Abstract: A piston arrangement comprising a piston movable within a cylinder and having a stroke with a first end and a second end, wherein the piston is coupled to a crankshaft by a linkage mechanism including a toggle link which is pivotally coupled to the piston and pivotally coupled to a con-rod, wherein the toggle link has a first position corresponding to the first end of the piston stroke, a second position different to the first position also corresponding to the first end of the piston stroke, and an intermediate position between the first and second positions corresponding to the second end of the piston stroke such that the piston completes four strokes for every one revolution of the crankshaft.

Abstract: A piston capable of reducing the frictional resistance between skirt portion and a cylinder inner surface and improving fuel efficiency is provided. The invention is a piston for an internal combustion engine wherein when the piston slides along a cylinder inner surface, a high surface pressure portion occurs at a center of each skirt portion and low surface pressure portions occur at both sides of the high surface pressure portion. The high surface pressure portion of plural portions is provided with a horizontal groove. The low surface pressure portions of the plural portions are provided with an inclined groove that is inclined downward toward the high surface pressure portion and that is connected to an end portion of the horizontal groove.

Abstract: A sealing sleeve for sealing between piston and cylinder wall in internal combustion engines with a height in the direction of piston movement that is at least three times as large as its width in the radial direction of the cylinder having a pressurised annular cut out (6 in FIG. 2) in that outer surface of it that contacts the cylinder wall.

Abstract: A cylinder bore with selective surface treatment includes a longitudinal axis and a cylindrical wall extending along the longitudinal axis, the cylindrical wall including first and second end portions and a middle portion positioned between the first and second end portions, the middle portion having a greater surface roughness than at least one of the first and second end portions.

Abstract: A piston including a crown and a skirt extending generally axially away from the crown. The skirt includes a pair of opposed skirt panel portions and a band spaced away from the crown and extending generally around a perimeter of the piston. The piston further includes a pair of strut assemblies, each strut assembly including a pair of struts which converge in a radially outward direction. Each strut terminates at or adjacent to one of the panel portions.

Abstract: A piston for an internal combustion engine may include a piston head and a piston skirt. The piston skirt may have piston bosses provided with boss bores. The piston bosses may be connected to each other at running surfaces. The running surfaces may be provided at least partially with a coating which is sprayed using a cold gas method. The material of the coating may be selected from the group comprising at least one of nickel, iron, copper, nickel-based alloys, iron-based alloys, copper-nickel-tin-based alloys and copper-tin-silver-based alloys.

Abstract: An opposed-piston engine includes pistons, each piston having an annular cavity in the piston's sidewall and positioned between its crown and ring grooves to block transfer of heat from the crown to the piston body.

Abstract: A handheld work apparatus has an internal combustion engine (9, 9?, 9?) and a starter device (8). The internal combustion engine has a piston (10, 10?) which has at least one piston ring (37, 38). In order to avoid a delay when starting the engine, at least one recess is provided in the cylinder bore (26) which bridges the at least one piston ring (37, 38) in at least one position of the piston (10, 10?) and which has a distance (n, o, p) to all function openings of the engine (9, 9?, 9?) configured in the cylinder bore (26). To reduce the compression in the combustion chamber (25), the piston (10?) has only one piston ring (37) or two piston rings (37, 38) are provided having respective piston ring gaps (39, 40) defining an angle (?) which is up to approximately 45°.

Abstract: A compression ring for an engine is disclosed. The compression ring may have a cylindrical body having an outer surface, and a central opening formed within the cylindrical body and concentric with the outer surface of the cylindrical body. The cylindrical body may have a radial dimension from the central opening to the outer surface that is about 1.1 to 1.3 times as long as an axial dimension of the cylindrical body.

Abstract: A differential stroke reciprocating internal combustion engine having an engine shaft and a piston configured to reciprocate within a cylinder chamber includes an inner piston part, a piston stem coupled at a first end to said inner piston part, an outer piston part which serves as a carrier for said inner piston part and is connected to said engine shaft, wherein said inner piston part is configured to operate on a cycle different from that of said outer piston part, and a control and linkage assembly coupled to said engine at an anchor point, and said control and linkage assembly pivotally coupled at a second end of said piston stem defining a copy point, wherein said control and linkage assembly guides and defines the movement of said copy point to be substantially aligned with an axis of said cylinder chamber.

