JP3307088B2 - Small engine muffler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A conventional muffler for a small engine is formed by joining two bodies formed of a steel plate molded product or an aluminum die-cast molded product. In order to use the sound absorbing material, the sound absorbing material is prevented from scattering. For this reason, a muffler made of a steel sheet molded product requires a holding member such as a metal lath, and a muffler made of an aluminum die-cast molded material needs to provide an integral plate-shaped projection on the body.

[0003]

If a muffler of a conventional small engine is to be used with a sound absorbing material, the muffler composed of a steel sheet molded product increases the number of parts and costs, and is formed of an aluminum die cast molded product. The muffler requires plate-like projections that are provided integrally with the body. If the plate-like protrusions are provided with a large draft angle for die-cutting, the gap between the plate-like protrusions and the plate-like protrusions will be reduced when two bodies are joined. When a large gap is formed, the effect of preventing the sound absorbing material from scattering is reduced, and when the draft angle of the plate-shaped projection is reduced,
It is necessary to increase the thickness of the plate-like projection or to attach a reinforcing rib to the plate-like projection, and there is a disadvantage that the weight of the muffler increases.

An object of the present invention is to solve the above-mentioned drawbacks and to provide a muffler for a small engine which effectively uses a sound absorbing material.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to provide a muffler for a small engine comprising two bodies made of an aluminum die-cast product and a sound absorbing material, and two mufflers inside the two bodies. Projecting from the mating surface of the body,
This can be achieved by providing a plurality of trapezoidal or triangular plate-like projections for securing a well-drafted sound absorbing material which, when matched, do not interfere with each other and form a suitable gap.

[0006]

According to the muffler of the small engine constructed as described above, the two bodies formed of the aluminum die-cast molded products protrude from the mating surfaces of the two bodies and do not interfere with each other when they are matched. Providing a plurality of trapezoidal or triangular plate-shaped projections that form an appropriate gap and secure the sound absorbing material with sufficient drafting to obtain the opening area necessary for sound absorption without scattering the sound absorbing material Can be.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the muffler 5 of the present invention is composed of a body 1 and a body 2 which are made of an aluminum die-cast product.
The body 1 is attached to the cylinder 6 by screws 7, the body 2 is attached to the body 1 by screws 8, and the sound absorbing material 3 is inserted into the bodies 1 and 2. The body 1 and the body 2 project from the mating surface of the body 1 and the body 2 and form a suitable gap without interference with each other when the body 1 and the body 2 are matched. A triangular plate-like projection 4 is provided. The sound-absorbing material 3 is fixed by the plate-shaped protrusions 4, and when the body 1 and the body 2 are matched with each other, the plate-shaped protrusions 4 form an appropriate gap, so that the sound-absorbing material 3 is required for sound absorption without scattering. An opening area can be obtained.

[0008]

According to the present invention, two bodies formed of an aluminum die-cast molded product protrude from the mating surfaces of the two bodies, and when they are matched, an appropriate gap is formed without interfering with each other. By providing a plurality of trapezoidal or triangular plate-like projections for fixing the sound absorbing material with a sufficient draft angle, it is possible to obtain an opening area required for sound absorption without scattering the sound absorbing material, Can be used effectively.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment in which a muffler of a small engine according to the present invention is mounted on a cylinder.

FIG. 2 is a front view of the body 1 of FIG. 1 as viewed from a mating surface.

FIG. 3 is a front view of the body 2 of FIG. 1 as viewed from the mating surface.

[Explanation of symbols]

Reference numerals 1 and 2 denote a body, 3 denotes a sound absorbing material, 4 denotes a trapezoidal or triangular plate-like projection, and 5 denotes a muffler.

Claims (1)

(57) [Claims] 1. A muffler for a small engine, comprising two bodies made of an aluminum die-cast molded product and a sound absorbing material, and protruding from the mating surfaces of the two bodies inside the two bodies. A muffler for a small engine, comprising a plurality of trapezoidal or triangular plate-like projections for fixing a sound absorbing material, which have an appropriate gap without interference when two bodies are matched.