Machine for welding at least one run of rail

A welding machine for welding a stretch of new rails to replace old rails already laid on a railroad track, comprising:

• a vehicle adapted to run along said old rails of said track on two bogies, said vehicle being equipped with at least one energy generator set;
• a raised chassis carried by said vehicle between said bogies for carrying out operations on said new rails below said chassis and between said old tracks;
• at least one welding unit for welding joints in said new rails, said welding unit being moveably supported on said chassis for longitudinal, transverse and vertical movement thereon;
• grinding means for grinding joints welded in said new rails, said grinding means being moveably supported on said chassis for longitudinal, transverse and vertical movement thereon;
• two workbench units, each said workbench unit comprising a beam, each said beam respectively supporting first and second gripping means for gripping and lifting inner ends of said new rails into a working position and for supporting said new rails in said working position, each said workbench unit being moveably supported on said chassis for longitudinal, transverse and vertical movement thereon;
• a pair of grippers disposed at each end of said vehicle and operating cooperatively with said first and second gripping means to grip and lift outer ends of said new rails into said working position and to support said new rails in said working position, each said workbench unit being moveably supported on said chassis for transverse and vertical movement thereon;
• position sensors for continuously determining the positions of said welding unit, said grinding means, said workbench units, said gripping means, and said grippers relative to a set of othogonal axes, X, Y and Z, said X-axis being parallel to said track, said Y-axis being parallel to cross-ties of said track, and said Z-axis being perpendicular to an XY plane;
• a programmable automatic control unit in said vehicle for controlling operations of said machine, said control unit being capable of generating signals for controlling displacements of said welding unit, said grinding means, said work bench units, said first and second gripping means, and said grippers;
• and,
• transmitting means in said vehicle for transmitting positions determined by said positional sensors to said control unit and for transmitting said displacement control signals generated by said control unit to said welding unit, said grinding means, said work bench units, said first and second gripping means, and said grippers.