A new engine which incorporates the advantages found in a two-stroke with the advantages found in a four-stroke engine combined.

An internal combustion 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 piston may be configured to move in the cylinder in a first stroke from one end to another. The first stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion. The non-expansion stroke portion may include a scavenging phase. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.

An internal combustion 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 piston may be configured to move in the cylinder in a work stroke from one end to another. The work stroke may include an expansion stroke portion, a momentum stroke portion, and a compression stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and a location outside the cylinder.

Various embodiments are described herein for methods and devices that relate to a drive mechanism, and a power mechanism that can be used 5 individually or together in an engine to obtain increased efficiency are provided according to the teachings herein. The embodiments described herein generally employ at least one of drive mechanisms that provide for non-sinusoidal motion and embedded piston arrangements.

Various embodiments are described herein for methods and devices that relate to a drive mechanism, and a power mechanism that can be used 5 individually or together in an engine to obtain increased efficiency are provided according to the teachings herein. The embodiments described herein generally employ at least one of drive mechanisms that provide for non-sinusoidal motion and embedded piston arrangements.

An internal combustion 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 piston may be configured to move in the cylinder in a first stroke from one end to another. The first stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion. The non-expansion stroke portion may include a scavenging phase. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.

A high efficiency positive Displacement Heat Machines, for applications such as engines with external heating, Internal Combustion Engines with reduced dirty emissions, heat pumps for ecology clear coolers or heaters, working with air from any source of mechanical energy, thermal processes with approximately constant pressure using an external High and Low Pressure Chambers (HPC and LPC that may be the Atmosphere) that are connecting to a Working Chamber (WC) correspondingly at the end of compression and expansion stages. The disclosed engines and heat pumps operate with displacing at least a part of the WF between said WC and HPC, without changing volume of the WC; with Pulse Pause Modulation of crankshaft speed; with remote expander for engine or compressor for heat pump. The expander or compressor are arranged without transferring mechanical work from another parts of the heat machine. The expander is used as power output from the engine, and the compressor is used as power input to the heat pump.

A high efficiency positive Displacement Heat Machines, for applications such as engines with external heating, Internal Combustion Engines with reduced dirty emissions, heat pumps for ecology clear coolers or heaters, working with air from any source of mechanical energy, thermal processes with approximately constant pressure using an external High and Low Pressure Chambers (HPC and LPC that may be the Atmosphere) that are connecting to a Working Chamber (WC) correspondingly at the end of compression and expansion stages. The disclosed engines and heat pumps operate with displacing at least a part of the WF between said WC and HPC, without changing volume of the WC; with Pulse Pause Modulation of crankshaft speed; with remote expander for engine or compressor for heat pump. The expander or compressor are arranged without transferring mechanical work from another parts of the heat machine. The expander is used as power output from the engine, and the compressor is used as power input to the heat pump.

An internal combustion 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 piston may be configured to move in the cylinder in a work stroke from one end to another. The work stroke may include an expansion stroke portion, a momentum stroke portion, and a compression stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and a location outside the cylinder.

An internal combustion 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 piston may be configured to move in the cylinder in a work stroke from one end to another. The work stroke may include an expansion stroke portion and a non-expansion stroke portion. The non-expansion stroke portion may include a momentum stroke portion, and a compression stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. Passageways in the piston rod portions may be configured to communicate gases between a combustion chamber and other locations.