CN211288264U - Impedance combined type fan silencing box - Google Patents

Impedance combined type fan silencing box Download PDF

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Publication number
CN211288264U
CN211288264U CN201922191858.1U CN201922191858U CN211288264U CN 211288264 U CN211288264 U CN 211288264U CN 201922191858 U CN201922191858 U CN 201922191858U CN 211288264 U CN211288264 U CN 211288264U
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shell
case
cavity
box shell
box
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CN201922191858.1U
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Chinese (zh)
Inventor
张玉敏
张玉麟
李双成
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Beijing Wanxunda Acoustics Equipment Co ltd
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Beijing Wanxunda Acoustics Equipment Co ltd
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Abstract

The utility model relates to an impedance combined type fan noise reduction case, including cavity both ends open-ended case shell, well kenozooecium length direction's wherein one end is the air inlet in the case shell, the other end is the gas outlet, the case shell includes outside outer shell and is located the inside inner box shell that matches with outer shell shape of outer shell, leave space vacuole formation between inner box shell and the outer shell, inner box shell and outer shell length direction's both ends utilize the fixed plate to connect respectively, be provided with a plurality of through-holes that run through the inner box shell on the inner box shell, length direction along the case shell is provided with a plurality of baffles of cutting apart the cavity in the cavity, a plurality of resistance chambeies and a plurality of hindering nature chamber are cut apart into with the cavity to the baffle, resistance chamber and hindering nature chamber are asymmetric to be set up, hindering nature intracavity. The utility model discloses set up hindering nature chamber and resistance chamber asymmetrically on the inner wall of noise elimination case for the inner wall that the noise elimination case is relative can carry out hindering nature noise elimination and resistance noise elimination simultaneously, thereby improves noise elimination effect.

