Dual roller shade
CA 2178167 C · Owner: Hoffmann, Brian M. · Inventors: Hoffmann, Brian M.; Kovach, Joseph E.; Huntley, Gerald W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A double panel window shade is formed by shade panels wound on inner and outer coaxial rollers. The inner roller includes a shaft secured at each end and journaled in mounting brackets at each end of the inner roller. The outer roller includes end plates journaled on the inner roller shafts. The outer roller defines a slot for receiving and passing the inner shade when said outer shade is fully unrolled from the outer roller. Each shade panel includes a bottom rail. A pull cord is provided for raising and lowering the shades by rotating the rollers. The pull cord is operatively connected to the inner roller by a dual direction spring clutch. The rollers are formed by a pair of roller tubes …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 4, 1996 and granted February 1, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 4, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 4, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.