Abstract: An exhaust fan assembly can include an outer housing, a fan housing mounted to the outer housing, a fan wheel and an electric motor operably coupled to the fan wheel, the fan wheel and electric motor being mounted within the fan housing, wherein the fan housing defines an open inlet side for accepting airflow in a direction generally parallel to a rotational axis of the fan wheel and an outlet for discharging airflow in a direction generally perpendicular to the rotational axis, wherein the fan housing defines a volute section with an outer perimeter having a continuously curved cross-sectional shape.

Abstract: A gear unit having a shaft, particularly an input shaft, a fan impeller being joined in rotatably fixed manner to the shaft, a fan cowl, which at least partially surrounds the fan impeller, being mounted on the gear housing, a separating plate for separating the pressure chamber of the fan from the suction chamber of the fan being joined to the fan cowl, the separating plate having an air inlet for the fan impeller and being disposed on the side of the fan impeller facing away axially from the gear unit.

Abstract: A dust management system for an agricultural harvester includes a perforated tube extending transversely through a feeder housing of the harvester. The perforated tube has exhaust plenums at opposite ends directing any flow towards the ground over which an agricultural harvester operates. A longitudinal drive shaft mounts axial flow fans within the exhaust plenums and a drive shaft is driven through a pulley system so that rotation of the drive shaft induces flow through the perforated tube and out of the exhaust plenum.

Abstract: A gear unit having a shaft, in particular an input shaft, a fan impeller being connected to the shaft in a torsionally fixed manner, a fan hood being connected to the gear unit housing, which at least partially encloses the fan impeller, a separation plate for separating the pressure chamber of the fan from the suction chamber of the fan being connected to the fan hood, where the separation plate has an air intake opening for the fan impeller and is situated on the side of the fan impeller facing axially away from the gear unit, the fan impeller has an upper and a lower cover disk, which are axially set apart from each other, and fan blades are disposed between the cover disks, so that channels are formed, the radial clearance of the air intake opening being disposed within, especially centrally within, the radial clearance region covered by the upper cover disk, and the air intake opening is disposed axially within, especially centrally within, the axial region covered by the upper cover disk.

Abstract: A method of manufacturing a centrifugal fan is provided that includes cutting a metal sheet to form a positive pressure surface forming member and a negative pressure surface forming member, respectively, forming a positive pressure surface and a negative pressure surface; pressing the positive pressure surface forming member and the negative pressure surface forming member to form a first curved surface forming the positive pressure surface and a second curved surface forming the negative pressure surface; trimming the positive pressure surface forming member provided with the fast curved surface and the negative pressure surface forming member provided with the second curved surface to form a shroud bonding surface and a main plate bonding surface; bending the shroud bonding surface and the main plate bonding surface; bonding the positive pressure surface forming member and the negative pressure surface forming member to each other; and bonding the shroud bonding surface and a shroud to each other and bondi

Abstract: A forward curved blade impeller for an industrial fan assembly includes an impeller hub assembly, an impeller baseplate mounted on the impeller hub assembly and having an annular shape, a first impeller ring having an annular shape, and an impeller blade deck having a plurality of first impeller blades extending between, circumferentially spaced about and secured to the impeller baseplate and the first impeller ring. A plurality of reinforcement bars extend between, are circumferentially spaced about and are secured to the impeller baseplate and the first impeller ring. Additional impeller blade decks and impeller rings may be stacked above the first impeller blade deck and first impeller ring, with the reinforcement bars extending from the impeller baseplate through intermediate impeller rings to a topmost one of the impeller rings.

Abstract: An impeller wheel for fans has a bottom disc, a cover disc, and three-dimensionally shaped blades connected to the bottom disc and the cover disc. The bottom disc, cover disc, and the blades form a one-piece part. The blades have a leading edge and a trailing edge, wherein the leading edge and the trailing edge each have a median diameter. In a projection onto a cylinder that is coaxial with a rotation axis of the impeller wheel and has a diameter matching a median diameter of the trailing edge or of the leading edge, a first extension of the trailing edge and/or the leading edge is positioned at a first angle and a second extension of the trailing edge and/or the leading edge is positioned at a second angle relative to a line parallel to the rotation axis. At least one of the first and second angles is different from 0°.

