Vertical lift device
US5351440A · kind A · utility
7Cited by
11References
16Claims
0Family size
Inventor
Key dates
| Filing date | Nov 27, 1992 |
| Grant date | Oct 4, 1994 |
| Priority date | — |
| Expiry date | Nov 27, 2012 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE05Y2900/40
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Apparatus for controlled raising and lowering of a barrier about a pivot point in which optimum control forces are applied to the barrier throughout its range of operation, and in which sensors are provided to prevent movement of the barrier against a resistive force to thereby prevent damage to the barrier, its operative mechanism, or an external object in its path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.