CN108331789B - Damping-adjustable magnetorheological piezoelectric exhaust silencer - Google Patents

Damping-adjustable magnetorheological piezoelectric exhaust silencer Download PDF

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Publication number
CN108331789B
CN108331789B CN201810285376.XA CN201810285376A CN108331789B CN 108331789 B CN108331789 B CN 108331789B CN 201810285376 A CN201810285376 A CN 201810285376A CN 108331789 B CN108331789 B CN 108331789B
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cavity
cylinder
sound
rotating shaft
piezoelectric
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CN108331789A (en
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孟国连
王鸿云
毕成
朱俊华
赵爽
鄂世举
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Zhejiang Normal University CJNU
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00Details, component parts, or accessories
    • F04D29/66Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/661Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
    • F04D29/663Sound attenuation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D15/00Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
    • F01D15/12Combinations with mechanical gearing
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12Blades
    • F01D5/14Form or construction
    • F01D5/141Shape, i.e. outer, aerodynamic form
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12Blades
    • F01D5/14Form or construction
    • F01D5/147Construction, i.e. structural features, e.g. of weight-saving hollow blades
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B39/00Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
    • F04B39/0027Pulsation and noise damping means
    • F04B39/0083Pulsation and noise damping means using blow off silencers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B53/00Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/001Noise damping
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16FSPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32Details
    • F16F9/53Means for adjusting damping characteristics by varying fluid viscosity, e.g. electromagnetically
    • F16F9/535Magnetorheological [MR] fluid dampers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22STEAM GENERATION
    • F22BMETHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00Component parts or details of steam boilers
    • GPHYSICS
    • G10MUSICAL INSTRUMENTS; ACOUSTICS
    • G10KSOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/161Methods or devices for protecting against, or for damping, noise or other acoustic waves in general in systems with fluid flow
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02NELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
    • H02N2/00Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
    • H02N2/18Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators
    • H02N2/185Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators using fluid streams

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Electromagnetism (AREA)
  • Thermal Sciences (AREA)
  • Architecture (AREA)
  • Exhaust Silencers (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)

Abstract

The invention relates to the field of exhaust silencing equipment, in particular to a damping-adjustable magnetorheological piezoelectric exhaust silencer. Comprises a hollow cylinder body, and an air inlet pipe and an air outlet pipe are arranged along two ends of the cylinder body; the cylinder comprises a shell, glass wool and a perforated plate; the cylinder is divided into a first cavity, a second cavity and a third cavity by a left partition plate and a right partition plate along the direction vertical to the axis of the cylinder, the air inlet pipe is communicated with the first cavity, and the air outlet pipe is communicated with the third cavity; the left partition plate is provided with a rotating shaft coaxial with the cylinder, the rotating shaft extending into the first cavity is provided with a sound-absorbing blade, the sound-absorbing blade is formed by bonding a piezoelectric wafer and a metal substrate, and the rotating shaft extending into the second cavity is provided with a damping unit. Advantages and features: the sound absorption blades are utilized to convert the kinetic energy of the airflow into mechanical energy, and the sound absorption capacity is strong; the damping unit is self-powered by electric energy generated by the piezoelectric effect, the structure is simple, and the cost is reduced.

