42results about How to "Reduce high frequency noise" patented technology

The invention provides a lace texture image diffusion generation method based on an ADM and a dynamic denoising filtering model, the model combines a learnable Gaussian blur layer and a high-pass filtering technology, and the Gaussian blur layer aims at adaptively adjusting the blur degree of the image according to different input images and reducing high-frequency noise in the lace texture image. According to the high-pass filtering technology, key areas such as the contour and the edge of a main pattern in the image are enhanced, so that main texture features of the image are highlighted. The module is added into a down-sampling layer of an ADM network, the phenomenon that lace texture images generated by an original model are too smooth is improved, and the texture layering sense of the images is enhanced.

The invention relates to an ultrasonic fluid metering precision improving method and related equipment, and the method comprises the steps: exciting a first ultrasonic transducer through an excitation wave sequence, enabling a second ultrasonic transducer to work, obtaining a received digital signal corresponding to the excitation wave sequence, and calculating the signal-to-noise ratio of the received digital signal; wherein the excitation wave sequence is a combination of a main wave and a self-damping wave, and the signal-to-noise ratio is a ratio of a peak-to-peak value of a receiving signal area to a peak-to-peak value of a noise area; judging whether the signal-to-noise ratio is greater than a signal-to-noise ratio threshold value or not, if not, adjusting the occupation time of the high and low levels of the self-damping waves, and executing the excitation work again according to the adjusted excitation wave sequence until the actual signal-to-noise ratio is greater than the signal-to-noise ratio threshold value; and determining the corresponding excitation wave sequence when the actual signal-to-noise ratio is greater than the signal-to-noise ratio threshold as a target excitation wave sequence, and exciting the ultrasonic transducer to work according to the target excitation wave sequence so as to execute metering operation. According to the method, the measurement precision is remarkably improved while the hardware cost is not increased.

The invention provides a control method of an air conditioner, a controller, the air conditioner and a medium. The control method comprises the steps that the load index of each indoor unit in a running state from the starting moment to the current moment is obtained; screening out a maximum load index and a minimum load index from the plurality of load indexes; according to the maximum load index, the minimum load index and the first target saturation temperature of the refrigerant in the current control period, the second target saturation temperature of the refrigerant in the next control period is determined; and the actual saturation temperature of the refrigerant of each indoor unit in the next control period is detected, and the operation parameters of the air conditioner are controlled according to the actual saturation temperature and the second target saturation temperature. According to the invention, the real-time load can be identified and calculated based on the control error, the elimination of the indoor load is taken as a final target, the target saturation temperature is adjusted, the system output is adjusted along with the change of the load index, the frequent starting and stopping noise and the frequency rising and high-frequency noise during starting can be reduced under the low load, and the comfort is improved.

The invention relates to the field of portable heat dissipation, in particular to a neck-hanging fan which comprises a fan, a ventilation channel, a first air inlet and a first air outlet, the first air inlet and the first air outlet are communicated with the ventilation channel, and the fan is arranged in the ventilation channel. The fan runs, air flow penetrating through the ventilation channel is formed between the first air inlet and the first air outlet, and the direction of the rotating center axis of the fan is consistent with the direction of the air flow; at least two silencing devices are arranged in the ventilation channel, at least one silencing device is arranged between the first air inlet and the draught fan, and at least the other silencing device is arranged between the draught fan and the first air outlet. The neck-hanging fan can achieve the effects of high wind speed and low noise, and can effectively reduce the influence of high-frequency noise on a user so as to improve the user experience.

This utility model relates to the field of pipeline technology, specifically to a compressor venting and noise reduction pipeline and its noise reduction system. The compressor venting and noise reduction pipeline includes: an exhaust pipeline, a bend downstream of the exhaust pipeline, a branch pipeline downstream of the bend, an output pipeline downstream of the branch pipeline, and a silencer downstream of the output pipeline. The silencer includes a spiral flow guiding device. This utility model reduces the velocity of the medium flow by using the bend, branch pipeline, and silencer, consuming part of the kinetic energy of the medium flow, thereby reducing the noise generated by the medium colliding with the pipe wall during discharge and reducing the safety risks to on-site personnel.

