212 results about "Resonance chamber" patented technology

Various embodiments of an ear-wearable electronic device are disclosed. The device includes a housing having a top shell and a bottom shell, a microphone disposed within the housing, and an acoustic path disposed at least partially within the housing and extending between an acoustic port disposed at an outer surface of the housing and an outlet disposed within the housing that acoustically couples the acoustic path to an inlet of the microphone. The device further includes an acoustic filter disposed at least partially within an inner surface of the top shell and includes a neck and a resonance cavity acoustically coupled to the neck. The acoustic filter is acoustically coupled to the acoustic path via the neck. Further, the acoustic filter is configured to reduce an intensity of acoustic waves sensed by the microphone in a first frequency range.

The air-pulse generating device comprises a film structure, operating at an ultrasonic operating frequency, and a resonant chamber, formed on a side of the film structure. A resonance is formed within the resonance chamber. Due to the resonant chamber, the APG device has a peak on a frequency response of an acoustic property of the APG device at the ultrasonic operating frequency.

The invention discloses a frequency mixing sound demodulator based on a curled structure and a use method thereof in the acoustics field, the demodulator is used for separating frequency mixing sound mixed by a plurality of sound waves with preset frequencies according to respective frequencies, and the demodulator comprises an air waveguide for transmitting the sound waves, and blocking structures arranged on two sides of the air waveguide for blocking the sound waves from penetrating, and a plurality of curled structures that capture corresponding preset frequency sound waves; curled structures are arranged in the barrier structure on at least one side of the air waveguide at intervals, one end of each curled structure is open, and the other side is closed; a plurality of cross beams for blocking penetration of sound waves are arranged in each curled structure, and an internal channel of each curled structure is divided into different lengths to serve as different acoustic resonant cavities so as to capture the sound waves with different frequencies; the closed end of each curled structure is a detection end of each preset frequency sound wave. The invention solves the problem that the existing method is difficult to instantly separate the frequency mixing sound signal and carry out information transmission.

The utility model provides a broadband silencer and an engine air inlet system. The broadband silencer comprises an air inlet pipe, an air outlet pipe, a silencer shell connected between the air inlet pipe and the air outlet pipe, and a resonance sound absorption structure arranged in the silencer shell. The resonance sound absorption structure is made of an elastic vibration material and is configured to be tubular; the resonance sound absorption structure is connected between the air inlet pipe and the air outlet pipe and forms an air inlet channel together with the air inlet pipe and the air outlet pipe. The inner diameter of the silencer shell is larger than the outer diameter of the resonance sound absorption structure, and a silencing cavity is formed between the silencer shell and the resonance sound absorption structure. According to the broadband silencer, elastic vibration of the resonance sound absorption structure enables the silencing cavity to form a resonance cavity, energy of noise is converted into vibration kinetic energy, and therefore the silencing performance of the broadband silencer can be improved.

The invention discloses a perforated plate structure based on Helmholtz and acoustic black holes, which comprises a perforated plate and a bottom rigid wall which are distributed in parallel, and the perforated plate, the bottom rigid wall and an outer side rigid wall are closed to form a resonant cavity; the bottom rigid wall is provided with a plurality of partition plates distributed in a latticed mode, the resonant cavity is divided into a plurality of sub resonant cavities, the perforated plate is provided with a plurality of acoustic black hole structures, and one acoustic black hole structure is arranged in each sub resonant cavity. A round hole is formed in the perforated plate at the central position of the acoustic black hole structure, and the round hole is used as a neck part of the Helmholtz resonance structure; a gap neck exists between the partition plate and the perforated plate, and an acoustic black hole molded line II is arranged on the partition plate. The perforated plate structure can increase the absorption efficiency of sound waves with specific frequency, dissipation is carried out through the damping sound absorption material, an energy absorption-energy consumption trap is formed, the vibration and noise reduction effect is achieved, and meanwhile the sound waves entering the resonant cavity are dissipated again through the gap type Helmholtz resonance structure between the partition plate and the perforated plate.

