A fan includes a hub and a plurality of fan blades. The hub has an axle center. The fan blades are disposed around the hub. Each of the fan blades has a bent portion, and the bent portions of the fan blades are extended along a surrounding direction surrounding the axle center. The hub is welded with the bent portion of each of the fan blades along the surrounding direction. As a result, the number of fan blades is maximized, the strength is simultaneously ensured to be enough, and the advantages of effectively enhancing the fan characteristics are achieved.

A centrifugal blower for HVACR applications includes a squirrel cage forward-curved blower fan and a scroll housing. The blower fan comprises a plurality of blades that are configured to emit air radially outward and tangentially from between the blades when the blower fan rotates at a first speed. The air so emitted has a deviation angle defined as the difference between the direction of the emitted air and the blade exit angle. The scroll housing has a spline-shaped wall that has an axial cross-section that is configured such that the deviation angle of the air emitted from the blower fan at an axial plane deviates by no more than fifteen percent circumferentially about the blower fan in-between the spline-shaped wall and the blower fan and such that the average tangential velocity of air between the spline-shaped wall and the blower fan deviates by no more than thirty percent.

The invention relates to a fan wheel having blades (11) which are distributed over the circumference and are connected to one another in the circumferential direction via at least one ring. The fan wheel consists of at least three integrally formed segments (I to VII). Said segments comprise at least one respective ring portion (1) of at least one ring as well as either a blade (II) or at least a portion of the blades. The segments (I to VII) are joined together to form the fan wheel. The ring portions (1) lie against each other with edges (4, 5) which form the joining areas (15, 16) that are disposed transversely with respect to the circumferential direction of the fan wheel. At least one edge (4) of the ring portion (1) of each segment (I to VII) is provided with at least one projecting form-fitting part (18), and at least one edge (4, 5) of the ring portion (1) of each segment (I to VII) is provided with at least one recess (17) which is at least approximately complementary to the form-fitting part (18).

Provided is a centrifugal fan. The centrifugal fan includes an air inlet, a shaft, and a plurality of blades. The blades are arranged around the shaft. Each of the blades includes an air guiding portion on a side of the blade facing the air inlet. The air guiding portion includes a first curve and a second curve. An air inflow channel is formed between the first curve and the second curve of two adjacent air guiding portions respectively. A width of the air inflow channel is expanded in a direction away from the air inlet according to an expanding ratio.

A profiled blade for a fan impeller comprising a profiled body produced from at least one bent sheet metal strip. The profiled body includes a profile top part with a convex curvature, a profile bottom part located at a distance from the profile top part, and first and second profile noses. Each of the profile noses has a convex curvature and joins the profile top part to the profile bottom part at ends of the profiled body. The profile top part and/or the profile bottom part is divided into at least first and second profile sections. The first profile section is joined to the first profile nose and the second profile section is joined to the second profile nose. A first free end region of the first profile section is joined to a second free end region of the second profile section by adhesive force.

A ventilation assembly having a main housing that can be pre-installed in a wall or ceiling aperture. A fan assembly can be inserted through the aperture and releasably mounted within the main housing. The fan assembly can be removed from the main housing and replaced without removing the main housing from the wall or ceiling. An accessory component can be releasably mounted to the fan assembly either through the aperture when the fan assembly is mounted or prior to installation of the fan assembly.

An extraction blower having a housing having a main air chamber, a debris chamber and a particulate removal port connected to the debris chamber, an impeller configured to rotate within the housing about a central axis and having a base plate positioned in the debris chamber, a plurality of front-facing blades mounted on a front side of the base plate and a plurality of rear-facing blades mounted on a rear side of the base plate.

A blower and a method for decreasing eddy noise are provided. The blower includes a fan frame, a fan wheel, at least one induction element and a coil. The fan frame has in inlet and an outlet. The fan wheel is disposed in the fan frame and has a wheel hub and a plurality of fan blades connected to periphery of the wheel hub. The induction elements are fixed to the corresponding fan blades, the coil is disposed on the fan frame for driving the at least one induction element, such that the fan blade corresponding to the induction element swing back and forth to generate a vibration sound, and the vibration sound is counteracted with eddy noise generated when the fan wheel rotates. Moreover, the method for decreasing eddy noise is also provided.

A blower wheel for use in a blower assembly is disclosed, wherein the blower wheel includes a hub, a concentrically arranged outer ring, and an array of spaced apart blades arranged on an outer periphery of the hub and extending between the hub and the outer ring. The hub includes a wave configuration formed therein. The wave configuration includes an annular array of crests and an annular of troughs alternately formed in at least one of an outer surface and an inner surface of the hub. The hub may also include an annular array of support members formed on the inner surface thereof.

A fan (1) for a smoke and/or vapour extraction system that includes an impeller (3) located within a diffuser or volute (2), the impeller (3) being driven by an electric motor (24); the impeller (3) having a body (20) having a flat part (21) from which a plurality of radially arranged blades (33) extend; these blades are separated from each other by a variable distance based on a periodic function. In addition to this, the diffuser (2) has an air delivery or discharge conduit (5) having a cross-section increasing from an inlet to its outlet (6).