Description

Damping-adjustable magnetorheological piezoelectric exhaust silencer
Technical Field
The invention relates to the field of exhaust silencing equipment, in particular to a damping-adjustable magnetorheological piezoelectric exhaust silencer.
Background
An exhaust muffler is a device that prevents sound from propagating while allowing airflow to pass through, and is an important measure for eliminating aerodynamic noise. An exhaust muffler is a noise reduction device installed in an exhaust system of an aerodynamic device (e.g., a blower, an air compressor, a boiler exhaust port, a generator, a water pump, etc., which has relatively loud noise at an exhaust port). The exhaust silencer has many kinds, is developed according to the anti-noise, spray-noise-resistance composite silencing principle, and mainly has small-hole spraying, capacity-expanding and sound-absorbing functions.
Among the prior art, exhaust muffler's exhaust silencing effect is not ideal enough, and the reason lies in: 1. the silencing method based on the small hole injection has the advantages that each hole has own natural frequency, and only sound waves with certain frequencies near the natural frequency of the mesh can pass through the mesh, so that the sound absorption coefficient is low, the absorption frequency band is narrow, and the sound absorption is difficult to control; 2. the sound absorption method based on impedance matching has a good effect on low frequencies and a poor effect on high frequencies.
Disclosure of Invention
Aiming at the problems in the silencing aspect of the existing exhaust silencer, the invention provides a damping-adjustable magneto-rheological piezoelectric exhaust silencer, which adopts the following implementation scheme: the air outlet pipe is arranged along the axis of the other end of the cylinder, and the left end of the air outlet pipe is conical; the cylinder comprises a shell, glass wool and a perforated plate, and a plurality of air holes are formed in the perforated plate; the cylinder is divided into a first cavity, a second cavity and a third cavity by a left partition plate and a right partition plate along the direction vertical to the axis of the cylinder, the air inlet pipe is communicated with the first cavity, and the air outlet pipe is communicated with the third cavity; the left clapboard and the right clapboard are uniformly provided with a left circulation hole and a right circulation hole, the sum of the sectional areas of the left circulation hole is larger than or equal to the sum of the sectional areas of the air inlet pipe, and the sum of the sectional areas of the right circulation hole is larger than or equal to the sum of the sectional areas of the left circulation hole; the left partition plate is provided with a rotating shaft coaxial with the cylinder, the end surface of a shaft platform of the rotating shaft extending into the first cavity is uniformly provided with sound-absorbing blades through screws, and the rotating shaft extending into the second cavity is provided with a damping unit; the sound-absorbing blade is formed by bonding a piezoelectric wafer and a metal substrate; the damping unit comprises a cylindrical hollow round cup coaxial with the cylinder, an annular end cover and magnetorheological fluid, the end cover is installed at the left end part of the round cup through a screw and fixed on the left partition plate through the screw, and a cylindrical cavity is formed inside the round cup and the end cover; the inner wall of the round cup is uniformly and fixedly provided with annular outer discs, the rotating shaft is sleeved with inner discs uniformly separated by sleeves, the outer discs and the inner discs are arranged in a staggered mode, coils are sleeved on the outer edges of the inner discs, gaps formed among the round cup, the end covers, the outer discs, the inner discs, the coils and the sleeves are filled with magnetorheological fluid, sealing is carried out through sealing rings, and bearings are arranged between the rotating shaft and the end covers.
In the invention, in order to improve the sound absorption and noise reduction capability of the sound absorption blade, the sound absorption blade E is sleeved on a thin shaft t1 of a rotating shaft t, is connected with the end surface of a shaft stand t2 through a screw, and forms a certain inclination angle beta (similar to the inclination angle of a blade of an electric fan) with the axial direction, the inclination angle of the sound absorption blade is 110 degrees, the sound absorption blade is of a curved rainbow-type structure, the curvature radius of a piezoelectric wafer is smaller than that of a metal substrate, the thickness of the piezoelectric wafer is 0.15-0.3 mm PZT4, the metal substrate is beryllium bronze, and the thickness ratio of the metal substrate to the piezoelectric wafer is 1-2.5, so that the sound absorption and noise reduction capability of the.
