Continuous filter
CA 2071965 C · Owner: Keillor, Peter T. Iii · Inventors: Kirksey, William A.; Keillor, Peter T. Iii
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Filtration process and filters for use with materials such as but, no limited to, polymeric melts, utilizing a band (18) of a filter medium sealed in a housing (10) by sealing rollers (24 26) to seal the polymeric, material from leaking to the outside of the housing. In one embodiment the sealing rollers make it possible to advance the filter medium through the housing continuously. In various embodiments the filter, medium can be advanced either by a take-up spool (32) or by driving the sealing rollers and the rate of movement of the filter medium through the housing can be controlled to maintain a constant pressure drop across the filter. Maintaining constant conditions through …
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 October 15, 1991 and granted August 8, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 15, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 15, 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.