CN216430077U - Composite silencing box of axial flow fan - Google Patents
Composite silencing box of axial flow fan Download PDFInfo
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- CN216430077U CN216430077U CN202123036971.6U CN202123036971U CN216430077U CN 216430077 U CN216430077 U CN 216430077U CN 202123036971 U CN202123036971 U CN 202123036971U CN 216430077 U CN216430077 U CN 216430077U
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Abstract
The application concretely relates to axial fan's compound noise elimination case belongs to the axial fan field, includes: the sound insulation box body is used for covering the outer part of the axial flow fan and is provided with an air inlet hole and an air outlet hole; the active noise elimination assembly is used for actively reducing noise of the air inlet holes and/or the air outlet holes and arranged on the air inlet holes and/or the air outlet holes. The active noise elimination assembly is arranged at the air inlet hole and/or the air outlet hole of the sound insulation box body, the active noise elimination assembly emits compensation infrasound, and the compensation infrasound and noise at the air inlet hole and/or the air outlet hole are subjected to interference noise elimination, so that the noise at the air inlet hole and/or the air outlet hole is greatly reduced, the transmission of fan noise through a pipeline air flow channel is further inhibited, and the noise transmitted to the outside through an inlet air channel and an outlet air channel is finally controlled.
Description
Technical Field
The application relates to the field of axial flow fans, in particular to a composite silencing box of an axial flow fan.
Background
In the fields of ships, boats and the like, for working cabins or living cabins without power equipment, cabin air noise is mainly generated by an air conditioner and a ventilation system, and has important influence on the work, life and even physical and psychological health of personnel. In order to ensure that the working and living environment of personnel is quiet and comfortable as much as possible, the air noise inside the cabin needs to be controlled, and the air conditioner and the equipment and pipelines of a ventilation system are the key points of control.
Axial flow fans are a common air conditioning ventilation device and are widely used due to small volume and large air volume. For noise control of an axial flow fan, a fan sound insulation cover is usually adopted to cover the axial flow fan, and a certain sound insulation effect is achieved in a closed or semi-closed mode. However, the traditional sound insulation cover can only reduce the noise radiated by the fan itself to the outside, and the noise transmitted to the outside through the inlet and outlet air ducts cannot be controlled, so that the whole sound insulation effect is limited.
SUMMERY OF THE UTILITY MODEL
The application provides a compound noise elimination case of axial fan to solve the technical problem that the noise that prior art's sound proof cover can't control passes through the external transmission of import and export wind channel.
The application provides compound noise elimination case of axial fan, include:
the sound insulation box body is used for covering the outer part of the axial flow fan and is provided with an air inlet hole and an air outlet hole;
the active noise elimination assembly is used for actively reducing noise of the air inlet holes and/or the air outlet holes and is arranged in the air inlet holes and/or the air outlet holes.
Optionally, the active muffler assembly includes:
the error microphone is used for collecting noise signals, and the collecting end of the error microphone extends into the air inlet hole and/or the air outlet hole;
a filter to compute a noise signal and output a secondary sound source signal, the filter in communication with the error microphone;
a power amplifier to amplify a secondary source signal, the power amplifier in communication with the filter;
the loudspeaker is used for emitting compensation infrasound and carrying out interference noise elimination on noise, faces towards the air inlet hole and/or the air outlet hole and is in communication connection with the power amplifier.
Optionally, a noise elimination ring is arranged in each of the air inlet and the air outlet, and the acquisition end of the error microphone penetrates through the noise elimination ring to be arranged in the noise elimination ring.
Optionally, flanges are respectively arranged at two ends of the silencing ring, one end of the silencing ring is connected with the air inlet or the air outlet of the axial flow fan through the flange, and the other end of the silencing ring is connected with the ventilation pipeline through the flange.
Optionally, rubber pads are arranged between the silencing ring and the air inlet hole and between the silencing ring and the air outlet hole.
Optionally, the inside of the sound insulation box body is matched with the appearance of the axial flow fan, and a through hole is formed in the top of the sound insulation box body and used for being matched with a mounting base of the axial flow fan.
Optionally, the sound insulation box body comprises a first sound insulation block, a second sound insulation block and a sound insulation bottom cover, the first sound insulation block and the second sound insulation block are symmetrically arranged about a vertical plane where a central shaft of the air inlet hole is located, the sound insulation bottom cover is arranged at the bottom of the first sound insulation block and the bottom of the second sound insulation block, the first sound insulation block and the second sound insulation block are detachably connected, and the sound insulation bottom cover is detachably connected with the first sound insulation block and the second sound insulation block respectively.
