A hybrid internal combustion engine (HICE) comprises an engine block defining one or more cylinder bores, a cylinder liner disposed within each of the one or more cylinder bores, and a piston comprising a permanent magnet. Each cylinder liner comprises a non-ferromagnetic material and an induction coil encased within the non-ferromagnetic material. The permanent magnet of each piston can be reciprocated via electrical power received by an appurtenant induction coil or repeatedly transported across the height of the induction coil to generate electrical energy. A hybrid powertrain of a vehicle includes a HICE, an electrical energy storage device, and a power electronics module configured to transfer the generated electrical energy between each of the one or more cylinder liners and the energy storage device. A motor/generator engaged with a wheel can drive the wheel or generate power via braking thereof.

The present invention relates to a free-piston linear apparatus, comprising a piston arranged within a cylinder, said piston being configured for linear displacement within the cylinder; a combustion chamber arranged on one side of said piston and a gas expansion chamber arranged on an opposite side of said piston, wherein said piston is drivable under the action of a fuel medium expanding in the combustion chamber; an exhaust vent arranged to release exhaust gas from the combustion chamber to an exhaust system, wherein said exhaust system comprises a heat exchanger configured to transfer residual heat from said exhaust gas to said gas expansion chamber in order to heat the gas expansion chamber; and wherein said gas expansion chamber comprises at least one gas port for injecting and/or releasing gas into/from the gas expansion chamber.

The present invention refers to a linear electric generator, comprising: at least one intake port; at least one expansion chamber, and at least one expansion piston; at least one central cylinder; at least two reduced cylinders, wherein the diameter of said reduced cylinders is smaller than the diameter of the central cylinder, and wherein each reduced cylinder comprises a partition; at least one electric power-generating set of pistons, wherein each piston of said set of pistons is located inside the central cylinder and is suitable to linearly move inside the inner void of a reduced cylinders through the partitions of the reduced cylinders, and wherein each said piston is connected to an oscillator; at least one fluid chamber suitable to comprise incompressible fluid, wherein said fluid chamber is the void between the edge of the expansion piston closer to the electric power-generating pistons and the electric power-generating pistons themselves; at least two sets of magnets, wherein each set of magnets is attached to an oscillator; at least two end sections that comprise coil windings; and at least one outlet port, suitable to allow the evacuation of fluids from said expansion chamber. The invention also refers to a method for energy transformation.

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.

An integrated linear generator system includes, for example, a generator assembly, a control system, a frame system, an exhaust system, an intake system, a cooling system, a bearing system, one or more auxiliary systems, or a combination thereof. The generator system is configured to generate power, as controlled by the control system. The generator assembly may include an opposed- and free-piston linear generator, configured to operate on a two-stroke cycle. The intake and exhaust systems are configured to provide reactants to and remove products from the generator assembly, respectively. The cooling system is configured to effect heat transfer, material temperature, or both, of components of the integrated linear generator system. The bearing system is configured to constrain the off-axis motion of translators of the generator assembly without applying significant friction forces. The frame system is configured to manage rigidity, flexibility, and alignment of components of the integrated linear generator system.

Various embodiments of the present invention are directed toward a linear generator, comprising: a cylinder having a cylinder wall and a pair of ends, the cylinder including a reaction 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 reaction section opposite the other piston assembly, each piston assembly including a spring rod and a piston comprising a solid front section adjacent the reaction 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.

An internal combustion engine, includes a cylinder; a piston supported in the cylinder for linear displacement, wherein the piston is operatively connected with a crankshaft of the internal combustion engine via a piston rod; a linear motor including a stator and a rotor, wherein the stator has an independently operable stator element assigned to the cylinder and partially surrounding the piston in circumferential direction with respect to a longitudinal center axis of the cylinder, wherein the rotor is assigned to or forms a part of the piston, and wherein the linear motor being operable for exerting on the piston a compensation force directed in radial direction.

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.

A five-spindle engine system having a stable center of gravity that operates without oil lubrication, an opposed-piston four-cylinder, two-stroke combustion engine, a double-acting opposed-piston pressure-gradient drive, a multi-rotor/multi-stator/multi-phase disk generator/disk motor including windings printed on printed circuit boards, and/or a heat pump may be integrated in the system and housed in a common sealed housing.

A free piston apparatus includes a piston receptacle in which a piston device having a piston is reciprocable along an axis. The piston receptacle includes a combustion chamber delimited by a wall arrangement forming an inlet opening for the supply of fresh gas and an outlet opening for the removal of exhaust gas. The free piston apparatus includes an inflow device, which has the inlet opening and is configured such that fresh gas flowing into the combustion chamber is directed to an incident flow region in the combustion chamber arranged offset axially to the inlet opening, which incident flow region is arranged off-center relative to the axis. A method for operating a free piston apparatus includes operating an inflow device which has an inlet opening configured such that fresh gas is directed to an incident flow region in a combustion chamber offset axially to the inlet opening.