Roller sifting and dispersing machine
CA 2292173 C · Owner: Gerhardt, Klaus · Inventors: Gerhardt, Klaus; Gawlitta, Werner
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns a roller sifting or dispersing machine for the classification or dispersing of wood chips fibers, or similar materials, having at least one roller set composed of several rollers axially aligned in parallel and having the same rotation direction; together these rollers form a roller bed that extends longitudinally at right angles to the rollers and is equipped with an input end for the material to be sieved and an output end for the course material whereby each roller's upper side turns toward the output end; the rollers are equipped with numerous annular grooves axially equi-spaced and separated by annular crosspieces that form the outer sheathing surface of the …
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 December 14, 1999 and granted March 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 14, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 14, 2021.
- 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.