CN101871473B

CN101871473B - Impedance composite muffler

Info

Publication number: CN101871473B
Application number: CN201010202269XA
Authority: CN
Inventors: 杨春敏; 张景松; 高云鹏
Original assignee: China University of Mining and Technology Beijing CUMTB
Current assignee: China University of Mining and Technology Beijing CUMTB
Priority date: 2010-06-09
Filing date: 2010-06-09
Publication date: 2012-03-07
Anticipated expiration: 2030-06-09
Also published as: CN101871473A

Abstract

The utility model relates to an impedance compound muffler, which is especially suitable for noise reduction of an air motor in an underground air fan in a coal mine. It includes a muffler tube, a rear cover, and an annular baffle. The inner orifice tube and the outer orifice tube are arranged on the left side of the annular baffle. The inner orifice tube and the outer orifice tube are respectively filled with sound-absorbing materials. The left end of the plate tube is provided with a left annular baffle; the middle hole of the annular rear cover is provided with an outlet pipe section, and a through hole ③ is opened on the pipe wall of the outlet pipe section; A number of flow holes ④; the inner cavity at the right end of the inner orifice tube is provided with a right circular baffle, the right circular baffle is provided with an orifice sleeve and an inner pipe section, and the right side of the annular baffle is provided with an orifice sleeve The concave ring space body surrounded by the tube and the inner ring baffle is filled with sound-absorbing materials; the right end of the muffler is provided with a ring-shaped front cover or a ring-shaped flange, and the middle part of the ring-shaped front cover is provided with an inlet pipe section , There is a right circular baffle at the entrance of the inlet pipe section. The utility model has the advantages of simple structure and good sound elimination and noise reduction effects.

Description

A kind of impedance composite muffler

Technical field

The present invention relates to impedance composite muffler, be particularly useful under the comparatively narrow and small coal mine of working space the noise reduction of gas motor in the pneumatic blower fan and pneumatic equipment.

Background technique

The characteristics of coal mine operation environment are that it exists flammable explosive gas (like CH ₄, CO, H ₂Deng), potential explosion risk factor such as coal dust.And according to incompletely statistics, the exogenous mine fire accident in about 30% the coal mine gas dust explosion accident, more than 70% is prolonged combustion by electrical equipment spark, machinery spark or non-metallic material and is caused.Therefore if can underground coal mine electrical equipment be changed by fluid power or strength driving, will eliminate potential safety hazard very big in the Coal Production.At present in the coal mining of China, advantage such as pneumatic motor is big with its per unit volume output power, and usability is safe and reliable and being used widely.But the shortcoming of a maximum of pneumatic motor is exactly that noise is big, and under situation about not fixing a silencer, the pneumatic motor noise can be up to 120dB, and its noise pollution is very serious.Especially on the narrow and small relatively working surface in down-hole, this noise is insupportable especially.So no matter say from the safety meaning or from the meaning of boosting productivity, it is very to be badly in need of in the Coal Production that pneumatic motor is carried out effective noise reduction process.

The noise of pneumatic motor mainly is made up of exhaust sound and mechanical noise.See that from noise frequency exhaust sound spreads all over the whole frequency band of pneumatic motor noise, mechanical noise then is embodied on some crest frequency.

Dissipative muffler mainly utilizes sound-absorbing material to come mute.When sound wave entering dissipative muffler, a part of acoustic energy is just absorbed by sound-absorbing material, plays the noise elimination effect.Dissipative muffler can be eliminated the noise in the middle and high frequency scope of broad, particularly ear-piercing high frequency sound wave is had outstanding noise elimination effect, but to low-frequency noise noise elimination weak effect.

Reactive muffler is called acoustic filter again; It is an appropriate combination of utilizing the pipeline or the so-called resonant cavity of different shape, size; Impedance mismatching when causing sound wave in system, to propagate makes sound wave that reflection or interference take place in pipeline and resonant cavity, thereby reduces the acoustic energy of output.It is processed according to the acoustics filtering principle, like resonance exhaust silencer, expanssion type silencing apparatus and interference silencing apparatus etc.Reactive muffler has good low frequency acoustic attenuation performance, and simple structure but noise elimination frequency band is narrow is relatively poor relatively to high frequency noise elimination effect.

Therefore for pneumatic motor, use resistance noise reduction or reactive muffling technology all to be difficult to noise is reached desirable noise elimination effect on whole frequency band merely.

Summary of the invention

Technical problem: the objective of the invention is provides a kind of simple in structure to the problem that exists in the prior art, the impedance composite muffler of noise elimination, excellent noise reduction effect.