Abstract: A two stroke engine of a particular configuration can have its power output increased by running bigger pistons and using ports in the piston skirt through which to conduct compressed air within the skirt through short passages in the cylinder housing that conduct the air from within the skirt to above the piston. As a result a larger piston can be used for the same spacing and opening size in the block to save the need to redesign the block and the crankshaft. A position adjuster for the piston moves it axially without rotation of the piston ports out of alignment with inlet ports in the housing. The piston rod is held in the crosshead using a flat to prevent rotation while an adjuster nut that is turned creates axial movement in the piston rod with a lock nut securing the final piston position.

Abstract: A modified piston for a reciprocating engine, the piston having a piston face that comprises a plurality of radially-oriented grooves. Each groove comprises a distal end proximate a periphery of the piston face and a proximal end proximate a center of the piston face. The width of the distal end of each groove is greater than the width of the proximal end of the groove. The depth of the distal end of each groove is greater than the depth of the proximal end of the groove. The proximal end of each groove terminates in a point.

Abstract: An engine cylinder with a piston and at least one, preferably two or four, cam-operated valves leading to the combustion chamber. A valve seat of the valve is formed in the cylinder wall immediately laterally adjacent to the cylinder bore or to the cylinder chamber. The valve axis and the cylinder axis enclose an acute angle A of 5°?A?25°, preferably 10°?A?20°. The axis of the inlet channel or the outlet channel leading to the valve seat in a plane defined by the valve axis and the cylinder axis is inclined at an angle B of 25°?B?65°, preferably 40°?B?50° to the valve axis.

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 combustion chamber in an engine includes a piston and an injector with plurality of orifices arranged to inject spray/flame plumes, which impinge on a piston outer bowl section during most of the injection. Between spray/flame plume impingement areas and in a plane substantially perpendicular to reciprocal piston movement are arranged a first type of protrusions protruding into the combustion chamber, having a smooth form for preserving kinetic energy in the flame and for redirecting circumferential flame progress mainly towards a center axis of the piston with minimal flame-to-flame interaction. A second type of protrusions are arranged in the impingement areas, being adapted for redirecting flame progress into a circumferential flame progress direction in a plane substantially perpendicular to the reciprocal piston movement and with minimal flame-to-piston wall interaction and minimal kinetic energy loss.

Abstract: A semifinished product blank, suitable for the production of a steel piston (1) for internal combustion engines having cylinder crankcases made of light metal alloys. Such a steel piston (1) has at least one upper piston part (4) which has a combustion recess (2) and an annular wall (3), and a lower piston part (4?) which has a piston skirt (5) and a connecting rod bearing (6). The semifinished product blank is made of an austenitic steel, that is stabilized with Ni, Mn and N and that has a thermal expansion coefficient in a range of 16 to 21×10?6 K?1. Also disclosed is a steel piston, which at least has a piston skirt (5) made of an austenitic steel that is stabilzed with Ni, Mn, N. The piston skirt (5) has a thermal expansion coefficient in a range of 16 to 21×10?6 K?1.

Abstract: A piston engine may include a piston assembly, which may include a piston having a self-centering feature. The piston assembly may be configured to translate in a bore of the cylinder, and contact a combustion section and/or gas driver section. The self-centering feature may use a flow of blow-by gas in a clearance gap to provide a self-centering force on the piston assembly. The self-centering feature may include one or more slotted pockets, a step, a tapered portion, any other suitable feature, or a combination thereof. Optionally, a piston assembly may include a feature that aids in self-centering such as, for example, a labyrinth 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.

