Abstract: A sliding mechanism of the present invention includes a cylinder bore having a thermally sprayed iron-based coating and includes a piston with a piston ring covered with a hard coating composed mainly of carbon. The thermally sprayed coating has diamond abrasive grains. An area ratio of the diamond abrasive grains to a surface of the thermally sprayed coating is 0.3 to 1.8%, which enables suppressing wear of the piston ring having the hard coating composed mainly of carbon.

Abstract: A piston may have an annular body including a crown portion defining a longitudinal axis, a radial direction perpendicular to the longitudinal axis, a plane containing the longitudinal axis and the radial direction, and a contoured combustion bowl. In the plane containing the longitudinal axis and the radial direction, the crown portion includes a radially outer squish surface, and a swirl pocket having a reentrant surface that extends axially downwardly and radially outwardly from the squish surface defining a tangent that forms a reentrant angle with the squish surface that ranges from 33.0 degrees to 37.0 degrees.

Abstract: A piston ring (10) has a running surface (12) and a flank surface (14) which are coated. The uppermost layer of the running surface (12) is a hydrogen-containing or a hydrogen-free DLC layer, and the uppermost layer of at least one flank surface (14) is a chromium layer. A method of producing a piston ring (10) includes forming a DLC layer as the uppermost layer of the running surface (12), and forming a chromium layer as the uppermost layer of at least one flank surface (14).

Abstract: Provided is an engine, including: a cylinder including a cylinder liner; a piston provided inside the cylinder liner; a piston ring provided on the piston; a contact detector configured to detect a contact between a step formed in an inner peripheral surface of the cylinder liner and the piston ring; and a compression ratio controller configured to control a top dead center position of the piston so that the piston ring at the top dead center position is located on a combustion chamber side with respect to the step when the contact is detected.

Abstract: A piston in which a solid lubricant resin layer made of a resin containing a solid lubricant is formed at a skirt portion. A guide groove absent area where no guide groove is formed, which is provided in a predetermined range of the solid lubricant resin layer at a center portion in a width direction. The guide grooves directing from the both ends in the width direction of the guide groove absent area to both ends in the width direction of the skirt portion. The end portions of the guide grooves extended to end edges of the solid lubricant resin layer to form open ends. The solid lubricant resin layer and the guide grooves are formed at least at a thrust side skirt portion. The guide grooves are formed in a shape inclined upward from the guide groove absent area toward the end edges of the solid lubricant resin layer.

Abstract: A cylinder block includes a body part where a cylinder is formed, an outer wall part made of fiber reinforced resin and surrounding an outer circumference of the body part, and a metal member attached to the outer wall part. The outer wall part is comprised of an inner layer surrounding the outer circumference of the body part, and an outer layer surrounding an outer circumference of the inner layer. A density of reinforcing fiber contained in the outer layer is higher than a density of reinforcing fiber contained in the inner layer. The metal member is attached to the outer wall part so as to contact the outer layer. The reinforcing fiber contained in the outer layer has an electric insulating property.

Abstract: A cylinder block includes a metal body part having a cylinder, and an outer wall part made of fiber reinforced resin, surrounding an outer circumference of the body part. A part of the outer wall part at BDC side in a cylinder axis direction contacts a bottom wall forming part. The outer wall part is comprised of an inner layer surrounding the outer circumference of the body part, and an outer layer surrounding an outer circumference of the inner layer. A density of reinforcing fiber contained in the outer layer is higher than that in the inner layer. A thickness of a part of the inner layer at BDC side in the cylinder axis direction is greater than that of the TDC-side inner layer. A thickness of a part of the outer layer at TDC side in the cylinder axis direction is greater than that of the BDC-side outer layer.

