WO2022168533A1 - 消音構造体および消音システム - Google Patents
消音構造体および消音システム Download PDFInfo
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- WO2022168533A1 WO2022168533A1 PCT/JP2022/000504 JP2022000504W WO2022168533A1 WO 2022168533 A1 WO2022168533 A1 WO 2022168533A1 JP 2022000504 W JP2022000504 W JP 2022000504W WO 2022168533 A1 WO2022168533 A1 WO 2022168533A1
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- sound deadening
- cross
- opening
- cavity
- tubular member
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Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/242—Sound-absorbing material
Definitions
- the present invention relates to a sound deadening structure and a sound deadening system.
- a porous sound absorbing material made of urethane, polyethylene, or the like is installed in the ventilation sleeve.
- porous sound absorbing materials such as urethane and polyethylene are used, the absorption rate of low-frequency sounds of 1000 Hz or less is extremely low, so it is necessary to increase the volume in order to increase the absorption rate.
- a resonance muffler that muffles sounds near the resonance frequency of the muffler has also been proposed.
- a resonance type muffler at least a quarter of the wavelength of the resonance frequency is required, which increases the size of the muffler. Therefore, there is a problem that it is difficult to achieve both high air permeability and soundproof performance.
- resonance mufflers muffle sounds of specific frequencies. Therefore, the resonance to be silenced is limited to only one frequency, and since the frequency band that is silenced by the resonance muffler is narrow, there is a problem that the resonance of other frequencies cannot be silenced.
- a muffler capable of silencing a wide range of frequencies including low frequencies
- a muffler has been proposed that has a cavity and an opening that communicates the cavity and the ventilation sleeve, and that muffles noise without using resonance. ing.
- Patent Document 1 discloses a sound deadening system in which a ventilation sleeve installed through a wall is provided with a muffler for muffling the sound passing through the ventilation sleeve, wherein the muffler is generated inside the ventilation sleeve.
- the muffler has a cavity and an opening that communicates the cavity and the outside, and is arranged on one end face side of the wall.
- the muffler does not resonate with the sound of the first resonance frequency generated in the ventilation sleeve, and the sound of the first resonance frequency is A sound deadening system is described that does not mute by resonance, but by a sound absorbing material.
- a muffler that has a cavity and an opening that connects the cavity and the ventilation sleeve and that muffles noise without using resonance is required to have a higher low-frequency sound absorption coefficient.
- An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a sound deadening structure and a sound deadening system with a high sound absorption coefficient in the low frequency region.
- the present invention has the following configurations.
- a sound deadening structure installed on a tubular member,
- the sound deadening structure has a cavity, an opening that communicates between the cavity and the tubular member, and a closing part that closes the cavity at a position facing the opening,
- the sound deadening structure according to [1] wherein at least one of the angles formed by line segments contacting vertices of the hollow portion that are not contacting the opening is greater than ⁇ /2 [rad].
- a sound deadening system in which the sound deadening structure according to any one of [1] to [6] is installed in a tubular member A sound deadening system having two or more sound deadening structures made up of parts of the same shape.
- a sound deadening system in which the sound deadening structure according to any one of [1] to [6] is installed in a tubular member,
- the muffling structure is a muffling system that does not block 50% or more of the cross-sectional area perpendicular to the axial direction of the tubular member.
- FIG. 1 is a sectional view conceptually showing an example of a sound deadening system having a sound deadening structure of the present invention
- FIG. FIG. 2 is a cross-sectional view taken along line bb of FIG. 1
- FIG. 2 is a perspective view of the sound deadening structure shown in FIG. 1
- FIG. 4 is a perspective view showing another example of the sound deadening structure of the present invention
- FIG. 2 is a cross-sectional view conceptually showing a sound deadening system having another example of the sound deadening structure of the present invention
- FIG. 6 is a cross-sectional view taken along line cc of FIG. 5
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure;
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure;
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure;
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure;
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure;
- FIG. 10 is a conceptual diagram for explaining the shape of another example of the muffling structure; It is a figure for demonstrating the structure of the conventional muffler. It is a figure for demonstrating the structure of the muffling structure of this invention.
- FIG. 10 is a diagram for explaining another function of the sound deadening structure of the present invention
- FIG. 4 is a conceptual diagram for explaining the action when producing a sound deadening structure
- FIG. 10 is a diagram for explaining another function of the sound deadening structure of the present invention
- FIG. 4 is a conceptual diagram showing an example of another configuration of the muffling structure of the present invention
- FIG. 22 is an exploded view of the muffling structure shown in FIG. 21
- FIG. 22 is a conceptual diagram showing a state during transportation of parts constituting the sound deadening structure shown in FIG. 21;
- FIG. 4 is a perspective view conceptually showing another example of the sound deadening structure of the present invention. It is a figure showing the board member which does not have a rib structure.
- FIG. 26 is a conceptual diagram of graphs of sound pressure and sound insulation characteristics for explaining the resonance frequency of the plate member shown in FIG. 25; It is a figure showing the board member which has a rib structure.
- FIG. 28 is a conceptual diagram of graphs of sound pressure and sound insulation characteristics for explaining the resonance frequency of the plate member shown in FIG. 27; It is a figure for demonstrating the measuring method of the transmission loss by a board member. It is a graph showing the relationship between frequency and transmission loss.
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention.
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention
- FIG. 5 is a diagram conceptually showing another example of the rib structure of the sound deadening structure of the present invention
- It is a figure for demonstrating the calculation model of the muffling system in an Example. It is a graph showing the relationship between frequency and transmission loss. It is a graph showing changes in frequency and transmission loss.
- a numerical range represented by "-" means a range including the numerical values before and after "-" as lower and upper limits.
- the terms “perpendicular” and “parallel” include the range of error that is permissible in the technical field to which the present invention belongs. For example, “perpendicular” and “parallel” means within a range of less than ⁇ 10° with respect to strict perpendicularity or parallelism, and the error with respect to strict perpendicularity or parallelism is 5° or less is preferable, and 3° or less is more preferable.
- the terms “same” and “same” shall include the margin of error generally accepted in the technical field.
- the muffling structure of the present invention is A sound deadening structure installed on a tubular member,
- the sound deadening structure has a cavity, an opening that communicates between the cavity and the tubular member, and a closing part that closes the cavity at a position facing the opening,
- the cross-sectional area of the hollow portion on the opening side is larger than the cross-sectional area of the hollow portion on the closing portion side.
- a muffling system of the present invention is a muffling system in which the above muffling structure is installed in a tubular member.
