JP2010110395A - Sound-deadening structure, vacuum cleaner, and air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound-deadening structure capable of effectively reducing the entire sound transmitted inside an air path, to further provide an apparatus with the sound-deadening structure, and also to provide a sound-deadening structure which has a long service life and can maintain a sound-deadening effect over a long period of time. <P>SOLUTION: The sound-deadening structure 50 is disposed inside the air path 10, disposed at a position corresponding to an "antinode" part of a sound pressure mode by air column resonance of at least the air path 10, and is constituted by cylindrically molding a resin material. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a silencing structure that effectively reduces sound propagating in an air passage, an electric vacuum cleaner including the silencing structure, and an air conditioner including the silencing structure.

  Conventionally, various countermeasures for noise generated from a vacuum cleaner have been studied. As one of them, a technique is disclosed in which noise generated from a suction port connected to a main body of a vacuum cleaner is silenced. As such, “in a main body having a suction port, a rotary pipe connected to an extension pipe is rotatably attached, and a silencer member is attached to the rotary pipe, the extension pipe and the rotary pipe There has been proposed a suction port for a vacuum cleaner in which a bent portion is formed in the connecting portion or the rotating tube itself so that the extension tube connecting portion faces upward (see, for example, Patent Document 1).

  In the vacuum cleaner described in Patent Document 1, a sound deadening portion is provided so as to be closest to the suction tool of the pipe portion in the suction path of the vacuum cleaner, and a sound absorbing material is installed on the inner wall of the sound deadening portion. The material was held with paper or a polyester film. When cleaning is started with an electric vacuum cleaner, airflow is first induced from the floor suction tool to the main body of the vacuum cleaner through the extension pipe and the bellows-like hose body due to the negative pressure generated by the electric blower. At that time, fluid noise is generated according to the turbulence of the air flow generated when the suction tool sucks, and unpleasant noise is radiated from the suction tool and the cleaner body. Therefore, in the vacuum cleaner described in Patent Document 1, an unpleasant noise is reduced by providing a silencer.

Japanese Patent Laid-Open No. 55-50329 (2nd page, FIG. 2)

  In the structure of the electric vacuum cleaner described in Patent Document 1, it is possible to reduce noise generated in the vicinity of the suction port due to turbulent flow. However, in such a structure, the noise generated inside the vacuum cleaner body that propagates in the direction of the suction port from the vacuum cleaner body, and the overall length of the vacuum cleaner body including the pipe part and the pipe part, contrary to the suction airflow sound The peak frequency noise component due to the air column resonance determined in step 1, vibration and friction noise generated by exciting the pipe itself when the airflow passes through the pipe, the sound radiation component transmitted from the pipe itself to the outside of the pipe, and the rotating brush There is a problem that it is difficult to attenuate the N component (for example, 1000 to 2000 Hz) of the rotary motor that rotates the rotary brush in the provided one.

  A paper or polyester film that holds the sound absorbing material due to dust or other protrusions sucked from the suction port, or dust caused by friction between the dust sucked from the suction port and the paper or polyester film. Damaged, the sound absorbing material protrudes into the pipe, causing a problem of scattering the sound absorbing material into the pipe. In addition, depending on the type of the sound absorbing material, there has been a problem that the sound absorbing characteristics cannot be obtained, and that the sound absorbing material itself cannot maintain the sound absorption rate due to deterioration over time. Furthermore, there is a problem that the membrane vibration cannot be obtained with the polyester film, and the sound absorbing material that is restrained by the film is reflected by the polyester film without incident sound emission of noise, and the expected sound absorbing effect cannot be obtained. there were.

  The present invention has been made to solve the above-described problems, and provides a muffler structure capable of effectively reducing all of the sound propagating in the air passage and a facility device including the same. The purpose is that. In addition, an object of the present invention is to provide a muffler structure, a vacuum cleaner, and an air conditioner that have a long life and can maintain a muffling effect over a long period of time.

  A silencing structure according to the present invention is a silencing structure disposed in an air passage, and is disposed at a position corresponding to at least a “belly” portion of a sound pressure mode by air column resonance of the air passage. It is characterized in that the material is molded into a cylindrical shape. The vacuum cleaner according to the present invention is a vacuum cleaner having a vacuum cleaner body, a suction tool, and a pipe connecting the vacuum cleaner body and the suction port. The pipe is provided. Furthermore, an air conditioner according to the present invention includes an indoor unit, a suction duct that conducts outside air supplied to the indoor unit, and a blowout duct that conducts air supplied from the indoor unit. The sound deadening structure is provided in at least one of the outlet duct and the suction duct.

  The silencing structure according to the present invention can be configured without a complicated structure, and is disposed at least at a position corresponding to the “antinode” portion of the sound pressure mode due to air column resonance of the air passage. Can be attenuated in a substantially entire frequency band of the sound propagating through. Moreover, according to the vacuum cleaner and the air conditioner according to the present invention, since the sound deadening structure is provided, the sound deadening structure can be easily incorporated, and the noise is stably reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a schematic view illustrating a configuration of a muffler structure 50 according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of the arrangement state of the sound deadening structure 50. Based on FIG.1 and FIG.2, the structure and effect | action of the silencing structure 50 are demonstrated. The silencing structure 50 is disposed in the air passage and reduces sound propagating in the air passage. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one. In FIG. 2, the flow of sound propagating in the air passage 10 is indicated by broken line arrows, and the airflow flowing in the air passage 10 is indicated by solid line arrows.

