JP2007322577A - Sound isolation earflap - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound isolation earflap in which low frequency noise is highly efficiently reduced, while its maintenance is simple. <P>SOLUTION: The maintenance becomes simple, as operation power etc. is not needed by using and attaching a vibration suppression material composed of piezoelectric/dielectric/conductive materials, and organic polymeric materials matrix, to a main body 2 as a sound absorption material 1, and high sound isolation effect is obtained by efficiently reducing the low frequency noise by sound absorption material 1 composed of piezoelectric/dielectric/conductive materials in which the low frequency noise is reduced by vibration suppression, and organic polymeric materials matrix. Moreover, as a thickness of the sound absorption material 1 is reduced and not bulky, the ear pad is made small enough. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a soundproof ear pad that is provided in headphones or the like and covers a user's ear to prevent hearing loss due to noise.

  Conventionally, as a soundproof ear pad for covering a user's ear using a sound-absorbing material and preventing deafness due to noise, for example, an ear pad covering the ear is attached to both ends of the headband, and each ear pad is There has been disclosed a headphone-type silencer comprising a silencer element that includes a tubular body and restricts the passing frequency band of sound waves that pass in the axial direction (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 63-237097

  However, in the conventional soundproof earpiece as described in Patent Document 1, since a microphone is used as a silencer element, electric power is required as its power, and maintenance and management such as maintenance costs are complicated. It was something. In addition, if a sound absorbing material such as glass wool or rock wool is used as a noise-reducing element that does not use power, the thickness must be extremely large to reduce low-frequency noise, and it becomes too large for use as an ear pad. there were.

  The present invention has been made in view of the problems as described above, and is intended to provide a soundproof earpiece capable of reducing low-frequency noise with high efficiency while being easy to maintain.

  In order to achieve the above object, the present invention is configured as follows. That is, a soundproof ear pad according to the present invention includes a main body and a sound absorbing material that is attached to the main body and covers at least the periphery of the ear hole when worn, and the sound absorbing material is a piezoelectric / dielectric / conductive material and an organic polymer material matrix. The vibration-damping material consisting of the above is formed into a sheet shape.

  According to the soundproof ear pad according to the present invention, operation power and the like are not required, and maintenance and management are simple, but low frequency noise composed of a piezoelectric / dielectric / conductive material and an organic polymer material matrix is suppressed. By using the vibration damping material that can be reduced as a sound absorbing material, low frequency noise can be efficiently reduced and a high soundproofing effect can be obtained. Further, the thickness of the sound absorbing material is small and is not bulky, and can be sufficiently small as an ear pad.

  Here, the piezoelectric / dielectric / conductive material includes, as an antioxidant, a primary antioxidant such as a sulfur-based antioxidant, a phenol-based antioxidant, a phenol-based heat stabilizer, a stabilizer / antioxidant, Subsequent antioxidants, processing stabilizers, and the like may be used. Among them, Sumilizer (registered trademark), which is an antioxidant mainly composed of 4,4′-butylidenebis (3-methyl-6-t-butylphenol), is used. N, N′-dicyclohexyl-2-benzothiazolylsulfenamide and the like are preferable, and the molecular weight is preferably about 30 to 10,000. The organic polymer material matrix is a synthetic resin material such as chlorinated polyolefin, polyvinylidene chloride, fluorinated polyolefin, polyvinylidene fluoride, polyurethane, acrylic rubber, and preferably has a molecular weight of about 10,000 to 1,000,000. Polyethylene, and the molecular weight is preferably about 20,000 to 500,000. A damping material obtained by adding 5 to 80 parts by weight of the piezoelectric / dielectric / conductive material as described above to 100 parts by weight of the organic polymer material matrix is formed into a sheet shape and used as a sound absorbing material.

  The sound absorbing material contains 10 to 95% by weight of chlorinated polyethylene having a molecular weight of 10,000 to 1,000,000 as an organic polymer material matrix, and 5 to 80% by weight of a bisphenol antioxidant having a molecular weight of 30 to 10,000 as a piezoelectric / dielectric / conductive material. It is preferable that the low frequency noise can be more efficiently reduced.

  The mechanism by which such low-frequency noise is effectively reduced is not completely clear, but bisphenol-based antioxidants with a molecular weight in the above range are dispersed and distributed between chlorinated polyethylenes having a molecular weight in the above range. By doing so, the internal resistance is increased and the vibration damping property of the sheet-like sound absorbing material is improved, and the flexibility is secured by the chlorinated polyethylene having the molecular weight in the above range, so that the sheet-like sound absorbing material is smooth. It is mentioned that it can be deformed.

  As the bisphenol-based antioxidant, the above-mentioned 4-4′-butylidenebis (3-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2 '-Methylenebis (4-ethyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-t-butylphenol) and the like having a molecular weight of 30 to 10,000 can be used.

