JPS58220914A - Muffler structure of 2-cycle engine - Google Patents

Abstract

PURPOSE:To permit tar portion to be burnt in a tail pipe and facilitate cleaning of the inside of the tail pipe by connecting the tail pipe to the first expansion chamber into which exhaust gas flows at first, in free insertion to an exhaust exit port. CONSTITUTION:The exhaust gas from an exhaust pipe 2 flows into expansion chambers 10, 9, and 8 in succession from the first expansion chamber 6 and is discharged outside from a final expansion chambers 8, passing through a tail pipe 17 connected to said chamber 8. The tail pipe 17 passes through a cylindrical body 7, and the rear edge of the pipe 17 is opened outside, inserted through the rear edge of the cylindrical body 7 and the front edge is opened to the final expansion chamber 8, fixed onto the wall surface of the cylindrical body 7 so as to form an equal surface level. Thus, the tail pipe 7 is set in free insertion for an outside cylinder 4, with the cylindrical body 7.

Description

[Detailed description of the invention] The present invention relates to a muffler structure for a two-stroke engine.

Conventionally, this type of muffler has an outer cylinder connected to an exhaust pipe, a plurality of expansion chambers are defined within the outer cylinder, and a tail pipe connected to the exhaust outlet is connected to the final expansion chamber. The muffler expands the exhaust gas that flows in from the exhaust pipe once in each expansion chamber and then discharges it into the atmosphere from the tail pipe.The exhaust temperature in the muffler is determined because the exhaust heat is radiated from the outer wall of each expansion chamber, which has a large surface area. , decreases toward the downstream side of the exhaust path, and is lowest in the tailpipe.On the other hand, in a 2-cycle engine, the oil supplied to the cylinder is burned along with the intake air, so the exhaust gas from the engine decreases. Contains relatively large amounts of carbon and tar, and depending on the phenomenon, the air vents in the engine may also contain unburned oil.

However, the tar amount is t1 for the previous carbon and tar issue.
In the above muffler, the oil is separated in the tail pipe with the lowest exhaust temperature and collected there, and the unburned oil is also condensed from a gaseous state in the tail vibe and discharged into the atmosphere from the same pipe as smoke. The purpose of the present invention is to reduce the amount of tar remaining in the tail pipe and the exhaust smoke from the tail pipe, and to make it easier to clean the inside of the tail pipe. A cylindrical body extending to the exhaust outlet is removably connected to the first expansion chamber into which the exhaust gas first flows,
A tail pipe that communicates with this cylinder and is formed between the cylinder and the outside is connected to the silkworm, and a tail pipe that passes through the facepiece and opens to the outside from the end of the cylinder is connected to the tail pipe. It is characterized by being attached and supported to the entire cylindrical body.

An example of the implementation of the present invention will be explained from the illustration of a muffler of a two-stroke engine installed in the Auto II Ronto.
In Figure 1, (2) is a 2-stroke JI engine, (2) is the same engine (exhaust hole (not shown)).
The exhaust pipe (3) is connected to the exhaust pipe (2), and the muffler (3) is completely connected to the exhaust pipe (2).

FIGS. 2 and 3 show the structure of the muffler (3) in an enlarged manner, and the following description will be made based on these two figures.

The muffler (3) is connected to the first expansion chamber (6) via the partition wall (5) upstream of the outer cylinder connected to the exhaust pipe (2).
) is formed.

The first expansion chamber (6) is a chamber into which the exhaust gas from the exhaust pipe (2) first flows, and the temperature of the exhaust gas in the first expansion chamber (6) is high.

(7) is a cylindrical body whose rear end is closed and connected to the first expansion chamber (6), and extends to near the rear end of the outer cylinder (4) that is fitted at the exhaust outlet.

The facepiece (7) is connected to the partition wall (5), the cylinder (7) and the outer cylinder (4).
), and insert the partition wall aII defining the expansion chamber (8) (9) (a) between the partition walls (5) and 1 (IIIJ).
The first expansion chamber (6) is supported by IK and can be inserted and removed from the rear end of the outer cylinder (4), and is fixed to the positive wall (4) or the outer cylinder (4) with bolts, etc. Cylindrical body (7
) is communicated with the expansion chamber Q1 at the most downstream part of the outer chamber (4) through a through hole a4.

This expansion chamber 0 (the remaining two expansion chambers (9) and (8) are those that are adjacent to each other and the through hole μ made in the partition wall (αρ).
Communicated by sQQ.

Therefore, the exhaust from the exhaust vibe (2) is transferred from the first expansion chamber (6) to the expansion chamber a1. (9) and (8J), and are discharged to the atmosphere from the final expansion chamber (8) through the tail pipe aη connected to the same chamber (8).

The inside of the tail pipe passes through the inside of the cylinder (7) and its rear end is )4
The rear end of the body (7) is inserted through and opened to the outside, and the front end is also fixed to the wall surface of the cylinder body (7) so as to be l- with it and opens into the final expansion chamber (8). Therefore, the tail The pipe σ can be inserted into and removed from the outer cylinder (4) K together with the cylinder (7).

Since the muffler (3) and the tail pipe are located inside the exhaust tube (7) and are surrounded by a high temperature atmosphere and heated by the exhaust heat, the exhaust gas is discharged in the same pipe Uη. The tar inside is burned and its residue is prevented, and the unburnt oil is also discharged into the atmosphere as a gas without condensing.

In addition, since the cylinder (7) has a relatively large diameter and a large surface 4jt, heat radiation 1-#-114 from the cylinder (7) causes the expansion part (9) uI on the way to the tail vibe Qi. is maintained at a high temperature to prevent R from remaining in the 4(9)01.

In addition, depending on long-term use, carbon and a small amount of tar may accumulate inside the Naarbaia' Li2), but in that case, if the tail pipe IJη is pulled out from the outer surface (4) along with the cylinder body (7), the inside of the pipe can be removed. You can easily do more than one city per city.

As explained hereinafter, the present invention is directed to a 1111 body in which the tail I tube is Ma'Jf into the first expansion chamber into which the exhaust from the exhaust vibe first flows.
By being exposed to a warm atmosphere and being heated by exhaust heat, the exhaust temperature in the tailpipe is maintained at a high temperature.In 1~, it is possible to burn tar in the tailpipe and prevent its residue, as well as to prevent the condensation of unburned oil. can be prevented and reduce exhaust smoke.

Further, since the tail vibe can be inserted into and removed from the outer cylinder along with the cylinder, the pipe can be pulled out from the outer cylinder together with the cylinder to easily clean the inside thereof.

[Brief explanation of drawings]

Figure 1 is a side view showing a motorcycle with A. It is 1u. In addition, in the figure (1)...2 Dikle engine <2)...Exhaust pipe (3)...Muffler (4)...° Outside 1ii (6) (8) (9) Di...Expansion Chamber (7)... body 9η... sol pipe

Claims (1)

[Claims] Exhaust pipe K +d has an outer cylinder that is MA,
In a two-stroke engine muffler in which a plurality of expansion chambers are formed in this outer cylinder and a tail pipe connected to an exhaust outlet is connected to the final expansion chamber, the exhaust gas from the exhaust pipe first flows into the ml expansion chamber. Connect the cylindrical body freely to the exhaust outlet, communicate with this cylindrical body, and connect the four-wall #? ! L, Muffler Mm for a 2-cycle engine, in which the tail pipe is supported with a plate on the front 6α161 body.