Abstract: An internal combustion engine includes a power cylinder having a power chamber delimited by a power piston, the power chamber having an intake valve and an exhaust valve, a compression cylinder having a compression chamber delimited by a compression piston, the compression chamber having a fresh charge intake valve, and a flow-through chamber delimited by a flow-through piston and fluidly connected with the compression chamber via a flow-through passage. The flow-through chamber is directly or indirectly connected with the power chamber via a push-out passage. A flow-through valve is disposed in the flow-through passage. A cooler is arranged so as to cool compressed fresh charge flowing through the first flow-through passage. The pistons and the valves are movable such that the cooled, compressed fresh charge is pushed over by the compression piston from the compression chamber into the first flow-through chamber and is ultimately pushed out into the power chamber.

Abstract: In an engine, blow-by is substantially eliminated and friction is significantly reduced using one or more combinations of non-metallic rings. By substantially eliminating blow-by and by reducing friction, certain engine parameters may be changed. In addition, by substantially eliminating blow-by and by reducing friction, pollution may be reduced, fuel economy may be increased and power may be increased.

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 for internal combustion engines, having a series of conical openings at the center of each skirt section, each conical opening being horizontally located one to another and each conical opening in one skirt section aligned to another conical opening at the opposite skirt section. Each conical opening is also aligned to an oil drain hole at the oil groove located at the crown of the piston and having the external diameter larger that its internal diameter. Once installed, said conical openings forms an internal storing unit, wherein the oil or lubricant is stored and distributed constantly after being squirted out from the rod bearing to the piston, allowing the formation of a continuous lubricant film, without reducing the strength of the piston structure.

Abstract: A linerless engine includes a casting defining a bore having an inner surface and a central longitudinal axis. The casting is formed from a castable aluminum-silicon alloy including silicon particles present a range of from about 11 to about 12.5 parts by weight. The inner surface has a surface variation defined by at least some of the silicon particles protruding toward the axis for from about 0.6 to about 1.5 microns. The linerless engine includes a piston slideably disposed within the bore and configured for translating along the axis, wherein the piston is formed from an aluminum alloy and includes a body having a skirt portion coated with a first coating, and at least one ring encircling and in contact with the body. The ring is coated with a diamond-like coating that is free from degradation when in contact with the at least some of the silicon particles.

Abstract: There is provided an engine in which sliding surfaces of a cylinder and a piston do not tend to seize and the ratio of a lubricating oil to a composite fuel can be reduced. There is also provided a piston that allows the lubricating oil to be intentionally supplied to the surface of the piston that slides along the cylinder or a cylinder liner. In an aspect of the present invention, an engine in which an air-fuel mixture containing a lubricating oil is supplied into a combustion chamber includes supply means for supplying the air-fuel mixture to the interface between an inner wall of a cylinder or a cylinder liner and a tubular portion of a piston (portion between piston rings and/or piston ring portion). The supply means is, for example, through holes passing through the tubular portion of the piston and groove portions.

Abstract: An internal-combustion engine comprised of a cylinder with at least one piston which is moving to and fro in it, and a piston rod (6), which transforms the piston's movement to rotary motion in a crank shaft (9), and including equipment for a forcible stabilization of the piston axle. Each small end of the piston rods has an additional part (6g) at its right side, to produce an additional torsional moment with the aid of inertial forces. This part is characterized by its optimized form; the piston rod's big end (6f) includes the additional parts (6m), (6n), also at its right side; In this way, the force vectors and the torsional moment of the motor are optimized due to the effect of the inertial forces and the mass of the entire piston rod may be used to increase the inertial forces, which results in a considerable improvement of the economic and ecological properties of internal-combustion engines and other piston engines.

Abstract: The present invention generally relates to a recess in the top of a piston. More particularly, the present invention relates to a crescent-shaped recess in the top of an expansion piston of a split-cycle engine.

Abstract: A piston 2 includes a piston upper body 8 made up of a crown portion 3 for receiving combustion pressure and a land portion 7 having piston ring grooves 4, 5, and 6, as well as a skirt portion 9 formed on the lower side of the piston upper body 8, and a pin boss portion 11 for supporting a piston pin 10. The land portion 7 also includes an outer peripheral surface 16 of the aforementioned piston upper body 8. The land portion 7 is referred to as the outer peripheral surface 16 of the piston upper body 8. In the piston 2, reference numeral 12 denotes a thrust side, and reference numeral 13 denotes an anti-thrust side. The piston 2 is formed such that the piston upper body 8 is off-centered toward the anti-thrust side 13 with respect to a center line 14 of the piston 2.

