The Stiffness Study Of Crankshaft External Circular Complex Cutter Institutions

The crankshaft external circular composite turning machine tools is a follow-up turning machine, it can realize the main journal of crankshaft'and connecting the neck'all the processing after the workpiece's loading. A parallelogram cutter institutions is the core of crankshaft processing composite lathe machining,and can bear a wide load in the processing of cutting. The cutting stiffness of cutting institutions directly determines the lathe machining's accuracy and cutting efficiency. Therefore, this paper is mainly based on the stiffness study of cutting institution in cutting, to analyze its influencing factor and to put forward the improvement measures in realation to the stiffness of cutter institutions, so as to realize the crankshaft high speed, efficient, high precision machining and ensure a higher productivity, providing a practical solution.Considering the cutter institutions must realize the follow-up turning, you must request cutter organization structure meet:cutter crank length should be equal to the length of the crank of the processed the crankshaft;cutter crank movement is in consistent with the workpiece phase. Then,the major parts of cutter institutions is made with designing and checking, such as axis, crank dish locked structure and the design of cutting crank. Finally, the design of cutter organization has been completed and cutter institutions of assembly body model 3d has been modeled.Using ANSYS software proceeds the static analysis of the stiffness of cutting of respectively from the cutter connecting rod materials, cutter institutions two unequal crank, bearing stiffness. The results show that the stiffness and strength of the aluminum material cutting connecting rod connecting has decreased slightly in comparision to the steel materials, but its quality and inertia has greatly decreased, so we can consider the materials of cutter connecting rod for aluminum materials besides the installing part;the cutter crank unequal makes the stiffness of cutter connecting rod mechanism decrease, so we must adjust carefully two crank length and ensure cutting length equal; the stiffness of cutter connecting mechanism rod increases with the increase of bearing stiffness, so control bearing stiffness is of great significance for improving the stiffness of cutter connecting rod mechanism and cutting performance of the whole cutter agencies. Finally, the cutter institutions assembly body has been analyzed, and the result shows that the cutting institutions's deformation is small.its static stiffness is satisfied with the requirement, and it provide the basis for putting forward improving measurement for positions of the local deformation big.Using finite element analysis software ANSYS analyzes the dynamic stiffness of cutter connecting rod and cutter crank, and the results show that the stiffness of cutting institution greatly improve in the bearing preloaded force function.And confirm each bearing preloaded force by combining the matching principle of cutting stiffness. Finally, we analyze cutting institutions existing problems from the adjustment of cutting crank length, bearing preloaded force's determination, the transmission mechanism and the counterweight plate, and puts forward the feasible method and improved structure diagram.