  According to the soundproof ear pad according to the present invention, operation power and the like are not required, and maintenance and management are simple, but low frequency noise composed of a piezoelectric / dielectric / conductive material and an organic polymer material matrix is suppressed. By using the vibration damping material that can be reduced as a sound absorbing material, low frequency noise can be efficiently reduced and a high soundproofing effect can be obtained. Further, the thickness of the sound absorbing material is small and is not bulky, and can be sufficiently small as an ear pad.

  BEST MODE FOR CARRYING OUT THE INVENTION The best embodiment according to the present invention will be specifically described below with reference to the drawings.

  1A and 1B show an embodiment of a soundproof ear pad according to the present invention. FIG. 1A is a front view showing a state worn by a user, and FIG. 1B is a longitudinal sectional view of the soundproof ear pad. . The soundproof ear pad 10 covers both ears of the user M, and the soundproof ear pad 10 covering both ears is made of metal and has an elastic force so as to press the soundproof ear pad 10 against the user's ear. It is connected by the connecting material 20 and has a headphone shape.

  (B) is AA sectional drawing in (a). The soundproof ear pad 10 is attached to a space in the main body 2 in a state where the sound absorbing material 1 is tensioned by a mounting portion 21 provided on the inner surface of the main body 2. The opposite side of the main body 2 from the direction α in which the noise comes is opened, and the user's M earlobe is accommodated in this opening portion when worn, so that the main body 2 covers the entire ear of the user M. The sound absorbing material 1 covers the periphery of the ear hole. When noise arrives at the soundproof ear pad 10 from the direction α, the noise transmitted through the main body 2 reaches the sound absorbing material 1, but the sound absorbing material 1 is made of a piezoelectric / dielectric / conductive material and an organic polymer material matrix. By forming the vibration material into a sheet shape, the sound-absorbing material 1 vibrates and noise is reduced, and the degree of reaching the user's M ear is reduced, thereby preventing hearing loss.

  Here, the sound-absorbing material 1 is tensioned and attached in the main body 2, vibrates against noise, and the sound is absorbed by the vibration being attenuated mainly by the internal resistance of the sound-absorbing material 1. Therefore, both sides of the sound absorbing material 1 can be spaced apart from the inner surface of the main body 2 and the user's M earlobe so that the sound absorbing material 1 can vibrate. The sound-absorbing material 1 due to such vibration attenuation can particularly effectively reduce low-frequency noise.

  In the present embodiment, the soundproof ear pad 10 is connected by the connecting material 20 to form a headphone shape, but the shape is particularly limited as long as the sound absorbing material 1 can cover the periphery of the ear hole of the user M. Instead, a shape that can be clipped directly to the earlobe or a size that can be further miniaturized so that it can be fitted into the entrance of the user's M ear hole.

  Although the sound-absorbing material 1 in the above-described embodiment is a sheet-like material, the thickness is preferably about 1 to 20 mm. If the thickness is less than 1 mm, the low-frequency vibration is not sufficiently suppressed. If the thickness is more than 20 mm, the low-frequency vibration suppression effect accompanying the increase in the thickness of the sound absorbing material 1 will reach its peak and the cost performance will be significantly reduced. Will be.

  The sound absorbing material 1 reduces low-frequency noise, but is reduced by changing the blending ratio of the piezoelectric / dielectric / conductive material and the organic polymer material matrix, the material to be selected, and the molecular weight of each. It is possible to selectively reduce the frequency of low-frequency noise and reduce only the noise that needs to be reduced. By utilizing such a characteristic, for example, in a soundproof ear pad used by a worker in a factory, a low frequency noise around 100 Hz is selectively reduced with high efficiency and a sound wave characteristic around 200 Hz is not reduced so much. By doing so, it is possible to prevent hearing loss by reducing only low-frequency noise that is around 100 Hz from factory equipment, and not to reduce sound waves around 200 Hz, which is mainly the frequency of human speech. Even though the noise of the equipment can be reduced, humans can talk with each other through the provided partition walls, improving convenience and improving safety without disturbing the voice calling for help in the event of an accident. be able to.

It is explanatory drawing which shows one Embodiment of the soundproof ear pad concerning this invention.

Explanation of symbols

1 Sound absorbing material 2 Body 10 Soundproof ear pad

Claims (2)

A main body and a sound absorbing material that is attached to the main body and covers at least the periphery of the ear hole when worn, and the sound absorbing material is formed into a sheet-like vibration damping material comprising a piezoelectric / dielectric / conductive material and an organic polymer material matrix A soundproof ear pad characterized by being made. The sound absorbing material includes 10 to 95% by weight of chlorinated polyethylene having a molecular weight of 10,000 to 1,000,000 as an organic polymer material matrix, and 5 to 80% by weight of a bisphenol antioxidant having a molecular weight of 30 to 10,000 as a piezoelectric / dielectric / conductive material. The soundproof ear pad according to claim 1, wherein

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