  As shown in FIG. 1, the sound deadening structure 50 includes a sound absorbing material 72 and a hollow portion 76. That is, the sound deadening structure 50 is configured by molding the sound absorbing material 72 into a cylindrical shape so as to form the hollow portion 76. This sound absorbing material 72 contains a resin material such as PET (including polyethylene terephthalate and recycled PET), urethane foam material, or felt-like fiber material (nonwoven fabric). The sound absorbing material 72 has a length of 10 mm or more and a thickness of 5 μm or less. The thickness of the molded sound absorbing material 72 is 5 mm or more. In addition, in FIG. 1, although the case where the sound-absorbing material 72 is shape | molded by the cylinder shape is shown as an example, it is not limited to this, You may shape | mold in the shape of a square tube.

  The sound absorbing material 72 is obtained by crushing a resin material having a thickness of 5 μm or less and molding the resin material to an arbitrary length of 10 mm or more, and then adding a binder material having a thickness of 5 μm or less and an arbitrary length of 10 mm or more. % To 35%, and the resin fiber material is refined, heated and compressed, and molded so as to obtain a required basis weight (g / m 2). Due to the effect of the kneaded binder material, it becomes possible to maintain / manage the thickness of the sound absorbing material 72, for example, 5 mm or more. The binder material is made of a resin material different from PET, a urethane foam material, or a felt-like fiber material, which is the main material of the sound absorbing material 72.

  The thickness and length of the resin material and the binder material constituting the sound absorbing material 72 are set in the above ranges in consideration of the influence on the human body. Since the sound deadening structure 50 is disposed in the air passage, a part of the resin material and the binder material constituting the sound absorbing material 72 may be discharged outside the air passage along the air flow. In this case, if the thickness and length of the resin material and the binder material are set to the above range or less, the resin material or the binder material sucked into the human body reaches the lungs and accumulates. become. Therefore, in the sound deadening structure 50, by setting the thickness and length of the resin material and the binder material constituting the sound absorbing material 72 within the above ranges, even if the human body is inhaled, it does not reach the lungs. I have to.

  The binder material may be a polymer resin, and for example, a polymer resin such as polyethylene (PE) or polypropylene (PP) can be used. Further, the thickness of the sound absorbing material 72 composed of the resin material and the binder material may be 5 mm or more, but is preferably about 10 mm in consideration of the inner diameter of the air passage in which the sound deadening structure 50 is disposed. That is, the thickness of the sound absorbing material 72 may be 5 mm or more, and may be a thickness such that the hollow portion 76 is formed when molded into a cylindrical shape.

  The muffler structure 50 configured as described above is disposed in the air passage 10 as shown in FIG. This air passage 10 is assumed to be a pipe of a vacuum cleaner according to the second embodiment or a duct of an air conditioner according to the third embodiment. As shown in FIG. 2, in the air passage 10, there is a sound flow (broken arrow) along with an air flow (solid arrow). The sound existing in the air path 10 propagates in the air path 10 in both directions. When this sound leaks to the outside of the air passage 10, it is radiated as unpleasant noise.

As will be described in detail in the second embodiment, in the air passage 10, a dense wave due to the “antinode” and “node” of the sound pressure mode is formed in the length of the air passage 10, and this becomes air column resonance. A peak frequency component peculiar to the frequency characteristic of noise is generated. Although this peak frequency component varies depending on the total length of the air passage 10, it can be determined by the following calculation formula.
Formula f = C (n) / 2L
Here, C represents the speed of sound, n represents the order, and L represents the total length of the air passage 10.

  Therefore, the silencing structure 50 is arranged at a position corresponding to at least a “belly” portion of the sound pressure mode by air column resonance of the air passage 10. By disposing the muffler structure 50 at such a position, not only the sound propagating in the air passage 10 but also the sound pressure of the peak frequency component peculiar to the frequency characteristic of the noise generated by the air column resonance of the air passage 10 is obtained. The level can be reduced. Therefore, it is possible to confirm the sound attenuation effect in substantially the entire frequency band of the noise propagating in the air passage 10. The silencing structure 50 is not particularly limited as long as it is disposed at least at a position corresponding to the “belly” portion of the sound pressure mode by the air column resonance of the disposed air passage 10.

  FIG. 3 is a schematic cross-sectional view showing a state in which the film portion 73 is formed on the inner peripheral surface side of the sound absorbing material 72. FIG. 4 is an enlarged cross-sectional view showing a part of the muffler structure 50 in an enlarged manner. Based on FIG.3 and FIG.4, the effect | action of the sound deadening structure 50 of the state which formed the film part 73 in the inner peripheral surface side of the sound-absorbing material 72 is demonstrated. In the silencing structure 50, air is conducted through the hollow portion 76. Therefore, when dust such as dust or dust is sucked together with the air, the dust is accumulated between the fibers of the resin material and the binder material constituting the sound absorbing material 72. It will be. Further, the sound absorbing material 72 may be damaged by the sucked dust. If the air passage 10 is a duct of an air conditioner, there is no particular problem, but if the air passage 10 is a pipe of a vacuum cleaner, it is required to take measures against dust that is sucked together with air.