Description

Impedance combined type fan silencing box
Technical Field
The utility model belongs to the technical field of the technique of equipment of making an uproar falls in the noise elimination and specifically relates to an impedance combined type fan noise elimination case is related to.
Background
The fan is a ventilating device widely used in air conditioning systems of buildings, mainly converts mechanical energy into gas pressure energy and kinetic energy through the rotation of an impeller, and discharges gas. The noise generated during the operation of the fan is often greater than the noise standard required for the building environment, so the fan needs to be muffled and denoised to meet the environmental noise standard.
The existing fan noise elimination method mainly adopts a fan silencer, and comprises a resistive silencer with a good noise elimination effect on medium-frequency and high-frequency noises and a reactive silencer with a good noise elimination effect on low-frequency and medium-frequency noises. In the actual noise control engineering, noise is mostly broadband, and the noise elimination principle of the resistive muffler and the reactive muffler is combined into an impedance composite muffler through a proper structure so as to control high-strength broadband noise.
The impedance composite muffler mainly has a circular structure and a rectangular structure. The existing impedance type silencer is generally designed in a symmetrical mode, namely a resistive silencing area is opposite to the resistive silencing area, and the resistive silencing area is opposite to the resistive silencing area, so that one section of the existing impedance type silencer is mainly used for resistive silencing, the other section of the existing impedance type silencer is mainly used for resistive silencing, and the silencing effect is not good.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing an impedance combined type fan noise elimination case sets up hindering nature cavity and resistance resonant cavity asymmetrically on the inner wall of sound insulation case for the inner wall that the noise elimination case is relative can carry out hindering nature noise elimination and resistance noise elimination simultaneously, thereby improves noise elimination effect.
The above utility model discloses an above-mentioned utility model purpose can realize through following technical scheme:
the utility model provides an impedance combined type fan noise elimination case, includes cavity both ends open-ended case shell, wherein one end of well kenozooecium length direction is the air inlet in the case shell, and the other end is the gas outlet, the case shell includes outside outer casing and is located the inside inner box shell that matches with outer casing shape of outer casing, leaves the space vacuole formation between inner box shell and the outer casing, and inner box shell and outer casing length direction's both ends utilize the fixed plate to connect respectively, are provided with a plurality of through-holes that run through the inner box shell on the inner box shell, be provided with a plurality of baffles of cutting apart the cavity along the length direction of case shell in the cavity, a plurality of resistance chambeies and a plurality of hindering nature chamber are cut apart into with the cavity to the baffle, resistance chamber and the asymmetrical setting in hindering nature intracavity packing have sound absorbing material.
By adopting the technical scheme, the noise generated by the fan is subjected to broadband noise elimination by utilizing asymmetric resistance noise elimination and resistance noise elimination principles, so that the noise elimination effect is improved.
The utility model discloses further set up to: and a plurality of partition plates are arranged in the resistance cavity at intervals along the length direction of the box shell.
Through adopting above-mentioned technical scheme, set up the resistance chamber along the length direction of case shell and cut apart into the little resistance chamber of multistage for well low frequency noise is in narrow and small space multiple reflection, thereby improves noise elimination effect.
The utility model discloses further set up to: the baffle is including being located the first baffle that interior casing four corners level stretches out to outer casing and the vertical second baffle that stretches out to outer casing, set up a plurality of through-holes that run through the face on first baffle and the second baffle respectively.
Through adopting above-mentioned technical scheme, cut apart four resistance chambeies and communicate with adjacent resistance chamber and resistance chamber with the four corners of case shell to can handle the noise that comes from adjacent anechoic chamber, improve the treatment effect.
The utility model discloses further set up to: the sound absorption material is a centrifugal glass wool felt.
By adopting the technical scheme, the glass wool is made of porous materials, so that the sound absorption performance is good, and the cost is low.
The utility model discloses further set up to: and the upper surface of the bottom end of the inner box shell is horizontally provided with a mounting frame fixedly connected with the box shell.
Through adopting above-mentioned technical scheme, set up the mounting bracket on the case shell, conveniently install the fan.