Technological scheme: impedance composite muffler of the present invention; Comprise silencing pot; Be located at the annular back shroud or the dish type back shroud of silencing pot left end; Be provided with ring baffle in the silencing pot, be provided with interior orifice pipe and outer orifice pipe that fit forms the annular pass in the ring baffle left side, be filled with sound-absorbing material respectively in the interior orifice pipe and in the interlayer of outer orifice pipe and silencing pot inwall; The left end of outer orifice pipe is provided with the left ring baffle that forms resonant cavity with annular back shroud, and 2. left ring baffle is provided with the ring baffle hole that communicates with the annular pass; Be provided with the inner in the mesopore of said annular back shroud and be fixed with the circular baffle plate outlet pipe section; Have on the tube wall of outlet pipe section with the ring baffle hole 2., the through hole that is connected of interior orifice plate pipe tap 3., have several through flow holes 4. on the inboard noise elimination barrel of said dish type back shroud; Be provided with right circular baffle plate in the interior orifice pipe right-hand member inner chamber, right circular baffle plate is provided with the orifice plate sleeve pipe that passes the ring baffle endoporus, is set with interior pipeline section in the orifice plate sleeve pipe, has the through hole that the annular pass is connected on the tube wall of orifice plate sleeve pipe; The ring baffle right side is provided with the scrobicular ring space body that is surrounded by orifice plate sleeve pipe and interior ring baffle, is filled with sound-absorbing material in the scrobicular ring space body; The outer cover of interior pipeline section is equipped with the outer segment that has some through-flow apertures on its tube wall; Described silencing pot right-hand member is provided with annular front shroud or annular flange dish, and the middle part of said annular front shroud is provided with the import pipeline section, and import pipeline section ingress is provided with the right circular baffle plate that is fixed on the outer segment right-hand member.

Described silencing pot be single cylindrical shell or about two cylindrical shells be formed by connecting; The described through hole that is connected with the annular pass is some through-flow apertures.

Technique effect: the present invention is through carrying out suitably reasonably combination to difform pipeline and resonant cavity; And at the non-overcurrent space filling sound-absorbing material of silencing apparatus; Reactive muffling is combined with the resistance noise reduction technology; Be formed with the mazy type resonant cavity of resistance filtering, cause that interstitial air moves back and forth, make this impedance composite muffler have the advantage of dissipative muffler and reactive muffler concurrently thereby let sound wave in the interfibrous space of sound-absorbing material, propagate; Well pneumatic equipment running middle outlet air-flow is carried out noise reduction process, eliminate the noise pollution of operational site.Because the air of fiber surface receives the influence of hole wall to be difficult for motion; So near the air movement speed faster or slower the fiber because the viscosity of air has produced corresponding retardance resistance, makes the kinetic energy of sound wave constantly be converted into heat energy; Thereby make SATT, reach the purpose of resistance noise reduction.This silencing apparatus has the advantage of dissipative muffler and reactive muffler concurrently, its compact structure, and compact size, excellent noise reduction effect has practicability widely.

Description of drawings

Fig. 1 is instance one structural representation of the present invention.

Fig. 2 is instance two structural representations of the present invention.

Fig. 3 is instance three structural representations of the present invention.

Among the figure: silencing pot-1, internal channel-2, annular back shroud-3, sound-absorbing material-4, import pipeline section-5, right circular baffle plate-6; Sleeve pipe-7, outer segment-8, interior pipeline section-9, orifice plate sleeve pipe-10, ring baffle-11; Outer orifice pipe-12, interior orifice pipe-13, right circular baffle plate-14, left ring baffle-15, outlet pipe section-16; Left side circular baffle plate-17, interior ring baffle-18, annular front shroud-19, flange plate-20, dish type back shroud-21.

Embodiment

To combine 1 pair of one embodiment of the present of invention of accompanying drawing to do further to describe below:

