Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a driver section may be provided in a free-piston combustion engine for storing energy during an expansion stroke. The driver section may be configured to store sufficient energy to perform the subsequent stroke. In some embodiments, the driver section may be configured to store sufficient energy so as to enable the engine to operate continuously across engine cycles without electrical energy input. A linear electromagnetic machine may be provided in a free-piston combustion engine for converting the kinetic energy of a piston assembly into electrical energy.

Linear generators with a piston having a valve are described herein. The linear generator includes a combustion module and at least one linear motor. The linear motor includes at least one piston having: a piston head with an opening therein; a piston skirt opposed to the piston head; a piston side wall extending between the piston head and the piston skirt, the piston side wall having at least one port therein. The piston also includes a valve mechanism movable relative to each of the piston head, the piston seat and the piston side wall. The valve mechanism includes a valve stem extending through the piston skirt and the interior piston volume into a mover shaft of the motor, and a valve head coupled to the valve stem and configured to cover the opening of the piston head.

A vehicle may include an electromechanical energy recovery system and be configured to perform a method for its operation.

Various embodiments of the present invention are directed toward a linear combustion engine, comprising: a cylinder having a cylinder wall and a pair of ends, the cylinder including a combustion section disposed in a center portion of the cylinder; a pair of opposed piston assemblies adapted to move linearly within the cylinder, each piston assembly disposed on one side of the combustion section opposite the other piston assembly, each piston assembly including a spring rod and a piston comprising a solid front section adjacent the combustion section and a gas section; and a pair of linear electromagnetic machines adapted to directly convert kinetic energy of the piston assembly into electrical energy, and adapted to directly convert electrical energy into kinetic energy of the piston assembly for providing compression work during the compression stroke.

Linear generators with a piston having a valve are described herein. The linear generator includes a combustion module and at least one linear motor. The linear motor includes at least one piston having: a piston head with an opening therein; a piston skirt opposed to the piston head; a piston side wall extending between the piston head and the piston skirt, the piston side wall having at least one port therein. The piston also includes a valve mechanism movable relative to each of the piston head, the piston seat and the piston side wall. The valve mechanism includes a valve stem extending through the piston skirt and the interior piston volume into a mover shaft of the motor, and a valve head coupled to the valve stem and configured to cover the opening of the piston head.

Various embodiments of the present invention are directed toward a linear combustion engine, comprising: a cylinder having a cylinder wall and a pair of ends, the cylinder including a combustion section disposed in a center portion of the cylinder; a pair of opposed piston assemblies adapted to move linearly within the cylinder, each piston assembly disposed on one side of the combustion section opposite the other piston assembly, each piston assembly including a spring rod and a piston comprising a solid front section adjacent the combustion section and a gas section; and a pair of linear electromagnetic machines adapted to directly convert kinetic energy of the piston assembly into electrical energy, and adapted to directly convert electrical energy into kinetic energy of the piston assembly for providing compression work during the compression stroke.

A linear electro-mechanical system comprising: a stator including at least first and second stator electronic circuits or groups of circuits; a free piston mover movable in a reciprocating motion relative to the stator, the free piston including: a piston surface; a translator configured so that an electromagnetic force may be applied on the free piston mover by one or more of the stator electronic circuits or groups of circuits; and one or more translator electronic circuits, the system further comprising a switching device for each of the first and second stator electronic circuits or groups of circuits such that the current in each of the first and second stator electronic circuits or groups of circuits is independently controllable, and wherein at least one of the translator electronic circuits is configured to receive power from at least one of the independently controlled stator electronic circuits or groups of circuits during at least part of the stroke of the free piston mover.

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.

A linear piston engine includes a housing having a combustion chamber located between opposing first and second piston chambers. A first piston assembly is located within the first piston chamber, and a second piston assembly is located within the second piston chamber. Each piston assembly includes a piston for reciprocating within the piston chamber. The piston is located adjacent to the combustion chamber. Each piston assembly also includes a crankshaft coupled to the piston for guiding the piston through a power stroke and a return stroke, and a linear output member coupled to the piston for providing a linear output motion based on reciprocating motion of the piston.

Various embodiments of the present disclosure are directed towards free-piston combustion engines. As described herein, a driver section may be provided in a free-piston combustion engine for storing energy during an expansion stroke. The driver section may be configured to store sufficient energy to perform the subsequent stroke. In some embodiments, the driver section may be configured to store sufficient energy so as to enable the engine to operate continuously across engine cycles without electrical energy input. A linear electromagnetic machine may be provided in a free-piston combustion engine for converting the kinetic energy of a piston assembly into electrical energy.