Abstract: An internal combustion engine includes an auxiliary chamber bulkhead, the auxiliary chamber bulkhead including: a peripheral wall portion that is inserted in a vertical hole extending from a combustion chamber along a reference axis and that is in contact with an inner wall of the vertical hole about the reference axis; and a bottom wall portion that is continuous from the peripheral wall portion and that bulges from the vertical hole toward the combustion chamber, the peripheral wall portion and the bottom wall portion defining an auxiliary chamber that communicates with the combustion chamber. An ignition plug is disposed above the peripheral wall portion along the reference axis. A fuel injection valve is disposed in a position inclined with respect to the reference axis toward an opening formed in an inner surface of the peripheral wall portion.

Abstract: The bore of the ring has workings suitable to act as a grease reserve at a friction area. A self-lubricating coating layer with a low wettability is applied to the entire surface of the bore, including in the workings suitable to act as a grease reserve, such that after wearing of the layer of self-lubricating coating at the friction surface of the bore, the difference in wettability between the friction surface and the workings still having the coating layer, enables the grease to be drawn out of the workings in order to lubricate the friction area.

Abstract: An internal combustion engine includes an engine main body defining a cylinder bore, a piston received in the cylinder bore, and a crankshaft rotatably supported by the engine main body and connected with the piston via a connecting rod, the piston including a skirt. The cylinder bore includes a first region defined as a range along the cylinder axial line on a side of a top dead center from a first piston position, and a second region defined as a range along the cylinder axial line on a side of the bottom dead center from a second piston position closer to the bottom dead center than the first piston position, and a connection region positioned between the first and second regions. A diameter of the cylinder bore is smaller in the first region than in the second region, and the connection region connects the first and second regions smoothly.

Abstract: A universal device for capping and mounting a motor within a motorized pool cleaner housing that allows a motor pump to be installed in different brands of pool cleaners and used at increased depths underwater. An improved motor can seal has an outer seal having a first diameter, an inner seal having a second diameter and an intermediate seal connecting the outer seal to the inner seal where the inner seal is tapered towards the distal end of the inner seal. An improved motor shaft is used having a head section, a body section and a seal area, wherein the seal area is hard chrome plated.

Abstract: A method of applying a PTFE (polytetrafluoroethylene) solution includes a dispersion step of dispersing a diamond powder in an organic solvent using bead milling to manufacture a dispersion solution, a mixing step of mixing a silane solution with the dispersion solution to manufacture a mixture solution, an addition step of adding the PTFE solution including PTFE particles having a size of 0.1 to 6 ?m to the mixture solution to manufacture a coating solution, a coating step of applying the manufactured coating solution on a surface of a piston skirt to form a coated layer including a plurality of dimples distributed thereon, and a curing step of drying and heat-treating the coated layer.

Abstract: An engine block, an automotive structure, and a method of coating an inner surface of an engine cylinder bore of an engine cylinder are provided. The method includes providing an inner bore substrate defining an inner surface of the engine cylinder bore, the inner bore substrate being formed of a first material. The method further includes disposing a thermal spray coating onto the inner surface of the engine cylinder bore. The thermal spray coating is formed of a second material that is different than the first material. The method also includes melting at least a portion of the thermal spray coating with a laser after performing the step of disposing the thermal spray coating onto the inner surface of the engine cylinder bore. The automotive structure and the engine block have a substrate covered by a thermal spray coating and laser remelted sections anchoring the coating to the substrate.

Abstract: Provided is an oil ring. A shape of an outer peripheral surface of an upper segment arranged on an engine combustion chamber side has a symmetrical curved shape. A shape of an outer peripheral surface of a lower segment arranged on a side away from the engine combustion chamber is a symmetrical curved shape.

Abstract: An improved surface activation technique improves the adhesion of thermal spray coatings, which is useful for engine cylinder bores. The new method includes compressing the cylinder bore surface to create a surface profile on the surface, such as through rolling a roller along the surface. An engine block is also provided, which includes a plurality of cylinder bores, each cylinder bore having an inner surface, and each inner surface having a surface profile that includes a helical groove and other surface profiles formed in the inner surface. A thermal spray coating is formed on the inner surface of each cylinder bore, the thermal spray coating being adhered to the surface profile of the inner surface. A roller assembly for activating the surface is also provided.

