Expansible chamber apparatus with pairs of cylindrical rollers
CA 1104501 A · Owner: Hopkins, Walter M. · Inventors: Hopkins, Walter M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus having an alternately expanding and contracting chamber comprises at least one pair of cylindrical rollers each having an exterior surface in continuous rolling engagement with the surface of the other roller of the pair the rollers being rotatable along parallel axes and two, parallel side walls, with each one of the rollers also being in continuous rolling engagement with one of the side walls. A third wall is opposite the rollers and joins the two side walls wherein the chamber is defined between these walls and the pair of rollers, and is enclosed.
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
- Granted July 7, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 7, 1998.
- 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.