Safety system for detecting small objects approaching closing doors
US5925858A · kind A · utility
21Cited by
7References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1997 |
| Grant date | Jul 20, 1999 |
| Priority date | — |
| Expiry date | Jun 23, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B13/26
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A safety system for detecting small objects that approach closing doors comprising a transmitter stack, a detector stack, and a controller including instructions to detect small objects as the doors are closing. A transmitter or a group of transmitters from the transmitter stack are powered sequentially resulting in an output from the detector stack. The controller compares each output from the detector stack with an average of all the outputs plus a threshold value. The outputs that exceed the average plus threshold value trigger the safety system to reverse closing operation of the doors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.