Abstract: A method of applying a PTFE (polytetrafluoroethylene) solution includes a dispersion step of dispersing a diamond powder in an organic solvent using bead milling to manufacture a dispersion solution, a mixing step of mixing a silane solution with the dispersion solution to manufacture a mixture solution, an addition step of adding the PTFE solution including PTFE particles having a size of 0.1 to 6 ?m to the mixture solution to manufacture a coating solution, a coating step of applying the manufactured coating solution on a surface of a piston skirt to form a coated layer including a plurality of dimples distributed thereon, and a curing step of drying and heat-treating the coated layer.

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 second heat-shielding film 20 produced by anodizing treatment of both surfaces of pure Al foil with an Al purity equal to or larger than 99.0% is disposed on a surface of a first heat-shielding film 12 that is formed by anodizing treatment of a surface of a combustion chamber configuring component 10 formed from an Al alloy (Al purity of less than 99.0%) as a based material. A heat resistant adhesive is poured from between these heat-shielding films, and the heat resistant adhesive is heated and cured (an intermediate layer 22). Since the second heat-shielding film has low surface roughness Ra of an average of approximately 1.0 ?m even in an unpolished state, polishing or the like for the film with an objective of smoothing after bonding of the second heat-shielding film can be omitted. Further, the heat-shielding film structure with a smoothed surface can be provided.

Abstract: A piston for an engine is provided, that makes it possible to improve supply of engine oil to a recessed part thereof. The piston includes a resin coating film and a recessed part on a surface of a skirt part. In the piston, resin coating films are distributed in a patchy fashion on the surface of the skirt part. The recessed part is formed by the surface of the skirt part, between adjacent surfaces of the patchy resin coating films and by the adjacent resin coating films, forming a net-like groove. An outer-edge resin coating film, extending in a piston movement direction, is provided at the ends, in a piston circumferential direction of the skirt part.

Abstract: A ducted combustion system for an internal combustion engine includes a combustion chamber, a fuel injector, and a plurality of ducts. The combustion chamber is defined between a flame deck surface of a cylinder head and a piston crown of a piston disposed within a cylinder bore. Further, the fuel injector is configured to inject fuel into the combustion chamber as a plurality of fuel jets. The plurality of ducts is disposed within the combustion chamber between the flame deck surface and the piston crown. The plurality of ducts is disposed such that each of the plurality of fuel jets at least partially enters one of the plurality of ducts. The at least one of the plurality of ducts is configured to move to vary an angle of a corresponding at least one of the plurality of fuel jets relative to a longitudinal axis of the fuel injector.

Abstract: A pump piston is disclosed. The pump piston may include a body having an actuating end, a pressurizing end opposite the actuating end, and an outer diameter that is greater at the pressurizing end than at the actuating end, wherein the outer diameter varies between the pressurizing end and the actuating end without increasing to form an outer diameter profile.

Abstract: Method and apparatus for controlling the volume of air or air and non-combusted fuel mixture inside a combustion chamber and cylinder of an internal combustion engine. The apparatus includes an inlet-outlet portal having open and closed states and connected to air or air and non-combusted fuel source(s), and a combustion chamber with reduced volume. The inlet-outlet portal is controlled, when open, to permit air or air and non-combusted fuel mixture to enter or enter and exit the combustion chamber and cylinder and when closed to prevent air or air and non-combusted fuel mixture from entering or exiting the chamber and cylinder, in which the volume of air or air and non-combusted fuel mixture located inside the chamber and cylinder when the inlet-outlet portal closes, is less than the volume of the combustion chamber and cylinder defined when the piston is at the bottom dead center position inside the cylinder when the inlet-outlet portal is closed.

