Ultrasonic sensing and monitoring systems
US4628496A · kind A · utility
38Cited by
4References
58Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 27, 1984 |
| Grant date | Dec 9, 1986 |
| Priority date | — |
| Expiry date | Jul 27, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE05Y2900/132
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The presence of persons in a space is sensed with the aid of ultrasonic pulses which are sent out into the space when echoes of such ultrasonic pulses are received. Echoes attributable to the floor or to parts of a door in the space are timed out, and a remainder of such echoes is employed for sensing persons in the space. For example, sliding or revolving doors may be controlled and operated with the aid of such ultrasonic echoes, and limited access to secured areas may be provided thereby.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.