Metal machining device with control circuit isolation

摘要

A metal machining device includes a pair of longitudinally movable gantries and a connecting transverse bridge which mounts carriages which carry machining tools. A computer numerical control unit is fixedly mounted adjacent one end of the bridge and is connected to supplemental electronic circuits. The transverse tool-carrying bridge is formed as a generally hollow heavy-walled closed box-beam which has mounted therein at least part of the supplemental electronic circuitry. A beam side-wall is provided with a plurality of doors which open to permit access to a plurality of circuit-holding drawers. When the doors are closed, the bridge forms a unitary hollow housing containing the supplemental electronic circuitry which serves to mechanically and electronically isolate them and substantially reduce the radiation of electronic noise therefrom to the computer. The removal and harness-like fixing of at least some of the connecting electronic cables to within the bridge serves to reduce the problems of electronic coupling and other interference. Further improvement in isolating is accomplished by placing progressively noisier supplemental circuits in drawers which are progressively farther away from the computer.