The embodiment of the invention provides a compressor sound insulation structure and a control method thereof. The compressor sound insulation structure comprises a sound insulation cover and a deformation device. The compressor is covered with the sound insulation cover. The sound insulation cover comprises an inner sound insulation layer and an outer sound insulation layer which are sequentially arranged from inside to outside, and a resonant cavity is formed between the inner sound insulation layer and the outer sound insulation layer; the inner sound insulation layer is provided with a plurality of through holes and is made of a shape memory material; the deformation device is arranged in the soundproof cover and used for receiving the operation frequency of the compressor and driving the inner soundproof layer to deform according to the operation frequency so that the hole diameter of the through hole can be changed. Through the arrangement of the resonant cavity, the intensity of low-frequency noise is gradually weakened under the resonance effect, and therefore effective absorption of the low-frequency noise is achieved; by arranging the deformation device and the inner sound insulation layer made of the shape memory material, intelligent adjustment of the hole diameter of the through hole is achieved, so that the sound absorption frequency of the inner sound insulation layer and the resonant cavity is dynamically adjusted, the noise reduction requirement for broadband noise is met, and the operation noise of the outdoor unit is reduced.

A turbine box provided includes a main body containing a resonant silencing structure, which includes a resonance plate, a resonance chamber wall, and a silencing chamber formed by the resonance plate and the resonance chamber wall. A turbine blower is mounted in the silencing chamber installs, the silencing chamber is open to outside to receive external airflow, and under an action of the turbine blower, the external airflow is transformed into an airflow with a predetermined flow rate. The resonance plate defines a first hole and a second air hole located on opposite sides of the turbine blower; an airflow noise generated by the external airflow entering the silencing chamber, along with an vibration noise generated by the turbine blower, induce a resonance effect between the resonance plate and the resonance chamber wall to dampens both the airflow noise and the vibration noise.

The invention discloses a vehicle warning apparatus. The vehicle warning device comprises a shell, a sound production unit and a net cover, the sound production unit is arranged in the shell, the sound production unit comprises a vibrating diaphragm which vibrates along a vibration axis extending front and back, and the vibrating diaphragm is provided with a front face facing the front and a back face facing the back; the mesh cover covers the front surface of the vibrating diaphragm; the mesh enclosure comprises a fixing ring, a grating part and a shielding part, and the fixing ring is connected with the shell; the grating part is located between the fixing ring and the shielding part, the fixing ring surrounds the grating part, the grating part surrounds the shielding part, and the grating part is provided with a plurality of grating holes for air circulation; a middle hole for air circulation is formed in the middle of the shielding part; and a resonant cavity for changing the sound wave direction is formed between the shielding part and the vibrating diaphragm. The vehicle warning device has high intermediate frequency sensitivity.

The utility model belongs to the technical field of breathing machines, and provides a breathing machine resonance type noise reduction structure and a portable breathing machine, the breathing machine resonance type noise reduction structure comprises a shell, an air duct and a cavity are arranged in the shell, the air inlet end of the air duct is communicated with the outside, and the air outlet end of the air duct is communicated with the cavity; the fan is mounted in the shell, and an air inlet of the fan is communicated with the cavity; the at least one resonance plate is arranged in the air channel and arranged from the air inlet end to the air outlet end, a plurality of through holes penetrating through the resonance plate are formed in the resonance plate, the resonance plate and the inner wall of the shell are spaced to form a resonance cavity, and the resonance cavity is filled with sound absorption materials. According to the resonance type noise reduction structure of the breathing machine, the resonance plate is arranged in the air duct, the resonance cavity is formed by the interval between the resonance plate and the inner wall of the shell, the sound absorption material is filled in the resonance cavity, and the resonance noise elimination of the resonance cavity and the sound absorption of the sound absorption material are combined for noise reduction, so that the good noise reduction effect of the breathing machine is achieved; and the user experience is improved.

The present invention discloses a rail transit sound barrier based on phononic crystal cells, which is divided into several cells of equal volume by dividing modules; a resonance cavity with an opening on one side is embedded in each cell; one side of the opening of the resonance cavity faces the sound source; the opening extends outward in a trumpet shape to increase the sound receiving area; several phononic crystal cells that do not contact each other are fixedly arranged in the resonance cavity; the resonance cavity in the present invention can achieve triple acoustic performance improvements, namely sound insulation, sound elimination and sound absorption: its overall appearance belongs to a Holmhelix resonance cavity, which is itself a good sound elimination device, which is the first sound elimination; the trumpet-like opening structure on the sound source side is conducive to the introduction of sound waves, and the phononic crystal cells are arranged inside, which is the second sound insulation of the device; the tail adopts a boss with the same size as the end of the trumpet mouth, which is conducive to the flow of sound waves, and a certain thickness of sound-absorbing rock wool is used on the inner wall of the tail, which is the third sound absorption.

