Elevator control system
US4516665A · kind A · utility
11Cited by
3References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 1, 1984 |
| Grant date | May 14, 1985 |
| Priority date | — |
| Expiry date | May 1, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J9/062
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An elevator control system has a converter for converting an AC power from a normal power source to a DC power having a variable voltage, an inverter for inverting the DC power from the converter to an AC power having a variable voltage and a variable frequency, and an induction motor energized by the inverter to drive an electric motor. When a power failure occurs on the normal power source as sensed by a power failure sensor, the converter is connected to an emergency power source to be fully fired to generate a DC power higher in DC voltage than that due to the normal power source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.