A shed forming device for a weaving machine, comprising a working space (3) in which shed forming systems having selection means for the positioning of warp threads are provided, and ventilation means (7) to create an air flow (A) in this working space (3), wherein the ventilation means (7) interact with regulating means (8, 9, 10) for automatically regulating the air flow rate as a function of at least one of the following measured parameters: the flow rate and the velocity of the air flow (A) and the air pressure in the working space (3). As a result, the air flow rate can be rapidly adapted to changing conditions and can always be appropriate for efficient cooling and for creation of an overpressure.

A shed forming device for a weaving machine, comprising a working space (3) in which shed forming systems having selection means for the positioning of warp threads are provided, and ventilation means (7) to create an air flow (A) in this working space (3), wherein the ventilation means (7) interact with regulating means (8, 9, 10) for automatically regulating the air flow rate as a function of at least one of the following measured parameters: the flow rate and the velocity of the air flow (A) and the air pressure in the working space (3). As a result, the air flow rate can be rapidly adapted to changing conditions and can always be appropriate for efficient cooling and for creation of an overpressure.