An airflow-doubling vane structure includes an axle, an inner vane unit, and an outer vane unit. The inner vane unit includes a plurality of vanes provided around a center defined by the axle and can be rotated along with the axle. The vanes of the inner vane unit are centrifugal vanes. The outer vane unit includes a plurality of vanes provided around the center defined by the axle and around the inner vane unit and can be rotated along with the axle. The vanes of the outer vane unit are axial-flow vanes and extend a certain radial distance from the vanes of the inner vane unit.

A radial impeller having a cover plate with an inlet opening and a support plate, the plates being connected to one another by means of a vane ring having multiple vanes. The vanes each have two side edges opposite one another, one of which is connected to the cover plate and the other to the support plate. The side edges each extend between a vane inlet edge and a vane outlet edge which is opposite in a circumferential direction of the impeller. The vanes are each designed as a hollow profile and have two vane halves delimiting a cavity between them which are applied to one another and are each connected to one another in the region of the vane inlet edge and the vane outlet edge by means of a welded connection.

A centrifugal heat dissipation fan including a housing and an impeller is provided. The housing has at least one flow inlet. The impeller assembled in the housing and rotating about an axial direction includes a hub and a plurality blades disposed around the hub. The flow inlet is located in the axial direction and faces the hub. Each of the blades has a wing tab next to the flow inlet, and the wing tab extends from a main surface of the blade to another blade. The wing tab has an inclined surface facing toward a periphery of the flow inlet along a radial direction of the impeller.

A motor-fan assembly includes an assembly housing which supports a motor assembly, a working fan assembly which includes a working fan rotated by the motor assembly which draws in and exhausts working air, and a cooling fan assembly which includes a cooling fan rotated by the motor assembly which draws in and exhausts cooling air. The assembly housing includes a motor vent cover associated with the cooling fan assembly, wherein the motor vent cover further includes a sidewall with at least one vent hole therethrough and at least one socket aligned with the at least one vent hole. The assembly also includes a body having a tube opening extending therethrough, and an inner facing surface with at least one tail receivable in the at least one socket so that the at least one vent hole is contiguous with the tube opening.

A motor including a rotating portion that is rotatable about a center axis that extends vertically and a stationary portion that rotatably supports the rotating portion. The stationary portion includes a stator facing at least a portion of the rotating portion in a radial direction, a base disposed axially below the stator, and a resin portion covering at least a portion of the stator, connecting the stator and the base. The base includes a recessed portion that is recessed downward in an axial direction and that accommodates at least a portion of the resin portion. The recessed portion includes an inner peripheral surface provided with an upper wall portion disposed axially above a portion of the resin portion.

The present disclosure provides a fan including a hub and multiple fan blades coupled to the hub and located circumferentially along the hub. Each fan blade extends between a root and a tip edge thereof and includes a first portion inclined at a first predefined angle with respect to the hub. The first portion induces an axial flow of air. The fan blade also includes a second portion extending from the first portion and between a leading edge and a trailing edge of the fan blade. The second portion is embodied as an airfoil defining an angle of attack to induce a radial inward flow of air. A radius of curvature of a trailing edge segment of the second portion is less than a radius of curvature of a leading edge segment of the second portion.

The CPAP device includes a blower. The blower includes a motor and a blower fan rotatable by the motor. The motor includes a stator assembly including a plurality of coils arranged in a circumferential direction, and a rotor assembly including a permanent magnet and disposed in an inner side portion of the stator assembly in a radial direction. An output shaft is inserted into the rotor assembly. The output shaft rotates together with the rotor assembly. The blower fan is fixed to a tip end of one side of the output shaft. Part of the output shaft is inserted into an insertion hole provided at a center of the base. A plain bearing is interposed between an inner peripheral surface of the insertion hole and an outer peripheral surface of the output shaft.

A fan unit that forms part of a gases supply unit used as part of a breathing assistance system for providing heated gases to a user. The fan has an impeller surrounded by an upwardly sloped surface to facilitate improved airflow performance under surge conditions.

A centrifugal blower includes a motor located in a motor housing, an impeller, and a volute. The volute directly contacts the motor housing such that the volute is configured to actively cool the motor during operation.

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.