The invention discloses an audio signal generation device and method, relates to the technical field of acoustic measurement, and solves the problems of single function, low output amplitude frequency, low signal quality and high cost of an audio signal generator in the prior art. According to the method, a main control unit, an audio data playing unit, a multi-stage low-pass filter unit and a program control precision attenuator unit are included, a digital signal processing technology is adopted, a hardware circuit is simplified, the hardware cost can be reduced, multiple audio signal generation functions are included, the performance is excellent, and the method can be suitable for multiple scenes. The tail-stage amplification circuit adopts a filter design thought, supports output of high-frequency sinusoidal signals and reduces high-frequency noise in the circuit at the same time, so that the total distortion of the output signals is as low as 0.01% or below within the frequency range of 10-40 kHz, the highest output frequency is increased to 1 MHz, the lowest output frequency reaches 0.05 Hz, and the verification requirements of octave and fractional octave filters are met.

The utility model provides a holding circuit and a charging device. The holding circuit comprises a power failure holding module. The power failure holding module comprises a first capacitor and a first diode; the first end of the first capacitor is connected with the anode of the first diode, and the second end of the first capacitor is connected with the cathode of the first diode; the first end of the first capacitor is also used for being connected with a low potential output end of a power supply module, and the second end of the first capacitor is also used for being connected with a high potential output end of the power supply module; wherein a low potential output end and a high potential output end of the power supply module are respectively connected with a load. According to the holding circuit, the diode and the capacitor are connected in parallel to form a quick discharge circuit, so that the discharge efficiency is improved, and the stability and the integrity of data in a load are improved.

The utility model discloses a wired earphone with an external microphone module, which is characterized in that a microphone unit is detachably connected with a mounting seat, and a blowout prevention protective sleeve is sleeved outside the microphone unit, so that the direct impact of airflow on the microphone unit can be reduced, the'spouting sound 'generated by breathing airflow can be effectively filtered, and compared with the traditional wired earphone, the wired earphone has the advantages of simple structure and convenience in use. The wired earphone provided by the utility model can keep human voice details while attenuating high-frequency noise, and is especially suitable for outdoor communication scenes.

The utility model belongs to the technical field of brushless motors, in particular to a plastic shell motor structure, which comprises a rotor, a stator and a plastic shell integrally formed by injection molding, the radial section of the plastic shell is W-shaped, and the plastic shell comprises an outer shell part and an isolation part which completely isolate the rotor from the stator. An opening for assembling the rotor and the stator is formed in one side, opposite to the isolation part, of the shell part; when the stator and the rotor are fixed by the plastic shell, the stator and the rotor are separated, due to the rigid design of the plastic shell, accurate positioning of the stator and the rotor can be ensured, uniform air gaps between the stator and the rotor are ensured, and vibration, noise and efficiency reduction caused by eccentricity are avoided; the plastic shell can enhance the insulation grade and can meet the double insulation design, and the power can be higher under the same condition; even if more enameled wires are wound on the stator to increase the power of the motor, the stator still meets the safety requirement of the electrical clearance, so that the motor can safely operate under higher power.

The present invention discloses a robot trajectory planning method, device and electronic equipment, which relates to the field of robot technology. The method includes: obtaining the original discrete points corresponding to the robot, wherein the original discrete points include time and position; based on the time and position of the original discrete points, screening out at least two target inflection points in the original discrete points; determining the abnormal data points in the original discrete points, and processing the abnormal data points based on the target inflection points to obtain the target key points of the robot; performing trajectory planning and interpolation of the robot according to the trajectory planning parameters and the target key points to obtain the target trajectory of the robot. The technical solution of the present invention greatly eliminates the number of discrete points, retains some key points, reduces the amount of calculation and the high-frequency noise of acceleration, and at the same time, because the key points are preserved, the degree of fit between the planned trajectory and the original trajectory can be guaranteed.

