Abstract: A lubricating configuration in a two-stroke cycle, opposed-piston engine for a piston wristpin minimizes losses in oil pressure at the wristpin as the piston approaches bottom center and reduces the required oil supply pressure to the engine. The wristpin is constructed to absorb and store oil pressure energy when oil pressure at the wristpin is high, and to release that stored energy to pressurize the oil at the wristpin when connecting rod oil pressure is low.

Abstract: A piston pin for connecting a small connecting rod eye of a connecting rod with a piston of an internal combustion engine may include an inner bore with an eccentricity relative to an outer surface of the piston pin. The eccentricity may amount to a maximum of 0.5 mm. The outer surface may include spiral-shaped lubricating grooves.

Abstract: A piston for an internal combustion engine includes a piston body having an outer cylindrical surface defining a longitudinal piston axis, a combustion face defining a compound combustion bowl, and a compound rim extending radially outward from the compound combustion bowl to the outer cylindrical surface. The compound combustion bowl includes a convex inner bowl surface defining a conical projection and a concave outer bowl surface. The compound rim includes a flat outer rim surface adjoining the outer cylindrical surface, and a convex inner rim surface adjoining the compound combustion bowl. The convex inner bowl surface transitions smoothly to the concave outer bowl surface, and the convex inner rim surface transitions abruptly to the concave outer bowl surface at an edge of the compound combustion bowl.

Abstract: A sliding component for an internal combustion engine includes: a sliding component main body that includes a plurality of concave portions formed in a predetermined portion thereof; and a coating layer that covers a portion of the sliding component main body, in which the plurality of concave portions are not formed.

Abstract: The invention relates to a piston for an internal combustion engine, comprising a piston head and a piston skirt, the piston head having a peripheral annular part and in the region of the annular part, a peripheral cooling channel. The piston skirt comprises piston bores provided with hub bores, which are arranged over the hub connections on the underside of the piston head. The piston hubs are interconnected over the running surfaces. According to the invention, the wall of the cooling channel which extends in the region of the annular part comprises an inclined portion and together with the central axis of the piston (M), forms an acute angle (a). At least one bore which is closed towards the outside is arranged between a running surface and a hub bore such that the at least one bore leads into the cooling channel, and that the cooling channel and the at least one bore contain a coolant in the form of a metal or a metal alloy which have a low-melting point.

Abstract: A piston arrangement comprising: a piston, a first chamber, a second chamber and a power transfer assembly; wherein the piston comprises a first head movable within the first chamber and a second head movable within the second chamber; wherein, in operation, the piston follows a linear path in reciprocating motion along a first axis; wherein the power transfer assembly comprises a shaft rotatably coupled to a shuttle bearing and arranged to convert the reciprocating motion of the piston to rotary motion of the shaft; wherein the shuttle bearing moves relative to the piston in reciprocating motion along a second axis substantially transverse to the first axis; and wherein the shuttle bearing is coupled to the piston via a non-planar bearing surface thereby allowing rotation of the shuttle bearing.

Abstract: A piston for an internal combustion engine is located within a cylinder of the engine. The piston includes a dish-shaped depression in a surface of the piston exposed to a combustion chamber of the cylinder providing a recess from a nominal top of the piston. The depression includes a depression boundary located at the nominal top of the piston and proximate to an outer diameter of the piston, an apex, and inclined walls connecting the apex to the depression boundary.

Abstract: A piston for an internal combustion engine is disclosed. The piston may have a piston skirt with a centre axis. The piston may also have a piston crown disposed adjacent a top of the piston skirt. The piston crown may have a diameter D. The piston crown may have a piston crown margin of width b extending in a circumferential direction. The piston crown may also have a piston trough with a depth t. The piston trough may have a piston trough wall with a base diameter. The piston trough may also have at least one recess with a height h. The height h parallel to the direction of the centre axis may satisfy the following requirement: 0.2 t<=h<=t.

Abstract: An engine block of an internal combustion engine is disclosed. The engine block may have a piston and at least one gas exchange valve. The piston may have a piston skirt having a first center axis. The piston may also have a piston head delimiting the piston skirt at the top with a diameter D. The piston head may have a piston head edge and a piston head recess with a piston recess wall having a height H. At least one valve pocket may be formed into the piston head edge. The at least one valve pocket may have a valve pocket depth T with respect to the piston head edge. The valve pocket depth T may fulfil the following condition with respect to the wall height H: 0.05 H<=T<=0.5H.

