Two-way-driven 3-speed free wheel
CA 2046432 A1 · Owner: Chang, Dianlin · Inventors: Chang, Dianlin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A two-way-driven 3-speed free wheel which relates to a kind of multi-gear -changing mechanism for using on various kinds of pedal cycle, where in there are four kinds of catches: pawl hook-pawl, backward pawl and forward pawl are hinged on both sides of the sprocket wheel by small spindles, on one side are backward pawl and an outer ring, on the other side are forward pawl ratchet cone and, bearing collar, between outer ring and central gear are two or more planet pinions. As compared with prior art this invention has, following's advantages: the structure is simple the cost is lower, it, is facile to operate and to change speed.
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 July 8, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 8, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 8, 2013.
- 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.