Abstract: A piston-type internal combustion engine is formed of a high performance synthetic resin material. The cylinders and pistons have an octagonal profile. Two or three rows of pin roller bearings are positioned in transverse semi-cylindrical grooves formed on the cylinder walls, to afford smooth, low-friction rolling contact and to seal the compression from leaking around the piston. There are angle support pieces fitted within the annular channels at respective vertices or corners, and are adapted for rotationally supporting the ends of adjacent pin roller bearings.

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: A reciprocating engine 1 includes an annular top ring 5 serving as a first piston ring disposed adjacent to a top surface (head end surface) 4 of a piston 3 defining a combustion chamber 2; an annular second ring 6 serving as a second piston ring disposed with the top ring 5 interposed between the annular second ring 6 and the top surface 4; an annular gas chamber 7 defined by the top ring 5 and the second ring 6; and a plurality of communicating passages 8 for allowing the annular gas chamber 7 and the combustion chamber 2 to communicate with each other. The top ring 5 and the second ring 6 are respectively inclined with respect to an X direction in which the piston 3 reciprocates, so as to be located further away from each other on a thrust side 9 than on an anti-thrust side 10.

Abstract: An internal-combustion engine comprised of a cylinder with at least one piston which is moving to and fro in it, and a piston rod (6), which transforms the piston's movement to rotary motion in a crank shaft (9), and including equipment for a forcible stabilization of the piston axle. Each small end of the piston rods has an additional part (6g) at its right side, to produce an additional torsional moment with the aid of inertial forces. This part is characterized by its optimized form; the piston rod's big end (6f) includes the additional parts (6m), (6n), also at its right side; In this way, the force vectors and the torsional moment of the motor are optimized due to the effect of the inertial forces and the mass of the entire piston rod may be used to increase the inertial forces, which results in a considerable improvement of the economic and ecological properties of internal-combustion engines and other piston engines.

Abstract: An internal combustion engine is provided having a cylinder case with at least one cylinder bore wall defining at least one cylinder bore. At least one piston is reciprocally movable within the at least one cylinder bore. The at least one piston includes at least one skirt portion preferably having a barrel-shaped profile. The cylinder bore wall has an oleophobic characteristic, while the at least one skirt portion has an oleophilic characteristic. The oleophobic and oleophilic characteristic is produced by at least one of coating and machining the at least one cylinder bore wall and the at least one skirt portion, respectively.

Abstract: In an opposed piston engine, a pair of pistons are disposed in opposition in the bore of a cylinder. The cylinder includes first liquid coolant grooves having a first cooling capacity to cool a portion of the cylinder extending from a central portion toward an exhaust port, and second liquid coolant grooves having a second cooling capacity, less than the first cooling capacity, to cool a portion of the cylinder extending from the central portion toward an inlet port. Each piston includes a cylindrical skirt with a crown and an open end opposite the crown, a piston rod with a bore, a first end attached to a back surface of the crown, and a second end extending through the open end of the skirt, a radial array of liquid coolant flow passages in communication with the bore and disposed between the first end and the back surface of the crown, and a single wristpin retained on the second end section of the piston rod and positioned externally to the piston.

Abstract: An internal combustion engine having a piston reciprocating in a cylinder between TDC and BDC positions to influence a drive shaft. The drive shaft is associated with an expandable piston rod extension which in turn attaches to a piston rod to connect the piston with the drive shaft. The piston rod extension's length may increase and decrease in accordance with the angular position of the drive shaft. The increasing and decreasing length is governed by a guide pin which travels within a channel formed by a portion of the engine block. Increasing the length of the piston rod extension during the power phase of the engine increases the available torque of the engine without any alteration of the displacement. The assembly may also include a counterweight, which itself may travel along an eccentric path generally equal and opposite to the eccentric path along which the piston rod extension guide travels.

