Abstract: A blade for an industrial axial fan has a first wing-shaped body having a first leading edge and a first trailing edge; a second wing-shaped body having a second leading edge and a second trailing edge inclined with respect to said keying axis and the first leading edge and the second trailing edge; and a third wing-shaped body having a third leading edge and a third trailing edge inclined with respect to said keying axis in the opposite direction to the inclination of the second leading edge and to the second trailing edge so as to define an entry vertex between the second and third leading edges.

Abstract: A blade for an industrial axial fan includes an airfoil, extending along a blade axis and having a leading edge, a trailing edge, a root side, a tip side; and a rod, having a first end connected to the airfoil and a second end protruding from the airfoil for coupling to a hub. The root side has a rounded contour with a concave stretch adjacent to the leading edge and a convex stretch adjacent to the trailing edge. A root end of the leading edge protrudes with respect to the insertion point toward the second end of the rod in a direction parallel to the blade axis. The airfoil forms a lobe that extends in the direction parallel to the blade axis toward the second end of the rod more than with respect to the root end of the leading edge. The airfoil is extruded or pultruded and the leading edge is rectilinear and parallel to the blade axis.

Abstract: A blade for an industrial axial fan includes an extruded or pultruded airfoil, extending along a blade axis and having a leading edge, a trailing edge, a root side and a tip side, an intrados and an extrados. A terminal member is arranged to close the tip side and has a rounded front portion in a plan view at the leading edge and a rounded rear portion in a plan view between the front portion and the trailing edge.

Abstract: Described herein is a blade system (10) for fans for industrial use, comprising: —a blade (12), which extends longitudinally along a first reference axis (K) and defines within it a cavity (12A), wherein said blade has a cross section with flattened profile and is oriented with a major dimension (L1) along a second reference axis (H); and—a supporting unit (14), on which said blade (12) is fixed and which is inserted within the cavity (12A) of said blade, said supporting unit (14) being designed to be connected to the rotor (2) of a fan.

Abstract: Described herein is a blade unit for industrial fans, which comprises: a blade; and a tubular bar, fixed on which is said blade and which has a root portion configured for being engaged by means for connecting said bar to the rotor of a fan. The unit is characterized in that it comprises a further bar mounted within said first tubular bar so as to present a first portion axially constrained to said first bar, and a second portion that is, instead, able to slide with respect to said first bar, in a condition of sliding friction, following upon a deformation due to bending of said first bar.

Abstract: An axial fan comprises a hub and a plurality of blades extending from the hub; wherein each blade comprises a main blade portion and a secondary blade portion and the secondary blade portion has a leading edge adjacent to a leading edge of the main blade portion and forms a flap for the main blade portion; wherein a fluid passage is defined between the leading edge of the main blade portion and the leading edge of the secondary blade portion; wherein the main blade portion has a main chord and the secondary blade portion has a secondary chord; and wherein the main chord and the secondary chord form a relative attack angle comprised between 5° and 35°.

Abstract: A hollow extruded axial flow fan blade which includes two internal longitudinal reinforcing elements (ribs) perpendicular to the blade profile and in which are inserted through bolts for fastening the blade to a round supporting bar inserted longitudinally in the blade. The fastening bolts are completely internal to said blade being parallel to the plane of revolution of the blade while passing diametrally and perpendicularly through the round supporting bar.

Abstract: The present invention relates to fixed-angle keying pieces for blades of axial fans each having a U-shaped cross section, the internal surface of which perfectly fits the profile of the blade while the external surface of the same has a plane side face which rests on a supporting plate, the keying piece being obtained as a continuous extruded section which is subsequently cut to a desired size.

Abstract: According to the invention an increase of the effective displacement of air in an axial propeller, whose blades are not twisted, is achieved by applications of tab, substantially rigid, at the trailing edge of the blade, the maximum width of the tab being at the blade internal end.