A copper alloy for engine valve seats manufactured by laser cladding improves wear resistance of the copper alloy. The copper alloy includes 12 to 24 wt % of Ni, 2 to 4 wt % of Si, 4 to 12 wt % of Mo, 15 to 35 wt % of Fe, and the remaining wt % of Cu and impurities.

A copper alloy for valve seats, and more particularly a copper alloy for valve seats with improved wear resistance, contains 12 to 24% by weight of Ni, 2 to 4% by weight of Si, 7 to 13% by weight of Cr, 20 to 35% by weight of Fe, and a balance of Cu and other impurities.

A drain port of a hydraulic oil controller is connected to an oil discharge portion. Each of partitions partitions between a corresponding one of drain oil passages and a corresponding one of a retard supply oil passage and an advance supply oil passage. Each of the drain oil passages connects between the oil discharge portion and a corresponding one of a retard chamber and an advance chamber. A recycle oil passage connects between: a portion of each drain oil passage located between the corresponding partition and the drain port; and the retard supply oil passage or the advance supply oil passage. A drain flow restrictor is formed in the portion of each drain oil passage located between the corresponding partition and the drain port. A passage cross-sectional area of the drain flow restrictor is smaller than a smallest passage cross-sectional area of the recycle oil passage and is constant.

A continuously variable valve duration apparatus includes a camshaft, a cam unit on which a cam is formed, a guide bracket including an upper guide boss, an internal wheel configured to transmit rotation of the camshaft to the cam unit, a wheel housing in which the internal wheel is rotatably inserted, wherein a guide thread is formed in a portion of the wheel housing, and of which a guide shaft is formed to be movably inserted into the upper guide boss, a worm wheel to which an internal thread engaging with the guide thread is formed in the worm wheel, and to which an external thread is formed thereon, a control shaft on which a control worm engaged with the external thread is formed, and an upper bushing mounted on a lower portion of the upper guide boss to support the guide shaft.

A method for producing a reduced friction sliding surface on a machine element includes applying a coating comprising amorphous carbon to a surface of the machine element and locally heating the coating with a laser. The coating is heated to a temperature below an evaporation temperature of the coating to achieve a local volumetric increase in the coating and a local increase in a layer thickness of the coating. A surface structure of the coating includes a multiplicity of elevations resulting from a local phase transformation of the coating from amorphous carbon into graphite due to the locally heating.

A valve seat ring for a gas exchange valve of a cylinder of an internal combustion engine includes: a one-part or multi-part main body defining a through-flow opening; and a valve seat region arranged on a portion of the main body in the region of the through-flow opening, a surface of the valve seat region forming a valve seat for a valve body of the gas exchange valve. At least into the main body at least one recess is introduced, which is at least partly filled with a solder material.

A valvetrain suitable for an internal combustion engine of a type that includes a combustion chamber, a moveable valve having a seat formed within the combustion chamber, and a camshaft. The valvetrain includes a rocker arm assembly having a rocker arm and an electrical device that either configures the rocker arm assembly or provides position feedback for a part of the rocker arm assembly. The valvetrain includes a framework that fits around a spark plug tube while holding a component of a circuit that includes the electrical device in a position adjacent the rocker arm assembly. The position may place the component in contact with or very close to the rocker arm assembly. This framework structure may effectively utilize the available space under a valve cover while facilitating correct positioning of the component in relation to the rocker arm assembly.

A camshaft phaser, including: a stator arranged to receive rotational torque, including a plurality of radially inwardly extending protrusions, and supported for rotation around an axis of rotation; a rotor including a plurality of radially outwardly extending protrusions circumferentially interleaved with the plurality of radially inwardly extending protrusions, and arranged to non-rotatably connect to a camshaft; a plurality of phaser chambers, each phaser chamber circumferentially bounded by a radially inwardly extending protrusion included in the plurality of radially inwardly extending protrusions and a radially outwardly extending protrusion included in the plurality of radially outwardly extending protrusions; an annular washer; and a target wheel including a first portion axially located between the annular washer and the rotor and in contact with the annular washer, arranged to detect a rotational position of the rotor for use in rotating the rotor with respect to the stator.

A beam-like crosshead for a valve train of an internal combustion engine is proposed for the transmission of a cam lift to two gas exchange valves. The crosshead has two side walls which are connected by a transverse wall, and, on an upper side of the transverse wall at its longitudinal center, a contact surface for a cam follower, and, on an underside of the transverse wall at each of its longitudinal ends, a valve contact surface. The crosshead is a reversed bowl-like hollow body which is produced from steel sheet using stamping/bending technology. From the transverse wall the side walls and, transversely at each longitudinal end, end walls hang in a finger-like manner. Cut edges between the side and end walls, starting from the transverse wall, form cut-outs.

A method for producing a valve seat ring via powder metallurgy may include compacting a powder mixture including 4% by weight to 16% by weight particles of cobalt to form the valve seat ring. The method may also include sintering the powder mixture after compacting the powder mixture. Before compacting the powder mixture, 80% of the particles of cobalt may have a particle diameter of approximately 4.4 μm to 17.5 μm.