Optionally, the first sound insulation block and the second sound insulation block are connected through a folded edge hasp, the first sound insulation block and the sound insulation bottom cover are connected through a folded edge hasp, and the second sound insulation block and the sound insulation bottom cover are connected through a folded edge hasp.
Optionally, the top surface of the sound insulation box body is provided with an installation leg, the installation leg is an L-shaped angle steel, one end of the installation leg is embedded in the sound insulation box body, and the other end of the installation leg is provided with a threaded hole.
Optionally, a sound attenuation material is arranged inside the wall of the sound insulation box body.
Compared with the prior art, the technical scheme provided by the embodiment of the application has the following advantages:
according to the embodiment of the application, the active noise elimination assembly is arranged at the air inlet hole and/or the air outlet hole of the sound insulation box body, the active noise elimination assembly emits compensation infrasound, and the compensation infrasound and noise at the air inlet hole and/or the air outlet hole are interfered to eliminate noise, so that the noise at the air inlet hole and/or the air outlet hole is greatly reduced, further, the transmission of fan noise through a pipeline airflow channel is inhibited, and finally, the noise transmitted to the outside through the inlet and outlet air channels is controlled.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor.
Fig. 1 is a schematic perspective view of a composite muffling box of an axial flow fan according to an embodiment of the present disclosure;
FIG. 2 is a front view of a stack provided by an embodiment of the present application;
fig. 3 is a schematic cross-sectional structure diagram of a stack provided in an embodiment of the present application.
Reference numerals:
1-sound insulation box body, 11-air inlet hole, 12-air outlet hole, 13-noise elimination ring, 131-rubber pad, 132-flange, 14-through hole, 15-first sound insulation block, 151-first folding edge, 152-second folding edge, 16-second sound insulation block, 161-first hasp, 162-third hasp, 17-sound insulation bottom cover, 171-second hasp, 172-third folding edge, 18-installation machine foot and 19-noise elimination material;
2-active noise elimination component, 21-error microphone, 22-filter, 23-power amplifier, 24-loudspeaker and 25-power supply.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In ships and warships, because air conditioners, ventilation systems and the like are usually arranged at the top of a space, an axial flow fan is usually arranged on a ceiling through a mounting base and is provided with an air inlet and an air outlet, the air inlet and the air outlet are both connected with ventilation pipelines, the axial flow fan generates great noise due to the vibration of a motor in the axial flow fan and the impact of airflow on the air inlet and the air outlet, and the noise is harmful to human bodies.
As shown in fig. 1 to 3, a composite muffling box of an axial flow fan includes:
the sound insulation box body 1 is used for covering the outer part of the axial flow fan, the sound insulation box body 1 is provided with an air inlet hole 11 and an air outlet hole 12, the air inlet hole 11 corresponds to an air inlet of the axial flow fan, and the air outlet hole 12 corresponds to an air outlet of the axial flow fan;
the active noise elimination assembly 2 is used for actively reducing noise of the air inlet hole 11 and/or the air outlet hole 12, and the active noise elimination assembly 2 is arranged on the air inlet hole 11 and/or the air outlet hole 12.
In the embodiment of the application, the air inlet 11 and the air outlet 12 are both provided with the active noise elimination assembly 2, the active noise elimination assembly 2 is arranged on the air inlet 11 and/or the air outlet 12 of the sound insulation box body 1, the active noise elimination assembly 2 emits the compensation infrasound, and the compensation infrasound interferes with the noise at the air inlet 11 and/or the air outlet 12 for noise elimination, so that the noise at the air inlet 11 and/or the air outlet 12 is greatly reduced, further, the transmission of the fan noise through a pipeline airflow channel is inhibited, and finally, the noise transmitted to the outside through the inlet and outlet air channels is controlled.
In some embodiments, the active muffler assembly 2 comprises:
the error microphone 21 is used for collecting noise signals, and the collecting end of the error microphone 21 extends into the air inlet hole 11 and/or the air outlet hole 12;
a filter 22 for computing a noise signal and outputting a secondary sound source signal, said filter 22 being communicatively connected to said error microphone 21;
a power amplifier 23, said power amplifier 23 configured to amplify a secondary source signal, said power amplifier 23 communicatively coupled to said filter 22;
the loudspeaker 24 is used for emitting compensation infrasound and carrying out interference noise elimination on noise, the loudspeaker 24 faces the air inlet hole 11 and/or the air outlet hole 12, and the loudspeaker 24 is in communication connection with the power amplifier 23.