The invention discloses a strong premixing combustion chamber for restraining combustion noise based on a Helmholtz resonant cavity, and relates to the technical field of energy and power. Air and fuel enter the mixing cavity through corresponding connectors to be strongly premixed, premixed gas enters the hearth to be combusted through slit channels among water cooling channel branch pipes, a water cooling channel array can prevent backfire, the Helmholtz resonant cavity is connected with the hearth through a cavity neck and is provided with an air film cooling channel, the size of the Helmholtz resonant cavity needs to measure combustion noise, and a frequency spectrum is analyzed to obtain characteristic frequency. The neck length, the cross section area and the resonant cavity volume are calculated according to a Helmholtz resonance formula, and the sound absorption effect is verified in combination with a low-order thermoacoustic model. Combustion efficiency is improved through the strong premixing and slit water cooling design, tempering is prevented, NOx is reduced, the diffusion combustion problem is solved, the targeted design resonant cavity is matched with air film cooling, the defects that an existing silencing structure is large in size, poor in adaptation and low in high-temperature reliability are overcome, complex active control is not needed, cost is low, applicability is high, and the application range is wide. And cooperative control of high efficiency, low emission and unstable combustion is realized.

The invention discloses an impedance combined type noise elimination structure parameter design method, which comprises the following steps of: firstly, determining target noise reduction quantity and target sound absorption center frequency of a resistive noise elimination section and a resonant cavity resistance noise elimination section according to noise source characteristics, and then iteratively adjusting structural parameters of the resistive noise elimination section and parameters of the resonant cavity resistance noise elimination section; and until the deviation between the sound absorption center frequency of the resonant cavity and the target sound absorption center frequency is within an allowable range, and the noise reduction amounts of the resistive noise elimination section and the resonant cavity resistant noise elimination section respectively reach the corresponding target noise reduction amounts. According to the method, parameters of the impedance combined type silencing structure can be effectively, rapidly and reasonably determined, and the problem that an existing impedance combined type silencer lacks a systematic method for coordinating multi-target constraints such as silencing performance, airflow resistance and structural strength is effectively solved.

The application discloses a microwave magnetic nozzle thruster without an exciting antenna, belongs to the field of space electric propulsion, and aims at solving the problems of antenna ablation and performance drift of a conventional microwave magnetic nozzle thruster. The microwave magnetic nozzle thruster comprises a discharge chamber and a resonance chamber which are coaxially arranged, a gas inlet pipe is arranged through the center of the thruster in an axial direction, the resonance chamber is coaxially arranged outside the gas inlet pipe, the gas inlet pipe is in communication with the discharge chamber in a gas path, and the gas inlet pipe is isolated from the resonance chamber in a gas path; microwaves are fed into the resonance chamber, repeatedly reflected through a short-circuit end and an open-circuit end of the resonance chamber to generate a standing wave, so that a strong standing wave electric field is formed at the open-circuit end; the strong standing wave electric field ionizes working gas in the discharge chamber to form plasma; the plasma is axially accelerated under a characteristic magnetic field of a divergent magnetic nozzle which is externally applied, forms a plume jet and is ejected out of the thruster, so that a thrust is formed.

The present invention discloses a muffler, which comprises: a waveguide provided with a sound wave inlet; a first resonance cavity and a second resonance cavity arranged along the tube length direction of the waveguide, the first resonance cavity being arranged closer to the sound wave inlet of the waveguide than the second resonance cavity, and the first resonance cavity and the second resonance cavity being Helmholtz resonance cavities; a first neck tube communicating with the waveguide is provided on the first resonance cavity, a second neck tube communicating with the waveguide is provided on the second resonance cavity, and the cross-sectional area of the second neck tube is larger than that of the first neck tube. By arranging two Helmholtz resonance cavities with different cross-sectional areas of the neck tubes on the waveguide, the present invention has a relatively high prediction accuracy of the noise reduction effect. Secondly, the first neck tube and the second neck tube adopt a bent tube design, which can not only ensure a more compact structure, but also is beneficial to low-frequency noise reduction and miniaturization design.

A razor includes one or more blades that are directly or indirectly heated by RF energy. A control circuit is connected to and operates a high frequency (HF) generator and a HF power amplifier (HFPA) for generating radio frequency (RF) energy throughout a range of controllable power levels. The generated RF energy is guided by a wave guide from the HFPA to a resonance chamber (i.e., band pass filter cavity). The RF energy is radiated from the resonance chamber towards the one or more blades which absorb the RF energy, thereby causing the temperature of the blades to increase. An energy source provides the electric current required for operating the control circuit, the HF generator and the HFPA. In another embodiment, the RF energy is radiated from the resonance chamber towards a heating element that increases in temperature and heats the blades by thermal conduction.

