出典:Wikipedia
出典:『Wikipedia』 (2011/08/05 15:26 UTC 版)
A machine tool is a machine, typically powered other than by human muscle (e.g., electrically, hydraulically, or via line shaft), used to make manufactured parts (components) in various ways that include cutting or certain other kinds of deformation. All machine tools involve some kind of fundamental constraining and guiding of movement provided by the parts of the machine, such that the relative movement between workpiece and cutting tool (which is called the toolpath) is controlled or constrained by the machine to at least some extent, rather than being entirely "offhand" or "freehand". Machine tools archetypically perform conventional machining or grinding on metal (that is, metal cutting by shear deformation, producing swarf), but the definition can no longer be limited to those elements, if it ever could, because other processes than machining may apply, and other workpiece materials than metal are common. The precise definition of the term varies among users, as detailed in the section. It is safe to say that all machine tools are "machines that help people to make things", although not all factory machines are machine tools.