Counterbalance mechanism for vertical opening door
CA 2226808 C · Owner: Foucault, Pierre-Louis · Inventors: Vafaie, Foad; Krupke, Leroy G.; Fuller, Douglas R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A counterbalance mechanism for a sectional garage door includes an elongated shaft mounted above the door opening and supporting spaced apart cable drums connected to respective cables which are connected at one end to the door for exerting a counterbalance force thereon. Opposed torsion springs are connected to the cable drums at one end respectively, and to respective hub members which are axially slidable on but nonrotatable with respect to the shaft. The cable drums are provided with detachable bushing members for engagement with the support brackets. The shaft is connected to a non-reversible worm gear drive at one end. The worm gear drive may be actuated to selectively vary the …
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 January 12, 1998 and granted June 5, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 12, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 12, 2020.
- 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.