Improved pipe joint construction and coupling therefor
CA 2132244 C · Owner: Shortman, Richard P. · Inventors: Shortman, Richard P.; Hawkins, Thomas W.; Hamilton, Larry J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A pipe joint and coupling construction particularly suited for joining large diameter plastic pipe as used in sewer relining. The construction comprises first and second sections of cylindrical pipe having axially aligned opposed end walls with a continuous groove formed in each end wall. The groove in each end wall is axially aligned with the groove in the opposed end wall and cooperates therewith to form a gasket receiving chamber. The coupling member is adapted to be mounted in the gasket receiving chamber for sealingly joining the pipe sections. It comprises a rigid annular core ring for mounting in the chamber to extend axially into each of the axially aligned grooves. A resilient …
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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 September 16, 1994 and granted January 26, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 16, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 16, 2016.
- 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.