- the installed sound deadening structure does not occupy 50% or more of the cross-sectional area perpendicular to the axial direction of the tubular member.
- FIG. 1 is a schematic cross-sectional view showing an embodiment of a sound deadening system having a sound deadening structure of the present invention.
- FIG. 2 is a cross-sectional view taken along line bb of FIG. 3 is a perspective view of the sound deadening structure of FIG. 1.
- FIG. 1 is a cross section parallel to the axial direction of the central axis Ix of the tubular member 12 and passing through the center of the connection hole 12a (opening 32).
- this cross section is also referred to as a "cross section”.
- FIG. 2 is a cross section perpendicular to the axial direction of the central axis Ix of the tubular member 12.
- this cross section is also referred to as a "front cross section”.
- the axial direction of the central axis Ix of the tubular member 12 is also simply referred to as the "axial direction”.
- the sound deadening system 10 has a cylindrical tubular member 12 and a sound deadening structure 22 arranged around the outer circumference of the tubular member 12 .
- the sound deadening structure 22 has a hollow portion 30, an opening portion 32, and a closed portion 34, and may muffle sound by causing Helmholtz resonance or air column resonance. It may be one that converts sound energy into heat energy to muffle the sound.
- Tubular member 12 is, for example, a ventilation sleeve such as a vent and an air conditioning duct.
- the tubular member 12 is not limited to a ventilation port, an air-conditioning duct, or the like, and may be a general duct used for various types of equipment.
- the walls of houses such as condominiums are composed of, for example, concrete walls, gypsum boards, heat insulating materials, veneers, wallpaper, etc., and ventilation sleeves are provided through these. .
- the sound deadening structure of the present invention can be suitably applied to such wall ventilation sleeves.
- the cross-sectional shape of the ventilation sleeve is not limited to a circular shape, and may be various shapes such as a square shape and a triangular shape.
- the cross-sectional shape of the ventilation sleeve may not be uniform in the axial direction of the central axis of the ventilation sleeve. That is, in the axial direction the diameter of the ventilation sleeve may vary. In the case of a ventilation sleeve for housing, the diameter of the ventilation sleeve (equivalent circle diameter) is about 70 mm to 160 mm.
- the average inner diameter (weighted average) of the ventilation sleeve may be about 70 mm to 160 mm.
- the inner diameter of the ventilation sleeve is measured with a resolution of 1 mm. If the cross-sectional shape of the sleeve is not circular, the inner diameter is obtained by converting the area into a diameter equivalent to a circle. If it has a fine structure such as unevenness of less than 1 mm, it is averaged.
- connection hole 12a is formed in a part of the outer peripheral surface of the tubular member 12, penetrating from the inside to the outside of the tubular member 12. As shown in FIG. In the illustrated example, the size of the connection hole 12a is substantially the same as the size of the opening 32 of the sound deadening structure 22, which will be described later.
- the sound deadening structure 22 has an outer shape of a substantially truncated quadrangular pyramid, has a cavity 30 inside, and has an opening 32 formed by opening the bottom of the truncated quadrangular pyramid. Also, the surface facing the opening 32 is closed to form a closed portion 34 .
- the hollow portion 30 is formed in a shape substantially similar to the outer shape of the sound deadening structure 22 . That is, the hollow portion 30 is substantially in the shape of a truncated quadrangular pyramid.
- the two surfaces (31a, 31b) facing in the axial direction are It is inclined with respect to a line segment perpendicular to the central axis Ix of the tubular member 12 when it is closed.
- the remaining two surfaces (31c, 31d) of the surfaces in contact with the opening 32 of the sound deadening structure 22 are, when viewed in front cross section, from the center of the tubular member 12, It is slanted with respect to a vertical line drawn down on the surface of the sound deadening structure 22 on the closed portion side.
- the sound deadening structure 22 is arranged on the outer peripheral surface of the tubular member 12 with the opening 32 aligned with the connection hole 12a of the tubular member 12 . Therefore, the bottom of the sound deadening structure 22 (the surface on the opening 32 side) is a curved surface along the outer peripheral surface of the tubular member 12 .
- the width of the cavity 30 narrows as the distance from the opening 32 increases. That is, the width W1 of the hollow portion 30 on the opening portion 32 side is wider than the width W2 on the closing portion 34 side, and gradually narrows toward the closing portion 34 side.
- the width of the cavity 30 narrows as the distance from the opening 32 increases. That is, the width W3 of the hollow portion 30 on the opening portion 32 side is wider than the width W4 on the closing portion 34 side, and gradually narrows toward the closing portion 34 side.
- the cross-sectional area of the hollow portion 30 on the opening portion 32 side is larger than the cross-sectional area of the hollow portion 30 on the closing portion 34 side.
- the cross-sectional area of the hollow portion 30 on the side of the opening 32 is determined when the cross-sectional shape of the tubular member 12 is circular or the like and the surface of the sound deadening structure on the side of the opening 30 is curved.
- the cross-sectional area of the cavity 30 on the plane tangential to the tubular member 12 at the center position of the opening 32 is defined as the cross-sectional area of the cavity 30 on the side of the opening 32 . Therefore, the width W 3 of the cavity 30 on the opening 32 side is the width of the cavity 30 on the tangential line to the tubular member 12 at the central position of the opening 32 .
- cross-sectional area of the hollow portion 30 on the closing portion 34 side is the cross-sectional area of the hollow portion 30 closest to the closing portion 34 side parallel to the plane of the cross-sectional area of the hollow portion 30 on the opening portion 32 side.
- the opening 32 is narrowed (narrower than the width of the cavity 30), such as when the opening 32 is partially blocked by the air volume adjustment member 20.
- the cross-sectional area of the cavity 30 closest to the opening 32 is the cross-sectional area of the cavity 30 on the opening 32 side.
- the sound deadening structure of the present invention has a hollow portion in at least one of a cross section (front cross section) perpendicular to the axial direction of the tubular member 12 and a cross section (cross cross section) parallel to the axial direction of the tubular member 12.
- the mechanism of the effect of increasing the sound absorption coefficient in the low frequency range is presumed as follows.
- the sound deadening system 10 has one sound deadening structure 22, but is not limited to this, and may have two or more sound deadening structures 22.
- each sound deadening structure 22 may be arranged at different positions in the circumferential direction of the tubular member 12 (hereinafter also simply referred to as the circumferential direction). However, they may be arranged at different axial positions of the tubular member 12 .
