A fan wheel with a hub is centrally supported with respect to a drive and coaxially rotatable with the hub between stops relative to the hub. The fan wheel having fan blades extending radially from the hub are rotatable about their axes in a range delimited by the stops. Overlaying the rotational support between the stops of the hub, a rotational support between the hub and the drive is provided including a planetary drive in operative arrangement with an adjustment control ring of the driven hub. The fan blades are rotatable in the hub about their blade axes, and adjustment of the blade angles of the fan blades via drive connections to the adjustment control ring, which connections operate in a manner superimposed on one another starting from the drive of the fan wheel.

A drive system includes a planetary gear set having first and second rotatable input members connected in driven relation with respective first and second power sources, and a rotatable output member connected in driving relation with a working piece, the first and second rotatable input members being connected in differentially rotatable communication with the output member. The input members are operable to vary the rotation and direction of the output member and the connected working piece. In an aspect, the output member is rotatable about an axis for driving the working piece, and the first and second input members are also rotatable about the axis. In a further aspect, the first and second input members include coupling regions for coupling the first and second power sources on-axis with the drive system. In a further aspect, the second power source is a hydraulic input motor concentric with the first input member.

Currently, there is no efficient mechanism for speed increasing with very high transmission ratio. Therefore, a planetary mechanism is proposed, with two suns (0b, 3b), having teeth numbers: Z.sub.1,Z.sub.4, one stationary (0b) and one (3b) constituting the input of mechanism, a carrier (1a, 1b, 1c, 1d) constituting the output, and a planetic shaft (2b) with two planets (2a, 2c), cooperating with corresponding suns (0b, 3b) and having teeth numbers: Z.sub.2,Z.sub.3, where the term: Z.sub.1/Z.sub.2.Z.sub.3/Z.sub.4 is closest to 1, so the transmission ratio between moving sun (3b) and carrier (1a, 1b, 1c, 1d) is maximum possible. In a specific case, named “Three Successive Integers Mechanism”, this transmission ratio is equal to k.sup.2, where k is integer, easily taking high value. The applications are unlimited, while some are: —wind turbine, —electric assisted bicycle, —energy storage unit of enormous kinetic energy with k.sup.4 times increased moment of inertia, —mechanically driven supercharger for ICE or fuel cell, —robotic articulated arm (as speed reducer).

A method and device is provided for increasing the efficiency of jet drives by recuperating effective power from the propulsion flow. A ducted propeller in the propeller housing, driven by a driving engine via a drive shaft, conveys the fluid for the jet drive out of the interior V.sub.i of a radial turbine. The fluid is accelerated axially and ejected backwards against the direction of travel. This creates thrust. Because the pressure in the interior of the turbine decreases, new fluid from the environment flows directly via the blades of the rotating radial turbine from the outside to the inside, thereby driving them. A guide apparatus is missing. The power of the radial turbine is transmitted via a transmission to the drive shaft of the propeller, which relieves the driving engine and increases the efficiency of the jet drive. The invention is particularly suitable for electric drives.

A fan module with variable pitch blades for a longitudinal axis propulsion assembly. The module includes a rotor through which a rotor shaft runs along the longitudinal axis X and carries the blades of the fan. A system for changing the pitch of the blades includes a mechanism connected to the blades of the fan and a controller acting on the mechanism. The controller has a fixed body and a movable body translatable along the longitudinal axis X relative to the fixed body, and a load transfer bearing arranged between the mechanism and the controller. The fan module includes a power shaft driving the rotor shaft via an epicyclic train speed reducer, the speed reducer including a sun gear connected to the power shaft and a satellite carrier including a fixed annular ferrule secured to a fixed casing. The fixed body of the controller is mounted on the annular ferrule.

Compressors having multi-speed gearboxes are disclosed. The apparatus comprises: a fluid channel to convey a fluid, a compressor fluidly coupled to the fluid channel, a gearbox operatively coupled to the compressor, the gearbox to control the compressor using a first gear ratio and a second gear ratio different from the first gear ratio to vary a flow rate of fluid in the fluid channel, and clutches to vary the gearbox between the first gear ratio and the second gear ratio.

A centrifugal compressor is shown, comprising: an impeller; a rotatably mounted diffuser surrounding the impeller; and a driving arrangement configured to drive the impeller and diffuser to rotate in opposing directions.

A turbofan engine according to an example of the present disclosure includes, among other things, a fan, and an outer housing surrounding the fan to define a bypass flow path, a compressor, a turbine section including a fan drive turbine and a second turbine, an epicyclic gear system with a gear reduction, the fan drive turbine driving the fan through the gear system, and the gear system straddle-mounted by first and second bearings. The fan drive turbine has a first exit area at a first exit point and is rotatable at a first speed. 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 fan module including variable-pitch blades, a fan rotor bearing the blades of the fan, each mounted to pivot about a pitch axis; a fan shaft extending along a longitudinal axis X inside the fan rotor and driving the fan rotor in rotation. A power shaft drives the fan shaft with a planetary gear speed reducer At least a first and a second bearing guide the rotation of the fan rotor, housed inside a lubrication chamber. A system varies the pitch of the fan blades, including a connecting mechanism connected to the blades of the fan and a controller acting on the connecting mechanism. The first bearing is disposed upstream of the speed reducer and the second bearing is disposed downstream of the speed reducer. The fan rotor is connected to the fan shaft by an annular trunnion extending at least along an upstream portion of the lubrication chamber.

A rotary machine includes a cylindrical rotary shaft extending in a direction of an axis, a fastening bolt having a bolt body that extends in a direction of an axis O in the rotary shaft to form fastening portions at both ends, a pair of rotary bodies each having an end portion in the direction of the axis that is fixed to each of the pair of fastening portions to be in contact with an end surface of the rotary shaft in the direction of the axis, and a bolt extension mechanism that temporarily extends the bolt body in the direction of the axis.