Clutch-to-clutch control in an automatic transmission
CA 2026807 C · Owner: Hibner, John A. · Inventors: Lentz, Carl A.; Hibner, John A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In an automatic transmission upshifting is, controlled by ramping down the pressure in an off-going clutch associated with a high speed ratio and increasing the pressure in an on-coming clutch associated with a lower speed ratio. The on-coming clutch has commanded pressure at a maximum value for an initial fill time, a lower increasing ramp value during the ramp of the off-going clutch until the on-coming clutch starts to engage, and then a closed-loop control until the clutch reaches a synchronous speed. The closed-loop control parameter is on-coming clutch slip speed which is controlled to a calculated slip speed profile. The profile has a first steep slope and a final less steep slope so …
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 October 3, 1990 and granted May 17, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 3, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 3, 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.