Drill string jarring and bumping tool
CA 2088288 C · Owner: Anderson, Clifford John · Inventors: Anderson, Clifford John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A jarring and bumping tool is provided having a, mandrel telescopically received within a barrel for relative longitudinal movement. Upper and lower seals form an oilcontaining annular space therebetween. The mandrel carries a free-floating annular primary piston which sealably engages a reduced-diameter piston fitting section of the barrel when passing therethrough. The mandrel also carries a secondary cylinder assembly with a transverse top wall and a downwardly extending annular secondary cylinder beneath the primary piston forming a piston chamber between the mandrel and secondary cylinder assembly. The mandrel also carries a spring which biases a free-floating annular secondary piston …
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 March 19, 1993 and granted October 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 19, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 19, 2015.
- 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.