A bladeless fan with multiple air ducts is disclosed. The bladeless fan has a fan housing, a control system arranged in the fan housing, a blower system connected with the control system, an intermediate air duct communicating with the blower system and a rotation component connected with the control system. The intermediate air duct is provided with a side air duct at its both sides, the rotation component is connected with the side air duct to drive the side air duct to fold and unfold with the intermediate air duct as a center shaft. The side air duct is driven by the rotation component to fold and unfold with the intermediate air duct as a center shaft. The fold and unfold of the side air duct can achieve different effects, satisfy the user's requirement and improve the user experience.

A centrifugal or diagonal impeller has impeller blades (4) that are curved in the circumferential direction about an axis of rotation and are formed from a single-layer sheet metal. Each blade (4) has a suction side (11) and a pressure side (12) as well as a blade leading edge (5) and a blade trailing edge (6). At least the blade leading edge (5) of the impeller blades (4) adjacent to their suction side (11) have a geometric edge modification in the form of a rounding (7) over a predetermined partial length of a blade thickness (SD) of the impeller blades (4).

Embodiments of the inventive technology include a centrifugal fan having a damper repositionable between a closed position and a fully seated open position, and a magnetic coupler that serves to fully seat that damper it its open configuration, so as to prevent undesired effects such as slippage and/or rocking of that damper relative to rotatable componentry against which it is pressed, during operation of the fan. The coupler may be configured so that the damper may decouple from rotatable componentry, e.g., upon a certain reverse pressure differential, and translate to a closed position.

In an embodiment, a blower for a heating, ventilation, and air conditioning system includes a blower wheel and a housing. The blower wheel includes backward-curved blades configured to rotate in a rotational plane. The housing forms an at least hexagonal cross- section around at least a portion of the rotational plane, where the blower wheel is positioned within the housing such that there exists a first distance and a second distance. The first distance is measured radially outward from a center of the blower wheel to a first side of the at least hexagonal cross-section. The second distance is measured radially outward from the center of the blower wheel to a second side of the at least hexagonal cross-section. The second distance forms a an acute angle with the first distance. The first distance and the second distance are unequal and less than a diameter of the blower wheel.

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.

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.

A centrifugal fan includes an impeller with a base expanded radially, vanes arranged circumferentially, extending from a radially inner side to a radially outer side, and ends thereof at one axial side being connected to the base, and a ring portion connecting ends of the vanes at the other axial side. The vanes include first vanes and second vanes, when viewed axially, the lengths of the second vanes are larger than the lengths of the first vanes, the first vanes and the second vanes are circumferentially arranged alternatingly. Gaps are provided between radially outer ends of the first vanes and the second vanes that are circumferentially adjacent to each other, and sizes of circumferentially adjacent ones of the gaps are different from each other.

To enhance responsivity of temperature sensor detecting an engine temperature. A temperature sensor component 40 includes a metal washer 42. The temperature sensor component 40 transfers the engine temperature to a sensor body 46 via the heat transfer washer 42. A cylinder portion 8 of a cylinder block 64 has two bosses 30. The washer 42 of the temperature sensor component 40 is fixed to the boss 30 together with the electronic control unit 20.

A fan module includes a first casing, a driving motor disposed in the first casing, a first rotor connected to the first driving motor, a second casing, a second rotor pivotally configured in the second casing, at least one guiding member and a shift apparatus connected to the first casing and the second casing, the first rotor includes a first rotating shaft and a plurality of first blades, the second rotor includes a second rotating shaft and a plurality of second blades, the guiding member is disposed on the first blade and the second blade. The whole height of the blade is adjusted by adjusting the distance between the two group blades, then the efficiency of the fan is improved effectively to optimize the noise level and the air flow.

The present disclosure provides a portable blowing device configured for being worn around a neck of a human body, the portable blowing device includes two parts and two first fans. Each first part defines an airflow channel therein and includes an inner side wall, an outer side wall, and a top side wall connected between the inner side wall and the outer side wall. Each fan is received in one corresponding part and configured for generating an airflow to flow through the airflow channel defined therein. At least a portion of each of the two top side walls includes an inclined surface. Each of the parts defines at least one first air inlet and at least one first air outlet communicated with the at least one first air inlet and the airflow channel, and each of the first air outlets is defined in one corresponding inclined surface.