Photoreflective elevator call button
US5914466A · kind A · utility
5Cited by
4References
2Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 31, 1997 |
| Grant date | Jun 22, 1999 |
| Priority date | — |
| Expiry date | Dec 31, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/968
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An elevator call button senses the position of a push button by means of a photoreflective sensor, thereby eliminating the need for a mechanical switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.