Abstract: A piston for internal combustion engines has a skirt coating, consisting of a wear resistant inner layer consisting of a polymer matrix having ceramic particles, aramide fibers and/or carbon fibers dispersed therein and an outer layer consisting of a polymer matrix having solid lubricants dispersed therein and an outer layer consisting of a polymer matrix having solid lubricants dispersed therein.

Abstract: produced according to the method having a piston crown with annular grooves, a combustion-chamber bowl, and piston shaft having a pin bore for receiving a pin, wherein both a combustion-chamber rim and a combustion-chamber bowl base are melted and thereafter solidified.

Abstract: A mechanically controllable valve drive includes a cylinder head, a valve lift adjustment device comprising a rocker arm, a pivoted lever assembly comprising an end surface, an engagement element, and a bearing means. The pivoted lever assembly is mounted in the cylinder head via the bearing means so as to be movable. A gas exchange valve is configured to have the pivoted lever assembly act thereon via the end surface. A positioning device is configured to engage on the rocker arm. A valve clearance is arranged between the rocker arm and the engagement element. At least one adjustment device is configured to provide a valve clearance adjustment. The engagement element of the pivoted lever assembly is operatively connected to the rocker arm of the valve lift adjustment device via a work curve.

Abstract: A mechanically controllable valve operating mechanism includes a cylinder head, a camshaft, a transmission arrangement mounted to move in the cylinder head via a bearing device. A gas exchange valve has the transmission arrangement act thereon. A valve-lift adjusting device comprises a rotatable adjusting element with an eccentric element having two base points and a peak contour, and at least one further eccentric element. The valve-lift adjusting device acts on the transmission arrangement so that different valve-lift positions are settable. The transmission arrangement is connected to the valve-lift adjusting device and to the camshaft. The at least one further eccentric element of the rotating adjusting element is arranged so that at least two peak contours are provided so that, depending on a rotational angle ? of the rotating adjusting element, the eccentric element or the at least one further eccentric element engage with the transmission arrangement.

Abstract: A method for producing a one-piece, lightweight piston consisting of steel and having a small compression depth (S) forms piston with at least one cavity in a shaft aperture region. A piston blank is produced in a first step using a forging or casting method. To form a cooling channel between an annular region and a combustion chamber recess an annular section is formed in one piece onto the wall of a cooling channel in the vicinity of the piston base. The joint produced between the annular section and an outer wall of the cooling channel is sealed by welding.

Abstract: A method for producing a cooling channel system for an internal combustion engine, which has a cooling channel in the piston crown. The piston crown is adjoined by a lower piston part having a piston boss, pin bores and piston skirts. Firstly, a piston blank having a peripheral collar projecting radially in the region of the piston crown is produced, wherein the collar, forming a subsequent ring zone wall is then reshaped and, in a transition area between the piston crown and the lower piston part, a contact area for the collar is formed, and the collar is reshaped in such a way until the outer radially peripheral edge comes very close to or completely into contact with the contact area in order to form a closed cooling channel. Following the reshaping, the end region of the ring zone wall forms a defined gap (X) with respect to the upper edge of the piston skirt.

Abstract: A piston with a piston boss in which a piston-pin bore is provided for accommodating a piston-pin. The piston-pin bore widens in the direction of a piston of a piston inner area with the widening above a bore axis with regard to a piston stroke axis, is less than the widening below the bore axis or vice versa.

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

Abstract: The invention provides water-soluble salt cores which are produced by compacting a mixture of water-soluble salts and a binding agent, under pressure and subsequently subjecting them to heat-treatment. The binding agent is an inorganic phosphate or a mixture of inorganic phosphates having a proportion of between 0.5 and 10 wt. % of the mixture.

Abstract: A method for processing a constructed, liquid-cooled piston of an internal combustion engine, the piston including an upper piston part and a lower piston part, which are supported by a joining plane and are connected to each other in a bonded manner. An electrochemical method, such as electrochemical machining, is used to produce a passage opening or a hole in the piston. By means of the method, material is selectively removed after the completion of the upper part piston, the lower piston part, or the piston after the two piston parts have been joined. The electrochemical machining allows an arbitrarily geometrically designed topography having at least one passage opening, a hollow, or an oil pocket in cooling areas or non-cooling areas to be created on the piston.

