JPS6012881Y2 - Improved resonant silencer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resonant muffler, and particularly to an improved structure of a resonant muffler that is extremely effective in muffling noise in the low frequency range.

Various types of mufflers have been developed in the past to muffle noise propagated in gas passages, but one type of muffler is a resonance type muffler, which consists of a small hole and an air layer behind it. A device that forms a resonator and absorbs sound energy through resonance absorption, suppressing intake noise propagated through the intake passage of an air cleaner that purifies the air sucked into the engine of a vehicle, for example. It is used as an intake ν zonator, etc.

By the way, since these type of silencers have traditionally been made of iron, they are heavy, and therefore, of course, they are not desirable from the perspective of reducing the weight of Imada Koo vehicles. The process of brazing steel plates is complicated and requires a large number of man-hours, as it is necessary to form a resonator through work, etc., which also contributes to high costs. However, there are many problems inherent in the productivity of the silencer itself, such as the awning.

. Therefore, in order to solve this problem, the present applicant previously proposed Utility Application No. 55783195.
We proposed a resonant silencer manufactured by Hewei-Gyeong Co., Ltd. (Reference No. 1983-8346).

As shown in FIG. 1, a silencer 1 is constructed from two vessel elements 2 and 3 divided into left and right parts.

These vessel elements 2 and 3 are respectively a cylindrical body (circular, cylindrical) part 2ae3a and a pipe part 2b penetrating the bottom thereof.
.

Then, the container body elements 2 and 3 are butted together so that the openings of the bottomed cylindrical body portions 2a*3a face each other,
Further, by vibration welding the abutting portions 8 of the cylindrical body portions 2a and 3a, the two pipe portions 2bt3b
The inlet portion 4 and the outlet portion 5 for the gas that propagates noise are formed by the two bottomed cylindrical body portions 2ae3a, and a sealed resonance chamber 7 is formed by the two bottomed cylindrical body portions 2ae3a.

Furthermore, the abutting portions 6 of the pipe portions 2b and 3b form a slit with a predetermined gap t without being brought into contact with each other, and through this slit 6,
The inlet section 4 and outlet section 5, which are constituted by the pipe sections 2b and 3b, and the resonance chamber 7 are communicated with each other.

Therefore, by simply combining the body elements 2 and 3, which are integrally formed of synthetic resin, and vibration welding only the abutting portion 8, the desired silencer 1 can be obtained at once. As a result, there is no longer any need for the complicated and troublesome process of attaching steel plates, and there is also no need for difficult hole drilling, which significantly improves the workability of manufacturing silencers. Unlike the conventional iron material, the container component material is synthetic resin, which reduces the weight and contributes to the weight reduction of the vehicle. □The above-mentioned problems of the conventional method can be solved for the time being. It is.

□ □However, according to the inventors' study, it has become clear that this method contains many problems that still need to be solved.

In other words, in the resonance type silencer as described above, the narrower the gap t between the two pipe parts 2b and 3b, the more the low frequency reconnaissance noise will be muffled. It has been found that in some cases, no matter how narrow the gap t is, it may not be possible to obtain a sufficient sound-dampening effect in a mound to which sound-muffling is being attempted.

Therefore, there has been a need to develop a silencer with a simple structure that can effectively silence noise in the low frequency range.

'N, -゛(1,l'''7') This invention was made against this background, and...
The purpose is to provide a resonant muffler which is effective in muffling noise in the low frequency range that cannot be muffled by the resonant muffler described above and which has an extremely simple structure.

And, in order to achieve this purpose, □゛The present invention:
The bottomed cylindrical body part and the pipe part penetrating the bottom part of 1) and 7y)g
By using two 2# synthetic resin molded products, the open ends of their cylindrical body parts are butted against each other and vibration welded, thereby creating an inlet for the gas that propagates noise in these two pipe parts. In addition to configuring the section and the exit section, two? A resonance type ρ that forms a sealed resonance chamber in the bottomed cylindrical body of
In the muffler, the gas inlet and outlet opening into the resonant chamber are connected by an integral T-shaped tube made of elastic material, so that the noise propagating gas can flow through the single-shaped tube. The sound propagation gas passage communicates with the resonance chamber through the legs of the sound propagation chamber.

Hereinafter, the present invention will be explained in more detail based on embodiments shown in the drawings.

2 to 4' are diagrams showing a resonance type muffler according to an embodiment of the present invention.

In these figures, the silencer 11 is composed of earthen vessel elements 12 and 13 and a T-tube 20, which are divided into left and right parts at the center of the silencer 11. It is integrally constituted by bottomed cylindrical body portions 12a, 13a and pipe portions 12b, 13b passing through the bottom portions, each of which is formed at once from synthetic resin by an integral molding method.

