Papers by Keyword: Surface Grinding Machine

Abstract: In order to realize environmental-friendly machine tools, a linear-motor-driven table supported by constant-flow hydrostatic water bearings is developed. The table system is free from environmental pollution because the system needs no oil. For simplicity, a single-sided bearing system is chosen for the table-slide. To obtain a high sustaining force, preload is applied to the bearings using the attractive force of an iron core linear-motor’s magnets. The preload is effective in both the vertical and horizontal directions by inclined motor magnets. Miniature gear-pumps supply flow to the bearings without pump pulsation, and the bearings consume very small amounts of water and electric power. The measured table sustaining force was 3.0kN and static stiffness was 0.3kN/m under a flow rate Q=0.92mL/s per bearing and ideal bearing clearance h=16m.

Abstract: In order to improve the machining accuracy of the precision surface grinding machine, a 3-DOF micropositioning table is used as an auxiliary table to form the dual infeed system with nanometer level positioning accuracy. This paper mainly deals with the static characteristics of the micropositioning table. The direct and inverse kinematic models are obtained under different orientation descriptions, and the inherent relationship between different orientation descriptions is investigated. By use of Eular angle description, the reachable orientation space of the micro-positioning table is obtained. The theoretical static stiffness on the top surface of the table is also given, and the experimental tests are carried out to verify the established models.

Abstract: In order to eliminate unnecessary table-over-travel of a surface grinding machine, the authors previously developed an adaptive table-reciprocation-control system using a hydrophone. The system eliminated the over-travel and reduced grinding time by 20-40%. However, during the stage of the grinding-wheel approach to a workpiece the system did not work. In order to improve the efficiency and reliability of the system, a fluid-flow stabilizer and a new coolant-supply nozzle have been developed and their performances were experimentally investigated. By using these devices, the reciprocation-control system showed its capability even during the stage of the grinding-wheel approach and this ability improved the system efficiency and reliability.