CN204010667U - Broad-band strip-type silencer - Google Patents
Broad-band strip-type silencer Download PDFInfo
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- CN204010667U CN204010667U CN201420441019.5U CN201420441019U CN204010667U CN 204010667 U CN204010667 U CN 204010667U CN 201420441019 U CN201420441019 U CN 201420441019U CN 204010667 U CN204010667 U CN 204010667U
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Abstract
The utility model discloses a kind of broad-band strip-type silencer, it comprises anechoic sheet shell, by the perforation sound absorption panel of both sides, upper and lower cover plates and two ends end socket composition, the inner side of two perforation sound absorption panels is provided with certain thickness particulate acoustic board, between particulate acoustic board and perforation sound absorption panel, fill certain thickness acoustic absorbant and be made into absorbent treatment, acoustic absorbant adopts melamine or glass wool, between two particulate acoustic boards, be provided with dividing plate, dividing plate, particulate acoustic board and anechoic sheet shell surround certain thickness cavity, described cavity is only in communication with the outside by the open pore on particulate acoustic board, this cavity forms micropore resonance sound-absorbing structure as back of the body chamber, this sound suppressor is low, in, high band all has good sound absorbing capabilities, can keep the contour structures identical with conventional strip-type silencer, produce so that adopt original technique and production line.
Description
Technical field
The present invention relates to a kind of strip-type silencer.
Background technology
Strip-type silencer is widely used for eliminating the noises such as blower fan.Its structure is in muffler shell, to insert sound-absorbing porous material, and porosint generally adopts the inorganic material such as glass wool, super glass wool, rock wool.
Conventional resistive plate silencer shows good conventionally aspect medium-high frequency acoustic attenuation performance, but aspect low frequency acoustic attenuation performance, barely satisfactory, this is to be determined by the characteristic of sound-absorbing porous material.Therefore, how existing strip-type silencer being improved, make it have equally good low frequency absorption performance, is a comparatively popular at present research direction.
Microperforated panel soundabsorbing construction is a kind of simple in structure, and the sound absorption structure that sound absorbing capabilities is good can be by the sound absorption characteristics of the parameter change microperforated panel soundabsorbing constructions such as the aperture of adjusting microperforated panel, pitch-row, percentage of perforation, thickness of slab, cavity size.Microperforated panel soundabsorbing construction is a case structure, it comprises the microperforated panel towards sound source one side, microperforated panel is relative with the backboard that is generally rigid plate, surrounding is connected the two by side plate, it between microperforated panel and backboard, is the back of the body chamber at air layer place, on backboard, side plate, all without perforate, back of the body chamber only communicates with the external world via the hole on microperforated panel.Conventional microperforated panel wants to obtain in the low-frequency range below 500Hz good sound absorbing capabilities, can only select larger cavity, be that air layer thickness is thicker, more than need reaching 400mm, this is subject to larger restriction in actual applications, and because the sound sucting band of microperforated panel soundabsorbing construction is narrower, being conventionally no more than 2 octave bands, resonance sound-absorbing coefficient is lower.
Whether the structure of microperforated panel soundabsorbing construction and conventional resistive plate silencer can be carried out to organic assembling, thereby form a kind of broad-band strip-type silencer that all has better sound absorbing capabilities at basic, normal, high frequency.
Summary of the invention
For overcoming the deficiency of existing strip-type silencer low frequency absorption poor-performing, technical problem to be solved in the utility model is to provide a kind of broad-band strip-type silencer that all has better sound absorbing capabilities at basic, normal, high frequency.
The utility model solves the technical scheme that its technical matters adopts: broad-band strip-type silencer, comprise anechoic sheet shell, anechoic sheet shell comprises the perforation sound absorption panel of both sides, the inner side of two perforation sound absorption panels is provided with micropore acoustic board, between micropore acoustic board and perforation sound absorption panel, filling sucting sound material is made into absorbent treatment, between two micropore acoustic boards, be provided with dividing plate, between dividing plate, micropore acoustic board and anechoic sheet shell, form cavity, described cavity is only in communication with the outside by the hole on micropore acoustic board.
Described micropore acoustic board adopts particulate acoustic board, and described micropore acoustic board adopts particulate acoustic board, and described particulate acoustic board comprises cementing agent and particulate, and described particulate outside surface covers a layer binder, and the dihedral coefficient that covers the particulate after cementing agent is less than 1.3; Described particulate comprises skeleton particle and filler particles, and skeleton particle forms acoustic board skeleton, and the hole that filler particles enters between skeleton particle forms sound absorption gap.
The particulate that described particulate acoustic board adopts is 20～60 object drift-sands.
