Localization Liquid Mixer Vibration System Study Design And Simulation Analysis

Instead of import,domestic manufacture of the complete Eppendorf Thermo-mixer5355 is required.According to the researches,the vibration system is the key for well liquid mixing.The eccentric force generated by the motor is applied on the elastic plastic beam,while the eccentric mass drives the vibrating platform to reciprocate and vibrate in X and Y directions alternatively,thus to mix the liquid well in the test tube.The heat treatment process for the plastic beam is complicated,hence,for the newly designed vibration system the metal elastic materials are used as substitutes.In addition,researches on the original vibration system and analysis on vibration simulation of the new system have been conducted,and the comparison analysis based on the sample machine of the new system has been performed.It is required that the liquid mixing effect and vibrating parameters of the new system shall be equal to or in a higher level than those of the imported vibration system.Firstly,mixing tests have been conducted on the 5355 original system under different conditions with different liquid samples of different volumes and at different motor speeds,and tests results have been obtained.According to the results analysis,the liquid volume(i.e.the vibrating loads)and the motor speed(i.e.the vibrating frequency)have significant influence on the mixing effect.Secondly,vibration characteristics testing system for the5355 mixer has been built,and according to the data analysis,the vibration displacement is in direct proportion to the vibrating loads.Vibration of the identification system belongs to the harmonic steady-state forced vibration,and the system is under the influence of inertia.The new vibration system is designed to adopt the configuration of combining the elastic steel slice with the vibrating blocks in the X and Y directions.Considering the difficulty to measure the rigidity of the POM elastic beam and the influence imposed by the vibrating loads,different steel slices with different thicknesses and eccentric mass differing from that of the system are selected.In ADAMS,vibration simulation of the rigid-flexible coupling model with the elastic steel slice as the flexible body and the vibrating blocks as the rigid body is conducted.Through orthogonal experimental design and comprehensive balance method,the new vibration system is obtained.Vibration simulation analysis and comparison have been conducted,and according to the analysis,the vibration characteristics of the new system are generally the same as those of thevibration system of the original imported mixer.The inherent frequency for the new vibration system is calculated based on vibrational science.Modal analysis is made with the ANSYS,and the modal characteristics and inherent frequency are obtained;besides,system frequency ratio is calculated,and amplitude-frequency response curve is obtained.All the above prove that no resonance risks exist in the system.Finally,based on the above analysis,the new vibration system is produced,and tests and analysis on the mixing effect and the vibration characteristics have been performed.According to the results,the mixing effect of the new vibration system is much better than that of the vibration system of the original imported mixer,and the loads capacity has been expanded.Under the high-frequency vibration,the load capacity has been raised from 2 ml to 50 ml.Correctness of the rigid-flexible coupling model and simulation data has been verified,and the objective of domestic manufacture of new vibration system is realized.