19results about How to "Improve the noise reduction effect" patented technology

This invention relates to a low-noise optical module three-temperature testing device, comprising a test box with a test cavity formed inside. An air inlet pipe is connected to the test box and communicates with the test cavity. A first silencing cavity is also formed inside the test box, and a first exhaust channel communicating with the first silencing cavity is provided on the test box. A duct is also connected to the test box, connecting the test cavity and the first silencing cavity. By setting up the first silencing cavity and connecting it to the test cavity via the duct, this invention not only extends the gas flow path within the test box and serves to store airflow, but also significantly increases the gas flow area and the diffuse reflection area and number of reflections within the test box, thereby reducing gas velocity and noise energy, achieving noise reduction. The test cavity-duct-first silencing cavity can form a Venturi effect, resulting in better noise reduction.

The utility model discloses a kind of ceiling fastener, sound attenuation voltage regulator and sound attenuation shell, including sound attenuation spacer and heat insulation sleeve, there is deslagging gap between two, sound attenuation spacer is equipped with first deslagging hole, front plugging step, rear plugging step and multiple partition steps, step structure separates first, second deslagging passage and is connected by communicating passage, there is deslagging outlet in the outer ring of front plugging step, first deslagging hole is located in first deslagging passage close to front plugging step side.This design makes ash discharge path zigzag, effectively prolongs deslagging distance, significantly enhances sound attenuation effect;At the same time, the partition step is arranged in the sound attenuation spacer, which reduces the processing difficulty, reduces the working hours and cost, and improves the product competitiveness;The extended deslagging path also buffers the ash speed, avoids high-speed injection, and improves the use safety.

This application provides a muffler, belonging to the field of vehicle technology. The muffler includes a housing, chamber partitions, an intake pipe, a muffler pipe, an exhaust pipe assembly, and a switching valve. The housing and multiple chamber partitions located within the housing enclose multiple muffler chambers arranged sequentially along the length of the housing. The expansion muffler chamber is connected to the intake pipe, and the expansion muffler chamber and the Helmholtz muffler chamber are connected through a muffler pipe located within the housing. The exhaust muffler chamber is located downstream of the expansion muffler chamber along the exhaust path of the muffler, and is connected to the outside of the housing through the exhaust pipe assembly. An exhaust passage is used to connect the expansion muffler chamber and the exhaust muffler chamber. The switching valve is used to open or close the exhaust passage. The expansion muffler chamber is located between the exhaust muffler chamber and the Helmholtz muffler chamber. The muffler of this application embodiment can meet the noise reduction requirements of the engine under different operating conditions and improves the reliability of engine noise reduction under high back pressure.

The utility model discloses a ventilation sound -absorbing device and energy storage heat management system belongs to the technical field of silencer, and is designed for solving the inconvenient of existing silencer dismounting, transportation etc. The utility model discloses a ventilation sound -absorbing device includes: frame, including the two end plates and two side plates for surrounding ventilation pipeline, and each end plate is detachably connected between two side plates, and sound -absorbing piece is located in ventilation pipeline and is detachably connected to the side plate, and sound -absorbing piece includes shell and the composite sound -absorbing inner core of setting in the shell, and the composite sound -absorbing inner core includes at least three layers of sound -absorbing layer of sequentially adhering settings, and the material density of outside sound -absorbing layer is lower than the material density of internal sound -absorbing layer. The utility model discloses a ventilation sound -absorbing device and energy storage heat management system, and the dismounting is convenient, and the transportation difficulty is low, and the composite sound -absorbing inner core can simultaneously absorb the noise of medium -high frequency and low frequency, solves the problem that the existing silencer can only handle medium -high frequency noise, and the noise reduction effect is good.

The utility model relates to feed cooling fan technical field, and disclose a kind of silencing device for poultry feed cooling fan, the inside of load-bearing seat is provided with silencing mechanism, the top of silencing mechanism is provided with cooling fan body, the bottom of silencing mechanism is provided with damping mechanism, the silencing mechanism includes load-bearing plate, the inside of load-bearing seat is slidably connected, the bottom of load-bearing seat is fixedly connected with arc plate on two sides, the inside of arc plate is fixedly connected with linkage rod, the periphery of linkage rod is rotatably connected with rotating plate, the bottom of rotating plate inside is rotatably connected with connecting rod, the two sides of connecting rod are fixedly connected with U-shaped plate. Rotating plate rotates on linkage rod, and U-shaped plate and sliding block are slid on fixed rod by connecting rod, sliding block slides and compresses or stretches first spring, first spring absorbs and buffers vibration energy by deformation, reduce the noise generated in vibration transmission process.