Abstract: A fan structure includes a first fixing ring and a plurality of fan blades. The first fixing ring includes a plurality of first recesses radially arranged on the first fixing ring. One side of the fan blades is coupled to the first recesses of the first fixing ring. The first fixing ring includes a stamped part and a non-stamped part, in which the stamped part is in contact with the fan blades, and the thickness of the stamped part is smaller to the thickness of the non-stamped part.

Abstract: Embodiments of the application disclose a fan and a mold for making a fan blade structure for the fan. An embodiment of the fan comprises a fan blade structure and the fan blade structure comprises a mounting ring and a plurality of fan blades provided on the mounting ring, wherein mounting ring and the fan blades are integrally formed. The mold comprises a mounting ring and a plurality of fan blades provided on the mounting ring, the mold comprising a cavity having a ring-shaped channel configured for forming the mounting ring and a plurality of fan blade channels configured for forming the plurality of fan blades, in order to integrally form the fan blade structure.

Abstract: A centrifugal fan includes a plurality of fan blades circumferentially spaced apart from each other. The fan blade has a front edge portion to which air flows in a rear edge portion from which air flows out, and a blade surface extending between the front and rear edge portions. The blade surface includes a pressure surface on the rotation direction side of the centrifugal fan and a suction surface arranged on the back side of the pressure surface. The fan blade has a cross-sectional shape with concave portions formed at the pressure surface and the suction surface. Such a fan has an excellent blowing capacity. A molding die for use in production of the centrifugal fan, and a fluid feeder provided with the centrifugal fan are disclosed.

Abstract: A cross-flow fan includes a plurality of fan blades circumferentially spaced from each other. The fan blade has an inner edge portion on the radially inner side, and an outer edge portion on the radially outer side. A blade surface extends between the inner edge portion and the outer edge portion. The blade surface includes a pressure surface on the rotation direction side of the fan and a suction surface on the opposite side. In cross-section orthogonal to the rotation axis of the fan, the fan blade has a concave portions formed at the pressure surface and the suction surface. A plurality of concave portions are formed at pressure surface. Side fan provides excellent blowing capacity. Also disclosed are a molding die for use in production of the cross-flow fan, and a fluid feeder provided with the cross-flow fan.

Abstract: A blade wheel for a rotary electric machine may include a hollow cylindrical main body having an outer surface extending around an axis of rotation in a circumferential direction of the main body; a first end region and a second end region of the main body, each peripherally extending around the main body in the circumferential direction, the first and second end regions lying opposite each other in the direction of the axis of rotation; a recess extending along the outer surface and between the first end region and the second end region of the main body in the circumferential direction; and at least one web-shaped vortexing element extending within the recess and between the first and second end regions. The at least one vortexing element is designed to generate a movement of air away from the outer surface when the blade wheel rotates about the axis of rotation.

Abstract: In one aspect, a fan assembly is provided that can be manufactured while producing a significantly reduced amount of scrap material. More specifically, the fan assembly utilizes a hub ring and one or more hub strips to support a plurality of blades rather than a solid center disc or end disc used by some prior approaches. In another aspect, a method is provided that includes bending a member into an annular configuration and joining end portions of the member together to rigidly fix the member in the annular configuration. The rigid annular member may be used as an end ring, a hub ring, an orifice, or other component, while producing significantly less scrap material than traditional approaches.

Abstract: A water turbine is disclosed comprising a rotor mounted to be rotatable about an axis. The rotor comprises at least three blades for causing the rotor to rotate about the axis when the blades are located in flowing water. The rotor comprises a plurality of members in the form of a triangulated structure, and at least one of said members comprises one of said blades.

Abstract: A centrifugal multiblade fan includes a rotatable shaft, blades, a side shroud, and a main shroud. A front edge has a shape inclined radially outward in a direction from the main shroud toward the side shroud. When viewed from an axial direction, a corner part on a positive pressure surface-side is located on a tangential line of a positive pressure surface reference curve at a positive pressure surface side reference corner part, and when viewed from the axial direction, a curvature radius of a negative pressure surface becomes larger in a direction from the side shroud toward the main shroud.

Abstract: A turbo fan includes a main plate rotated by power provided from a fan motor, blades each having one end connected to the main plate to perform rotation movement, and a shroud having an inner circumferential part and an outer circumferential part, an other end of each of the blades connected to the shroud. The shroud includes a plurality of curved parts each having one side connected to the inner circumferential part and an other side connected to the outer circumferential part, the plurality of curved parts each having a predetermined curvature.

