Abstract: A piston seat method and apparatus for a differential-stroke cycle 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: a piston seat cover operatively associated with the first piston part, the piston seat cover being adapted for abutting engagement with the second piston part; wherein, upon abutting engagement, the seat cover is adapted to move relative to the first piston part, thereby at least partially absorbing impact forces applied between the first piston part and the second piston part.

Abstract: An oil ring Ro for an internal combustion engine according to the present invention includes at least one selected from the group consisting of hard carbon, CrN and TiN that covers an outer periphery 1 of the oil ring. A radius of curvature R at an outermost portion T of the oil ring in a sliding direction is 0.3 mm or more.

Abstract: Exemplary pistons are disclosed, e.g., for an internal combustion engine. An exemplary piston includes a lower part and an upper part, whereby the lower part and the upper part define a circumferential closed cooling gallery. The cooling gallery may be provided with a gallery bottom. The piston may further include a circumferential bar positioned on the gallery bottom, the circumferential bar defining at least one coolant inlet and at least one coolant outlet extending through the bar.

Abstract: The present invention relates to a piston (10) for an internal combustion engine, comprising a piston head (11) and a piston skirt (16), with a cooling channel (15) arranged in the piston head (11) and with at least one bore (17) opening into the cooling channel (15), a conduit (18) for a cooling oil jet (A) being housed in the bore. According to the invention, a jet divider (19) is arranged at the first free end (18a) of the conduit (18) and, in the area of the second free end (18b) of the conduit (18), the outer lateral surface of conduit (18) has a contact surface (24) that lies, secured against torsion, against an inner surface (25) of the piston (10).

Abstract: A piston for an internal combustion engine comprises a sealed cooling gallery extending circumferentially around a center axis beneath a bowl rim of an upper crown. A metal-containing composition having a high thermal conductivity fills a portion of the sealed cooling gallery to dissipate heat. The metal-containing composition includes a base material having a melting temperature less than 181° C. and a plurality of metal particles having a thermal conductivity greater than the thermal conductivity of the base material. For example, the metal-containing composition can comprise copper particles dispersed in silicone oil, or copper particles dispersed in a mixture of alkali metals. During high temperature operation, as the piston reciprocates in the cylinder bore, the base material is liquid and flows throughout the cooling gallery to dissipate heat away from the upper and lower crowns.

Abstract: A multi-part piston for an internal combustion engine has a piston upper part and a piston lower part. The piston upper part comprises a piston head, a continuous fire land and a continuous ring part. The piston upper part and the piston lower part are connected together by securing means and form a continuous cooling channel. According to the invention, the connecting means connecting the piston upper part and the piston lower part are embodied as cooling elements that are arranged in the cooling channel and that are made of heating-conducting material.

Abstract: In a direct fuel-injection engine equipped with a pentroof-shaped piston, cross-sectional shapes containing a piston central axis (Lp) of a cavity recessed in a central part of the piston having a top face with the height varying in the circumferential direction are set so as to be basically identical at each position in the circumferential direction (see broken line).

Abstract: An engine component such as, for example, an engine piston or a part thereof, for instance a ring carrier or piston boss bushing, consisting of a cast iron alloy that contains zirconium as an alloy constituent in an amount by weight of at least 0.01% and up to 0.1%.

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: A piston coupled to a crankshaft via pullrods presents challenges for coupling the piston to the crankshaft because the connections are provided outside the piston. A bridge is coupled to a piston skirt at the end of the piston away from the piston crown. The bridge structure includes: a central support structure, a first projection extending outwardly from the central support structure in a first radial direction, and a second projection extending outwardly from the central support structure in a second radial direction. The central support structure is substantially hollow with a series of internal braces to yield a lightweight piston.

Abstract: An improved oil and gas seal assembly for an internal combustion engine that includes a scraper ring retained within an annular containment groove that, in several embodiments, is formed in the side wall of the cylinder and sized to allow the scraper ring to be fitted therein. The depth of the annular containment groove is sufficient to allow the scraper ring to be expanded during assembly with the piston and during engine operation when the assembly is exposed to vibration and heat variations. A resilient element surrounds the scraper ring within the annular containment groove in order to apply inward forces to the scraper ring and keep it in contact with the movable piston skirt side wall, and also in contact with at least one wall of the groove to prevent an alternative migration path for oil or combustion gases.