Abstract: An improved configuration for internal combustion engine that reduces side forces on pistons during the engine cycle. The improvement is an intermediate and guided bridge element located between pull rods and pistons with articulated connections that allow side forces to be dissipated away from the pistons.

Abstract: An engine piston is manufactured by assembling an outer shell, comprising a crown and tubular side wall in which a ring groove region and skirt are defined, with a plate-like mounting member and bonding them together by brazing or welding. The mounting member is located within the tubular side wall displaced axially from the crown and is bonded near, but displaced radially from, its centre to the crown and at its periphery to the side wall at the end of the ring groove region. The mounting member carries gudgeon pin boss means facing away from the crown. The outer shell is formed by extrusion or the like that permits minimal wall thickness and the bonded structure is of light weight but great strength and stiffness, particularly in the ring groove region. A combustion bowl formed in the crown facilitates bonding to the mounting member and defines with the mounting member an annular cooling chamber adjacent the ring groove region and crown.

Abstract: An engine includes: a cylinder block; and a piston ring, in which the cylinder block has a cylinder liner portion formed of an aluminum-based composite reinforced by a ceramic containing at least either of a silicon carbide and an alumina, and in which the piston ring is coated with a nitride film (20) including a vanadium nitride layer (21) exposed on an outer circumferential sliding surface (17).

Abstract: A piston including a crown and a skirt extending generally axially away from the crown. The skirt includes a pair of opposed skirt panel portions and a band spaced away from the crown and extending generally around a perimeter of the piston. The piston further includes a pair of strut assemblies, each strut assembly including a pair of struts which converge in a radially outward direction. Each strut terminates at or adjacent to one of the panel portions.

Abstract: A power assembly for an internal combustion engine includes a cylinder with a circular wall defining a first inside diameter. A piston is reciprocably housed within the cylinder. An integral, unitary piston deposit scraper is formed in a portion of the circular wall of the cylinder by upsetting a portion of the metallic wall so as to configure a piston scraper with a second inside diameter which is less than the first inside diameter. The inside diameter of the piston scraper closely matches that of the outside diameter of the top land of the piston. As a result, the piston scraper removes combustion deposits from the piston each time it moves into the top dead center position.

Abstract: A connecting rod for a piston assembly includes first and second guidance members for guiding a piston assembly within a cylinder during piston stroke along a first axis. The guidance members are supported by first and second support ribs extending from a shaft of the connecting rod and include first and second sliding surfaces for contacting side walls of the cylinder. The connecting rod includes an attachment boss disposed at a first end of the shaft and defines a second axis perpendicular to the first axis. The first and second support ribs extend radially outwardly from the attachment boss and are spaced radially about the second axis by approximately 180 degrees.

Abstract: A piston and cylinder assembly for an engine is disclosed. The assembly includes a piston including an aluminum alloy piston body having a crown and a skirt extending from the crown. The skirt has an exterior surface having a surface finish in a wave form with peaks and valleys, and having a roughness total between approximately 6 and 12 micrometers, the roughness total (Rt) being defined as the difference between the highest peak and lowest valley within an assessment length. The surface finish has an approximate peak-to-peak distance between 0.17 and 0.25 millimeters within the assessment length. The exterior surface is coated with a nickel ceramic composite coating. An aluminum alloy cylinder bore is disposed in an engine block and is configured to receive the piston body. The cylinder bore has a bore surface having a roughness average (Ra) between approximately 0.09 and 0.25 micrometers. The cylinder bore may be made of a eutectic Al—Si alloy including other alloying elements.

Abstract: An internal combustion engine is provided having a cylinder case with at least one cylinder bore wall defining at least one cylinder bore. At least one piston is reciprocally movable within the at least one cylinder bore. The at least one piston includes at least one skirt portion preferably having a barrel-shaped profile. The cylinder bore wall has an oleophobic characteristic, while the at least one skirt portion has an oleophilic characteristic. The oleophobic and oleophilic characteristic is produced by at least one of coating and machining the at least one cylinder bore wall and the at least one skirt portion, respectively.

