| dc.description.abstract | For a low-pollution required machining process, the Micro-Volume-Machining without cooling liquid is a new trend. Designing an appropriate fixture and tool system based on workpiece geometry characteristics and machining precision is called Micro-volume-machining system. For achieving above objection, the system needs to be devided into fixture subsystem and tool subsystem. Initially, reaching submicrometer is the first goal in the research of fixture design. And, the tool system needs to be studied based on machining characteristics.
To perform miniature shape or form machining instead of precise positioning only, the degree of freedom of flexure must be greater than 3. The hybrid machining, such as mill-polishing, must gratify the same requirements either. The need of more intricate functions means not only a more elaborate monolithic and compliant mechanism but more easily made are compulsory. Accordingly, this paper presents an elastic-plastic flexure hinge mechanism (EPFHM) for precisely generating a muliti-axis micro-motion, which is made by elastic-plastic flexure hinge stage (EPFHS) and piezoelectric actuator (PZT). After the appropriate analysis of the system, the device is designed to meet with the prerequisites of flexure hinge mechanism. As long as the certain fulfilled design parameters under the condition of the purposed criteria, the results of experiment reveal that the stiffness is quasi-linear even with the application of elastic-plastic material and the micro-moving is generated in accordance with the anticipated demand. Micro-milling experiment with X-Y-A-B flexure fixture results concealed that the surface roughness is approxing to Ra 0.4 .
A new mathematical model for cutting tool is developed using angle-solid-block approach to find the relationship of design parameters. The design parameters around cutter tip need to be defined as dependent relationship one another in order that the uncertainty of chisel edge and main cutting edge determined by existed model can be avoided. The effects of the new mathematical model on the geometry of chisel edge and main cutting edge are shown in this paper. In addition, the extensive study presents a new approach to design a form milling cutter for precisely obtaining the complex free-form surfaces. In this study, the intersection point of rake surface, helix flute and clearance flank is appropriately defined due to its significant role in the design and grinding performance. The angle-solid-block analysis is developed to establish the solid geometry model of new form milling cutter. Hence, a new form milling cutter satisfying the requirements of machining characteristics of workpiece can be designed. In addition, the cutter geometric model can be adopted to map out the measuring strategy with minimum measured points to attain the exact geometric feature of cutter. | en_US |