Improvements in and relating to sifting screens
CA 2801867 C · Owner: United Wire Limited · Inventors: Robertson, Graham Alexander
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A frame over which woven wire mesh is to be stretched and secured to form a sieving screen and which can be used to screen solids from drilling mud recovered from down-hole when drilling for oil or gas. The frame is a rectilinear moulded plastics frame having edge regions by which it is secured in place in a shaker. Within the frame is a plurality of rectilinear windows formed by an orthogonal array of intersecting ribs also of moulded plastics material. Some of the ribs are internally reinforced by rigid metal members which extend orthogonally between hollow box-section members which define a sub- frame for reinforcing the four edge regions of the frame. The ends of the sub-frame members …
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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, 2005 and granted October 21, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 14, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.