【摘要】 田口提出的质量损失是指产品上市后给社会造成的损失,并用二次函数来描述这个损失,但没有指出这个损失具体是什么。产品投入服役使用后,由于受力、发热、疲劳和磨损等原因,产品质量开始劣化,质量特征发生变化,导致产品丧失功能而报废造成损失。定义质量损失为产品投入服役后因产品质量特征超出规定范围而导致报废所造成的损失现值,在此质量观基础上,应用资金折现原理建立基于服役寿命分布的产品质量损失模型,并提出基于质量特征公差要求的产品服役寿命分布密度函数计算方法。以轴套内径尺寸特征为例,深入讨论新模型中各参数对轴套质量损失的影响,并与田口质量损失模型、Teran质量损失模型进行比较分析,结果表明:该产品质量损失模型描述一种产品投入服役后给社会带来的实际损失,能够反映不同的产品在不同的服役条件和环境下产生的质量损失,比田口质量损失模型、Teran质量损失模型更符合实际。新质量损失模型将产品公差设计从产品设计制造阶段扩展到产品服役阶段,为产品质量在设计、加工、运行阶段等全寿命周期变化规律研究提供新视角。更多还原

【Abstract】 Taguchi defines product quality as a loss that a product imparts to society from the time the product is shipped,and describes the loss with a quadratic function,but does not indicate what the loss is specifically.The product quality characteristics are continually changing because of pressure,movement and attrition after the product is put into use,which will cause loss because of the product rejected and scrapped.The paper defines product quality losses as present worth of a loss caused by product obsolescence because its quality characteristics are out of specification after it’s put into service.On the basis of this view on quality,it establishes the present worth of quality losses model based on service life distribution with the principle of discounted cash flow,and proposes the calculation method of product service life distribution density function based on the technical requirements for tolerance of quality characteristic.It takes the interior diameter dimension characteristic of the shaft sleeve as an example to analysis the impact of various factors of the new model on the present worth of shaft sleeve quality losses,and contrast with Taguchi quality loss model and Teran present worth of quality loss model.The results show that the new model describes an actual loss that a product imparts to society after the product is put into service,and can reflect quality loss of different products in the different service conditions and environment,and is more realistic than Taguchi quality loss model and Teran quality loss model.The new model extends product quality assurance and tolerance design from the manufacturing stage to the service stage,and provides new perspective for quality variation in the life cycle of product design,processing,operation,et al.更多还原