Patent · US Expired

Door operation control apparatus

US4393342A · kind A · utility

24Cited by
5References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 9, 1981
Grant dateJul 12, 1983
Priority date
Expiry dateDec 9, 2001

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE05Y2900/106
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A motor for driving a garage door is controlled by a control unit, which counts the time required for the garage door to move between an upper limit switch and a lower limit switch. The control unit sets a comparison reference time on the basis of the time thus counted, and controls the motor in such a manner that the motor driving does not continue for a period of time longer than the comparison reference time.

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