Roof ventilating device forming a fume outlet

摘要

Device in which a frame or hatchway curb framework is fixed onto the roof around the edge of an opening in this roof, this frame supporting, by means of an articulation, a frame which pivots along one of the sides of the frame or hatchway curb framework, characterised by at least one spring 13 connected to a fixed point of the frame or hatchway curb framework 2 and to a lever 15 articulated on a spindle 14 which is also supported by a frame or hatchway curb framework 2, the said lever 15 being connected by means of a damping cylinder (dashpot) 17 to the pivoting frame 10. <IMAGE>