Abstract: An internal combustion engine including at least one cylinder with a piston moveable therein in an engine block in which microwaves are introduced into a combustion chamber through a microwave window, wherein the combustion chamber is formed by a piston base and a cylinder head, characterized in that the combustion chamber includes a combustion chamber wall which functions as a microwave window at least in portions wherein the combustion chamber wall is made from a wall layer that is made from a ceramic material in which wall layer at least one annular circumferential hollow conductor cavity is arranged with at least one inlet opening for the microwave and which includes at least one outlet opening for the microwave that is run in the annular hollow conductor cavity of the wall layer. In general the invention provides safe ignition of lean fuel air mixtures.

Abstract: A machine may comprise a piston; a memory; and an electronic control module. The electronic control module may be configured to determine a temperature of a bowl rim of the piston; calculate a temperature of an oil gallery of the piston based on the temperature of the bowl rim; determine a carbon deposit growth rate of the piston based on the temperature of the oil gallery; determine an amount of time between a current time and the time when the previous carbon deposit growth was calculated; calculate a current carbon deposit growth on the piston; and take a remedial action based on the current carbon deposit growth. The current carbon deposit growth may be calculated based on: a previous carbon deposit growth on the piston, an amount of time between a current time and a time when the previous carbon deposit growth was calculated, and the carbon deposit growth rate.

Abstract: An internal combustion engine includes a combustion chamber, a fuel injector injecting fuel into the combustion chamber, a cylinder, a piston having a crown and reciprocating in the cylinder, the crown being exposed to the combustion chamber, and an ignition delay enhancer prolonging an ignition delay of a fuel-air mixture in the combustion chamber. A ceramic member is disposed on at least a fuel injection port, to which fuel is injected from the fuel injector, of the crown of the piston.

Abstract: A piston (10) for an internal combustion engine has discrete, cylindrical support surfaces (18, 24) for supporting a piston pin, wherein, between at least two support surfaces (18, 24), there is provided a recess (26) which has a radial depth of at least 10% of half of the distance between two opposite support surfaces.

Abstract: An assembly includes a cylinder having a bore diameter, and a piston disposed within the cylinder. The piston is provided with a top land and a top ring groove. The top land and the cylinder are provided with a tight top land clearance. The ratio of the top land height to the bore diameter is less than or equal to 0.075.

Abstract: An engine piston structure includes: a piston (1); a connecting rod (10) having a small end part (10a) coupled to the piston (1), and having a large end part (10b) coupled to a crankshaft; a piston pin (2) through which the piston (1) and the small end part (10a) of the connecting rod (10) are coupled together and which has a hollow cross section; and at least one dynamic vibration absorber (20) provided inside the piston pin (2) to reduce resonance of the piston (1), the piston pin (2), and the small end part (10a) of the connecting rod (10) in combination with respect to the large end part (10b) of the connecting rod (10) during a combustion stroke.

Abstract: A two-stroke engine includes a crankcase defining a cylinder bore, a piston moveably disposed within the cylinder bore, and a cylinder head that covers the cylinder bore. A wall surface of the cylinder bore, a piston combustion surface of the piston, and a head combustion surface of the cylinder head, cooperate to define a combustion chamber for combusting a fuel therein. A thermal conductivity reducing mechanism is disposed in thermal connectivity with at least one of the crankcase, the piston, and the cylinder head for reducing heat transfer from combusted fuel within the combustion chamber to at least one of the crankcase, the piston, and the cylinder head. The thermal conductivity reducing mechanism may include a layer of low conductivity material coating one of the surfaces defining the combustion chamber, or a void in the cylinder head and/or the crankcase adjacent the combustion chamber.

Abstract: A diesel engine includes a cylinder block having a cylinder cavity defined therein. A cylinder head is coupled to the cylinder block and includes a lower semi-hemispherical surface defined thereon that defines an upper boundary of a combustion chamber. The engine includes a piston slideably disposed within the cylinder cavity that includes a piston crown having an upper surface configured to define a first portion of a lower boundary of the combustion chamber. The upper surface of the piston crown includes an axi-symmetric semi-hemispherical shape configured to correspond to the lower semi-hemispherical surface of the cylinder head.

