A supply passage extends through an inner sleeve in a radial direction and conducts hydraulic oil received from a hydraulic oil supply source. An axial passage is located between an outer sleeve and the inner sleeve and extends in an axial direction. The supply passage opens to one end portion of the axial passage while another end portion of the axial passage is configured to connect with a valve timing adjustment device. A supply check valve is installed in the axial passage and is located on a radial side of the supply passage where a radially outer side of the inner sleeve is placed. The supply check valve enables a flow of the hydraulic oil from the supply passage toward the axial passage and limits a flow of the hydraulic oil from the axial passage toward the supply passage.

Provided is a heat treatment method for a cam piece, and the cam piece has an insertion hole into which a cam shaft is inserted, a base portion configuring a base circle of a cam, and a nose portion configuring a cam ridge. The heat treatment method for the cam piece includes: a first step of using a jig formed into a shape having a cavity, the jig being inserted into the insertion hole such that the cavity is located between an inner circumferential surface of the nose portion of the cam piece and a central axis of the jig; and a second step of heating the cam piece from an outer circumferential surface side by high-frequency induction heating in a state in which the jig is inserted in the insertion hole of the cam piece.

A valve timing control apparatus for an internal combustion engine includes a driving rotation member to which rotation of a crankshaft is transmitted, a driven rotation member coupled to a camshaft so as to be rotatable relative to the driving rotation member, an electric motor having a motor output shaft to cause rotation of the driven rotation member relative to the driving rotation member, a cover member arranged axially facing a front end portion of the motor output shaft and an electromagnetic induction type rotational angle detection mechanism disposed between the motor output shaft and the cover member so as to detect a rotational angle of the motor output shaft. The rotational angle detection mechanism has a detected part provided to the front end portion of the motor output shaft and a detecting part provided to a portion of the cover member axially facing the detected part.

A method of charging a hollow valve with metallic sodium includes providing a workpiece, as a semi-finished product for a hollow poppet valve, in which a cavity has an upward opening at a free end of a valve stem at a working position; inserting a nozzle into the opening to feed an initial inert gas into the cavity by jetting the inert gas from the nozzle; moving up the nozzle to put a holder between the workpiece and the nozzle, the holder holding a rod-like metallic sodium; and inserting the nozzle into a first end of the holder while an additional inert gas is jetted into the cavity from the nozzle to push down the rod-like metallic sodium along with the inert gas from a second end of the holder into the cavity of the workpiece.

A valvetrain conversion kit for an engine can comprises at least one timing idler rim gear configured to be meshed with at least one of a crank gear of the engine and a cam gear of the engine. The kit can include a first timing gear chamber member having a plurality of engine mounting locations corresponding to a plurality of corresponding cover mounting locations on an internal combustion engine body. The first timing gear chamber member can be configured to be rigidly attached to an engine body at the plurality of engine mounting locations. The first timing gear chamber member can also include a timing idler rim gear shaft supported by the interior surface, the timing idler rim gear shaft having an exterior shaft surface where the exterior shaft surface is configured for rotatably supporting the timing idler rim gear.

When forming valve seat coats at opening portions (16a.sub.1 to 16a.sub.8) of intake ports (16) provided at a cylinder block mounting surface (12a) of a semimanufactured cylinder head (3), the nozzle of a cold spray apparatus moves along a nozzle movement path for air intake (Inp1) that is set between any two of the plurality of opening portions (16a.sub.1 to 16a.sub.8), while continuing to spray a raw material powder. When forming valve seat coats at opening portions (17a.sub.1 to 17a.sub.8) of exhaust ports (17), the nozzle moves along a nozzle movement path for air exhaust (Enp1) that is set between any two of the plurality of opening portions (17a.sub.1 to 17a.sub.8), while continuing to spray the raw material powder.

A two-stroke internal combustion engine has an engine block having a cylinder block and a cylinder head. The cylinder block defines a cylinder, an exhaust passage, and an exhaust valve passage. The engine also has a piston, an exhaust valve actuator operatively connected to at least one of the cylinder block and the cylinder head, and a reciprocating exhaust valve disposed at least in part in the exhaust valve passage. The exhaust valve has a shaft operatively connected to a valve actuator, and a blade connected to the shaft. A channel is defined along a face of the blade. The channel and a wall of the exhaust valve passage together define at least in part a valve passage. The valve passage permits flow of exhaust gas along the face of the blade. A width of the valve passage is at least a third of a width of the blade.

A drive-side rotor is rotated synchronously with a crankshaft. A driven-side rotor is rotated integrally with a camshaft. An internal gear section is formed at the driven-side rotor. An Oldham coupling includes: a driven Oldham flange that is formed at the drive-side rotor; a drive Oldham flange that is formed at the planetary rotor; and an Oldham intermediate that is configured to synchronize rotation of the driven Oldham flange and rotation of the drive Oldham flange while permitting eccentricity between the driven Oldham flange and the drive Oldham flange. There is satisfied a relationship of θ2<θ1 where: θ1 is a maximum tilt amount of the planetary rotor relative to the driven Oldham flange; and θ2 is a maximum tilt amount of the planetary rotor in a clearance formed at the Oldham coupling.

An object of the present invention is to provide a chain guide mechanism that can readily integrate all the components in a simple structure and enhance work efficiency during assembly or maintenance. The chain guide mechanism of the present invention is configured to be able to integrally support, on a frame, components including a plurality of sprockets, a chain, a fixed chain guide, and a pivoting chain guide. The frame includes a pivoting chain guide holding part that holds a mounting boss of the pivoting chain guide in a state of a loose fit. The pivoting chain guide holding part is configured to allow the mounting boss to be fitted therethrough from one side.

A system to attach valve seat inserts to an aluminum cylinder head of an automobile vehicle includes a cylinder head of an automobile vehicle engine having a valve seat portion. A valve seat insert is positioned in the valve seat portion of the cylinder head. A fusion bond is created between the valve seat insert and the valve seat portion by laser welding thereby fusing the valve seat insert to the valve seat portion.