Abstract: A method for forming an inclined-blade blower wheel is provided by arranging a plurality of blades about respective circumferences of first and second end caps. The plurality of blades extend longitudinally between the first and second end caps and parallel to an axis defined by respective centers of the first and second end caps. The first end cap is rotated with respect to the second end cap a predetermined amount, therein skewing the plurality of blades at a desired longitudinal pitch between the first end cap and second end cap. The first end cap and second end cap are then rotated in unison while crimping the circumferences of the first end cap and second end cap, therein securing the plurality of blades to the first and second end caps and fixing the desired longitudinal pitch of the plurality of blades from the first end cap to the second end cap.

Abstract: A fan structure comprises a first impeller and a second impeller, wherein the first impeller is composed of a first annular substrate, a plurality of first ribs and a plurality of first blades. The first ribs and the first blades are formed on the first annular substrate, each of the first ribs comprises an engaging hole, and a first accommodating space is formed between each of the adjacent first blades. The second impeller is composed of a hub, a second annular substrate, a plurality of second ribs, a plurality of second blades and at least one engaging member formed on the second ribs. The second ribs and the second blades are formed on the second annular substrate, and a second accommodating space is formed between each of the adjacent second blades. The first blades and the second blades are arranged in a staggered relationship.

Abstract: A vertical axis turbine and method of making same is disclosed. The device and method comprise a plurality of blades rotatably disposed around an axis of rotation at a plurality of blade locations, each blade being twisted at a first angle about its longitudinal axis, each blade having its distal ends located a predetermined distance from the axis of rotation, each blade being bent at one or more central locations along the longitudinal axis so the one or more central locations are the same predetermined distance from the axis of rotation as the distal ends, each blade having a foil cross section perpendicular to the axis of rotation for maintaining unidirectional rotation of that blade about the axis of rotation in a fluid flow, and each blade having its longitudinal axis tilted at a second angle with respect to the axis of rotation.

Abstract: A paddle wheel rotatable about an axis and exposed to radial inward and crosswise water flow has a hub on the axis and about which the wheel is rotated in a rotation direction about the axis and a plurality of angularly spaced blades spaced radially outward from the hub, forming spaces through which water can flow, and each formed by a plurality of radially spaced arcuate elements each in turn having a radially outer end and a radially inner end. These elements are each concave between the respective ends toward the incoming water flow with the radial outer ends more widely spaced than radial inner ends such that each element forms an acute angle with the adjacent element or elements and the spaces between the blades narrow in a direction of flow of water through them.

Abstract: An impeller comprising: a top shroud; a bottom shroud, a plurality of vanes extending from the top shroud to the bottom shroud, each said vane including a top edge at a radially inner portion of the vane in contact with the top shroud and a bottom edge at a radially outer portion of the vane in contact with the bottom shroud, such that a radially inner portion of the vane at the bottom edge of each vane is not in contact with or adjacent the bottom shroud and a radially outer portion of the vane at the top edge of each vane is not in contact with or adjacent the top shroud.

Abstract: A wind turbine has a spindle, a first fan device and a second fan device. The first fan device is rotatably mounted around the spindle and has a first pivot hole and at least two first blades. The first pivot hole is formed through a center of the first fan device and is mounted around the spindle. The at least two first blades are radially mounted on and protrude from an external surface of the first fan device. The second fan device is rotatably mounted around the spindle, abuts with the first fan device and has a second pivot hole and at least two second blades. The second pivot hole is formed through a center of the second fan device and is mounted around the spindle. The at least two second blades are mounted on and protrude from an external surface of the second fan device.

Abstract: This invention relates to a radial blade wheel comprising a first (1,1?) and a second (2,2?) end plate arranged at a mutual distance from each other, the first end plate having an opening (6) which allows inflow to the radial blade wheel, and blades (3) arranged between the first and the second end plate. To achieve optimal efficiency for the radial blade wheel, the radial blade wheel comprises an inner part with blades, in which curvature (R1) of the blades (3) is shaped to bring motion energy to the flowing particles while the radial blade wheel is rotating, and an outer part with blades, in which curvature (R2) of the blades (3) is shaped not to bring motion energy to the flowing particles while the radial blade wheel is rotating.