The present application relates to internal combustion engine, specifically provide a kind of muffler for aviation internal combustion engine and aviation internal combustion engine, to solve the problem that the exhaust muffler of existing internal combustion engine is too large in size and too heavy in weight, not suitable for the needs of low-altitude aircraft.For this purpose, the muffler of the present application includes air inlet, air outlet and multiple layers of pleated partition, air inlet and air outlet form airflow passage, multiple layers of pleated partition are arranged in airflow passage in spaced-apart, each layer of pleated partition is configured to scatter, reflect, refract and diffract the sound waves of airflow, multiple layers of pleated partition are configured to continuously reflect and refract sound waves in multiple stages, so that sound waves collide with each other to cancel sound energy and reduce sound intensity, so that sound energy concentrated sound waves are scattered and attenuated step by step when passing through multiple layers of pleated partition, so that the muffler of the present application has obvious noise reduction effect, and the muffler of the present application is made of metal 3D printing, so that the effect of small size and light weight can be realized.

The utility model discloses a spliced pipeline elbow muffler, the muffler is installed to the outside of pipeline elbow, the muffler includes: along the first muffling piece and second muffling piece of pipeline elbow center symmetry plane symmetry installation, first muffling piece and second muffling piece form the muffler in the combination, first muffling piece includes the shell and sets up first sealing plate and second sealing plate at the both ends of shell, and the first sealing plate and second sealing plate form the sound attenuation chamber at the inboard of shell, and the sound attenuation chamber is movably connected with the sound attenuation assembly through the connecting component, and the sound attenuation chamber is used for filling sound attenuation material between the sound attenuation assembly and shell, the utility model provides detachable muffler, and first, second cover body is butt joint through the positioning column / groove, and the flange is fixed, and the installation is convenient, and the sound attenuation chamber fills the elastic material and cooperates the sound attenuation assembly of multilayer and promotes the sound attenuation effect, and the connecting component is hinged with the shell, and the elastic sound attenuation assembly can self -adaptation and is wrapped different diameter elbow, and the applicability is wide.

The utility model provides a kind of engine system and motorcycle, wherein, engine system includes: engine, the engine is set to the rear of motorcycle inclination, and the engine is provided with air inlet and air outlet;Silencer component is connected with the air outlet of the engine, and extend towards the tail of motorcycle after around the engine one week.This scheme effectively improves the compactness of structure by the reasonable layout of engine and silencer component, adjusts the gravity center of motorcycle by changing the inclination direction of engine.

This utility model relates to the field of noise reduction device technology, specifically to a replaceable sound-absorbing cotton type fan silencer. The silencer includes an inner cylinder and an outer cylinder, which together enclose a mounting cavity. The inner cylinder has several mounting openings along its circumference that communicate with the mounting cavity. Several movable perforated plates, corresponding one-to-one with the mounting openings, are hinged to the inner side of the inner cylinder. The movable perforated plates can cover the corresponding mounting openings. The free ends of the movable perforated plates are detachably connected to the inner cylinder. A first sound-absorbing cotton is provided inside the mounting cavity. When it is necessary to replace the sound-absorbing cotton, simply detach the free ends of the movable perforated plates from the inner cylinder to open the mounting openings, and then remove the first sound-absorbing cotton from the mounting openings for easy replacement.

The utility model discloses a special silencer for an electromagnetic valve, and particularly relates to the technical field of electromagnetic valve silencing, which comprises an electromagnetic valve main body, a silencing horn mouth is arranged on one side of the electromagnetic valve main body, a silencing mechanism is arranged on one side of the silencing horn mouth, and the silencing mechanism comprises a first silencing component and a second silencing component. The first silencing assembly comprises a first silencing frame, a side plate and two first baffles, the side plate is fixedly arranged on the outer side of the first silencing frame in a sleeving mode, and the two first baffles are both fixedly installed on one side of the interior of the first silencing frame. The purge gas in the silencing horn mouth penetrates through the silencing horn mouth and enters the first silencing frame, the purge gas in the first silencing frame enters the second silencing frame through the first exhaust port, first reduction of the airflow speed can be achieved, and finally the purge gas is exhausted through the second exhaust port. The silencer is simple in structure, double-layer silencing is achieved, and the overall silencing effect is effectively improved.

This invention discloses an integrated muffler and exhaust device for unmanned aerial vehicles (UAVs), belonging to the field of aircraft configuration technology. It includes a muffler cavity, mounting brackets on the four sides of the top of the muffler cavity, a soft isolation layer on top of the mounting brackets, an air intake pipe on top of the muffler cavity, and a middle section bracket at the center of the muffler cavity. The middle section bracket and a support partition separate the muffler cavity into a silencing space. The outer end of the guide pipe and the end of the exhaust pipe extending out of the support partition are both located within the silencing space, where a loudspeaker is installed. An exhaust sluice pipe is connected to the bottom of the muffler cavity and corresponding to the position of the silencing space. An exhaust adjustment mechanism is also provided on the muffler cavity and the guide middle section, and a control mechanism is provided on one side of the top of the muffler cavity. The operation of the exhaust adjustment mechanism is controlled by analyzing the noise wave fluctuations. This device is suitable for effective noise reduction of two-stroke engines at different operating speeds.