In the embodiment of the application, the active noise elimination assembly 2 further comprises a power supply 25, the power supply 25 is electrically connected with the error microphone 21, the filter 22, the power amplifier 23 and the loudspeaker 24, the error microphone 21, the filter 22, the power amplifier 23 and the loudspeaker 24 are connected through cables, and the error microphone 21, the filter 22, the power amplifier 23 and the power supply 25 are arranged on the end face of the sound insulation box body 1.
After the error microphone 21 collects the noise signal, the noise signal is transmitted to the filter 22, the filter 22 analyzes the noise signal and outputs a secondary sound source signal with a waveform opposite to that of the noise signal, the secondary sound source signal is amplified by the power amplifier 23 and then transmitted to the loudspeaker 24, the loudspeaker 24 plays a compensation infrasound with a waveform opposite to that of the noise, the compensation infrasound and the noise are mutually interfered and cancelled at the air inlet hole 11 and the air outlet hole 12, and the mechanical energy of the noise and the compensation infrasound is converted into the air internal energy, so that the noise of the air inlet hole 11 and the air outlet hole is eliminated.
In some embodiments, a noise elimination ring 13 is disposed in each of the air inlet 11 and the air outlet 12, the collection end of the error microphone 21 passes through the noise elimination ring 13 and is disposed in the noise elimination ring 13, and in this embodiment, a rubber pad 131 is disposed between the noise elimination ring 13 and each of the air inlet 11 and the air outlet 12.
The noise elimination ring 13 is arranged, so that the error microphone 21 can be conveniently installed, and meanwhile, the inlet channel and the outlet channel of the airflow can be partially extended, so that the acquisition end of the error microphone 21 is positioned at a position where the airflow is relatively stable, and the noise signal acquired by the acquisition end of the error microphone 21 is more accurate; in addition, as the sound insulation box body 1 slightly vibrates under the driving of the vibration of the axial flow fan, if the noise elimination ring 13 is directly connected with the sound insulation box body 1, the noise elimination ring 13 also synchronously vibrates with the sound insulation box body 1, and further the noise collected by the error microphone 21 is influenced, and the rubber pads 131 arranged between the noise elimination ring 13 and the air inlet hole 11 and between the noise elimination ring 13 and the air outlet hole 12 can eliminate the error caused by the vibration of the sound insulation box body 1, so that the noise signal collected by the error microphone 21 is more accurate.
In some embodiments, flanges 132 are disposed at two ends of the sound-deadening ring 13, one end of the sound-deadening ring 13 is connected to an air inlet or an air outlet of the axial flow fan through the flange 132, the other end of the sound-deadening ring 13 is connected to the ventilation duct through the flange 132, and the sound-deadening ring 13 is connected to the ventilation duct more stably by the flange 132, so as to prevent the air leakage of the axial flow fan.
In some embodiments, the inside of the sound insulation box body 1 is matched with the shape of the axial flow fan, the top of the sound insulation box body 1 is provided with a through hole 14, the through hole 14 is used for being matched with a mounting base of the axial flow fan, the sound insulation box body 1 is adaptively designed according to the shapes of the axial flow fan and the fan base, the shape minimization is ensured, and the sound insulation box body is adaptable to narrow mounting spaces such as naval vessels and ships.
In some embodiments, the sound insulation box 1 includes a first sound insulation block 15, a second sound insulation block 16, and a sound insulation bottom cover 17, the first sound insulation block 15 and the second sound insulation block 16 are symmetrically disposed about a vertical plane where a central axis of the air inlet 11 is located, the sound insulation bottom cover 17 is disposed at bottoms of the first sound insulation block 15 and the second sound insulation block 16, the first sound insulation block 15 and the second sound insulation block 16 are detachably connected, and the sound insulation bottom cover 17 is detachably connected to the first sound insulation block 15 and the second sound insulation block 16, respectively.
In the embodiment of the application, the shape enclosed by the first sound insulation block 15 and the second sound insulation block 16 is a cuboid, the sound insulation bottom cover 17 is a semi-cylindrical shape, and the top surface of the sound insulation bottom cover 17 is connected with the bottom surfaces of the first sound insulation block 15 and the second sound insulation block 16 to jointly enclose a sound attenuation space for accommodating the axial flow fan and the mounting base thereof. The detachable connection can be through a screw connection or a folded edge snap connection.
