Mechnical Design Systems Laboratory, Hiroshima University

To drastically enhance the material removal efficiency of a machine tool, this paper proposes a completely new machine tool configuration with multiple spindles. Conventional machine tools with multiple spindles have separate workspace for each spindle, and thus cannot simultaneously machine a single workpiece by multiple spindles. Conventional multi-spindle machine tools are typically used to separately machine different workpieces independently by each spindle. To simultaneously machine a single workpiece by multiple spindles, without a risk for each spindle to interfere with each other, this paper proposes a machine tool configuration with three spindles, each of which is driven by a linear axis parallel to each other (X1-, X2- and X3-axes), and a vertical Z-axis (Z1-, Z2-, and Z3-axes). The work table is rotated by a rotary axis (C-axis). This paper presents an algorithm to generate command trajectories for this machine configuration. The machining simulation is presented to show that arbitrary 3D geometry can be machined simultaneously by three spindles, and thus the machining time can be significantly reduced compared to a conventional machine configuration with a single spindle. Potential issues with the proposed configuration will be also discussed.

Keywords: Machining, machine tool, multiple spindles, efficiency