Abstract: A valve lifter for an automotive internal combustion engine. The valve lifter includes a main body formed of one of an aluminum alloy and an iron-based alloy as a base material and having a top surface and a side surface which are respectively in slidable contact with opposite members in presence of at least one of a lubricating oil and a lubricant. Additionally, a hard carbon thin film is formed on the main body to cover the top surface and the side surface, the hard carbon thin film containing hydrogen atom in an amount of not more than 1 atomic %.

Abstract: There is provided a structure for connecting a piston to a crankshaft in an internal combustion engine, including a piston pin fitted into the piston, a crankpin integral with the crankshaft and a connecting rod having a piston pin bearing portion slidably engaged with an outer cylindrical portion of the piston pin and a crankpin bearing portion slidably engaged with an outer cylindrical portion of the crankpin. At least one of the piston pin bearing portion of the connecting rod and the outer cylindrical portion of the piston pin and at least one of the crankpin bearing portion of the connecting rod and the outer cylindrical portion of the crankpin have hard carbon coatings formed thereon with a hydrogen content of 20 atomic % or less.

Abstract: A piston for an internal combustion engine of an automotive vehicle. The piston has a piston ring and a piston skirt section each of which has a sliding section in slidable contact with a cylinder bore section of a cylinder block in presence of a lubricating oil. The cylinder bore section is formed of eutectic or hyper-eutectic aluminum alloy. Additionally, a hard carbon thin film is coated on the sliding section of the piston and contains hydrogen atom in an amount of not more than 1 atomic %. Here, the lubricating oil contains at least one selected from the group consisting of ashless fatty acid ester friction modifier, ashless aliphatic amine friction modifier, polybutenyl succinimide, derivative of polybutenyl succinimide, zinc dithiophosphate, and derivative of zinc dithiophosphate.

Abstract: A machine tool is used for machining a workpiece in the presence of a cutting oil composition. The machine tool includes a tool base and a hard carbon coating formed on the tool base. The hard carbon coating has 1 atomic % or less of hydrogen. The cutting oil composition contains a base oil and at least one of an ashless fatty-ester friction modifier and an ashless aliphatic-amine friction modifier.

Abstract: A cam lobe piece of a built-up type camshaft for an internal combustion engine. The built-up type camshaft includes a hollow shaft fixedly inserted in a shaft opening of the cam lobe piece upon diametrical expansion of the hollow shaft. The cam lobe piece comprises a base circle section having the shaft opening, and a cam lobe section formed integral with the base circle section.

Abstract: In a cladding method for covering a surface of a base metal with a metal for coating by using a processing apparatus for supplying a levigated coating metal together with irradiating a laser beam, in a first step, a first layer of cladding is formed on a surface of the base metal, and in a second step, a second layer is formed on a cladding starting portion in the first layer in an overlapping manner. In the second step, the processing apparatus is moved to an upper position which is more apart from the base metal than in the first step. In the above manner, since the processing apparatus forms the second layer of cladding with moving the processing apparatus upward, a processing point is moved upward together with motion of the processing apparatus. As a result of this, a generation of a defect in an overlapping portion of the cladding and a neighborhood thereof can be prevented.

Abstract: To improve the abrasion resistance by increasing the ratio of copper content in the copper-type alloy layer on the periphery of the ring groove of a piston. A peripheral groove having a section of a roughly large trapezoidal shape larger than that of the ring groove is formed preliminarily on the outer peripheral face of the piston. While the powder of a copper-type alloy material is supplied to this peripheral groove, the laser beam is irradiated to melt the powder, and a thickening layers is thus formed.