Abstract: A ducted combustion system is disclosed. The ducted combustion system includes a combustion chamber bound by a flame deck surface of a cylinder head of an internal combustion engine and by a piston top surface of a piston disposed within the internal combustion engine. The system includes a fuel injector including one or more orifices, the one or more orifices injecting fuel into the combustion chamber as at least one fuel jet. The system includes at least one duct disposed within the combustion chamber between the flame deck surface and the piston top surface, the at least one duct including one or more structural tabs proximate to an outlet of the at least one duct and being disposed such that the at least one fuel jet, at least partially, enters one of the at least one duct upon being injected into the combustion chamber.

Abstract: A piston for an engine includes a skirt part, and a resin coating film and a recess formed on a surface of the skirt part. A plurality of the resin coating films are discretely arranged in spots on the surface of the skirt part, and a mesh-like groove is formed by the recess provided between the resin coating films. The recess formed on the skirt part between the resin coating films adjacent to each other in a piston circumference direction is set to be adjacent to another resin coating film in a piston moving direction. An end part of the resin coating film in the piston moving direction is formed in a concave shape when seen in a piston radius direction.

Abstract: A piston system includes a piston housing having a cylindrical body and forming an opening; a piston head positioned within and slidingly engaged with the opening; a first conduit extending from a side of the piston head to a top surface of the piston head; a first pocket extending partially within the cylindrical body of the piston housing.

Abstract: The disclosure describes multipoint ignition systems for an engine and methods of operation of the same. The systems and methods can include an engine, including an engine block having at least one cylinder bore, a piston having a piston crown facing a flame deck surface such that a combustion main chamber is defined within a cylinder bore and located between the piston crown and the flame deck surface, the piston crown further including a piston bowl having a generally concave shape, and a combustion pre-chamber having a nozzle tip disposed in fluid communication with the combustion main chamber, the nozzle tip having at least one nozzle opening configured to inject a fuel jet into the combustion main chamber, wherein the piston includes a piston wall located around a circumference of the piston bowl, the piston wall including at least one cavity.

Abstract: A piston for an internal combustion engine has an upper crown portion with a pair of pin bosses depending therefrom, wherein the pin bosses have pin bores axially aligned along a central pin bore axis. A pair of laterally spaced skirt portions are fixedly attached to the pin bosses and depend to a lowermost free edge. At least one of the skirt portions has a recess extending upwardly from the lowermost free edge beyond the central axis of the pin bores.

Abstract: A piston for an internal combustion engine includes a piston body. The piston body includes a head, two side walls, two skirts, and a reinforcement member. The head includes a recessed crown. Each side wall includes a pin boss configured to support a piston pin. The two skirts are respectively located at a thrust side with respect to an axis of the piston pin and an anti-thrust side with respect to the axis of the piston pin. The reinforcement member includes two legs and a connecting portion connecting upper ends of the two legs. The two legs are respectively insert-casted in the two skirts. The connecting portion is insert-casted in the head.

Abstract: A pivot bearing suitable for two connecting rods in at least one piston of an internal combustion engine having two crankshafts, includes radial bearing regions that are provided with bolt boreholes and are disposed on either side of a center longitudinal plane of the piston and delimit connecting rod ends, forming an intermediate space. The bearing regions are designed as cylinder bodies having a crucible-like cross-section, of which each cylinder body has a base wall and a bearing ring jacket. The base walls of the two cylinder bodies extend at a distance from each other, and the bearing ring jackets surrounding the base walls are guided away from the base walls in opposite directions. One or more connecting supports run between the base walls. The bearing ring jackets cooperate with the piston boreholes in a rotatably movable manner. The base walls are connected to bearing bushings which are oriented in the axial direction of the pivot bearing and into which the bolt boreholes are incorporated.