Abstract: A steel piston for an internal combustion engine may include a piston crown and a protective layer disposed on the piston crown. The protective layer may include an adhesion layer of Cr or CrN, which is present on a surface of the piston crown. The protective layer may include a functional layer, which is present on the adhesion layer. The functional layer may have at least one of (i) at least one layer (A) of CrN and (ii) at least one layer (B) of CrOn in the form of [(A)/(B)]a, and a may represent 1 to 100.

Abstract: A piston cooling jet includes a housing, a nozzle, a valve, a pressure chamber, a pressure adjusting passage, and a filter. The nozzle is provided to project outward from the housing, and capable of spraying oil toward a piston. The valve is capable of moving reciprocally inside the housing, and configured to receive a load due to a hydraulic pressure in an engine-side oil passage applied from a front side of the valve. The valve includes a valve-side oil passage that communicates with the engine-side oil passage. The pressure chamber communicates with the valve-side oil passage. The pressure adjusting passage is disposed between the pressure chamber and a space outside the housing. The filter is disposed in the valve, and configured to remove foreign matter that cannot pass through the pressure adjusting passage from oil passing through the valve-side oil passage.

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 of an internal combustion engine is disclosed. The piston may have a piston skirt having a central axis. The piston may also have a piston crown delimiting the piston skirt with a diameter D adjacent a top of the piston skirt. The piston crown may have an edge of the piston crown of width b and a piston crown recess of depth t. The piston crown recess may have a piston recess wall with an opening cross section of diameter d. At least one groove with an internal diameter dn may be provided within the edge of the piston crown. The at least one groove may run in a circumferential direction relative to the central axis. The internal diameter dn may be larger than the diameter d.

Abstract: A piston engine may include a heat pipe capable of transferring heat away from a portion of the piston engine such as a combustion section. The heat pipe may be included as part of a piston assembly, a cylinder, or both. The heat pipe may be filled with a suitable heat pipe fluid that may undergo a phase change such as, for example, water, ethanol, ammonia, sodium, other fluids or combinations thereof. Boiling and condensing of the fluid within the heat pipe may utilize the latent heat of the fluid during heat transfer. Multiple heat pipes may be used in some instances.

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

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

Abstract: The invention relates to a piston for an internal combustion engine made of an iron-based material, comprising a piston head and a piston skirt, the piston head comprising a piston base, a peripheral top land and a peripheral annular part comprising annular grooves. According to the invention, at least one annular groove comprises at least one insert made of an zinc-based material.

Abstract: A piston for an internal combustion engine may include an encircling ring section in a region of a piston crown. The piston may include a convection region, which has at least one cavity containing a heat transfer medium for dissipation of heat from the piston crown to an underside of the piston. The piston may include a heat insulating region, which is arranged between the ring section and the convection region and thermally insulates the ring section.

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 piston pin structure for an engine is provided, which suppresses integral resonance of a piston, a piston pin, and a smaller end part of a connecting rod with respect to a larger end part of the connecting rod on the combustion stroke, as well as suppresses an increase of noise on other strokes, and restricts the fixed dynamic absorber inside the piston pin from coming off and ensures a coming-off function. The piston pin structure may include a dynamic absorber including a fixed part fixed to a piston pin, a movable part extending in the axial direction of the piston pin, and a supporting part for swingably supporting the movable part with respect to the fixed part. A restriction mechanism for mechanically restricting the movement of the dynamic absorber in the axial direction may also be included.

Abstract: A piston structure for an engine is provided. The piston structure includes a piston for reciprocating within a cylinder, a connecting rod having a smaller-end part and a larger-end part in both ends, respectively, the smaller-end part coupled to the piston, the larger-end part coupled to a crankshaft, a cross-sectionally hollow piston pin coupling the piston to the smaller-end part, and a dynamic absorber provided inside the piston pin, including a fixed part fixed to the piston pin and a movable part pivotally supported by the fixed part, and for suppressing the piston, the piston pin, and the smaller-end part from integrally resonating with respect to the larger-end part of the connecting rod on combustion stroke. The dynamic absorber includes an assemblable dynamic absorber in which the movable part is formed by attaching a mass adjusting part to the fixed part.