Abstract: A piston including an abradable coating applied to a round surface of the piston is provided. The shape of the round surface is not greater than 0.1 mm from a circular shape, and thus is relatively inexpensive to machine. As the piston reciprocates in an internal combustion engine, the abradable coating rubs against another component, such as a cylinder liner or wrist pin, to achieve suitable contact geometry, such as an oval, asymmetric, or other non-round shape. Thus, a costly machining process is not required to achieve the desired contact geometry. The abradable coating can also be applied to ring lands, skirt sections, or along pin bores of the piston. The abradable coating can also be applied to a wrist pin or an opening of a connecting rod which receives the wrist pin. The abradable coating can be formed from a polymer-based material or an aluminum-silicon alloy-based material.

Abstract: A pre-finished piston part is disclosed that may be used to form a piston assembly. A pre-finished piston may include a lower part defining a piston axis, the lower part having a skirt and forming a lower surface of a cooling gallery. The lower part may include a radially inner bowl surface defining a lower part radially inner mating surface. The pre-finished piston assembly may further include an upper part having a radially outer bowl surface meeting the radially inner bowl surface at a radially inner joint. The upper part may include a radially inner wall defining a radially inner upper part mating surface. The radially inner wall may define a radially inwardly facing surface that defines a non-parallel angle with the radially inner bowl surface where the radially inner bowl surface meets the radially innermost edge of the radially inner mating surface.

Abstract: A piston for an internal combustion engine may include a piston head and a piston skirt. The piston head may include a piston crown, an encircling fire land, an encircling ring belt having a plurality of ring grooves and an encircling cooling duct disposed radially inwards from the ring belt. The cooling duct may be open in an axial direction away from the fire land and may be at least partially closed via a closure element. The cooling duct may have a cooling duct base and a cooling duct ceiling. The closure element may be arranged on the piston head to define the cooling duct base in a position above a lowermost ring groove of the plurality of ring grooves.

Abstract: An internal combustion engine includes a combustion chamber having a piston, the piston having at least one arcuate indent of a first type formed in the top surface, and at least one arcuate indent of a second type, wherein the first type includes a first recirculation surface having a concave shape at a first radius and extending along a spiral direction adjacent the entry surface, and wherein the second type includes a second recirculation surface having a concave shape at a second radius that is smaller than the first radius. During operation, a fuel jet provided into the first type occupies a radially outward portion of the combustion chamber, and a fuel jet provided into the second type occupies a central portion of the combustion chamber.

Abstract: Exemplary piston assemblies and methods of making the same are disclosed. An exemplary piston assembly may include a piston crown and a piston skirt that is received in a central opening of the crown. The piston crown may include a ring belt portion defining, at least in part, a cooling gallery. The crown and skirt may each further include corresponding mating surfaces that extend about a periphery of the crown and skirt. The skirt mating surface and crown mating surface may generally be secured to each other that the crown and the skirt cooperate to form a continuous upper combustion bowl surface. The skirt and crown may cooperate to define a radially outer gap about a periphery of the piston crown.

Abstract: A power cylinder system for a reciprocating engine includes a steel piston configured to move within a cylinder of the reciprocating engine. The system also includes a groove extending circumferentially about the piston beneath a top land of the piston and configured to support a ring having an inner circumferential face. One or more channels are formed in the top land and are configured to facilitate transfer of combustion gases to a space between a portion of the groove and the inner circumferential face of the ring.

Abstract: The invention relates to a die casting ring (1) internally fitted with radial teeth (11) to be engaged into matching seats (22) provided on a piston (2). This piston-ring assembly prevents mutual rotation or axial translation, in addition to ensuring an optimal seal against infiltration of liquid metal during the die casting process. When the ring has a cutout (10), it can be mounted accurately onto the piston because the teeth (11) allow the cutout to be positioned anywhere relative to the piston.

Abstract: The invention relates to temperature sensors, in particular high-temperature sensors, having an optionally coated substrate, at least one resistor structure, and at least two connection contacts. The connection contacts electrically contact the resistor structure, and the substrate is made of zirconium oxide or a zirconium oxide ceramic stabilized with oxides of a trivalent metal and a pentavalent metal. The substrate is coated with an insulation layer and the resistor structure and the free regions of the insulation layer, on which no resistor structure is disposed, are at least partially coated with a ceramic intermediate layer. A protective layer and/or a cover is disposed on the ceramic intermediate layer. At least one electrode may be disposed, at least at one connection contact, alongside the resistor structure on the substrate. The invention also relates an exhaust-gas system for controlling and/or regulating an engine, particularly a motor vehicle engine, containing these temperature sensors.

