Various examples are provided related to opposing piston synchronized linear machines. In one example, among others, an opposed piston synchronized linear machine includes a linear engine having opposed piston assemblies including two pistons that move linearly in opposite directions along a longitudinal axis of a central cylinder; first and second linear electromagnetic machines coupled at a proximal end to the piston assemblies; and a resonant driver assembly that provides compression during a compression stroke of the linear engine. The first and second linear electromagnetic machines can convert linear motion provided by the two pistons to electrical energy in a generating mode. The opposed piston assemblies can be synchronously controlled to generate a compression ratio sufficient to combust fuel in a combustion chamber of the central cylinder.

Various embodiments of the present disclosure provide a combustion-powered fastener-driving tool including multiple combustion chambers and/or usable with fuel canisters of varying lengths.

A load adaptive linear electrical generator system is provided for generating DC electrical power. The electrical generation system includes one or more power generation modules which will be selectively turned on or off and additively contribute power depending on the DC power demand. Each power generating module includes a pair of linear electrical generators connected to respective ones of a pair of internal combustion piston based power assemblies. The piston in the internal combustion assembly is connected to a magnet in the linear electrical generator. The piston/magnet assembly oscillates in a simple harmonic motion at a frequency dependent on a power load of the electrical generator. A stroke limiter constrains the piston/magnet assembly motion to preset limits.

A load adaptive linear electrical generator system is provided for generating DC electrical power. The electrical generation system includes one or more power generation modules which will be selectively turned on or off and additively contribute power depending on the DC power demand. Each power generating module includes a pair of linear electrical generators connected to respective ones of a pair of internal combustion piston based power assemblies. The piston in the internal combustion assembly is connected to a magnet in the linear electrical generator. The piston/magnet assembly oscillates in a simple harmonic motion at a frequency dependent on a power load of the electrical generator. A stroke limiter constrains the piston/magnet assembly motion to preset limits.

The present converter for converting reciprocating motion into rotary motion comprises a pair of rotors counter-rotating in axial alignment, said rotors having rotor magnets and auxiliary rotor magnets fastened thereon, and a pair of rods moving reciprocally in opposite directions relative to one another along the axis of rotation of the rotors, said rods having rod magnets and auxiliary rod magnets fastened thereon, wherein at least some of the rotor magnets and/or the rod magnets are arranged such that their poles are disposed on several concentric cylindrical working surfaces simultaneously.

The present converter for converting reciprocating motion into rotary motion comprises a pair of rotors counter-rotating in axial alignment, said rotors having rotor magnets and auxiliary rotor magnets fastened thereon, and a pair of rods moving reciprocally in opposite directions relative to one another along the axis of rotation of the rotors, said rods having rod magnets and auxiliary rod magnets fastened thereon, wherein at least some of the rotor magnets and/or the rod magnets are arranged such that their poles are disposed on several concentric cylindrical working surfaces simultaneously.

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 electromagnetic machine includes a stator, a translator, and a bearing system. The bearing system maintains alignment against lateral displacement of the translator relative to the stator, as the translator reciprocates axially. More particularly, the bearing system maintains a motor air gap between the stator and a magnetic section of the translator. The stator includes a plurality of stator teeth and windings, which form a plurality of phases. The stator teeth and windings are arranged using a hoop stack with spines to form a stator bore and define the motor air gap. The bearing system can include bearing housings that are configured to form a bearing interface with a surface of the translator. The bearing interface can include a contact bearing or a non-contact bearing, such as a gas bearing. Current is controlled in the phases to convert between electrical energy and kinetic energy of the translator.

A linear electromagnetic machine includes a stator, a translator, and a bearing system. The bearing system maintains alignment against lateral displacement of the translator relative to the stator, as the translator reciprocates axially. More particularly, the bearing system maintains a motor air gap between the stator and a magnetic section of the translator. The stator includes a plurality of stator teeth and windings, which form a plurality of phases. The stator teeth and windings are arranged using a hoop stack with spines to form a stator bore and define the motor air gap. The bearing system can include bearing housings that are configured to form a bearing interface with a surface of the translator. The bearing interface can include a contact bearing or a non-contact bearing, such as a gas bearing. Current is controlled in the phases to convert between electrical energy and kinetic energy of the translator.