Patent ID: 6903300

Claim:
A method for thermally working a workpiece consisting of a ferromagnetic material by means of a thermal working tool ( 1 ) which is moveable along a work-piece surface ( 7 ), and comprises a torch head ( 2 ) which has exchangeably mounted thereon at least one cutting or welding tool, wherein an alternating magnetic field is produced for controlling a working distance (A) between said working tool ( 1 ) and said workpiece surface ( 7 ), said magnetic field acting both in the area of said workpiece surface ( 7 ) and in a sensor body with ferromagnetic properties above said workpiece surface ( 7 ), said magnetic field or changes thereof being sensed by means of a measuring device ( 9 ; 10 ), and measurement signals of said measuring device ( 9 ; 10 ) being evaluated for controlling said working distance (A), characterized in that said torch head ( 2 ) and at least one of the cutting or welding tools ( 3 ; 4 ; 5 ) are used as sensor body ( 2 ; 3 ; 4 ; 5 ).