An engine includes a housing defining an annular bore and a piston assembly disposed within the annular bore. The engine includes at least one valve configured to oscillate between a first position within the annular bore to allow the piston assembly to travel from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position to define a combustion chamber relative to the piston assembly at the second location. The engine includes an exhaust gas port disposed in fluid communication with the combustion chamber and a fuel distribution assembly configured to mix fuel from a fuel source and air from an air source into a fuel and air mixture at a location external to the combustion chamber and to deliver the fuel and air mixture to the combustion chamber.

An engine includes a housing defining an annular bore and a piston assembly disposed within the annular bore. The engine includes at least one valve configured to oscillate between a first position within the annular bore to allow the piston assembly to travel from a first location proximate to the at least one valve to a second location distal to the at least one valve and a second position to define a combustion chamber relative to the piston assembly at the second location. The engine includes an exhaust gas port disposed in fluid communication with the combustion chamber and a fuel distribution assembly configured to mix fuel from a fuel source and air from an air source into a fuel and air mixture at a location external to the combustion chamber and to deliver the fuel and air mixture to the combustion chamber.

A toroidal combustion engine is provided. The toroidal combustion engine includes a first and a second toroidal cylinder which share a single common intersection to define a combustion chamber. The first toroidal cylinder carries a first piston set, while the second toroidal cylinder carries a second piston set. The first and second piston sets are each rotatable about circular paths which are disposed in planes that are perpendicular to one another.

A toroidal combustion engine is provided. The toroidal combustion engine includes a first and a second toroidal cylinder which share a single common intersection to define a combustion chamber. The first toroidal cylinder carries a first piston set, while the second toroidal cylinder carries a second piston set. The first and second piston sets are each rotatable about circular paths which are disposed in planes that are perpendicular to one another.

A transmission assembly for a rotary piston and cylinder device, comprising a rotor including a piston, a stator, a shutter including a slot to receive the piston, and a first gear and a gear sub-assembly, the first gear connectable to a rotatably mounted shutter of the device, and the first gear extending from a side of the shutter, and the first gear connected to the gear sub-assembly which converts rotation to an axis of rotation different to that of the shutter.

A transmission assembly for a rotary piston and cylinder device, comprising a rotor including a piston, a stator, a shutter including a slot to receive the piston, and a first gear and a gear sub-assembly, the first gear connectable to a rotatably mounted shutter of the device, and the first gear extending from a side of the shutter, and the first gear connected to the gear sub-assembly which converts rotation to an axis of rotation different to that of the shutter.

A rotary piston and cylinder device (1) comprising a rotor (2), a stator and a shutter disc (3), the rotor comprising a piston (5) which extends from the rotor into the cylinder space, the rotor and the stator together defining the cylinder space, the shutter disc passing through the cylinder space and forming a partition therein, and the disc comprising a slot (3a) which allows passage of the piston therethrough, and a surface of the rotor and a surface of the stator opposing each other forming a close-running surface pair, and at least one of the surfaces comprising an abradable coating (10) which is provided with a plurality of recess formations, and the recess formations are discontinuous from each other.

A rotary piston and cylinder device having a rotor, a stator and a shutter disc, the rotor including a piston which extends from the rotor into the cylinder space, the rotor and the stator together defining the cylinder space, the shutter disc passing through the cylinder space and forming a partition, and the disc having a slot which allows passage of the piston, the shutter disc having a circumferential surface that forms a seal with the rotor, the circumferential surface defining at least one close running line with the rotor, and the at least one close-running line offset from a rotor plane which lies on a radius of the rotor and which includes the axis of rotation of the rotor.

A rotary piston and cylinder device comprising a rotor (2), comprising a rotor surface (2a), a stator (4), a rotatable shutter (3), a piston (5) which extends from the rotor surface, the rotor surface and the stator together defining an annular chamber, and the piston arranged to rotate, through the annular chamber, and the rotor surface being orientated at an incline to a plane (P-P) substantially perpendicular to the axis of rotation (A-A) of the rotor and the rotor surface faces generally away from, or outwardly of, the axis of rotation of the rotor.

A rotary piston and cylinder device comprising a rotor (2), comprising a rotor surface (2a), a stator (4), a rotatable shutter (3), a piston (5) which extends from the rotor surface, the rotor surface and the stator together defining an annular chamber, and the piston arranged to rotate, through the annular chamber, and the rotor surface being orientated at an incline to a plane (P-P) substantially perpendicular to the axis of rotation (A-A) of the rotor and the rotor surface faces generally away from, or outwardly of, the axis of rotation of the rotor.