Converter-powered drive for an elevator
CA 1235237 A · Owner: Inventio Ag · Inventors: Liechti, Hansruedi; Stanyard, Ray
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
INVENTORS: RAY STANYARD and HANSRUEDI LIECHTI INVENTION: CONVERTER-POWERED DRIVE FOR AN ELEVATOR ABSTRACT OF THE DISCLOSURE, A twelve-pulse converter has an a.c.-input and a d.c.-output which is connected with an armature via two thyristors of a charge-over circuit. An extinguishing circuit comprises a resistor, a capacitor an inductor and a, thyristor which is also connected with the armature via related diodes. A current transformer in the armature circuit causes ignition of the thyristor in the extinguishing circuit at the occurrence of excess current. The extinguishing capacitor is continuously connected with a charging circuit and is connected parallel to the thyristor of 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
- Granted April 12, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 12, 2005.
- 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.