  Therefore, as shown in FIG. 3, a film portion 73 is formed on the inner peripheral surface side of the sound absorbing material 72 so as not to be affected by dust sucked together with air. The thickness of the coating 73 is 35 μm or more and 100 μm or less (details will be described in the second embodiment). In the case where PET is used as the resin material constituting the sound absorbing material 72, the coating 73 can be produced by molding PET into a film. In this case, the sound absorbing material 72 and the coating portion 73 can be brought into close contact with an adhesive (adhesive layer 75 shown in FIG. 4) containing a PET powder material that is the same material. Moreover, durability and intensity | strength can be ensured, obtaining the adhesiveness with the sound-absorbing material 72 by comprising the film part 73 with PET.

  As shown in FIG. 4, when the coating 73 is made of PET, an adhesive containing PET powder or the like pulverized into a powder is applied to the surface in contact with the sound absorbing material 72 and applied as the adhesive layer 75. be able to. By using the mold, the film portion 73 can be fixed to the inner peripheral surface side of the sound absorbing material 72 through the adhesive layer 75 in an accurate state according to the shape of the sound absorbing material 72 (here, circular). And the sound-absorbing material 72 to which the coating 73 is adhered is fixed to the inside of the air passage 10 with an adhesive layer 78 made of an arbitrary adhesive material.

  Furthermore, the film part 73 can also be formed by dissolving the inner peripheral surface side of the sound absorbing material 72 and then solidifying it. That is, the film part 73 may be produced separately from the sound absorbing material 72, or the film part 73 may be produced by deforming the inner peripheral surface side of the sound absorbing material 72. Moreover, although the case where both the resin material which comprises the sound-absorbing material 72, and the film part 73 are PET was demonstrated to the example, the combination with another resin material may be sufficient. For example, the resin material constituting the sound absorbing material 72 may be a urethane foam material and the coating portion 73 may be PET. By providing such a coating portion 73 on the inner peripheral surface side of the sound absorbing material 72, it is possible to achieve a noise reduction effect even if it is disposed in the air passage 10 where dust is sucked.

  FIG. 5 is a schematic cross-sectional view showing a state in which the resin net 80 is provided on the inner peripheral surface side of the sound absorbing material 72. Based on FIG. 5, the operation of the sound deadening structure 50 in a state where a resin net (hereinafter referred to as a resin net 80) is provided on the inner peripheral surface side of the sound absorbing material 72 will be described. FIG. 5 shows a state in which the resin net 80 is provided on the surface of the film part 73. When the strong air current is conducted through the hollow portion 76, the coating portion 73 may be peeled off. In order to prevent this, in the sound deadening structure 50, the resin net 80 is provided on the surface of the coating portion 73.

  The resin net 80 is configured by molding a resin material (for example, PET, PP, PE, etc.) having a thickness of about 50 μm in a lattice shape. By providing the resin net 80 on the surface of the coating portion 73, the coating portion 73 is prevented from being peeled off. In the case where the coating portion 73 is made of PET, if the resin net 80 is made of PET, the coating portion 73 and the resin net 80 can be brought into close contact with an adhesive containing a PET powder material which is the same material. . Moreover, although the case where the thickness of the resin net 80 was about 50 micrometers was demonstrated to the example, it is not limited to this.

  FIG. 6 is a schematic cross-sectional view showing a state in which the peeling preventing jig 90 is provided on both end faces of the sound absorbing material 72. Based on FIG. 6, the operation of the sound deadening structure 50 in a state in which the peeling prevention jig 90 is provided on both end faces of the sound absorbing material 72 will be described. Although FIG. 6 shows a state in which the peeling prevention jig 90 is provided on both end faces of the sound absorbing material 72, it is sufficient that the peeling prevention jig 90 is provided on at least one end face. Moreover, although the case where the film part 73 is provided is shown, the film part 73 may not be provided. When the air current is conducted through the hollow portion 76, the sound absorbing material 72 may be peeled off. In order to prevent this, the sound deadening structure 50 is provided with a peeling prevention jig 90 on both end faces of the sound absorbing material 72.

  The peeling prevention jig 90 is fixed inside the air passage 10 and is configured to restrict the movement of the silencing structure 50 by covering both end faces of the silencing structure 50. By providing the peeling preventing jig 90 on both end faces of the sound absorbing material 72, the sound absorbing material 72 is prevented from peeling. In addition, the peeling prevention jig | tool 90 should just be a thing which can control the motion of the sound deadening structure 50, and does not specifically limit a constituent material, a magnitude | size, and a shape. Moreover, you may make it use together with the resin net 80 demonstrated in FIG.

  As described above, the silencing structure 50 can be configured without a complicated structure, and the silencing structure 50 is disposed at least at a position corresponding to the “antinode” portion of the sound pressure mode by the air column resonance of the air passage 10. Not only the sound propagating in the air passage 10 but also the sound pressure level of the peak frequency component peculiar to the frequency characteristic of the noise generated by the air column resonance of the air passage 10 can be reduced. Further, the coating 73, the resin net 80, or the peeling prevention jig 90 can be provided in accordance with the air passage 10 in which the sound deadening structure 50 is disposed, and safety and durability can be improved.

