Expired Canadian patentCanada
Multiple element swab cup having uniform ratio of length to cross-sectional thickness
CA 956231 A · Owner: Dresser Industries · Inventors: Blackwell, Henry W.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead 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 October 15, 1974. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 15, 1991.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedOctober 15, 1974
Term endedOctober 15, 1991
Patent numberCA 956231 A
Classification (IPC)F16J1/00 +2 more
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.