The sound insulation box body 1 is designed in a partitioning mode, and the partitions are connected through the folded edge buckles or the screws, so that the sound insulation box body is convenient to mount and dismount; meanwhile, in order to avoid the assembly difficulty caused by too many blocks, the maximization principle is adopted for the blocks, and the blocks are only divided into three modules as required, so that the assembly and disassembly are simple and convenient.
In some embodiments, the first sound insulation block 15 and the second sound insulation block 16 are connected by a folded-edge snap, the first sound insulation block 15 and the sound insulation bottom cover 17 are connected by a folded-edge snap, and the second sound insulation block 16 and the sound insulation bottom cover 17 are connected by a folded-edge snap.
In the embodiment of the application, the folding buckles are arranged on two end faces of the sound insulation box body 1, wherein a first folding edge 151 is respectively arranged on the edge, close to the second sound insulation block 16, of the two end faces of the first sound insulation block 15, a second folding edge 152 is arranged on the edge, close to the sound insulation bottom cover 17, of the two end faces of the second sound insulation block 16, a first buckle 161 corresponding to the first folding edge 151 is respectively arranged on the edge, close to the first sound insulation block 15, of the two end faces of the second sound insulation block 16, a third buckle 162 is arranged on the edge, close to the sound insulation bottom cover 17, of the two end faces of the sound insulation bottom cover 17, a second buckle 171 is arranged on the edge, close to the second sound insulation block 16, and a third folding edge 172 is arranged on the edge, close to the second sound insulation block 16. So set up for when connecting into sound insulation box 1 with first sound insulation piece 15, second sound insulation piece 16 and sound insulation bottom 17 combination, it is more convenient.
In some embodiments, the top surface of the sound insulation box body 1 is provided with an installation leg 18, the installation leg 18 is an L-shaped angle steel, one end of the installation leg is embedded in the sound insulation box body 1, and the other end of the installation leg is provided with a threaded hole. In this embodiment, the mounting base of the axial flow fan is provided with a connecting piece matched with the mounting feet 18, so that the sound insulation box body 1 is more convenient to mount.
In some embodiments, a sound-absorbing material 19 is disposed inside the wall of the sound-insulating box 1, and by disposing the sound-absorbing material 19, the noise-absorbing capacity of the sound-insulating box 1 for the noise generated when the axial flow fan vibrates is enhanced, and the noise of the axial flow fan is further reduced.
In the embodiment of the application, when the sound insulation box body 1 is installed, firstly, the first sound insulation block 15 is covered in from the side surface of the axial flow fan, so that a half opening of the first sound insulation block 15 belonging to the through hole 14 is opened on the installation base of the axial flow fan, then, the installation machine foot 18 at the top of the first sound insulation block 15 is connected with the installation base, then, the second sound insulation block 16 is installed in the same way, so that the first sound insulation block 15 and the second sound insulation block 16 are folded, and then, the first folding edge 151 and the second buckle 171 are connected together, so that the first sound insulation block 15 and the second sound insulation block 16 are fixed; then, the rubber gasket 131 is clamped on the outer peripheral side of the sound attenuation ring 13, the flanges 132 at the end parts of the two sound attenuation rings 13 are connected with the air inlet and the air outlet of the axial flow fan, the sound insulation bottom cover 17 is abutted against the bottoms of the first sound insulation block 15 and the second sound insulation block 16, the second hasp 171 is buckled on the second folded edge 152, and the third hasp 162 is buckled on the third folded edge 172, so that the sound insulation box body 1 is installed; then, a power supply 25, a power amplifier 23 and a compensation filter 22 are installed on two end faces of the sound insulation box body 1 through bolts, then the error microphone 21 and the loudspeaker 24 are installed on the inner side of the sound attenuation ring 13, the error microphone 21, the compensation filter 22, the power amplifier 23 and the loudspeaker 24 are sequentially connected through cables, and finally the power supply 25 is connected into a circuit through the cables to supply power for other parts of the active sound attenuation component 2.
The embodiment of the application provides a novel active and passive composite muffling box for an axial flow fan in a working cabin or a living cabin of a naval vessel, has a sound insulation effect obviously superior to that of a traditional sound insulation cover, is small in space requirement and convenient to disassemble and assemble, meets the installation and use requirements of a spatial narrow cabin part on the naval vessel, and provides a good solution for controlling the air noise of the naval vessel cabin.
