Screening arrangement for a window

A screening arrangement for a window with a frame-shaped main frame adapted for fixed installation in a roof or wall opening and a glass-carrying frame journalled in the main frame, wherein the glass-carrying frame from a closed position, in which the glass-carrying frame is in a plane parallel to that of the main frame, can be moved to a ventilating position, in which the glass-carrying frame plane forms an angle with the main frame plane, so that at least one wedge-shaped ventilation aperture having a rectangular face and two triangular side faces is defined between the main frame and the glass-carrying frame, said screening arrangement comprising an air-permeable insect screen, which in a mounted position comprises three wall-like sections for screening the rectangular and the two triangular side faces, respectively, of the wedge-shaped ventilation aperture, each section of the insect screen defining a bellows surface having an outer and an inner end fold, the inner end fold being connected with the main frame and the outer end fold being carried by a screen-carrying frame connected to the main frame by hinges to define a hinged connection, wherein the screen-carrying frame is a separate frame for mounting on the outside of the glass-carrying frame, and the screen-carrying frame, at a distance from its hinged connection with the main frame, is displaceably connected with the glass-carrying frame.