Method and apparatus for detecting abnormal characteristic values capable of suppressing detection of normal characteristic values

A method for detecting abnormal characteristic values of a plurality of products sequentially manufactured in a same manufacturing line, comprising:

• sequential manufacturing said products;
• determining whether or not a monotonic successive-increase tendency has occurred in a plurality of sequentially-obtained characteristic values of said products;
• determining whether or not at least a last one of said characteristic values is located within a control region narrower than an allowable region and outside a normal region narrower than said control region;
• and
• detecting an alarm state when said successive-increase tendency has occurred and said last characteristic value is located within said control region outside said normal region and adjusting said sequential manufacturing in accord with said detected alarm state when said alarm state is detected.

An apparatus for detecting abnormal characteristic values of a plurality of products sequentially manufactured in a same manufacturing line, comprising:

• a memory section storing a plurality of sequentially-obtained characteristic values of said products;
• a successive-decrease tendency determining section, executed by a processor, for determining whether or not a monotonic successive-decrease tendency has occurred in said plurality of sequentially-obtained characteristic values of said products;
• and
• a normal region determining section, executed by said processor, for determining whether or not at least a last one of said characteristic values is located within a control region narrower than an allowable region and outside a normal region narrower than said control region,
• thus detecting an alarm state when said successive-decrease tendency has occurred and said last characteristic value is located within said control region outside said normal region.

An apparatus for detecting abnormal characteristic values of a plurality of products sequentially manufactured in a same manufacturing line, comprising:

• a memory section storing a plurality of sequentially-obtained characteristic values of said products;
• a successive-increase tendency determining section, executed by a processor, for determining whether or not a monotonic successive-increase tendency has occurred in said plurality of sequentially-obtained characteristic values of said products;
• and
• a normal region determining section, executed by said processor, for determining whether or not at least a last one of said characteristic values is located within a control region narrower than an allowable region and outside a normal region narrower than said control region,
• thus detecting an alarm state when said successive-increase tendency has occurred and said last characteristic value is located within said control region outside said normal region.