Abstract: An internal combustion engine includes a first low-pressure cylinder housing a first low-pressure piston, and a first high-pressure cylinder housing a first high-pressure piston, the first high-pressure cylinder being arranged in upstream fluid communication with the first low-pressure cylinder for providing exhaust gas into the first low-pressure cylinder.

Abstract: A piston for an internal combustion engine is proposed with a piston head and with two pin bosses which lie opposite one another, are molded integrally onto the piston head in the direction which faces away from the piston head, and have in each case one pin bore. In each case one turned groove is formed into the radially inner regions of the lower halves of the pin bores, which halves face away from the piston head.

Abstract: A piston for an internal combustion engine may include a piston head and a piston skirt. The piston head may include a piston crown, a circumferential fire land, a circumferential ring belt having a plurality of ring grooves, and a circumferential cooling duct. The cooling duct may be open in a direction away from the fire land and may be at least partially closed by a closure element. The cooling duct may include a cooling duct bottom and a cooling duct ceiling. The piston skirt may have at least two piston bosses connected to one another via at least two running faces. At least one running face may have an inner face connected via a connecting land to an underside of the piston head.

Abstract: A piston of an internal combustion engine includes a crown portion; a pair of thrust-side and counter-thrust-side skirt portions; and a pair of apron portions connecting the thrust-side skirt portion with the counter-thrust-side skirt portion. Each of the pair of apron portions includes an upper end wall connected with the crown portion, and a pin boss portion supporting a piston pin. A reverse-surface-side portion of the crown portion is formed with a hollow portion extending along an outer surface of the upper end wall of the apron portion. The upper end wall of the apron portion includes a bending portion between an outside surface of the pin boss portion and a circumferential end of the skirt portion. The bending portion bends in a step-like manner from the outside surface of the pin boss portion toward the circumferential end of the skirt portion.

Abstract: Provided is a piston push rod assembly which can prevent discomfort from being imparted during the operation of a brake pedal by a driver. A piston push rod assembly, wherein: a second piston is provided with a piston slide section which is housed in a cylinder and which slides relative to the cylinder, and a connection tube section which is connected to a push rod; the piston slide section is covered by metal plating; the connection tube section has a non-plated section; and the second piston and the push rod are connected by the caulking of the connection tube section when the push rod has been inserted inside the connection tube section.

Abstract: The present disclosure provides for a vehicle engine having an EGR system where pairs of cylinders are directly connected to each other. For example, a first and second cylinder may be operably connected by a valve actuator where a high energy, blowdown exhaust gas from the first cylinder may flow through a first flow path directly from the first cylinder to the second cylinder. Likewise, during the firing stroke of the second cylinder, a high-energy, blowdown exhaust gas may flow from the second cylinder through a second flow path directly into the first cylinder. This arrangement may pair cylinders to take advantage of high-energy exhaust gas.

Abstract: An engine may include a cylinder having a first combustion chamber at one end thereof and a second combustion chamber at an opposing end thereof, first and second cylinder heads at an end of the first combustion chamber and the second combustion chamber, respectively, and a double-faced piston slidably mounted within the cylinder. The piston may be configured to move in a first stroke from the first end to the second end of the cylinder. The piston and the cylinder may be configured such that the first stroke includes an expansion stroke portion during which chemical energy from combustion in the first combustion chamber is converted into mechanical power of the piston, and a momentum stroke portion during which the piston continues to move to the second end of the cylinder and gases are exchanged between the first combustion chamber and a location outside the cylinder.

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: An assembly for a combustion engine may include a piston and a connecting rod. The piston may include a piston crown, a piston skirt, and respective portions for accommodating a piston pin through which the piston is intended to be supported on the connecting rod. The piston skirt may have a completely closed bottom part and apertures may be provided in the portion for accommodating the piston pin. The apertures may seal against the piston pin to enclose a bottom part of the piston crown as well as the piston crown portion for accommodating the piston pin. The connecting rod may have a fork shape in an end facing the piston.