  FIG. 12 is a cross-sectional view showing an air path cross-sectional configuration of a muffler structure 50 in which a slit part 200 which is an example of an opening is provided in a part of the film part 73. FIG. 13 is a cross-sectional view showing the AA cross section of FIG. FIG. 14 is a cross-sectional view showing a modification of the slit portion 200 and showing the AA cross section of FIG. Based on FIGS. 12-14, the effect | action of the muffling structure 50 of the state which provided the slit part 200 in a part of film part 73 is demonstrated. 12A is a sectional view showing the basic structure of the silencing structure 50, and FIG. 12B is a sectional view showing a state in which the silencing structure 50 is arranged in the air passage 10.

  As shown in FIG. 12 (b), the silencing structure 50 is arranged in the air passage 10 such as a pipe of an electric vacuum cleaner or a duct of an air conditioner described in the second or third embodiment. It has become. The slit portion 200 is formed to have a width W of 1 mm or more. By providing such a slit portion 200 in the coating portion 73, sound waves flowing in the coating portion 73 are also incident on the sound absorbing material 72. Therefore, sound absorption processing corresponding to the area of the sound absorbing material 72 is performed, and sound absorption characteristics in a low frequency band of 500 Hz or less can be improved. Moreover, the slit part 200 exhibits the same effect also in the partial slit type comprised by the slit which has several opening area. For example, as shown in FIG. 14, the slits having a plurality of opening areas may be arranged in a staggered manner.

  FIG. 15 is a schematic view illustrating a state in which a decoating portion 220, which is an example of an opening, is formed in a part of the coating portion 73. Based on FIG. 15, the operation of the sound deadening structure 50 in a state in which the film removal portion 220 is formed on a part of the film portion 73 will be described. As shown in FIG. 15, with respect to the coating part 73, a part (decoated part 220) that does not adhere to the coating part 73 having an arbitrary area is formed on a part of the coating part 73 at both ends of the sound deadening structure 50 or around. Make sure you do. By forming such a decoating portion 220, sound waves are incident on a portion without the coating (decoating portion 220), and the sound absorbing effect of the sound absorbing material 72 can be exhibited. Therefore, also in this case, the sound absorption characteristics in a low frequency band of 500 Hz or less can be improved.

  FIG. 16 is a graph showing the frequency characteristics of noise when the slit portion 300 or the decoating portion 220 is provided in the coating portion 73. Based on FIG. 16, the frequency characteristic of the noise when the slit part 300 or the film removal part 220 is provided in the film part 73 will be described. Although the frequency characteristics described here will be described in detail in the second embodiment, the noise reduction structure 50 is arranged in the pipe of the vacuum cleaner described in the second embodiment, and the frequency of noise generated from the vacuum cleaner. It represents a characteristic. In FIG. 16, the vertical axis represents the sound pressure level (dB) and the horizontal axis represents the frequency (Hz).

  In FIG. 16, the frequency characteristic in a state where the line (A) does not apply the silencing structure 50 (before the countermeasure member (the silencing structure 50) is mounted), and the state where the line (Q) applies the silencing structure 50 ( The frequency characteristics of the countermeasure member are shown). That is, the specific peak frequency component is generated in the frequency characteristic in a state where the silencing structure 50 is not applied, but the specific peak frequency is generated in the frequency characteristic in which the silencing structure 50 is applied to the frequency characteristic. The sound attenuation effect in almost the entire frequency band including the components can be confirmed. Moreover, since the film part 73 of the sound deadening structure 50 is provided with the slit part 200 or the film removal part 220, it can be confirmed that the sound absorption characteristics in the low frequency band of 500 Hz or less can be improved.

Embodiment 2. FIG.
FIG. 7 is a perspective view showing an external configuration of a vacuum cleaner 20 that is an example of equipment according to Embodiment 2 of the present invention. Based on FIG. 7, the structure and operation | movement of the vacuum cleaner 20 as an example of an installation apparatus are demonstrated. The vacuum cleaner 20 is located in the pipe 55 that is the air path of the muffler structure 50 according to the first embodiment, and at least a position corresponding to the “belly” portion of the sound pressure mode by air column resonance that the pipe 55 has Therefore, the sound propagating through the pipe 55 is reduced.

  This electric vacuum cleaner 20 is provided with a dust collection chamber for storing a dust collection bag for collecting dust, an electric blower 2 (hereinafter simply referred to as a motor 2) for generating an air flow, and the like. A vacuum cleaner main body 1 provided with a main body suction port 3 to be sucked, a suction tool 60 having a suction port for sucking dust on the surface to be cleaned together with air to the vacuum cleaner main body 1, and a removable suction tool 60. A pipe 55 that is connected to send dust and air sucked from the intake port to the cleaner body 1 and a bendable bellows-like hose 4 that detachably connects the pipe 55 and the body suction port 3 of the cleaner body 1. And a hand handle 7 provided at one end of the hose 4 (an end connected to the pipe 55) and provided with an operation portion 7a that allows a user to select an operation mode of the electric blower 2 and the like. .

  An operation mode of the motor 2 is determined by operating a start switch provided in the operation unit 7a, and the motor 2 rotates at high speed according to the operation mode. A pipe 55 is connected to one end of the hand handle 7 (the end that is not the end connected to the hose 4). The pipe 55 is configured to be extendable, variable in overall length by connection, or seamlessly, and is provided with the sound deadening structure 50 according to the first embodiment. That is, the pipe 55 is the air passage 10 described in the first embodiment. Further, it is assumed that the sound deadening structure 50 is provided with a film portion 73.

