A compressor according to an embodiment includes: a rotational shaft provided with a compressor impeller on one end side; a rolling bearing device for rotatably supporting the rotational shaft; and a housing for housing the rolling bearing device. The rolling bearing device includes: an inner ring mounted on the rotational shaft; an outer ring supported by the housing with application of a load from the housing in an axial direction of the rotational shaft; a rolling element disposed between the inner ring and the outer ring; an elastic member disposed on an outer circumferential side of the outer ring so as to come into contact with the housing; and a sliding portion disposed on one end side of the outer ring in the axial direction so as to come into contact with the housing.

A linear fan including a fan blade attached a fan frame by a wire spring having a first end attached to the fan blade and a second end attached to the fan frame. The fan blade includes a free end such that the blade oscillates by pivoting on the wire spring. The the wire spring flexes to enable the fan blade to oscillate. The fan includes a motor for driving the oscillation of the fan blade. The motor includes an armature or permanent magnet connected to the fan blade and a stator assembly connected to the fan frame. The stator assembly includes a current carrying coil wrapped around a leg of a stator core. The motor is controlled to vary the direction of the current being carried in the coil to thereby change the direction of the magnetic field created by the stator assembly and cause the fan blade to oscillate.

An aircraft propulsion system comprises a propulsor an electric motor coupled to the propulsor. The electric motor comprises a surface mounted permanent magnet electric machine comprising a rotor mounted radially inward of a stator. A Motor Diameter Ratio (MDR) is defined as an inner diameter (D.sub.stator,in) of the motor stator in metres divided by an outer diameter (D.sub.stator,out) of the motor stator in metres. The MDR of the electric motor stator is within 10% of the value given by the equation:

[00001]${\mathrm{MDR}=0.83\times (\frac{\mathrm{Torq}ue}{L_{active}}\times \frac{1}{U_{\mathrm{fan},\mathrm{tip}}})}^{0.08}$ where: T is the maximum torque rating of the electric motor in kilonewton metres; L.sub.active is the active length of the motor stator in metres; and U.sub.tip is the tip speed of the propulsor at the maximum rated torque of the electric motor in metres per second.

In the described embodiments, the MDR is less than 1.

An electric motor assembly includes an electric motor, a fan assembly coupled to the electric motor and configured to rotate therewith about an axis. The bower assembly also includes a shroud coupled to the electric motor and extending about the fan assembly. The shroud includes a central hub coupled to the electric motor, an inlet ring, and a plurality of arms extending between the central hub and the inlet ring. Each arm of the plurality of arms includes a curved radial portion extending from the central hub and a planar axial portion extending from the radial portion to the inlet ring.

An apparatus includes a pipeline-transport compressor configured to receive, in use, a product stream from a pipeline. The cooler unit is configured to receive, in use, a cooler air intake from the pipeline-transport compressor. This is done in such a way that removal of the cooler air intake by the cooler unit, in use, moves the cool air across the cooler bundles and out through the cooler unit, and cools the pipeline-transport compressor. An air exhaust power generation unit is configured to generate, in use, electric power in response to the cooler unit, in use, urging, at least in part, the cooler air intake toward, at least in part, the air exhaust power generation unit.

A compressor or pump stage is provided. The compressor or pump stage at least comprising a central shaft (8) and one rotor (3), where the axis of rotation of the rotor (3) is the central shaft (8) and where the rotor comprises a number, n, of rows of impellers (5) arranged at an outer perimeter of the rotor with an axial distance between neighbouring rows of impellers (5), where n={2, 3, 4...}.

An e-charger includes a motor case that encases the motor and an outer housing that houses the motor case. The e-charger additionally includes a cooling system with passages cooperatively defined by the outer housing and the motor case. First and second longitudinal passages extend between the first and second ends of the motor, and a second longitudinal passage extends between the second and first ends of the motor. The end passage fluidly connects the first and second longitudinal passage. The cooling system is configured for directing flow of the coolant from the inlet, through the first longitudinal passage in a first longitudinal direction with respect to the axis, through the end passage, and back through the second longitudinal passage in a second longitudinal direction with respect to the axis.

A motor comprising a casing, rotating shaft, magnetic ring, three-phase hollow cup coil winding and insulation end cover, is provided. The casing includes a sleeve and inner core arranged coaxially with the sleeve and air guide plates connected to the sleeve and inner core, the sleeve, inner core and two adjacent air guide plates are surrounded to form an air guide channel, the inner core is provided with a mounting hole, the bearing is installed in the mounting hole, and a rotating shaft passes through the bearing, a magnetic ring is sleeved outside one end of the rotating shaft, the three-phase hollow cup coil winding is sleeved outside the magnetic ring. A rotating gap is set between the three-phase hollow cup coil winding and the magnetic ring, and insulating end cover is installed on the outlet of the sleeve. A wind end fixes the three-phase hollow cup coil winding in the sleeve, and the inner core is provided with heat dissipation holes that are all connected with installation holes.

An air moving device includes a housing member, an impeller assembly, and a nozzle assembly. The nozzle assembly can include one or more angled vanes set an angle with respect to a central axis of the air moving device. The air moving device can output a column of moving air having an oblong and/or rectangular cross-section. A dispersion pattern of the column of moving air upon the floor of an enclosure in which the air moving device is installed can have an oblong and/or rectangular shape. The dimensions of the dispersion pattern may be varied by moving the air moving device toward or away from the floor, and/or by changing the angles of the stator vanes within the nozzle assembly.

A motor assembly has a motor having a rotor and a stator. An impeller is connected to a rotary shaft of the rotor and a housing is disposed between the impeller and the motor and surrounding an upper side of the motor. A diffuser discharges air, which is suctioned by the impeller, along an outer surface of the housing. A heat dissipation cover covers an outer surface of the motor. The heat dissipation cover includes an inner cover spaced apart from the outer surface of the motor and forming an inside-cover flow channel that air flows through and an outer cover having a diameter greater than that of the inner cover and forming an outside-cover flow channel through which air flows along the outer surface thereof.