A centrifugal fan includes a fan configured to be driven to rotate, and a scroll casing housing the fan. The scroll casing includes a peripheral wall having a volute shape having an inner end of a spiral thereof at a boundary with a tongue portion of the scroll casing. When a portion at the peripheral wall at which a distance between the peripheral wall and a rotation shaft of the fan is minimum is defined as a closest portion, the peripheral wall includes a narrowed portion at which the distance between the peripheral wall and the rotation shaft is reduced from the inner end toward the closest portion in a rotation direction of the fan, and an expanded portion that is formed between the narrowed portion and the closest portion and at which the distance between the peripheral wall and the rotation shaft is increased.

The present disclosure relates to a flow generator.

A flow generator according to an embodiment of the present disclosure may include: a suction portion into which air is suctioned; a fan introducing the air introduced into the suction portion in an axial direction to discharge the air in a radial direction; a fan housing in which the fan is installed and which guides the air discharged from the fan; and a cover surrounding the fan and the fan housing. The fan housing may include: a housing plate supporting the fan; a guide wall protruding from one surface of the housing plate to surround at least a portion of an outer circumference of the fan; a first fan passage provided between at least a portion of the outer circumference of the fan and the guide wall; a second fan passage which is provided between the outer circumference of the fan and the cover and through which the air passing through the first fan passage flows; and a discharge portion located outside an outer surface of the guide wall to discharge the air passing through the second fan passage.

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 includes a body having a main inlet opening and a discharge opening, a motor assembly housed in the body, and an auxiliary inlet opening. The motor assembly includes a case, a motor and a fan. The case has a first opening and a second opening. The motor is housed within the case. The fan is configured to rotate in response to driving of the motor to generate a flow of air passing the main inlet opening, the first opening, the motor, the second opening and the discharge opening in this order. A first space that communicates with the main inlet opening and the first opening of the case is formed within the body. The auxiliary inlet opening is configured to introduce the air from an outside of the body into the first space.

An air handler blower is provided, comprising: a blower wheel having a center plate with one or more openings, a first cylindrical blade assembly extending from a first side of the center plate, the first cylindrical blade assembly containing a plurality of first blades extending from the first side of the center plate and arranged in a circle to define a first cavity, and a second cylindrical blade assembly extending from a second side of the center plate opposite the first side, the second cylindrical blade assembly containing a plurality of second blades extending from the second side of the center plate and arranged in a circle to define a second cavity; a motor located proximate to the first cylindrical blade assembly and configured to rotate the blower wheel; and an axle connecting the motor and the center plate.

A cooling system for optimizing fan air flow performance without compromising acoustic performance is disclosed. At least three fan feature embodiments are disclosed: (1) sloped fan blades, (2) sloped impeller hubs, and (3) inlet flow guidance features. For the first embodiment, fan blades attached to an impeller disc and having leading edges that progressively curve toward a center of the impeller disc. For the second embodiment, the impeller disc is attached to and centered on an impeller hub that has a sloped hub surface that progressively curves toward the fan blades. For the third embodiment, an inlet flow guidance feature is positioned within a region surrounding a fan's inlet promoting smooth passage of air into the fan. In some embodiments, all three fan features are combined.

An impeller includes a backing plate, a rim disposed so as to face the backing plate, and a plurality of blades arranged in a circumferential direction around a virtual rotation axis of the backing plate. Each of the plurality of blades has an inner circumferential end, an outer circumferential end a sirocco blade portion being forward-swept and including the outer circumferential end and having a blade outlet angle of larger than 90 degrees, and a turbo blade portion being swept-back and including the inner circumferential end, a first region located closer to the backing plate than a middle point in an axial direction of the rotation axis, and a second region located closer to the rim than the first region. Each of the plurality of blades is formed such that a blade length in the first region is longer than a blade length in the second region. In the first region and the second region, a ratio of the turbo blade portion in the radial direction is larger than a ratio of the sirocco blade portion in the radial direction.

A heat transfer system (e.g., a heat pump) can include at least a first fin array and at least a first pump disposed in fluid communication with the first fin array and configured to cause a first fluid to flow through the first fin array. The system can include at least a first heat transfer layer attached to and/or in thermal communication with the first fin array. The first heat transfer layer can define a second fluid flow path therein for a second fluid to flow fluidly isolated from the first fluid. The first heat transfer layer and the first fin array can be configured to cause heat transfer between the first fluid and the second fluid.

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.