  In the length from the suction port formed in the suction tool 60 of the electric vacuum cleaner 20 to the vacuum cleaner body 1, a dense wave due to the “belly” and “node” in the sound pressure mode is formed inside the pipe 55, which is It becomes air column resonance and generates a peak frequency component peculiar to the frequency characteristic of noise. This frequency varies depending on the total length of the pipe 55 or the vacuum cleaner 20 including the pipe 55, but a frequency determined by the calculation formula shown in the first embodiment is generated.

  Further, the rotation sound of the motor generated in the cleaner body 1 propagating from the cleaner body 1 to the suction tool 60 and the sound accompanying the flow of fluid (air) are radiated from the suction tool 60 and the pipe 55 through the pipe 55. (Including transmitted sound). Furthermore, the fluid sound in the pipe 55 and the vibration sound accompanying the fluid flow are also radiated from the pipe 55. Therefore, in the electric vacuum cleaner 20 according to the second embodiment as a countermeasure against these noises, the muffler structure 50 is arranged in the pipe 55 in accordance with the connection state of the pipe 55. The length of the sound deadening structure 50 is molded in accordance with the length of the pipe 55 that performs the sound absorption process. However, by arranging the sound deadening structure 50 at the “belly” portion of the sound pressure mode where the air column resonance occurs, The sound pressure level of the peak frequency component can be effectively reduced.

The operation of the sound deadening structure 50 arranged in the pipe 55 will be described.
When the motor 2 is driven, airflow and sound (noise) flow inside the pipe 55 (see FIG. 2). The noise radiated from the pipe 55 includes sound generated when air is sucked by the suction tool 60, sound generated by air column resonance in the pipe 55, and pipe 55 itself when the air passes through the pipe 55. Vibration sound and friction sound generated by vibration, sound transmitted from the pipe 55 itself to the outside of the pipe 55, sound generated in the cleaner body 1 flowing backward from the cleaner body 1, and a rotating brush in a thing equipped with a rotating brush It consists of the sound of a rotating motor that rotates.

  The sound-absorbing structure 50 that constitutes the sound-absorbing material 72 and the coating portion 73 with PET will be described as an example. The acoustic signal accompanying the noise described above first enters the coating portion 73. PET originally has oxygen permeability, and this action causes an acoustic signal that has passed through the coating 73 to enter the sound absorbing material 72 at the next stage. The coating part 73 made of PET has a characteristic tendency that the coating part 73 is vibrated by an acoustic wave with a viscosity (flexibility) unique to the film according to the thickness of the coating part 73, and only an arbitrary frequency band is greatly attenuated. Have. Regarding other frequency bands, sound attenuation is performed in accordance with the sound absorption coefficient corresponding to the thickness and the basis weight of the sound absorbing material 72 after passing through the coating 73.

  By these actions, the frequency component of the air column resonance determined by the pipe 55 and the entire length of the vacuum cleaner 20 including the pipe 55 and the sound signal component contributing to the frequency characteristics of the noise propagating through the pipe 55 are effectively attenuated. Will be able to. The sound absorbing material 72 has a constant thickness in the pipe 55 due to the effect of maintaining the thickness with the binder material kneaded at the time of molding, and affects the air and dust passing through the pipe 55. The shape change such as dents is not generated. Further, by forming the coating portion 73 to be in close contact with the surface of the sound absorbing material 72 into a cylindrical shape, the strength of the sound absorbing material 72 is maintained, and the shape change in the pipe 55 does not occur. Furthermore, by providing the resin net 80 and the peeling prevention jig 90, peeling of the sound absorbing material 72 and the film part 73 can be prevented.

  FIG. 8 is a graph showing the frequency characteristics of noise generated from the vacuum cleaner 20 when the silencing structure 50 is applied to the pipe 55. FIG. 9 is a graph showing the frequency characteristics of noise generated from the vacuum cleaner 20 when the thickness of the coating 73 is changed. FIG. 10 is a graph showing frequency characteristics of noise generated from the electric vacuum cleaner 20 when the thickness of the sound absorbing material 72 is changed. Based on FIGS. 8-10, the frequency characteristic of the noise which generate | occur | produces from the vacuum cleaner 20 to which the silencing structure 50 is applied is demonstrated. 8 to 10, the vertical axis represents the sound pressure level (dB) and the horizontal axis represents the frequency (Hz).

  In FIG. 8, the line (A) shows the frequency characteristics in a state where the silencing structure 50 is not applied (before the countermeasure member (silencing structure 50) is mounted), and the line (A) shows the state where the silencing structure 50 is applied ( The frequency characteristics of the countermeasure member are shown). That is, the specific peak frequency component is generated in the frequency characteristic in a state where the silencing structure 50 is not applied, but the specific peak frequency is generated in the frequency characteristic in which the silencing structure 50 is applied to the frequency characteristic. The sound attenuation effect in almost the entire frequency band including the components can be confirmed.