The particulate that described particulate acoustic board adopts is 40～60 object drift-sands.
The thickness of described particulate acoustic board is no more than 10mm.
The inside of described particulate acoustic board is provided with reinforcement.
Thickness H=40～the 100mm of described cavity.
The thickness of described acoustic absorbant is 50～100mm.
Described anechoic sheet shell is made up of perforation sound absorption panel, upper and lower cover plates and the two ends end socket of both sides.
Described dividing plate is arranged at the centre position between two micropore acoustic boards, and on dividing plate, is provided with gusset.
The beneficial effects of the utility model are: all have good sound absorbing capabilities in basic, normal, high frequency range, can keep the contour structures identical with conventional strip-type silencer, so that adopt original technique and production line to produce.
Brief description of the drawings
Fig. 1 is the structural representation of conventional strip-type silencer.
Fig. 2 is the front view of broad-band strip-type silencer of the present invention.
Fig. 3 is the left view of Fig. 2.
Fig. 4 is the vertical view of Fig. 2.
Fig. 5 is the micromechanism schematic diagram of the particulate acoustic board that adopts in Fig. 2.
Fig. 6 is another schematic diagram of the micromechanism of the particulate acoustic board that adopts in Fig. 2.
Fig. 7 is the absorption coefficient curve figure of embodiment 1 of the present utility model and the conventional strip-type silencer of same specification.
In figure, be labeled as: particulate 1, connection gap 2, semi-connected gap 3, perforation sound absorption panel 4, cavity 5, cover plate 6, end socket 7, reinforcement 8, dividing plate 9, particulate acoustic board 10, absorbent treatment 11, sound absorption packing material 12, supporting are followed closely 13, strengthened gusset 14, gusset 15.
Embodiment
Below in conjunction with drawings and Examples, the utility model is further illustrated.
Referring to Fig. 1, conventional strip-type silencer comprises the anechoic sheet shell being made up of perforation sound absorption panel 4, upper and lower cover plates 6 and the two ends end socket 7 of both sides, in anechoic sheet shell, be provided with and strengthen gusset 14 and sound absorption packing material 12, on perforation sound absorption panel 1, be connected with many supporting nails 13 on the thickness direction that is arranged in strip-type silencer, the length of supporting nail 13 and the thickness of strip-type silencer are suitable, and supporting nail 13 is arranged compartment of terrain on the plate face of perforation sound absorption panel 4.
As Fig. 2, Fig. 3, Fig. 4, shown in Fig. 5 and Fig. 6, broad-band strip-type silencer of the present utility model comprises anechoic sheet shell, anechoic sheet shell comprises the perforation sound absorption panel 4 of both sides, the inner side of two perforation sound absorption panels 4 is provided with micropore acoustic board, between micropore acoustic board and perforation sound absorption panel 4, filling sucting sound material is made into absorbent treatment 11, between two micropore acoustic boards, be provided with dividing plate 9, dividing plate 9, between micropore acoustic board and anechoic sheet shell, form cavity 5, described cavity 5 is only in communication with the outside by the hole on micropore acoustic board, cavity 5 is as back of the body chamber, built-in micropore acoustic board, dividing plate 9 forms micropore resonance sound-absorbing structure jointly with anechoic sheet shell, improve to a certain extent low frequency acoustic attenuation performance, simultaneously again with the fixing acoustic absorbant of micropore acoustic board, thereby can retain absorbent treatment 11, retain the good medium-high frequency acoustic attenuation performance of traditional chip dissipative muffler, obtain a kind of strip-type silencer of wideband.In other words, the low frequency characteristic of broad-band strip-type silencer is that the resonant cavity being formed by micropore acoustic board and cavity is contributed, and medium, high frequency characteristic is contributed by acoustic absorbant.
According to existing theory, the sound absorbing capabilities of micropore resonance sound-absorbing structure and percentage of perforation, back of the body chamber thickness, aperture, thickness of slab are relevant.Although low percentage of perforation is favourable to sound absorption peak value, sound sucting band is not wide, changes separately percentage of perforation and can not obtain high acoustical absorption coefficient and wide sound sucting band simultaneously.If back of the body chamber thickness reduces, the sound absorbing capabilities of low frequency declines, and the acoustical absorption coefficient of high frequency rises to some extent; If back of the body chamber thickness increases, the peak value of acoustical absorption coefficient will move to low frequency, and low frequency absorption performance is along with the increase of back of the body chamber thickness makes moderate progress.There is impact clearly in aperture on the maximal value of acoustical absorption coefficient, and acoustical absorption coefficient reduces and increases sharply with aperture, and the reducing of aperture also can be widened sound sucting band simultaneously, but the very little piercing aperture of processing can bring difficulty to processing technology, increases cost.The acoustical absorption coefficient of microperforated panel increases along with the increase of thickness of slab, and reason is also that short tube increases, and causes acoustic resistance to increase.Also find that thickness of slab increases, acoustical absorption coefficient peak value moves to low frequency direction simultaneously.Therefore, micropore resonance sound-absorbing structure is not also widely used.
