Adjustable manhole cover
CA 2117565 C · Owner: Sacchetti, Cesare · Inventors: Sacchetti, Cesare
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An adjustable manhole cover support frame that includes a base unit, a top support unit telescopically arranged on the base unit and screw jacks interconnecting the two units permitting selectively adjusting the relative telescopic position of the top unit on the base unit. The base unit has an open ended sleeve projecting upwardly from a flange utilized to secure the base unit to the top end of a manhole vertical conduit. The top support unit has a top annular plate from which depends three cylindrical walls defining a first outer cavity telescopically receiving the sleeve of the base unit and inwardly therefrom a second cavity with holes in the bottom, to receive the upper ends of …
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 August 24, 1994 and granted April 22, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 24, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 24, 2016.
- 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.