The utility model discloses further set up to: the outer box shell comprises a first outer box shell positioned on the upper part and a second outer box shell positioned on the lower part, the inner box shell comprises a first inner box shell positioned on the upper part and a second inner box shell positioned on the lower part, the bottom ends of the first outer box shell and the first inner box shell are positioned on the same plane and fixedly connected through a first sealing plate, and the top ends of the second outer box shell and the second inner box shell are positioned on the same plane and fixedly connected through a second sealing plate; first outer case shell and second outer case shell can dismantle the connection.
Through adopting above-mentioned technical scheme, when the fan of the inside of box that disappears needs overhauls, only need with the upper portion of silencing case pull down can, need not pull down silencing case is whole.
The utility model discloses further set up to: the bottom ends of two opposite side walls in the width direction of the first outer case are provided with first folded plates which are outwards ejected, the top ends of two opposite side walls in the width direction of the second outer case are provided with second folded plates which are outwards extended, are opposite to the first folded plates and are matched with the first folded plates in shape, and the first folded plates and the second folded plates are fixedly connected through bolts.
Through adopting above-mentioned technical scheme, utilize bolted connection to realize being connected dismantled of first outer box shell and second outer box shell.
The utility model discloses further set up to: flanges are fixedly connected to the two ends of the box shell in the length direction.
Through adopting above-mentioned technical scheme, make things convenient for being connected of noise reduction box and other equipment.
The utility model discloses further set up to: the position of the air inlet of the box shell is provided with a hollow protective cover detachably connected with the flange.
Through adopting above-mentioned technical scheme, when the fan was arranged in outdoor being used for the ventilation, avoided having the foreign matter to cause the damage to the fan and get into the inside pipeline through the noise elimination case in the in-process of air inlet gets into the noise elimination incasement.
To sum up, the utility model discloses a beneficial technological effect does:
1. the resistance silencing cavity and the resistance silencing cavity are asymmetrically arranged on the side wall of the silencing box, so that resistance silencing and resistance silencing can be simultaneously carried out on any section of the silencing box in the extension direction, and the silencing effect of the fan is improved;
2. through setting up the noise elimination case into upper and lower detachable two parts, be air pipe in noise elimination case both sides and the fan need overhaul under the condition, only need open the upper portion of noise elimination case alright to make the maintenance of fan more convenient.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention;
fig. 2 is a schematic sectional structure of the present invention;
fig. 3 is a cross-sectional view of the present invention;
fig. 4 is another cross-sectional view of the present invention;
fig. 5 is a cross-sectional view in another direction of the present invention;
fig. 6 is a schematic structural view after the blower and the protective cover are installed.
In the figure, 1, a box shell; 101. a first enclosure; 1011. a first outer case; 1012. a first inner box shell; 1013. a first folded plate; 102. a second enclosure; 1021. a second outer box housing; 1022. a second inner housing; 1023. a second folded plate; 103. a first fixing plate; 104. a second fixing plate; 105. a first separator; 106. a second separator; 107. a third partition plate; 108. a fourth separator; 109. a fifth partition plate; 110. a first seal plate; 111. a second seal plate; 2. an air inlet; 3. an air outlet; 4. a first flange; 5. a second flange; 6. a first resistance chamber; 7. a second resistant chamber; 8. a third resistance chamber; 9. a fourth resistance chamber; 10. a first resistive cavity; 11. a second resistive cavity; 12. a third resistive cavity; 13. a sound absorbing material; 14. a mounting frame; 15. a fan; 16. a protective cover; 17. and (7) a rubber pad.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 1 and 2, an impedance fan muffling box according to the present invention includes a hollow box casing 1 with openings at both ends, an air inlet 2 at the front end of the box casing 1, and an air outlet 3 at the rear end of the box casing 1.
The box shell 1 is divided into two parts which are mirror symmetrical up and down, and comprises a first box shell 101 which is in an inverted U shape at the upper part and a second box shell 102 which is in a U shape at the lower part. The U-shaped openings of the first casing 101 and the second casing 102 are opposed to and communicate with each other.
The first housing 101 includes an outer inverted U-shaped first outer housing 1011 and a first inner housing 1012 located inside the first outer housing 1011 and matching the shape of the first outer housing 1011. A gap is left between the first outer case 1011 and the first inner case 1012. The two ends of the first outer case 1011 and the first inner case 1012 in the length direction are located on the same plane and fixedly connected by the first fixing plate 103; the bottom ends of the first outer case 1011 and the first inner case 1012 are located at the same horizontal plane and fixedly connected by the first cover plate 110. The first inner casing 1012 is provided with a plurality of through holes penetrating the panel surface.
