Helically wound reinforced ribbed composite structure
CA 2119035 C · Owner: Menzel, Stanley William Otto · Inventors: Menzel, Stanley William Otto
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A helically wound composite pipe produced by helically winding a plastics profiled strip (10) which has its adjacent edges interlocked, the strip (10) being provided with an array of lengthwise extending T-shaped ribs (15) spaced apart across its width and an elongate helical reinforcing member (11) wound around the outside of the pipe and having its marginal edges interlocking with the flange formations (14) of a pair of ribs (15) the reinforcing member , (11) having a central body portion of inverted U- or V-shaped cross section having a radial height greater than the height of the ribs (15) so as to substantially increase the effective external diameter of the pipe. Reinforcing …
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 September 30, 1992 and granted November 11, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 30, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 30, 2014.
- 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.