The research recent according to inventor, described micropore acoustic board is except adopting microperforated panel, more recommend adoption particulate acoustic board 10, with regard to this kind of particulate acoustic board, applicant has submitted the patent application that application number is 2014103477351 " a kind of particulate acoustic board and preparation method thereof " on July 22nd, 2014 to China national Department of Intellectual Property, described particulate acoustic board 10 is mutually to link after wrapping up in a layer binder by the particulate 1 of different-diameter first again, the dihedral coefficient that covers the particulate 1 after cementing agent is less than 1.3, more connecing subglobular particulate profile is conducive to form particulate 1 described in gap between particulate and comprises the skeleton particle of greater particle size and the filler particles compared with small particle diameter, skeleton particle is mutually by knot, form acoustic board skeleton, filler particles is because particle diameter is little, can enter the gap between skeleton particle, and formation is less than the gap in described gap, described gap comprises the connection gap 2 that can communicate with adjacent slits and the semi-connected gap 3 that can not communicate with adjacent slits, be communicated with gap 2 and be equivalent to tortuous micropore, make particulate acoustic board 10 can form equally micropore resonance sound-absorbing structure, and due to the difference of mean particle dia, form big or small incomplete same connection gap 2, thereby all there is good effect of low-frequency sound absorption at wider sound sucting band, the existence in semi-connected gap 3 simultaneously makes particulate acoustic board 10 have certain defening effect concurrently, improve greatly low frequency acoustic attenuation performance.When wideband sound wave enters after broad-band strip-type silencer, when medium, high frequency sound wave enters absorbent treatment 11, cause the air vibration in gap.Due to the viscosity resistance of friction and air, make a part of acoustic energy be transformed into heat energy; In addition, the heat conduction between the air in hole and hole wall, fiber, also can cause thermal loss, makes sound energy attenuation.In the time that low-frequency sound wave enters particulate acoustic board 10, the particulate of different-diameter bears against mutually and the gap that forms is equivalent to the micropore of different-diameter one by one, forms a typical micropore resonant structure with cavity thereafter.The micropore of each different-diameter should have a resonance peak relatively, in the time that several different resonance peaks are superimposed, externally just presents the resonance peak that can cross over 100-800Hz frequency range.
Through actual monitoring, this broad-band strip-type silencer has improved nearly one times at the acoustical absorption coefficient of low-frequency range than traditional dissipative muffler, is also better than the acoustic attenuation performance of the micropore resonance sound-absorbing structure in the same thickness back of the body chamber of simple employing microperforated panel making.
Inventor further research also finds, selects suitable particulate form especially to select the particulate of suitable dihedral coefficient, and selects suitable particulate proportioning just can obtain the connection gaps 2 that are conducive to sound absorption more.For ensureing being uniformly distributed and the consistance of gap size of gap, the circularity of particulate is very important.If particulate is polygon, the gap between particulate will diminish.The gap that closely bears against formation with the object of various shapes is compared, and circular object bears against the gap of formation for maximum.Therefore, for obtaining better low frequency absorption performance, the particulate 1 that described particulate acoustic board adopts is 20～60 object drift-sands, and its acoustical absorption coefficient can all have more than 0.57 from 100-800Hz.
According to inventor's research, while making micropore resonance sound-absorbing structure with particulate acoustic board, the thickness of described particulate acoustic board is thicker within the specific limits, low frequency absorption performance is better, but after exceeding 10mm, performance improvement is not obvious, therefore advise that the thickness of particulate acoustic board is no more than 10mm, to alleviate the quality of whole sound suppressor, take into account sound absorbing capabilities and economy.
Because particulate acoustic board forms for boning, and thickness is not thick, and in order to gain in strength, the inside that is preferably in described particulate acoustic board is provided with reinforcement, conventional, reinforcement can be layer of metal grid or a slice highstrenghtpiston net etc.
According to inventor's research, the thickness of described cavity 5 advises at H=40～100mm, crosses thin low frequency absorption performance improvement not too obvious, although blocked up performance is better, and whole sound suppressor oversize.
