Air lifting and balancing unit
CA 2359770 C · Owner: Hong, Peter Lee · Inventors: Mefferd, Thomas Arthur; Olson, Michael David; Hong, Peter Lee
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An air lifting and balancing unit (10, 80) including a cylinder (12, 82), a piston (21 107) in the, cylinder (12, 82), a ball screw (24 90) affixed to the, piston (21, 107), a ball nut (42 97) mounted for rotation, on the ball screw (24 90), a drum 45, 102) mounted on the, ball nut a chain (52, 114) driven by the drum (45 102), and centrifugally actuated brakes (62 117) mounted on the, drum (45, 102) for stopping rotation of the drum when the drum (45, 102) exceeds a predetermined acceleration either due to a loss of load or to a loss of air pressure applied to the piston (21, 107), and a pneumatic circuit (140) in communication with the cylinder (12, 82) for providing air pressure thereto …
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 December 8, 1994 and granted August 20, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 8, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 8, 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.