The first partition 105 horizontally extending toward the first outer case 1011 and the second partition 106 vertically extending toward the first outer case 1011 are provided at two corners in the width direction of the top surface of the first inner case 1012, respectively. The first partition plate 105 and the second partition plate 106 are fixedly connected to the first outer case 1011 and the first inner case 1012 by two first fixing plates 103 facing each other. A plurality of through holes penetrating the plate surface are formed in the first partition plate 105 and the second partition plate 106.
With the above arrangement, the space between the first outer case 1011 and the first inner case 1012 is divided into a plurality of cavities. The space between the two opposing second partitions 106 on the upper part of the first housing 101, the first inner housing 1012 and the first outer housing 1011 is the first resistance chamber 6. The space between the first partition 105, the first cover plate 110, the first outer housing 1011 and the first inner housing 1012 on the left side of the first housing 101 is a third resistive cavity 12, and the third resistive cavity 12 is filled with a sound absorbing material 13. The space between the first partition 105, the first cover plate 110, the first outer housing 1011 and the first inner housing 1012 on the right side of the first housing 101 is the second resistance chamber 7. The space between the first partition 105 and the second partition 106 at the two ends of the first resistance chamber 6 in the width direction, the first outer case 1011 opposite to the first partition 105, and the first outer case 1011 opposite to the second partition 106 is the fourth resistance chamber 9. The first resistance cavity 6 is respectively communicated with two opposite fourth resistance cavities 9, the fourth resistance cavity 9 on the left side is communicated with the third resistance cavity 12, and the fourth resistance cavity 9 on the right side is communicated with the second resistance cavity 7.
Referring to fig. 4 and 5, the second reactive chamber 7 is provided with fourth partitions 108 at intervals along the length direction, and the fourth partitions 108 are provided in two and divide the second reactive chamber 7 into three. The fourth partition 108 is fixedly connected to the first outer case 1011, the first inner case 1012, the first partition 105 and the first cover plate 110. Fifth partition plates 109 are provided at intervals in the first resistance chamber 6 in the longitudinal direction, and the fifth partition plates 109 are provided in two and trisect the first resistance chamber 6. The fifth partition 109 is fixedly connected to the first outer case 1011, the first inner case 1012, and the second partition 106, respectively.
The second casing 102 includes a second outer casing 1021 of an outer U-shape and a second inner casing 1022 located inside the second outer casing 1021 and matching the shape of the second outer casing 1021. A space is left between the second outer case 1021 and the second inner case 1022. The two ends of the second outer casing 1021 and the second inner casing 1022 in the length direction are located on the same plane and fixedly connected by the second fixing plate 104; the top ends of the second outer case 1021 and the second inner case 1022 are located at the same horizontal plane and are fixedly connected by the second closing plate 111. The second inner case 1022 has a plurality of through holes formed through the board surface.
The first partition 105 horizontally extending toward the second outer casing 1021 and the second partition 106 vertically extending toward the second outer casing 1021 are provided at two corners in the width direction of the bottom surface of the second inner casing 1022, respectively. The first partition plate 105 and the second partition plate 106 are fixedly connected to the second outer case 1021, the second inner case 1022, and the two opposing second fixing plates 104, respectively. A plurality of through holes penetrating the plate surface are formed in the first partition plate 105 and the second partition plate 106.
With the above arrangement, the space between the second outer case 1021 and the second inner case 1022 is divided into a plurality of cavities. The space between the two opposite second partition plates 106 at the lower part of the second enclosure 102, the second inner enclosure 1022 and the second outer enclosure 1021 is a first resistive cavity 10, and the sound-absorbing material 13 is filled in the first resistive cavity 10. The space between the first bulkhead 105, the second closure plate 111, the second outer enclosure 1021, and the second inner enclosure 1022 on the left side of the second enclosure 102 is the third resistance chamber 8. The space between the first partition 105, the second closing plate 111, the second outer box shell 1021 and the second inner box shell 1022 on the right side of the second box shell 102 is a second resistive cavity 11, and the second resistive cavity 11 is filled with a sound absorbing material 13. And a space surrounded by the first partition plate 105, the second partition plate 106, the second outer case 1021 opposite to the first partition plate 105 and the second outer case 1021 opposite to the second partition plate 106 at two ends of the first resistive cavity 10 in the width direction is a fourth resistive cavity 9. The first resistive cavity 10 is respectively communicated with the two opposite fourth resistive cavities 9, the left fourth resistive cavity 9 is communicated with the third resistive cavity 8, and the right fourth resistive cavity 9 is communicated with the second resistive cavity 11.
Referring to fig. 3, third partitions 107 are provided at intervals in the third resistance chamber 8 along the length direction, and the third partitions 107 are provided in two and trisect the third resistance chamber 8. The third partition 107 is fixedly connected to the second outer case 1021, the second inner case 1022, the first partition 105, and the second cover plate 111, respectively.
