system, Fig. 3 is a front view thereof, and Fig. 4 is an exploded perspective view of the same.
FIG. 5 is a longitudinal sectional view of the main part. In addition, 7 in the drawing is an engine, 17,117~417
is an exhaust pipe, 18 and 19 are connecting parts, 20 is a muffler,
21 is a gathering part.

Claims (1)

[Scope of utility model registration request] In an exhaust pipe device in which a plurality of exhaust pipes extend from a multi-cylinder engine, and the plurality of exhaust pipes are gathered together via a connector and connected to a single muffler pipe, the connector is configured to connect each exhaust pipe to a single muffler pipe. An exhaust pipe device comprising a flange portion for fixing a pipe in an inserted state into a muffler pipe, and a welded portion at least at a joint surface between the outer surface of the exhaust pipe and the flange portion.