Apparatus for a balanced three phase ac power supply in a computer having variable dc loads
CA 2068864 C · Owner: Tandem Computers Incorporated · Inventors: Neilson, Joseph S.; Tighe, Donald J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A balanced three phase AC power supply (12) for a computer system having unbalanced variable DC loads (34). AC to, DC converters (18a-c) utilize high power factor correction circuitry to impose a sinusoidal current loading waveshape (23) substantially in phase with the AC voltage (24). Each AC to DC converter outputs equal DC voltages maintaining a balanced loading on the AC power source. The design and organization of the power supply components make the supply fault tolerant when one phase (~A, ~B, ~C) of AC power or one AC to DC converter is lost due to malfunction or servicing.
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 November 21, 1990 and granted May 12, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 21, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 21, 2012.
- 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.