JPH0341714Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a diaphragm muffler for alleviating noise from emitted air, etc.

(Prior Art) Although there are a wide variety of types of silencers, it is difficult to say that only known silencers are sufficient when adapting them to specific uses.

(Problem to be solved by the invention) In recent years, transport-type medical oxygen concentrators that can be used at home have been commercially available, but when they are used, they generate noise when releasing air into the atmosphere. need to be alleviated.

The present invention was developed primarily to deal with the above-mentioned noise, and an object of the present invention is to provide a diaphragm muffler that has a simple and compact structure and yet can achieve the required noise reduction.

(Means for Solving the Problems) In order to achieve the above object, the diaphragm muffler of the present invention is provided with an exhaust inlet at the center of the front wall of the rubber cylindrical hollow part and an exhaust outlet at the center of the rear wall. A partition wall with a through hole in the center is provided horizontally inside the hollow part to divide the hollow part into a plurality of compartments, and a roughly drum-shaped rubber hollow core is installed in each of the compartments. In addition, the front and rear surfaces of each hollow core are made into wave-shaped sound wave diffusing surfaces with a sharp protrusion in the center, and the top and bottom of the waves have a large number of small-diameter through holes that communicate with the hollow part of the core. Further, the hollow part of the core is divided into front and rear halves by a partition plate, and each chamber is filled with a sound absorbing material.

At this time, it is preferable to make the starting end of the outlet pipe forming the exhaust outlet project a certain length into the rubber cylindrical hollow part in order to enhance the sound deadening effect.

(Function) The sound wave diffusion surface can disperse the sound flowing in from the exhaust inlet in its radial direction, and the hollow core, the sound absorbing material loaded therein, and the small diameter through holes provide effective resonance sound damping. In addition, the rubber walls of the rubber cylindrical hollow part and the rubber hollow core function as a diaphragm, converting the vibrations of the walls induced by sound vibrations into thermal energy, and transmitting the sound vibrations over a wide area. It can attenuate across frequencies, and can also perform expansion silencing due to the space defined by the two.

(Example) Hereinafter, a specific example of the present invention will be described based on the accompanying drawings.

Figure 1 is a longitudinal cross-sectional view of the product of the present invention, taken along the line X-X in Figure 2, and Figure 2 is a cross-sectional view taken along the line Y-Y in Figure 1.
FIG.

In the figure, reference numeral 1 denotes a cylindrical hollow part made of rubber, which includes cylindrical casings 2 and 3 made of rubber such as chloroprene, and a cylindrical joint 4 made of rubber also made of chloroprene etc., which is provided with a partition wall 4a to be described later. Consisting of Reference numeral 5 denotes an exhaust inlet formed at the center of the front wall of the cylindrical hollow part 1 made of rubber, and is formed by attaching an inlet pipe 6 made of rubber to the cylindrical casing 2. Reference numeral 7 denotes an exhaust outlet formed at the center of the rear wall of the rubber cylindrical hollow portion 1, which is formed by attaching a rubber outlet pipe 8 to the cylindrical casing 3. Here is the exit pipe 8
It is preferable that the starting end 8a of the rubber cylindrical hollow part 1 be extended by a certain length to improve sound attenuation characteristics.

A rubber partition wall 4a is installed horizontally within the rubber cylindrical hollow portion 1. The partition wall 4a is for dividing the rubber cylindrical hollow part 1 into a plurality of sections s1 and s2, and it can be provided as one to form two partitions as in this example, or it can be provided in plural to form a large number of partitions. You are free to do whatever you want. A relatively small-diameter through hole 9 is formed at the center of each partition wall 4a, and the dimensions of this hole 9 depend on the flow rate and condition of the gas flowing in from the exhaust inlet 5. The partition wall 4a of this example is integrally formed with the cylindrical joint 4 in order to simplify the structure.

Numerals 10a and 10b are drum-shaped hollow cores disposed near the partition wall 4a in each of the sections s1 and s2, and both have their main bodies made of rubber such as chloroprene. Each of the hollow cores 10a, 10b has a sound wave diffusing surface with a sharp protrusion p formed in the center on its front and rear surfaces, and a large number of small diameter through holes communicating with the core hollow part 11 at the wave-shaped top and bottom. 12 are formed. In this case, when the diameter of the through hole 12 is d, it is preferable for the mutual distance D between the through holes 12 adjacent in the circumferential direction to be at least 2×d if possible for the sake of sound deadening effect.
Furthermore, each core hollow part 11 is made of a relatively hard partition plate 1.
3, and each chamber r formed by this is filled with a sound absorbing material 14 such as glass fiber. Note that the partition plate 13 has hollow cores 10a, 1
It may be integrally molded from the same material as 0b, or it may be embedded with a hard plate made of a different material. Reference numeral 15 denotes support legs extending radially from the outer peripheral surfaces of the hollow cores 10a and 10b, and 16 is a rim connecting these legs, which is integrally molded with the hollow cores as in this example. Manufacturing becomes easier. The rim 16 is clamped at the front and rear by the cylindrical casing 2 or 3 and the cylindrical joint 4 to position the hollow core 10a or 10b. 17 is the rim 16 and the hollow core 10a or 10b
It is a gas passage formed between the surrounding area and the surrounding area.