Abstract: A multi-blade centrifugal fan for preventing circular flows in the end portions of an impeller in the axial direction is provided in a simple structure. The multi-blade centrifugal fan is formed of a fan casing of a scroll type and a multi-blade centrifugal impeller. The fan casing has a bellmouth which becomes an air intake. The multi-blade centrifugal impeller has a number of annularly arranged blades inside the fan casing. The centrifugal impeller draws in air through the intake, which faces the bellmouth, and blows out the air in the centrifugal direction through the blades. A retainer ring is provided in an outer peripheral end portion of the impeller. A cylindrical body is integrally provided in such a manner as to extend from the outer end of the retainer ring, so that circular flows toward the intake side are prevented in the end portions of the impeller.

Abstract: Centrifugal impeller (14) of centrifugal air blower (1) has main plate (15); a plurality of blades (18); ring-shaped plate (20); and a cylindrical wall (22). The blades (18) are circumferentially disposed on the side of the outer periphery of front side (17) of main plate (15). Ring-shaped plate (20) is attached to tip sections (19) of blades (18). Cylindrical wall (22) is disposed on the back side (21) of the main plate (15) so as to be concentric therewith. The structure above provides centrifugal impeller (14) and centrifugal air blower (1) with improved air-blow efficiency and noise-reduced operations.

Abstract: A multiblade air blower has a multiblade impeller, an orifice, an axially overlaid portion, and an airflow collision prevention device. The multiblade impeller includes a main plate and a blade. The blade is provided at the main plate to form a blade inner periphery. The orifice has an open end and an orifice inner periphery. The open end is positioned toward the main plate from a blade end face. The orifice inner periphery has an inner diameter larger than that of the blade inner periphery, and guides air to the multiblade impeller. The axially overlaid portion is a part where the orifice and the blades are overlaid. The airflow collision prevention device is provided at the blade and at an inner side of the orifice inner periphery. The multiblade air blower suppresses loss of air distribution efficiency and increased noise.

Abstract: An impeller of a multiblade fan includes a discoid main plate that rotates about a rotational axis, blades, and a side plate. The blades are disposed annularly about the rotational axis on one side of the main plate, with one end of each of the blades being fixed to an outer peripheral portion of the main plate. The side plate includes an annular side plate body portion that joins outer peripheral edges of the other ends of the blades to each other, an axially extending portion that extends from an opposite-main plate side end of the side plate body portion in the rotational axis direction further than the opposite-main plate side ends of the blades, and a radially extending portion that extends from an outer peripheral end of the side plate body portion further than a radial-direction outer peripheral end of the axially extending portion.

Abstract: A blower wheel comprising a centerdisk comprising a conical portion (16), a planar portion (160) for receiving a hub (7), and an arcuate portion (15) intermediate the conical portion and an outer portion (14), a plurality of blades (2) connected to the outer portion, the blades further connected to a ring (3), and a hub connected to the planar portion, the hub comprising a fastener (13) for attaching the centerdisk to a shaft (200).

Abstract: A centrifugal fan includes a plurality of blades, a first wall disposed at first axial ends of the blades, and a second wall disposed at second axial ends of the blades and having a shaft portion at a center. At least one of the first wall and the second wall has a cutout portion configured to control balance.

Abstract: According to embodiments of the invention, an impeller includes a hub, and a plurality of radial blades for drawing the air inflow axially through the hub and delivering the drawn air radially towards the outside. A ring is attached to one or more tips of the plurality of radial blades to block a portion of the tip toward the inlet side of the impeller. The preferred blockage factor, which is the ratio of a height of the ring to a height of the tip, is approximately in a range between 30% and 40%. By blocking a portion of the tip toward the inlet side of the impeller, the low-momentum flow zone toward the inlet side of impeller is blocked, while the high-momentum flow zone toward the back side of impeller is enhanced. As such, the performance of the impeller is enhanced.

Abstract: An impeller structure includes a hub having a central spindle, and an impeller. The impeller has a top connection ring, a bottom connection ring, a pressure-retaining ring and a plurality of blades vertically arranged around the periphery of the hub. A top side outer edge of each blade is connected with a top connection ring, an bottom side of the inner side of the blade is connected with a bottom connection ring, the outer side is connected with the pressure-retaining ring, and a plurality of ribs extend outwards from the bottom edge of the periphery of the hub connecting with the bottom connection ring. A pressure relief hole is provided between the pressure-retaining ring and the bottom connection ring. When air passes through the pressure relief hole, a pressure effect is generated, increasing air pressure and volume of blower, alleviating turbulence. The pressure-retaining ring also reinforces the blade strength.