The present invention is a washboard instrument with a resonance chamber that improves the overall sound quality produced by the instrument. The resonance chamber improves the amplitude of any sound produced at a considerably lower rate of loss. Further, the instrument was designed to produce a wide variety of different sounds due to the number of different surfaces that can be struck. Additionally, the front panel can accommodate a number of different accessories that include, but not limited to, bells, jam blocks, and cymbals.

Motor vehicle (1, 12, 17) with an interior floor (3) defining a passenger compartment (2) of the motor vehicle (1, 12, 17) on the floor side, at least one electrical energy storage device (4) arranged at least partially on the floor side below at least one section of the interior floor (3), and at least one low-frequency loudspeaker (8, 15, 21) arranged at least partially in the passenger compartment (2), wherein at least one cavity (11) is provided between the interior floor (3) and the electrical energy storage device (4), characterized in that the low-frequency loudspeaker (8, 15, 21) is arranged on at least one opening (18) of the interior floor (3) communicating with the cavity (11) such that the cavity (11) forms a resonance chamber for the low-frequency loudspeaker (8, 15, 21), wherein the opening (18) is on a dome-shaped projection pointing towards the passenger compartment (2). (13, 19) of the interior floor (3) is arranged.

The application discloses a structure and method for inhibiting thermal acoustic oscillation of a gas turbine combustor, relates to the field of inhibiting thermal acoustic oscillation of a gas turbine combustor, and is applied to a combustor and comprises an outer layer pipe and an inner layer pipe, wherein the inner layer pipe is located in the outer layer pipe and the inner layer pipe and the outer layer pipe are coaxial; a back cavity is formed between the inner layer pipe and the outer layer pipe; a plurality of acoustic holes are arranged on the inner layer pipe and the acoustic holes are communicated with the back cavity; the space corresponding to the acoustic holes in the back cavity is a resonance cavity; and each acoustic hole and the resonance cavity form a resonance system. The application can effectively inhibit thermal acoustic oscillation of the gas turbine combustor and reduce the influence caused by the thermal acoustic oscillation.

The utility model relates to an airflow generating device and a breathing machine, the breathing machine comprises the airflow generating device, the airflow generating device comprises a shell and a fan, the shell is internally provided with an inlet cavity, a fan cavity and an outlet cavity which are sequentially communicated in the airflow flowing direction, and the fan is arranged in the fan cavity; the shell is further internally provided with a resonant cavity, the resonant cavity is adjacent to the outlet cavity and the fan cavity and is isolated from the fan cavity, and the cavity wall of the resonant cavity is provided with a plurality of noise reduction holes communicating with the outlet cavity. Noise generated by the fan and noise generated by disordered airflow in the outlet cavity can be transmitted into the resonant cavity through the noise reduction holes, and then the noise is continuously rebounded by the cavity wall of the resonant cavity in the resonant cavity and then is gradually consumed, so that a good noise reduction effect can be achieved without installing noise reduction cotton or sound insulation cotton, the cost can be saved, and the noise reduction efficiency is improved. The assembly process is simplified, fine particles are not generated to harm the body health of a user, and then the use experience of the breathing machine is improved.

The invention provides an inlet silencing device of a turbocharger compressor, a compressor inlet is provided with a plurality of silencing cavities, a vibrating plate of a cantilever is arranged in at least one silencing cavity, at least one electrostatic driver is arranged on a vibrating path of the vibrating plate, local deformation is generated by controlling the electrostatic driver, and the compressor inlet silencing device is used for silencing the compressor inlet. The electrostatic actuator is caused to interfere with the vibration of the vibration plate. The electrostatic driver is arranged in the resonant cavity, the electrostatic driver makes contact with or is separated from the vibrating plate, so that the amplitude of the vibrating plate is changed, and the electrostatic driver and the vibrating plate can be selectively made to make contact with or be separated from each other according to the detected pressure change or noise of an outlet of the turbocharger; and the influence of synchronization impulse noise can be reduced or weakened.