Shown in Figure 1, impedance composite muffler mainly is made up of silencing pot 1, internal channel 2, back shroud 3 and sound-absorbing material 4 etc.The right-hand member of silencing pot 1 is welded with annular front shroud 19, and left end is welded with annular back shroud 3, is welded with ring baffle 11 in the silencing pot 1, is welded with import pipeline section 5 on the annular front shroud 19; Ring baffle 11 left sides are provided with the interior orifice pipe 13 and outer orifice pipe 12 that fit forms annular pass D, are filled with sound-absorbing material 4 respectively in interior orifice pipe 13 and silencing pot 1 inwall, the outer orifice pipe 12, and sound-absorbing material 4 is flame-retardant materials such as glass wool or metal foam; The left end of outer orifice pipe 12 is welded with the left ring baffle 15 that forms resonant cavity V and annular pass E with

annular back shroud

3, and 2. left ring baffle 15 is provided with the some through-flow aperture that communicates with annular pass D; Be provided with left circular baffle plate 17 in the interior orifice pipe 13 left end inner chambers; Left side circular baffle plate 17 is provided with and has through-flow aperture outlet pipe section 16 3. on the tube wall; Be provided with right circular baffle plate 14 in the interior orifice pipe 13 right-hand member inner chambers; Right circular baffle plate 14 is provided with the orifice plate sleeve pipe 10 that passes ring baffle 11 endoporus, pipeline section 9 in being set with in the orifice plate sleeve pipe 10; Ring baffle 11 right sides are provided with the scrobicular ring space body that is surrounded by orifice plate sleeve pipe 7 and interior ring baffle 18, are filled with sound-absorbing material 4 in the scrobicular ring space body; The outer cover of interior pipeline section 9 is equipped with the outer segment 8 that its tube wall middle part has some through-flow apertures, and the right-hand member of outer segment 8 is provided with right circular baffle plate 6.After the left end annular space of silencing pot 1 is filled with sound-absorbing material 4, annular space has been wrapped up the internal channel 2 of sound-absorbing material 4 and packed into, pushed up orifice pipe 10 when right circular baffle plate 14 and promptly represent to be in place by the left end of silencing pot 1.With the full sound-absorbing material 4 of interior orifice pipe 13 inner fillings, then back shroud 3 is packed into by the left end of silencing pot 1, promptly represent to be in place when pushing up interior orifice pipe 13.Be that mounting process is convenient, silencing pot 1 can be a single cylindrical shell, also can be from ring baffle 11 boundary about two cylindrical shells, connect as one through flange.At last back shroud 3 is welded on the silencing pot 1.When air-flow gets into this silencing apparatus 1 via import pipeline section 15, through after the of short duration expansion, owing to stopping of right circular baffle plate 6; After throttling, get into annular pass A; Go into annular pass B through 1. orifice flow then, through getting into cylindrical channel C after the of short duration expansion, then via orifice pipe 10, orifice pipe 13 entering annular pass D; Get into annular pass E via 2. hole again and further expand, and then 3. get into outlet pipe section 16 via through-flow aperture and be discharged to atmosphere.Formed I, II, III, IV and many resonant cavities of V thus, made sound wave produce reflection or interference phenomenon, thereby significantly reduce air-flow, reached the purpose of attenuate acoustic noise to extraradial acoustic energy.

Shown in Figure 2, basic identical with embodiment one, exist together mutually slightly.Difference: silencing pot 1 right-hand member is a flange plate 20; Removed right circular baffle plate 6, flange plate 20 is an annular, is with several screw holes outward, and the through hole at middle part directly communicates with the hole of passing through of interior pipeline section 9 and outer segment 8.

Shown in Figure 3, basic identical with embodiment one, exist together mutually slightly.Difference: silencing pot 1 right-hand member is a flange plate 20; Removed right circular baffle plate 6, flange plate 20 is an annular, is with several screw holes outward, and the through hole at middle part directly communicates with the hole of passing through of interior pipeline section 9 and outer segment 8; Silencing pot 1 left end is the dish type back shroud 21 of atresia; Have several through flow holes of being connected with annular pass D on the barrel at silencing pot 1 rear portion 4..