Abstract: A vertical axis wind turbine has a stator shaft, an electrical generator, a rotating shaft and multiple blades. The electrical generator is rotatably mounted around the stator shaft. The rotating shaft is mounted on and protrudes from the electrical generator. The multiple blades are disposed around the electrical generator and orientated to balance each other. Each blade is connected to the rotating shaft by at least one strut and has a luff edge tapering to a lee edge. The at least one strut is formed on and protrudes from the blade is connected to the rotating shaft. The blades are rotated by the wind independent of wind direction and rotate the electrical generator to convert wind power into electric power.

Abstract: A resin cross flow fan and a method for manufacturing a resin cross flow fan are provided in which an annealing step can be omitted and the number of circular disks can be reduced, and which provides improved fan strength and air blowing performance. A resin cross flow fan is disposed with a plurality of blades and a plurality of plates. The plurality of blades are annually disposed about a rotation axis. Insertion portions each constituted by a hole or a groove into which each blade is inserted and projecting portions that projects from the periphery of the insertion portions in a direction of the rotation axis are formed on each of the plurality of plates disposed spaced apart in the direction of the rotation axis. Each blade is fixed to the projecting portions by laser welding.

Abstract: A vertical axis turbine and method of making same is disclosed. The device and method comprise a plurality of blades rotatably disposed around an axis of rotation at a plurality of blade locations, each blade being twisted at a first angle about its longitudinal axis, each blade having its distal ends located a predetermined distance from the axis of rotation, each blade being bent at one or more central locations along the longitudinal axis so the one or more central locations are the same predetermined distance from the axis of rotation as the distal ends, each blade having a foil cross section perpendicular to the axis of rotation for maintaining unidirectional rotation of that blade about the axis of rotation in a fluid flow, and each blade having its longitudinal axis tilted at a second angle with respect to the axis of rotation.

Abstract: An impeller plate of an impeller of a centrifugal pump, particularly a channel impeller pump, for pumping liquids with solid or gaseous admixtures, is provided with at least one wide vane that is displaced toward the impeller drive by a distance D so that the impeller chamber is enlarged by a rearward portion thereof. In addition, the impeller comprises at least one auxiliary vane having a center width at between 25%-75% of the width of the wide vane. This arrangement improves particularly the gas transporting ability of the pump.

Abstract: A venturi receives incoming material through an inlet tube and subjects the material to pulverization. The material, as it undergoes pulverization, is further subject to moisture extraction and drying. An airflow generator, coupled to the venturi, generates a high speed airflow to pull the material through the venturi and into an inlet aperture in the airflow generator. The airflow generator directs the received pulverized material to an outlet where the material may be subsequently separated from the air.

Abstract: A fan comprises an impeller and a motor. The impeller has a hub, a plurality of blades and a plurality of reinforced elements. The blades are disposed around the hub. At least one reinforced element is disposed on the active surfaces of two adjacent blades. The blades and the reinforced elements are integrally formed as a single piece. The motor connects to the impeller for driving it to rotate.

Abstract: A fan assembly for directing fluid flow in a hybrid radial and axial direction includes a backplate having an inner diameter portion and a substantially frusto-conical outer diameter portion positioned about a center axis (CL), a plurality of blades extending from the backplate, and an annular fan shroud positioned adjacent to the plurality of blades and configured for co-rotation therewith. The backplate, the plurality of fan blades and the fan shroud form a fan subassembly, and an overall depth of the fan subassembly is approximately 20-35% of an overall fan subassembly diameter (øD1).

Abstract: An impeller is provided for a blower having a blade (15), a plurality of notches (17) provided at predetermined intervals on a side edge of the blade (15), and a plurality of smooth portions (18) each provided between a pair of the notches (17). Since a transverse vortex discharged from the side edge of the blade (15), and on a large scale, is organized by vertical vortexes formed in the notches (17) on a small scale so as to be segmented into stable transverse vortexes, it becomes possible to reduce aerodynamic noise.

Abstract: A plurality of curved rectangular blades are arranged in a circumferential direction on a periphery of a disc, forming a pipe-like basket shape with an opening on a front side of the disc. Rotation of the disc draws in air from the opening and draws out the air in a centrifugal direction through a space between the blades. The blades are formed of a thick plate part close to the disc and a thin plate part that is thinner than the thick plate part and farther than the thick plate part from the disc. A bulge serving as a boundary between the thick plate part and the thin plate part is formed on a negative pressure surface of the blades, which is of curved convex shape.