Abstract: A piston capable of withstanding high temperatures and extreme conditions of a combustion chamber of an internal combustion engine and manufactured with reduced costs is provided. The method of manufacturing the piston includes casting or forging the bulk of the piston as a single-piece with an open cooling gallery from an economical first material, such as steel, cast iron, or aluminum. The method further includes forming a portion of a combustion bowl surface, which is a small area of the piston directly exposed to the combustion chamber, from a second material by additive machining. The second material has a higher thermal conductivity and higher resistance to oxidation, erosion, and oil coking, compared to the first material. The additive machining process is efficient and creates little waste, which further reduces production costs.

Abstract: Various methods and systems are provided for a combustion system of an engine. In one example, a combustion system comprises a piston crown bowl with a central apex, a combustion chamber operable at a compression ratio in a range of from about 13:1 to about 17:1, the combustion chamber formed at least partially by the piston crown bowl, and a fuel injector with a nozzle extending into a central portion of the combustion chamber that is operable to inject fuel directly into the combustion chamber, the nozzle defining a number of apertures that is in a range of from six to ten.

Abstract: To provide a combination of a cylinder made of a hypereutectic Al—Si alloy and a hard-carbon-coated piston ring both exhibiting excellent wear resistance, the piston ring is provided with a laminate coating at least on an outer peripheral sliding surface thereof; the laminate coating comprising a metal layer, a metal-containing, hard carbon layer, and a metal-free, hard carbon layer in this order from the substrate side; the laminate coating having Martens' hardness (indentation hardness) HMs of 5-13 GPa, indentation modulus E of 70-200 GPa, and a deformation ratio Rpe of 0.45 or less, which is expressed by a ratio (Wp/We) of plastic deformation energy Wp to elastic deformation energy We; and a ratio (Tmf/Tm) of the thickness Tmf of the metal-free, hard carbon layer to the thickness Tm of the metal-containing, hard carbon layer being 2-8.

Abstract: A piston for an internal combustion engine includes a piston main body for the internal combustion engine, and a crosshatched groove being formed on a surface of the piston main body. The crosshatched groove includes a crosshatch angle that corresponds to a crossing angle of lines that configure a crosshatch, the crosshatch angle that is set at a range from equal to or greater than 15 degrees to equal to or less than 35 degrees.

Abstract: A method of increasing wear resistance of one or more part(s) of a rotating mechanism includes manufacturing the one or more part(s) with a portion thereof configured to be exposed to wear during fluid flow associated with the rotating mechanism having a dimension different from that of a desired dimension, applying a protective coating of an aluminum bronze alloy to the portion through welding deposition, and mechanically treating the protective coating. The method also includes applying one or more layer(s) of solid-alloy over the protective coating through electro-erosion deposition, and continuing the mechanical treatment of the protective coating and/or the one or more layer(s) of solid-alloy after the solid-alloy deposition to obtain the desired dimension of the portion.

Abstract: An opposed piston engine includes at least one cylinder with a bore surface and longitudinally-spaced exhaust and intake ports that open through the sidewall of the cylinder. A pair of opposed pistons is disposed in the cylinder for sliding movement along the bore surface. An oil-retaining surface texture pattern in an interface between the pistons and the bore surface extends in a longitudinal direction of the cylinder, aligned with bridges of at least one port. The surface texture pattern includes a plurality of separate recesses on an outside surface of a skirt of each piston. Alternatively, or in addition, the surface texture pattern includes a plurality of separate recesses extending in a longitudinal direction of the cylinder, aligned with bridges of at least one port.

Abstract: A low friction coating for an internal combustion engine and a method of forming a low friction surface on at least one of the engine's friction-sensitive components. In one form, a solid lubricant precursor additive is combined with motor oil such that upon work being performed on the combination by adjacently-interacting engine components, the solid lubricant tribochemically reacts to form a friction-reducing coating or film. In one preferred form, the coating or film is triboformed on a cylinder bore or a liner configured to fit within the bore. The reciprocating movement between the cylinder or liner and a piston and/or piston rings promotes in-situ formation of the layer after the engine has already been manufactured rather than during engine fabrication or assembly.

