Filter insert
CA 2075623 C · Owner: Carl Freudenberg · Inventors: Lippold, Hans-Joachim
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The filter insert disclosed comprises a multiplicity of zig-zag-shaped pleated walls (43,44) made of a material which is permeable to the fluid to be filtered the fluid, passing through the filter insert from one edge of the zig-zag to the opposite edge. Projecting out from each zig-zag wall (43,44) towards a neighbouring wall (43,44) are projections (45) formed by embossing which, extend in the direction of motion of the fluid and, in particular are longer than they, are wide. The projections (45) from neighbouring zig-zag walls (43,44) abut each other, thus ensuring correct separation and increasing structural strength, and the abutting projections (45) of two zig-zag walls joined by an …
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 8, 1991 and granted January 19, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 8, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 8, 2013.
- 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.