After the airflow enters the first cavity through the air inlet pipe, the airflow generates aerodynamic force to drive the rotating shaft to rotate when blowing to the sound-absorbing blades, and the rotating shaft rotates to drive the inner disc to synchronously rotate; meanwhile, the vibration of the sound wave causes the piezoelectric effect of the piezoelectric wafer, the piezoelectric wafer is stressed to generate electric charge, the electric charge is stored through a storage circuit and then is applied to a coil of the damping unit; according to the positive piezoelectric effect of the piezoelectric wafer, the amount of charge generated by the piezoelectric wafer under pressure is proportional to the magnitude of the pressure, so that the magnitude of the current applied to the coil of the damping unit is controlled by the value of the charge generated by the piezoelectric wafer. The change of the current in the coil can cause the change of the magnetic field, and the change of the magnetic field causes the change of the mechanical property of the magnetorheological fluid, thereby causing the damping force of the inner disc of the damping unit to be changed, and realizing the intelligent control of the external noise.
The air flow in the silencer is generally fast in flow speed and high in noise of the air flow, the sound power of various frequency bands in the noise is reduced after the kinetic energy of the air flow is converted into mechanical energy through the sound-absorbing blades, so that the noise is greatly weakened, meanwhile, the sound energy is converted into electric energy through the piezoelectric effect of the piezoelectric wafer, low-frequency sound waves can be actively absorbed, then the medium-high frequency sound waves can be passively absorbed through the combined action of the perforated plate and the glass wool, and the residual noise is effectively absorbed.
Advantages and features: 1) the sound absorption blades are utilized to convert the kinetic energy of the airflow into mechanical energy, the sound power of various frequency bands is reduced, the noise is weakened, the sound absorption capacity is strong, and the reliability is high; 2) the damping unit is self-powered by electric energy generated by the piezoelectric effect, the structure is simple, and the cost is reduced; 3) the low frequency sound waves are actively absorbed by the piezoelectric effect.
Drawings
FIG. 1 is a schematic diagram of a magnetorheological piezoelectric exhaust muffler with adjustable damping according to a preferred embodiment of the present invention;
FIG. 2 is a schematic view of an assembly structure of a sound-absorbing blade and a rotating shaft according to a preferred embodiment of the present invention;
Detailed Description
A damping-adjustable magneto-rheological piezoelectric exhaust silencer comprises a hollow cylinder V, wherein an air inlet pipe a is arranged at a position deviating from the axis of one end of the cylinder V, and an air outlet pipe p with a conical p1 left end is arranged at a position along the axis of the other end of the cylinder V; the cylinder V comprises a shell b, glass wool c and a perforated plate d, and a plurality of air holes d1 are formed in the perforated plate d; the cylinder V is divided into a first cavity A, a second cavity B and a third cavity C by a left partition plate g and a right partition plate m along the direction vertical to the axis of the cylinder V, an air inlet pipe a is communicated with the first cavity A, and an air outlet pipe p is communicated with the third cavity C; the left partition plate g and the right partition plate m are uniformly provided with a left circulation hole g1 and a right circulation hole m1, the sum of the sectional areas of the left circulation hole g1 is larger than or equal to the sum of the sectional areas of the air inlet pipe a, and the sum of the sectional areas of the right circulation hole m1 is larger than or equal to the sum of the sectional areas of the left circulation hole g 1; the left partition plate g is provided with a rotating shaft t coaxial with the cylinder V, sound-absorbing blades E are uniformly arranged on the end face of a boss t2 of the rotating shaft t extending