JPS621383Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a muffler for use in internal combustion engines, such as general-purpose internal combustion engines.

This type of silencer is required to be small and lightweight, and is made of plate material such as iron. However, the temperature of the exhaust gas from the engine is high, and the outer plate of the muffler is heated by the exhaust gas, causing its surface temperature to rise.

Conventionally, insulating materials such as asbestos were placed inside the outer panels to prevent the surface temperature from rising. However, the insulating materials prevent heat from escaping from the outer panels, so the exhaust gas remains at a high temperature. There was a problem with it being ejected.

The purpose of the present invention is to solve the above-mentioned problems.The outer surface of the silencer body 1, which is made of a metal plate such as iron and has an exhaust inlet pipe and an exhaust pipe, is coated with an aluminum alloy cast skin. A layer 2 is formed, and cooling fins 2a are integrally formed on the skin layer 2.

In the embodiment shown in the figure, the muffler body 1 is formed by dividing the muffler body 1 into two parts 1a and 1b using a metal plate, etc., and sandwiching the partition plate 3 at the opening seam of the muffler body 1 to face each other, and caulking the periphery of the seam to form the muffler body 1. do. 4 and 5 are partition plates 3
The expansion chamber 3a formed in the above communicates the two chambers 4 and 5 through a communication hole provided in the partition plate 3. Reference numeral 6 denotes an exhaust gas introduction pipe (not shown in the figure) for guiding exhaust gas from the engine into the expansion chamber 4 through a hole 6a, the tip of which is abutted against the opposite wall of the muffler body 1, and is sealed with a blind plate 7 for energy absorption. A chamber 6b is formed. Reference numeral 8 denotes an exhaust pipe that discharges the exhaust gas from the expansion chamber 5 to the atmosphere.

Then, using a mold (not shown in the figure) using the silencer main body 1 provided with the above-mentioned exhaust inlet pipe 6 and exhaust pipe 8 as a core material, aluminum alloy is cast over the entire outer surface of the muffler body 1 to form a skin layer 2, and at the same time, heat is dissipated. The fins 2a are integrally formed.

As described above, in the present invention, the cast skin layer 2 of aluminum alloy is formed on the outer surface of the silencer body 1, so that the heat capacity is increased by the skin layer 2, and the heat is dissipated by the heat dissipation fins 2a. In addition to preventing the surface temperature from rising, the temperature of the exhaust gas inside the muffler is reduced, and the temperature of the exhaust gas exiting from the exhaust pipe 8 can be reduced.

Furthermore, when casting the skin layer 2 on the surface of the silencer body 1, the body 1 becomes the core material and no core or the like is required. Since the pipes 4 and 5 are wrapped around each other, there is no need to use baseboards or the like to form holes for attaching the pipes 4 and 5, and manufacturing is extremely easy.

Furthermore, the above-mentioned skin layer 2 can reduce transmitted sound from inside the muffler main body 1. Moreover, since the skin layer 2 is made of aluminum alloy, it is lightweight;
Moreover, since the muffler main body 1 is reinforced with the skin layer 2, it is possible to use a thin plate.

Note that when the muffler main body 1 is formed of an aluminized steel plate, the adhesion with the skin layer 2 is improved, and the cooling effect of the exhaust gas inside the muffler main body can be further improved.

[Brief explanation of the drawing]

The figures show an example of the muffler of the present invention, in which Fig. 1 is a longitudinal sectional front view, Fig. 2 is a side view, and Fig. 3 is a plan view. 1 is the silencer body, 2 is the skin layer, 3 is the partition plate,
4 and 5 are expansion chambers, 6 is an exhaust introduction pipe, and 8 is an exhaust pipe.

Claims (1)

[Scope of utility model registration request] A silencer in which an aluminum alloy cast skin layer is formed on the outer surface of a silencer body made of a metal plate such as iron, which is provided with an exhaust inlet pipe and an exhaust pipe, and cooling fins are integrally formed on the skin layer.