The invention discloses a sensitivity gain electrode array electrochemical particle vibration velocity sensor and an implementation method thereof. The gain electrode array is arranged, so that the sensitivity of the device can be greatly improved; each gain electrode is respectively connected in series with a corresponding switch to be connected to a zero potential, the measuring range of the device can be adjusted, and different numbers of gain electrodes are connected, so that the measuring ranges are different, and different application scenes can be adapted; according to the invention, the utilization rate of the electrolyte is improved, the electrolyte far away from the chip can be more effectively utilized, and the ion concentration on the surface of the anode is effectively improved; the device has universality for equipment such as a vibration detector-wave detector or a hydrophone based on an electrochemical principle, and the sensitivity of the equipment can be effectively improved under the condition of not increasing additional process steps; high-frequency noise of a device can be reduced, the trend of a high-frequency noise curve is improved, and great significance is achieved for underwater application scenes; the system is low in cost and outstanding in gain effect, and can be used in a superposed manner to further improve the sensitivity.

The invention discloses an effective signal extraction method and system based on CVAE, and relates to the field of digital signal processing, and the method comprises the specific steps: constructing a conditional variation auto-encoder which comprises an encoder, a re-parameterization module and a decoder; constructing a training data set based on the observation data set and the corresponding conditional variable set; training the conditional variation auto-encoder by using the training data set, and performing parameter optimization on the conditional variation auto-encoder by using a loss function based on physical consistency constraint; the loss function based on the physical consistency constraint comprises a reconstruction error item, a KL divergence loss item and a physical constraint loss item; acquiring to-be-processed data and corresponding conditional variables; and inputting to-be-processed data and conditional variables into the trained conditional variation auto-encoder to obtain effective signals. According to the method, physical consistency constraint is introduced through the conditional variation auto-encoder, high-frequency noise and pseudo-frequency components are effectively weakened, and a reconstructed signal is closer to a real signal.

The utility model discloses a high-efficiency full-magnetic direct-current motor control circuit, which comprises a direct-current bus DC +, a direct-current cathode DC-, an IGBT (Insulated Gate Bipolar Transistor) chopping voltage-regulating element Q on the direct-current bus, a three-phase or multi-phase full-bridge control circuit, a full-bridge commutation control circuit consisting of four IGBT switching elements K1 / K2 / K3 / K4 in each phase of full-bridge control circuit, and a phase winding for controlling a motor, and a Buck circuit consisting of a capacitor C1, an inductor L1, a diode D1 and a diode DA is also arranged in front of each phase of full-bridge commutation control circuit. The utility model relates to the technical field of full-magnetic direct current motor control, direct current power supply enters a motor winding after being subjected to high-frequency chopping voltage regulation and voltage stabilization by the Buck circuit, and the current entering the motor winding does not contain high-frequency characteristics, so that the direct current power supply is stable and stable. The high-frequency noise of the motor can be effectively reduced, meanwhile, the capacitor C1 can absorb counter potential energy in the motor winding, the counter potential energy is released into the motor winding again through the Buck circuit, and the mechanical efficiency of the motor is greatly improved through the counter potential energy.

The invention belongs to the technical field of active magnetic field compensation systems, and discloses an active magnetic compensation control system and method based on magnetic field multi-source disturbance suppression, and the system comprises an ADC collection unit, a DAC output unit, a controller, a high-precision current source, a magnetic compensation coil, a magnetic field sensor, and a TD-Smith advanced predictor. And enhancing a model-assisted extended state observer (AMESO) and a filter equivalent setting method. By adopting the technical scheme of the invention, the real-time estimation accuracy of external magnetic field disturbance can be obviously improved, the influence of magnetic field multi-source disturbance on the internal magnetic field of the magnetic shielding device is inhibited, the uniformity and stability of the internal magnetic field of the magnetic shielding device are improved, and the method is suitable for realizing high-precision control of the extremely low-intensity magnetic field.

