Solenoid assembly
CA 2035924 A1 · Owner: Knight, John H. · Inventors: Fraser, Simon B.; Knight, John H.; Prain, Kenneth A. R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Solenoid Assembly" A solenoid assembly for the actuation of a valve or the like in a downhole tool comprises a first yoke (2) coil (52) and armature (18) and a second yoke (12) coil (53) and armature (32), the second armature (32) being fixed to a shaft (40) and having a planar end face spaced from a planar end face of the second yoke (12) by a second distance, and the first armature (18) being slidable upon the shaft (40) and having a non-planar end face spaced from a complementary non-planar end face of the first yoke (2) by a first distance less than the second distance. Energisation of the coils (52, 53) causes the first armature (18) to move towards the first yoke (2) until it mates …
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 February 7, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 7, 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.