Abstract: CSP-3 with four parameters is one of the continuous sampling plans,however,the process capability is not taken into consideration when the inspection scheme is stipulated,selected and conducted,which leads to some deficiencies such as the outgoing quality for one process cannot be predicted and the outgoing quality for the multiple concurrent processes cannot keep consistent.For quantifying the outgoing quality and ensuring consistent output quality across multiple processes,the improved CSP-3 was proposed based on the estimator of the process conformance.The performance function of the average outgoing quality for CSP-3 was analyzed utilizing the differential theory,the monotonicity theory and the maximum theory.Thus the boundary identical equation and the contour identical equation were proposed for the specified in-control process,and there were infinite schemes simultaneously satisfying the boundary scheme condition and the contour scheme condition.The sole optimal CSP-3 scheme（designated as OCSP-3）was constructed for the in-control process based on the research of the mutual influence regularity of four parameters and the quality performance function of the different schemes.Some excellent characteristics had achieved by OCSP-3,such as the only optimal scheme,the quantifiable control of output quality,and the misjudgment risk was dramatically reduced by constructing the lower confidence limit of the process conformance.Compared with CSP-3,the advantages on the quality cost and risks for OCSP-3 were dominant.The effectiveness and superiority for OCSP-3 were demonstrated with the enterprise applications.

Key words: in-control process, process conformance, continuous sampling, average outgoing quality limit

摘要： CSP-3是拥有4个参数的连续抽样检验方案,但在制定、选择和运行方案时,没有考虑过程能力,导致输出质量不能量化控制、并行过程输出质量不一致等缺陷。为达到量化输出质量等目标,提出依据过程能力制定CSP-3方案。利用微分理论、单调性理论和最值理论分析CSP-3质量性能函数的变化规律,建立受控过程下边界恒等式和等值面恒等式。发现同时满足边界条件和等值面条件的方案有无穷多个。研究了4个参数的相互影响,对比了不同方案的质量性能函数,得到唯一最优CSP-3方案（命名为OCSP-3）。OCSP-3达成了最优方案唯一、可量化控制输出质量和用过程不合格品率置信限降低过程误判风险等功能。性能对比显示了OCSP-3在质量、成本和风险控制中的优越性。通过企业案例证明了OCSP-3的有效性。

关键词: 受控过程, 过程合格品率, 连续抽样检验, 平均检出质量极限