Research On Structural Noise Reduction And Vibration Noise Control Of Particle Vibration Rehabilitation Device

Modern medical research has found that it has a positive effect on human body to apply appropriate mechanical vibration,such as easing muscle fatigue and tension,promoting blood circulation and accelerating postoperative nerve desensition.The previous generation prototype developed by our research and development has realized the control of particle flow direction and vibration intensity in principle,but there is the problem of excessive structural noise caused by mechanical vibration.Unable to meet the requirements of medical places,the vibration and noise control of particle vibration rehabilitation instrument is studied in this paper.The main work is as follows:1?In this paper,noise source identification,frequency spectrum analysis,vibration response analysis and modal analysis were performed using distributed operation method,near-field sound intensity test,noise level evaluation test at site,vibration strength test,vibration response test and modal test.Cylindrical drum is the main noise source and there is double frequency noise caused by the collision between the large cylindrical drum and the floor.The noise is dominated by medium and low frequencies.2?Simulation method of combining the use of test and calculation,established the prototype model is simplified,and the simplified model for the finite element calculation of pretreatment,the finite element analysis,the vibration response and acoustic calculation,calculation data and test data comparison,the rationality of the established model was verified,and provide the basis for structure optimization model.3?Proposed improve rigidity and vibration isolation,reduce the vibration transmission,avoid collision frequency multiplication noise,selection with damping material features,the optimized plan for the cylinder barrel and on the basis of optimized scheme barrel height and wall thickness of different material sites based on the structure of the calculation of modal noise transfer function,select the optimal parameter combination plan processing testing,validation testing.According to the experiment,the sound pressure level at the field point is reduced by 15dB(A),and the main noise is derived from the cylinder.4?The sound cover is designed to further reduce the noise level of the prototype.The sound cover and soundproof materials of the inner wall of the enclosure and the barrel are systematically studied and analyzed,the radiation noise is further reduced,the noise control is performed,the assembly and processing are completed,and the noise reduction effect is verified through experiments.The results show that the sound pressure level at the field point is 10.3dB(A).