Abstract: An internal combustion engine piston includes a piston crown, a thrust-side skirt, an anti-thrust-side skirt, a first apron, and a second apron. The first and second aprons are connected to the thrust-side and anti-thrust-side skirts through connecting sections. Each connecting section has a thickness that gradually increases as followed from a proximal longitudinal end to a distal longitudinal end, wherein the proximal longitudinal end is closer to the piston crown, and the distal longitudinal end is closer to a distal longitudinal end of a corresponding one of the thrust-side and anti-thrust-side skirts.

Abstract: A piston/piston ring arrangement for an internal combustion engine has a piston that is provided with at least one piston ring accommodated in a ring groove, which ring has a ring gap. A spring element is disposed between the groove root of the ring groove and the piston ring, which element fills the ring gap of the piston ring. A modular unit is composed of such a piston/piston ring arrangement and a cylinder or a cylinder sleeve of an internal combustion engine.

Abstract: A cylindrical piston for internal combustion engines, comprising a piston crown and a piston base, in the piston base a hollow space being provided, and in a piston base wall forming the hollow space pinholes being provided, characterized in that the outer circumferential surface in at least the piston base at least one oil guide is provided, the direction thereof having an axial component relative to the piston axis and the oil guide extending from the piston crown in the direction of a pinhole.

Abstract: A piston for an internal combustion engine has a piston crown, a circumferential fire land, a circumferential ring part having annular grooves, and a piston skirt, which comprises two skirt walls and two box walls set back from the ring part and connecting the skirt walls in such a way that an exposed underside of the ring part is formed in the area of each of the box walls. The box walls are provided with pin bosses having pin bores. At least one support element is arranged between each exposed underside of the ring part and the box wall associated with the underside of the ring part.

Abstract: An improved piston for an opposed piston internal combustion engine is provided. The piston includes a piston body that extends along an axis from a crown portion to a skirt portion with a full piston skirt and to a pin boss portion. The piston body includes a plurality of ring grooves in the crown portion and at least one ring groove in the skirt portion. A wrist pin which has a length that is longer than a maximum diameter of the piston body is joined with the piston body at the pin boss portion and extends past the pin boss portion for receiving a pair of connecting rods on opposite sides of the piston body. The piston body is a monobloc piston body which is made of one integral piece or of multiple pieces that are welded or adhered together.

Abstract: A piston ring has a piston ring basis element, of a material having a first thermal expansion coefficient, a wear protection layer, arranged on a radially outer face of the piston ring, that is made of a material having a second thermal expansion coefficient being smaller than the first thermal expansion coefficient, and including an intermediate layer, arranged between the piston ring basis element and the wear protection layer. The intermediate layer is made of a material having a third thermal expansion coefficient, that is bigger than the first thermal expansion coefficient.

Abstract: A piston for an internal combustion engine has a piston head and a piston skirt. The piston head has a circumferential ring belt and a circumferential cooling channel. The piston skirt has a working surface assigned to its major thrust side and to its minor thrust side. A bore that proceeds from the cooling channel is provided, which ends in the working surface assigned to the major thrust side, and is disposed at an incline, in such a manner that the bore exit encloses an acute angle (?) with the center axis (M) of the piston. An opening is formed in the working surface, and a deflection surface inclined relative to the working surface is provided between the bore and the bore exit. The working surface assigned to the major thrust side has a depression which forms at least one oil capture region above the opening.

Abstract: A piston for an engine may include a piston crown, and a piston bowl recessed within the piston crown. The piston bowl includes a center portion, a cone portion, and an annular toroidal portion. The geometry of the piston bowl is designed to correspond with a fuel injection nozzle having a specific spray angle. An exemplary piston bowl may include a toroidal major diameter between about 4.645 and 4.895 inches and a toroidal minor radius between about 1.165 and 1.235 inches. The cone portion includes an angle between about 26 to 34 degrees. The compression ratio of the piston is about 17.95 to 1.

Abstract: A piston assembly and method of construction thereof for an internal combustion engine are provided. The assembly includes a piston head having an upper combustion wall with an undercrown surface and a ring belt region. The piston head has a floor with an upper surface and a bottom surface. The floor is spaced beneath the upper combustion wall in radial alignment with the ring belt region. A substantially enclosed, annular cooling gallery is bounded by the undercrown surface and the floor. A pair of pin bores depends directly from the floor of the cooling gallery. The assembly further includes a pin having ends configured for oscillating receipt in the pin bores. A pin bearing surface extends within the pin bores and between the pin bores in the lower surface of the floor. The assembly includes a connecting rod with an end fixed to the pin for conjoint oscillation therewith.