The bottom ends of two opposite side walls in the width direction of the first outer case 1011 are provided with first flaps 1013 extending outward. The bottom surface of the first folding plate 1013 is located at the same level as the bottom surface of the first cover plate 110. The top ends of two opposite side walls in the width direction of the second outer case 1021 are provided with a second folding plate 1023 which extends outwards and is opposite to the first folding plate 1013 and is matched with the first folding plate 1013 in shape. The top surface of the second flap 1023 is at the same level as the top surface of the second cover plate 111. The first flap 1013 is fixedly connected to the first outer case 1011, and the second flap 1023 is fixedly connected to the second outer case 1021. The first flap 1013 and the second flap 1023 are fixedly connected by bolts. A rubber pad 17 is disposed between the first flap 1013 and the second flap 1023. The first outer case 1011 and the second outer case 1021 constitute an outer case relatively, and the first inner case 1021 and the second outer case 1022 constitute an inner case relatively.
With the above arrangement, the first resistive cavity 6 is opposite to the first resistive cavity 10, the second resistive cavity 7 is opposite to the third resistive cavity 12, and the third resistive cavity 8 is opposite to the second resistive cavity 11. The sound absorbing materials 13 filled in the first resistive cavity 10, the second resistive cavity 11 and the third resistive cavity 12 are all made of centrifugal glass wool felt.
The resistance cavity and the resistance cavity are arranged oppositely, so that noise can be subjected to resistance noise elimination and resistance noise elimination at the same stage in the length direction of the noise elimination box, and the noise subjected to the resistance noise elimination and the resistance noise elimination can mutually generate in the opposite noise treatment cavity to be subjected to complementary noise elimination of different frequency bands, so that the noise treatment effect is improved.
The first reactive cavity 6, the second reactive cavity 7 and the third reactive cavity 8 are respectively divided into a plurality of sections along the length direction, so that the medium and low frequency noise is reflected for a plurality of times in a narrow space, and the noise elimination effect is improved.
The fourth reactive cavities 9 positioned at the four corners of the silencing box can respectively process the noise processed by the reactive cavities and the resistive cavities adjacent to the fourth reactive cavities, so that the space of the silencing box is fully utilized, and the noise processing effect is improved.
Referring to fig. 1 and 2, a mounting rack 14 is horizontally disposed on the upper surface of the bottom end of the second inner case 1022, the mounting rack 14 includes two section steels disposed along the width direction of the case 1, and the section steels are fixedly connected to the second case 102. A fan 15 is mounted on the mounting frame 14. The fan 15 is bolted to the mounting bracket 14. After the fan 15 is started, the sound absorption material 13 and the resistance cavity in the resistance cavity asymmetrically arranged on the box shell 1 respectively reduce the noise generated by the fan 15, so that the fan 15 is muffled.
Referring to fig. 1 and 6, an inverted U-shaped first flange 4 fixedly connected to the first casing 101 and a U-shaped second flange 5 fixedly connected to the second casing 102 and opposed to the first flange 4 are provided at both ends of the casing 1 in the longitudinal direction, and the opposed surfaces of the first flange 4 and the second flange 5 are in contact with each other and are mirror-symmetrical with respect to the contact surface.
The flange is used to connect the muffling tank to other equipment in the ventilation duct. Set case shell 1 to detachable upper and lower two parts, conveniently directly open first case shell 101 in narrow and small space and overhaul the fan, need not pull down the noise elimination case is whole.
A hollow protective cover 16 is arranged on a flange positioned at the air inlet 2 at the front end of the box shell 1, and the protective cover 16 is connected with the flange through bolts. The protective cover 16 is used for protecting the fan 15 from foreign matters entering the inside of the box shell 1 to damage the fan 15 in the using process.
The implementation principle of the embodiment is as follows: the fan 15 is first mounted to the mounting bracket 14, after which the first housing 101 is bolted to the second housing 102. In the operation process of the fan 15, the sound absorption material 13 and the resistant cavity in the resistant cavity of the fan silencing box are used for silencing the noise generated by the fan 15.
The utility model discloses a resistive cavity and resistance chamber of asymmetric setting on the inner wall of fan noise elimination case for the inner wall that the noise elimination case is relative can carry out resistive noise elimination and resistance noise elimination simultaneously, can be in order to carry out the wide band noise elimination. The medium-high frequency noise which is not eliminated in the resistance cavity is reflected to reach the opposite resistance cavity and is eliminated by the sound absorption material 13; the medium and low frequency noise which is not eliminated by the sound absorption material 13 in the resistive cavity is reflected into the opposite resistive cavity to be eliminated, so that the noise elimination effect of the noise elimination box is improved.
The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims (9)