Abstract: An engine includes a piston inside a cylinder, a crank shaft, a connecting rod, an oil dipper provided in a big end portion of the connecting rod, and a piston pin which connects pin boss regions of the piston to a small end portion of the connecting rod, and a crank case. The piston pin is rotatably movable with respect to the pin boss regions and the connecting rod. There are counter regions between the small end portion and the piston pin, a first counter region on a side closer to a tip portion of the connecting rod and a second counter region on a side closer to the big end portion of the connecting rod. The first counter region includes two ends located farther inward than two ends of the second counter region in an axial direction of the piston pin.

Abstract: A piston for a compression ignition internal combustion engine includes a piston body having a combustion face defining a combustion bowl, and the combustion face including a compound bowl surface and a compound rim surface. The combustion face is profiled to balance a combustion efficiency property of the piston with emissions properties of the piston, and includes a profile of rotation defining a convex curve segment bisected by the longitudinal axis, and a plurality of concave curve segments outboard of the convex curve segment. The profile of rotation further includes a compound rim profile defining a plurality of convex curve segments corresponding to an inner rim surface. The convex curve segment of the compound bowl profile defines a relatively small radius of curvature, and the plurality of convex curve segments corresponding to the inner rim surface define a relatively large radius of curvature.

Abstract: Disclosed is a piston (16) that is capable of not only suppressing the occurrence of knocking but also reducing cooling loss in an internal combustion engine in which a tumble flow is formed in a cylinder. The piston for the internal combustion engine in which the tumble flow is formed in the cylinder includes a non-adiabatic region (50) that is a region on a piston upper surface (35) brought into contact with the tumble flow during an intake stroke and has no insulating layer. The piston also includes an adiabatic region (52) that is a region on at least a part of the piston upper surface excluding the non-adiabatic region and has an insulating layer.

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 piston of an internal combustion engine is disclosed. The piston may have a piston sleeve with a centre axis and a piston base with a diameter D delimiting the piston sleeve at a top of the piston sleeve. The piston base may have a piston base rim of width b and a piston bowl with a depth t. The piston bowl may be designed as a pot bowl, which may have a piston bowl base and a piston bowl wall with a maximum diameter d4 adjoining the piston bowl base. The piston bowl may have an opening cross-section aligned symmetrically relative to the centre axis. The opening cross-section may have a minimum diameter da, which is smaller than the diameter d4. A flow cut-off edge designed as a nose may be formed in the opening cross-section and may project in the radial direction inwards over the piston bowl wall.

Abstract: A piston (1) for internal combustion diesel engine having a piston diameter of 180 to 650 mm, includes a top part (2) and a body part (3) connectable to each other, the top part defining, when installed in a cylinder of the engine, the piston side of a combustion chamber, and the body part having an aperture (30) for a gudgeon pin (4), bosses (32) for distributing forces, when in use, between the piston and the gudgeon pin, the body part having an interior (33), an outer surface (34) and operable connecting surfaces (35). The interior of the body part includes an interior wall (330) having a macro geometry of wavy (331) surface, where a wave has a length of 3 to 25 mm and a height of 0.3 to 3 mm, the wavy surface having a micro geometry measurable as a surface roughness of 5 to 9 ?m.

Abstract: A liquid cooled piston of an internal combustion engine includes a piston lower part and piston upper part which has a combustion chamber recess. These piston components are supported via joining lands which are spaced apart radially and together form a dividing plane, and are joined together with a material-to-material fit. In order to receive piston rings, the piston upper part has a ring area and includes an annular cooling channel which extends into the piston lower part and is connected to an inner cooling space via connecting channels. The cooling channel is adjoined by recesses which are oriented in the direction of a piston head, are configured as a blind hole and widen conically starting from the cooling channel as far as a recess bottom. The recess bottom can be of a pronounced undulating enlarged surface or a finely undulating configuration.

Abstract: A three section steel piston for two-stroke engines is provided. The piston is provided with an upper section, a middle section and a lower section. Piston ring grooves are formed into the upper and lower sections, and pin bosses with openings and skirts are formed into the middle section. The middle section has relatively thinner walls as compared to the portions of the upper and lower sections at the piston ring grooves to reduce the mass of the piston. A closed cooling gallery may be formed adjacent an upper combustion surface of the piston with the cooling gallery being defined at least partially by the upper section.

Abstract: A piston for an internal combustion engine is disclosed. The piston includes an upper surface configured to at least partly face a cylinder head of the internal combustion engine. The upper surface includes a combustion bowl surface, and a squish face having an internal edge disposed a first distance from the longitudinal axis along a radial direction. The combustion bowl surface includes a planar surface extending radially outward from the longitudinal axis of the piston, a first concave surface disposed outside the planar surface in the radial direction, the first concave surface having a first radius of curvature, and a second concave surface disposed outside the first concave surface in the radial direction, the second concave surface having a second radius of curvature, the second radius of curvature being smaller than the first radius of curvature.

