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:
Sep. 18, 2018
Filed:
Oct. 28, 2016
Schaeffler Technologies Ag & Co. KG, Herzogenaurach, DE;
Joseph T. Griffin, Matthews, NC (US);
Earl Goldsberry, Cheraw, SC (US);
Shawn Pierce, Fort Mill, SC (US);
Al Thomas, Mint Hill, NC (US);
Schaeffler Technologies AG & Co. KG, Herzogenaurach, DE;
Abstract
A method of hardening a planetary gear shaft includes carbonitriding an outer peripheral surface of the planetary gear shaft and quenching the planetary gear shaft in oil at a temperature between approximately 120 and 150° C. The method also includes quenching the planetary gear shaft in a liquid at a temperature between approximately −70 and −120° C., and tempering the planetary gear shaft. After tempering, the outer peripheral surface of the planetary gear shaft includes a surface hardness of HV 832 or more and with the shaft material maintaining a hardness of at least HV 513 to a depth of at least 0.5 mm. High temperature tempering and induction hardening steps may be added to obtain soft ends of the shaft suitable for a staking operation.