Operating unit for architectural coverings
US8893766B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 2008 |
| Grant date | Nov 25, 2014 |
| Priority date | — |
| Expiry date | Nov 3, 2029 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06B2009/905
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The invention relates to an operating unit (1) for architectural coverings, in particular roller blinds or shades. The unit (1) includes a stationary base member (37), a rotatable driving member (39), a rotatable driven member (29) and a brake mechanism (71, 73, and 75). The brake mechanism (71, 73, and 75) automatically arrests rotation of the driven member (29) in respect of the stationary base member (37), when not rotated by the driving member (39). The brake mechanism includes a first wrap spring (73), adapted to yield a predetermined minimum brake force, and at least one second wrap spring (75), different in size from the first wrap spring (73) and adapted to yield a supplementary brake force, which together with the predetermined minimum brake force amounts to a predetermined maximum brake force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.