Patent · US Expired

Gate operator method and apparatus with self-adjustment at operating limits

US6025685A · kind A · utility

22Cited by
8References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 11, 1997
Grant dateFeb 15, 2000
Priority date
Expiry dateJun 11, 2017

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE05Y2900/402
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An automatic gate operator includes an electric drive motor coupled by a drive train to a movable gate, and includes provision for measuring the coasting distance which the gate moves after shut off of the drive motor. This coasting distance varies both with the weight and momentum of the gate in comparison to frictional drag of the gate hardware, and the drag provided by the gate operator with the drive motor shut off, and also varies in response to a great number of other variables many of which are unpredictable. These other variables include such factors as wind, weather, temperature, wear, adequacy of lubrication, time interval since last operation of the gate operator, and off-level installation of the gate, for example. However, the coasting distance is measured and recorded, and is subsequently used as a predictor of gate coast on subsequent operation of the gate operator in order to coast the gate to a stop precisely at a selected limit position. The prediction improves with experience, and compensates over time for progressive changes in the operating circumstances and conditions of the gate.

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