The utility model discloses a rotor, a motor, a compressor and refrigeration equipment, and relates to the technical field of motors, the rotor comprises a rotor iron core, and the rotor iron core at least comprises a first rotor punching sheet, a second rotor punching sheet and a third rotor punching sheet which are laminated along the axial direction of the rotor iron core; the number of the first rotor punching sheets is multiple, the two ends of the rotor iron core are each provided with at least one first rotor punching sheet, and the second rotor punching sheet and the third rotor punching sheet are located between the two first rotor punching sheets arranged at the two ends of the rotor iron core respectively. The rotor iron core is provided with air slots located between two adjacent magnetic steel slots, and the air slots comprise a plurality of first air slots arranged on the first rotor punching sheet, a plurality of second air slots arranged on the second rotor punching sheet, and a plurality of third air slots arranged on the third rotor punching sheet; in the axial direction of the rotor core, the plurality of second air slots and the plurality of third air slots are at least partially staggered and are in one-to-one correspondence with the first air slots; according to the technical scheme provided by the utility model, high-frequency noise of the motor can be reduced.

The application discloses a kind of analysis and prediction methods of high-frequency noise of pod propeller, comprising the following steps: S1, obtain the flow field original data and corresponding high-frequency noise monitoring data under the working state of pod propeller, and pre-process;S2, based on the separated vortex model, construct flow field-noise coupling analysis framework, set the time step and calculation frequency matched with actual working condition, the present application relates to ship propeller noise analysis and prediction technical field.The analysis and prediction method of high-frequency noise of the pod propeller, by constructing flow field-noise coupling analysis framework, the pre-processed flow field data are processed, the vortex structure characteristics of flow field can be captured, and based on the correlation mechanism of vortex structure and noise generation, the contribution of each vortex unit to high-frequency noise is accurately calculated, the vortex unit of dominant noise source is screened, and the dynamic positioning of high-frequency noise source is realized in combination with its space-time position information, which helps to understand the root of noise generation.

The embodiment of the invention provides a motor and an assembling method of the motor, and the motor comprises the components of a rotor which comprises a rotating shaft which rotates with a central axis as a center, a rotor frame which is arranged at the axial upper end of the rotating shaft and rotates along with the rotating shaft, and a magnet which is configured on the rotor frame; and a stator; the motor further comprises a first fixing part which is arranged between the rotor frame and the magnet and is used for preliminarily fixing the rotor frame and the magnet; and the second fixing part is arranged between the rotor frame and the magnet, and performs secondary fixing on the rotor frame and the magnet after the first fixing part performs the primary fixing. Therefore, after the rotor frame and the magnet are primarily fixed through the first fixing part, the rotor frame and the magnet are secondarily fixed through the second fixing part, the situation that the coaxiality is reduced due to the fact that the rotor frame and the magnet deviate in the secondary fixing process is avoided, and therefore high-frequency noise generated when the motor operates is reduced.

This utility model discloses a sound absorption and noise reduction structure for a vacuum cleaner, including an airflow channel pipe. One end of the airflow channel pipe is snapped into a vacuum cleaner connector. Dust chamber shell one and dust chamber shell two are respectively attached to both sides of the airflow channel pipe. The mating surfaces of dust chamber shell one and dust chamber shell two are snapped into each other, and a handle ring is snapped into the outer side of the dust chamber shell one near the vacuum cleaner connector end, and a limit ring is snapped into the outer side of the dust chamber shell one away from the handle ring end. A dust chamber shell cover is snapped into the top of dust chamber shell one and dust chamber shell two. Heat dissipation holes are opened on the bottom side of each dust chamber shell one and dust chamber shell two, and a motor assembly is fixedly connected inside the corresponding heat dissipation holes. Through the integrated design of airflow channel optimization, vibration isolation, composite noise reduction and efficient heat dissipation, the acoustic performance of the vacuum cleaner is improved while ensuring heat dissipation efficiency and structural reliability, achieving a comprehensive technical effect of low noise and high stability.

