Patent · US Expired

Computer-implemented method and apparatus for monitoring statistical process control data

US5392226A · kind A · utility

23Cited by
26References
28Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 17, 1993
Grant dateFeb 21, 1995
Priority date
Expiry dateJun 17, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B21/02
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A computer-implemented method and apparatus for monitoring a process operating under statistical process control (SPC). The computer displays a "target control chart" to represent SPC data from the process. The target control chart comprises a Specification Limits ball graphically depicting the specifications limits for the process, a Control Limits ball graphically depicting the control limits for the process, and a Data Population ball graphically depicting one or more characteristics of a sample population of the measured data values for the process. Once defined, the Specification Limits ball remains static, and its display is not altered. The Control Limits ball may be static, or may be re-positioned and re-sized as additional measured data values are included in the sample population. The Data Population ball is dynamic and is re-positioned and re-sized as additional measured data values are included in the sample population. The position of the Data Population ball on a Y axis of the target control chart is calculated by averaging all measured data values in a specified study length or moving window of the sample population. The diameter of the Data Population ball is calcul…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.