Patent · US Expired

Field mounted control unit

US5333114A · kind A · utility

38Cited by
17References
37Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 1, 1993
Grant dateJul 26, 1994
Priority date
Expiry dateJul 1, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P90/02
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A smart field-mounted control unit, for controlling a process, receives signals and sends a command output over a two-wire circuit which powers the control unit. An input section receives the signal, which can be instructions representative of commands or instructions sets, process variables sensed by external control units or setpoints representative of a desired process state. The instructions are representative of a control requirement of the process and adjust a controlling section in the control unit to generate the command output in conformance with the control requirement. The command output can be a function of the difference between the process setpoint and a process variable, or a function of a linear combination of a process variable and its calculated time integral and time derivative functions. A sensing section in the control unit can sense and scale a process variable for generating the command output as well, The control unit can include a regulator section, controlled by the command output, which regulates application of a mechanical, hydraulic, pneumatic or electromagnetic force applied to the process.

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