A transmission structure of a helicopter according to one aspect is a transmission structure that transmits power from a prime mover to a rotary wing in the helicopter. The transmission structure includes: a housing; an input shaft that transmits the power of the prime mover to a gear arranged in the housing; a bearing supporting the input shaft in the housing such that the input shaft is rotatable, the bearing including an annular inner ring that holds the input shaft, an annular outer ring that is arranged outside the inner ring in a radial direction and fixed to the housing, and rolling elements sandwiched between the inner ring and the outer ring; and a sleeve that is sandwiched between an inner peripheral surface of the inner ring and the input shaft and is lower in heat conductivity than the inner ring and the input shaft.

A vibration-reducing portal box assembly for mounting a wheel of an off-road vehicle includes a housing with a receptacle adapted to receive a stock axle shaft of an off-road vehicle, an output shaft operably connectable to a stock axle received in the housing and effective to rotate upon rotation of said stock axle, and a wheel hub having a central opening adapted to receive said output shaft, and adapted to turn a wheel mounted to said wheel hub upon rotation of said output shaft. The output shaft has a tapered portion connecting its proximal end to its distal end. The wheel hub has a tapered portion adapted to matingly receive the tapered portion of the output shaft. The output shaft may be connected to the stock axle shaft by a geared linking mechanism.

Device for securing an orientation of photovoltaic panels includes a stem for supporting an array assembly of photovoltaic panels for producing an electrical current when exposed to sunlight. The array assembly also includes eye blades positioned on a side opposite to a photovoltaic panel carrying side. The device further includes a joint interconnecting the stem and the eye blades of the array assembly. The joint includes a hollow horizontal conduit and a bolting mechanism for adjustably coupling the eye blades to lateral ends of the horizontal conduit. A side of each eye blade facing the horizontal conduit carries an eye blade gear that cooperatively meshes with a conduit gear carried at or near a lateral end of the horizontal conduit to secure the array assembly at a predetermined angle relative to a longitudinal axis passing through the stem.

A gas turbine engine for an aircraft configured with an engine core that has a turbine, a compressor, and a core shaft connecting the turbine to the compressor. A fan located upstream of the engine core, that has a plurality of fan blades. A gearbox arranged to receive an input from the core shaft and to output to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox being an epicyclic gearbox having a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The gearbox having an overall gear mesh stiffness, and wherein the overall gear mesh stiffness of the gearbox is greater than or equal to 1.05×10.sup.9 N/m and less than or equal to 8.0×10.sup.9 N/m.

An actuation system includes a power drive unit that drives a plurality of drive shafts that each has a first end individually connected to the power drive unit. The power drive unit includes a geartrain including a plurality of individual gears that are offset relative to each other along the gearbox, and a motor-driven rotation of one of the plurality of individual gears drives rotation of the other individual gears, and each of the plurality of individual gears rotates to drive rotation of a respective one of the plurality of drive shafts. A plurality of torque brakes is mounted to the gearbox, the torque brakes being mechanically coupled to respective individual gears and drive shafts. When the torque being passed through is above a predetermined threshold value, a locking of one of the torque brakes stops rotation of all gears simultaneously to maintain positional symmetry in the actuation system.

A geared motor, e.g., a gear unit or a bevel gear unit, which is able to be driven by an electric motor, includes a housing part, which is produced by a die casting method, during or after which sliders are moved, in particular pulled out, in respective drawing directions for the demolding, and an input shaft. The housing part includes a channel, demolded in a first drawing direction, in particular, using a first slider, the channel being adapted to extend through the wall of the housing and ending in the interior space region of the gear unit. The drawing direction has a non-vanishing angle in relation to the axis of rotation of the input shaft, its angle in particular amounting to between 5° and 45°, e.g., between 5° and 20°.

A geared motor, e.g., a gear unit or a bevel gear unit, which is able to be driven by an electric motor, includes a housing part, which is produced by a die casting method, during or after which sliders are moved, in particular pulled out, in respective drawing directions for the demolding, and an input shaft. The housing part includes a channel, demolded in a first drawing direction, in particular, using a first slider, the channel being adapted to extend through the wall of the housing and ending in the interior space region of the gear unit. The drawing direction has a non-vanishing angle in relation to the axis of rotation of the input shaft, its angle in particular amounting to between 5° and 45°, e.g., between 5° and 20°.

A combined cycle power generation system for an aircraft includes fuel cell and supercritical CO.sub.2 cycles. The fuel cell cycle includes a compressor and turbine disposed on a first shaft, a fuel cell in fluid communication with the compressor and a fuel source, and a combustor in fluid communication with the fuel cell and the turbine. The combustor is configured to combust partially spent fuel from the fuel cell and produce combustion exhaust gas for delivery to the turbine. The supercritical CO.sub.2 cycle includes a compressor and turbine disposed on a second shaft, a supercritical CO.sub.2 fluid circuit in thermal communication with the combustor and configured to deliver CO.sub.2 to the turbine and compressor, and a heat exchanger in thermal communication with the supercritical CO.sub.2 fluid circuit and a source of cooling fluid. A mechanical linkage is configured to transfer power from the second shaft to the first shaft.

A window covering includes a housing, a covering material, a spindle, and a driving device. The spindle and the driving device are provided at the housing. The driving device includes a motor having a shaft, and an epicyclic gearing decelerating device having an input end and an output end connected to the shaft and the spindle, respectively. Whereby, the spindle can drive the covering material to expand or to collapse. The epicyclic gearing decelerating device includes a ring portion and at least a planet gear assembly which is coupled between the input end and the output end. The planet gear assembly includes a plurality of planet gears having a Shore A durometer hardness of 45-90, which is rotatable along the fixedly provided ring portion. While being driven to move, a lower end of the covering material moves at a speed higher than 65 mm per second.

The disclosure provides rotary machines that include, in one embodiment, a shaft defining a central axis A, the shaft having a first end and a second end. The shaft can have a first gearbox disposed thereon defining one or more cavities therein. At least one contour is slidably received into an arcuate cavity in an exterior surface of the gearbox. The contour has a convex outer surface that cooperates with an inwardly facing curved surface of a housing to form a working volume. A gearbox mechanism consisting of gears, crankshafts, bearings and connecting rod creates an oscillatory motion 2 times per revolution such that the contour can navigate about the arcuate cavity without contacting the cavity at a high rate of rotating speed. Thus, said working volume can expand and compresses twice per rotatable shaft revolution.