- the sound deadening structure 22 is arranged on the outer peripheral surface of the tubular member 12. There is no limitation to this as long as it is arranged in a position where it can muffle the sound it makes.
- the sound deadening structure 22 may be located near the end face of the tubular member 12 .
- sound deadening structure 22 may be located inside tubular member 12 .
- FIG. 5 shows a cross-sectional view conceptually showing another example of the noise reduction system of the present invention.
- FIG. 6 shows a cc sectional view of FIG.
- the muffling system 10b shown in FIGS. 5 and 6 has a tubular member 12 and two muffling structures 22 arranged at a position extending from the outer peripheral portion of the tubular member 12 on one end face side of the tubular member 12.
- the sound deadening system 10b includes a sound insulation hood 18 arranged on the end face of the tubular member 12 opposite to the end face on which the sound deadening structure 22 is arranged, and the sound deadening structure 22 of the tubular member 12 and an air volume adjusting member 20 arranged at a position passing through the central axis Ix of the tubular member 12 .
- the sound deadening structure 22 also has a porous sound absorbing material 24 inside the cavity 30 .
- the soundproof hood 18 is a conventionally known louver, louver, or the like that is installed in ventilation openings, air-conditioning ducts, and the like. Further, the air volume adjusting member 20 is a conventionally known register or the like.
- the two sound deadening structures 22 are arranged at the same position in the axial direction and at different positions in the circumferential direction (positions shifted by 180°).
- the two sound deadening structures 22 are formed as a part of two truncated conical parts (23a, 23b) whose bottom surfaces are put together to form a space inside. ing.
- One part 23 a forms one sound deadening structure 22 and the other part 23 b forms the other sound deadening structure 22 .
- the width of the edge of the two parts (23a, 23b) in contact with the other part is equal to or larger than the diameter of the tubular member 12 in the front cross section.
- Semicircular cutouts (25a, 25b) having substantially the same diameter as the diameter of the tubular member 12 are provided at the ends of the surfaces of the two parts (23a, 23b) on the side of the tubular member 12 that are in contact with the other part. ) is formed.
- an opening 26 having approximately the same diameter as the tubular member 12 is formed at a position through which the central axis Ix of the tubular member 12 passes when the two parts (23a, 23b) are assembled.
- the opening 26 is connected to one end face of the tubular member 12 and communicates with the inside of the tubular member 12 .
- the ends of the two parts (23a, 23b) on the side opposite to the tubular member 12 and in contact with the other part each have a semicircular shape for fitting the air volume adjustment member 20.
- a notch is formed to form an opening into which the air volume adjusting member 20 is fitted when the two parts (23a, 23b) are combined.
- the soundproof hood 18, the tubular member 12, the two parts (23a, 23b), and the air volume adjustment member 20 are brought into communication with each other, so that the soundproof hood 18 side and the air volume adjustment member 20 side can be ventilated. . That is, the two parts (23a, 23b) also function as part of the tubular member.
- the width of the cavity 30 narrows as the distance from the opening 32 increases. That is, the width W 1 of the hollow portion 30 on the opening 32 side is wider than the width W 2 of the closing portion 34 and gradually narrows toward the closing portion 34 side.
- the width of the cavity 30 narrows as the distance from the opening 32 increases. That is, the width W3 of the hollow portion 30 on the opening portion 32 side is wider than the width W4 on the closing portion 34 side, and gradually narrows toward the closing portion 34 side.
- the cross-sectional area of the hollow portion 30 on the opening portion 32 side is larger than the cross-sectional area of the hollow portion 30 on the closing portion 34 side.
- the sound absorption coefficient in the low frequency range can be increased without increasing the volume of the sound deadening structure.
- the width of the cavity 30 may be narrowed as the distance from the opening 32 increases.
- the shape of the sound deadening structure 22 may be a substantially truncated cone shape, a polygonal truncated pyramid shape, or the like.
- the side surfaces may be outwardly convex curved surfaces or outwardly concave curved surfaces.
- the shape of the sound deadening structure 22 may be such that one of the sides of a trapezoidal quadrangular prism is an opening.
- the shape of the sound deadening structure 22 is such that, as shown in FIG. As shown in FIG. 8, the shape may be a trapezoid in which the surface 31c is inclined and the surface 31d is not inclined.
- 7, like FIG. 5, is a diagram schematically showing the cross-sectional shape when two noise-absorbing structures 22 are provided, and FIG. 8, like FIG. 6, two noise-absorbing structures It is a figure which represents typically the shape of the front cross section in the case of having 22. FIG. The same applies to FIGS. 9 to 12 as well.
- the surface 31c is inclined and the surface 31d is trapezoidal, but the trapezoidal shape may be such that the surface 31d is inclined and the surface 31c is not inclined.
- the width of the cavity narrows as the distance from the opening increases.
- the shape of the sound deadening structure 22 is such that, as shown in FIG. As shown in FIG. 9, a trapezoidal shape in which the surfaces 31c and 31d are inclined may be used.
- a trapezoidal shape in which the surfaces 31c and 31d are inclined may be used in this example, in a cross section (front cross section) perpendicular to the axial direction of the tubular member.
- the inclination angle ⁇ 1 of the surface 31c and the inclination angle ⁇ 2 of the surface 31d may be the same or different.
- the shape of the sound deadening structure 22 is such that, as shown in FIG.
- the shape may be a rectangular shape in which the surfaces 31c and 31d are not inclined as shown in FIG.
- the surface 31a is slanted and the surface 31b is not slanted in a trapezoidal shape, but the surface 31b may be slanted and the surface 31a is not slanted.
- the width of the cavity narrows as the distance from the opening increases.
- the shape of the sound deadening structure 22 is such that, as shown in FIG. As shown in FIG. 11, the surfaces 31c and 31d may have a non-inclined rectangular shape.
- the width of the cavity narrows as the distance from the opening increases.
- the inclination angle ⁇ 3 of the surface 31a and the inclination angle ⁇ 4 of the surface 31b may be the same or different.
- the shape of the front cross section of the sound deadening structure 22 may be an annular shape (doughnut shape), as shown in FIG.
- the shape of the cross section may be a trapezoid in which the surface 31a is inclined and the surface 31b is not inclined as shown in FIG. may have a trapezoidal shape with an inclination.
- the width of the cavity narrows as the distance from the opening increases.
- the hollow portion in at least one of a cross section (front cross section) perpendicular to the axial direction of the tubular member and a cross section (cross cross section) parallel to the axial direction of the tubular member, the hollow portion is Since the width narrows as the distance from the opening increases, as shown in FIG. ⁇ /2 [rad]).
