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:
Nov. 16, 1993
Filed:
Dec. 31, 1991
Thomas J Schultz, Maumee, OH (US);
Gas Research Institute, Chicago, IL (US);
Abstract
A control arrangement is disclosed for a conventional, atmosphere heat treating furnace which is operated at high temperature and fitted with a vacuum pump to draw rough or soft vacuum levels when heating the work to heat treat temperatures. The control arrangement utilizes a hydrogen--inert gas furnace atmosphere continuously metered into the furnace to produce a reducing gas mixture to prevent oxidation of the work. If oxidation conditions are sensed, the mass flow is automatically increased while vacuum levels are maintained constant. A unique oxygen probe mounting arrangement is disclosed which enables a conventional oxygen probe to give fairly accurate and consistent readings for fast, automatic process control.