A STUDY ON INTEGRATED OPTIMAL DESIGN FOR A HIGH-PRECISION INTERNAL GRINDER
Hu Rufu Sun Qinghong Chen Nan (Dept. of Mechanisc Southeast University, Nanjing, 210096 ) (Ningbo College )
Dynamic optimization design is the key to improve the machining precision of machine tools. The structural deficiencies of the internal grinder was pointed out by analyzing its FE model. A method of frequency correction was proposed, by which the mold frequencies of the main parts of the internal grinder were disclosed, and increase in vibration of the internal grinder avoided when the prompting frequency of the internal grinder comes close to its nature frequency. In addition, the value of relative vibration between the cutting tool and work piece in its first natural frequency was considered as a standard of estimation of the machining precision for internal grinders, the model force method was applied to seek the structural weakness of the internal grinder in order to achieve dynamic optimization of the parts. The results of both methods applied in the integrated optimal design of the internal grinder show that the first stage natural frequency of the re designed internal grinder is increased 17% compared with the original, the vibration mode relative displacement between the head of grinder and work piece is reduced 10%, and the response displacements of the first and second stage natural frequency in the head of the grinder is reduced 28% and 41%.