Extension spring-type assembly for raising sectional door
CA 2228446 C · Owner: Mihalcheon, Arthur A. · Inventors: Mihalcheon, Arthur A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The assembly comprises an extension spring anchored at one end to a winch mounted to the door opening frame. A double-grooved pulley is mounted on a plate secured to the free end of the spring. A fixed second double-grooved pulley is mounted to the door frame. A pair of cables are anchored at one end to the door frame and extend in parallel to pass around the two pulleys. After the second pulley the cables separate and extend, down to the bottom corners of the door to which they are secured. Upon, release of the door latch with the door down the spring contracts and, through, the first pulley applies an equal pull to the two cables so that they move at the, same rate, thereby raising the …
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 January 30, 1998 and granted August 7, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 30, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 30, 2020.
- 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.