Ladder for fragile particulate commodities
CA 2045243 C · Owner: Dunnigan, Theodore J. · Inventors: Dunnigan, Theodore J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus for lowering particulate commodities includes a vertically disposed ladder extending from the upper end of the storage facility to the lower end of the storage facility. The ladder is formed of flexible planar sheets bent upon themselves to define substantially U-shaped chute member formed into a zigzag pattern such that the particulate commodities flow downward through the chute members passing from one chute member to the next chute member. The chute members are connected such that an opening is formed at the upper end of each chute member so that the commodities may exit the ladder once the level of the commodity within the storage facility has reached the upper end of a …
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 June 21, 1991 and granted April 23, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 21, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 21, 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.