7 results about "Vibration transmissibility" patented technology

This invention relates to a full-frequency vibration reduction design method for metamaterial pipelines based on multiple band gaps, comprising: establishing an equivalent mechanical model of the target pipeline; periodically arranging elastic supports on the target pipeline to induce the formation of a zero-frequency band gap and a Bragg band gap, coupling the equivalent support stiffness of the elastic supports with the equivalent mechanical model of the pipeline to construct a first band gap calculation model; periodically arranging local resonant vibration absorbers on the target pipeline to form a local resonant band gap, coupling the equivalent stiffness and equivalent mass of the local resonant vibration absorbers into the first band gap calculation model to obtain a second band gap calculation model; constructing a system finite structure dynamic vibration calculation model with a second assembly as the analysis object; constructing a vibration transmissibility index, and using the system finite structure dynamic vibration calculation model as a fitness evaluation tool for a genetic algorithm to perform non-periodic optimization of the elastic support positions, solving for the optimal arrangement position of the elastic supports with the largest bandwidth of the zero-frequency band gap.

The application provides a shell radiation noise evaluation method and device and electronic equipment. The method comprises the following steps: obtaining a modal vibration mode of a shell structure; determining a plurality of measurement points of the shell structure based on a modal vibration region of the modal vibration mode; determining vibration transmissibility data of each measurement point through a vibration sensor when each measurement point is tapped; determining vibration overall radiation energy of the shell structure based on the vibration transmissibility data of the plurality of measurement points, and determining shell radiation noise of the shell structure based on the vibration overall radiation energy. In this way, the shell radiation noise level in the actual operation process of the shell structure can be effectively predicted by carrying out tapping test on the measurement points of different parts of the shell structure to obtain the vibration transmissibility data without running test on the electric drive bench, so that the NVH performance of the electric drive product and the comfort of the new energy vehicle are improved.

This utility model discloses a vibration-damping and noise-reducing silent heat sink, including a heat sink assembly, a fan, and a base plate. It also includes a vibration-damping connector and a flow guide shroud. The vibration-damping connector is made of an elastic material and has a ring-shaped structure, nested between the fan and the flow guide shroud. The flow guide shroud surrounds the air outlet side of the fan, and its inner wall has a spiral flow guide groove. The heat sink assembly includes multiple wavy, non-equidistantly arranged heat dissipation fins, forming a gradually expanding airflow channel. The bottom of the base plate has a honeycomb-shaped vibration-damping cavity filled with damping adhesive. The three-stage vibration-damping structure significantly reduces vibration transmission rate, reduces resonance, and extends equipment life. The spiral flow guide groove, sound-absorbing grille, and wavy fin phase difference design significantly reduce wind noise and structural noise.

The present application belongs to the technical field of air suspension, and provides a vehicle air suspension damping effect determination method, system and application, comprising synchronously acquiring input acceleration and output acceleration of a vehicle air suspension under simulated road excitation; based on the input acceleration and the output acceleration, calculating a vibration transmission rate and performing frequency domain analysis to obtain a frequency domain transmission rate curve representing the damping effect of the air suspension; based on the frequency domain transmission rate curve, establishing a quantitative criterion for guiding design, the quantitative criterion comprising full-working-condition adaptability, parameter correlation and performance consistency; based on a quantitative mapping relationship between key parameters of the air suspension and a change amount of the vibration transmission rate at a characteristic frequency constructed according to the parameter correlation quantitative criterion, an optimization strategy of the key parameters of the air suspension is determined with the vibration transmission rate of a target frequency band as the optimization direction. The present application can accurately evaluate the energy filtering efficiency between road input and vehicle body response of the air suspension.

This invention relates to the field of diesel generators, and in particular to a quiet diesel generator, comprising a chassis unit, a power generation unit mounted on the chassis unit, a sound-absorbing unit mounted on the chassis unit, and a docking unit between the chassis unit and the power generation unit. This invention forms a double-layer common chassis by placing a wire rope vibration isolator and an air spring between the upper and lower base layers, reducing the vibration transmission rate of the diesel generator to the ground during operation and blocking the propagation of engine vibration to the foundation and building structure. Simultaneously, through the installation of a closed enclosure and a hollow layer, an integrated sound-absorbing and sound-insulating cavity is created outside the generator and diesel engine, reducing the noise transmitted by the diesel generator to the outside, enabling the equipment to meet the usage requirements of noise-sensitive areas such as hospitals and residences. This invention also utilizes the fault tolerance capability of the worm gear and gear-driven generator coupling assembly to achieve rapid alignment and periodic adjustment of the generator and diesel engine.

The present application relates to the field of textile machinery and damping control, specifically to a warp knitting machine high-stability bearing seat and a method thereof; comprising a bearing main frame, a damping energy dissipation core, a leveling support foot, a spherical self-adaptive pad, a monitoring part and a controller; the system obtains top and bottom end vibration data in real time through a sensor, calculates vibration transmission rate and attenuation rate and then solves dynamic stiffness, thereby evaluating damping aging state and calculating resonance critical speed; the core is to densely fill the damping energy dissipation core in the main frame to dissipate periodic excitation energy generated by high-speed operation, and to use spherical contact matching of the hemispherical protrusion at the bottom of the support foot and the hemispherical groove of the spherical self-adaptive pad, so that the support foot can be freely deflected to adaptively compensate uneven ground; the present application solves the problems of insufficient existing foundation stiffness and obvious high-frequency vibration transmission, effectively avoids long-term stress concentration and loose connection of the rack, and greatly improves the support stability.

This invention relates to a method and system for testing the vibration isolation performance of a brake vacuum tube. The testing method involves setting an excitation point and a response point on the brake vacuum tube under test; applying excitation to the excitation point and obtaining the transfer function of the response point; and obtaining the comprehensive vibration transmissibility of the brake vacuum tube under test based on the transfer function, thereby determining the comprehensive vibration isolation performance of the brake vacuum tube. This invention also provides a testing system for the vibration isolation performance of a brake vacuum tube, including a testing platform, a first support and a second support thereon, a first slide rail on the first support, and a second slide rail on the second support; sensors are arranged at both ends of the brake vacuum tube under test, the sensors are connected to a data acquisition terminal, the data acquisition terminal is connected to a computer, and the data acquisition terminal is also connected to a hammer. By applying excitation to the brake vacuum tube under test, the corresponding transfer function is obtained. This invention can accurately evaluate the vibration isolation performance of brake vacuum tubes and provides a reliable reference for the design improvement of brake vacuum tubes.