Collapsible core for concrete pipe making apparatus
CA 2197630 A1 · Owner: Hawkeye Concrete Products Co. · Inventors: Schmidgall, Jon A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A collapsible core for concrete pipe making machines that are used in the dry cast process when lined pipe are to be produced. The collapsible core of the invention has a moveable front panel joined to two moveable side panels all of the panels being, connected to hydraulically powered linkage arrangements that will pull the panels straight back from the liner. The collapsible core is constructed so that when moveable panels of the core are retracted to collapse the core the core panels are guided along, radial lines of the core to pull the panels directly away from the pipe liner thus practically, eliminating the friction that causes bulging or pull out of the liner from the concrete pipe.
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 14, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 14, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 14, 2019.
- 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.