The application discloses a kind of noise elimination and load detection integrated luggage rack longitudinal rods and car, it is related to the field of automobile, including from top to bottom sequentially arranged acoustic noise elimination cavity, vibration isolation structure and load detection structure;The acoustic noise elimination cavity includes a plurality of parallelly arranged resonance cavities, and each resonance cavity is correspondingly provided with a sound hole;The load detection structure is provided with a force transmission bridge or a stress isolation bridge, and a pressure sensor is mounted on the lower side of the force transmission bridge or the stress isolation bridge.The application simultaneously integrates wind noise elimination and load detection functions, to ensure the safety of the use of luggage rack.

This application provides a speaker device and an acoustic structure with a waveguide structure as the rear cavity of a single unit. The acoustic structure with a waveguide structure as the rear cavity of a single unit includes a main speaker enclosure, a waveguide structure, and a dual-sided speaker module. The waveguide structure is disposed within the housing space of the main speaker enclosure and includes a waveguide cavity and a resonant rear cavity connected to the waveguide cavity. The dual-sided speaker module includes a front speaker diaphragm and a rear speaker diaphragm disposed opposite to the front speaker diaphragm. When the second opening is open, the front speaker diaphragm operates to generate a first sound wave, which is guided by the waveguide cavity through the second opening to produce sound, and the resonant chamber of the resonant rear cavity becomes the resonant rear cavity for the operation of the front speaker diaphragm. When the second opening is closed, the rear speaker diaphragm operates to generate a second sound wave, which is guided by the sound channel through the first opening to produce sound, and the resonant chamber of the resonant rear cavity becomes the resonant rear cavity for the operation of the rear speaker diaphragm.

The invention discloses a manufacturing method of a gas outlet pipe assembly of an automobile exhaust emission silencer, and relates to the field of automobile exhaust treatment. The manufacturing method of the air outlet pipe assembly of the automobile exhaust emission silencer comprises the five steps of material pretreatment, internal high-pressure forming, punch forming, assembly assembling and intelligent integration. According to the invention, through the combination of the double-circulation noise reduction design and the variable volume resonant cavity, the noise reduction performance is obviously improved; specifically, broadband noise reduction is achieved, specifically, high-frequency noise is effectively reduced through the double structure of the circulating pipe and the spring-shaped pipe, and the low-frequency noise treatment effect of the resonant cavity is further optimized by adjusting the shape of a cavity body and distribution of partition plates; vibration suppression: multiple layers of sound insulation cotton are embedded into the inner wall of the air outlet pipe, and an elastic connecting sleeve is combined, so that vibration transmission is effectively reduced, and the silencing effect is further improved; the design is not only suitable for traditional fuel vehicles, but also suitable for new energy hybrid vehicles, and diversified market requirements are met.

The air-pulse generating device comprises a film structure, operating at an ultrasonic operating frequency; and a resonant chamber, formed on a side of the film structure. A resonance is formed within the resonance chamber. Due to the resonant chamber, the APG device has a peak on a frequency response of an acoustic property of the APG device at the ultrasonic operating frequency.

Disclosed herein is a meta-muffler for reducing broadband noise. The meta-muffler includes: a flow pipe through which a fluid flows; an outer barrel disposed outside the flow pipe to be spaced apart from the flow pipe; and multiple metastructures arranged in a flow direction of the fluid and each comprising an opening opened parallel to the flow direction of the fluid, a resonance chamber disposed between the flow pipe and the outer barrel and communicating with the flow pipe through the opening, and a neck adjustment member extending from the outer barrel toward the flow pipe to be spaced apart from the opening in the flow direction of the fluid. The meta-muffler can increase transmission loss of noise flowing through the flow pipe through maximization of energy loss of sound waves entering the resonance chamber of the metastructure and can effectively attenuate noise over a wide band ranging from low frequencies to high frequencies.

The invention discloses a resonance chamber vibration quantity increasing device. The resonance chamber vibration quantity increasing device comprises a fixing mechanism fixedly connected with a resonance chamber body and a string supporting cross beam fixed to the fixing mechanism. And the string supporting cross beam is arranged above the resonator panel between the lower bridge of the resonator and the bottom of the resonator body. The resonance box has the advantages that the independent string supporting device is arranged, the force of strings applied to the resonance box panel through the lower bridge of the resonance box is shared, the resonance box panel can be made to be very thin, the vibration amplitude of the resonance box panel is improved, the vibration volume of the resonance box is greatly improved, the volume of the resonance box type musical instrument is greatly improved, and the resonance box type musical instrument is more attractive in appearance. The tone expressive force is greatly improved, the sound is more transparent and loud, the high pitch is more penetrable, and the low pitch is more vigorous. As the string supporting device shares the pressure of most strings, the pressure of the panel is released, and the service life of the resonator is greatly prolonged.

