A balance control system and method for a movable barrier operator
CA 2756755 C · Owner: The Chamberlain Group, Inc. · Inventors: Brookbank, Thomas A.; Fitzgibbon, James J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A balance control system comprises a motor (30) a transmission system providing connection between the motor (30) and the door (24) and adapted to move the door (24) between a closed position and an open position located above the closed position a counterbalance system (60) to reduce power required to lift the door (24) an apparatus to generate first signal representing a force used to move the door (24) from the closed position to the open position and to generate a second signal representing a force used to move the door (24) from the open position to the closed position and a controller (70) responsive to the first signal and to the second signal to indicate an imbalance of the door …
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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 April 8, 2003 and granted September 3, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 8, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 8, 2025.
- 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.