A negative-pressure balance system for a gearbox of a centrifugal compressor includes the gearbox, a hermetically-sealed low-level oil collecting tank and a U-shaped negative-pressure balance pipe. The gearbox is connected to a respirator, and the back pressure of the respirator is a local ambient atmospheric pressure. The bottom of the gearbox and the low-level oil collecting tank are connected by an oil conduit. An oil demister communicated with the low-level oil collecting tank is mounted at the top of the low-level oil collecting tank. The oil demister at least includes a ventilation device. The respirator is communicated with a front-end lubricating point in the gearbox. One end of the U-shaped negative-pressure balance pipe is communicated with the respirator, and the other end of the U-shaped negative-pressure balance pipe is communicated with a rear-end lubricating point in the gearbox.

A fan drive gear system for a turbofan engine includes a geared architecture and a gear controller supporting the geared architecture and controlling rotation of the geared architecture relative a static structure.

A pressure relief passage includes a first pressure relief passage and a second pressure relief passage. A pressure relief hole is provided in an upper part of the first pressure relief passage in the direction of gravitational force. The second pressure relief passage merges with the first pressure relief passage to form a merging portion. The cross-sectional flow area of a stagnation portion, which is the maximum cross-sectional flow area of the second pressure relief passage, is smaller than the cross-sectional flow area of a connection passage, which is the minimum cross-sectional flow area of the first pressure relief passage.

A ceiling fan includes a transmission unit for decoration. The transmission unit includes a base seat connected to a stator axle of a rotating motor for driving a blade module, a sun gear disposed rotatably on the base seat, a driving motor disposed on the base seat, and a first planet gear connected to the driving motor and meshing with the sun gear. The driving motor drives the first planet gear to rotate the sun gear. The sun and first planet gears are exposed at a bottom side of the base seat so as to be externally visible.

A centrifugal compressor includes a partition wall that is arranged between a ring member and the bottom of a main body in a speed-increaser chamber. The centrifugal compressor further includes an introduction passage that guides oil in a stirring region to a storage region. The stirring region includes a region between the partition wall and the ring member in the speed-increaser chamber. The storage region includes a region between the partition wall and the bottom of the main body in the speed-increaser chamber. The oil that has been stirred by rotation of the ring member collides the inner circumferential surface of a speed increaser housing before flowing toward the partition wall. The oil is then guided to the storage region via the introduction passage. Since the oil stored in the storage region is unlikely to be stirred by rotation of the ring member, only a small amount of oil is stirred by the ring member.

A gas turbine engine for an aircraft includes an engine core including an engine core, a turbine, a compressor, and a core shaft connecting the turbine to the compressor, the turbine comprising a lowest pressure rotor stage, the turbine having a turbine diameter at the lowest pressure rotor stage. A fan located upstream of the engine core, the fan comprising a plurality of fan blades extending from a hub, the hub and fan blades together defining a fan face having a fan face area and a fan tip radius. A ratio of the fan tip radius to the turbine diameter at the lowest pressure rotor stage is in the range from 1.2 to 2.0.

This supercharging device is provided with an impeller having a shaft, a motor generator configured so as to rotate the impeller to perform supercharging, a planetary gear mechanism, and a restricting mechanism configured so as to restrict the rotation of the impeller. The planetary gear mechanism has a sun gear to which the shaft is linked, a ring gear configured so as to rotate by means of motive power from an engine, a plurality of planetary gears, and a carrier linked to the plurality of planetary gears. The carrier has a cylinder part through which the shaft passes. The motor generator has a rotor integrated with the outer peripheral surface of the cylinder part, and a stator disposed on the radially outward side of the rotor.

A gas turbine engine includes a fan drive turbine driving a fan rotor through a main gear reduction. A primary lubricant system supplies lubricant to the main gear reduction. An auxiliary oil pump supplies oil to the main gear reduction. An auxiliary pump epicyclic gear train drives the auxiliary pump when the fan rotor is rotating in either direction. The main gear reduction is separate from the auxiliary pump epicyclic gear train.

A rotary machine includes a plurality of shafts that extend in an axial direction, in which an axis extends, around the axis, are disposed such that at least parts of positions in the axial direction of the plurality of shafts overlap each other, and are rotatable relative to each other around the axis; a plurality of seal members that are disposed at intervals in the axial direction to seal gaps between the plurality of shafts in a radial direction with respect to the axis; and a seal gas supply unit configured to supply a seal gas from outside to a space surrounded by the plurality of shafts and the plurality of seal members.

The present invention is directed to a load bearing direct-drive system and a variable process control system for efficiently managing the operation of fans in a cooling system such as a wet-cooling tower, air-cooled heat exchanger (ACHE), HVAC system, blowers and centrifugal blowers, mechanical towers or chiller systems. In one embodiment, the load bearing direct-drive system comprises a load bearing torque multiplier device having an output rotatable shaft connected to a fan, and a load bearing motor comprising a rotatable shaft that drives the load bearing torque multiplier device.