A dust bag and method of production
CA 2117902 C · Owner: Minnesota Mining And Manufacturing Company · Inventors: Van Rossen, Leonard M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A dust bag (60) comprises a filter bag consisting of a filter material. In a first wall portion (51) of the filter bag an inlet, opening (56) is provided through which the air flow to be cleaned gets into the filter bag, On the inner surface of the wall portion opposite the inlet opening, there lies a protective layer (48) of a resistant material of great tensile strength. This protective layer extends as a strip through the filter bag and prevents damage to the inner surface of the filter bag caused by particles striking the same.
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 March 24, 1993 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 24, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 24, 2015.
- 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.