Abstract: A light metal piston for highly stressed internal combustion engines has a combustion cavity in the piston head. In order to keep low the stresses at the edge of the combustion cavity without unnecessarily increasing the stresses in the support and hub of the piston pin, the piston has the following combination of characteristics: the combustion cavity (5) in the piston head (4) is not armoured; the bore (9) of each piston pin hub (8) is flared (cambered) towards the inner end of the hub in at toast the inner end (10) of a partial area X of the total length of the hub bore; the bore (9) of each piston pin hub (8) is designed as a molded bore (9) that is outwardly enlarged with a substantially conical shape at least in one partial area Z; the bore (9) of each piston pin hub (8) has on one side a slanted pocket (12) that starts at its inner end (10).

Abstract: A device for providing the running surfaces of the cylinders of internal combustion engines with a reinforcing coating. (e.g., a nickel dispersion layer including silicon carbide). The device is designed to hold and convey the cylinder block using a flow-trough process, and includes a baseplate (2) in which a pump (9) and the supply and discharge equipment (4-6) for the bath liquors are integrated. The device is transportable and enables the device to be used over a series of conventional treatment liquor baths.

Abstract: A piston for an internal combustion engine, particularly for motor vehicles. An oil-collecting chamber is disposed between the pin bosses above the pin boss bore. Oil collects within the chamber and is directed down onto the pin bosses, during reciprocating motion of the piston. The width of the chamber is approximately the same as the diameter of the pin boss bore.

Abstract: A piston having at least one piston ring in combination with a cylinder of a two-stroke internal combustion engine. The piston is made from an aluminum alloy and has a running layer covering at least 80% of the running surface of the piston. The running layer is made from resin-bound graphite. The piston ring has a crowned running surface and is made from cast iron or steel. The cylinder includes a running surface where at least the running surface is made from an aluminum alloy. The running surface has a roughness of less than 1 micron. The running layer on the piston has a thickness between 10 and 20 microns. The graphite particles which form the running layer have a size between 1 and 10 microns.

Abstract: An articulated oil-cooled piston for internal combustion engine extending along a longitudinal axis and including a piston skirt, a piston head with bosses, annular ribs and a piston pin disposed within the bosses for connecting the piston skirt and a connecting rod to the piston head. The piston head includes a ring belt which defines an outer border of an annular cooling oil duct. The annular cooling oil duct has a downwardly-facing opening which is covered by an annular plate. The annular plate is radially divided into plate parts, which are radially inserted into slots formed near the bottom end of the ring belt. When fully installed, the plate parts are disposed within a common plane which is oriented perpendicular to the piston axis.

Abstract: An oil filter has a cap screwed to the approximately upright arranged filter housing of the oil filter for the cleaning of lubricating oil, with a ring-shaped filter insert being detachably fastened on the cap and separating the outer inflow space from the inner flow-off space. In the lower zone of the filter housing, provision is made for a valve-like acting member, which is automatically opened with each change of the filter insert and serves for discharging oil that remained in the filter housing into an oil-collecting space via a discharge duct. A center bar is rotatably connected with the cap. The center bar is axially displaceable in a limited way and has in its zone close to the cap a piston-like flange, which is sealed against the filter insert and separates the inflow space from the flow-off space. The center bar has, in its lower end zone, the valve-like acting member cooperating with the discharge duct.

Abstract: A ring for protecting the edge of a combustion bowl disposed within a top surface of a light-alloy piston for a diesel engine. The ring is made of fine-grain carbon and serves as bowl edge armor. The ring is galvanically coated before being bonded to the remainder of the piston. The exterior surface of the bowl edge armor is coated with an antioxidation compound.

Abstract: A cooled multi-component piston is provided in which the hollow annular space in the piston head for the cooling oil is closed off underneath. This is achieved with a sheet-metal ring with a collet which fits in a recess in the piston-ring wall, the sheet metal ring being biased via a retaining clip against the shaft bush.

Abstract: A piston with at least one compression ring, a top end and a longitudinally extending axis for an internal combustion engine. The piston includes at least one compression ring groove defined by first and second spaced lateral surfaces for receiving the at least one compression ring. The first lateral surface is located nearest the top end of the piston. At least one of the first and second surfaces includes a plurality of profiles extending circularly around the axis and having a depth in the range of 0.003 mm to 0.015 mm and a width in the range of 0.02 mm to 0.2 mm.

Abstract: In a process for cleaning short mineral fibers in which the fibers contaminated with foreign bodies are separated from the foreign bodies, at least starting with a certain size, whereby mechanical damage to the fibers is avoided. For this purpose, the crude fiber material to be cleaned is added to a carrier medium which is set in a flowing motion and subsequently passed along a separation apparatus with at least one slot-like recess in the direction of the longitudinal extension of the recess. Thus, at least part of the carrier medium passes from an upstream side through the recess, together with the fibers, to a downstream side. In this way, a fiber filtrate is produced, of which the degree of purity is solely determined by the width of the recess. The carrier medium mixed with the crude material can be circulated in the cleaning process, with the carrier medium separated from the clean fiber filtrate being continuously returned to said circulation as well.