Abstract: A method for producing a piston for an internal combustion engine, which piston has at least one cooling channel and is produced from at least one upper part and one lower part. The cooling channel of the piston is formed of the upper part and the lower part where the upper part and the lower part of the piston are each produced by means of a forging process At least one rib-like element, in particular, at least one rib, is additionally forged during the forging of the upper part in an area of the cooling channel and/or at least one rib-like element, in particular, at least one rib, is additionally forged during the forging of the lower part in an area of the cooling channel. Two alternative production methods and to a piston for an internal combustion engine are disclosed.

Abstract: Pistons and methods of making the same are disclosed. An exemplary piston assembly may include a piston crown and skirt. The crown may include a crown collar wall extending downward toward a free end of the crown collar wall. The skirt may include a pair of oppositely disposed pin bosses that each define piston pin bores configured to receive a piston pin for securing a connecting rod between the pin bosses. The skirt may further include a radially inner skirt mating surface abutted along a radially inner interface region with the radially inner crown mating surface, and a radially outer skirt mating surface abutted along a radially outer interface region with the radially outer crown mating surface such that a cooling gallery is substantially enclosed. The skirt may further include an inner collar wall extending upwards to the free end of the crown collar wall.

Abstract: A steel piston with an oil gallery, and process for forming a steel piston oil gallery channel, which corresponds to the complex shape of the combustion bowl in the piston crown. The piston crown is made by a cast metal or powder metal forming process. The oil gallery channel is formed to the basic shape that corresponds to the shape of the walls of the combustion bowl. Machine-turning surfaces in the oil gallery channel can be machine-finished as desired. Surfaces in the oil gallery which cannot be machined with conventional turning operations, such as recesses and protrusions into the channel, are left in the original as-formed condition.

Abstract: Exemplary piston assemblies and methods of making the same are disclosed. An exemplary piston may include a piston body defining a piston axis, the piston body having a skirt and forming a lower surface of a cooling gallery. The body may include radially inner and outer body mating surfaces. The piston may further include a cooling gallery ring cooperating with the piston body to form the cooling gallery. The piston body and cooling gallery ring may be joined together along radially inner and radially outer interface regions to form a generally one-piece piston assembly. In some exemplary approaches, mating surfaces of the body and ring may be positioned adjacent a support surface configured to inhibit or prevent weld spatter formed in a process joining the ring and body from the cooling gallery.

Abstract: Methods and systems are provided for supplying cooling oil to a piston of an engine cylinder. In one example, a method may include repeatedly activating an oil supply only during a part of a cylinder cycle synchronous with a reciprocating motion of the piston. In particular, supply of cooling oil may be initiated by displacing a poppet valve arranged within a piston cooling assembly via a reciprocating motion of the piston.

Abstract: A cylinder liner and piston configuration for an internal combustion engine includes features for improving the cooling of the piston. Specific ratios and dimensions are included to optimize the features of the cylinder liner and piston. Also included are unique piston features that assist in achieving some of the specified dimensions and ratios.

Abstract: A piston of an internal combustion engine, includes a piston upper part and a piston lower part which are supported via corresponding joining webs, in each case forming a joining zone connected in a material-to-material manner by means of a multi-orbital rotary friction weld. The joining webs and which are in each case directly connected have a wall thickness S1, S2 which is identical as far as possible. The piston encloses a combustion-chamber recess and at least one cooling duct which are made centrally or eccentrically in the piston. The combustion chamber recess and the cooling duct form a circular contour or a contour which deviates from a circular shape.

Abstract: A cooling duct piston (1) for combustion engines. The cooling duct piston has a piston basic body (2) that is connected to a lining part (3), which is facing an assigned combustion chamber. Here, the lining part (3) completely forms the piston surface (4) of the cooling duct piston (1) that faces the combustion chamber. An encircling depression (5) is provided in the surface of the piston basic body (2) facing the combustion chamber. The lining part (3) provides a permanent connection at least with the surface of the piston basic body (2) facing the combustion chamber, and thus bridges the encircling depression (5), such that the encircling depression (5), with the lining part (3) that bridges it, forms a cooling duct (6).

