Recovery of components of waste plasterboard
CA 2039534 C · Owner: Bauer, Fred Michael · Inventors: Bauer, Fred Michael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for processing waste plasterboard consisting of sheets of paper or similar material adhered to a core of plaster of paris or the like, for recovering and separating the cover material from the gypsum of the core and for collecting each in a conveniently reusable form. A pair of rollers have parallel axes of rotation and are held to a variably close spacing under pressure while being counterrotated to grasp and crush pieces of plasterboard delivering the, paper and crushed gypsum core material to a vibrating screen which separates the two for separate collection and subsequent reuse as raw materials or for other purposes. A second crusher and screen may be used for …
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 April 2, 1991 and granted August 20, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 2, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 2, 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.