The tail gas post-treatment device comprises a nitrogen and oxygen detection device fixed to the inner wall of a post-treatment gas outlet pipe, the nitrogen and oxygen detection device comprises a nitrogen and oxygen sensing device and a perforated plate, and the nitrogen and oxygen sensing device is located on the gas inlet side of the perforated plate; the distance between the nitrogen and oxygen sensing device and the perforated plate is smaller than or equal to 5 mm. Wherein the nitrogen-oxygen sensing device comprises a nitrogen-oxygen sensor and a plurality of gas circulating pipes, the plurality of gas circulating pipes are fixedly connected with the inner wall of the post-treatment gas outlet pipe, the extending direction is along the radial direction of the post-treatment gas outlet pipe, the gas inlet side of each gas circulating pipe is provided with a gas inlet hole, and the gas outlet side of each gas circulating pipe is provided with a gas outlet hole. The perforated plate comprises a through hole in the gas circulation direction of the post-treatment gas outlet pipe, and the through hole is used for allowing gas exhausted from the nitrogen-oxygen sensing device to pass through, so that the gas exhausted from the nitrogen-oxygen sensing device is decelerated through the perforated plate, Karman vortexes behind the nitrogen-oxygen sensing device are shielded, high-frequency noise in exhaust noise is reduced, and the comfort of the whole vehicle is improved.

An expansion valve comprises a valve seat and a valve needle, the valve seat is provided with a valve cavity and a valve port channel, and the valve needle comprises a tip part and a columnar part; the valve port channel comprises a first valve port channel and a second valve port channel, and the second valve port channel is far away from the columnar part relative to the first valve port channel in the height direction of the expansion valve; a first opening is formed in the end, close to the columnar part, of the first valve port channel. A second opening is formed in the end, close to the first valve port channel, of the second valve port channel. A plane perpendicular to the height direction of the expansion valve is defined as a first projection plane, the orthographic projection of the inner wall corresponding to the first opening on the first projection plane is a first projection, the orthographic projection of the inner wall corresponding to the second opening on the first projection plane is a second projection, and at least part of the second projection is located in the first projection; the area enclosed by the first projection is larger than the area enclosed by the second projection.

The utility model discloses a compressor and refrigeration equipment, the compressor comprises a compressor shell, a support and a liquid storage device, the compressor shell comprises a first main shell and a first upper shell installed at the upper end of the first main shell; the bracket is connected with the outer wall of the first main shell; the liquid storage device is arranged on the peripheral side of the compressor shell and connected with the support, the liquid storage device comprises a second main shell and a partition plate, the partition plate is arranged in the second main shell and fixedly connected with the inner wall of the second main shell, and the partition plate is located between the plane where the upper end face of the support is located and the plane where the lower end face of the support is located; in the height direction of the first main shell, the minimum distance between the upper end face of the support and the upper end face of the first main shell is H1, and the requirement that H1 is larger than or equal to 10 mm and smaller than or equal to 20 mm is met. According to the compressor, the inherent frequency of the liquid storage device can be improved, high-frequency resonance between the liquid storage device and the pump body assembly of the compressor is effectively reduced, and therefore high-frequency noise generated in the operation process of the compressor is reduced.

The invention discloses an exhaust silencer with a self-adaptive adjusting valve. The exhaust silencer comprises a first exhaust pipe and an adjusting valve assembly. Channels extending from the air outlet end to the air inlet end of the first exhaust pipe in the extending direction of the first exhaust pipe are formed in the opposite positions of the pipe wall of the first exhaust pipe, and a plurality of through silencing holes are formed in the pipe wall of the first exhaust pipe in the circumferential direction and the extending direction of the first exhaust pipe; the adjusting valve assembly comprises a fixing base, two elastic pieces and a valve plate. The fixed seat is fixedly connected to the outer wall of the first exhaust pipe; the valve plate comprises a baffle plate and at least two connecting strips; the blocking piece is vertically arranged and slidably connected into the first exhaust pipe. The first ends of the two connecting strips are fixedly connected to the opposite positions of the edge of the blocking piece correspondingly, and the two connecting strips are slidably connected in the two channels correspondingly. The first ends of the two elastic pieces are connected with the second ends of the two connecting strips respectively, and the second ends of the two elastic pieces are connected with the fixing base. Corresponding to different application working conditions, the position of the valve plate can be adjusted in a self-adaptive mode, and the noise reduction performance is improved under the condition that smooth tail gas circulation is guaranteed.

