Rod or piston seal
CA 2131071 C · Owner: Carl Freudenberg · Inventors: Stein, Gunter; Arndt, Ernst-Moritz
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rod or piston seal with a seal body of polymeric material has a seal surface for, engagement with a relatively movable surface to be sealed which seal surface is, interrupted in the direction of movement by at last two circumferentially extending, grooves that are positioned at a selected distance from each other. The distance between, adjacent grooves is respectively covered by an intermediate web. The ratio A of the width, of the webs to the width of the grooves measured in direction of movement is 1:2 to, 200:1, the ratio B of the width to the depth of the grooves is 10:1 to 1:5 and the depth of, the grooves is about 1 to 200 micrometer. The seal is more economically …
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 August 29, 1994 and granted January 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 29, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 29, 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.