into the first cavity A through screws, and damping units Y are arranged on the rotating shaft t extending into the second cavity B; the sound-absorbing blade E is formed by bonding a piezoelectric wafer E1 and a metal substrate E2; the damping unit Y comprises a cylindrical hollow round cup j coaxial with the cylinder V, an annular end cover i and magnetorheological fluid r, the end cover i is installed at the left end of the round cup j through a screw and fixed on the left partition plate through the screw, and a cylindrical cavity is formed inside the round cup j and the end cover i; the inner wall of the round cup j is uniformly and fixedly provided with annular outer discs s, the rotating shaft t is sleeved with annular inner discs q which are uniformly separated by sleeves n, the outer discs s and the inner discs q are arranged in a staggered mode, coils k are sleeved on the outer edges of the inner discs q, gaps U formed among the round cup j, the end cover i, the outer discs s, the inner discs q, the coils k and the sleeves n are filled with magnetorheological fluid r, sealing is carried out through sealing rings h, and a bearing f is arranged between the rotating shaft t and the end cover i.
In the invention, in order to improve the sound absorption and noise reduction capability of the sound absorption blade E, the sound absorption blade E is sleeved on a thin shaft t1 of a rotating shaft t, is connected with the end face of a shaft stand t2 through a screw, and forms a certain inclination angle beta (similar to the inclination angle of a blade of an electric fan) with the axial direction, the inclination angle beta of the sound absorption blade E is 110 degrees, the sound absorption blade E is of a curved rainbow type structure, the curvature radius of a piezoelectric wafer E1 is smaller than that of a metal substrate E2, the thickness of the piezoelectric wafer E1 is PZT4 of 0.15-0.3 mm, the metal substrate E2 is beryllium copper, and the ratio of the thicknesses of the metal substrate E2 and the piezoelectric wafer E1 is 1-2.5, so that the sound absorption and noise reduction capability.
After the airflow enters the first cavity A through the air inlet pipe a, the airflow generates aerodynamic force to drive the rotating shaft t to rotate when blowing to the sound-absorbing blades E, and the rotating shaft t rotates to drive the inner disc q to synchronously rotate; meanwhile, the vibration of the sound wave causes the piezoelectric effect of the piezoelectric wafer e1, the piezoelectric wafer e1 is stressed to generate electric charge, the electric charge is stored through a storage circuit and then is applied to a coil k of the damping unit Y; from the positive piezoelectric effect of the piezoelectric wafer e1, the amount of charge generated by the piezoelectric wafer e1 under pressure is proportional to the magnitude of the pressure, so that the magnitude of the current applied to the coil k of the damping unit Y is controlled by the value of the charge generated by the piezoelectric wafer e1, and when the airflow noise vibration force is large, the amount of charge generated by the piezoelectric wafer e1 is large, so that the current applied to the coil k of the damping unit Y is large. The change of the current in the coil k can cause the change of the magnitude of the magnetic field, and the change of the magnetic field causes the change of the mechanical property of the magnetorheological fluid r, so that the damping force of the disc q in the damping unit Y is also changed, and the intelligent control of the external noise is realized.
The air flow in the silencer is generally fast in flow speed and high in noise of the air flow, after the kinetic energy of the air flow is converted into mechanical energy through the sound-absorbing blades E, the sound power of various frequency bands in the noise is reduced, so that the noise is greatly weakened, meanwhile, the sound energy is converted into electric energy through the piezoelectric effect of the piezoelectric wafer E1, low-frequency sound waves can be actively absorbed, then the middle-high frequency sound waves can be passively absorbed through the combined action of the perforated plate d and the glass wool c, and the residual noise is effectively absorbed.
The above description is only an embodiment of the present invention, but the technical features of the present invention are not limited thereto, and any changes or modifications within the technical field of the present invention by those skilled in the art are covered by the claims of the present invention.

