An uncertainty analysis of tool setting methods for a precision lathe with a B-axis rotary table

摘要

This study develops a method for calculating the precision with which a cutting tool can be set along the axis of rotation of a B-axis rotary table on a lathe. The uncertainty with which the tool can be set on the rotary table is calculated from knowledge of the machine tool, the probing system, and the effects of the environment. Three common tool-setting techniques are analyzed as examples. The techniques analyzed are a touch probe tool set station, a technique that machines grooves in the face of a workpiece and then measures the relative depths of the grooves, and an optical tool set station that uses a video camera looking down onto the rake face of the cutting tool. Experiments using these three example techniques reveal the precision with which a tool can be set. For each technique, the predicted tool setting uncertainties agree with the experimentally determined values. Therefore, this method can estimate how well a tool can be set along the axis of rotation of a B-axis rotary table for a particular application, without the need for extensive tool setting experiments.