Elevator control system
CA 1197635 A · Owner: Mitsubishi Denki Kabushiki Kaisha · Inventors: Watanabe, Eiki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An elevator control system has a converter for converting an AC power from a normal power source to a DC power having a variable voltage to an inverter for inverting the DC power from the converter to an AC power having a variable voltage and a variable frequency and an induction, motor energized by the inverter to drive an electric motor. When a power failure occurs on the normal power source as sensed by a power failure sensor, the converter is connected to an emergency power source to be fully wired to generate a DC power higher in DC voltage than that due to the normal power source.
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
- Granted December 3, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 3, 2002.
- 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.