Adjustable filter cigarette
CA 1255991 A · Owner: Philip Morris Products Inc. · Inventors: Nichols, Walter A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure A variable dilution cigarette, of the type having a filter with two relatively rotatable segments having slits in the plug wrapping and the tipping paper which rotate in and out of rotational registry to vary the dilution level, is provided which is insensitive to slight longitudinal misalignment of the slits. An array of longitudinal depressions is formed in one segment of the filter plug centered on the slit in the plug wrapping and ending short of both ends of the filter segment containing the slit. The depressions act as a plenum allowing the longitudinal flow of air between the slit in the tipping paper and the slit in the plug wrapping in case of …
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 June 20, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 20, 2006.
- 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.