Abstract: A lapping apparatus lapping a work having a pre-machined surface comprises a lapping film which includes a thin substrate having a surface provided with abrasive grains, a shoe disposed at a back surface side of the lapping film, a shoe driving unit which drives the shoe toward the work in order to press the abrasive-grained surface of the lapping film to the pre-machined surface of the work, a rotational driving unit which drives the work rotationally, a detecting unit which detects the position of the rotating work in the rotating direction, and a controlling unit which controls the pressing force of the shoe driving unit so as to drive the shoe correspondingly to the position of the work in the rotating direction during machining.

Abstract: An apparatus and method for surface finishing a workpiece is disclosed as including a workpiece supporting mechanism supporting a workpiece having a target shaped periphery with a given width to be surface finished and a tool holder holding a surface finish tool in abutting contact with the target shaped periphery of the workpiece. A pressure applying mechanism is operative to apply a pressure force to the surface finish tool through the tool holder to cause the surface finish tool to be held in pressured contact with the target shaped periphery, with the pressure force exhibiting a given distribution pattern depending upon an axial direction of the workpiece. A drive mechanism rotates the workpiece to allow the surface finish tool to surface finish the target shaped periphery into a given geometrical profile, variably contoured along an axis of the workpiece depending on the given pressure distribution pattern.

Abstract: A film feeder (FF1) feeds a film (1), a first drive (20) rotates a work (W), a second drive (30) moves the work (W) relative to the film(1), a shoe set handler (40) handles the shoe set (2) to press the film (1) against the work (W), and a deterioration delayer (C) is configured to delay an abrasivity deterioration of the film (1).

Abstract: A four-cycle engine is provided with valve timing adjusters for adjusting opening and closing timing an and an exhaust valve. In medium- to high-speed ranges in medium- to high-load regions of the engine, a closing point (ExC) of the exhaust valve defined as a point of transfer from an acceleration portion to a constant speed portion on its valve lift characteristics curve is set to a point a specific period before an intake top dead center, and an opening point (InO) of the intake valve defined as a point of transfer from a constant speed portion to an acceleration portion on its valve lift characteristics curve is set to a point after the intake top dead center. In addition, the period from the closing point (ExC) of the exhaust valve to the opening point (InO) of the intake valve is made longer in the medium-speed range than in the high-speed range in the medium- to high-load regions of the engine.

Abstract: A four-cycle engine is provided with valve timing adjusters for adjusting opening and closing timing an and an exhaust valve. In medium- to high-speed ranges in medium- to high-load regions of the engine, a closing point (ExC) of the exhaust valve defined as a point of transfer from an acceleration portion to a constant speed portion on its valve lift characteristics curve is set to a point a specific period before an intake top dead center, and an opening point (InO) of the intake valve defined as a point of transfer from a constant speed portion to an acceleration portion on its valve lift characteristics curve is set to a point after the intake top dead center. In addition, the period from the closing point (ExC) of the exhaust valve to the opening point (InO) of the intake valve is made longer in the medium-speed range than in the high-speed range in the medium- to high-load regions of the engine.

Abstract: A method of measuring a lens comprises an aligning step of relatively aligning a plurality of specified annular zones on a surface of the lens with predetermined positions, and a determining step of determining an aspherical axis of the target surface aligned in the aligning step.