Control system for roll-up doors
US4939433A · kind A · utility
2Cited by
4References
1Claims
0Family size
Inventors
Key dates
| Filing date | Jul 11, 1989 |
| Grant date | Jul 3, 1990 |
| Priority date | — |
| Expiry date | Jul 11, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60J5/125
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A control system for controlling the direction of rotation of the reversible D.C. motor is provided which includes a master control circuit and a slave control circuit which is selectively operable. The control circuit permits the movement of the door to be arrested at any time and to be reversed at any time by operating the master control and allowing similar control by means of the slave control when it is activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.