Abstract: An engine operable using flash steam expansion comprising one or more cylinders each having a piston and one or more water injection ports, the pistons driven by flash steam expansion when injected water rapidly change state from liquid to gas. Another engine operable in an internal combustion mode and a flash steam expansion mode comprising one or more cylinders having a piston, an air intake port and valve, and first and second exhaust ports and valves, first, second, and third cam shafts, wherein the engine is selectably operable in a four-cycle mode or a two-cycle mode. A method of operating an engine in a four-cycle internal combustion mode and a two-cycle flash steam expansion mode comprising the steps of using internal combustion in a four-cycle sequence, detecting when a temperature of the engine reaches a predetermined temperature; and terminating internal combustion and using flash steam expansion in a two-cycle sequence.

Abstract: Disclosed is an engine that comprises an engine block, and the engine block comprises a cylinder. The engine further comprises a cylinder head mounted to the engine block, and the cylinder head comprises an intake valve seat and a shroud. Further yet, the engine comprises a combustion chamber formed at least partially by the cylinder and the cylinder head. The intake valve is configured to travel between a fully closed position seated against the intake valve seat and an opened position displaced from the intake valve seat, thus allowing intake flow through the intake valve seat into the combustion chamber. The shroud only partially surrounds a periphery of the valve and extends along at least a portion of the travel of the intake valve so as to restrict intake flow along only a portion of the intake valve.

Abstract: A combination of a cylinder 62 of an internal combustion engine and a piston ring 40 for sliding an inner periphery of the cylinder, wherein at least a sliding face of the cylinder is composed of an aluminum alloy including 8 mass % to 22 mass % of Si and at least one or more particles selected from the group consisting of Si, Al2O3 and SiO2 particles each having a diameter of 3 ?m or more, and at least an outer periphery of the piston ring is coated with a hard carbon coating 14 composed only of hydrogen and carbon.

Abstract: A sliding body for an internal combustion engine may include a main part and a coating which at least partially covers the main part. The coating may have a first main layer. The first main layer may include main components which are molybdenum, nitrogen and oxygen.

Abstract: A galleryless piston for an internal combustion engine and method of construction thereof are provided. The piston has a monolithic piston body extending along a central longitudinal axis. The piston body has an upper wall forming an upper combustion surface with first and second portions, with the first portion extending annularly along an outer periphery of the upper wall and the second portion forming a combustion bowl. The upper wall has an undercrown surface on an underside of the combustion bowl directly opposite the second portion of the upper combustion surface. The undercrown surface has an openly exposed 2-dimensional surface area, as viewed looking along the central longitudinal axis, between about 35-60 percent of an area defined by a maximum outer diameter of the piston body, thereby providing an expansive area against which oil being splashed or sprayed can freely contact to cool the piston.

Abstract: The present invention provides a piston for a spark-ignition engine, comprising: a land part 18, an upper surface part of which has a crown part 26 forming a combustion chamber; a pair of skirt parts 20 extending downward from a peripheral part of the land part 18 and facing each other in a radial direction thereof; a pair of sidewall parts 19 coupling side end parts of the pair of skirt parts 20 to each other; and a pin boss part 21 that is formed in each of the sidewall parts 19. The present invention can inhibit the generation of HC produced at the time of combustion, while thermally protecting a top ring 30 fitted into a top ring groove 24a on an outer circumferential surface of the land part 18. The crown part 26 is configured by a flat base surface 27 and a bulging part 15 bulging upward above the base surface 27, and a thinned part 40 provided in the land part 18 is formed deep such that the deepest part thereof is positioned inside the bulging part 15.