Claims

1. A kind of impedance compound muffler, its characteristic is: it comprises muffler cylinder (1), is located at the annular rear cover plate (3) of muffler cylinder (1) left end, is provided with annular in muffler cylinder (1). The baffle plate (11), the inner orifice plate tube (13) and the outer orifice plate tube (12) which are sleeved to form the annular channel (D) are arranged in the left side of the annular baffle plate (11), and the inner orifice plate tube (13) And the interlayer between the outer orifice tube (12) and the inner wall of the muffler tube (1) is filled with sound-absorbing material (4), and the left end of the outer orifice tube (12) is provided with an annular back cover (3) to form a resonance The left annular baffle (15) of the cavity (V), the left annular baffle (15) is provided with the annular baffle hole communicating with the annular passage (D); There is an outlet pipe section (16) with a circular baffle (17) fixed at the inner end, and the pipe wall of the outlet pipe section (16) is provided with a through hole communicating with the annular baffle hole and the pipe wall hole (E) of the inner orifice plate , the first right circular baffle (14) is provided in the inner cavity of the right end of the inner orifice tube (13), and the first right circular baffle (14) is provided with an inner hole passing through the inner hole of the annular baffle (11). The orifice casing (10), the inner orifice casing (10) is set with the inner pipe section (9), and the wall of the inner orifice casing (10) is provided with a through hole communicating with the annular channel (D) , the right side of the annular baffle (11) is provided with a concave ring space surrounded by the outer orifice sleeve (7) and the inner annular baffle (18), and the concave ring space is filled with sound-absorbing materials (4); The outer part of the pipe section (9) is equipped with an outer pipe section (8) with several small holes for flow on the pipe wall; the right end of the muffler (1) is provided with an annular front cover (19), and the annular front The middle part of the cover plate (19) is provided with an inlet pipe section (5), and the entrance of the inlet pipe section (5) is provided with a second right circular baffle plate (6) fixed on the right end of the outer pipe section (8).

2. A compound impedance muffler, its characteristic is: it comprises muffler cylinder (1), is located at the annular rear cover plate (3) of muffler cylinder (1) left end, is provided with annular in muffler cylinder (1). The baffle plate (11), the inner orifice plate tube (13) and the outer orifice plate tube (12) which are sleeved to form the annular channel (D) are arranged in the left side of the annular baffle plate (11), and the inner orifice plate tube (13) And the interlayer between the outer orifice tube (12) and the inner wall of the muffler tube (1) is filled with sound-absorbing material (4), and the left end of the outer orifice tube (12) is provided with an annular back cover (3) to form a resonance The left annular baffle (15) of the cavity (V), the left annular baffle (15) is provided with the annular baffle hole communicating with the annular passage (D); There is an outlet pipe section (16) with a circular baffle (17) fixed at the inner end, and the pipe wall of the outlet pipe section (16) is provided with a through hole communicating with the annular baffle hole and the pipe wall hole (E) of the inner orifice plate , the first right circular baffle (14) is provided in the inner cavity of the right end of the inner orifice tube (13), and the first right circular baffle (14) is provided with an inner hole passing through the inner hole of the annular baffle (11) Orifice plate casing (10), the inner pipe section (9) is set inside the inner orifice plate casing (10), and a through hole communicating with the annular channel (D) is opened on the pipe wall of the inner orifice plate casing (10) , the right side of the annular baffle (11) is provided with a concave ring space surrounded by the outer orifice sleeve (7) and the inner annular baffle (18), and the concave ring space is filled with sound-absorbing materials (4); The outer casing of the pipe section (9) is provided with an outer pipe section (8) with several small holes for flow on the pipe wall; the right end of the muffler (1) is provided with an annular flange (20).

3. A kind of impedance composite type muffler, its characteristic is: it comprises muffler tube (1), is located at the disc-shaped rear cover plate (21) of muffler tube (1) left end, the inner side of disc-shaped rear cover plate (21) There are several flow holes on the wall of the muffler (1); the muffler (1) is provided with a ring-shaped baffle (11), and the left side of the ring-shaped baffle (11) is provided with a sleeve to form an annular passage ( D) the inner orifice tube (13) and the outer orifice tube (12), the inner orifice tube (13) and the interlayer of the outer orifice tube (12) and the inner wall of the muffler tube (1) are respectively filled with suction Acoustic material (4), the left end of the outer orifice tube (12) is provided with a left annular baffle (15) forming a resonant cavity (V) with the disc-shaped back cover (21), and the inner orifice tube (13) is inside the right end. The cavity is provided with a first right circular baffle (14), and the first right circular baffle (14) is provided with an inner orifice plate casing (10) passing through the inner hole of the annular baffle (11), and the inner hole The inner tube section (9) is set inside the plate casing (10), and the tube wall of the inner orifice plate casing (10) is provided with a through hole communicating with the annular passage (D), and the right side of the annular baffle (11) is provided There is a concave ring space surrounded by the outer orifice sleeve (7) and the inner annular baffle (18), and the concave ring space is filled with sound-absorbing material (4); The outer pipe section (8) with several small flow holes is opened on the wall; the right end of the muffler (1) is provided with an annular flange (20).

4. The impedance compound muffler according to claim 1, 2 or 3, characterized in that: the muffler cylinder (1) is a single cylinder or two left and right cylinders connected.

5. The impedance composite muffler according to claim 1, 2 or 3, characterized in that: said through-holes communicating with the annular channel (D) are several through-holes.