Abstract: A split-cycle engine includes: a compression chamber, housing a first piston, that induces and compresses working fluid; an expansion chamber, housing a second piston, that expands and exhausts the working fluid; and a transfer chamber, housing a third piston and a fourth piston, wherein the third piston and the fourth piston move relatively to vary a volume within the transfer chamber and to selectively fluidly couple the volume within the transfer chamber to the compression chamber and the expansion chamber. A method of operating an engine includes: inducing working fluid in a first chamber; compressing the working fluid in the first chamber; moving a first moveable boundary of a second chamber; moving a second moveable boundary of the second chamber; expanding the working fluid in the third chamber; and exhausting the working fluid from the third chamber.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A split-cycle engine includes: a compression chamber, housing a first piston, that induces and compresses working fluid; an expansion chamber, housing a second piston, that expands and exhausts the working fluid; and a transfer chamber, housing a third piston and a fourth piston, wherein the third piston and the fourth piston move relatively to vary a volume within the transfer chamber and to selectively fluidly couple the volume within the transfer chamber to the compression chamber and the expansion chamber. A method of operating an engine includes: inducing working fluid in a first chamber; compressing the working fluid in the first chamber; moving a first moveable boundary of a second chamber; moving a second moveable boundary of the second chamber; expanding the working fluid in the third chamber; and exhausting the working fluid from the third chamber.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: An engine includes a compression chamber that intakes and compresses working fluid; an expansion chamber that expands and exhausts working fluid; and a transfer chamber that receives working fluid from the compression chamber and transfers working fluid to the expansion chamber, wherein an internal volume of the transfer chamber decreases during the transfer of working fluid.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A two-stroke, opposed-piston engine with one or more ported cylinders and uniflow scavenging includes an exhaust gas recirculation (EGR) construction that provides a portion of the exhaust gasses produced by the engine for mixture with charge air to control the production of NOx during combustion.

Abstract: A piston construction with an end surface is equipped with a pattern of insulating cavities embedded in an upper end of the piston, between the end surface and interior portions of the piston that are cooled by circulating liquid coolant.

Abstract: A combustion chamber for an opposed-piston engine includes a squish zone defined between circumferential peripheral areas of opposing end surfaces of the pistons, a cavity defined by one or more bowls in the end surfaces, and at least one injection port that extends radially through the squish zone into the cavity. The cavity has a cross-sectional shape that imposes a tumbling motion on air flowing from the squish zone into the cavity.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: An engine includes a compression chamber that intakes and compresses working fluid; an expansion chamber that expands and exhausts working fluid; and a transfer chamber that receives working fluid from the compression chamber and transfers working fluid to the expansion chamber, wherein an internal volume of the transfer chamber decreases during the transfer of working fluid.

Abstract: A two-stroke, opposed-piston engine with one or more ported cylinders and uniflow scavenging includes an exhaust gas recirculation (EGR) construction that provides a portion of the exhaust gasses produced by the engine for mixture with charge air to control the production of NOx during combustion.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A two-stroke, opposed-piston engine with one or more ported cylinders and uniflow scavenging includes an exhaust gas recirculation (EGR) construction that provides a portion of the exhaust gasses produced by the engine for mixture with charge air to control the production of NOx during combustion.

Abstract: A split-cycle engine includes: a first cylinder housing a first piston, wherein the first piston performs an intake stroke and a compression stroke, but does not perform an exhaust stroke; a second cylinder housing a second piston, wherein the second piston performs an expansion stroke and an exhaust stroke, but does not perform an intake stroke; and a valve chamber housing a valve, the valve comprising an internal chamber that selectively fluidly couples to the first and second cylinders, wherein the valve and internal chamber move within the valve chamber and relative to the first and second cylinders.

Abstract: A rocking journal bearing for a two-stroke cycle engine includes a bearing sleeve having a bearing surface with a plurality of axially-spaced, eccentrically-disposed surface segments and a rocking journal having a plurality of axially-spaced, eccentrically-disposed journal segments. The rocking journal is retained for rocking oscillation on the bearing surface. Space for receiving oil is provided in the rocking journal and oil delivery outlets acting through the journal segments deliver received oil to the bearing surfaces.

Abstract: A combustion chamber for an opposed-piston engine includes a squish zone defined between circumferential peripheral areas of opposing end surfaces of the pistons, a cavity defined by one or more bowls in the end surfaces, and at least one injection port that extends radially through the squish zone into the cavity. The cavity has a cross-sectional shape that imposes a tumbling motion on air flowing from the squish zone into the cavity.

Abstract: A combustion chamber for an opposed-piston engine includes a squish zone defined between circumferential peripheral areas of opposing end surfaces of the pistons, a cavity defined by one or more bowls in the end surfaces, and at least one injection port that extends radially through the squish zone into the cavity. The cavity has a cross-sectional shape that imposes a tumbling motion on air flowing from the squish zone into the cavity. Opposing spray patterns of fuel are injected into the combustion chamber. In some aspects, the opposing spray patterns are injected along a major axis of the combustion chamber.