Abstract: The invention relates to a piston for an internal combustion engine. The piston has a longitudinally extending axis and ring grooves for receiving piston rings, and a separate piston head having a top and an annular cooling oil duct. A ring belt extends downwardly from the top of the piston head to define an outer border of the annular cooling oil duct and forms a first support facing in an axial direction. Bosses define an inner border of the annular cooling oil duct and form a second support facing in an opposite axial direction. The cooling oil duct has an opening and an annular plate supported on the first and second supports by spring tension. The annular plate closes the opening of the annular cooling oil duct to retain oil therein to cool the piston.

Abstract: A coated piston and a process for applying same to a piston of an internal combustion engine having a cylinder. The piston and cylinder are made primarily from a lightweight metal. Graphite bonded in cured resin is applied to the piston and forms a durable running layer.

Abstract: A piston for an internal combustion engine with a separate head and skirt which are joined by the piston pin. At least one of the upper lands has a reduced diametrical clearance with the cylinder wall in an area perpendicular to the pin direction. The bottom land has a reduced diametrical clearance with the cylinder wall in the pin direction. The lands are oval shaped, the bottom land optionally a truncated oval. At least one of the upper lands can have the shape of two ovals offset by 90.degree. like a cloverleaf.

Abstract: A method for the production of a molded casting, including the steps of providing a mold with a porous insert part which can subsequently be dissolved out. Placing the porous insert part having pores into the mold. Subsequently surrounding the porous insert part by a melt and then putting the melt under pressure. In the pore areas to be kept clear of the melt, gas pressure is maintained on the insert part which is equal to or slightly less than the melt pressure.

Abstract: A method for machining radial through-slots into a wall of a piston-ring groove which separates the ring groove from the piston interior. A piston for an internal combustion engine is provided in which the wall has varying thickness and is thinnest in the pressure and counterpressure sides of the piston. A cutting tool is held in a fixed position. The piston is rotated about its longitudinal axis. The rotating piston is brought into engagement with the fixed cutting tool so that slots of a predetermined axially height are machined into the ring-groove wall over the entire circumference of the piston. Also, radial through-slots are created only in the pressure and counterpressure sides of the piston.

Abstract: Safe and structurally simple design for a finebore machine with a turning tool (3) mounted on a boring bar (2), whereby the excursion of the turning tool is produced by a piezoelectric servomotor without any magnetic actuation. This is achieved in the following manner: (a) the turning tool (3) is lodged in a spring-mounted tool holder (4) which is made to deflect by a translatory driving servomotor (6); (b) the driving direction of the servomotor (6) is perpendicular to the operating direction of the turning tool (3); (c) the driving strength of the servomotor (6) acts on the one end of a connecting rod (8) which is lodged separately from the servomotor (6); (d) the other end of the connecting rod (8) abuts on the free mobile end of the tool holder (4) in a fixed position relative to the latter. The shape of the bore to be produced can be preset as an electronic image.

Abstract: A piston having a head with ring grooves, a skirt having hub bores, and a pin, with the following dimensions:L/D=0.45-0.8H/D=0.25-0.5A/D=0.3-0.5T/D=0.45-0.8whereL=maxium length of the pistonD=maximum diameter of the pistonH=compression heightA=maximum skirt height below the bottom ring groove in a peripheral area having the approximate same skirt height of at least 45 degrees on the major thrust face of the piston with approximately symmetrical division of this area on both sides of a plane extending perpendicular to the pin axis and passing through the longitudinal axis of the piston,T=diametrically opposite distance between the hub bore ends located radially on the outside.The skirt bulges along the axis of the piston and has an oval cross-section. An axis of the hub bores is offset slightly towards the major thrust face. The piston includes a horizontal slit, which separates the head from the skirt. In a polar plane perpendicular to the piston axis the skirt has a greater ovality on the minor thrust face.

Abstract: In an internal combustion engine, a piston has forged sections made of steel, especially in the piston head area, as well as at the hubs, and areas made of light metal, especially in the area of the piston skirt. The previously used quenched and drawn steel 42CrMo4V is to be replaced with a steel that has comparable properties but is more cost effective to manufacture. This replacement steel is a precipitation hardened ferrite-perlite steel.

Abstract: A piston for an internal combustion engine with a separate head and skirt which are joined by a piston pin. The ring belt extends downward from head and terminates above the pin. The space between the lower edge of the ring belt and a section of the head defines a cooling oil ring space. A depression is formed in the head and is partly defined by the section. The second land has the largest diameter and exclusively guides the piston. The height of the second land is in the range of three to seven percent of the piston diameter. The diametrical second land clearance is 1.5% to 2.5%. The diametrical third land clearance is one percent of the piston diameter. The diametrical top land clearance is in the range of 1.5 mm to 2.0 mm.

Abstract: A piston for an internal combustion engine with a separate head and skirt which are joined by a piston pin. The ring belt extends downward from the head and terminates above the pin. The space between the lower edge of the ring belt and a section of the head defines a cooling oil ring space. The head is provided with bores which extend from the cooling oil ring space upward toward the top of the head.