×

Process control method and apparatus

  • US 3,912,913 A
  • Filed: 04/08/1974
  • Issued: 10/14/1975
  • Est. Priority Date: 04/09/1973
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for controlling changes in the value of a process variable including the steps of producing electrically a digital number signal representing the desired value of the variable, adding to that number at successive equal intervals of time the positive or negative digital number representing the magnitude of a required change in the variable, to produce an updated desired value signal, and comparing the latter signal or an analogue of it electrically with a signal representing the measured value of the variable to obtain a control signal for regulating the value of the variable.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×