The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 05, 1977
Filed:
Sep. 10, 1975
Takeji Asai, Toyama, JA;
Kaishu Yamazumi, Toyama, JA;
Kabushiki Kaisha Fujikoshi, , JA;
Abstract
The method of this invention is directed to the heat treatment of an iron-containing article and comprises the steps of subjecting the article to an atmosphere comprising specific amounts of nitrogen, carbon, hydrogen, and carbon monoxide and heating this article in this atmosphere. The furnace comprises first and second interconnected chambers, with the first chamber being a heating chamber and the second chamber being a cooling chamber. The first chamber is selectively joined to the second chamber by a gate means. The heating chamber has a heating plate disposed therein arranged and configured to support an article thereon. The heating chamber further has heating means for heating the chamber disposed therein. The cooling chamber has means for positioning the article therein and at least one nozzle for selectively introducing nitrogen gas into the cooling chamber. The furnace also has a gas port extending through the heating chamber which is arranged and configured such that when a gas proceeds therethrough, gas impinges on the heating plate at a predetermined angle. By the use of the furnace and specific atmosphere, iron-containing articles, such as, for example, steel and the like, can be treated to improve their surface characteristics.