Patents by Inventor Hiromitsu Naitoh

Hiromitsu Naitoh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4437905
    Abstract: A cold-rolled low carbon steel strip is continuously annealed by rapidly heating the steel strip with a gaseous combustion product which has been prepared at a combustion air ratio of 0.8 or more but less than 1.0 in a direct fired furnace to a temperature of 500.degree. C. to an Ac.sub.3 point of the steel strip at an average heating rate of 30.degree. to 100.degree. C./sec to cause the thickness of a layer of oxides produced on the peripheral surface of the steel strip not to exceed 1,000 angstroms; by maintaining the temperature of the rapidly heated steel strip in a range of from 700.degree. C. to the Ac.sub.3 point, in a reducing atmosphere comprising 4% or more of hydrogen and the balance nitrogen, for at least 10 seconds, to reduce the oxide layer; by cooling the steel strip from at least 600.degree. C. to a desired temperature, at an average cooling rate of 10.degree. to 300.degree. C.
    Type: Grant
    Filed: January 13, 1982
    Date of Patent: March 20, 1984
    Assignee: Nippon Steel Corporation
    Inventors: Hajime Nitto, Hiromitsu Naitoh