Abstract: In order to machine at least one workpiece on a lathe, where the workpiece rotates in the lathe and the at least one region to be machined of the workpiece is machined with the aid of at least one tool of the lathe, where the tool is moved at least parallel to the rotation axis of the workpiece, where the tool is moved parallel to the rotation axis of the workpiece such that the machined region of the workpiece is formed in a rotationally asymmetrical manner with respect to the rotation axis of the workpiece after machining. Furthermore, the invention disclosure relates to a cooling duct to a piston wall, and to a combustion-chamber hollow of a piston and also to a lathe.

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: A piston for an internal combustion engine has a body including an upper combustion wall having an upper combustion surface; cylindrical outer wall with a ring belt region adjacent the upper combustion surface, and a closed annular cooling gallery located in radial alignment with the ring belt region. A cooling medium is contained in the cooling gallery. The cooling gallery has an inner surface including a radially outermost portion extending along the ring belt region. The outermost portion converges from the upper combustion wall toward a longitudinal central axis. During reciprocating motion of the piston, the cooling medium flows and remains in contact with the cooling gallery walls, thereby maximizing the capacity for heat to be transferred from the upper combustion wall to the contained cooling medium and from the cooling medium to the piston body, ring belt region and ultimately to the engine cooling system.

Abstract: A piston, piston ring and method of construction thereof is provided. The piston ring is L-shaped, having a first portion configured to extend upwardly from a ring groove of a piston along a top land of the piston and a second portion configured for receipt in the ring groove. The first and second portions of the ring have an enclosed hollow cooling chamber with a cooling medium disposed therein such that the cooling medium is free to flow internally to the piston ring groove and upwardly from the piston ring groove along the top land.

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 piston for an internal combustion engine has a lower piston part and an upper piston part disposed on the lower piston part. The upper piston part has a top land that runs around its circumference, and a ring belt that runs around its circumference. At least the upper piston part consists of a sintered material.

Abstract: A method for the production of a piston made of steel, for an internal combustion engine, in which the upper piston part is produced using the forging method, and the lower piston part is produced using the forging or casting method, and they are subsequently welded to one another. To simplify the production method and make it cheaper, the upper piston part is forged using the method of hot forming and of cold calibration, to finish it to such an extent that further processing of the combustion bowl and of the upper cooling channel regions can be eliminated.

Abstract: A cast light metal piston for an internal combustion engine may include a piston crown and a piston skirt adjoining the piston crown. The piston skirt may include two skirt walls arranged on a pressure side and a counterpressure side, respectively. The piston skirt may have two box walls connecting the skirt walls, which conically taper towards one another in a direction of the piston crown. The piston may include an annularly encircling cooling channel. A thickness of the piston crown may amount to a maximum of 4.5 mm.

Abstract: The present invention relates to a piston (10) for an internal combustion engine, having a piston head (11) having a piston crown (17), an outer circumferential cooling channel (21), an inner cooling space (22) disposed in the region of the underside (17a) of the piston crown (17), which is closed off with a separate closure element (23) that has at least one outflow opening (25) for cooling oil. According to the invention, it is provided that the closure element (23) and the inner cooling space (22) extend all the way to below the outer circumferential cooling channel (21).

Abstract: A piston for a free piston engine generator, comprising one or more elements arranged coaxially along a piston shaft wherein the length of the piston is at least five times its maximum diameter, wherein at least one of the elements is formed from a magnetically permeable composite material having isotropic electrical resistivity at least twice that of electrical steel this arrangement providing improved free piston position control, more consistent combustion and improved electrical conversion efficiency.

Abstract: A cooling channel piston has a radially circumferential cooling channel located behind a ring field. The cooling channel piston is forged from a steel material and the cooling channel is worked in by machining between an upper part below the ring field and a lower part above the piston bosses and the piston skirts. The cooling channel extends behind the ring field in the direction of an upper face of the upper part, it being provided that the cooling channel piston has above its piston bosses and piston skirts an outwardly oriented support region. A closing element, which closes the cooling channel after the production thereof, is fastened between the lower edge of the ring field and the support region.

