| Linear compressor has the advantages of energy saving and high reliability.It is the development direction of compressor technology.With the in-depth study of linear compressor,the plate spring support technology has become one of the key technologies of linear compressor,and the application of plate spring has played a huge advantage in improving the working efficiency and operating life of linear compressor.Most of the existing plate springs are three-arm vortex flexible plate springs,which have large radial stiffness but small axial stiffness.In practical application,multiple plate springs are needed to be used superimposed,which increases the overall size and manufacturing cost of the linear compressor,and affects its commercial value and market competitiveness.In order to meet the requirements of axial stiffness and miniaturization of linear compressor,it is necessary to further study the structure of spring used in linear compressor and the performance of spring assembly.The main research contents of this paper are as follows:(1)In order to solve the problem of low axial stiffness of traditional plate spring,a new type of coil spring for linear compressor was designed,and the design method of the center profile of the coil spring is presented.The central profile parameters of the coil spring arm were optimized by response surface optimization method.The results showed that the axial stiffness of the coil spring was increased by 42.5%,and the radial stiffness was increased by 26.8%.(2)The number of arms of the coil spring was optimized.The stiffness and maximum stress of eight different arm springs were analyzed and compared by using the finite element analysis method,and the stiffness and fatigue strength characteristics of the coil spring and the flexible plate spring were analyzed and compared.The results show that the axial stiffness of the coil spring is better than that of the flexible plate spring,and the radial stiffness of the flexible plate spring is better than that of the flexible plate spring.Under the same axial stiffness,the fatigue strength of the coil spring is better than that of the flexible plate spring.(3)The mathematical model of the mechanical system of the linear compressor was established.According to the relevant parameters of the linear compressor,the stiffness requirements of the spring group were calculated,and two spring groups were designed.The first scheme used8 plate springs,and the second scheme used two plate springs and a coil spring.By analyzing the axial stiffness and radial stiffness of spring groups of the two schemes,it is found that the axial stiffness of the two schemes both meet the design requirements.The radial support effect of the first scheme is better than that of the second scheme,but the second scheme saves more material and production cost.(4)simulation studies the arrangement way and spring spring component spacing effect the performance of the spring group support,it is concluded that the optimal way of arrangement and spring set spacing,and analyzes the spring set gravity caused by the piston radial piston system migration,the modal analysis to extract the spring set of the piston top six modes,and through the transient dynamic analysis method,studied in 30Hz～70Hz 5 groups within the scope of the spring set of piston system dynamic performance under different frequency.(5)The axial stiffness of the coil spring and plate spring,as well as the axial and radial stiffness of the spring group were tested experimentally,and the experimental results were compared and analyzed with the finite element analysis results.The resonant frequency of linear compressor with air as compression medium is tested by experimental test platform.The thesis has 73 figures,13 tables and 90 references. |
PDF Full Text Request