JPH06248930A - Muffler of autobicycle engine - Google Patents

Abstract

PURPOSE:To provide the muffler of an autobicycle engine in which noise elimination effect is raised by securing a long baffle pipe by utilizing the whole length of a noise eliminating chamber in a muffler cylinder, and temperature can be changed gradually low by letting exhaust gas flow in order of the first noise eliminating chamber, the second noise eliminating chamber, and the third noise eliminating chamber, and heat damage can be also prevented. CONSTITUTION:The inside of a muffler cylinder 1 is divided into longitudinal three noise eliminating chambers 2, 3, 4, the first noise eliminating chamber 2 and the second noise eliminating chamber 3 are connected to each other by a bent baffle pipe 6 which folds back as U-type in the third noise eliminating chamber 4, the second noise eliminating chamber 3 and the third noise eliminating chamber 4 are connected to each other by a baffle pipe 7, the third noise eliminating chamber 4 is guided to the outside by a tail pipe 8, and the muffler cylinders 1 of the first noise eliminating chamber 2 and the second noise eliminating chamber 3 are formed in a double layers cylinder consisting of an outer cylinder 9 and an inner cylinder 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motorcycle engine muffler.

[0002]

2. Description of the Related Art In a motorcycle, a muffler is connected to an exhaust pipe of an engine so that the muffler silences the exhaust gas. The muffler is tubular and is attached to the side of the vehicle body in the front-rear direction.

In the muffler, for example, as shown in FIG. 2, the muffler cylinder A is divided into three muffle chambers B, C and D by partition plates, and the first muffle chamber B and the third muffle chamber D are baffled. The pipe E is connected, the third muffling chamber D and the second muffling chamber C are connected by the baffle pipe F, and the second muffling chamber C is guided to the outside by the tail pipe G so that exhaust gas is emitted. The baffle pipes E and F and the tail pipe G have different lengths to expand the frequency band of the exhaust gas that can be muffled to improve the muffling effect.

[0004]

The baffle pipes having different lengths are effective, but the length is limited due to the size of the muffler cylinder. In the case of FIG. 2, the exhaust gas flows in the order of the first silencing chamber B, the third silencing chamber D, and the second silencing chamber C, and the third silencing chamber D is higher than the temperature in the second silencing chamber C. It's getting sick and feeling sick. Also, the baffle pipe is used in the muffler room.
Some of them are bent in a letter shape to make them longer, and some baffle pipes are extended to the adjacent silencing chambers to be bent in a U shape to make them longer. See, for example, JP-A-60-81421 and JP-A-53-159437.

In view of the above point, the present invention utilizes the entire length of the muffling chamber in the muffler cylinder to secure a long baffle pipe to enhance the muffling effect and to reduce exhaust gas to the first muffling chamber, the second muffling chamber,
The purpose of the present invention is to obtain a muffler for a motorcycle engine in which the temperature change can be gradually reduced by flowing in the third muffling chamber in order and heat damage can be prevented.

[0006]

In order to achieve the above object, the muffler of the motorcycle engine of the present invention partitions the inside of the muffler cylinder into three silencing chambers in a column, and a first silencing chamber and a second silencing chamber are In the three muffling room, it is connected with a bent baffle pipe that turns back in a U shape, the second muffling room and the third muffling room are connected by a baffle pipe, and the third muffling room is led to the outside by a tail tube, and the first muffling room The muffler cylinder of the second silencing chamber part is formed as a double cylinder of an outer cylinder and an inner cylinder.

[0007]

[Function] The curved baffle pipe extends from the first silencing chamber to the third silencing chamber, is bent into a U-shape in the third silencing chamber, and is folded back.
Since it is connected to the second silencing chamber, it is possible to install a long baffle pipe by utilizing the entire length of the silencing chamber in the muffler cylinder, to expand the frequency band of exhaust gas that can be silenced, and to enhance the silencing effect. Also, the exhaust gas can be made to flow in the order of the first silencing chamber, the second silencing chamber, and the third silencing chamber, so that the temperature can be lowered sequentially,
By making the muffler cylinders of the first muffler chamber and the second muffler chamber a double cylinder of the outer cylinder and the inner cylinder, it is possible to prevent heat damage such as preventing discoloration due to heat of the plating finish on the surface of the muffler cylinder.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The inside of the muffler cylinder 1 is partitioned by a partition plate into three silencing chambers 2, 3, 4 which are a first silencing chamber 2, a second silencing chamber 3, and a third silencing chamber 4. An exhaust pipe is inserted and connected to the front end of the first muffling chamber 2, and a side pipe 5 connects the left and right muffler cylinders 1. The bent baffle pipe 6 is bent into a U shape in the third silencing chamber 4 and folded back to connect the first silencing chamber 2 and the second silencing chamber 3. The second muffler chamber 3 and the third muffler chamber 4 are provided with straight baffle pipes 7
The third silencing chamber 4 is guided to the outside by the tail pipe 8 and discharges exhaust gas from the tail pipe 8. The muffler cylinder 1 in the first muffler chamber 2 and the second muffler chamber 3 is a double cylinder in which the inner cylinder 10 is inserted inside the outer cylinder 9.

The curved baffle pipe 6 extends from the first silencing chamber 2 to the third silencing chamber 4, is folded back in a U-shape, and is connected to the second silencing chamber 3, so that it can be made long. Then, by using the short baffle pipe 7 and the tail pipe 8, it is possible to expand the frequency band of the exhaust gas that can be muffled and enhance the muffling effect. Since the exhaust gas flows in the order of the first silencing chamber 2, the second silencing chamber 3, and the third silencing chamber 4, the temperature inside the muffler cylinder 1 can be gradually decreased from the front side to the rear side, and the first silencing chamber 2 and the By making the part of the second silencing chamber 3 a double cylinder of the outer cylinder 9 and the inner cylinder 10, heat damage such as discoloration of the plating of the surface finish can be prevented.

[0010]

As described above, since the present invention is configured as described above, the curved baffle pipe is inserted to make the long and short lengths by utilizing the entire length of the muffling chamber in the muffler cylinder of the limited length. Baffle pipes can be combined, and the frequency range in which exhaust gas can be silenced can be expanded to improve the noise reduction effect. Further, since the exhaust gas flows from the first silencing chamber to the second and third silencing chambers in order, the temperature inside the muffler cylinder can be sequentially decreased from the front to the rear, and the first silencing chamber and the second silencing chamber By making the muffler cylinder of the part of the double cylinder of the outer cylinder and the inner cylinder, heat damage such as discoloration of plating can be prevented. The weight can be reduced as compared with the case where the whole is formed by the double cylinder by limiting the portion to be the double cylinder.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional side view showing a conventional example.

[Explanation of symbols]

 1 muffler cylinder 2 first silencing chamber 3 second silencing chamber 4 third silencing chamber 6 curved baffle pipe 7 baffle pipe 8 tail pipe

Claims (1)

[Claims] 1. A muffler cylinder is partitioned into three vertical silencing chambers, and the first silencing chamber and the second silencing chamber are connected by a bent baffle pipe that is folded back into a U shape in the third silencing chamber, and the second silencing chamber is provided. And the third silencing chamber are connected by a baffle pipe, the third silencing chamber is guided to the outside by a tail pipe, and the muffler cylinders of the first silencing chamber and the second silencing chamber are formed into a double cylinder of an outer cylinder and an inner cylinder. A motorcycle engine muffler characterized by the above.