An opposed, free-piston engine includes a pair of adjacent cylinders, each extending from a first cylinder end to a second cylinder end along an elongate axis and having a first cylinder housing a first pair of opposed, free pistons including a first piston housed towards the first cylinder end and a second piston housed towards the second cylinder end; a second cylinder housing a second pair of opposed, free pistons having a third piston and a fourth piston; and a pair of link rods including a first link rod and a second link rod. The first link rod has a first link rod end and a second link rod end, the second link rod having a third link rod end and a fourth link rod end.

In an opposed-piston engine, a piston has a top land. The piston top land has a non-cylindrical shape which affords more clearance with a piston bore to thrust and anti-thrust sides than to front-facing and rear facing sides.

An electric device has a driveshaft with at least one stator cylinder positioned between opposing, curvilinear shaped cams mounted on the driveshaft, where the center axis of the stator cylinder is parallel with but spaced apart from the driveshaft axis. A magnet assembly is disposed in each end of the stator cylinder, with one magnet assembly engaging one cam and the other magnet assembly engaging the other cam. Each magnet assembly includes a cam follower that can move along a curvilinear shaped cam. A magnet slide arm attached to the cam reciprocates magnets carried on the magnet slide arm through electromagnetic windings disposed around the stator cylinder. An electrical input delivered to the windings can reciprocate the arm, driving the cams to rotate the driveshaft. Alternatively, rotation of the driveshaft can be used to reciprocate the arm to induce electric current in the windings.

Improvements to an engine comprise an air compressor cylinder with a piston, a combustion chamber cylinder with a piston. An engine has added an expansion chamber cylinder with a piston. Pistons each have a connecting rod and connecting rod head and associated parts adapted for reciprocating motion via combustion products, and a transmission associated with the engine. Improvements are to the piston seals, ignition assembly, valve shape and stem/rocker, valve operating mechanism, construction of head, heat management/heat shield, connecting rod/piston rotator, engine balancing, fuel pump placement, and a machining process.

An internal combustion-type engine or powertrain that is capable of burning wet-alcohol fuel mixture and including a piston reciprocating within a cylinder attached to a cylinder head and connecting to a crank shaft via a connecting rod. An intake cam and valve is mounted within an intake port formed in the cylinder head and an exhaust cam and valve is mounted within an exhaust port also formed in the cylinder head. A pressurized fuel source is introduced into the cylinder by a fuel injector and the percentage of water in the alcohol/water mix operates to prolong the cylinder pressure in order to increase a mean effective pressure (IMEP), leading to a higher torque (improved Brake Mean Effective Pressure—BMEP) of the engine via a longer pressure pulse attained during the period of preferred mechanical advantage of the crank-arm of the engine.

An internal combustion-type engine or powertrain that is capable of burning wet-alcohol fuel mixture and including a piston reciprocating within a cylinder attached to a cylinder head and connecting to a crank shaft via a connecting rod. An intake cam and valve is mounted within an intake port formed in the cylinder head and an exhaust cam and valve is mounted within an exhaust port also formed in the cylinder head. A pressurized fuel source is introduced into the cylinder by a fuel injector and the percentage of water in the alcohol/water mix operates to prolong the cylinder pressure in order to increase a mean effective pressure (IMEP), leading to a higher torque (improved Brake Mean Effective Pressure—BMEP) of the engine via a longer pressure pulse attained during the period of preferred mechanical advantage of the crank-arm of the engine.

A hybrid drive system has two sources of driving power: a non-combustion drive system to provide mechanical torque and rotation to a driveshaft, and an opposed-piston, internal combustion engine configured to provide energy for the non-combustion drive system.

A hybrid drive system has two sources of driving power: a non-combustion drive system to provide mechanical torque and rotation to a driveshaft, and an opposed-piston, internal combustion engine configured to provide energy for the non-combustion drive system.

An internal combustion engine system includes a reciprocating compressor for pressurizing a fluid medium and having a compressor cylinder for accommodating a compressor piston. The compressor cylinder has a main cylinder volume and a secondary adjustable volume in fluid communication with the main cylinder volume so as to provide a variable geometrical compression ratio.

Compact and quiet opposed piston engines (OPEs) are provided. Though compact and quiet, the OPEs provide substantial mechanical shaft power that is required for a range of applications. The inventive OPEs may have a plurality of size displacements.