1. The utility model provides an impedance combined type fan noise elimination case, includes cavity both ends open-ended case shell (1), well wherein one end of well kenozooecium length direction is air inlet (2) in case shell (1), and the other end is gas outlet (3), case shell (1) includes outside outer shell and is located the inner box shell that outer shell inside and match with outer shell shape, leaves space vacuole formation between inner box shell and the outer shell, and inner box shell and outer shell length direction's both ends utilize the fixed plate to connect respectively, are provided with a plurality of through-holes that run through inner box shell on the inner box shell, its characterized in that: the novel cabinet is characterized in that a plurality of partition plates for dividing the cavity are arranged in the cavity along the length direction of the cabinet shell, the cavity is divided into a plurality of resistant cavities and a plurality of resistive cavities by the partition plates, the resistant cavities and the resistive cavities are arranged asymmetrically, and sound absorption materials (13) are filled in the resistive cavities.
2. The impedance compound fan muffling box of claim 1, wherein: a plurality of partition plates are arranged in the resistance cavity at intervals along the length direction of the box shell (1).
3. The impedance compound fan muffling box of claim 1, wherein: the baffle is including being located first baffle (105) that interior casing four corners level stretches out to outer casing and vertical second baffle (106) that stretch out to outer casing, set up a plurality of through-holes that run through the face on first baffle (105) and second baffle (106) respectively.
4. The impedance compound fan muffling box of claim 1, wherein: the sound absorption material (13) is a centrifugal glass wool felt.
5. The impedance compound fan muffling box of claim 1, wherein: and the upper surface of the bottom end of the inner box shell is horizontally provided with a mounting rack (14) fixedly connected with the box shell (1).
6. The impedance compound fan muffling box of claim 5, wherein: the outer case includes a first outer case (1011) at an upper portion and a second outer case (1021) at a lower portion, and the inner case includes a first inner case (1012) at an upper portion and a second inner case (1022) at a lower portion; the bottom ends of the first outer box shell (1011) and the first inner box shell (1012) are positioned on the same plane and fixedly connected by a first sealing plate (110), and the top ends of the second outer box shell (1021) and the second inner box shell (1022) are positioned on the same plane and fixedly connected by a second sealing plate (111); the first outer case shell (1011) and the second outer case shell (1021) are detachably connected.
7. The impedance compound fan muffling box of claim 6, wherein: the bottom ends of two opposite side walls in the width direction of the first outer case shell (1011) are provided with a first folded plate (1013) which is ejected outwards, the top ends of two opposite side walls in the width direction of the second outer case shell (1021) are provided with a second folded plate (1023) which extends outwards, is opposite to the first folded plate (1013) and is matched with the shape of the first folded plate, and the first folded plate (1013) and the second folded plate (1023) are fixedly connected by bolts.
8. The impedance compound fan muffling box of claim 1, wherein: flanges are fixedly connected to the two ends of the box shell (1) in the length direction.
9. The impedance compound fan muffling box of claim 1, wherein: the air inlet (2) of the box shell (1) is provided with a hollow protective cover (16) detachably connected with the flange.
CN201922191858.1U 2019-12-07 2019-12-07 Impedance combined type fan silencing box Active CN211288264U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201922191858.1U CN211288264U (en) 2019-12-07 2019-12-07 Impedance combined type fan silencing box

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201922191858.1U CN211288264U (en) 2019-12-07 2019-12-07 Impedance combined type fan silencing box

Publications (1)

Publication Number Publication Date
CN211288264U true CN211288264U (en) 2020-08-18

Family

ID=72034225

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201922191858.1U Active CN211288264U (en) 2019-12-07 2019-12-07 Impedance combined type fan silencing box

Country Status (1)

Country Link
CN (1) CN211288264U (en)

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