  Therefore, when cleaning is performed using the electric vacuum cleaner 20 to which the sound deadening structure 50 is applied, noise radiated from the suction tool 60 through the pipe 55 from the vacuum cleaner body 1, fluid sound generated by the suction tool 60, generated in the pipe 55. The sound emission of the fluid noise component is effectively attenuated, and the component of the transmitted sound that is transmitted through the surface of the pipe 55 and radiates to the outside of the pipe 55 can also be reduced. Will be reduced. In addition, in the thing provided with a rotary brush in a suction tool, the noise which generate | occur | produces from the rotary motor which rotates a rotary brush can also be reduced.

  In FIG. 9, the frequency characteristic in a state where the line (A) does not apply the silencing structure 50, and the state in which the silencing structure 50 provided with the coating 73 having a thickness of 100 μm or more in the line (C) is applied. The frequency characteristics are respectively shown in the state in which the sound deadening structure 50 provided with the coating 73 having a thickness of 100 μm or less in the line (d) is applied. Here, frequency characteristics in the case where the coating 73 is made of PET are shown. As described with reference to FIG. 8, when compared with the frequency characteristics in a state where the silencing structure 50 is not applied, the frequency characteristics in a state where the silencing structure 50 is applied confirms the sound attenuation effect in the entire frequency band. it can.

  In addition, in the case where the film portion 73 having a thickness of 100 μm or less is provided, the case where the film portion 73 having a thickness of 100 μm or less is provided, the sound in a substantially entire frequency band including a specific peak frequency component. The attenuation effect can be confirmed. Therefore, it can be seen that in order to reduce noise more effectively, it is desirable that the thickness of the coating 73 is 100 μm or less. In addition, since durability and intensity | strength will reduce if the thickness of the film part 73 is too thin, the thickness of the film part 73 is 35 micrometers or more.

  In FIG. 10, the frequency characteristic in a state where the sound absorbing structure 50 is not applied to the line (A), and the sound absorbing structure 50 provided with the sound absorbing material 72 having a thickness of 5 mm or less in the line (A) is applied. The frequency characteristics are respectively shown in the state where the sound deadening structure 50 provided with the sound absorbing material 72 having a line (f) of 10 mm or more is applied. As described with reference to FIG. 8, when compared with the frequency characteristics in a state where the silencing structure 50 is not applied, the frequency characteristics in a state where the silencing structure 50 is applied confirms the sound attenuation effect in the entire frequency band. it can.

  In addition, in the case where the sound absorbing material 72 having a thickness of 5 mm or less is provided, the sound absorption material 72 having a thickness of 10 mm or more includes sound in a substantially entire frequency band including a specific peak frequency component. The attenuation effect can be confirmed. Therefore, it can be seen that in order to reduce noise more effectively, it is desirable that the thickness of the sound absorbing material 72 is 5 mm or more, preferably about 10 mm. However, the thickness of the sound absorbing material 72 may be determined in consideration of the inner diameter of the pipe 55 in which the sound deadening structure 50 is disposed.

  As described with reference to FIGS. 8 to 10, when the muffling structure 50 is applied, the sound attenuation effect in substantially the entire frequency band of the vacuum cleaner 20 as compared to a vacuum cleaner not using the muffling structure 50. Will be obtained. Further, by setting the thickness of the sound absorbing material 72 of the sound deadening structure 50 to be applied and the thickness of the coating portion 73 within the ranges shown in FIGS. 9 and 10, it is possible to further reduce noise more effectively. it can.

  By the way, a film containing an antistatic agent is formed on the film part 73 facing the hollow part 76 of the sound deadening structure 50, or a film part 73 is formed by mixing antistatic agent additives. Thus, it is possible to prevent the dust from adhering to the surface of the coating 73 due to the friction generated when the dust passes through the hollow portion 76. In this way, even if the vacuum cleaner 20 is used for a long period of time, the sound absorbing material 72 is less contaminated with dust, and the sound absorbing surface is not covered by dust accumulation, so that the sound absorbing effect is prolonged. The period can be kept constant. Therefore, the noise performance of the vacuum cleaner 20 can be kept constant for a long period. In addition, although the kind of antistatic agent is not specifically limited, For example, magnesium chloride, sodium chloride, sodium sulfate, calcium chloride, potassium chloride, an anionic polymer, a cationic polymer, etc. are applicable.

  As described above in detail, by providing the sound deadening structure 50 provided with the coating portion 73 on a part and the entire length of the inside of the pipe 55, adhesion of dust to the sound absorbing material 72 is suppressed, and air column resonance is achieved. It is possible to reduce the peak frequency component due to the noise and to have sound absorption performance for all the bands that affect the frequency band of noise. In addition, the silencer structure 50 with a simple configuration can be easily incorporated into a home appliance such as the vacuum cleaner 20, and a home appliance with less noise can be provided stably.

Embodiment 3.
FIG. 11 is a schematic diagram illustrating an example of an installation state of the air-conditioning apparatus 30 that is an example of the equipment according to Embodiment 3 of the present invention. Based on FIG. 11, the structure and operation | movement of the air conditioning apparatus 30 as an example of an installation apparatus are demonstrated. The air conditioner 30 is located in the duct 35 that is the air path of the muffler structure 50 according to the first embodiment, and corresponds to at least a “belly” portion of the sound pressure mode by air column resonance that the duct 35 has. Therefore, the sound propagating through the duct 35 is reduced. The air conditioner 30 performs a cooling operation or a heating operation using a refrigeration cycle (not shown) for circulating a refrigerant.