- At least one of the angles formed by the line segments contacting the vertices of the cavity that are not in contact with the opening is greater than 90°. Therefore, as shown in FIG. 17, dirt, mold, and the like are less likely to accumulate in the corners of the cavity that are not in contact with the opening. In addition, it is easy to remove the dirt, mold, and the like. In addition, it is difficult for moisture to accumulate in the corners, and the corners are easy to dry.
- the width of the cavity is At least one of the surfaces (31a to 31d) in contact with the opening is inclined. Therefore, as shown in FIG. 18, when the sound deadening structure 22 is produced using molds (Da, Db) such as injection molding, the slope of the surface in contact with the opening causes a draft angle. Therefore, it can be easily released from the mold after molding. In addition, since it can be properly manufactured by injection molding, it can be manufactured easily and at low cost compared to manufacturing by other processing methods such as cutting.
- the sound deadening structure of the present invention since at least one of the surfaces (31a to 31d) in contact with the opening is inclined, as shown in FIG. can be stacked. Therefore, the volume can be reduced at the time of transportation, etc., and transportation efficiency can be improved.
- the inclination angle ⁇ 1 of the surface 31c is considered to increase the sound absorption coefficient in the low-frequency region, facilitate mold release, improve transportation efficiency, and prevent dirt, mold, etc. from accumulating on the corners.
- the inclination angle ⁇ 2 of the surface 31d, and the total angle of the inclination angle ⁇ 3 of the surface 31a and the inclination angle ⁇ 4 of the surface 31b are preferably in the range of 0.1° to 20°, A range of 1° to 16° is more preferred, and a range of 2° to 12° is even more preferred.
- the area of the opening, the height of the cavity, etc. may be appropriately set according to the silencing mechanism of the silencing structure, the frequency band to be muted, and the like.
- the parts 23a and 23b can be separated (see FIG. 22) and superimposed as shown in FIG. Therefore, the volume can be reduced during transportation and the transportation efficiency can be improved. Moreover, when each muffling structure is composed of parts having the same shape, the mold can be shared, so that the cost can be reduced.
- At least two sound deadening structures are formed by one mold.
- the two sound deadening structures may have different shapes. Cost can be reduced by sharing a mold.
- FIG. 24 shows another example of the muffling structure of the present invention.
- the muffling structure 22b shown in FIG. 24 has a rib structure 36 on each of the surfaces (31a to 31d) adjacent to the opening.
- the parts that make up the sound deadening structure are not completely rigid bodies, for example, one surface that makes up the sound deadening structure may vibrate and transmit sound.
- one surface that makes up the sound deadening structure may vibrate and transmit sound.
- the resonance frequency of the parts constituting the sound deadening structure is increased, and the sound absorption in the low frequency region is improved. can be improved.
- FIG. 25 is a flat plate 80 without rib structure. As shown in FIG. 29, such a plate 80 is arranged inside a tubular member F, and when a sound wave is incident from one end of the tubular member F and the sound pressure is measured at the other end, As schematically shown in the upper graph of FIG. 26, the sound pressure increases at the resonance frequency f0 of the plate 80, and decreases as the distance from the resonance frequency f0 increases. That is, as schematically shown in the lower graph of FIG. 26, the sound insulation property of the plate 80 becomes low at the resonance frequency f 0 .
- the resonance frequency of the plate 81 shifts to the high frequency side, as schematically shown in the upper graph of FIG. Therefore, the sound pressure increases at this frequency f 1 and decreases as the distance from this resonance frequency f 1 increases. That is, as schematically shown in the lower graph of FIG. 28, the sound insulation properties of the plate 81 are lowered at the resonance frequency f 1 higher than the resonance frequency f 0 of the flat plate 80 . At this time, since the sound insulation property improves as the distance from the resonance frequency increases, the plate 81 provided with the rib structure 36 has higher sound insulation property in the low frequency region.
- the resonance frequency of the parts constituting the sound deadening structure is raised to improve the sound absorption in the low frequency region. be able to.
- FIG. 30 shows a graph obtained by obtaining the relationship between frequency and transmission loss by changing the height of the rib structure using the calculation model having the configuration shown in FIG.
- the tubular member F has an opening area of 10 cm ⁇ 10 cm and a length of 30 cm.
- the plate 81 had a size of 10 cm ⁇ 10 cm and a thickness of 2 mm.
- Rib height H was calculated at 0 mm, 2 mm, 3 mm, and 5 mm.
- the simulation used the acoustic module of the finite element method calculation software COMSOL ver5.5 (COMSOL).
- the rib structure is arranged so as to extend in the height direction of the surface adjacent to the opening. may be arranged so as to extend in the width direction, or may be arranged obliquely.
- one rib structure is provided on each surface adjacent to the opening, but this is not a limitation, and a plurality of rib structures are provided on each surface. good too.
- the rib structure has a linear shape, but is not limited to this.
- the rib structure may be a branched structure.
- the rib structure may be curvilinear.
- it may be corrugated.
- it may be bent in the middle.
- it may have a triangular wave shape.
- the shape, position, number, etc. of the rib structure may be the same or different for each surface.
- Materials for forming the sound deadening structure include metal materials, resin materials, reinforced plastic materials, and carbon fibers.
- metal materials include metal materials such as aluminum, titanium, magnesium, tungsten, iron, steel, chromium, chromium molybdenum, nichrome molybdenum, and alloys thereof.
- resin materials include acrylic resin, polymethyl methacrylate, polycarbonate, polyamideoid, polyarylate, polyetherimide, polyacetal, polyether ether ketone, polyphenylene sulfide, polysulfone, polyethylene terephthalate, polybutylene terephthalate, Resin materials such as polyimide and triacetyl cellulose can be used.
- reinforced plastic materials include carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP).
- the density of the members constituting the sound deadening structure is preferably 0.5 g/cm 3 to 2.5 g/cm 3 .
- the sound deadening structure of the present invention may have a porous sound absorbing material inside the cavity.
- the porous sound absorbing material is not particularly limited, and conventionally known sound absorbing materials can be used as appropriate.
- conventionally known sound absorbing materials can be used as appropriate.
- urethane foam, soft urethane foam, wood, sintered ceramic particles, phenolic foam, and other foam materials and materials containing microscopic air glass wool, rock wool, microfiber (thinsulate manufactured by 3M, etc.), floor mats, carpets , meltblown nonwoven fabrics, metal nonwoven fabrics, polyester nonwoven fabrics, metal wool, felt, insulation boards and glass nonwoven fabrics; fiber and nonwoven materials; wood wool cement boards; nanofiber materials such as silica nanofibers; Sound absorbing material is available.