Abstract: A piston assembly includes a piston having a crown with an upper combustion surface with a cylindrical outer surface extending downwardly from the upper combustion surface. A pair of pin bosses depends from the crown to a pair of pin bores having generally cylindrical bearing surfaces aligned along a pin bore axis with a top wall portion extending between the pin bosses. The top wall portion has a concave bearing surface forming a continuous concave bearing surface with the pin bores. A separate skirt is fixed to the piston against relative movement. At least one rib extends upwardly from the top wall portion of the piston on opposite sides of the pin bore axis to a lower wall surface of the crown. The at least one rib joins the crown to the top wall portion to provide structural support to the top wall portion against unwanted deflection.

Abstract: A cylinder lubrication system comprises a cylinder liner defining a cylinder, a piston reciprocally mounted in the cylinder for axial travel along a cylinder axis and having a piston skirt that moves in close proximity with the cylinder, an oil supply passage extending substantially circumferentially about an outer surface of the cylinder liner, an oil supply line fluidly connecting the oil supply passage to an oil supply, a series of small holes extending radially through the cylinder liner, from the cylinder to the oil supply passage, and operable as oil passages for lubricating oil from the oil supply to flow to the upper portion of the cylinder.

Abstract: An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one duct defined in the combustion chamber between the piston crown and the flame deck surface has a generally rectangular cross section and extends in a radial direction relative to the cylinder bore substantially along the fuel jet centerline.

Abstract: The present invention relates to a seal unit (10) suitable to be inserted in the first groove (20?) of a piston (20) of an internal combustion engine. The seal unit (10) according to the invention comprises a first ring-shaped body (10?) which defines a first gap section (12?) and a second ring-shaped body (10?) which defines a second gap section (12?). According to the invention such bodies are overlapping so that the position of said first section (12?) is different from the position of said second section (12?) in relation to a reference axis (101) to which the two bodies (10?,10?) are coaxial.

Abstract: A piston for an internal combustion engine, for example a diesel engine, including a body delimited laterally by a skirt and configured to collaborate with walls of a cylinder of axis of revolution C in which the piston can slide along the axis C, the piston including a transverse face including a central pip, a peripheral ring, and a bowl of axis of revolution B that extends from the central pip towards the peripheral ring to which it connects at a lip of thickness Ep, the bowl including, in substantial vertical alignment with the lip, a torus in profile, for example of dome-shaped, of maximum radius capable of guiding fuel injected under the lip in the region of a re-entrant zone towards the central pip. The tip of the central pip exhibits a flattened region centred on the axis of revolution B of the bowl, of a width Lt ranging between 0 mm and 5 mm, or substantially equal to 2.5 mm.

Abstract: An apparatus and method for a differential stroke combustion engine. The combustion engine including one or more two-part pistons, each two-part piston having a first piston part and a second piston part. The apparatus comprising: piston-lever element mechanically coupled to the second piston part; a plurality of cam-followers assemblies selectively coupleable with the piston-lever element for controlling operation of the second piston part; and wherein selective engagement of one or more cam-followers assemblies defines an operational mode of the second piston part.

Abstract: In two-stroke engines, it is common to provide two compression rings on the piston and an additional oil ring. The oil ring can be on the piston, but yields a longer piston. Alternatively, the oil ring is placed in a circumferential groove in the cylinder liner. One problem with such a configuration is that the compression rings move with respect to the oil ring and the annular volume between the two is compressed during reciprocation of the piston, which can cause pumping of oil into the ports. According to embodiments of the present disclosure, axial slots are formed in the cylinder liner that extends from the circumferential groove toward the ports extending along the bridges and beyond the ports. This provides a vent for the annular volume to avoid pumping the oil into the ports.

Abstract: To remove contaminations in the area of a fire land (6) of a piston (5) an insert is provided (1) which sweeps the outer circumference of the piston (5) upon passing the top dead center and in so doing scrapes accumulating contaminations. The insert is formed of a first annular member (2) in which a second annular member (3) is inserted in a groove (9).