Abstract: A piston of an internal combustion engine has a piston crown with annular grooves and a shaft part disposed on the piston crown. The shaft part has bearing shaft wall sections which are connected to one another via inclined connecting walls which are retracted with respect to the outer diameter of the piston. Piston-pin bosses for accommodating a piston pin are disposed in connecting walls. The connecting walls are retracted at such an angle that, in progressing from the lower edge over an intermediate region which lies further back than the lower edge, into an end region which lies further back than the intermediate region the connecting walls to over flush into a hub supporting region below the piston crown.

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 preferably 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 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 process for hardening an annular groove of a piston head of a piston of an internal combustion engine by means of laser beams, in which, at least the annular groove to be hardened is provided before or directly during the hardening process with a coating which absorbs the energy of laser beams. The coating is subsequently irradiated by the laser beams. The absorbing layer can be a manganese phosphate coating or is formed in situ by treating the component surface with a process gas comprising oxygen and inert gas. Furthermore, the laser beams are directed at the piston during hardening at an oblique angle to the direction of rotation. The advantages achieved are avoidance of reflections and undesirable hardening of the bottom of the groove, an increased degree of absorption and reduced distortion of the piston.

Abstract: A method for producing a piston of an internal combustion engine, wherein the piston has a combustion bowl including a combustion bowl rim. The combustion bowl rim is hardened by being remelted in a first step by means of an inductive energy supply and, in a further step, by a laser beam. The beam can be deflected during a rotary, progressive motion relative to the piston.

Abstract: The invention provides water-soluble salt cores which are produced by compacting a mixture of water-soluble salts and a binding agent, under pressure and subsequently subjecting them to heat-treatment. The binding agent is an inorganic phosphate or a mixture of inorganic phosphates having a proportion of between 0.5 and 10 wt. % of the mixture.

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: A piston, especially a cooling channel piston of an internal combustion engine, has an upper part and a lower part which can be produced separately from each other and subsequently be assembled. The upper part has at least three radially peripheral joining webs and the lower part likewise at least three radially peripheral joining webs. During assembly, the webs are put together and connect the upper part firmly to the lower part.

Abstract: The invention relates to a process for producing a piston of an internal combustion engine, wherein a piston blank is cast from an alloy of aluminium and silicon with the addition of copper fractions and is then finished, wherein the invention provides that the maximum fraction of copper in the alloy, of aluminium and silicon is 5.5%, and that fractions of titanium (Ti), zirconium (Zr), chromium (Cr) or vanadium (V) are admixed with the alloy of aluminium and silicon.

Abstract: A piston of an internal combustion engine includes a top part produced from steel and a bottom part, which are integrally bonded in the region of a contact geometry via joining webs by a friction weld to form a structural unit. At least one cooling duct permeated by a coolant is integrated in the piston, wherein a lubricating oil of the internal combustion engine passes as the coolant into an inlet opening via a free jet of an injection nozzle, flows through the cooling duct and leaves the cooling duct via an outlet opening. For the introduction of the coolant into the cooling duct, the inlet opening is assigned a flow pipe which is inserted in the bottom part and protrudes from a cooling duct base, the opening of the flow pipe being arranged above the weld beads of the friction weld.

Abstract: A flux for application on and for reduction of oxide layers on a metal surface. The flux includes potassium fluoride, sodium fluoride, remaining moieties of water and gelatin. The can also include a reactant comprising moieties of at least one of the compositions of zirconium fluoride, lithium fluoride, sodium fluoride, potassium cryolite and potassium aluminum fluoride (KaAlF4), moieties of salts on the basis of at least one of the elements zirconium, lithium, potassium, sodium, bismuth boron and titanium and gelatin. The flux can be used in a method to reduce oxide layers on a metal surface by applying the flux onto the metal surface.