- the placement of the muffling structure with respect to the tubular member is not particularly limited as long as it is a position that can properly muffle the sound. It is preferable to arrange so that 50% or more of the cross-sectional area perpendicular to is not blocked. Thereby, the air permeability of the tubular member can be ensured.
- the sound deadening structure of the present invention may have other commercially available soundproof members.
- the muffler of the present invention may have an insertion type muffler installed inside the ventilation sleeve, or may have an outdoor muffler installed at the end of the ventilation sleeve. good. By combining with other soundproofing materials, high soundproofing performance can be obtained in a wider band.
- Simulation 1 As simulation 1, as shown in FIG. 37, a simulation was performed for a structure in which two sound-absorbing structures 22 were arranged on the outer peripheral surface of tubular member 12 . In addition, a porous sound absorbing material 24 is arranged in the hollow portion of the sound deadening structure 22 .
- a soundproof hood 18 is arranged on the opening surface of the tubular member 12 opposite to the side on which the sound deadening structure 22 is installed, and a register (air volume adjustment member) is arranged.
- the soundproof hood is modeled on the soundproof hood (BON-TS) manufactured by Silfer Co., Ltd.
- the register is modeled after Unix Co., Ltd.'s register (KRP-BWF).
- the tubular member 12 had an inner diameter of 100 mm and a length of 300 mm.
- the height of the hollow portion of the sound deadening structure 22 from the inner diameter of the tubular member 12 was set to 220 mm.
- the porous sound absorbing material 24 is assumed to fill the entire cavity 30 .
- the flow resistance of the porous sound absorbing material 24 was set to 2650 [Pa ⁇ s/m 2 ].
- the diameter of the portion of the resistor inserted into the muffling structure was 150 mm.
- the cross section of the sound deadening structure 22 is a rectangular shape in which the surfaces 31a and 31b are not inclined, and as shown in FIG. is not inclined, the inclination angle ⁇ 1 of the surface 31c is changed to 0°, 2°, 6° and 10°.
- the case where the tilt angle ⁇ 1 is 0° is the comparative example, and the cases where the tilt angle ⁇ 1 is 2°, 6° and 10° are the examples.
- the width of the hollow portion in the cross section is 86 mm
- the width of the hollow portion in the front cross section is 251 mm when the inclination angle ⁇ 1 of the surface 31c is 0°
- the width of the cavity (opening) was adjusted so that the volume of the cavity was constant.
- the width W 3 of the cavity on the opening side is 253 mm and the cross-sectional area is 21578 mm 2
- the width W 4 on the closed side is 246.5 mm and the cross-sectional area is 21199 mm 2 .
- the width W 3 of the cavity on the opening side is 258 mm and the cross-sectional area is 22188 mm 2
- the width W 4 on the closed side is 237.5 mm and the cross-sectional area is 20425 mm. was 2 .
- the width W 3 of the cavity on the opening side is 263.5 mm and the cross-sectional area is 22661 mm 2
- the width W 4 of the closed part is 229.5 mm and the cross-sectional area is 19737 mm. was 2 .
- a sound wave is incident from a hemispherical surface in one space, and the amplitude per unit volume of the sound wave reaching the hemispherical surface in the other space is obtained.
- the hemispherical surface is a hemispherical surface with a radius of 500 mm centered on the center position of the opening surface of the tubular member.
- the incident sound wave had an amplitude of 1 per unit volume.
- FIG. 38 The results are shown in FIG. 38 as a graph showing the relationship between frequency and transmission loss.
- FIG. 39 is a graph showing the amount of change in transmission loss when the tilt angle ⁇ 1 is 0°.
- the transmission loss increases compared to when the tilt angle ⁇ 1 is 0°. is doing. That is, it can be seen that the sound absorption in the low frequency region is improved.
- simulation 2 As simulation 2, as shown in FIG. 9, the front section of the sound deadening structure 22 has a shape in which the surface 31c is inclined at an angle ⁇ 1 and the surface 31d is inclined at an angle ⁇ 2 , and the inclination angles ⁇ 1 and ⁇ 2 are set. was changed to 0°, 2°, 6°, and 10°, respectively.
- the case where the inclination angles ⁇ 1 and ⁇ 2 are 0° is the comparative example, and the cases where the inclination angles ⁇ 1 and ⁇ 2 are 2°, 6° and 10° are the examples.
- the width of the cavity in the front cross section is 251 mm when the inclination angle ⁇ 1 of the surface 31c and the inclination angle ⁇ 2 of the surface 31d are 0 °.
- the width of the hollow portion was adjusted so that the volume of the portion was constant.
- the width W 3 of the cavity on the opening side is 255 mm and the cross-sectional area is 21930 mm 2
- the width W 4 on the closing side is 242 mm and the cross-sectional area is 20812 mm. was 2 .
- the width W 3 of the cavity on the opening side is 265 mm and the cross-sectional area is 22790 mm 2
- the width W 4 on the closed side is 224 mm and the cross-sectional area is 19264 mm.
- the width W 3 of the cavity on the opening side is 276 mm and the cross-sectional area is 23736 mm 2
- the width W 4 on the closing side is 208 mm and the cross-sectional area is 17888 mm. There were 2 .
- FIG. 40 The results are shown in FIG. 40 as a graph representing the relationship between frequency and transmission loss.
- FIG. 41 is a graph showing the amount of change in transmission loss when the tilt angles ⁇ 1 and ⁇ 2 are 0°.
- FIGS. 40 and 41 in the frequency band between 300 Hz and 1100 Hz, when the tilt angles ⁇ 1 and ⁇ 2 are 2° to 10°, when the tilt angles ⁇ 1 and ⁇ 2 are 0°
- the transmission loss is increased in comparison. That is, it can be seen that the sound absorption in the low frequency region is improved.
- Simulation 3 As simulation 3, the cross section of the sound deadening structure 22 is assumed to have a shape in which the surface 31a is inclined at an angle ⁇ 3 and the surface 31b is inclined at an angle ⁇ 4 as shown in FIG. As shown in FIG. 9, the surface 31c is inclined at an angle ⁇ 1 and the surface 31d is inclined at an angle ⁇ 2 , and the inclination angles ⁇ 1 to ⁇ 4 are 0°, 2°, 6°, and , and 10°, respectively, in the same manner as in Simulation 1. The case where the inclination angles ⁇ 1 to ⁇ 4 are 0° is the comparative example, and the cases where the inclination angles ⁇ 1 to ⁇ 4 are 2°, 6° and 10° are the examples.
