Cordless retractable roller shade for window coverings
US9353570B2 · kind B2 · utility
29Cited by
10References
28Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2012 |
| Grant date | May 31, 2016 |
| Priority date | — |
| Expiry date | Aug 31, 2032 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE06B2009/3222
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A cordless retractable shade including an operating system for the shade that varies a biasing force of a spring to counterbalance the shade. The bottom rail of a retractable shade can be raised or lowered, and due to the operating system remains in any selected position of the covering between fully extended and fully retracted, without the use of operating cords. The system includes a method of negating and reversing the spring bias effect at a strategic position whereby the flexible vanes of the shade can be adjusted between open and closed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.