  The air conditioner 30 includes an outdoor unit 31 provided with a compressor, a heat exchanger, and the like, and an indoor unit 32 provided with a heat exchanger, a blower, an expansion valve, and the like. The outdoor unit 31 and the indoor unit 32 are connected by a refrigerant pipe 33 that conducts the refrigerant, and the cold or warm heat generated by the outdoor unit 31 is delivered to the indoor unit 32. The number of connected outdoor units 31 and indoor units 32 is not particularly limited. The outdoor unit 31 is disposed in an outdoor space 44 that is a space outside a building 41 such as a building, and supplies cold or warm heat to the indoor unit 32. The indoor unit 32 is disposed at a position (hereinafter referred to as a non-residential space 42) different from the living space 43 such as a living room inside the building 41 that can carry cooling air or heating air, and serves as an air conditioning target area. Cooling air or heating air is supplied to the living space 43.

  The outdoor space 44 imagines a place existing outside the building 41, for example, a rooftop as shown in FIG. The non-residential space 42 is an image of a place where people are not always present, such as a corridor, such as a common area with a ceiling of a common zone, an elevator, etc., a machine room, a computer room (server room), or a warehouse. Yes. The living space 43 is an image of a place where people always exist or a place where a large number or a small number of people exist temporarily, such as offices, classrooms, conference rooms, restaurants, and the like. In addition, the arrangement | positioning place of the outdoor unit 31 and the indoor unit 32 is not limited to the position shown in figure.

  The outdoor unit 31 and the indoor unit 32 are connected using two refrigerant pipes 33. The indoor unit 32 is connected to a duct 35 (a blowout duct 35a and a suction duct 35b). The blowout duct 35 a is connected to a blowout port 38 provided in a part of the living space 43 (here, the ceiling surface), and conducts cooling air or heating air supplied from the indoor unit 32 to the living space 43. To do. The suction duct 35b is connected to an outside air suction port 39 provided in a part of the building 41 (here, a wall surface), and conducts the outside air from the outdoor space 44 to the indoor unit 32.

  Both the blow-out duct 35a and the suction duct 35b serve as an air passage through which air is conducted, and noise is generated with the flow of air. Therefore, the noise reduction structure 50 according to the first embodiment is arranged in the blowout duct 35a and the suction duct 35b to reduce noise. However, when the muffler structure 50 is disposed in the blowout duct 35a and the suction duct 35b, the coating 73 is not required because less dust is sucked.

  In the lengths of the blowout duct 35a and the suction duct 35b, a dense wave due to the “antinode” and “node” of the sound pressure mode is formed inside the blowout duct 35a and the suction duct 35b, which becomes air column resonance, and the frequency characteristics of noise. A peculiar peak frequency component is generated. This frequency varies depending on the total length of the blowout duct 35a and the suction duct 35b, but a frequency determined by the calculation formula shown in the first embodiment is generated. In addition, sound generated from a blower, an expansion valve (not shown) provided in the indoor unit 32, and sound accompanying the flow of fluid (air) are radiated from the blowout duct 35a and the suction duct 35b (including transmitted sound). Is done. Furthermore, the fluid sound in the blowing duct 35a and the suction duct 35b and the vibration sound accompanying the flow of the fluid are also radiated from the blowing duct 35a and the suction duct 35b.

  Therefore, in the air conditioner 30 according to Embodiment 3 as a countermeasure against these noises, the sound deadening structure 50 is arranged in the blowout duct 35a and the suction duct 35b in accordance with the connection state of the blowout duct 35a and the suction duct 35b. I have to. The length of the sound deadening structure 50 is formed in accordance with the length of the blowout duct 35a and the suction duct 35b for performing the sound absorption process. However, the sound absorption mode “anti-node” in which the air column resonance of the blowout duct 35a and the suction duct 35b occurs. The sound pressure level of the peculiar peak frequency component can be effectively reduced. Other actions and effects are as described in the second embodiment. In addition, although the case where the silencing structure 50 was arrange | positioned in both the blowing duct 35a and the suction duct 35b was demonstrated to the example, you may arrange the silencing structure 50 only in any one.

  As described above in detail, the provision of the silencing structure 50 in part and the entire length of the blowout duct 35a and the suction duct 35b reduces the peak frequency component due to air column resonance and affects the frequency band of noise. It is possible to have sound absorption performance for all the bands to be performed. In addition, the silencer structure 50 having a simple configuration can be easily incorporated into equipment such as the air conditioner 30, and equipment with stable and low noise can be provided.