This application provides a single-sided detection system and vehicle. The single-sided detection system includes a voltage divider circuit, an amplifier circuit, an isolation circuit, an output circuit, and a controller. The voltage divider circuit divides the voltage of the high-voltage DC bus to obtain a first output voltage. The amplifier circuit is connected to the voltage divider circuit. The isolation circuit is connected to both the amplifier circuit and the voltage divider circuit. The output circuit includes a first operational amplifier and a first resistor. The inverting input terminal of the first operational amplifier and one end of the first resistor are connected to the fifth terminal of the isolation circuit, and the non-inverting input terminal of the first operational amplifier is connected to the sixth terminal of the isolation circuit. The first operational amplifier generates a second output voltage. The controller determines the voltage of the high-voltage DC bus based on the second output voltage. This single-sided detection system can isolate and monitor the voltage of the high-voltage DC bus, promptly detect voltage anomalies, and, with the isolation circuit, provides a high level of overall system safety.

The utility model provides a direct-current step-down power supply circuit and an energy storage air conditioner. The direct-current step-down power supply circuit is used for an energy storage air conditioner and comprises a step-down conversion module which is connected with direct current through the input end of the step-down conversion module and carries out voltage conversion on the direct current; the enabling module comprises a first resistor and a second resistor, the first end of the first resistor is connected with the enabling end of the step-down conversion module, the first end of the second resistor is grounded, and the second end of the first resistor and the second end of the second resistor are jointly connected to the enabling end of the power supply chip; the first resistor and the second resistor are used for calculating the range of the input voltage of the step-down conversion module so as to drive the step-down conversion module to work according to the input voltage of the step-down conversion module; and the output processing module is used for filtering high-frequency noise and harmonic waves in the voltage of the output end of the step-down conversion module. According to the circuit, through the enabling module, the step-down conversion module can be effectively protected according to the input voltage range, and the requirement of an energy storage air conditioner can be met.

The utility model belongs to noise reduction device technical field especially has a packing noise reduction device with air outlet buffer structure, including electromagnetic valve and frame board, the outside of electromagnetic valve is equipped with frame board, the inside of frame board has established screw groove and storage groove in proper order, storage groove and connecting plate sliding butt joint, the upper side of connecting plate is connected with the one end of bolt through bearing. This packing noise reduction device with air outlet buffer structure, when electromagnetic valve starts, gas passes the air outlet hole of electromagnetic valve and enters the inside of connecting pipe, the elasticity of connecting pipe can absorb and weaken the vibration between airflow and pipe wall, and the vibration and the propagation of sound that isolation layer can reduce the vibration of connecting pipe, after the air diffusion and flow in the open hole box, can effectively reduce the impact sound and high frequency noise of airflow, make packing noise reduction device in long -term operation, especially in the system of frequent switch can stably carry out noise reduction to electromagnetic valve.

This application discloses an effective signal extraction method and system based on CVAE, relating to the field of digital signal processing. The specific steps are as follows: constructing a conditional variational autoencoder (CVAE), which includes an encoder, a reparameterization module, and a decoder; constructing a training dataset based on an observation dataset and a corresponding set of conditional variables; training the CVAE using the training dataset and optimizing its parameters using a loss function based on physical consistency constraints; the loss function based on physical consistency constraints includes a reconstruction error term, a KL divergence loss term, and a physical constraint loss term; obtaining the data to be processed and the corresponding conditional variables; and inputting the data to be processed and the conditional variables into the trained CVAE to obtain the effective signal. This application introduces physical consistency constraints through a CVAE, effectively reducing high-frequency noise and pseudo-frequency components, making the reconstructed signal closer to the real signal.

