Patent Yard Sign in
Expired Canadian patentCanada

Method of manufacturing low-core-loss grain oriented electrical steel sheet

CA 2045701 C · Owner: Kawasaki Steel Corporation · Inventors: Fukuda, Bunjiro; Sato, Keiji

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 method of manufacturing a low-core-loss grain oriented electrical steel sheet. Thread-like grooves are formed in a cold-rolled grain oriented electrical steel sheet having a final thickness of about 0.27 mm or less in a direction within the range of about 30° from the direction perpendicular to the rolling direction. The grooves and sheet satisfy the equation, log d 0.6 Ra + 0.4 where d is the groove depth (µm), and Ra is the mean surface roughness of the steel sheet cold-rolled to final gauge. The steel sheet is thereafter decarburization annealed and final texture annealed.

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 June 26, 1991 and granted May 13, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 26, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 26, 2013.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJune 26, 1991
GrantedMay 13, 1997
Term endedJune 26, 2011
Patent numberCA 2045701 C
Classification (IPC)C21D8/12 +2 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedJune 26, 1991Patent grantedMay 13, 1997Term endedJune 26, 2011

Sources & verification

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