A fan device includes a hub and a plurality of fan blades. Each of the fan blades includes a driving surface, and the driving surface includes a first tooth column and a second tooth column. The first tooth column includes a plurality of first skin-tooth units. Each of the first skin-tooth units includes a first body. A first middle ridge and two first side ridges protrude from a surface of the first body, and a groove is formed between two adjacent first skin-tooth units. The second tooth column includes a plurality of second skin-tooth units. Each of the second skin-tooth units includes a second body and an extension element. A second middle ridge and two second side ridges protrude from a surface of the second body, and the extension element is located in the groove and includes an extension rib.

A diagonal fan having an electric motor and a diagonal impeller which can be driven about an axis of rotation (RA) by means of the electric motor. The diagonal impeller determines an air inlet and an air outlet and has a hub and impeller vanes which are distributed in the circumferential direction, extend radially outwards from the hub and are surrounded radially externally by a slinger ring. A flow angle αD formed by the slinger ring relative to the axis of rotation (RA) increases from the air inlet to the air outlet, and a flow angle αN formed by the hub relative to the axis of rotation (RA) decreases from the air inlet to the air outlet.

A counter-rotating fan, comprising an impeller assembly and an air guide structure. The impeller assembly comprises a first stage impeller and a second stage impeller, of which the rotation directions are opposite. The pressure surfaces of first blades of the first stage impeller are configured to be opposite the suction surfaces of second blades of the second stage impeller, and from the blade root to the blade tip, each of the first blades and the second blades bends toward its own rotation direction. The air guide structure comprises a flow guide cover. The flow guide cover is provided at the center position of the air intake side of the first stage impeller, and the air intake side surface of the flow guide cover at least partially forms a flow guide surface, the flow guide surface extending along the axis of the first stage impeller in the direction away from the counter-rotating fan.

A serial-type diagonal fan assembly having a first fan and at least one second fan is provided. The first fan has a first front fan frame and a first fan wheel. A first hub of the first fan wheel has a radial cross-sectional area increased from a top toward a bottom of the first hub. The second fan has a second front fan frame and a second fan wheel, the second hub of the second fan wheel has an axial cross-sectional area increased from a top to a bottom of the second hub. The first fan and the second fan are arranged in a series. A spoiler is arranged on a second air inlet of the second front fan frame, an outer edge of the spoiler is embedded in a positioning groove of the second front fan frame without protruding from the second front fan frame.

In a blade of a propeller fan, an inclination angle (φ) is made by a straight line passing through an outer circumferential side end and an inner circumferential side end of a radial cross section of the blade with a second plane orthogonal to a center axis of a hub. In a blade end of the blade, one end in front of the other end viewed in the rotation direction of the propeller fan is a leading blade end, while the other end behind the leading blade end is a trailing blade end. The blade is shaped such that the inclination angle (φ) monotonically increases, in the direction from the intermediate position toward the trailing blade end, in an area extending from an intermediate position between the leading blade end and the trailing blade end to the trailing blade end.

A fan wheel and a radiator of a motor vehicle, the fan wheel having a hub to which a number of fan blades is connected. The fan blades each have a stabilizing structure of a first material, which is surrounded by means of a respective body of a second material.

The cooling fan module may include a fan assembly and a fan shroud. The fan shroud of the cooling fan module may include a first sidewall that may extend in a radial direction and define an opening. The fan assembly may include a hub disposed within the opening, a blade extending from the hub to a distal end that may include a first side and a second side converging to form a first leading edge with respect to the rotational direction. The fan assembly may include a winglet that may include a first fin, extending in the axial direction from the distal end of the blade and a second fin extending in the radial direction.

An inner peripheral blade projects from the positive pressure surface of the blade surface part toward a positive pressure side, includes a front edge in a rotation direction of the inner peripheral blade that is formed in a curved shape to be separated from a reference line toward the front edge side in the rotation direction of the blade, the reference line connecting a lower end positioned on the positive pressure surface at a base end of the inner peripheral blade connected to the side surface of the hub with an outer edge of the inner peripheral blade that is extended from the side surface toward an outer edge side of the blade and positioned on the positive pressure surface, and satisfies H/L≥0.1, where L is a length of the reference line and H is a maximum value of a distance between the reference line and the front edge of the inner peripheral blade.

A propeller fan includes a shaft portion disposed on a rotation axis, and a blade disposed on an outer peripheral side of the shaft portion and including a leading edge and a trailing edge. The blade includes a negative pressure surface in which a plurality of recesses are formed, and the plurality of recesses include a first recess and a second recess disposed on the trailing edge side than the first recess in a circumferential direction about the rotation axis as a center. The first recess has a depth larger than a depth of the second recess.

A blade for room fans comprising an elongated body extending longitudinally along a longitudinal direction of development and provided with a first end mounted, in use, on a central body movable in rotation around an axis of rotation orthogonal to the direction of development for the movement of at least one air flow intended for the airing/ventilation of rooms, and a second end opposite said first end, the elongated body rotating arranged on a plane of rotation orthogonal to the axis of rotation; wherein the elongated body is provided with a cross section the inclination of which with respect to the plane of rotation and/or the conformation of which varies along the direction of development.