Abstract: A wind turbine for generating electricity is configured as a drum with a housing that has adjustable shutters to control the amount of wind reaching the turbine blades. Alternatively, the turbine blades can be pivotably mounted and opened and closed using a cam follower, cam track system to minimize wind exposure to downstream turbine blades.

Abstract: A multi-blade fan includes a spirally-shaped housing which has a bell-mouth orifice on one side, a sucking inlet and an exhausting outlet, an impeller which is placed in a housing and has a plurality of blades supported by a main plate and a lateral plate at both the axial ends, and a motor for driving the impeller. A cross section, cut along vertically with respect to a rotary shaft of the impeller, of each one of the blades has a given shape which allows a main air stream to flow along a back face of each one of blades.

Abstract: An axial-flow fan unit that produces less noise is provided. Blades 19 are exposed from a venturi 29. The shape of each of the blades 19 is so defined that a space formed between at least an inner surface 28a of each of web leg sections 28A to 28C and an edge 19a of each of the blades 19 located in the radially outward direction of the blades 19 expands toward the ends of the web leg sections 28A to 28C (or web bodies 30A to 30C). With this arrangement, noise produced when the blades 19 rotate along the web leg sections 28A to 28C is reduced.

Abstract: An impeller is provided having a first plate, a second plate, a plurality of blades being positioned between and connected to the first and second plates, and at least one brace member having first and second planes positioned between and connected to two blades such that the brace extends generally perpendicular from the first blade and extends from the second blade at an angle.

Abstract: A fan of a heat sink comprising a hub, a plurality of ribs and a set of blades is provided. A distal end of the ribs is connected to circular sidewall of the hub and the set of blades are connected to the primal end of the ribs. The set of blades comprises an outer ring, multiple first blades, a guiding ring connected to the inner side of the first blades and multiple second blades positioned at the inner side of the first blades extending upwards from the top side of the guiding ring. The primal end of the ribs is connected to the guiding ring having an inclined slope extending from the hub towards the outer ring. The first and the second blades are adopted for increasing the air flow area, and thereby increase the air volume and air pressure and the inclined slope of the guiding ring is adopted to smoothly change the flow direction of the sucked air and thereby reduce the resistance to the air flow.

Abstract: A venturi receives incoming material through an inlet tube and subjects the material to pulverization. The material, as it undergoes pulverization, is further subject to moisture extraction and drying. An airflow generator, coupled to the venturi, generates a high speed airflow to pull the material through the venturi and into an inlet aperture in the airflow generator. The airflow generator directs the received pulverized material to an outlet where the material may be subsequently separated from the air.

Abstract: In a centrifugal fan the diameter of the impeller is rendered less than 20 mm, yet by rotating it under rotational conditions in which the centrifugal force along the impeller periphery is 10,000 m/s2 or more, the static pressure that the fan generates is heightened. At the same time, rendering the vane spacing a predetermined width or less reduces noise. Configuring in this way produces a small-scale, high-static-pressure, low-noise fan for cooling electronic devices. Furthermore, by mounting the centrifugal fan on a heatsink having densely arranged heat-dissipating projections a small-scale, high-cooling-capacity, quiet cooling device is realized.

Abstract: A cross flow fan of an indoor unit of, for example, an air conditioner includes a pair of disc-shaped end plates and a plurality of fan blades attached to the end plates in a ring-shaped arrangement. Each of the fan blades has a cross sectional area ratio of Sa/Sb in a range of 1.3 to 1.6, preferably, 1.4 to 1.5, in which Sa is a sectional area of a fan inner peripheral side half portion of the blade and Sb is a sectional area of a fan outer peripheral side half portion of the blade at a time when the fan blade is cut perpendicularly with respect to a longitudinal direction of the fan blade and divided into two sectional areas along a central division line in a blade chord direction.

Abstract: A centrifugal fan includes a hub and an impeller. The impeller is composed of a plurality of blades mounted around an outer circumference of the hub. The paraxial side of the blade forms a backward leaning structure, while the non-paraxial side thereof forms a forward leaning structure. A chamfer structure also can be formed at a paraxial side of each blade to enlarge the air inlet of the fan. Each blade further includes a protrusion, which is located at a side opposite to the inlet and extends toward a center of the hub, to increase the airflow rate through the fan motor. The centrifugal fan further includes an anti-decompression cap connected to an inlet side of the impeller to prevent an axial flow of the intake air from decompression.

Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.