Abstract: A piston and an engine are provided that includes various precise configuration parameters, including dimensions, shape and/or relative positioning of combustion chamber features. More particularly, configuration parameters for a piston crown and a piston bowl located within the piston crown are provided. The piston bowl configuration results in a combustion process that yields decreased heat transfer to a cylinder head of the internal combustion engine as well as reduced NOx emissions.

Abstract: A pressure driven apparatus comprising a housing, at least one flexible membrane located within the housing dividing the interior of the housing into at least two chambers. At least one input or exhaust cam assembly operates in conjunction with the at least one flexible membrane to provide an expansion zone within the housing. Fluid enters the housing producing movement of the flexible membrane. The flexible membrane is connected to a drive member such that the movement of the fluid within the expansion zone results in the membrane imparting a force to the drive member. The flexible membrane includes seals used to maintain a dynamic and movable seal with respect to the housing.

Abstract: A piston for an internal combustion engine includes a piston body made of an aluminum alloy material containing silicon and having a piston ring groove formed therein and an anodic oxide film formed on the piston ring groove, wherein a metal containing nickel and zinc is deposited around silicon particles in the anodic oxide film.

Abstract: A piston for an internal combustion engine is provided. The piston includes a piston body which is made of steel. The piston body has a crown portion with an upper combustion surface, a pair of skirts which depend from the crown surface, a pair of pin bosses for receiving a wrist pin and a plurality of pin boss bridges which extend from the pin bosses to the skirts. Each of the pin boss bridges extends axially to a lower end which is opposite of the crown portion and has a rib with an increased thickness at its lower end. At least one of the pin boss bridges has a generally flat counter-bore surface for providing a reference location for machining of the piston body.

Abstract: A piston ring system, having an internal diameter >400 mm, for a piston of a two-stroke internal combustion engine, includes at least a first and a second piston ring each having a convex running surface with a crest of the convexity in contact with a cylinder wall and each being inserted into a respective first and second piston ring groove in the piston, wherein the first piston ring faces a combustion chamber and the second piston ring is disposed axially beneath the first piston ring, and wherein the crest of the convexity of the first piston ring is disposed beneath a radial plane passing through a midpoint of axial height of the first piston ring, and the crest of the second piston ring is disposed above a radial plane passing through a midpoint of axial height of the second piston ring.

Abstract: A piston for an internal combustion engine has a piston head that has a circumferential cooling channel as well as a combustion bowl having a circumferential bowl wall that makes a transition into a piston crown by way of a bowl edge region. The combustion bowl is formed at least in part by a piston base body and the bowl wall is formed at least in part from an insert. The insert is connected with the piston base body by means of beam welding. A lower weld seam is configured in the bowl wall, which seam encloses an acute angle with the piston center axis (M) and ends in the lower half of the cooling channel. An upper weld seam runs from the cooling channel ceiling to the piston crown and is disposed centered or radially offset toward the outside, with reference to the clear width of the cooling channel.

Abstract: A piston for an internal combustion engine includes a piston base material including a pair of skirt portions opposed to each other in a radial direction of the piston base material. The piston includes a multiple-layer coating formed on at least one of surfaces of the pair of skirt portions. The piston further includes marks provided to respective layers of the multiple-layer coating at locations different from each other.

Abstract: The invention relates to a cast piston for an internal combustion engine having a piston base, a cylindrical piston head connected to the piston base, and pin bores provided in an at least partially hollow piston shaft, which is positioned on the side of the piston head opposite the piston base. The piston has one or more supporting ribs located at least partially in the piston shaft, and at least one supporting rib has a recess on the side facing the piston base.

Abstract: The present invention relates to a piston (10, 110, 210) for an internal combustion engine, having a first piston component (11) and a second piston component (12), which jointly form a circumferential cooling channel (23) that is open toward the second piston component (12), whereby the first piston component (11) forms at least a part of a piston crown (13) as well as an outer circumferential wall (34) of the cooling channel, characterized in that the outer circumferential wall (34) of the cooling channel (23) has a circumferential projection (32) below the piston crown (13), which projection is provided with a circumferential guide surface (33) for coolant, directed radially inward.

