Systems and methods are provided for cooling electronics and rear end stator windings in an alternator. The system includes an alternator having a rotor assembly, stator assembly, and dual-sided fan disposed in a housing. The housing includes a drive end, rear end, and sides. The rotor assembly includes drive end and rear end poles. The stator assembly surrounds the poles and includes drive end and rear end stator windings. The dual-sided fan is mounted to the rotor assembly adjacent the rear end poles within the housing. The dual-sided fan includes a separating wall, drive end blade set, and rear end blade set. The drive end blade set extends from a first side of the separating wall and at least partially faces the drive end. The rear end blade set extends from a second side of the separating wall and at least partially faces the rear end.

A centrifugal fan impeller structure includes a hub and a blade body set. The hub has an extension section. The blade body set has multiple blade bodies. The blade bodies outward extend from the extension section of the hub. Each two adjacent blade bodies define therebetween a flow way, an air outlet and an air inlet. The air outlet and the air inlet are respectively positioned at two ends of the flow way in communication with the flow way. The air outlets are arranged at unequal intervals so as to greatly reduce noise in operation.

A blower assembly includes a blower housing and a fan wheel mounted within the blower housing and being rotatable about an axis of rotation. The fan wheel includes a support disk positioned near a center of the fan wheel. A first wheel portion having a first plurality of impeller blades is positioned adjacent a first side of the support disk. A second wheel portion having a second plurality of impeller blades is positioned adjacent a second side of the support disk. The first wheel portion and the second wheel portion are asymmetrical about a plane oriented perpendicular to the axis of rotation and intersecting the support disk.

A fan apparatus is disclosed having a first fan and a second fan, both of which are centrifugal fans. Impellers of the first fan and the second fan can be located adjacent one another and adapted to rotate in opposite directions. A first outlet opening (ot1) provided on a housing of the first fan can be located relative to a second outlet opening (ot2) provided on a housing of the second fan such that a flow pattern of the first fan overlaps at least partially with a flow pattern of the second fan when viewed from a direction of a rotation axis of an impeller of the first fan.

A portable blowing device configured for being worn around a neck of a human body, includes two arms each defining an airflow channel therein; and fans received in the arms respectively. The arm includes an inner side wall close to the neck and an outer side wall connected to the inner side wall. The arm includes an air inlet and an air outlet in communication with the airflow channel respectively. The air inlet is arranged at the inner side wall and/or the outer side wall. The fan is configured to generate an airflow passing through the air inlet, the airflow channel and the air outlet in sequence.

A motor assembly having a rotational axis includes a motor housing comprising a plurality of cooling openings extending therethrough and defining a chamber. The motor assembly also includes a stator fixedly coupled to the motor housing and positioned within the chamber. A rotor is coupled to at least one of the motor housing and the stator, wherein the rotor is configured to rotate about the axis and is positioned within the chamber. The motor assembly includes a fan having a first inlet side on a first axial side of the fan and a second inlet side on a second, opposing, axial side of the fan. The fan is configured to draw cooling air in a first direction through the at least one cooling opening into the first inlet side, and the fan is also configured to draw cooling air in a second, opposite direction into the second inlet side.

A turbo fan includes a main plate rotationally driven, and a plurality of blade portions arranged at intervals in a circumferential direction on the main plate. The plurality of blade portions include a plurality of first blade portions arranged on one of plate surfaces of the main plate, and a plurality of second blade portions arranged on another plate surface of the main plate. In a case where, in each of the plurality of first blade portions, a length of a virtual straight line connecting a first inner peripheral end part positioned on a rotary shaft side in a radial direction of the main plate and a first outer peripheral end part positioned on an outer edge side of the main plate is defined as a first chord length, and in each of the plurality of second blade portions, a length of a virtual straight line connecting a second inner peripheral end part positioned on the rotary shaft side in the radial direction of the main plate and a second outer peripheral end part positioned on the outer edge side of the main plate is defined as a second chord length, the first chord length and the second chord length are not equal to each other at positions separated by a same distance from the main plate in the axial direction of the rotary shaft.

A centrifugal fan includes: an impeller having a back plate; and a scroll casing including a peripheral wall a first side wall facing a virtual extension of the back plate and an inner end portion of the volute shape of the scroll casing, an expanded portion, and a first edge end portion being an end of a first edge defining the discharge port, of the first side wall, are arranged in a named order in the rotation direction, the first edge end portion being farther from the rotation shaft than an other end of the first edge and distance L1≥distance LM≥distance LS>is satisfied where LS is a distance between the first side wall at the inner end portion of the volute shape and the virtual extension of the back plate, LM is a distance between the first side wall at the expanded portion and the virtual extension of the back plate, the expanded portion being a portion at which the distance between the first side wall and the virtual extension of the back plate is larger than LS, and L1 is a distance between the first side wall at the first edge end portion and the virtual extension of the back plate.

A blower assembly includes a blower shelf having a first support channel. The blower shelf includes a guide bracket coupled to the blower shelf to form a second support channel. A blower housing having a flange is configured to extend into the first support channel and the second support channel. The blower assembly includes a control mounting panel configured to couple to the blower housing and having a tab extending therefrom. The flange of the blower housing is configured to engage with the first support channel and the second support channel during transition of the blower housing along a first direction and into an installed configuration of the blower housing and during transition of the blower housing along a second direction, opposite the first direction, and into an uninstalled configuration of the blower housing. The tab abuts the guide bracket in the installed configuration.

A blower assembly including a scroll having a first airflow deflector nose and a second airflow deflector nose, which are offset relative to each other about a circumference of the scroll. A rotor is housed within the scroll. The first airflow deflector nose is configured to deflect airflow generated by the rotor out of the scroll to a first outlet of the blower assembly. The second airflow deflector nose is configured to deflect airflow generated by the rotor out of the scroll to a second outlet of the blower assembly.