4:3 perf conversion sprocket
CA 2057012 C · Owner: Mclendon, Donald C. · Inventors: Mclendon, Donald C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A sprocket assembly (20) which allows a film projector or any other film handling device to be readily converted to run film which is either 4-perf or 3-perf. The sprocket assembly (20) includes an outer cylindrical sleeve (22j having teeth for engaging the film perforations when the film is run and an inner, cylindrical sleeve (24) adapted to fit within and antirotationally mate with the outer cylindrical sleeve (22). The inner sleeve (24) also has teeth for engaging the film perforations. The inner sleeve (24) is mounted on a rotatable shaft (44) of the projector and the outer, sleeve (22) can be added or removed depending on whether the operator wishes to run 3-perf or 4-perf film. 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 February 6, 1990 and granted November 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 6, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 6, 2012.
- 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.