Abstract: A two-piece piston for an internal combustion engine has an upper piece and a lower piece, the lower piece having an upper base part with an opening lying coaxial to the piston axis into which a pin on the upper piece is inserted. The upper piece is connected to the lower piece with a hexagonal nut screwed onto the pin. A resilient sleeve is arranged between the upper piece and the lower piece comprising an inwardly directed collar on the against which the upper face of the hexagonal nut lies and in the region facing away from the piston crown, a contact surface facing the piston crown lying on a surface on the inner side of the opening. An economically produced two-piece piston results with a resilient sleeve between both screwed piston pieces which exerts a pre-tensioning and thus provides security for the screw connection.

Abstract: A piston is positioned for reciprocal movement in a combustion engine cylinder. Half way between flame plume impingement areas are arranged a first type of protrusions protruding into the combustion chamber and having a smooth form adapted for preserving kinetic energy in a flame plume. Each of the first type of protrusions has a shape of a longitudinal ridge that extends only in the outer bowl area. The first type of protrusions have a left side flank and a right side flank of the ridge when seen from the injector. The left side flank is formed differently compared to the right side flank in order to redirect the movement of a flame plume progressing towards the left side flank in a plane perpendicular to the reciprocal movement, differently compared to corresponding flame plume progressing, towards the right side flank.

Abstract: To provide a piston for an internal combustion engine including a skirt which causes a relatively small frictional resistance and can maintain a favorable frictional property over an extended period of time. In a piston for an internal combustion engine having a skirt 4 on whose sliding surface a resin coating layer is deposited, the skirt 4 comprises a thin walled portion 51 located in a circumferentially middle part thereof and a pair of thick walled portions 52 provided on either lateral side of the thin walled portion 51. The resin coating layer 44 at least in the part thereof deposited on the thick walled portions 52 is formed with a plurality of dimples 45. The skirt may comprise a skirt main body 41 extending axially at a fixed distance from the central axial line of the piston in an axially middle part thereof, and a first reduced diameter portion 42 depending from the lower end of the skirt main body and having a progressively smaller diameter toward a lower end thereof.

Abstract: A piston structure for a four-stroke internal combustion engine is provided, enabling an increase in the intake efficiency and a favorable ignitability to improve the performance of the internal combustion engine. In a piston structure for a four-valve four-stroke internal combustion engine, a piston crown includes: an intake-side inclined flat surface formed in a single plane by bottom surfaces of a pair of intake valve recesses and an intake-side common flat surface; and an exhaust-side inclined flat surface formed in a single plane by bottom surfaces of a pair of exhaust valve recesses and an exhaust-side common flat surface. The intake-side inclined flat surface and the exhaust-side inclined flat surface are formed into a pent-roof shape with a ridge line at an intersection therebetween. The exhaust-side inclined flat surface extends into the intake valve recesses, and the ridge line is located on a side of the intake valve recesses.

Abstract: A method for producing a piston for an internal combustion engine, composed of first and second piston components, has the following steps: (a) providing a blank of the first piston component composed of a tempered or precipitation-hardened steel, having at least one joining surface, (b) providing a blank of the second piston component composed of a tempered or precipitation-hardened steel, having at least one joining surface, (c) tempering or precipitation-hardening the blanks, (d) friction-welding the joining surfaces of the blanks to produce a piston blank, with the formation of at least one friction-welding seam and a heat influence zone in the region of the at least one friction-welding seam, (e) annealing or low-stress annealing of the piston blank, thereby obtaining the heat influence zone(s), (f) re-machining and/or finishing the piston blank to produce a piston. A piston so produced is also provided.

Abstract: A piston for an internal combustion engine and method of construction thereof are provided. The piston includes a piston body having an upper combustion surface and an annular cooling gallery surrounding an undercrown region. An outer wall depends from the upper combustion surface. An annular ring belt region is formed in the outer wall adjacent the upper combustion surface. The ring belt region has at least one ring groove formed therein. At least one oil passage extends from the at least one ring groove to the cooling gallery. The oil passage has a first portion depending radially inwardly from the ring groove and a second portion ascending radially inwardly from the first portion to the cooling gallery.

