MACHINE A PERCER A EMBASE ELECTROMAGNETIQUE COMPRENANT DES DETECTEURS DE SURCHARGE

摘要

A drilling machine provided with an electromagnetic base comprises a first control system by which a warning device is actuated and/or a feed motor for automatically advancing an electric drill toward a workpiece is stopped when a load on the electric drill exceeds a prescribed first reference level while at work. A second control system further provided on the drilling machine is adapted to have the feed motor and/or the electric drill stopped when the load thereon is further increased and reaches a second reference level higher than the first reference level to assure high safety.