Abstract: The invention relates to a centrifugal fan impeller (1) having an axis of rotation (6) and comprising one or more modules (2). Each module (2) comprises a mounting disc (4), at least one connecting ring (5) and a plurality of blades (3) extending between the mounting disc (4) and the connecting ring (5). The blades (3) are connected to the disc (4) and ring (5) at an angle (?) relative to the axis (6) of the impeller (1). The angle (?) at which the blades (3) are inclined may range from 5 to 30 degrees and the blades (3) may be rectangular or trapezoidal in shape depending on the type of performance required: improved capacity with rectangular blades or improved pressure head and acoustic properties with trapezoidal blades. Top performance is thus combined with acoustic comfort.

Abstract: The invention relates to a centrifugal fan impeller (1) having an axis of rotation (6) and comprising one or more modules (2). Each module (2) comprises a mounting disc (4), at least one connecting ring (5) and a plurality of blades (3) extending between the mounting disc (4) and the connecting ring (5). The blades (3) are connected to the disc (4) and ring (5) at an angle (?) relative to the axis (6) of the impeller (1). The angle (?) at which the blades (3) are inclined may range from 5 to 30 degrees and the blades (3) may be rectangular or trapezoidal in shape depending on the type of performance required: improved capacity with rectangular blades or improved pressure head and acoustic properties with trapezoidal blades. Top performance is thus combined with acoustic comfort.