- the width of the cavity in the cross section was set to 86 mm when the inclination angle ⁇ 3 of the surface 31a and the inclination angle ⁇ 4 of the surface 31b were 0°, and the inclination angles ⁇ 3 and ⁇ 4 were changed. At that time, the width W1 and the width W2 were adjusted so that the width at the central position in the height direction was constant. Similarly, the width of the cavity in the front cross section is 251 mm when the inclination angle ⁇ 1 of the surface 31c and the inclination angle ⁇ 2 of the surface 31d are 0°, and when the inclination angles ⁇ 1 and ⁇ 2 are changed, The width W3 and the width W4 were adjusted so that the width at the central position in the height direction was constant.
- the width W 1 of the opening side of the hollow portion in the cross section is 90 mm
- the width W 2 of the closing portion side is 77 mm
- the opening side of the hollow portion in the front cross section is 90 mm
- the width W 3 of the opening was 255 mm
- the width W 4 of the closed portion was 242 mm. Therefore, the cross-sectional area of the cavity on the opening side was 22950 mm 2 , and the cross-sectional area of the cavity on the closed side was 18634 mm 2 .
- the width W 1 on the opening side of the cavity in the cross section is 100 mm
- the width W 2 on the closing side is 59 mm
- the opening of the cavity in the front cross section The side width W 3 was 265 mm and the closure side width W 4 was 224 mm. Therefore, the cross-sectional area of the cavity on the opening side was 13216 mm 2 , and the cross-sectional area of the cavity on the closed side was 26500 mm 2 .
- the width W 1 of the opening side of the cavity in the cross section is 110 mm
- the width W 2 of the closing side is 42 mm
- the opening of the cavity in the front cross section The side width W 3 was 276 mm and the closure side width W 4 was 208 mm. Therefore, the cross-sectional area of the cavity on the opening side was 30360 mm 2 , and the cross-sectional area of the cavity on the closed side was 8736 mm 2 .
- FIG. 42 The results are shown in FIG. 42 as a graph showing the relationship between frequency and transmission loss.
- FIG. 43 is a graph showing the amount of change in transmission loss when the tilt angles ⁇ 1 and ⁇ 2 are 0°.
- FIGS. 42 and 43 in the frequency band between 400 Hz and 1200 Hz, when the tilt angles ⁇ 1 to ⁇ 4 are 2° to 10°, when the tilt angles ⁇ 1 to ⁇ 4 are 0°, The transmission loss is increased in comparison. That is, it can be seen that the sound absorption in the low frequency region is improved.
- Simulation 4 As simulation 4, the cross section of the sound deadening structure 22 is shown in FIG. 10, with the surface 31a inclined at an angle ⁇ 3 and the surface 31b not inclined, and the front cross section of the sound deadening structure 22 is shown in FIG. As shown, the simulation was performed in the same manner as Simulation 1, except that the surfaces 31c and 31d were not inclined and the angles of inclination ⁇ 3 were changed to 0°, 2°, 6°, and 10°, respectively. Carried out. The case where the tilt angle ⁇ 3 is 0° is the comparative example, and the cases where the tilt angle ⁇ 3 is 2°, 6°, and 10° are the examples.
- the width of the cavity in the cross section is set to 86 mm when the inclination angle ⁇ 3 of the surface 31a is 0°, and when the inclination angle ⁇ 3 is changed, the cavity has a constant volume.
- the width of the part (opening) was adjusted.
- the width of the cavity in the front cross section was 251 mm.
- the width W 1 of the cavity on the opening side is 88 mm and the cross-sectional area is 22088 mm 2
- the width W 2 on the closed side is 82 mm and the cross-sectional area is 20457 mm 2 .
- the width W 1 of the cavity on the opening side is 93 mm and the cross-sectional area is 23343 mm 2
- the width W 3 on the closed side is 72.5 mm and the cross-sectional area is 18198 mm 2 .
- Met When the inclination angle ⁇ 3 is 10°, the width W 1 of the cavity on the opening side is 98 mm, the cross-sectional area is 24,598 mm 2 , and the width W 2 on the closed side is 64 mm, and the cross-sectional area is 16,064 mm 2 . rice field.
- FIG. 44 The results are shown in FIG. 44 as a graph representing the relationship between frequency and transmission loss.
- FIG. 45 is a graph showing the amount of change in transmission loss when the tilt angle ⁇ 3 is 0°.
- the transmission loss increases compared to when the tilt angle ⁇ 3 is 0°. is doing. That is, it can be seen that the sound absorption in the low frequency region is improved.
- the width of the cavity in the cross section is 86 mm when the inclination angle ⁇ 3 of the surface 31a and the inclination angle ⁇ 4 of the surface 31b are 0°.
- the width of the cavity (opening) was adjusted so that the volume of the part was constant.
- the width of the cavity in the front cross section was 251 mm.
- the width W 1 of the cavity on the opening side is 90 mm and the cross-sectional area is 22590 mm 2
- the width W 2 on the closed side is 77 mm and the cross-sectional area is 19327 mm. was 2 .
- the width W 1 of the cavity on the opening side is 100 mm and the cross-sectional area is 25100 mm 2
- the width W 2 on the closed side is 59 mm and the cross-sectional area is 14809 mm. was 2 .
- the width W 1 of the cavity on the opening side is 110 mm and the cross-sectional area is 27610 mm 2
- the width W 2 on the closing side is 42 mm and the cross-sectional area is 10542 mm. was 2 .
- FIG. 46 The results are shown in FIG. 46 as a graph showing the relationship between frequency and transmission loss.
- FIG. 47 is a graph showing the amount of change in transmission loss when the tilt angles ⁇ 3 and ⁇ 4 are 0°.
- FIGS. 46 and 47 in the frequency band between 400 Hz and 800 Hz, when the tilt angles ⁇ 3 and ⁇ 4 are 2° to 10°, when the tilt angles ⁇ 3 and ⁇ 4 are 0°, The transmission loss is increased in comparison. That is, it can be seen that the sound absorption in the low frequency region is improved. From the above results, the effect of the present invention is clear.
