The vacuum suctioning unit of the present invention includes: a cover provided with an air entrance; an impeller for circulating air that enters the air entrance; a motor provided with a shaft connected to the impeller; a guide device for guiding the flow of air that exits an exit of the impeller; and a motor housing that houses the motor and is provided with an air exit. The guide device includes: a guide body disposed below the impeller; a first guide vane formed on a side surface of the guide body and guiding air discharged from the impeller; and a second guide vane formed on the bottom surface of the guide body and connected to the first guide vane to guide air that is moved by the first guide vane. The entrance angle of the first guide vane is within the range of 10 to 27 degrees.

An electric blower includes a motor, a first rotor blade provided on one end side of the motor in an axial direction, a second rotor blade provided on another side of the motor opposite to the first rotor blade in the axial direction, and a first stator blade provided to face the first rotor blade.

The present invention relates to a blower, the blower according to an embodiment of the present invention comprising: a lower case having a suction hole formed therein through which air is introduced; an upper case arranged on the upper side of the lower case and having a discharge hole formed therein through which air is discharged; and a fan arranged in the lower case and including a plurality of blades. Each of the plurality of blades includes a plurality of airfoils respectively extending along different camber lines from one another, and a leading edge of connecting the leading ends of the plurality of airfoils. Entrance angles formed by the respective camber lines of the plurality of airfoils and the rotation directions of the blades are different from one another. Thus, due to the curved shape of the leading edge and the design of a recessed notch, a flow separating from the leading edge is reduced, and thus, there is an advantage in that air volume performance is improved.

The invention relates to a ventilation device for a vehicle ventilation, heating and/or air-conditioning system, including at least one housing that includes at least one wall defining an inner volume in which at least one radial propeller capable of being rotated and at least one guide member are received, the radial propeller and the guide member being configured to generate an air flow having a general direction parallel to an axis of rotation of the radial propeller between an air inlet of the radial propeller and an air outlet formed in the wall of the housing of the ventilation device, at least a part of the wall of the housing being configured to straighten the air flow at the outlet of the radial propeller. The guide member is configured to direct the air flow towards the axis of rotation of the radial propeller.

An impeller comprising a hub, a shroud, a plurality of blades, and circumferential outlet. The hub extends to an outer diameter and is rotatable about a longitudinal axis. The should defines an inlet aperture, extends to the outer diameter, and is offset from the hub along the longitudinal axis to define a passageway between the hub and the shroud. The plurality of blades are located between the hub and the shroud, the blades dividing the passageway into a plurality of passages between each of the plurality of blades. The circumferential outlet is between the hub and the shroud adjacent the outer diameter. Airflow is generated by the plurality of blades, the airflow passing along a flow path within each of the plurality of passages. A size of a cross-sectional area perpendicular to the flow path increases linearly along the flow path from the inlet aperture to the circumferential outlet.

A turbo compressor includes a housing with a refrigerant suction hole, through which a refrigerant is introduced, at a front portion thereof, and a motor case defining an accommodation space. The accommodation space includes a rotation shaft extending in a front-rear direction and a motor that is configured to rotate the rotation shaft. A first impeller is coupled to one end of the rotation shaft and a second impeller is coupled to the other end of the rotation shaft. The first impeller is configured to primarily compress the refrigerant introduced into the refrigerant suction hole. A connection passage, that surrounds the motor case extends backward from an outlet of the first impeller. The second impeller is configured to secondarily compress the refrigerant introduced through the connection passage.

The invention relates to a housing, wherein the housing has a cover disk having a cylindrical wall and a central receptacle with a hub for supporting a fan having a diagonal fan wheel, wherein a plurality of three-dimensionally curved air guide vanes (S) are arranged about the hub, characterized in that the air guide vanes (S) are materially connected to the cylindrical wall and as a result, the housing is produced in one working step.

A blower may include a first case and a second case provided above the first case and having a first tower and a second tower that have a passage therebetween. A display assembly is received in the second case at a position that does not interfere with air flowing in the passage. An inner surface of the second tower and an outer surface of a diffuser define a space in which the display assembly is received.

A heating, ventilation, and/or air conditioning (HVAC) system includes a compressor having an impeller configured to rotate and drive a working fluid through a working fluid circuit of the HVAC system in an active operating mode. The HVAC system further includes a controller configured to, in response to receiving an input indicative of a transition to operate in an inactive operating mode, suspend the active operating mode by interrupting a supply of power to the compressor, adjust pre-rotation vanes of the compressor, a variable geometry diffuser of the compressor to a first position, or both to enable a backflow of the working fluid through the compressor for a first interval of time, and, after the first interval of time has elapsed, adjust the pre-rotation vanes, the variable geometry diffuser, or both to a second position to block the backflow of the working fluid through the compressor.

A fan is provided, including: a body including a fan motor unit, which includes an impeller, a motor and an air-output three-way seat and a nozzle connected to an air outlet of the body, wherein the nozzle receives the airflow from the body and emit the airflow, the nozzle includes a nozzle body in a shape of half a frame; the air-output three-way seat includes at least one air inlet, a first air outlet, a second air outlet, and an air-splitting wall body for splitting the airflow passing through the air inlet and then guiding the airflow to the first air outlet and the second air outlet, respectively. The fan changes the moving direction of the airflow therein, and decreases the entire height and volume.