Abstract: A piston for an internal combustion engine has an upper piston part and a lower piston part, which form an outer circumferential cooling channel. The piston has pin boss connections that lie opposite one another, at which pin bosses are provided, which have pin bores that define a center axis (M). The upper piston part and the lower piston part are connected with one another by way of outer joining surfaces and inner joining surfaces. A bridge that runs essentially parallel to the center axis (M) is configured in the lower piston part, in the region of the pin boss connections. The bridge has two longitudinal sides that delimit an upper bridge surface.

Abstract: A method for the production of a piston has the following method steps: (a) providing a blank of a piston base body, having an outer joining surface, an inner joining surface and a circumferential lower cooling channel part that runs between the two joining surfaces, (b) providing a blank of a piston ring element, having an outer joining surface, an inner joining surface and a circumferential upper cooling channel part that runs between the two joining surfaces, (c) forming a circumferential widened region on at least one joining surface, the widened region extending toward the related cooling channel part, (d) connecting the blank of the piston base body with the blank of the piston ring element by way of their joining surfaces, by friction welding, to produce a piston blank, and (e) machining the piston blank further and/or finish-machining it to produce a piston.

Abstract: A sliding member for which adhesiveness between the surface of a base member and metal coating is enhanced. An undercoat layer having a resin material at the surface thereof is provided, and a solid lubricating portion is formed on the undercoat layer so as to provide a sliding face from at least one kind of material of silver, silver alloy, copper and copper alloy. An intermixture layer in which both the undercoat layer and the solid lubricating portion are intermixed with each other is interposed between the undercoat layer and the solid lubricating portion.

Abstract: An internal combustion engine has a cylinder (2) wherein a combustion chamber (3) is formed which is delimited by a piston (5) journalled to move back and forth. At least one transfer channel (14) is provided which connects the crankcase (4) of the engine to the combustion chamber (3) in at least one position of the piston (5). The engine has a supply channel (13) which opens with a supply channel inlet (11) at the cylinder bore (34). The supply channel (13) is connected to the transfer channel (14) via at least one piston pocket (22, 42) in at least one position of the piston (5). In order to achieve low exhaust-gas values of the engine, the piston pocket (22, 42) has a distance (a) to a lower edge (27) of the transfer window (15) which is less than the distance (b) to a lower edge (26) of the inlet (11) of the supply channel at bottom dead center of the piston (5).

Abstract: Piston for use in internal combustion engines, having a piston skirt composed of skirt walls and box walls, said walls enclosing a recess wherein the at least one skirt wall is provided for use on the pressure side of the piston in the installed state. Said piston is in particular characterized in that, in at least one partial region of at least one skirt wall provided for use on the pressure side of the piston, the recess is in substantially the shape of a parabola, a section of an ellipse or a catenoid, wherein said parabola, said section of an ellipse or said catenoid lies in a plane substantially parallel to the piston crown.

Abstract: An engine includes a cylinder block having a bore, a piston fitted into the bore so as to form a combustion chamber and to be able to reciprocate, a cylinder head for closing the combustion chamber and having valve bores communicating with the combustion chamber, and valves for opening and closing the valve bores. A heat insulating coating is applied on a wall face of at least one of the piston, the cylinder head, and the valves and facing the combustion chamber. The heat insulating coating includes resin and a plurality of hollow nanoparticles embedded in the resin, smaller in diameter than a thickness of the heat insulating coating, and smaller than or equal to 500 nanometers in size.

Abstract: A single-piece piston body for an internal combustion engine includes a crown portion having a circumferential ring belt including an oil ring groove configured to accommodate an oil control ring and a skirt portion having a first skirt wall disposed on the major thrust side and a second skirt wall disposed on the minor thrust side of the piston, and two box walls that connect the skirt walls and which are set back with respect to the ring belt. A first plurality and a second plurality of axial drain passages extend from the oil ring groove to the bottom of the crown portion, the first and second pluralities of axial drain passages being substantially centered at opposite box sides of the piston and each plurality of axial drain passages spanning an arcuate portion of about 45-75 degrees.

Abstract: The present invention reduces weight while assuring required rigidity of a piston reduces cost of the piston. A piston includes first and second pin bosses supporting a piston pins, a first side wall coupling the first pin boss and a piston skirt, a second side wall coupling the second pin boss and the piston skirt, and a pair of bridges coupling the first and second side walls and forming upward spaces just above. First and second through holes are formed in the first and second side walls. The first and second through holes and the upper spaces are formed by a single punching process using a punch and, simultaneously, the bridges are formed.