- Reference Signs List 10 10b muffling system 12 tubular member 12a connecting hole 18 soundproof hood 20 air volume adjusting member 22, 22b muffling structure 23a, 23b part 24 porous sound absorbing material 25a, 25b notch 26 opening 30 cavity 31a to 31d surface 32 opening 36, 36b to 36g Rib structure 80, 81 Plate 122 Conventional muffler Ix Central axis of tubular member W1 Width of cavity on opening side in cross section W2 Width of cavity on closing side in cross section W3 Width of the cavity on the opening side in the front cross section W 4 Width of the cavity on the closing side in the front cross section ⁇ 1 to ⁇ 4 Inclination angles of the planes Da, Db Die D Dirt H Rib height
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Abstract
Description
しかしながら、ウレタンおよびポリエチレン等の多孔質吸音材を用いる場合には、1000Hz以下の低周波音の吸収率が極端に低くなるため、吸収率を大きくするためには体積を大きくすることが必要であるが、換気口、空調用ダクトなどの通気性を確保する必要があるため、多孔質吸音材の大きさには限度があり、高い通気性と防音性能とを両立することが難しいという問題があった。
[1] 管状部材に設置される消音構造体であって、
消音構造体は、空洞部、空洞部と管状部材とを連通する開口部、および、開口部と対面する位置で空洞部を閉塞する閉塞部を有し、
開口部側の空洞部の断面積が、閉塞部側の空洞部の断面積よりも大きい消音構造体。
[2] 空洞部の、開口部と接しない頂点に接する線分同士がなす角度の少なくとも1つが、π/2[rad]より大きい[1]に記載の消音構造体。
[3] 管状部材の軸方向に垂直な断面において、空洞部の幅が、開口部から離間するにしたがって狭くなっている[1]または[2]に記載の消音構造体。
[4] 消音構造体がリブ構造を有する[1]~[3]のいずれかに記載の消音構造体。
[5] 消音構造体を構成する部材の密度が0.5g/cm3~2.5g/cm3である[1]~[4]のいずれかに記載の消音構造体。
[6] 空洞部内に多孔質吸音材を有する[1]~[5]のいずれかに記載の消音構造体。
[7] [1]~[6]のいずれかに記載の消音構造体を管状部材に設置した消音システムであって、
同じ形状の部品からなる2以上の消音構造体を有する消音システム。
[8] [1]~[6]のいずれかに記載の消音構造体を管状部材に設置した消音システムであって、
2以上の消音構造体を有し、
少なくとも2つの消音構造体が1つの金型で形成されたものである消音システム。
[9] [1]~[6]のいずれかに記載の消音構造体を管状部材に設置した消音システムであって、
消音構造体は、管状部材の軸方向に垂直な断面積のうち、50%以上塞がない消音システム。
以下に記載する構成要件の説明は、本発明の代表的な実施態様に基づいてなされるが、本発明はそのような実施態様に限定されるものではない。
なお、本明細書において、「~」を用いて表される数値範囲は、「~」の前後に記載される数値を下限値および上限値として含む範囲を意味する。
また、本明細書において、「直交」および「平行」とは、本発明が属する技術分野において許容される誤差の範囲を含むものとする。例えば、「直交」および「平行」とは、厳密な直交あるいは平行に対して±10°未満の範囲内であることなどを意味し、厳密な直交あるいは平行に対しての誤差は、5°以下であることが好ましく、3°以下であることがより好ましい。
本明細書において、「同一」、「同じ」は、技術分野で一般的に許容される誤差範囲を含むものとする。
本発明の消音構造体は、
管状部材に設置される消音構造体であって、
消音構造体は、空洞部、空洞部と管状部材とを連通する開口部、および、開口部と対面する位置で空洞部を閉塞する閉塞部を有し、
開口部側の空洞部の断面積が、閉塞部側の空洞部の断面積よりも大きい消音構造体である。
本発明の消音システムは、上記消音構造体を管状部材に設置した消音システムである。
本発明の消音システムは、設置された消音構造体が、管状部材の軸方向に垂直な断面積のうち、50%以上塞がないことが好ましい
図1は、本発明の消音構造体を有する消音システムの実施態様の一例を示す模式的な断面図である。図2は、図1のb-b線断面図である。図3は、図1の消音構造体の斜視図である。具体的には、図1は、管状部材12の中心軸Ixの軸方向に平行で、接続孔12a(開口部32)の中心を通る断面である。以下、この断面を「横断面」ともいう。また、図2は、管状部材12の中心軸Ixの軸方向に垂直な断面である。以下、この断面を「正面断面」ともいう。また、管状部材12の中心軸Ixの軸方向を単に「軸方向」ともいう。
なお、管状部材12は、換気口および空調用ダクト等に限定はされず、各種機器に用いられる一般的なダクトであってもよい。
中でも、マンションのような住宅の壁は、例えば、コンクリート壁、石膏ボード、断熱材、化粧板、および、壁紙等を有して構成されており、これらを貫通して通気スリーブが設けられている。本発明の消音構造体は、このような壁の通気スリーブに好適に適用することができる。
また、住宅用の通気スリーブの場合には、通気スリーブの直径(円相当直径)は70mm~160mm程度である。また、軸方向において、通気スリーブの直径が変化する場合には、通気スリーブの平均内径(加重平均)が70mm~160mm程度であればよい。
なお、通気スリーブの内径は、分解能を1mmとして測定する。スリーブの断面形状が、円形ではない場合は、その面積を円相当面積として直径に換算して内径を求める。1mm未満の凹凸等の微細構造を有する場合には、これを平均化する。
開口部32側の空洞部30の断面積が大きい方が、開口部32付近の音響インピーダンスが低くなり、音波が消音構造体に侵入しやすいこと、および、回折特性が強い低周波でその効果が発生しやすいことから、低周波領域における吸音率をより高くできると推定される。ただし、多孔質吸音材の吸音効果は、低周波領域では弱くなるため、低周波領域の方が高周波領域よりも吸音効果が高いわけではない。
例えば、本発明における消音器以外に、通気スリーブの内部に設置する内挿型消音器を有していてもよいし、通気スリーブの端部に設置する野外設置型消音器を有していてもよい。
他の防音部材と組み合わせることで、より広い帯域で高い防音性能を得られる。
シミュレーション1として、図37に示すように、管状部材12の外周面に2つの消音構造体22を配置した構成についてシミュレーションを行なった。また、消音構造体22の空洞部内には多孔質吸音材24が配置される構成とした。
