Abstract: A flame cutting apparatus includes a pair of longitudinally movable gantries and a connecting transverse bridge which mounts carriages with flame cutting torches including a plasma torch unit. A computer numerical controller is fixedly mounted adjacent to one gantry. Position sensors and operating devices are mounted on the bridge with a high frequency supply for igniting the plasma torch and supplemental electronic circuits. The bridge is a generally hollow box-beam having doors within which the supplemental electronic circuitry to mechanically and electronically isolate them. Cables are provided for connecting the bridge mounted sensors and operating devices to an onboard computer controller. A special filter unit is mounted in the controller-mounted gantry. The filter unit includes an enclosure and a plurality of separate filters each of which is connected to a lead of the cable. The filters isolate the controller from electronic noise and extraneous signals in the cables.

Abstract: 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.