A cooling fan and an electronic device are provided. The cooling fan comprises a plurality of blades disposed in a circumferential direction of a rotating shaft. The plurality of blades includes a first blade and a second blade. A windward surface of the first blade includes a first alignment part and a first offset part. The first alignment part is aligned with a windward surface of the second blade, and the first offset part and the windward surface of the second blade are arranged in a staggered manner.

A cooling fan and an electronic device are provided. The cooling fan comprises a plurality of blades disposed in a circumferential direction of a rotating shaft. The plurality of blades includes a first blade and a second blade. A windward surface of the first blade includes a first alignment part and a first offset part. The first alignment part is aligned with a windward surface of the second blade, and the first offset part and the windward surface of the second blade are arranged in a staggered manner.

An upstream space forming portion of a centrifugal blower has a space division portion that divides an upstream space into an inner connection space and an outer connection space. The outer connection space has an overlapping space that overlaps the space division portion in an axial direction, and a non-overlapping space excluding the overlapping space from the outer connection space. A suction port has an outer overlapping portion located outside the separation cylinder in a radial direction, and an outer non-overlapping portion excluding the outer overlapping portion from the separation cylinder located outside in the radial direction. A relationship S1/S2≥0.5 is satisfied when a first area S1 is defined by projecting a boundary between the overlapping space and the non-overlapping space in the radial direction, and a second area S2 is defined by projecting the outer overlapping portion in the axial direction.

An upstream space forming portion of a centrifugal blower has a space division portion that divides an upstream space into an inner connection space and an outer connection space. The outer connection space has an overlapping space that overlaps the space division portion in an axial direction, and a non-overlapping space excluding the overlapping space from the outer connection space. A suction port has an outer overlapping portion located outside the separation cylinder in a radial direction, and an outer non-overlapping portion excluding the outer overlapping portion from the separation cylinder located outside in the radial direction. A relationship S1/S2≥0.5 is satisfied when a first area S1 is defined by projecting a boundary between the overlapping space and the non-overlapping space in the radial direction, and a second area S2 is defined by projecting the outer overlapping portion in the axial direction.

A blower fan assembly comprising a scroll housing, a forward curved blower wheel, and a blower motor adapted to rotate the blower wheel about a blower wheel axis. The forward-curved blower wheel comprises a plurality of fan blades circumferentially spaced about the blower wheel axis. Each of the fan blades has a leading edge with a leading edge angle and a trailing edge with a trailing edge angle. The leading edge angle is at least 50° and not more than 80°. The trailing edge angle is at least 5.5° and not more than 18.5°. The outer radius is not more than 4 inches (101.6 mm).

A blower fan assembly comprising a scroll housing, a forward curved blower wheel, and a blower motor adapted to rotate the blower wheel about a blower wheel axis. The forward-curved blower wheel comprises a plurality of fan blades circumferentially spaced about the blower wheel axis. Each of the fan blades has a leading edge with a leading edge angle and a trailing edge with a trailing edge angle. The leading edge angle is at least 50° and not more than 80°. The trailing edge angle is at least 5.5° and not more than 18.5°. The outer radius is not more than 4 inches (101.6 mm).

A centrifugal fan includes: a main plate having a rotation center; and a plurality of blades extending from the main plate in a direction of a rotation axis passing the rotation center. A length direction of each blade extends from an inner circumferential side to an outer circumferential side of the main plate. Where a distance between a forward edge of the blade and the rotation center is defined as RA and a distance between the rotation center and a point C between the forward edge and a backward edge of the blade is defined as RC, at least one of the plurality of blades has the point C that satisfies RC<RA.

A centrifugal fan includes: a main plate having a rotation center; and a plurality of blades extending from the main plate in a direction of a rotation axis passing the rotation center. A length direction of each blade extends from an inner circumferential side to an outer circumferential side of the main plate. Where a distance between a forward edge of the blade and the rotation center is defined as RA and a distance between the rotation center and a point C between the forward edge and a backward edge of the blade is defined as RC, at least one of the plurality of blades has the point C that satisfies RC<RA.

The present invention relates to a blower, the blower according to an embodiment of the present invention comprising: a lower case having a suction hole formed therein through which air is introduced; an upper case arranged on the upper side of the lower case and having a discharge hole formed therein through which air is discharged; and a fan arranged in the lower case and including a plurality of blades. Each of the plurality of blades includes a plurality of airfoils respectively extending along different camber lines from one another, and a leading edge of connecting the leading ends of the plurality of airfoils. Entrance angles formed by the respective camber lines of the plurality of airfoils and the rotation directions of the blades are different from one another. Thus, due to the curved shape of the leading edge and the design of a recessed notch, a flow separating from the leading edge is reduced, and thus, there is an advantage in that air volume performance is improved.

A fan with airfoil blades is provided for a regenerative air vacuum street sweeper. The blades are formed using cut and pressed upper and lower panels which are welded at a forward edge to a rod to form the airfoil leading edge and welded at the rear edges to form the airfoil trailing edge. Pins extend laterally outwardly from the rod for mounting each blade in corresponding holes in the front and rear plates of the fan housing. The side edges of the blade are welded to the plates at a 9-11° angle of attack. The airfoil blades allow for reduced size, horse power, noise, and manufacturing and shipping costs.