A wind wheel including a first air plate, a second air plate, and a plurality of blades disposed between the first air plate and the second air plate. The first air plate includes a central part and an air inlet disposed in the central part; each two adjacent blades form an air duct. The plurality of blades each includes an inlet section next to the air inlet, an intermediate section, and an outlet section. The thickness of the intermediate section is greater than the thickness of the inlet section and the thickness of the outlet section.

A centrifugal blower includes a blower base, multiple blades fastened to the blower base, a hub integrated to a central portion of the blower base, and a top shroud to provide surrounding coverage to the multiple blades. The centrifugal blower is housed within an evaporator. The centrifugal blower may operate at operating speeds that are lower than those of typical or currently known implementations while generating an airflow that meets or even exceeds those of the typical or currently known implementations.

An impeller includes a main plate, an annular side plate and blades. The blades each have: an inner circumferential end; an outer circumferential end; a sirocco blade portion formed as a forward-swept blade portion, and having an outlet angle that is greater than 90 degrees; and a turbo blade portion formed as a swept-back blade portion and including the inner circumferential end. The blades include a first blade portion and a second blade portion that are provided on respective sides of the main plate. The impeller including a region in which a first inter-blade distance is greater than a second inter-blade distance, where an inlet-blade distance is a distance between any adjacent two of the blades in the circumferential direction, the first inter-blade distance is the inter-blade distance of the first blade portion, and the second inter-blade distance is the inter-blade distance of the second blade portion.

An impeller includes a main plate, an annular side plate and blades. The blades each have: an inner circumferential end; an outer circumferential end; a sirocco blade portion formed as a forward-swept blade portion, and having an outlet angle that is greater than 90 degrees; and a turbo blade portion formed as a swept-back blade portion and including the inner circumferential end. The blades include a first blade portion and a second blade portion that are provided on respective sides of the main plate. The impeller including a region in which a first inter-blade distance is greater than a second inter-blade distance, where an inlet-blade distance is a distance between any adjacent two of the blades in the circumferential direction, the first inter-blade distance is the inter-blade distance of the first blade portion, and the second inter-blade distance is the inter-blade distance of the second blade portion.

An air duct component includes first and second volute members arranged oppositely in a cross section perpendicular to an axis of a cross-flow impeller. An inner end of the first volute member includes a volute tongue. A cross-flow air duct formed between the first and second volute members includes a middle air duct section and an end air duct section arranged along an axial direction of the cross-flow impeller. The middle air duct section includes a middle air outlet duct located downstream of a vertical line that passes through the volute tongue and is perpendicular to the second volute member. The end air duct section includes an end air outlet duct located downstream of the vertical line. A cross-sectional area of the middle air outlet duct is larger than a cross-sectional area of the end air outlet duct.

An air duct component includes first and second volute members arranged oppositely in a cross section perpendicular to an axis of a cross-flow impeller. An inner end of the first volute member includes a volute tongue. A cross-flow air duct formed between the first and second volute members includes a middle air duct section and an end air duct section arranged along an axial direction of the cross-flow impeller. The middle air duct section includes a middle air outlet duct located downstream of a vertical line that passes through the volute tongue and is perpendicular to the second volute member. The end air duct section includes an end air outlet duct located downstream of the vertical line. A cross-sectional area of the middle air outlet duct is larger than a cross-sectional area of the end air outlet duct.

A fan wheel (1) has a bottom disc (4), a cover disc (3) and impeller blades (2) arranged around a rotation axis (RA) of the fan wheel (1). The blades, in each case, extend over a blade length from a blade leading edge (5) to a blade trailing edge (6). The impeller blades (2) are divided into a front section (10), rear section (12) and transition section (11). The front section (10), extends proceeding from the blade leading edge (5) in the direction of the blade trailing edge (6). The rear section (12) extends proceeding from the blade trailing edge (6), in the direction of the blade leading edge (5). The transition section (11) forms a transition between the front section (10) and the rear section (12). The impeller blades (2) are formed with opposite curvature in the course from the bottom disc (4) to the cover disc (3) in the front section (10) and the rear section (12).

A fan wheel (1) has a bottom disc (4), a cover disc (3) and impeller blades (2) arranged around a rotation axis (RA) of the fan wheel (1). The blades, in each case, extend over a blade length from a blade leading edge (5) to a blade trailing edge (6). The impeller blades (2) are divided into a front section (10), rear section (12) and transition section (11). The front section (10), extends proceeding from the blade leading edge (5) in the direction of the blade trailing edge (6). The rear section (12) extends proceeding from the blade trailing edge (6), in the direction of the blade leading edge (5). The transition section (11) forms a transition between the front section (10) and the rear section (12). The impeller blades (2) are formed with opposite curvature in the course from the bottom disc (4) to the cover disc (3) in the front section (10) and the rear section (12).

Embodiments of the invention provide a blowing apparatus comprising a body including an impeller equipped with vanes including an opening therein to allow air to pass through the vane when the impeller is rotating.

A closed impeller includes an impeller body including a plurality of blade portions, and a shroud fitted on the impeller body. The shroud is press formed into a curved shape along end portions of the blade portions. The shroud includes a plurality of protrusions protruding from a surface facing the impeller body and extending, and curved, along the end portions of the plurality of blade portions. An amount of protrusion of each of the protrusions is less than a thickness of the shroud. A brazing material is provided at least on end portions of the protrusions.