The utility model discloses a pump body assembly, compressor and refrigeration equipment, the pump body assembly comprises an air cylinder, a first bearing and a second bearing, the air cylinder is provided with a third through hole, and the third through hole penetrates through the end faces of the two sides of the air cylinder; the first bearing is installed on one side of the air cylinder and provided with a first through hole and a first resonant cavity, the first through hole penetrates through the end faces of the two sides of the first bearing, and the first resonant cavity is located on the end face, facing the air cylinder, of the first bearing and communicates with the first through hole. The second bearing is installed on the other side of the air cylinder and provided with a second through hole, the second through hole penetrates through the end faces of the two sides of the second bearing, and the second through hole, the third through hole and the first through hole are sequentially communicated to form an exhaust channel; the volume V1 of the first resonant cavity and the volume V2 of the first through hole meet the condition that V1 / V2 is larger than or equal to 0.2 and smaller than or equal to 0.6. The pump body assembly is good in noise reduction effect and high in structural strength.

The utility model relates to the technical field of air conditioners, in particular to an axial flow fan which comprises an installation disc, blades, a first reinforcing part and a second reinforcing part. The blades are arranged on the peripheral wall of the mounting disc; the first reinforcing part is arranged on the suction surface of the blade and is close to the front edge side of the blade; the first reinforcing part extends to the blade top of the blade from the blade root of the blade; the second reinforcing part is arranged on the suction surface of the blade and is close to the tail edge side of the blade; the second reinforcing part extends to the blade top of the blade from the blade root of the blade; the structural strength of the blades is improved, and therefore the strength requirement of the axial flow fan is met.

The present application relates to the technical field of safety protection tools, and is especially a pumped storage power station active noise reduction safety protection device and a noise reduction method, comprising a wearable shell and an active noise reduction mechanism, the inner wall of the wearable shell is provided with sound-absorbing cotton, and an inner lining frame is fixedly arranged on the inner side of the sound-absorbing cotton, the active noise reduction mechanism comprises a sound pickup end, a loudspeaker end and an active noise reduction unit, and the inner walls on the left and right sides of the wearable shell are both provided with jacks. The present application combines passive noise reduction with active noise reduction, first uses the selective noise reduction characteristics of sound-absorbing cotton to reduce high-frequency noise, uses polyester fiber sound-absorbing cotton for sound insulation in the wearable shell to reduce high-frequency noise, and then embeds a low-pass filter in the active noise reduction protection device to filter high-frequency noise again, ensures that the ANC master control module focuses more on the processing of low-frequency noise, and guarantees the low-frequency noise reduction effect.

The utility model relates to the technical field of stamping dies, in particular to a noise reduction type automobile stamping die and a control method.The noise reduction type automobile stamping die comprises a base, a die table is fixedly installed above the base, a die groove is formed in the upper end of the die table, a channel is formed in the lower end of the die table, and first air cylinders symmetrically distributed along the base are arranged in the channel; the lower end of the first air cylinder is fixed to the surface of the base through a screw, and a first piston rod for stretching is arranged in the first air cylinder. According to the scheme, wide-frequency-band noise control is achieved through the design of the five-layer composite sound insulation cover, the core innovation is that the synergistic effect of the array type rubber sound insulation columns and layered materials is achieved, the hollow structures of the sound insulation columns are combined with the rubber damping characteristic, 500-2000 Hz high-frequency noise can be attenuated in a targeted mode, and the impedance gradient design of the polyurethane foam reinforcing layer and the sound insulation cotton layer can achieve the purpose of noise reduction. And the die adopts a two-way limiting mechanism and a double-cylinder driving design, so that the accurate matching of a die head and a die groove is ensured, and the repeated positioning accuracy of stamping is high.