Wall sleeve for ventilating room i.e. kitchen, has cover lid movable between closing and open positions and driven by pressure difference between air pressure in ventilation pipe and external environment air

摘要

The sleeve has a ventilation opening at a horizontal lying ventilation pipe (2). A cover lid (5) is movable between closing position and open position, is driven by the pressure difference between the air pressure in the ventilation pipe and the external environment air and closes and opens against a resetting force in an automatic manner. The cover lid is axially guided to guiding arms (7) in the ventilation pipe. A pivoted lever (8) is connected with the middle point of the cover lid via a connecting rod. The guiding arms and a flow body (6) are made of plastic.