Rotary table with frameless motor

摘要

A rotary table for a material processing machine such as a vertical milling machine utilizes direct drive motor(s) to precisely angularly position a work piece along one or more pivotal axes. The direct drive motor(s) are thermally insulated from the remainder of the machine to limit misaligning thermal expansion of the components of the machine. The motors may be symmetrically attached to their respective supports such that thermal expansion/contraction of the motor and surrounding components occurs symmetrically with respect to the motor to limit misalignment of the motor's rotational axis. A motor may mount to its respective support only at a first axial end thereof such that thermal expansion of a second axial end of the motor does not adversely shift the position of the first end. Axially narrow clamps selectively secure the rotors of the motors in desired positions.