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【正文】 Parts of a lathe A lathe may or may not have a stand, which sits on the floor and elevates the lathe bed to a working height. Some lathes are small and sit on a workbench or table, and do not have a stand. Almost all lathes have a bed, which is (almost always) a horizontal beam (although some CNC lathes have a vertical beam for a bed to ensure that swarf, or chips, falls free of the bed). A notable exception is the Hegner VB36 Master Bowlturner, a lathe designed for turning large bowls, which in its basic configuration is little more than a very large headst At one end of the bed (almost always the left, as the operator faces the lathe) is a headstock. The headstock contains highprecision spinning bearings. Rotating within the bearings is a horizontal axle, with an axis parallel to the bed, called the spindle. Spindles are often hollow, and have exterior threads and an interior taper on the inboard by which accessories which hold the workpiece may be mounted to the spindle. Spindles may also have exterior threads and an interior taper at their outboard end, or may have a handwheel or other accessory mechanism on their outboard end. Spindles are powered, and impart motion to the workpiece. The spindle is driven, either by foot power from a treadle and flywheel or by a belt drive to a power source. In some modern lathes this power source is an integral electric motor. Accessories Unless a workpiece has a taper machined onto it which perfectly matches the internal taper in the spindle, or has threads which perfectly match the external threads on the spindle (two things which almost never happen), an accessory must be used to mount a workpiece to the spindle. A workpiece may be bolted or screwed to a faceplate, a large flat disk that m A workpiece may be clamped in a chuck, which mounts directly to the spindle or mounted on a mandrel. In precision work (and in some classes of repetition work), cylindrical workpieces are invariably held in a col
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