According to inventor's research, the thickness of described acoustic absorbant is 50～100mm, crosses thin medium-high frequency sound absorbing capabilities good not, although blocked up performance is better, and whole sound suppressor oversize.
Suggestion acoustic absorbant adopts resistive acoustic absorbant, and recommend adoption unit weight is 4kg/m
3centrifugally glass-wool or 6～8kg/m
3melamine, to alleviate the quality of whole sound suppressor.
In addition, for ensureing the utility model broad-band strip-type silencer and the apparent consistance of existing strip-type silencer, so that adopt identical production line to complete making, described anechoic sheet shell is made up of perforation sound absorption panel 4, upper and lower cover plates 6 and the two ends end socket 7 of both sides.
embodiment 1:
Referring to Fig. 1, as shown in Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 6, broad-band strip-type silencer of the present utility model comprises anechoic sheet shell, perforation sound absorption panel 4, upper and lower cover plates 6 and two ends end socket 7 by both sides form, the inner side of two perforation sound absorption panels 4 is provided with the particulate acoustic board 10 of 10mm thickness, the particulate that particulate acoustic board 10 adopts is 40～60 object drift-sands, the acoustic absorbant of filling 50mm thickness between particulate acoustic board 10 and perforation sound absorption panel 4 is made into absorbent treatment 11, and it is 24kg/m that acoustic absorbant adopts unit weight
3super glass wool, between two particulate acoustic boards 10, be provided with dividing plate 9, between dividing plate 9, particulate acoustic board 10 and anechoic sheet shell, forming thickness is the cavity 5 of 40mm, described cavity 5 is only in communication with the outside by the open pore 2 on particulate acoustic board 10, cavity 5 is as back of the body chamber, and particulate acoustic board 10, dividing plate 9 form micropore resonance sound-absorbing structure jointly with anechoic sheet shell.
The conventional resistive plate silencer identical with physical dimension with above-mentioned broad-band strip-type silencer carries out Performance Ratio, and result is as shown in table 1 below:
Table 1 broad-band strip-type silencer and resistive plate silencer normal incidence sound absorption coefficient contrast table
| Frequency range (Hz) | 100 | 125 | 160 | 200 | 250 | 315 | 400 | 500 | 630 | 800 | 1000 | 1250 | 1600 | On average |
| A | 0.01 | 0.08 | 0.11 | 0.15 | 0.22 | 0.30 | 0.38 | 0.37 | 0.60 | 0.78 | 0.87 | 0.93 | 0.98 | 0.47 |
| B | 0.16 | 0.23 | 0.32 | 0.43 | 0.54 | 0.65 | 0.70 | 0.78 | 0.97 | 0.96 | 0.95 | 0.95 | 0.99 | 0.71 |
Note: A-resistive plate silencer, B-broad-band strip-type silencer.
embodiment 2:
Referring to Fig. 1, as shown in Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 6, broad-band strip-type silencer of the present utility model comprises anechoic sheet shell, perforation sound absorption panel 4, upper and lower cover plates 6 and two ends end socket 7 by both sides form, the inner side of two perforation sound absorption panels 4 is provided with the particulate acoustic board 10 of 30mm thickness, the particulate that particulate acoustic board 10 adopts is 40～60 object drift-sands, the acoustic absorbant of filling 50mm thickness between particulate acoustic board 10 and perforation sound absorption panel 4 is made into absorbent treatment 11, and it is 24kg/m that acoustic absorbant adopts unit weight
3super glass wool, between two particulate acoustic boards 10, be provided with dividing plate 9, between dividing plate 9, particulate acoustic board 10 and anechoic sheet shell, forming thickness is the cavity 5 of 20mm, described cavity 5 is only in communication with the outside by the open pore 2 on particulate acoustic board 10, cavity 5 is as back of the body chamber, and particulate acoustic board 10, dividing plate 9 form micropore resonance sound-absorbing structure jointly with anechoic sheet shell.Its performance is similar to embodiment 1, but cost is higher than embodiment 1.
Claims (9)
1. broad-band strip-type silencer, comprise anechoic sheet shell, anechoic sheet shell comprises the perforation sound absorption panel (4) of both sides, it is characterized in that: the inner side of two perforation sound absorption panels (4) is provided with micropore acoustic board, between micropore acoustic board and perforation sound absorption panel (4), filling sucting sound material is made into absorbent treatment (11), between two micropore acoustic boards, be provided with dividing plate (9), between dividing plate (9), micropore acoustic board and anechoic sheet shell, form cavity (5), described cavity (5) is only in communication with the outside by the hole on micropore acoustic board.