Abstract: A system includes a reciprocating engine having a cylinder liner and a piston disposed within the cylinder liner. The cylinder liner includes an inner wall and extends around a cavity. The inner wall includes a first axial end, a second axial end, a piston travel portion, and a top portion. The top portion is nearer to the first axial end of the cylinder liner than to the second axial end of the cylinder liner. The top portion has a first surface finish with a first roughness average (Ra1) greater than approximately 2 ?m and a total waviness (Wt) less than approximately 0.1 mm. The piston is configured to move in a reciprocating manner within the cylinder liner. The piston includes a top land configured to be radially opposite the top portion of the inner wall of the cylinder liner when the piston is at a top dead center position.

Abstract: The piston is provided with a pair of radial holes opened to an external circumferential recess and lodging and retaining one respective end of a pin, to which is coupled a driving mechanism to reciprocate the piston inside a cylinder. The radial holes are completely sealed in order that the axial extension of a bottom radial gap provided by a bottom bearing surface of the piston work together with the axial extension of a top radial gap provided by a top bearing surface to provide the required leakage restriction of the refrigerant gas and also the required bearing of the piston inside the cylinder. The axial extension of each of the top bearing surface and of the bottom bearing surface is insufficient to provide by itself said required leakage restriction of the refrigerant gas.

Abstract: A method for the production of a piston for an internal combustion engine, having a piston head, a piston skirt, and a circumferential recess configured between the piston head and the piston skirt. The piston has a piston base body and a piston ring element. The piston base body has at least a crown region of a combustion bowl as well as the piston skirt. The piston ring element has at least a piston crown, a wall region of the combustion bowl, a circumferential top land, and a circumferential ring belt with ring grooves. The piston ring element has a circumferential cooling channel between the wall region of the combustion bowl and the ring belt, closed with a closure element. The piston base body and the piston ring element are connected by a circumferential joining seam in the region of the combustion bowl.

Abstract: The invention relates to a piston ring (10, 110, 210, 310, 410, 510, 610) for pistons of internal combustion engines, having a ring running surface (14), a ring back (11), an upper ring flank (12), a lower ring flank (13), and two ring joint ends spaced apart by a gap (15). According to the invention, at least one opening (17, 121, 217, 223, 325, 407) is provided in the ring running surface (14), which opening forms a fluid connection between the ring running surface (14) and the ring back (11) or a ring flank (12, 13).

Abstract: A combustion control device for an engine capable of operation over a wide range and in which the NOx discharged amount is small is provided, as well as a combustion method for a homogeneous lean air/fuel mixture. The combustion method for a homogeneous lean air/fuel mixture of the present invention forms a homogeneous lean air/fuel mixture inside of the cylinder of the engine, and then causes this homogeneous lean air/fuel mixture to combust by way of spark ignition. A temperature at which a steep rise in a laminar burning velocity occurs when changing a cylinder temperature under a pressure condition corresponding to compression top dead center is defined as an inflection-point temperature. With the combustion method of the present invention, the cylinder temperature at compression top dead center inside of the cylinder is raised to higher than the inflection-point temperature upon combusting the homogeneous lean air/fuel mixture.

Abstract: The axial line of an intake valve is inclined, and a gap between a piston crown surface and a valve head of the intake valve expands in accordance with the approach of the crankshaft axis. A relationship of G2>G1 is fulfilled, where G1 stands for a minimum gap between the lower surface of the cylinder head that is positioned between the intake valve and the exhaust valve facing the intake valve, with the crankshaft axis being interposed therebetween, and the piston crown surface in a top dead center, and G2 stands for a gap at a position that is the closest to the crankshaft axis, from among the gaps between the lower surface of the valve head of the intake valve and the piston crown surface at a center timing of a valve overlap period in which the intake valve and the exhaust valve are both open.

Abstract: A piston for an internal combustion engine has shaft elements which have inner surfaces that correspond to those regions of the shaft elements in which the shaft elements are thinner than 7% of the piston diameter “D”, and have outer surfaces that define in a radially outward direction those regions of the shaft elements which, viewed in the circumferential direction, lie outside angle ranges of more than 40° on both sides of the pin bore axis. The ratio of the content of the inner surface to the ratio of the content of the outer surface is more than 60%. The shaft elements hereby become elastically compliant, which upon a temperature-induced radial expansion of the piston shaft reduces the pressure that the shaft elements exert on the cylindrical inner wall, whereby the friction losses of the piston, and hence the CO2 emission of the engine fitted are reduced.

