Differential reflectometery for position reference in an elevator system
US5783784A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 1996 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | Nov 19, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B1/40
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
An apparatus for determining if an elevator car is level with respect to a landing in a hoistway comprises a transceiver for transmitting a signal, a first reflector having a varying reflectance between a maximum reflectance end and a minimum reflectance end, a second reflector having a varying reflectance between a maximum reflectance end and a minimum reflectance end, and a processor. The first reflector transmits a first reflected signal in response to the signal transmitted by the transceiver and the second reflector transmits a second reflected signal in response to the signal transmitted by the transceiver. The first reflector and the second reflector are adjacently aligned such that the maximum reflectance end of the first reflector is adjacent to the minimum reflectance end of the second reflector, and the minimum reflectance end of the first reflector is adjacent to the maximum reflectance end of the second reflector. The processor determines if the elevator car is level with respect to the landing in response to the first and second reflected signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.