Patent Yard Sign in
Expired Canadian patentCanada

Apparatus for triggering a plurality of thyristor devices

CA 2027155 C · Owner: Tsui, Huai-Chou · Inventors: Tsui, Huai-Chou

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

An apparatus for triggering a plurality of thyristor devices includes a full-wave rectifier circuit having a sinusoidal pulse output, a Schmitt trigger circuit to generate a constant amplitude pulse signal when the sinusoidal pulse output exceeds a certain triggering level, a clock pulse generator to generate a predetermined number of clock pulses within the duration of the constant amplitude pulse signal and an, address counter to receive the generated clock pulses. The address counter has a digital output corresponding to the number of clock pulses received. A read-only memory unit has digital data stored therein. The memory unit has a plurality of address lines to receive the digital …

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 October 9, 1990 and granted August 2, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 9, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 9, 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.
FiledOctober 9, 1990
GrantedAugust 2, 1994
Term endedOctober 9, 2010
Patent numberCA 2027155 C
Classification (IPC)H03K17/29 +1 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedOct 9, 1990Patent grantedAug 2, 1994Term endedOct 9, 2010

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.