AUTOMATIC SURFACE TRACER

摘要

A device for tracing a surface such as one defining the lens opening of an eyeglass frame includes a tracer element moved automatically about a rotational axis surrounded by the traced surface and arranged perpendicularly to the area enclosed by the surface. As this rotation occurs a carrier for the tracer element is moved along a second axis extending perpendicularly to the rotational axis in response to a position error signal developed by the tracer element to maintain the position error signal at a substantially zero value through the use of feedback circuitry. The positions of the carrier about the rotational axis and along the second axis are repeatedly captured during the tracing movement to provide point data defining the shape of the traced surface. Results are a smooth steady movement of the tracer element along the surface with a minimum amount of force being exerted on the traced surface by the tracer element.