These vessel elements 12 and 13 are abutted against each other so that the openings of the bottomed cylindrical body parts 12a and 13a are opposite each other. ．． The abutting portion 11 of the mesh 3a is vibration welded, so that the two pipe portions 12b and 11 are connected by vibration welding.
″-Inlet part 141 and outlet part 5 of electric sound that propagates electric sound
and two bottomed cylindrical body parts 12a,
A sealed resonance chamber 17 is formed at 13a.

! - As shown in FIG. 4, the T-shaped tube 20 includes a circular tubular head/body portion 20a and circular tubular legs that protrude from the central portion and are narrower than the tubular body portion 20a; *, Hj, 2o
'b-! : It is made up of 100% rubber and is made into one piece with a rubber band.

The left and right ends of the trunk 20a of the T-shaped tube 20 are 1
The noise propagating gas =p:= which opens into the resonance chamber 17 is connected to the outlet port n to form a noise propagating gas 1.1.

Also, the neck portion 20 of the T-shaped tube 20. b is the resonance chamber 111
The noise propagation gas passage 19 is open to 8f,
It communicates with the resonant chamber 17 and becomes "namely".

Note that in this embodiment, t is the pipe portions 12b and 13b.
and the cylindrical body portion i2a+13a are arranged concentrically.

Therefore, with such a configuration number, first, the vessel body elements 1 and 3 are made in advance from integral shapes of synthetic resin, and the T-tube 20 is made from rubber or the like, and then the corresponding parts are made in advance. The noise propagation gas inlet 14 and outlet 15 are inserted into the left and right ends of the body 20a of the T-shaped tube 20 to form a noise propagation gas passage 19, while the vessel elements 12 and 13 are inserted from the left and right. In addition, the desired silencer 11 can be obtained all at once by simply welding only the abutting portions 18 of the cylindrical body portions 12a and 13a, so manufacturing is extremely simple and assembly is a simple task. It is highly durable and lightweight, and can meet today's demands for lighter vehicles.

By the way, it is generally known that in a resonance type muffler, the resonance frequency fp is expressed by the following equation.

However, V: Resonance chamber capacity C: Sound speed S: Neck cross-sectional area 1: Neck length Therefore, if the resonance chamber capacity V is constant, the longer the neck length I or the smaller the neck area S, the lower the frequency. This is effective in muffling noise in the area, so in this embodiment as well, by using a T-tube with a simple structure consisting of a trunk 20a and legs 20b, the neck length is significantly reduced compared to the conventional one. This makes it possible to muffle noise in the desired low frequency range.

Furthermore, when sealing the two vessel elements 12 and 13 by joining, they are generally joined by vibration welding, so a considerable stress is applied to the leg (neck) 20b of the T-tube 20. However, in this embodiment, since the T-tube 20 is integrally formed with rubber (elastic material), the stress applied to the neck 20 does not cause damage to the neck.
Furthermore, it is also possible to prevent a gap from occurring at the fitting portion between the neck portion 20b, the inlet portion 14, and the outlet portion 15.

The present invention is by no means limited to the specific examples shown, and various improvements and changes may be made based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

For example, on the upper side, the pipe parts 12b and 13b and the cylindrical body part 1
2a and 13a are arranged concentrically, but they can also be arranged eccentrically.

As detailed above, the resonant silencer according to the present invention is extremely effective in silencing noise in the low frequency range, and has a simple structure and is extremely easy to manufacture. It has many excellent effects such as cost reduction, and has great industrial significance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional resonance type muffler, and FIG. 2 is a perspective view of a resonance type muffler according to an embodiment of the present invention.
3 is a longitudinal sectional view of FIG. 2, and FIG. 4 is a perspective view of the T-shaped tube according to the present invention. 1.11: Resonant silencer, 2, 3, 12, 13: Vessel element, 2a, 3at 12a, 13a: Bottomed cylindrical body part,
2b, 3b, 12b, 13b: Pipe section, 4, 14: Inlet section, 5, 15: Outlet section, 7.17: Resonance chamber, 8.18
: Butt part, 19: Noise propagation gas passage, 20: T-shaped pipe. 20a: head (torso), 20b: legs (neck).

Claims (1)

[Claims for Utility Model Registration] Two integrated synthetic resin products consisting of a cylindrical body with a bottom and a pipe passing through the bottom are used, and the open ends of the cylindrical bodies are mutually connected. By butting them together and vibration welding them, these two pipe sections form an inlet and an outlet for the gas that propagates the noise, and the two bottomed cylindrical bodies form a sealed resonant chamber. In the resonance type muffler, the gas inlet and outlet opening into the resonance chamber are connected by seven T-shaped tubes made of elastic material to form a passage for the noise propagating gas. An improved resonant silencer characterized in that the noise propagation gas passage and the resonance chamber are communicated through the legs of the T-shaped tube.