A drive system includes a first gear set and a second gear set, each including a sun gear, a ring gear, a plurality of planetary gears coupling the sun gear to the ring gear, and a carrier rotationally supporting the plurality of planetary gears, a first electrical machine coupled to the sun gear of the first gear set, a second electrical machine coupled to the sun gear of the second gear set, a connecting shaft coupled to the ring gear of the first gear set, a driveshaft that transports power from the electrical machines to a tractive element, a first clutch selectively rotationally coupling the first carrier and the second carrier to the driveshaft, and at least one of a second clutch selectively rotationally coupling the second electrical machine to the connecting shaft and a third clutch selectively rotationally coupling the second gear set to the driveshaft.

A power transmission system is disclosed for infinitely variable speed capability. The power transmission system includes a pair of power units, each configured to deliver a rotational torque to drive an output element. A transmission arrangement receives the rotational torques from the power units and delivers a resulting torque to the output element. The transmission arrangement includes a gear set coupling the one power unit to the output element to deliver torque through a mechanical meshing engagement that is continuously effected between the first power unit and the output element.

Components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT) having a variator provided with a plurality of tilting, traction planets and traction rings are described. In one embodiment, a variator is coupled to a rangebox to provide multiple operating modes. In another embodiment, a hydraulic system is configured to control the transmission ratio of the variator and the rangebox. Shift-cam-and-sun subassemblies can be used to facilitate shifting of the transmission ratio of a CVT. A transmission housing and bell housing can be adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Related devices include, for example, a pivot arm, a control feedback mechanism, axial force generation and management mechanisms, a control valve integral with an input shaft, a pivot pin hub, and a rotatable carrier configured to support planet-pivot arm assemblies.

An infinitely variable transmission capable of shifting from infinity to zero speed ratios in forward and reverse is provided. The transmission offers reciprocal blocking and supports high torque and power, while requiring a fixed number of planetary gears and a hydraulic flow control, without brakes and/or clutch by varying the angular displacement or rotational movement separating the contained vectors (speed and torque) to exploit, in a reciprocal manner, the working flow by maintaining the full potential of the movement force source without a continuity flow break-up.

A mechanical-double ring-hydraulic composite transmission mechanism includes an input member, a convergence mechanism, a hydraulic transmission mechanism, a double ring mechanism, an output member, a clutch assembly, and a brake assembly. The clutch assembly connects a left planetary gear train to a right planetary gear train. The clutch assembly connects the input member to the hydraulic transmission mechanism, the double ring mechanism, the left planetary gear train, and the right planetary gear train. The clutch assembly connects the hydraulic transmission mechanism to the right planetary gear train. The clutch assembly connects the double ring mechanism to the left planetary gear train. The clutch assembly connects the left planetary gear train and the right planetary gear train to the output member. A continuous transmission ratio between the input member and the output member is provided by adjusting a displacement ratio of the hydraulic transmission mechanism.

Methods and systems for a hydromechanical transmission are provided herein. In one example, the transmission system includes a hydraulic pump and a hydraulic motor rotationally coupled in parallel with a first planetary gear set and a second planetary gear set. In the system, sun gears of the planetary gear sets are rotationally coupled to the hydraulic motor, a carrier of the first planetary gear set is rotationally coupled to a first clutch and a second clutch, and a ring gear of the second planetary gear set is rotationally coupled to a third clutch.

A drivetrain for connection between the output of a prime mover and a load is described herein. The drivetrain comprising a CVT including an input connected to the output of the prime mover and an output; a forward-reverse clutch assembly including first and second inputs and an output connectable to the load; the first input of the forward-reverse clutch assembly being connected to the output of the CVT through a CVT clutch. The drivetrain also includes an IVT gear assembly having a first input connected to the output of the prime mover, a second input connected to the output of the CVT and an output connected to the second input of the forward reverse clutch assembly through an IVT clutch; and an idler gear assembly interconnecting the first and second inputs of the forward-reverse clutch assembly.

A gas turbine engine comprising a compressor, a compressor case surrounding the compressor and a compressor tip injector system is disclosed. The compressor tip injector system comprises a cabin blower system comprising a cabin blower compressor arranged in use to compress air used in a cabin of an aircraft and by the compressor tip injector system. The compressor case comprises one or more injectors of the compressor tip injector system through which in use air from the cabin blower compressor is injected towards blade tip ends of blades of the compressor as they rotate.

In a power transmission device in which a first power transmission path is formed by engagement of a first clutch and a dog clutch and a second power transmission path is formed by engagement of a second clutch, the first clutch is released from a state where the first clutch and the dog clutch are engaged, and when a front-rear rotation speed difference of the dog clutch becomes equal to or greater than a predetermined value after the start of a clutch-to-clutch gear shift for engaging the second clutch, complete release control for releasing the first clutch to lower the torque capacity of the first clutch is performed.

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for infinitely variable transmissions (IVT) having a variator provided with a plurality of tilting spherical planets. In one embodiment, a variator is provided with multiple planet arrays. In another embodiment, a hydraulic system is configured to control the transmission ratio of the IVT. Various inventive idler assemblies and planet-pivot arm assemblies can be used to facilitate adjusting the transmission speed ratio of an IVT. Embodiments of a transmission housing and bell housing are adapted to house components of an IVT and, in some embodiments, to cooperate with other components of the IVT to support operation and/or functionality of the IVT. Various related devices include embodiments of, for example, a control feedback mechanism, axial force generation and management mechanisms, a control valve integral with an input shaft, and a rotatable carrier configured to support planet-pivot arm assemblies.