また、多孔質吸音材24は、空洞部30の全域に充填されるものとした。多孔質吸音材24の流れ抵抗は2650[Pa・s/m2]とした。
また、レジスターの消音構造体に挿入する部分の径は、150mmとした。
シミュレーション2として、消音構造体22の正面断面が図9に示すように、面31cが角度θ1で傾斜し、面31dが角度θ2で傾斜している形状として、傾斜角度θ1およびθ2を0°、2°、6°、および、10°にそれぞれ変更した以外はシミュレーション1と同様にしてシミュレーションを実施した。傾斜角度θ1およびθ2が0°の場合が比較例、傾斜角度θ1およびθ2が2°、6°、および、10°の場合が実施例である。
シミュレーション3として、消音構造体22の横断面が図12に示すように、面31aが角度θ3で傾斜し、面31bが角度θ4で傾斜している形状として、消音構造体22の正面断面が図9に示すように、面31cが角度θ1で傾斜し、面31dが角度θ2で傾斜している形状として、傾斜角度θ1~θ4を0°、2°、6°、および、10°にそれぞれ変更した以外はシミュレーション1と同様にしてシミュレーションを実施した。傾斜角度θ1~θ4が0°の場合が比較例、傾斜角度θ1~θ4が2°、6°、および、10°の場合が実施例である。
シミュレーション4として、消音構造体22の横断面が図10に示すように、面31aが角度θ3で傾斜し、面31bが傾斜していない形状として、消音構造体22の正面断面が図11に示すように、面31cおよび面31dが傾斜していない長方形状として、傾斜角度θ3を0°、2°、6°、および、10°にそれぞれ変更した以外はシミュレーション1と同様にしてシミュレーションを実施した。傾斜角度θ3が0°の場合が比較例、傾斜角度θ3が2°、6°、および、10°の場合が実施例である。
シミュレーション5として、消音構造体22の横断面が図12に示すように、面31aが角度θ3で傾斜し、面31bが角度θ4で傾斜している形状として、消音構造体22の正面断面が図11に示すように、面31cおよび面31dが傾斜していない長方形状として、傾斜角度θ3およびθ4を0°、2°、6°、および、10°にそれぞれ変更した以外はシミュレーション1と同様にしてシミュレーションを実施した。傾斜角度θ3およびθ4が0°の場合が比較例、傾斜角度θ3およびθ4が2°、6°、および、10°の場合が実施例である。
以上の結果より本発明の効果は明らかである。
12 管状部材
12a 接続孔
18 防音フード
20 風量調整部材
22、22b 消音構造体
23a、23b 部品
24 多孔質吸音材
25a、25b 切り欠き
26 開口
30 空洞部
31a~31d 面
32 開口部
36、36b~36g リブ構造
80、81 板
122 従来の消音器
Ix 管状部材の中心軸
W1 横断面における開口部側の空洞部の幅
W2 横断面における閉塞部側の空洞部の幅
W3 正面断面における開口部側の空洞部の幅
W4 正面断面における閉塞部側の空洞部の幅
θ1~θ4 面の傾斜角度
Da、Db 金型
D 汚れ
H リブ高さ
Claims (9)
- 管状部材に設置される消音構造体であって、
前記消音構造体は、空洞部、前記空洞部と前記管状部材とを連通する開口部、および、前記開口部と対面する位置で前記空洞部を閉塞する閉塞部を有し、
前記開口部側の前記空洞部の断面積が、前記閉塞部側の前記空洞部の断面積よりも大きい消音構造体。 - 前記空洞部の、前記開口部と接しない頂点に接する線分同士がなす角度の少なくとも1つが、π/2[rad]より大きい請求項1に記載の消音構造体。
- 前記管状部材の軸方向に垂直な断面において、前記空洞部の幅が、前記開口部から離間するにしたがって狭くなっている請求項1または2に記載の消音構造体。
- 前記消音構造体がリブ構造を有する請求項1~3のいずれか一項に記載の消音構造体。
- 前記消音構造体を構成する部材の密度が0.5g/cm3~2.5g/cm3である請求項1~4のいずれか一項に記載の消音構造体。
- 前記空洞部内に多孔質吸音材を有する請求項1~5のいずれか一項に記載の消音構造体。
- 請求項1~6のいずれか一項に記載の消音構造体を前記管状部材に設置した消音システムであって、
同じ形状の部品からなる2以上の消音構造体を有する消音システム。 - 請求項1~6のいずれか一項に記載の消音構造体を前記管状部材に設置した消音システムであって、
2以上の消音構造体を有し、
少なくとも2つの消音構造体が1つの金型で形成されたものである消音システム。 - 請求項1~6のいずれか一項に記載の消音構造体を前記管状部材に設置した消音システムであって、
前記消音構造体は、前記管状部材の軸方向に垂直な断面積のうち、50%以上塞がない消音システム。
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JP2001303926A (ja) * | 2000-04-28 | 2001-10-31 | Nippon Glass Fiber Kogyo Kk | 消音体、消音器及びその製造方法 |
JP2005030308A (ja) * | 2003-07-14 | 2005-02-03 | Toyota Boshoku Corp | 消音装置 |
JP2011058412A (ja) * | 2009-09-09 | 2011-03-24 | Toyota Motor Corp | 気流通路放射音低減構造 |
JP2016133226A (ja) * | 2015-01-15 | 2016-07-25 | 三菱電機株式会社 | 送風機の消音器 |
JP2017531143A (ja) * | 2014-08-06 | 2017-10-19 | エーエーエフ・リミテッド | 音抑制装置 |
JP2019133122A (ja) | 2017-07-05 | 2019-08-08 | 富士フイルム株式会社 | 消音システム |
JP2020024354A (ja) * | 2017-12-06 | 2020-02-13 | 富士フイルム株式会社 | 防音システム |
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JP2001303926A (ja) * | 2000-04-28 | 2001-10-31 | Nippon Glass Fiber Kogyo Kk | 消音体、消音器及びその製造方法 |
JP2005030308A (ja) * | 2003-07-14 | 2005-02-03 | Toyota Boshoku Corp | 消音装置 |
JP2011058412A (ja) * | 2009-09-09 | 2011-03-24 | Toyota Motor Corp | 気流通路放射音低減構造 |
JP2017531143A (ja) * | 2014-08-06 | 2017-10-19 | エーエーエフ・リミテッド | 音抑制装置 |
JP2016133226A (ja) * | 2015-01-15 | 2016-07-25 | 三菱電機株式会社 | 送風機の消音器 |
JP2019133122A (ja) | 2017-07-05 | 2019-08-08 | 富士フイルム株式会社 | 消音システム |
JP2020024354A (ja) * | 2017-12-06 | 2020-02-13 | 富士フイルム株式会社 | 防音システム |
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