Variable-voltage variable-frequency elevator control apparatus
CA 1215185 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
A variable-voltage variable-frequency elevator control apparatus includes a circuit for consuming regenerated power produced during regenerative braking provided on the DC side of the apparatus rather than on the AC side. During regenerative braking with an emergency generating unit in operation regenera-, ted power is consumed by the consumption circuit on the DC side of the circuit and is prevented from being returned to the emergency generating unit. This prevents the production of voltage notches commonly produced during regenerative braking by thyristor commutation in conventional circuits. Because no voltage notches are produced, a reduction in the size of the emergency generating …
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 9, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 9, 2003.
- 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.