Patent Yard Sign in
Expired Canadian patentCanada

Peer-to-peer register exchange controller for industrial programmable controllers

CA 2000445 C · Owner: Janke, Donald R. · Inventors: Bronikowski, Joseph T.; Gates, Dirk I.; Janke, Donald R.

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

A communication network for programmable logic controllers (PLC) wherein selected memory means of each PLC has at least two ports directly accessible by other PLC and certain registers of the PLC are identical. Each PLC further has an interblock gap timer to signal the PLC when its transmit time slice is to occur. The time slice consists of a block transmit time and an interblock gap time. The total update time has been optimized to enable efficient, high-speed transfer of blocks of data between the PLCs.

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 11, 1989 and granted February 4, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 11, 2009.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 11, 2011.
  • 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 11, 1989
GrantedFebruary 4, 1997
Term endedOctober 11, 2009
Patent numberCA 2000445 C
Classification (IPC)G06F12/00 +2 more

Sources & verification

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