One embodiment may include a rotary engine, whose cylinder is in doughnut-shape. A cross-section of the cylinder is circular. The engine includes a pair of rotation disks, a power disk and passive disk. A power-output shaft is coaxial with an axis of the cylinder. A power piston and passive piston rotate around an axis of the power-output shaft. A space between the power piston in front and the passive piston at the back is a working chamber. When combustion and expansion take place in the working chamber, the power piston will be pushed forward continuously by the expanding gases, and output power via the power-output shaft. The passive piston relies on a driving system to drive it moving forward. Volume of the working chamber varies within one revolution of rotation. Larger volume of the working chamber causes combustion and expansion. Smaller volume of the working chamber causes compression and emission.

The present disclosure relates to a rotary engine which includes a cylinder having a gas inlet and a gas outlet, two rotors which are mounted inside the cylinder and can rotate freely, pistons fixed on the rotors, an ignition device provided on an inner wall of the cylinder and a planetary conical gear differential located outside the cylinder. The planetary conical gear differential includes a first sun gear and a second sun gear. The first rotor and the second rotor are superposed concentrically, the first rotor is connected to the first sun gear through a spindle, and the first rotor and the second rotor are connected to the planetary conical gear differential on a same side of the planetary conical gear differential. The cylinder is a circular ring body. The pistons are in circular motion along with the rotors. A differential rotary engine capable of rotating normally is provided.

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.

A multiple vane kinetic system produces variation in an enclosed volume between pairs of radial vane sets independent of each other and coaxial with a central axis within a annular casing that encapsulates the vane sets. The system operates in a sequence where the vane sets function as rotating links of the mechanism for a particular period, which is preceded and succeeded by another period where either vane sets successively alternate between being a fixed link and a rotating link of the mechanism and during the former period the volumes between vanes remain constant as long as the vane sets have equal angular velocities, otherwise varies at rates proportional to differing angular velocities. The two time periods are controlled by timing devices actuating vane sets to be coupled and decoupled with a power shaft and the variation in length of two time periods makes roto-dynamic variable displacement machine.

A multiple vane kinetic system produces variation in an enclosed volume between pairs of radial vane sets independent of each other and coaxial with a central axis within a annular casing that encapsulates the vane sets. The system operates in a sequence where the vane sets function as rotating links of the mechanism for a particular period, which is preceded and succeeded by another period where either vane sets successively alternate between being a fixed link and a rotating link of the mechanism and during the former period the volumes between vanes remain constant as long as the vane sets have equal angular velocities, otherwise varies at rates proportional to differing angular velocities. The two time periods are controlled by timing devices actuating vane sets to be coupled and decoupled with a power shaft and the variation in length of two time periods makes roto-dynamic variable displacement machine.

Rotary internal combustion engine includes a body made of four parts, each of which is an L-shaped fragment, and, when connected, forming two mutually perpendicular ring-shaped walls in plan view with ribs on the outer surface and an annular groove inside, which form two passages, each of which contain a torus-shaped rotor, which can move along the groove. Each torus-shaped rotor has longitudinal notches located outside or inside the rotor forming cavities between the rotor and groove surface, connected to chambers located outside the walls. The intake and exhaust windows are made in the walls communicating with the cavities between the rotor and groove surface. The rotors are interconnected by the kinematic chain of rotation synchronization made of successively engaged gears, one of which is engaged with one torus-shaped rotor, and the last of the gears is engaged with the output shaft, rigidly connected with another torus-shaped rotor.

The present invention relates to a drive unit (1), usable, in particular, for the construction of heat engines designed to use thermodynamic cycles of the Rankine, Rankine-Hirn, Brayton and Stirling type, comprising a casing (2) delimiting therein an annular chamber (12), two triads of pistons (7a-7b-7c; 9a-9b-9c) rotatably housed in the casing of the annular cylinder (or toroidal cylinder), a three-shaft movement system (18) configured to transmit motion from and/or to the two triads of pistons; wherein said system comprises a primary shaft (17), a first secondary shaft (19) and a second secondary shaft (20), and each secondary shaft is connected to a respective triad of pistons (7a-7b-7c; 9a-9b-9c); the rotation of the primary shaft having a constant angular velocity determines a periodic cyclic variation in the angular velocity of rotation of the two secondary shafts. The invention further relates to a heat engine (29), comprising the aforesaid drive unit (1), configured so as to carry out a Rankine or Rankine-Hirn thermodynamic cycle, capable of producing electrical energy and heat usable for any purpose; the same invention further relates to a heat engine (51), comprising the aforesaid drive unit (1), configured so as to carry out a new pulsating heat cycle derived from the Stirling Stirling cycle and capable of producing electrical energy and heat usable for any purpose; the same invention further relates to a pneumatic motor (61) comprising the aforesaid drive unit (1), configured so as to transform the compressed air at high pressure, contained in a tank, into mechanical energy usable for any purpose.

The radial piston rotary device with compact gear drive mechanism includes a base, a casing mounted to the base, and a gearbox coupled to the casing. The casing houses a piston assembly with a pair of first radial pistons and a pair of second radial pistons coaxially mounted to the first radial pistons with each pair rotating at asynchronous, cyclically varying velocities. During a power cycle, a leading pair of radial pistons powers the associated gear assembly, and the gear assembly drives a flywheel assembly. A drive shaft axially extends from the flywheel assembly outside the gearbox to be selectively coupled to a driven component. The flywheel drives the pair of lagging radial pistons. During operation, each pair of radial pistons rotate at cyclically varying angular velocities out of phase with each other, yet produce a uniform output to the drive shaft.

The radial piston rotary device with compact gear drive mechanism includes a base, a casing mounted to the base, and a gearbox coupled to the casing. The casing houses a piston assembly with a pair of first radial pistons and a pair of second radial pistons coaxially mounted to the first radial pistons with each pair rotating at asynchronous, cyclically varying velocities. During a power cycle, a leading pair of radial pistons powers the associated gear assembly, and the gear assembly drives a flywheel assembly. A drive shaft axially extends from the flywheel assembly outside the gearbox to be selectively coupled to a driven component. The flywheel drives the pair of lagging radial pistons. During operation, each pair of radial pistons rotate at cyclically varying angular velocities out of phase with each other, yet produce a uniform output to the drive shaft.