Abstract: Provided is an aluminum alloy piston for an internal combustion engine. In the internal combustion engine, the piston moves back and forth in a sleeve made of grey cast iron or an aluminum alloy. Further, the piston, which is made from silver, silver alloy, copper, or copper alloy, is provided with a film that covers the scoring that is formed on the piston skirt and there are undulations in the surface of the film, formed from protrusions and depressions. There is a difference of 8-15 ?m between the lowest point of the depressions and the highest point of the protrusions. The pitch of adjacent protrusions corresponds to the pitch of projections in the scoring. In addition, the arithmetic average roughness (Ra) of the protrusion peaks does not exceed 60 nm.

Abstract: A piston for an internal combustion engine has a crown, a skirt extending from the crown, a pair of pin bosses, and a plurality of struts connecting the pin bosses to inner sides of the crown and skirt. An internal combustion engine having the piston is also disclosed.

Abstract: A forging method for producing a piston skirt having two skirt walls and two box walls connecting the skirt walls may include forging, to the piston skirt, the skirt walls at least slightly conically towards the outside of the piston skirt via a first forging die. The box walls may be forged to the piston skirt, wherein each box wall has a hub inside and a hub outside. The box walls may be moulded via a second forging die, wherein the hub outside of each box wall runs at least one of substantially parallel to the piston axis and slightly sloping to an outside of their hub inside towards a free end of the piston skirt to the outside. The skirt walls may be drawn, simultaneously with moulding of the box walls, into a position that is approximately parallel to the piston axis.

Abstract: A piston and method of construction is provided. The piston includes a top part fixed to a bottom part. The top part has an uppermost surface with annular inner and outer upper joining surfaces depending therefrom. The bottom part has a pair of pin bosses with pin bores aligned with one another along a pin bore axis; a pair of upwardly extending annular inner and outer lower joining surfaces and a combustion bowl wall. Inner and outer weld joints fix the inner and outer upper and lower joining surfaces to one another. An annular cooling gallery is formed laterally between the upper and lower joining surfaces. The inner weld joint joining the top part to the bottom part is located within the combustion bowl wall and configured to minimized the compression height of the piston.

Abstract: A piston for an internal combustion engine may include a plurality of pin bores for accommodating a piston pin. The pin bores may be transversely oval to a longitudinal axis of the piston. The pin bores may be formed in a circular cylindrical manner at a zenith of ?=0° and at a nadir of ?=180°. The pin bores may be formed in an oval manner with an oil-holding volume at an equator of ?=90° and ?=270°. The pin bores may include a transition between the equator and the zenith and between the equator and the nadir that runs in a continuous and differentiable manner.

Abstract: The invention relates to a piston (10, 110) for an internal combustion engine. Said piston comprises a piston head (11), a piston skirt (12) and a peripheral recess (24) between the piston head (11) and the piston skirt (12), an annular peripheral cooling channel (17), which is open towards the bottom and which is closed by a closing element (18), being provided in the piston head (11), and the piston skirt (12) having fillets (21) which are connected to the bottom of the piston skirt (11) and interconnected via bearing surfaces (23, 123). According to the invention, at least one projection (26, 126) is formed in the region of a free end face (25, 125) of the bearing surfaces (23, 123) and extends radially into a region of the cooling channel (17), said projection matching an opening (19) in the closing element (18) of the cooling channel (17).

Abstract: The invention relates to a method for determining a position of a piston (5) in a piston pressure accumulator (1) and a ON correspondingly designed piston pressure accumulator (1). A housing (3) accommodates a displaceable piston (5). An electrode arrangement (15) having a plurality of 4-point measurement electrode pairs (17) is provided on the electrically conductive housing (3) and is designed to determine a position of the piston (5) inside the housing (3) by measuring a distribution of an electrical resistance or potential between inner electrodes (21) when a current is applied to outer electrodes (19), depending on a position along the housing (3). The position of the piston determined from the measurement of the potential distribution can be used to determine or check a charge state of the piston pressure accumulator (1).

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 invention relates to a method for producing a piston for an internal combustion engine, wherein a section which in the finished piston has a cooling duct (14) and a piston ring groove is recessed at first, the later cooling duct is then covered, and finally material for accommodating the piston ring is applied, and which is characterized in that the later cooling duct is covered by a wire material which is provided in a length, greater than necessary for one single piston. A device for producing a piston for an internal combustion engine with an at first recessed section that in the finished piston has a cooling duct (14) and a piston ring groove, has a device for attaching a cover on the cooling duct and a device for providing wire material having a length greater than necessary for one single piston.