Hydraulic retarder and control
CA 2020867 C · Owner: Klemen, Donald · Inventors: Craig, James Thomas; Bitner, John R.; Cooke, Dennis M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure A hydraulic retarder and control composed of an accumulator, for rapid filling of the retarder; a pulse valve, for controlling fluid flow to and from the accumulator; a regulator valve, for limiting the inlet pressure to the retarder; and a pair of check valves for preventing fluid flow from the retarder to a pressure source and from the retarder to the accumulator. The pulse valve is controllable to provide rapid filling of the retarder, while the regulator valve will direct fluid from a secondary source to the retarder and control the pressure at the retarder inlet. The accumulator is filled from the main pressure source, between retard requests at a, rate that …
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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 July 11, 1990 and granted October 18, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 11, 2012.
- 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.