The invention relates to a valve rotating device (24) for a valve (10), preferably an intake valve or exhaust valve, of an internal combustion engine. The valve rotating device (24) has a valve restoring spring (22) for preloading the valve (10) toward a closed position of the valve (10) and a Belleville spring (40), which is arranged in operative connection between the valve restoring spring (22) and a support surface (44), which is lubricated with a lubricating fluid. An at least partially, preferably completely, peripherally extending collar portion (46) is arranged on a periphery, preferably inner periphery, of the Belleville spring (40). The collar portion (46) can have a wear-reducing effect and/or can make the valve rotating device (24) easier to install.

A powder admixture useful for making a sintered valve seat insert includes a first iron-base powder and second iron-base powder wherein the first iron-base powder has a higher hardness than the second iron-base powder, the first iron-base powder including, in weight percent, 1-2% C, 10-25% Cr, 5-20% Mo, 15-25% Co, and 30-60 wt. % Fe, and the second iron-base powder including, in weight %, 1-1.5% C, 3-15% Cr, 5-7% Mo, 3-6% W, 1-1.7% V, and 60-85% Fe. The powder admixture can be sintered to form a sintered valve seat insert optionally infiltrated with copper.

An internal combustion engine includes an engine body provided with a cylinder having openings for intake and exhaust, and valve bodies that open and close the openings, cam shafts provided with cam lobes that depress the valve bodies so as to open the openings, and bearing members that pivotally supports the cam shaft via lubricating oil. Each cam shaft includes cam journals pivotally supported by the bearing members, and a hollow bore extending in the axial direction of the cam shaft. When an area of the cam journal around the hollow bore is seen in a cross-sectional view perpendicular to the axial direction, a thickness on a projecting side of the cam lobe is X1, and a thickness on the opposite side to the cam lobe in the circumferential direction is X2, a relationship of X1>X2 is satisfied in at least a part of the cam journal.

A layer-sintered valve seat ring is disclosed. The layer-sintered valve seat ring includes at least two materials including a function material for a tribological contact with an opposite runner and a support material for the function material. The support material includes: C: 0.5 to 1.8% by weight; Cr: 3 to 16% by weight; Mo: 1 to 5% by weight; W: 0.5 to 5.5% by weight; V: 0.4 to 4.0% by weight; Cu: 12 to 25% by weight; Fe: 41.3 to 82.6% by weight; Mn: up to 0.6% by weight; Si: up to 1.8% by weight; and a remainder of production-related contamination in the form of at least one of Ni, Co, Ca, P, and S that are present in contents of <0.3% by weight each.

A lift-valve assembly, comprising a lift valve within a housing that includes a pressure segment, a mounting segment, a port segment, and a seat segment. The lift-valve assembly may receive a lift valve, and the housing including a valve seat and a biasing spring in a selectively replaceable configuration suitable for use in a conventional internal combustion engine in place of the conventional individual components, actuated by a cam actuating system, and controlling fluid communication between a combustion chamber and both intake and exhaust systems.

A method for producing a cam phaser for a cam shaft of an internal combustion engine, the cam phaser including a rotor, a stator and at least one cover, the method including arranging the at least one cover at the stator wherein the at least one cover is a flat circular piece of sheet metal and the stator including internal vanes and external drive tooth is integrally provided from one piece of metal; sealing the at least one cover at the stator by applying a ground axial face of the at least one cover to a ground contact surface of the stator; and after the sealing.

The disclosure includes manufacturing a semimanufactured cylinder head (3) having a shielding curtain portion (16g) and spraying metal powder (P) onto an annular valve seat portion (16f) using a cold spray method to form a valve seat film (16b). The shielding curtain portion (16g) projects in an annular shape from an annular edge portion of an opening portion (16a) of an intake port (16) or an opening portion (17a) of an exhaust port (17) toward the center (C) of the port. The annular valve seat portion (16f) is located on an outer side of the port than the shielding curtain portion (16g).

A method for producing a cam phaser for a cam shaft of an internal combustion engine, the cam phaser including a rotor, a stator and at least one cover, the method including arranging the at least one cover at the stator; and welding the at least one cover with the stator, wherein a first weld, a second weld and a third weld are formed at least on a large radius or on a small radius during the welding, and wherein the small radius is smaller than the large radius. The invention furthermore relates to a cam phaser for a cam shaft of an internal combustion engine, the cam phaser including a rotor; a stator and at least one cover.

A reciprocating piston engine, comprising an engine block having a piston cylinder; a piston disposed in the piston cylinder; an intake port to the piston cylinder, an intake valve to open and close the intake port to the piston cylinder; a rotatable crankshaft; a flywheel connected to the crankshaft which is rotatable with the crankshaft, the flywheel having a circumferential profile; and a cam lobe forming a portion of the circumferential profile of the flywheel wherein, during rotation of the crankshaft, the cam lobe acts on the intake valve to open the intake valve.

A camshaft adjuster is produced that includes a stator and a rotor, which is rotatable relative to the stator, wherein the stator and the rotor are produced with first planar surfaces on a first end face and with second planar surfaces on a second end face, which is formed to be opposite the first end face when viewed in an axial direction and wherein the rotor and/or the stator is or are produced according to a powder-metallurgical method, The first planar surfaces and the second planar surfaces of the stator and the rotor are ground or finished, and the lateral surface of the stator and the lateral surface of the rotor are left uncalibrated.