Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

A linear reciprocating engine may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The engine may further include a first piston rod portion extending from a first face of the double-faced piston through the first combustion chamber, and a second piston rod portion extending from a second face of the piston through the second combustion chamber. Passageways in the piston rod portions may be configured to communicate gases between the combustion chamber and a location outside the cylinder and configured to prevent gases from being exchanged between the cylinder and a location outside the cylinder via a path that crosses both face of the piston.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

An internal combustion engine comprises an engine block defining a cylinder having a longitudinal axis A. A piston is arranged slidably within the cylinder and an impeller is arranged at one end of the cylinder. The impeller is rotatably mounted on a shaft, which extends out of the cylinder and which is driven in rotation by rotation of the impeller. The engine further comprises an anti-rotation formation to prevent the piston rotating about a longitudinal axis of the cylinder and a swirl-inducing vane arranged on the face of the piston which faces the end of the cylinder at which the impeller is arranged. Combustion gas generated by combustion of a fuel in the cylinder between the piston and the impeller is caused to swirl by reaction with the swirl-inducing vane and the swirling combustion gases, in turn, cause the impeller to rotate.

A parallel motion heat energy power machine and a working method thereof, includes a heat collector, an insulating pipe, a gasification reactor, an atomizer, a cylinder, a piston, a piston ring, an automatic exhaust valve, a cooler, a liquid storage tank, a pressure pump, a push-pull rod, an insulating layer, and a housing. The two cylinders are oppositely arranged on the housing in parallel. The piston is arranged inside the cylinder. The piston is provided with the piston ring. The pistons are arranged on both ends of the push-pull rod. The heat collector is connected to the gasification reactor through the insulating pipe. The atomizer is arranged on the air inlet end of the gasification reactor. The parallel motion heat energy power machine and working method thereof has a high heat-energy conversion efficiency. It is energy-saving, environmentally friendly, and less noisy.

An engine may include a cylinder having a first combustion chamber at one end thereof and a second combustion chamber at an opposing end thereof, first and second cylinder heads at an end of the first combustion chamber and the second combustion chamber, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in a first stroke from the first end to the second end of the cylinder. The piston and the cylinder may be configured such that the first stroke includes an expansion stroke portion during which chemical energy from combustion in the first combustion chamber is converted into mechanical power of the piston, and a momentum stroke portion during which the piston continues to move to the second end of the cylinder and gases are exchanged between the first combustion chamber and a location outside the cylinder.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a method and system are provided for displacing a free-piston assembly to achieve a desired engine performance by repeatedly determining position-force trajectories over the course of a propagation path and effecting the displacement of the free-piston assembly based, at least in part, on the position-force trajectory. In a dual-piston assembly free-piston engine, synchronization of the two piston assemblies is provided.

An air motor (10) that has opposing chambers (16, 17) to which compressed air is alternatively delivered to drive the motor (10). The motor (10) has a primary valve (52) that governs deli very of the compressed air to the chambers (16, 17) so at least part of the compressed air is transferred to the other chamber to aid in driving the pistons (18).