Abstract: A combination of a cylinder liner and a piston ring, wherein the cylinder liner includes, silicon: 23.0-28.0% by weight, magnesium: 0.80-2.0% by weight, copper: 3.0-4.5% by weight, iron: 0.25% by weight or less, nickel: 0.01% by weight or less, wherein surface roughness profile of the inner circumference surface has Rz=0.5 to 1.0 ?m, Rk=0.2 to 0.4 ?m, Rpk=0.05 to 0.1 ?m, Rvk=0.08 to 0.2 ?m, wherein the piston ring includes carbon: 0.6-0.7% by weight, chrome: 13-14% by weight, molybdenum: 0.2-0.4% by weight, silicon: 0.25-0.50% by weight, manganese: 0.2-0.5% by weight, and wherein carbides with the diameter of 5.0 ?m and less are 4-10%.

Abstract: A connecting rod for a piston assembly includes first and second guidance members for guiding a piston assembly within a cylinder during piston stroke along a first axis. The guidance members are supported by first and second support ribs extending from a shaft of the connecting rod and include first and second sliding surfaces for contacting side walls of the cylinder. The connecting rod includes an attachment boss disposed at a first end of the shaft and defines a second axis perpendicular to the first axis. The first and second support ribs extend radially outwardly from the attachment boss and are spaced radially about the second axis by approximately 180 degrees.

Abstract: Lower temperature combustion, which may lead to lower emissions, is accomplished by displacing air adjacent to a fuel injector nozzle. Initially, air is compressed in an engine cylinder by moving the engine piston toward top dead center. Air is displaced through a flow passage within the engine cylinder when the engine piston is in the vicinity of top dead center by moving an air displacement actuator. The air displacement actuator includes a member positioned in the combustion chamber that moves with respect to the engine housing and the piston when actuated. This movement causes air to flow through a flow passage, and fuel is injected into the turbulent compressed air flowing through the flow passage. The mixture of air and fuel are compression ignited in the engine cylinder after a brief ignition delay. Lower emissions may be achieved by bringing the air to the fuel prior to ignition, rather than attempting to bring the fuel to the air as in a typical compression ignition engine.

Abstract: A reciprocating engine comprises: a piston ring; a piston ring which defines an annular gas chamber in cooperation with the piston ring and which is adjacent to the piston ring such that a pressure-receiving area of a side surface of a piston in the annular gas chamber becomes greater on a thrust side than on a counter-thrust side of the piston; and gas passages for allowing the annular gas chamber to communicate with the combustion chamber.

Abstract: A piston for an internal combustion engine has a piston crown, a circumferential top land, and a circumferential ring belt having ring grooves, as well as having a piston skirt that has two skirt walls disposed on the major thrust side and the minor thrust side of the piston, and two box walls, set back with regard to the ring belt, that connect the skirt walls. The box walls have pin bosses with pin bores. The skirt wall disposed on the major thrust side is shorter, in a circumference direction of the piston, than the skirt wall disposed on the minor thrust side.

Abstract: A piston for an internal combustion engine is provided that comprises a piston head, onto which a piston hub and a piston skirt are formed, as well as reinforcing ribs, which extend between piston hub and piston skirt and which each comprise two portions that are curved in opposite directions.

Abstract: When a homogeneous combustion is to be executed at a lean air-fuel ratio, a tumbling flow that whirls in the cylinder descending in the cylinder bore on the exhaust valve side and ascending in the cylinder bore on the intake valve side, is intensified by the fuel that is injected from the fuel injection valve toward the exhaust valve side in the cylinder bore in the last stage of the intake stroke.

Abstract: A gas exchange control mechanism for an opposed-piston engine which opens and closes inlet and outlet slots provided in the cylinder irrespective of the position of the pistons. The opposed pistons are guided completely or partially during stroke in sliding sleeves during operation of the engine. The sleeves may reciprocate mechanically, electrically, pneumatically or hydraulically in a linear manner. The sliding sleeves are adapted to open and close gas guide channels located in the engine housing.