Development of Force-Control Model for Edge-Deburring With Filamentary Brush

Abstract

In recent years, edge finishing with filamentary brushes has received much attention within the applied research and manufacturing engineering communities. This interest may be attributed, in part, to the ease with which brushing tools can be introduced into an automated machining environment. That is, such tools exert relatively small machining forces, remove material incrementally, and minimize the risk of generating abrupt, unstable forces that can lead to tool/workpart damage during the finishing operation. Although brushes have been successfully used in automated finishing applications, much uncertainty remains regarding the proper use of brushes for removal of edge burrs. Consequently, the implementation of automated brush deburring operations is often accompanied by costly trial-and-error experimentation, and in many cases, is met with only marginal success. This paper is concerned with the development of a force-control model for edge deburring with filamentary brushes. The model is based upon experimentally obtained “master curves”; that is, material removal data that corresponds to the actual machining performance of the brush/workpart system during the incremental burr removal process. Such master curves are generated by machining specially prepared edge projections having a geometry similar to flash that is produced along the edges of cast components. This information is used in conjunction with the on-line brush machining force to compute the brush feed rate that ensures complete removal of the edge burr. Example problems are reported for two cases, namely, the removal of edge flash having (i) unknown, constant height, and (ii) unknown variable height. The results indicate that the present force-control model provides straight forward approach for computing brush feed rates that lead to complete removal of edge burrs, and suggests that implementation can be carried out without the use of sophisticated sensing apparatus or complex control strategies.