Patent · US Expired

Integral gain elevator door motion control

US4305480A · kind A · utility

9Cited by
4References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 27, 1979
Grant dateDec 15, 1981
Priority date
Expiry dateDec 27, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/45242
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

An elevator system includes a microprocessor-based cab controller mounted directly on an elevator car, which controls elevator door motion in response to a velocity error indicative of the difference between the actual elevator door velocity and a desired dictated door velocity in accordance with a velocity profile. The door motor is driven in response to signals generated as a function of the velocity error, both with proportional gain and with integral gain. However, the integral gain component of the motion command signal is set to zero if the velocity error changes the sign of its polarity, which is indicative of overcompensation. Similarly, if the velocity error is below some acceptable magnitude, no integral gain is provided. An exemplary elevator system, an exemplary microprocessor-based controller, and logic flowcharts for an overall door control program, illustrative of an environment of the invention, as well as details of the invention, are disclosed herein.

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