Device for fastening a C-shaped mounting rail to a wall provided with screw holes

A device for fastening an end of a C-shaped mounting rail to a wall with holes of one of a control cabinet and a frame piece of said control cabinet frame, having a fastening block which is inserted into said end and is adapted to an inside cross section of said mounting rail and is fastened by means of a fastening screw in said wall, the improvement comprising:

• said wall (14) having a first row of rectangular cutouts (12) and, having between said cutouts and being offset by one-half spacing, a second row of screw holes (13),
• said fastening block (20) being closed off with a fastening plate (24) on a side facing said wall (14),
• said fastening plate (24) having an L-shaped hanger (25) on said side facing said wall (14) adapted to said cutouts (12) and a thickness of said wall (14) and hung in said cutout (12),
• said fastening plate (24) having a screw hole (26) positioned outside of said fastening block (20) for a fastening tap screw (27) which can be screwed into one of said screw holes (13) in said wall (14) when said fastening plate (24) has been hung,
• said fastening block (20) having a U-shaped recess (21) which defines a square nut (22) with a threaded bore (23) on three sides, and
• said threaded bore (23) being directed crosswise to a longitudinal axis of said mounting rail (10) and vertically to a base leg of said mounting rail and receiving a tensioning screw (28) for an axial seating of said fastening block (20) in said mounting rail (10).