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機械是一種人為的實物構(gòu)件的組合。機械各部分之間具有確定的相對運動。機器具備機構(gòu)的特征外，還必須具備第3個特征即能代替人類的勞動以完成有用的機械功或轉(zhuǎn)換機械能，故機器能轉(zhuǎn)換機械能或完成有用的機械功的機構(gòu)。從結(jié)構(gòu)和運動的觀點來看，機構(gòu)和機器并無區(qū)別泛稱為機械。

機械是一種人為的實物構(gòu)件的組合。機械各部分之間具有確定的相對運動。機器具備機構(gòu)的特征外，還必須具備第3個特征即能代替人類的勞動以完成有用的機械功或轉(zhuǎn)換機械能，故機器能轉(zhuǎn)換機械能或完成有用的機械功的機構(gòu)。從結(jié)構(gòu)和運動的觀點來看，機構(gòu)和機器并無區(qū)別泛稱為機械。