Patent · US Expired

Escalator passenger flow control

US4631467A · kind A · utility

15Cited by

3References

4Claims

0Family size

Assignee

OTIS ELEVATOR COMPANY · US

Inventors

Dietrich E. Herrmann · Vechelde, DE
Detlev Abraham · Berlin, DE

Key dates

Filing date	May 28, 1985
Grant date	Dec 23, 1986
Priority date	—
Expiry date	May 28, 2005

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02B50/00
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A variable-frequency, variable-voltage (VVVF) converter is interposed in the line between an AC source and an asynchronous escalator motor. Current to the motor is sensed to determine load in conjunction with a passenger detector and load simulating electronic system and the frequency and voltage of the converter are automatically adjusted in response thereto to control escalator speed. The system includes a converter to supply the asynchronous drive motor of the escalator with variable frequency and an appropriate control circuit for manual or automatic operation of the escalator at different speeds, which is equivalent to different motor frequencies.

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