The application discloses a kind of active noise cancellation device for ventilation duct, including ventilation duct and installation plate being arranged on ventilation duct, the ventilation duct includes first pipe and second pipe, the opposite side of the outer surface of first pipe and second pipe is all welded and fixed with butt joint frame, the both sides of installation plate are all penetrated and slidably installed with first L-shaped positioning frame, and the application relates to noise control technical field.The active noise cancellation device for ventilation duct provides the abutment of the abutment of two butt joint frames with the setting of two first L-shaped positioning frames, first rubber sleeve, first butt joint groove, installation plate and first fastening bolt, and provides fixing condition for detection box, to ensure that active noise eliminator is effectively used in ventilation duct, and cooperate with the setting of telescopic air cylinder, noise reduction frame and cover plate, when ventilation duct is not used, active noise eliminator can be isolated and protected by cover plate, to avoid the influence of dust on active noise eliminator.

The utility model relates to a related field of silencing assembly, especially a fan air inlet silencing assembly, including outer frame, silencer, support frame, silencing louver, filter screen, damping plate, first sound insulation board and sound insulation roof plate etc.

This utility model discloses a prefabricated moisture-proof and sound-absorbing ceiling, which includes a series of arc-shaped sound absorbers. The arc-shaped sound absorbers are connected to the top beam or floor slab via stainless steel hangers. The arc-shaped sound absorbers include three types: an upwardly concave sound absorber, a first downwardly convex sound absorber, and a second downwardly convex sound absorber. Each upwardly concave sound absorber is adjacent to a first downwardly convex sound absorber and a second downwardly convex sound absorber on both sides, forming an overall wave shape. Each arc-shaped sound absorber includes sound-absorbing cotton, a moisture-proof cloth, and an aluminum plate. This utility model offers excellent moisture and corrosion resistance, good sound absorption, strong structural integrity, and convenient construction.

This utility model discloses a silencing device for a vacuum pump, including a cylindrical body. Two partitions are arranged inside the cylindrical body from top to bottom, dividing the cylindrical body into a first chamber, a second chamber, and a third chamber from top to bottom. An air inlet pipe is connected to the first chamber, and the first and third chambers are connected by a first connecting pipe. The second and third chambers are connected by a second connecting pipe, and an exhaust pipe is connected to the second chamber. This relates to the field of silencing structure technology. The cylindrical body is divided into a first chamber, a second chamber, and a third chamber from top to bottom by partitions. An air inlet pipe is connected to the first chamber, and the first and third chambers are connected by a first connecting pipe. The second and third chambers are connected by a second connecting pipe, and an exhaust pipe is connected to the second chamber. Gas diffuses and flows along the first, third, and second chambers within the silencer. During the reciprocating flow within the path, the energy of the gas is consumed, resulting in better performance.

The utility model provides a kind of exhaust soundproofing shroud, including shroud main body, soundproof board and exhaust sound reduction component.The shroud main body is equipped with protective space and air inlet space inside.The soundproof board is at least two pieces, and staggered and spaced installation is formed between the protective space and air inlet space zigzag or circuitous air inlet passage, and the air inlet space is equipped with air inlet louvre.The exhaust sound reduction component includes air inlet pipe, muffler and exhaust pipe communicated sequentially, the air inlet end of air inlet pipe extends into protective space, and the exhaust end of exhaust pipe extends to the accommodation opening of shroud main body peripheral wall.The exhaust soundproofing shroud provided by the utility model forms zigzag or circuitous air inlet passage between protective space and air inlet space by the soundproof board, on the basis of not affecting air inlet, most of noise emitted by engine can be resisted and absorbed, reduce the transmission of noise, in addition, the muffler can also absorb noise carried by engine exhaust, further improve the sound reduction effect.

This invention discloses a low-frequency ventilation and noise reduction structure for a prefabricated substation, comprising a shell, multi-stage side-supported resonant sound absorbers, a main ventilation duct, a composite sound-absorbing layer, and a constrained damping layer. The shell has an air inlet and an air outlet. The main ventilation duct is formed inside the shell and runs through the airflow direction from the air inlet to the air outlet. The multi-stage side-supported resonant sound absorbers are located circumferentially or axially outside the main ventilation duct and are connected to the main ventilation duct through a neck channel. The composite sound-absorbing layer is located on the inner wall of the main ventilation duct, and the constrained damping layer is located on the inner side of the shell. Each stage of the side-supported resonant sound absorber has a different cavity volume, neck cross-sectional area, and equivalent neck length to absorb noise in different low-frequency bands. This invention, while maintaining the unobstructed ventilation and heat dissipation channels of the prefabricated substation, can achieve multi-peak coupling noise reduction for low-frequency noise in the 50~200Hz range, while also considering low voltage loss, compact structure, convenient installation, and adaptability to outdoor operation.