Abstract: The present disclosure provides an open-faced piston with a circumferential groove into which a piston ring assembly is arranged. Openings at the bottom of the circumferential groove and between a front land of the open-faced piston and the piston face are provided. The openings are arranged to allow for a combustion reaction to propagate through the volume defined between the bottom of the piston ring assembly and the piston face such that at least a portion of an air and fuel mixture located in that volume is reacted.

Abstract: 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.

Abstract: The present disclosure provides a sealing ring assembly having ring segments configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. The sing segments are configured to move radially outward and wear during operation of the piston via the cylinder device. The ring segments include, for example, wedge-shaped features that engage with corresponding wedge recesses in the interfaces between ring segments. The sealing ring assembly may include a high-pressure boundary and a low-pressure boundary. As the sealing ring wears, the ring segments stay engaged with the interfaces, so that ring gaps do not form on the low pressure boundary.

Abstract: The present disclosure provides a sealing ring assembly having a ring and one or more gap cover elements, configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. The ring may be segmented, and the gap cover elements may engage with interfaces between the ring segments. The gap cover elements are configured to move radially outward and wear as the ring wears. The gap cover elements may include, for example, wedge-shaped features that engage with corresponding wedge recesses in the interfaces. The sealing ring assembly may include a high-pressure boundary and a low-pressure boundary. As the sealing ring wears, the gap cover elements stay engaged with the interfaces, so that ring gaps do not form on the low pressure boundary.

Abstract: 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.

Abstract: The present disclosure provides a sealing ring assembly having a sealing ring and a reinforcement, configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. The sealing ring may be segmented, and a metal layer, wire, or other reinforcement may be affixed to the ring. The reinforcement is placed into tension against the sealing ring, which is correspondingly placed into compression. The composite structure of a relatively brittle sealing ring and reinforcement provides for reduced tensile loads in the sealing ring, thus extending life and reducing the likelihood of failure. The brittle portion of the sealing ring assembly may include a polymer or ceramic such as graphite, which is relatively less strong in tension than compression.

Abstract: A ringset is configured to be arranged on a piston for sealing a gas in a high-pressure region of a cylinder in the absence of oil or other liquid lubricant. The ringset includes one or more rings made from a high-strength material as a sealing element. The ringset also includes a solid lubricant applicator configured to provide lubrication between the one or more rings and a bore of the cylinder. For example, the ring can support pressure loads from high-pressure gas without breaking, while the applicator need not act as a seal. As the piston reciprocates in the bore, the applicator slides against the bore and applies solid lubricant material to the bore, resulting in a solid lubricant film on the bore against which the sealing element may slide. The applicator includes a material such as a graphite, a polymer, or other suitable solid lubricant.

Abstract: 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.

Abstract: A sealing ring includes a first sealing element having a first mating surface and a second sealing element having a second mating surface. A high-pressure boundary extends across at least a portion of the first sealing element and across at least a portion of the second sealing element, and a low-pressure boundary extends across at least a portion of the first sealing element and across at least a portion of the second sealing element. The first mating surface, the second mating surface, or both, includes a recess open to the low-pressure boundary and not open to the high-pressure boundary. The recess may include a groove, for example. The first mating surface is sealed against the second mating surface by a first force acting on the first sealing element and a second force acting on the second sealing element. These forces act to pressure-lock the assembly.

Abstract: A sealing ring includes a first sealing element having a first mating surface and a second sealing element having a second mating surface. A high-pressure boundary extends across at least a portion of the first sealing element and across at least a portion of the second sealing element, and a low-pressure boundary extends across at least a portion of the first sealing element and across at least a portion of the second sealing element. The first mating surface, the second mating surface, or both, includes a recess open to the low-pressure boundary and not open to the high-pressure boundary. The recess may include a groove, for example. The first mating surface is sealed against the second mating surface by a first force acting on the first sealing element and a second force acting on the second sealing element. These forces act to pressure-lock the assembly.

Abstract: 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.

Abstract: 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.

Abstract: The present disclosure provides a sealing ring assembly having a first ring and a second ring, configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. Accordingly, the sealing ring assembly includes a high-pressure boundary and a low-pressure boundary. Each ring may be segmented, and the first and second rings interface along a surface. Along the surface at the interface, a groove open to the lower pressure region aids in pressure locking the sealing ring assembly. A pocket in the second ring allows for high pressure gas to aid in balancing radial forces on the sealing ring assembly. As the sealing ring wears, the first and second rings remain engaged with one another.

Abstract: The present disclosure provides an open-faced piston with a circumferential groove into which a piston ring assembly is arranged. Openings at the bottom of the circumferential groove and between a front land of the open-faced piston and the piston face are provided. The openings are arranged to allow for a combustion reaction to propagate through the volume defined between the bottom of the piston ring assembly and the piston face such that at least a portion of an air and fuel mixture located in that volume is reacted.

Abstract: 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.

Abstract: The present disclosure provides a sealing ring assembly having a first ring and a second ring, configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. Accordingly, the sealing ring assembly includes a high-pressure boundary and a low-pressure boundary. Each ring may be segmented, and the first and second rings interface along a surface. Along the surface at the interface, a groove open to the lower pressure region aids in pressure locking the sealing ring assembly. A pocket in the second ring allows for high pressure gas to aid in balancing radial forces on the sealing ring assembly. As the sealing ring wears, the first and second rings remain engaged with one another.

Abstract: The present disclosure provides an open-faced piston with a circumferential groove into which a piston ring assembly is arranged. Openings at the bottom of the circumferential groove and between a front land of the open-faced piston and the piston face are provided. The openings are arranged to allow for a combustion reaction to propagate through the volume defined between the bottom of the piston ring assembly and the piston face such that at least a portion of an air and fuel mixture located in that volume is reacted.

Abstract: The present disclosure provides a sealing ring assembly having a sealing ring and a reinforcement, configured to seal a high-pressure region from a lower pressure region of a piston and cylinder device. The sealing ring may be segmented, and a metal layer, wire, or other reinforcement may be affixed to the ring. The reinforcement is placed into tension against the sealing ring, which is correspondingly placed into compression. The composite structure of a relatively brittle sealing ring and reinforcement provides for reduced tensile loads in the sealing ring, thus extending life and reducing the likelihood of failure. The brittle portion of the sealing ring assembly may include a polymer or ceramic such as graphite, which is relatively less strong in tension than compression.

Abstract: The present disclosure provides a sealing ring assembly with one or more piston-integrated gap cover features, configured to seal a high-pressure region from a relatively lower pressure region of a piston and cylinder device. The sealing ring assembly may include two rings which each may include one or more ring segments. The one or more gap-cover features, which may be in the form of protrusions in the piston ring groove, may engage with corresponding flat sections of the ring segments. As the sealing ring wears, the gap-cover features may stay engaged with the ring segments, thereby maintaining a seal.

Abstract: A piston engine may include a clearance gap between a piston assembly and a cylinder. The piston may be configured to translate in a bore of the cylinder. The clearance gap between the piston assembly and the bore may be actively or passively controlled. A control system may provide one or more adjustments based on, for example, a detected temperature, pressure, flow rate, work metric, and/or other indicator. The adjustments may include, for example, adjusting a cylinder liner, adjusting a flow through a bearing element, adjusting a coolant flow, adjusting a heat pipe property, and/or other adjustments. One or more auxiliary systems may be used to provide the adjustments.