Claims (1)

1. The damping-adjustable magnetorheological piezoelectric exhaust silencer is characterized in that: the air outlet pipe is arranged along the axis of the other end of the cylinder, and the left end of the air outlet pipe is conical; the cylinder comprises a shell, glass wool and a perforated plate, and a plurality of air holes are formed in the perforated plate; the cylinder is divided into a first cavity, a second cavity and a third cavity by a left partition plate and a right partition plate along the direction vertical to the axis of the cylinder, the air inlet pipe is communicated with the first cavity, and the air outlet pipe is communicated with the third cavity; the left clapboard and the right clapboard are uniformly provided with a left circulation hole and a right circulation hole, the sum of the sectional areas of the left circulation hole is larger than or equal to the sum of the sectional areas of the air inlet pipe, and the sum of the sectional areas of the right circulation hole is larger than or equal to the sum of the sectional areas of the left circulation hole; the left partition plate is provided with a rotating shaft coaxial with the cylinder, the end surface of a shaft platform of the rotating shaft extending into the first cavity is uniformly provided with sound-absorbing blades through screws, and the rotating shaft extending into the second cavity is provided with a damping unit; the sound-absorbing blade is formed by bonding a piezoelectric wafer and a metal substrate; the damping unit comprises a cylindrical hollow round cup coaxial with the cylinder, an annular end cover and magnetorheological fluid, the end cover is installed at the left end part of the round cup through a screw and fixed on the left partition plate through the screw, and a cylindrical cavity is formed inside the round cup and the end cover; the inner wall of the round cup is uniformly and fixedly provided with annular outer discs, the rotating shaft is sleeved with inner discs uniformly separated by sleeves, the outer discs and the inner discs are arranged in a staggered manner, the outer edge of each inner disc is sleeved with a coil, gaps formed among the round cup, the end cover, the outer discs, the inner discs, the coils and the sleeves are filled with magnetorheological fluid and are sealed by sealing rings, and a bearing is arranged between the rotating shaft and the end cover; the sound-absorbing blade is sleeved on the thin shaft of the rotating shaft, is connected with the end face of the shaft base through a screw, and forms a certain inclination angle beta with the axial direction, the inclination angle beta of the sound-absorbing blade is 110 degrees, the sound-absorbing blade is of a curved rainbow type structure, the curvature radius of the piezoelectric wafer is smaller than that of the metal substrate, the thickness of the piezoelectric wafer is 0.15-0.3 mm of PZT4, the metal substrate is beryllium bronze, and the thickness ratio of the metal substrate to the piezoelectric wafer is 1-2.5.
CN201810285376.XA 2018-03-19 2018-03-19 Damping-adjustable magnetorheological piezoelectric exhaust silencer Active CN108331789B (en)

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Publication number Priority date Publication date Assignee Title
CN111188423A (en) * 2020-03-13 2020-05-22 邵斌 Building partition plate with noise reduction function for house removal
CN114613346A (en) * 2020-12-08 2022-06-10 香港大学浙江科学技术研究院 Tunable sound insulation device and method for controlling sound insulation

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN87205551U (en) * 1987-03-24 1988-01-27 昆明大滇实业公司金属推拉窗门厂 Multi-effect all frequency spring push-pull combined muffler
CN1482376A (en) * 2003-07-24 2004-03-17 上海交通大学 Construction variable rotary magnetic current flowing deforming brake
CN2659492Y (en) * 2003-12-05 2004-12-01 中国科学技术大学 Combined magnetic rheopetic rotary damper
CN1900555A (en) * 2005-07-20 2007-01-24 上海工程技术大学 Rotary type magnetic flow change torque changer
CN202789016U (en) * 2012-07-13 2013-03-13 成都进界科技有限公司 Engine exhaust silencer
CN206769998U (en) * 2017-05-12 2017-12-19 广州卡迅能源科技有限公司 A kind of muffler of generating set

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09184497A (en) * 1995-12-28 1997-07-15 Daikin Ind Ltd Fan noise reducing device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN87205551U (en) * 1987-03-24 1988-01-27 昆明大滇实业公司金属推拉窗门厂 Multi-effect all frequency spring push-pull combined muffler
CN1482376A (en) * 2003-07-24 2004-03-17 上海交通大学 Construction variable rotary magnetic current flowing deforming brake
CN2659492Y (en) * 2003-12-05 2004-12-01 中国科学技术大学 Combined magnetic rheopetic rotary damper
CN1900555A (en) * 2005-07-20 2007-01-24 上海工程技术大学 Rotary type magnetic flow change torque changer
CN202789016U (en) * 2012-07-13 2013-03-13 成都进界科技有限公司 Engine exhaust silencer
CN206769998U (en) * 2017-05-12 2017-12-19 广州卡迅能源科技有限公司 A kind of muffler of generating set

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