A fan frame assembly includes a first fan frame and a second fan frame. The first fan frame includes a first annular wall part and a plurality of first engagement parts connected to the first annular wall part. The second fan frame includes a second annular wall part and a plurality of second engagement parts connected to the second annular wall part. Each of the first engagement parts has a positioning structure extending along an axial direction of the first annular wall part, and each of the second engagement parts has a positioning structure extending along the axial direction of the first annular wall part. when the first engagement parts and the second engagement parts are respectively engaged with each other, the positioning structures of the second engagement parts are positioned by the positioning structures of the first engagement parts.

A quick-release mechanism for fan includes a first lateral cover, a second lateral cover, a latch member, a handle, and a pushing member. The first lateral cover has a slot hole. The latch member extends from the slot hole and has an engaging block and an actuation portion connected to the engaging block. The handle has a first pivot end and a second pivot end pivotally connected to the first lateral cover and the second lateral cover, respectively. The handle is movable between a first position and a second position. The pushing member is disposed at the first pivot end. When the handle is at the first position, the actuation portion moves toward the first lateral cover. When the handle is at the second position, the pushing member pushes the actuation portion to move toward a direction away from the inner surface.

A fan inspection jig includes a jig assembly having multiple spring abutment pillars for holding two sides of a fan (or a series fan) to make the fan or the series fan positioned in a suspending position. A vibration sensor is disposed in at least one of the spring abutment pillars of two sides of the fan for measuring a vibration signal of the fan in operation.

An axial fan includes a housing, an upper motor, and a lower motor. The housing includes an upper housing and a lower housing. A lower peripheral wall of the lower housing includes first engaging portions and lower protruding pieces. The lower protruding pieces oppose the first engaging portions in an axial direction and protrude axially upward from an axially upper surface. An upper peripheral wall of the upper housing includes upper engaging claws and upper notch grooves. The upper engaging claws extend axially downward from an axially lower surface, and include a second engaging portion that engages with the first engaging portion in a lower end portion. The upper notch grooves are notched axially upward from the axially lower surface radially inward of the upper engaging claw. At least a portion of the lower protruding pieces is located in the upper notch grooves.

The aspects of the disclosed embodiments are directed to a fan for displacing a fluid, which fan includes a rotor rotating around its axis of rotation and surfaces, such as blades, forming a flow when the rotor rotates. The rotor is arranged to displace fluid simultaneously with at least two different flows (F1, F2).

Disclosed are a fan apparatus and an air conditioner outdoor unit. The fan apparatus includes: a first wind wheel and a second wind wheel, axially arranged in an interval. A spacing S1 between the first wind wheel and the second wind wheel satisfies S1<(H1+H2)/2, where H1 is a length of the first wind wheel along the axial direction, and H2 is a length of the second wheel along the axial direction.

An illustrative example embodiment of a transport refrigeration system includes an evaporator air management system having an evaporator heat exchanger and an air passage downstream of the evaporator heat exchanger. A two-stage fan assembly within the air passage includes a first fan stage having a first fan rotor, a first motor associated with the first fan rotor for selectively causing the first fan rotor to rotate in a first direction about a fan axis, a second fan stage having a second fan rotor in series with the first fan rotor, and a second motor associated with the second fan rotor for selectively causing the second fan to rotate in a second, opposite direction about the fan axis. The first and second fan stages draw air across the evaporator heat exchanger and through the air passage.

A counter rotating axial air moving device structure is disclosed. The rear rotor includes a rear hub and rear blades, and a pitch angle of each of the rear blades increases gradually in a direction away from the rear hub. The front rotor, the rear rotor and the stator component are stacked with each other. The ratio of the thickness to the diameter is equal to or greater than about 0.25 and equal to or less than about 0.8. Therefore, a better performance curve is obtained, and the vibration and noise are avoided.

An aircraft having a frame assembly that supports a compressor having an outer shell that defines front and rear nozzle ports with rotatable nozzles for selectable vertical or horizontal thrust. The inner shell and the outer shell define an intake gap therebetween such as an annulus. A first fan unit within the inner shell and is configured to exhaust air through the front nozzle ports. A second fan unit within the outer shell intakes air through the intake gap and exhausts air through the rear nozzle ports. The fan units are preferably connected to one another via a drive shaft that is surrounded by a streamlining tube. The fan units each include a plurality of fans having stators therebetween. The stators have a plurality of stator arms with a wing structure pivotally attached to the trailing edge for angling air flow from a front to a rear fan.

A counter-rotating axial air moving device includes a front rotor and a rear rotor. The front rotor includes a front hub and a plurality of front blades, and the number of the front blades is equal to or greater than 7 and equal to or less than 11. The rear rotor is disposed on the downstream side of the front rotor. The rear rotor includes a rear hub and a plurality of rear blades, and the number of the rear blades is equal to or greater than 6 and equal to or less than 10. The front rotor and the rear rotor are stacked with each other with a total thickness and a diameter. The ratio of the total thickness to the diameter is equal to or more than 0.91 and equal to or less than 1.5.