Conduit-making apparatus with a multiple diameter winding drum
CA 2354468 A1 · Owner: The Lamson & Sessions Co. · Inventors: Foos, George
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus is disclosed for making a conduit or pipe. An extruder (12) is provided for producing a strip (14) of continuous thermoplastic. A winding drum (10) receives the strip and helically winds the strip around the drum's perimeter to form a conduit having an inner diameter corresponding to the outer diameter of the drum. The drum (10) includes a core tube (36) surrounded by a plurality of rollers (20) which define the outer diameter of the drum. The rollers (20) rotate to advance the strip around the drum (10). A pair of detachable plates (30, 32) are provided for supporting said rollers. Each plate (30, 32) has a plurality of support structures for receiving and removably …
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 18, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 18, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 18, 2022.
- 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.