A method of operating an internal combustion engine having pilot subchambers communicating with main combustion chambers, the internal combustion engine configured in use to deliver a main fuel injection of a maximum quantity of fuel to the main combustion chambers when the internal combustion engine is operated at maximum load. The method includes delivering a pilot fuel injection of at most 10% of the maximum quantity to the pilot subchambers, igniting the pilot fuel injection within the pilot subchambers, directing the ignited fuel from the pilot subchambers to the main combustion chambers, and delivering a main fuel injection of a main quantity of fuel to at least one of the main combustion chambers receiving the ignited fuel, with the main quantity being at most 10% of the maximum quantity.

A rotary internal combustion engine including a rotor assembly where at least a first and a second of the combustion chambers have unequal theoretical volumetric ratios. Also, a rotary internal combustion engine including first and second rotor assemblies where at least one of the combustion chambers of the first rotor assembly and at least one of the combustion chambers of the second rotor assembly have unequal effective volumetric compression ratios and/or unequal effective volumetric expansion ratios.

An internal combustion rotary engine that produces mechanical torque is provided. The engine includes an annular planar housing, a rotor, and first and second valves. The planar housing has a substantially circular annulus flanked by first and second cavities and an axial shaft disposed between the cavities. The rotor is disposed on the shaft and rotates within the annulus; The first and second valves are disposed within respective the cavities. Each valve has an arc wedge having outer convex surface and an inner concave surface, a shaft hole between and parallel to the surfaces along a rocking axis, and a pivot shaft that passes through the shaft hole to enable the wedge to rock back and forth within the cavity.

An internal combustion rotary engine that produces mechanical torque is provided. The engine includes an annular planar housing, a rotor, and first and second valves. The planar housing has a substantially circular annulus flanked by first and second cavities and an axial shaft disposed between the cavities. The rotor is disposed on the shaft and rotates within the annulus; The first and second valves are disposed within respective the cavities. Each valve has an arc wedge having outer convex surface and an inner concave surface, a shaft hole between and parallel to the surfaces along a rocking axis, and a pivot shaft that passes through the shaft hole to enable the wedge to rock back and forth within the cavity.

A rotary engine comprised of a pair of counterrotating rotors within a non-rotating outer housing. Each of the rotors is coupled to a common power shaft, one directly and the other through a reversing gear arrangement. Both are driven by the hyper-expansion of combustion gases in a repeating combustion cycle. Each has a generally circular, nearly frictionless working surface perpendicular to the power shaft axis. Each rotor surface defines chambers which rotate past each other. Within such chambers, compressed air and fuel are introduced, mixed, ignited, allowed to hyper-expand (and thus cause the rotation) and exhausted. The power shaft may be connected to a conventional clutch, torque converter, gearbox, differential, alternator or a similar system.

The synchronous machine module includes a synchronous machine and a rotational speed controller for controlling a rotational speed of the synchronous machine, which rotational speed controller has a detector for detecting a variable which is formed by the effective power or is dependent thereon. The rotational speed controller is designed to set the rotational speed of the synchronous machine and/or the time profile thereof as a function of the detected variable and/or its time profile. The vehicle drive has such a synchronous machine module and a power generator, which in order to supply the synchronous machine module is connected thereto. The vehicle is, in particular, an aircraft and has such a vehicle drive and/or such a synchronous machine module.

An apparatus including a first piston member rotatable about a first rotational axis and a rotor with a first chamber and pivotable about a second rotational axis. The first piston member extends across the first chamber. The rotor and first piston member are rotatable around the first rotational axis, and the rotor is pivotable about the second rotational axis to permit a relative pivoting motion between the rotor and the first piston member linked to the rotor rotating about the first rotational axis.

A rotational engine system comprises a rotational engine and a propulsion system. The rotational engine includes an outer ring enclosure, an inner ring component, and a drive gear. The inner ring component includes a piston and a drive gear engagement portion. The piston is configured to travel within the outer ring enclosure along a circumference of the outer ring enclosure. The drive gear engagement portion is configured to rotate as the piston travels along the circumference of the circular shape of the outer ring enclosure. The drive gear is coupled to the drive gear engagement portion of the inner ring component such that rotation of the drive gear engagement portion rotationally drives the drive gear. The propulsion system is configured to deliver propulsive energy to propel the piston along the circumference of the outer ring enclosure.

A rotational engine system comprises a rotational engine and a propulsion system. The rotational engine includes an outer ring enclosure, an inner ring component, and a drive gear. The inner ring component includes a piston and a drive gear engagement portion. The piston is configured to travel within the outer ring enclosure along a circumference of the outer ring enclosure. The drive gear engagement portion is configured to rotate as the piston travels along the circumference of the circular shape of the outer ring enclosure. The drive gear is coupled to the drive gear engagement portion of the inner ring component such that rotation of the drive gear engagement portion rotationally drives the drive gear. The propulsion system is configured to deliver propulsive energy to propel the piston along the circumference of the outer ring enclosure.

Pressure changing devices and methods of making and using the same are disclosed. One pressure changing device includes an elliptic cylinder and a piston that has an external surface with a trochoid cross-section. Another pressure changing device includes a piston and a rotating cylinder that has an internal surface with a trochoid cross-section. Another pressure changing device includes two fixed axes, one for rotation of one component and another for orbiting or oscillation of the other component. The devices and methods include stacked pressure changing devices with one or more common shafts. The pressure changing device may be easier and less expensive to manufacture and repair than prior pressure changing devices of the same or similar functionality, and can provide efficient gap sealing in a high-pressure expansion part of a compression or expansion cycle.