Influencia del comportamiento de una máquina de cinemática paralela en los procesos de micromecanizado de filo único

Abstract

Abstract: This thesis presents a novel micro-machining process in which a single-edge tool is able to cut chip sections of a micrometric range with a proper chip formation. The basis of this process consists in the translation and orientation of the cutting tool tangent to its trajectory. To achieve this goal an innovative 6 degrees of freedom parallel machine-tool, with high stiffness and enough positioning precision of the tool-tip was developed. The built machine is based on a hybrid device composed by a 3PRS (prismatic-revolution-spherical) parallel mechanism with a linear XY-Stage and a C rotational axis. A cutting model has been established that considers all the angles of the process to determine the load to which the machine will be subjected and thus establishing its deformation. To manufacture a workpiece properly, a machining strategy has been developed considering the geometry of the tool and the kinematic restrictions of the machine-tool. Through the kinematic and dynamic modelling of the machine, it is possible to establish the level of work precision for a given machining strategy. From the tests carried out, it is shown that the proposed parallel machine tool-process is an alternative to micro-milling technologies. A large number of experimental tests have been made under several manufacturing conditions in which the machine tool operates. It is concluded that the proposed cutting model in the hybrid machine tool is a precise and competitive alternative to the actual manufacturing technologies.