The application discloses a high-pressure shell assembly for an electric compressor, an electric compressor, an air conditioning system and a vehicle, and relates to the technical field of electric compressors. The high-pressure shell assembly comprises a high-pressure shell, a high-pressure cavity and a refrigerant discharge port are formed on the high-pressure shell, a compression component of the electric compressor is adapted to discharge compressed refrigerant to the high-pressure cavity, and the refrigerant discharge port is used for discharging refrigerant outside the high-pressure shell; a resonance cavity and an oil separation cavity which are in communication with each other are further formed on the high-pressure shell, the oil separation cavity is in communication with the high-pressure cavity to receive refrigerant flowing out of the high-pressure cavity, a sound attenuation nozzle is arranged in the resonance cavity, a flow-through channel is defined between the sound attenuation nozzle and the inner wall surface of the resonance cavity, one end of the cavity in the sound attenuation nozzle is in communication with the refrigerant discharge port, and the sound attenuation nozzle is provided with a sound attenuation hole which is in communication with the cavity and the flow-through channel. The high-pressure shell assembly for the electric compressor can eliminate noise and pressure pulsation accompanied by gaseous refrigerant, and has good sound attenuation effect.

The present invention generally concerns an adjustable pneumatic device that creates sound. More specifically, the present invention improves diaphragm-based air horns by having a unique base with an extended pressure chamber, an adjustable volume lever, a tunable shaft that generates specific tonal pitches, and an optional sound amplification plate. The horn includes: an inverted closet flange, an annulus pressure plate, a pressure relief tube, a bushing connector, a collar coupling, an air inlet system, a flexible diaphragm, a resonator, rivets, screws, an optional sound amplification plate, and an air pump. Within the pressure chamber, a tube presses against a diaphragm via tension, causing the diaphragm to stretch beyond the lower portions of the base's bottom most surface. Compressed air traverses chamber spaces around the tube and about the extended pressure chamber to trigger diaphragm vibrations that generate sound at the resonator from 109 decibels to 129 decibels.

The utility model discloses an electronic expansion valve and refrigeration plant relates to electronic expansion valve technical field, this electronic expansion valve includes valve body, transmission subassembly, valve needle and mounting seat, and valve body has the valve mouth, transmission subassembly includes nut and screw rod, and nut is sealedly connected with valve body, and screw rod is cooperated with the nut thread, valve needle is connected with screw rod, and can be axially removed to open or close the valve mouth, and the circumferential side of mounting seat is sealedly connected with the inner wall of valve body, and the resonance cavity is defined between mounting seat and nut, and the valve cavity that communicates valve mouth is defined with valve body and mounting seat, and mounting seat has the guide channel that is arranged coaxially with nut, and valve needle is worn guide channel and is matched with the clearance of guide channel, wherein, mounting seat still is equipped with the sound -absorbing passage that communicates resonance cavity and valve cavity. The utility model provides technical scheme to utilize mounting seat and divide resonance cavity and valve cavity, and construct the sound -absorbing ware structure through resonance cavity and sound -absorbing passage to reduce the noise that high pressure refrigerant produces in the flow process in valve cavity because of the flow rate mutation.

The invention discloses a noise reduction structure for a vacuum pump, the noise reduction structure comprises a resonance box, the resonance box is provided with a plurality of resonance cavities arranged side by side, the plurality of resonance cavities are communicated in sequence, and vibration noise in the vacuum pump is spread outwards through a pump body outlet and enters the plurality of resonance cavities. Sound waves generate resonance and counteract under the action of the multiple resonant cavities which are communicated with one another, so that the amplitude of the sound waves is weakened. In the invention, the two adjacent resonant cavities are sequentially communicated through the non-return channel and the flow guide channel, and the opening, communicated with the flow guide channel, of the same resonant cavity and the opening, communicated with the non-return channel, of the same resonant cavity are arranged at intervals, so that airflow and vibration noise are subjected to direction change and path extension for many times in the flowing process; the complex flowing mode not only further weakens sound waves and reduces vibration noise through multiple times of reflection and interference, but also can quickly weaken the airflow velocity and reduce aerodynamic noise generated by airflow impact, and effectively weaken the noise level in the operation process of the vacuum pump.