2. broad-band strip-type silencer as claimed in claim 1, it is characterized in that: described micropore acoustic board adopts particulate acoustic board (10), described particulate acoustic board (10) comprises cementing agent and particulate (1), described particulate (1) outside surface covers a layer binder, and the dihedral coefficient that covers the particulate (1) after cementing agent is less than 1.3; Described particulate (1) comprises skeleton particle and filler particles, and skeleton particle forms acoustic board skeleton, and the hole that filler particles enters between skeleton particle forms sound absorption gap.
3. broad-band strip-type silencer as claimed in claim 2, is characterized in that: the particulate (1) that described particulate acoustic board (10) adopts is 20～60 object drift-sands.
4. broad-band strip-type silencer as claimed in claim 2, is characterized in that: the particulate (1) that described particulate acoustic board (10) adopts is 40～60 object drift-sands.
5. broad-band strip-type silencer as claimed in claim 2, is characterized in that: the thickness of described particulate acoustic board (10) is no more than 10mm.
6. the broad-band strip-type silencer as described in claim 1,2,3,4 or 5, is characterized in that: the thickness H=40～100mm of described cavity (5).
7. the broad-band strip-type silencer as described in claim 1,2,3,4 or 5, is characterized in that: the thickness of described acoustic absorbant is 10～100mm.
8. the broad-band strip-type silencer as described in claim 1,2,3,4 or 5, is characterized in that: described anechoic sheet shell is made up of perforation sound absorption panel (4), upper and lower cover plates (6) and the two ends end socket (7) of both sides.
9. the broad-band strip-type silencer as described in claim 1,2,3,4 or 5, is characterized in that: described dividing plate (9) is arranged at the centre position between two micropore acoustic boards, and is provided with gusset on dividing plate (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420441019.5U CN204010667U (en) | 2014-08-07 | 2014-08-07 | Broad-band strip-type silencer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420441019.5U CN204010667U (en) | 2014-08-07 | 2014-08-07 | Broad-band strip-type silencer |
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| CN204010667U true CN204010667U (en) | 2014-12-10 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104167203A (en) * | 2014-08-07 | 2014-11-26 | 四川正升声学科技有限公司 | Broadband sheet type silencer |
| CN105986746A (en) * | 2015-03-03 | 2016-10-05 | 苏州静声泰环保科技有限公司 | Active and passive combined sound absorption door/window ventilation device |
| CN109487714A (en) * | 2018-09-28 | 2019-03-19 | 江苏新光环保工程有限公司 | A kind of full frequency band sqouynd absorption lowering noise plate and preparation method thereof |
| CN109605842A (en) * | 2018-10-25 | 2019-04-12 | 中国船舶重工集团公司第七〇九研究所 | A kind of broadband multilayer compound sound-absorption structural peculiar to vessel |
-
2014
- 2014-08-07 CN CN201420441019.5U patent/CN204010667U/en not_active Withdrawn - After Issue
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104167203A (en) * | 2014-08-07 | 2014-11-26 | 四川正升声学科技有限公司 | Broadband sheet type silencer |
| CN104167203B (en) * | 2014-08-07 | 2017-12-29 | 正升环境科技股份有限公司 | Broad-band strip-type silencer |
| CN105986746A (en) * | 2015-03-03 | 2016-10-05 | 苏州静声泰环保科技有限公司 | Active and passive combined sound absorption door/window ventilation device |
| CN109487714A (en) * | 2018-09-28 | 2019-03-19 | 江苏新光环保工程有限公司 | A kind of full frequency band sqouynd absorption lowering noise plate and preparation method thereof |
| CN109487714B (en) * | 2018-09-28 | 2021-04-30 | 江苏新光环保工程有限公司 | Full-band sound absorption and noise reduction plate and preparation method thereof |
| CN109605842A (en) * | 2018-10-25 | 2019-04-12 | 中国船舶重工集团公司第七〇九研究所 | A kind of broadband multilayer compound sound-absorption structural peculiar to vessel |
| CN109605842B (en) * | 2018-10-25 | 2022-10-21 | 中国船舶重工集团公司第七一九研究所 | Marine broadband multilayer composite sound absorption structure |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Wenjiang District 611130 of Sichuan city of Chengdu province Chengdu Strait science and Technology Industry Development Park Haike Road West No. 57 Patentee after: Positive ascension environment Polytron Technologies Inc Address before: 611130, No. 388, Taiwan Avenue, Wenjiang Strait science and Technology Park, Sichuan, Chengdu Patentee before: Sichuan Zhengsheng Acoustic Technology Co., Ltd. |
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| CP03 | Change of name, title or address | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20141210 Effective date of abandoning: 20171229 |
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| AV01 | Patent right actively abandoned |