Abstract: A method for producing piston for an internal combustion engine which 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: An internal combustion engine piston includes a crown including a ring belt portion including an outer wall and ring grooves, wherein the outer wall has a first end, a combustion bowl including an inner wall having a second end, a top wall extending between the inner and outer walls, and an annular cavity between the inner and outer walls, including an opening opposite the top wall, and at least partially defining a cooling gallery. At least one insert protrudes into the cooling gallery so as to axially overlap the ring grooves to direct coolant to desired portions of the crown.

Abstract: A cylinder liner and piston configuration for an internal combustion engine includes features for improving the cooling of the piston. Specific ratios and dimensions are included to optimize the features of the cylinder liner and piston. Also included are unique piston features that assist in achieving some of the specified dimensions and ratios.

Abstract: A piston and method of construction are provided. The piston includes a piston body having an upper combustion surface configured for direct exposure to combustion gases within a cylinder bore with an undercrown surface located beneath the upper combustion surface. The piston body also includes a ring belt region configured for receipt of at least one piston ring adjacent the upper combustion surface with a cooling gallery configured radially inwardly and in substantial radial alignment with the ring belt region. The piston further includes a non-stick coating material bonded to at least one of the undercrown surface and at least a portion of the cooling gallery, wherein the non-stick coating material inhibits the build-up of carbon deposits thereon.

Abstract: A piston for an internal combustion engine, having a piston base body, a piston ring element having at least an inner region of a piston crown, and a piston skirt. The piston is provided with pin bosses having pin bores and the ring element has at least an outer region of a piston crown having a circumferential top land and a circumferential ring belt provided with ring grooves. The piston base body and piston ring element are joined together by way of corresponding, conical joining surfaces configured on them.

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: A method of establishing and maintaining a piston compression height during portions of a combustion cycle in a differential-stroke cycle combustion engine, includes providing a piston seat cup coupled to said first piston part and a piston seat cover operatively associated with said piston seat cup and defining a sealed piston seat cavity, abutting said second piston part with said piston seat cover and moving said piston seat cover relative to said piston seat cup, aligning a fluid ingress aperture with a cooperating piston rod passage and piston pin inlet for a portion of said combustion cycle thereby allowing fluid to enter said piston seat cavity, and aligning a fluid egress aperture with a cooperating piston pin passage and piston rod outlet for a portion of said combustion cycle thereby allowing fluid to exit said piston seat cavity.

Abstract: A piston for an internal combustion engine and method of construction thereof is provided. The piston includes a piston body having an upper combustion surface with a combustion bowl depending from the upper combustion surface. The piston body has a ring belt region configured for receipt of at least one piston ring adjacent the upper combustion surface. A cooling gallery is configured in radial alignment with the ring belt region. An annular combustion bowl rim region extends between the upper combustion surface and the combustion bowl, and a bonded seam extends from the combustion bowl rim region radially outwardly to the cooling gallery. The bonded seam has material properties exhibiting an enhanced ability to withstand the extreme temperature, pressure, stress and highly corrosive and erosive effects of the combustion gases relative to the surrounding material of the piston body.

Abstract: A heat-shielding film formed on the wall surface of a metal base material contains a plurality of ceramic hollow particles (1) and metal phases (2) to which the plurality of ceramic hollow particles (1) are joined at points. Each of the plurality of ceramic particles (1) is joined at a point, through the metal phase (2), to another ceramic particle among the plurality of ceramic particles (1) so that the plurality of ceramic particles (1) are joined to each other. The plurality of ceramic hollow particles (1) of the heat-shielding film (10) and the wall surface are joined at points to the metal phases (2) so that the plurality of ceramic hollow particles (1) are joined to the wall surface.

Abstract: A piston with a piston body extending along a longitudinal central axis and having a crown portion and a pair of pin bosses is provided. The crown portion includes a combustion wall with a combustion bowl formed therein and a pair of ribs depending from the combustion wall. One of the ribs depends from the combustion wall directly below the combustion bowl, and the other rib is radially spaced from the combustion bowl. As such, one of the ribs depends lower along the longitudinal central axis than the other of the ribs. The ribs provide support to the crown portion and also act as a heat sink to extract heat from the combustion wall.