JPS6141951Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a muffler for an internal combustion engine used in a motorcycle or the like.

For items such as motorcycles where the muffler is exposed, the quality of the appearance determines the product value.
Mufflers are also coated with chrome plating or heat-resistant paint to improve their appearance, as well as to prevent rust.

However, high-temperature exhaust gas flows inside the muffler, and the walls that the flow directly collides with are particularly exposed to high temperatures, which can cause problems such as discoloration of the plating applied to these areas and deterioration of the heat-resistant coating. Ta.

In particular, in order to increase the silencing effect, which is the original function of the muffler, the communication pipe that passes through the silencing chamber is lengthened, and when the overall length of the muffler is limited, it is necessary to extend the exhaust discharge part of the communication pipe to the vicinity of the end plate. This will cause discoloration of the end plate.

In order to solve this problem, the conventional method was to double the end plates, but this inevitably increased the cost.Moreover, in order to compensate for the increase in the amount of overhang of the communicating pipe due to the length of the communicating pipe, support was required. They also added new partition boards for use.

This idea was made to solve these problems, and is designed to prevent discoloration of the end plate when extending the communication pipe to the maximum length to increase the silencing effect in a space limited by the design layout. It provides a simple and effective device and will be explained below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which a communicating tube 2 is inserted into an eccentric hole of a partition plate 1 and welded.

Then, a baffle plate 3 made of a substantially L-shaped thin plate is placed on the exhaust discharge part 4 of the communication pipe 2 so that its other side covers the outlet hole of the communication pipe with a gap provided from the exhaust discharge part 4. Weld to.

The communication pipe 2 assembled in this manner is inserted into the muffler body 5, and spot or plug welded at the flange portion of the partition plate 1.

At the rear end of the muffler body 5, an end plate 7, which is welded after inserting the tail pipe 6 into a burring hole in the center thereof, is inserted, and its flange portion is spot or plug welded to the muffler body 5.

After that, the end of the muffler body 5 is curled.

The outer surface of the end plate 7 is plated or heat-resistant painted to improve appearance and corrosion resistance. A portion of the muffler body 5 divided by the partition plate 1 becomes a silencing chamber 8.

Next, its effects will be explained.

High-temperature exhaust gas passing through the exhaust pipe from the engine passes alternately through the muffling chamber 8 and the communication pipe 2 to be muffled. After passing through the communication pipe 2, it collides with the baffle plate 3, is muted in the muffling chamber 8 while changing its flow direction, and is further discharged into the atmosphere from the tail pipe 6.

In terms of noise reduction, the longer the communication pipe 2 is, the more effective it is in muffling low-frequency components. However, the overall length of the muffler is naturally limited by design, and if the communication pipe 2 is made longer, high-temperature exhaust gas will be directly injected into the end plate 7. However, in the present invention, since there is a simple baffle plate 3 between the exhaust discharge part 4 of the communication pipe 2 and the end plate 7,
The end plate is locally heated by high heat,
It is possible to prevent coating layers such as plating or paint from discoloring and peeling off.

This idea has a simple configuration as described above, and can prevent discoloration of the plating of the end plate or deterioration of the heat-resistant coating by simply installing a roughly L-shaped baffle plate at the outlet end of the communicating pipe without impairing the sound deadening performance. This can be achieved effectively and has great practical value.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, and is a longitudinal sectional side view, FIG. 2 is a view taken in the direction of the arrows in FIG. 1, and FIG. 3 is a view taken in the direction of the arrows in FIG. 2. 1... Partition plate, 2... Communication pipe, 3... Baffle plate,
4...Exhaust discharge part, 5...Muffler body, 6...
Tail pipe, 7...end plate, 8...muffling chamber.

Claims (1)

[Scope of utility model registration request] In a muffler in which the interior is partitioned into a plurality of silencing chambers, a communicating pipe is provided that penetrates the silencing chamber, and the outlet of the communicating pipe is arranged toward the end plate of the muffler, only at the outlet end of the communicating pipe is an outlet of the communicating pipe. 1. A muffler for an internal combustion engine, characterized in that a substantially L-shaped baffle plate is attached so as to cover the end plate with an interval, and a gap is provided between the baffle plate and the end plate.