Abstract: In an internal combustion engine, a variable compression ratio mechanism able to change a mechanical compression ratio and a variable valve timing mechanism able to change a closing timing of an intake valve are provided. When a load is higher than a predetermined load, an amount of intake air inside a combustion chamber is controlled by controlling the closing timing of the intake valve, while when the engine load is lower than the predetermined load, the amount of intake air inside the combustion chamber is controlled by controlling both the closing timing of the intake valve and the opening degree of the throttle valve.

Abstract: The present invention relates to a piston (10) for an internal combustion engine, comprising a piston head (11) and a piston skirt (16), wherein the piston head (11) has a circumferential ring part (15) and a circumferential cooling channel (23) in the region of the ring part (15), wherein the piston skirt (16) has piston bosses (17), which are provided with boss bores (18) and which are arranged on the underside (11a) of the piston head (11) by means of boss connections (19), wherein the piston bosses (17) are connected to each other by means of running surfaces (21, 22). According to the invention, at least one axial bore (24a, 24b, 24c, 24d), which is closed to the outside and which is arranged between a running surface (21, 22) and a boss bore (18), is provided inside a piston boss (17), the at least one bore (24a, 24b, 24c, 24d) opens into the cooling channel (23), and the cooling channel (23) and the at least one bore (24a, 24b, 24c, 24d) contain a filling (27) of sodium and/or potassium.

Abstract: The present invention relates to a piston (10, 110, 210) for an internal combustion engine, comprising a piston crown (13), a circumferential ring part (16), a circumferential cooling channel (27) arranged in the vicinity of the ring part (16), boss supports (21) connected below the piston crown (13), piston bosses (18) connected thereto, and a piston skirt (17). According to the invention, a cavity (28) closed on all sides and having a closure element (29, 129, 229) arranged in the direction of the piston skirt (17) is provided below the piston crown (13).

Abstract: The oil control ring (1) comprises a retaining ring (2) and a scraper (3) having a scraper fin (3a), wherein the scraper (3) is arranged in the retaining ring (2) in such a way that the scraper fin (3a) is oriented towards the center (1a) of the oil control ring (1) in order to scrape oil on a piston rod (6). The scraper (3) comprises a plurality of scraper segments (3e) which are arranged in succession in the circumferential direction (1b) of the oil control ring (1), and the retaining ring (2) has a groove (2b) for accommodating the scraper segments (3a) in a positive manner, and the retaining ring (2) has an abutment point (2g). The retaining ring (2) forms at least one plastic first end face (2d, 2e) which is oriented towards the center (1a) of the oil control ring (1).

Abstract: In a piston (1) for combustion engines are included a piston crown (2), a piston skirt (3) and portions (4A, 4B; 13) for receiving a piston pin (5) by means of which the piston is pivotally supported on a connection rod, whereby a protection (7) covering a major portion of a bottom side of the piston crown is supported on the piston pin. The protection is fitted in sealing engagement with a first inner portion of the piston skirt, forming an uninterrupted gap in relation to a main portion of the piston crown and with at least a portion of the protection being provided at a distance inside a second outer portion of the piston skirt.

Abstract: A bearing bushing for a connecting rod and a combination of a connecting rod and a bearing bushing are provided. The connecting rod has a small end which includes a bearing bore. A first region of the bearing bore, which in operation is subjected to compressive loading, is longer than a second region of the bearing bore which is subjected to tensile loading. In order to modify a bearing bushing and a connecting rod so that with simple production and optimized weight the connecting rod has good bearing properties for the piston pin, the bearing bushing already has, before insertion thereof into the bearing bore, a shape adapted to the end edge contour of the bearing bore, wherein the first region of the bearing bushing is likewise longer than the second region thereof. A method of producing such a small end is also disclosed.

Abstract: A two-piece piston is formed by friction welding an upper member to a lower member, wherein the upper and lower members are precision cast to net final dimensions such that no post-casting machining is required prior to the friction-welding process. The upper member includes a substantially flat crown and combustion surface extending radially inward from the crown. The lower member includes a pair of opposing skirts, each having a bore formed therethrough for receiving a connecting rod pin. The upper member and lower member each include at least two corresponding connecting surfaces that form a welded joint therebetween when the upper and lower members are friction welded together. The finished piston includes an integral cooling oil reservoir adjacent to the combustion surface.