A speed increaser includes an annular peripheral wall rotatable with a rotation of the low-speed shaft, a high-speed shaft disposed within the peripheral wall and having a rotation axis extending in the same direction as that of the peripheral wall, and three rollers disposed within the peripheral wall and in contact with both the peripheral wall and the high-speed shaft. The three rollers are disposed at different positions along the rotation axis of the high-speed shaft with rotation axes of the three rollers extending in the same direction as the rotation axis of the high-speed shaft, and the rotation axes of the three rollers are spaced in a circumferential direction of the high-speed shaft. The three rollers are disposed so that at least part of contact areas between the high-speed shaft and the rollers is free from overlapping with each other along the rotation axis of the high-speed shaft.

A speed increaser includes a high-speed shaft, an annular peripheral wall surrounding the high-speed shaft and rotatable with a rotation of a low-speed shaft, the peripheral wall having an inner peripheral surface and a projection extending inwardly from the inner peripheral surface in a radial direction of the high-speed shaft, and a roller disposed between the high-speed shaft and the peripheral wall and having an outer peripheral surface that is in contact with both the projection and an outer peripheral surface of the high-speed shaft. A centrifugal compressor includes the speed increaser, an electric motor driving to rotate the low-speed shaft, and an impeller mounted to the high-speed shaft.

A power transmission apparatus has a housing, a first shaft rotatably mounted within the housing, a second shaft rotatably mounted within the housing and extending around at least a portion of the first shaft, a third shaft exterior of the first and second shafts and positioned within the housing, a first transmission connected to the second shaft and to the third shaft such that a rotation of the second shaft causes a rotation of the third shaft, a second transmission connected to the first shaft and to the third shaft such that a rotation of the first shaft applies rotational energy to the third shaft, and a power receiver connected to the third shaft so as to convert the rotational energy of the third shaft into energy or motion.

A gas turbine engine including a drive shaft that drives a propulsor. A frame which supports the drive shaft is a K-frame bearing support. A gear system is connected to the drive shaft. The gear system includes a gear mesh that defines a gear mesh lateral stiffness and a gear mesh transverse. A flexible support supports the gear system that defines a flexible support transverse stiffness and a flexible support lateral stiffness. The flexible support lateral stiffness is less than 8% of the gear mesh lateral stiffness.

Disclosed is an embodiment of a dual seal arrangement for the high-speed shaft of a supercharger with a centrifugal compressor and a mechanical speed step-down transmission to the shaft. A ring located about the shaft splits the rotational speed of the shaft between two seals, so that each seal spins at a speed of roughly half the speed of the shaft. The arrangement can also be used to split the shaft speed between two bearings in the same manner. The high-speed shaft may also have a turbine attached, to form a driven turbocharger.

A gas turbine engine according to an example of the present disclosure includes, among other things, a fan, a compressor section, and a turbine section including a fan drive turbine and a second turbine. The fan drive turbine has a first exit area at a first exit point and is rotatable at a first speed. A mid-turbine frame is positioned intermediate the fan drive turbine and the second turbine, and can include a bearing support. The second turbine has a second exit area at a second exit point and is rotatable at a second speed. A first performance quantity is defined as the product of the first speed squared and the first area. A second performance quantity is defined as the product of the second speed squared and the second area.

A compressor system includes a driving unit having a drive shaft, a plurality of compressors which compress a gas, and a transmission mechanism which increases a speed of a rotation of the drive shaft and transmits the rotation to the plurality of compressors. The transmission mechanism includes a main shaft which rotates together with the drive shaft and a plurality of gear mechanisms which transmit a rotation of the main shaft to the corresponding one compressor. The gear mechanism includes an auxiliary shaft which rotates together with an auxiliary gear meshing with the main gear, a plurality of first gears which rotate together with the auxiliary shaft, an output shaft to which an output gear meshing with the first gear is fixed and which is connected to the compressor, and a first bearing which rotatably supports the auxiliary shaft, and a second bearing which rotatably supports the output shaft.

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.

A transmission system includes planetary gearing with a ring gear, a plurality of planet gears, a carrier, and a sun gear, a forward clutch operatively connected between the ring gear and carrier, a reverse brake operatively connected between the carrier and a rotationally fixed location, and a control subsystem to switch the transmission system between forward and reverse operational modes in the which the ring gear and the sun gear rotate in the same or opposite rotational directions, respectively. A control subsystem actuation stroke can actuate both the forward clutch and the reverse brake based on a common control signal.

A gas turbine engine according to an example of the present disclosure includes, among other things, a fan including a plurality of fan blades rotatable about an engine axis. Each of the fan blades have a leading edge and rotate about a fan blade axis. A method of operating a gas turbine engine is also disclosed.