The above description is only exemplary of the invention, and is intended to enable those skilled in the art to understand and implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. The utility model provides a compound noise damping box of axial fan which characterized in that includes:
the sound insulation box body (1) is used for covering the outer part of the axial flow fan, and the sound insulation box body (1) is provided with an air inlet hole (11) and an air outlet hole (12);
the active noise elimination assembly (2) is used for actively eliminating noise of the air inlet holes (11) and/or the air outlet holes (12), and the active noise elimination assembly (2) is arranged on the air inlet holes (11) and/or the air outlet holes (12).
2. The composite muffling box of axial fan according to claim 1, wherein said active muffling assembly (2) comprises:
the error microphone (21) is used for collecting a noise signal, and the collecting end of the error microphone (21) extends into the air inlet hole (11) and/or the air outlet hole (12);
a filter (22) to compute a noise signal and output a secondary sound source signal, the filter (22) being communicatively connected to the error microphone (21);
a power amplifier (23), said power amplifier (23) to amplify a secondary source signal, said power amplifier (23) communicatively connected to said filter (22);
the loudspeaker (24) is used for emitting compensation infrasound and carrying out interference noise elimination on noise, the loudspeaker (24) faces the air inlet hole (11) and/or the air outlet hole (12), and the loudspeaker (24) is in communication connection with the power amplifier (23).
3. The composite muffling box of an axial flow fan according to claim 2, wherein muffling rings (13) are respectively arranged in the air inlet hole (11) and the air outlet hole (12), and the collection end of the error microphone (21) penetrates through the muffling rings (13) and is arranged in the muffling rings (13).
4. The composite muffling box of the axial flow fan according to claim 3, wherein flanges (132) are respectively disposed at two ends of the muffling ring (13), one end of the muffling ring (13) is connected to an air inlet or an air outlet of the axial flow fan through the flanges (132), and the other end of the muffling ring (13) is connected to a ventilation duct through the flanges (132).
5. The composite muffling box of an axial flow fan according to claim 3, wherein rubber pads (131) are arranged between the muffling ring (13) and the air inlet hole (11) and between the muffling ring and the air outlet hole (12).
6. The composite muffling box of an axial flow fan according to claim 1, wherein the inside of the sound-insulating box body (1) is matched with the shape of the axial flow fan, a through hole (14) is formed in the top of the sound-insulating box body (1), and the through hole (14) is used for being matched with a mounting base of the axial flow fan.
7. The composite sound-proof box of the axial flow fan is characterized in that the sound-proof box body (1) comprises a first sound-proof block (15), a second sound-proof block (16) and a sound-proof bottom cover (17), the first sound-proof block (15) and the second sound-proof block (16) are symmetrically arranged relative to a vertical plane where a central shaft of the air inlet hole (11) is located, the sound-proof bottom cover (17) is arranged at the bottoms of the first sound-proof block (15) and the second sound-proof block (16), the first sound-proof block (15) and the second sound-proof block (16) are detachably connected, and the bottom cover (17) is detachably connected with the first sound-proof block (15) and the second sound-proof block (16) respectively.
8. The composite sound-absorbing box of an axial flow fan according to claim 7, wherein the first sound-absorbing block (15) and the second sound-absorbing block (16) are connected by a folded edge snap, the first sound-absorbing block (15) and the sound-absorbing bottom cover (17) are connected by a folded edge snap, and the second sound-absorbing block (16) and the sound-absorbing bottom cover (17) are connected by a folded edge snap.
9. The composite muffling box of an axial flow fan according to claim 6, wherein the top surface of the sound-insulating box body (1) is provided with an installation machine leg (18), the installation machine leg (18) is an L-shaped angle steel, one end of the installation machine leg is embedded in the sound-insulating box body (1), and the other end of the installation machine leg is provided with a threaded hole.
10. The composite muffling box of an axial flow fan according to claim 1, wherein the sound-insulating box body (1) is provided with a muffling material (19) inside the wall thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123036971.6U CN216430077U (en) | 2021-12-06 | 2021-12-06 | Composite silencing box of axial flow fan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123036971.6U CN216430077U (en) | 2021-12-06 | 2021-12-06 | Composite silencing box of axial flow fan |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216430077U true CN216430077U (en) | 2022-05-03 |
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ID=81343255
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202123036971.6U Active CN216430077U (en) | 2021-12-06 | 2021-12-06 | Composite silencing box of axial flow fan |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216430077U (en) |
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2021
- 2021-12-06 CN CN202123036971.6U patent/CN216430077U/en active Active
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