A rotor assembly for a rotary internal combustion engine is provided. The rotor assembly includes a rotor having a radial groove defined radially in a peripheral surface of the rotor. The groove has a depth and an intermediate shoulder at an intermediate depth. The groove has a first width therealong that is narrower than an intermediate width at the shoulder. An apex seal is received in the groove and protrudes from the peripheral face of the rotor. The apex seal is configured to move radially between a first position and a second position outward of the first position. A biasing member biases the apex seal toward the second position. A platform is disposed in the groove between the apex seal and the biasing member and has a width greater than the first width.

A rotor assembly for a rotary internal combustion engine is provided. The rotor assembly includes a rotor having a radial groove defined radially in a peripheral surface of the rotor. The groove has a depth and an intermediate shoulder at an intermediate depth. The groove has a first width therealong that is narrower than an intermediate width at the shoulder. An apex seal is received in the groove and protrudes from the peripheral face of the rotor. The apex seal is configured to move radially between a first position and a second position outward of the first position. A biasing member biases the apex seal toward the second position. A platform is disposed in the groove between the apex seal and the biasing member and has a width greater than the first width.

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.

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.

The engine comprises an outer shell in the shape of a fixed ring with two lids, an internal rotor with an inlaid central shaft and bearings. On the inner surface of the shell, inlet, compression, explosion and escape chambers are positioned. The internal rotor is endowed with drive axle having a cylindrical body endowed with radial slots which house at least one vane pressed radially against a shell by spring. The outer shell of the Otto engine has a carburetor and a feed duct of the air-fuel mixture. At the start of the explosion chamber the spark plug is positioned. At the end of the explosion chamber an escape chamber with an escape duct is positioned. The outer shell of the Diesel engine has a butterfly valve and an air feed duct. At the start of the explosion chamber a fuel injection spout is positioned, and at the end of the explosion chamber an escape chamber with an escape duct is positioned.

A rotary engine having an outer body having an internal cavity with a peripheral wall having an insert opening defined therethrough in communication with the internal cavity, and a plurality of coolant passages defined through the peripheral wall in proximity of the insert opening, a rotor body rotatable within the internal cavity, and an insert removably received in the insert opening of the peripheral wall, the insert having a subchamber defined therein communicating with the internal cavity, with a minimum width of the insert opening being at least 0.75 inches. An outer body for a rotary engine and a method of inspecting in an internal cavity in an outer body of a rotary engine are also discussed; also, a rotary engine including a fuel injector having a tip received in the injector hole of the peripheral wall without protruding in the insert opening.

A rotary engine includes an insert having a pilot subchamber defined therein and communicating with the internal cavity of the engine. A pilot fuel injector has a tip in communication with the pilot subchamber. An ignition element extends into an element cavity defined through the insert adjacent the pilot subchamber. The element cavity is in communication with the pilot subchamber through a communication opening defined in the insert between the element cavity and the pilot subchamber. The communication opening is smaller than a portion of the ignition element adjacent the communication opening such as to prevent the portion of the ignition element from completely passing through the communication opening upon breaking off of the portion of the ignition element from a remainder of the ignition element. An outer body for a rotary engine and a method of combusting fuel in a rotary engine are also provided.

A rotary internal combustion motor has a stator that houses a compartment defined by two opposite planar surfaces and by an annular surface with elliptical profile, inside which a rotor rotates, which includes a cylindrical drum surrounded by an annular chamber, which is divided into multiple portions by a regularly spaced set of radial blades that are slidingly housed in the cylindrical drum. The motor also has at least one pair of inlet openings, at least one pair of outlet openings, at least one pair of injectors, at least one pair of spark plugs, and at least one pair of pre-heating spark plugs.

A dual-cycle heat engine employing a first cycling working fluid and a second cycling working fluid whose cycles overlap when fused into a combined working stream so as to preserve compression heat generated during compression of the first working fluid thereby yielding enhanced work extraction when complying with additional thermodynamic requirements.

A rotary internal combustion engine with a housing having a fluid passage defined therethrough opening into a portion of its inner surface engaging each peripheral or apex seal of the rotor. An injector has an inlet for fluid communication with a pressurized lubricant source and a selectively openable and closable outlet in fluid communication with the fluid passage for delivering the pressurized lubricant to each seal through the fluid passage. A housing for a Wankel engine and a method of lubricating peripheral seals of a rotor in an internal combustion engine are also discussed.