| With the continuous increase in the number of elevators in villas and other private houses in China,the ride comfort is getting more and more attention,and the vibration of the elevator system is the main factor affecting the ride experience.This thesis is based on the project between Jilin University and Hangzhou Jiepai Transmission Technology.In view of the fact that a certain type of home light forced drum elevator and its supporting reel and other devices could cause abnormal vibration of the elevator system during field measurement in a general elevator shaft.It is necessary to analyze the vibration of its elevator drive host system and put forward corresponding improvement measures.At present,most of the domestic and foreign studies on the vibration of elevator systems focus on high-speed traction elevators used in high-rise buildings.However,home light forced drum elevators generally have low vibration levels,so few studies have been conducted.At the same time,most studies have performed simulation analysis on the inherent characteristics and dynamic performance of elevator systems by establishing Matlab simulation programs.Compared with the finite element analysis method,it is difficult to clearly observe the deformation of each part of the system at different frequency values.At the same time,most studies have established vertical or horizontal vibration models of elevator systems separately,ignoring the effect of interaction between vertical and horizontal vibrations on system vibrations.The vibration of the elevator system cannot be optimized by relying only on the natural frequency of the unidirectional vibration model.Therefore,it is necessary to use the finite element method to analyze the overall vibration of the home light forced drum elevators system.The main research contents and related conclusions are as follows.(1)Parametric model of main components is built according to the transmission principle of an elevator drive host system.Based on this,a finite element model of the elevator drive host system is established.The contact relationship between each part is established,the material properties are added,and the meshing is completed.Next,the theory of modal analysis and frequency response analysis is derived.Based on the finite element method,Lanczos algorithm and modal superposition method are used to perform modal analysis and frequency response analysis of the elevator system.The first six natural frequencies and natural modes of the system are obtained,as well as the acceleration response of the system at different frequencies.It is concluded that the first natural frequency of the system and the motor excitation less than the frequency are likely to be the causes of resonance.(2)Through the bench test and field test,the vibration acceleration of servo motor,reducer box and cabin interior are measured respectively.Next,the root mean square value of acceleration was calculated.Meanwhile,the effect of coupling on the vibration acceleration of servo motor and reducer in bench test is studied.Then,the measured time-domain data are transformed by fast Fourier transform to obtain the corresponding frequency-domain curve.In the frequency-domain analysis,firstly,the correlation between the peak frequency of acceleration and the rotation frequency of the motor is explored.Secondly,the test results are compared with the simulation results to ensure that the peak frequency of vibration during the operation of the elevator drive host system is greater than the natural frequency of the system.Combined with the above two conclusions,it is verified that the resonance phenomenon does exist in the working process of the system.(3)Based on the stiffness and strength analysis results of the reducer box,use SIMP topology optimization method to optimize its structure and redesign the box structure based on the topology optimization.Under the premise of meeting the requirements of strength and rigidity,the weight of the reducer box has been reduced by 15.4%.Furthermore,a finite element model of the elevator drive host system after the weight reduction of the reducer box is established,and modal analysis is performed to ensure that the low-order natural frequency of the system does not decrease significantly and the vibration level does not increase significantly.Finally,measures to change the structure of the support and the stiffness of the wire rope are proposed to suppress the system vibration.The modal analysis method was used to verify the above vibration reduction measures.After the optimization,the first-order natural frequency of the system was increased by 14.7% and 23.2% respectively compared with the original scheme,which can significantly reduce the system vibration level.And provide a reference for the design and damping of home light elevators. |
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