Next, examples of use and effects of the above-mentioned product of the present invention will be explained. Figure 3 shows a medical oxygen concentrator M, which continuously compresses atmospheric air with an air compressor C, increases the oxygen concentration with a processing device E, and then depressurizes and sends it out from the outlet o, which is used for oxygen inhalation. It is intended for use. In this case, e is a compressed air discharge line for releasing the compressed air compressed by the air compressor C into the atmosphere as necessary, and the pipe end of this line is equipped with a silencer, which is a product of the present invention.
The AS inlet pipe 6 is connected.

When compressed air flows in from the exhaust inlet 5, the compressed air rapidly expands at the outlet of the inlet pipe 5, thereby being expanded and muffled. Subsequently, the air becomes the hollow core 10a.
The sound wave is diffused in the radial direction by the sound wave diffusion surface in front of the
In addition, in this process, resonance is muffled through the hollow portion 11 of the hollow core 10a, the sound absorbing material 14, and the small diameter through hole 12. Furthermore, the air bends along the route indicated by arrows f1 and f2.
It reaches the rear part of the hollow core 10a, and reaches the center of the partition wall 4a while being resonated and muffled in the same manner as described above. The compressed air that has reached this point is blown out rearward from the through hole 9 of the partition wall 4a, so it expands and is muffled at the rear part of the partition wall 4a, and due to the presence of the next hollow core 10b, it is diffused on the sound wave diffusion surface in the same manner as described above. Resonance is muted. Furthermore, the compressed air follows a curved path in the directions of arrows f3 and f4 and reaches a position behind the hollow core 10b, where it is subjected to the same resonance silencing as described above by the hollow core 10b.
A silencing effect is also provided by the presence of the void n, and the sound is then released into the atmosphere through the outlet pipe 8.

Furthermore, in addition to the above-mentioned silencing effect, in the product of the present invention, the rubber walls of the cylindrical hollow part 1 and the hollow cores 10a and 10b function as diaphragms, so the vibrations of the compressed air that should be muffled propagate to these walls. This vibration promotes resonance silencing, and since sound is efficiently attenuated while being converted into thermal energy, the compressed air is more effectively subjected to the silencing effect over a wide range of frequencies.

In an experimental example conducted by the applicant, it was possible to reduce the noise level, which reached approximately 70 phons without a silencer, to approximately 40 phons by installing the silencer of the present invention.

(Effect of the invention) According to the invention as described above, since the partition wall 4a is provided in the cylindrical hollow part 1 and the predetermined hollow cores 10a, 10b are provided in each section s1, s2, it is possible to achieve expansion noise reduction and In addition to being able to effectively perform resonance silencing, etc., the cylindrical hollow part 1 and the hollow cores 10a, 1
Since the walls of 0b are made of rubber, these walls can function as a diaphragm, converting sound vibrations into thermal energy, and efficiently attenuating sound pressure over a wide range of frequencies, making it simple and compact. Although it has a simple configuration, it is possible to efficiently muffle noise caused by the release of compressed air.

[Brief explanation of drawings]

Figure 1 is a longitudinal sectional view of the product of the present invention, taken along the line X-X in Figure 2, and Figure 2 is a cross-sectional view taken along the line Y-Y in Figure 1.
A partial sectional view, FIG. 3, is a diagram of a medical oxygen concentrator using the product of the present invention. DESCRIPTION OF SYMBOLS 1... Cylindrical hollow part, 4a... Partition wall, 5... Exhaust inlet, 7... Exhaust outlet, 8... Outlet pipe, 8a...
... Starting end, 9 ... Through hole, 10a and 10b ... Hollow core, 11 ... Core hollow part, 12 ... Small diameter small hole, 13 ... Partition plate, 14 ... Sound absorbing material, p ... Sharp point Projection, r... chamber, s1 and s2... compartment.

Claims (1)

[Claims for Utility Model Registration] 1. An exhaust inlet 5 in the center of the front wall of the rubber cylindrical hollow part 1.
Then, a partition wall 4a is provided with an exhaust outlet 7 at the center of the wall, and a through hole 9 is opened at the center to divide the hollow part into a plurality of sections s1 and s2.
are installed horizontally inside the hollow portion, and each section includes a roughly drum-shaped rubber hollow core 10a, 1.
0b, each hollow core has a corrugated front and rear surface that forms a sound wave diffusing surface with a sharp protrusion p in the center, and a large number of holes at the top and bottom of the corrugation that lead to the core hollow part 11. Forming a small diameter through hole 12,
Moreover, the diaphragm silencer is characterized in that the hollow core is divided into two parts, front and rear, by a partition plate 13, and a sound absorbing material 14 is loaded into each chamber r. 2. The diaphragm muffler according to claim 1, wherein the starting end 8a of the outlet pipe 8 constituting the exhaust outlet 7 extends a certain length into the rubber cylindrical hollow part 1.