It is the schematic which shows through the structure of the sound deadening structure which concerns on Embodiment 1. FIG. It is a schematic sectional drawing which shows an example of the arrangement | positioning state of a silencing structure. It is a schematic sectional drawing which shows the state in which the film part was formed in the inner peripheral surface side of a sound-absorbing material. It is an expanded sectional view which expands and shows a part of silencing structure. It is a schematic sectional drawing which shows the state which provided the resin net in the inner peripheral surface side of the sound-absorbing material. It is a schematic sectional drawing which shows the state provided with the peeling prevention jig | tool at the both end surfaces of the sound-absorbing material. It is a perspective view which shows the external appearance structure of the vacuum cleaner which is an example of the equipment based on Embodiment 2. FIG. It is a graph which shows the frequency characteristic of the noise which generate | occur | produces from a vacuum cleaner at the time of applying a silencing structure to a pipe. It is a graph which shows the frequency characteristic of the noise which generate | occur | produces from a vacuum cleaner at the time of changing the thickness of a film part. It is a graph which shows the frequency characteristic of the noise which generate | occur | produces from a vacuum cleaner at the time of changing the thickness of a sound-absorbing material. FIG. 10 is a schematic diagram illustrating an example of an installation state of an air conditioner that is an example of facility equipment according to Embodiment 3. It is sectional drawing which shows the wind-path cross-section structure of the silencing structure which provided the slit part which is an example of an opening part in a part of film part. It is sectional drawing which shows the AA cross section of FIG.12 (b). It is sectional drawing which shows the modification of a slit part and shows the AA cross section of FIG.12 (b). It is the schematic which shows through the state which formed the film removal part which is an example of an opening part in a part of film part. It is a graph which shows the frequency characteristic of the noise at the time of providing a slit part or a film removal part in a film part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Vacuum cleaner main body, 2 Electric blower, 3 Main body inlet, 4 Hose, 7 Hand handle, 7a Operation part, 10 Air path, 20 Vacuum cleaner, 30 Air conditioning apparatus, 31 Outdoor unit, 32 Indoor unit, 33 Refrigerant piping , 35 duct, 35a outlet duct, 35b suction duct, 38 outlet, 39 outside air inlet, 41 building, 42 non-residential space, 43 living space, 44 outdoor space, 50 silencer structure, 55 pipe, 60 suction tool, 72 Sound absorbing material, 73 coating part, 75 adhesive layer, 76 hollow part, 78 adhesive layer, 80 resin net, 90 peeling prevention jig, 200 slit part, 220 decoating part.

Claims (23)

A muffler structure disposed in an air passage,
A muffler structure, which is disposed at least at a position corresponding to a “belly” portion of a sound pressure mode by air column resonance of the air path and is formed by molding a resin material into a cylindrical shape. The silencing structure according to claim 1, wherein the length of the resin material is 10 mm or more, the thickness is 5 µm or less, and the thickness of the molded resin material is 5 mm or more. As the resin material,
The muffler structure according to claim 1 or 2, wherein polyethylene terephthalate, urethane foam material, or felt-like fiber material is contained. The muffler structure according to any one of claims 1 to 3, wherein a binder material made of a resin material different from the resin material is mixed with the resin material by 30% to 35%. The silencer structure according to claim 4, wherein the binder material has a length of 10 mm or more and a thickness of 5 µm or more. The muffler structure according to any one of claims 1 to 5, wherein an inner peripheral surface side of the resin material is coated. The silencing structure according to claim 6, wherein an opening having a predetermined area is provided at a predetermined position of the coating. The opening is
The silencer structure according to claim 7, wherein a slit is formed in a part of the film. A plurality of the slits are provided,
The silencer structure according to claim 8, wherein the plurality of slits are arranged in a staggered manner. The opening is
The silencer structure according to claim 7, wherein the sound deadening structure is configured by partially or circularly forming a surface to which the coating film is not fixed at an end portion of the air passage. The silencer structure according to any one of claims 6 to 10, wherein the thickness of the coating is 35 µm or more and 100 µm or less. The silencer structure according to any one of claims 6 to 11, wherein a film is formed by dissolving and solidifying an inner peripheral surface side of the resin material. In what constitutes the resin material with polyethylene terephthalate,
The resin film is molded with polyethylene terephthalate of the same material as the resin material, and the resin film is adhered to the inner peripheral surface side of the resin material to coat the resin material. The muffler structure described. The silencing structure according to claim 13, wherein the resin film and the resin material are adhered to each other with an adhesive containing a polyethylene terephthalate powder material. The silencer structure according to any one of claims 6 to 14, wherein a resin net molded in a lattice shape is provided on a surface of the coating. The silencing structure according to any one of claims 1 to 15, further comprising a peeling prevention jig that prevents peeling of the resin material on at least one end surface of the resin material. A film containing an antistatic material is formed on the surface of the coating film, or an antistatic material is kneaded with a resin material constituting the coating film. The silencing structure described in 1. A muffler structure disposed in an air passage,
Disposed at least at a position corresponding to the “antinode” portion of the sound pressure mode by air column resonance of the air passage,
On the surface of the sound-absorbing material molded from a resin material into a cylindrical shape,
In a sound absorbing structure provided with a film made of a resin material of 100 μm or less,
An opening having a predetermined area is provided at a predetermined position of the coating film. The opening is
The silencer structure according to claim 18, wherein a slit is formed in a part of the film. A plurality of the slits are provided,
The silencing structure according to claim 19, wherein the plurality of slits are arranged in a staggered manner. The opening is
The silencer structure according to claim 18, wherein the sound deadening structure is configured by partially or circularly forming a surface to which the coating film is not fixed at an end portion of the air path. A vacuum cleaner having a vacuum cleaner body, a suction tool, and a pipe connecting the vacuum cleaner body and the suction port,
An electric vacuum cleaner comprising the muffler structure according to any one of claims 1 to 21 in the pipe. An air conditioner having an indoor unit, a suction duct that conducts outside air supplied to the indoor unit, and a blowout duct that conducts air supplied from the indoor unit,
An air conditioner comprising the muffler structure according to any one of claims 1 to 21 in at least one of the blowout duct and the suction duct.

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