A blower for an HVAC system, the blower includes a housing with an intake and an outlet, a fan or blower wheel disposed within the housing and configured to draw air into the housing via the intake and to exhaust air from the housing through the outlet, and an adjustable cutoff plate configured to be moved between at least a first position defining a first cutoff angle and a second position defining a second cutoff angle.

Devices and methods for reducing noise of a blower reduce and/or substantially block the exchange of gas within the blower housing from an area of a generally high-velocity flow of gas to an area of a comparatively lower-velocity flow of gas, for example near the outlet of the blower housing.

A pump unit includes a pump housing having a valve assembly positioned on a wall thereof and adapted to be coupled to an inflatable device, and an air control assembly that is housed inside the pump housing. The air control assembly includes an impeller section that houses an impeller, and has an air inlet and an air outlet. The air control assembly further includes a motor housing that houses a motor, the motor housing having an air vent that communicates the interior of the motor housing with the air inlet and the air outlet, and a vent opening that communicates the interior of the motor housing to the environment. The air outlet is aligned with the valve assembly when the pump unit is operated in the inflation mode, and the air inlet is aligned with the valve assembly when the pump unit is operated in the deflation mode.

A centrifugal fan and a dryer, where the centrifugal fan includes a shell, a driving mechanism, an impeller and a volute tongue arranged in the shell, the driving mechanism is connected with the tongue and can drive the tongue to rotate between a first limit position and a second limit position, the tongue includes a first volute tongue part and a second volute tongue part; when the tongue is located at the first limit position and the impeller rotates forwards, the first tongue part abuts against the inner wall of one side of the shell in a sealed mode, the second tongue part can cut the air blown by the impeller, and when the tongue is located at the second limit position and the impeller rotates reversely, the first tongue part can cut air blown by the impeller.

A centrifugal fan and a clothing dryer. The centrifugal fan includes a housing as well as an impeller and a worm tongue disposed in the housing. The housing has an air inlet and an air outlet. The volute tongue includes a first volute tongue and a second volute tongue that are stacked and staggered. The first volute tongue cuts the air blown from the impeller and guide the air to the air outlet when the impeller rotates forward. The second volute tongue cuts the air blown from the impeller and guide the air to the air outlet when the impeller rotates backward. When the impeller rotates, the first volute tongue or the second volute tongue can cut the air blown from the impeller and guide the air to the air outlet, so that the centrifugal fan can blow out air when the impeller rotates forward and backward.

In a compressor, a scroll includes a winding end portion, a discharge potion connected to the winding end portion, a winding start portion connected to the discharge potion, and a flow passage inner surface and when a projection plane is assumed for the scroll in a case in which a viewing point is located on a rotation axis of a compressor impeller and on a fluid suction side, and the flow passage inner surface on the projection plane includes a curved protrusion portion protruding outward in relation to the reference line.

The disclosure relates to an asymmetrical double-outlet blower, including an upper case, a lower case and an impeller. The upper case includes an inlet. The lower case and the upper case are assembled to form a housing having an accommodation space, and form a first outlet and a second outlet. The accommodation space is in fluid communication with the first outlet, the second outlet and the inlet. The first outlet and the second outlet are disposed on a lateral periphery of the housing and face two opposite directions, respectively. An opening cross-sectional area of the first outlet is less than an opening cross-sectional area of the second outlet. The impeller is accommodated within the accommodation space of the housing, spatially corresponding to the inlet, and rotated around a rotation axis. An airflow is inhaled through the inlet and transported to the first outlet and the second outlet, respectively.

A centrifugal blower assembly includes a scroll wall, a pair of opposing sidewalls, and an adjustable cutoff plate. The scroll wall is positioned between the pair of opposing sidewalls such that the scroll wall and opposing sidewalls together define a blower chamber and a blower outlet. The scroll wall extends circumferentially between a cutoff point to an end point and defines a cutout extending circumferentially from the cutoff point. The scroll wall, the pair of opposing sidewalls, and the cutoff point define a blower outlet. The blower outlet defines a blower outlet area. The adjustable cutoff plate is adjustably positioned within the cutout to define a notch defining a notch area. The notch area and the blower outlet area define a total blower outlet area.

A housing of a centrifugal fan, a centrifugal fan and a clothes dryer; a layered structure is provided within an air duct of the housing, and the layered structure is configured to be able to divide at least a part of the air duct into at least two air layers, the width of an air layer close to a strong air end being greater than the width of an air layer close to a weak air end. Also disclosed are a centrifugal fan having the housing and a clothes dryer having the centrifugal fan. By the layered structure being disposed within the air duct, the air duct is divided into at least two air layers, and the width of the wind layer close to the strong wind end is greater than the width of the wind layer close to the weak wind end.

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.