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:
Jun. 25, 2013
Filed:
Feb. 03, 2011
Edward P. Becker, Brighton, MI (US);
Anil K. Sachdev, Rochester Hills, MI (US);
Emerson J. Adams, Sterling Heights, MI (US);
Thomas A. Perry, Bruce Township, MI (US);
Edward P. Becker, Brighton, MI (US);
Anil K. Sachdev, Rochester Hills, MI (US);
Emerson J. Adams, Sterling Heights, MI (US);
Thomas A. Perry, Bruce Township, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A valve assembly includes a tubular valve stem guide and a valve having a valve stem slidable in the bore of the valve stem guide. A lower valve stem seal has an annular body surrounding the valve stem and a skirt sealing with the valve stem guide. An upper valve stem seal has an annular body sealingly mounted on the valve stem and a skirt portion overlapping with the annular body of the lower valve stem seal during the reciprocating movement of the valve stem so that the upper and lower valve stem seals cooperate to prevent flow of oil to the bore of the valve stem guide. The valve stem is coated with a diamond-like carbon coating or a hard nitride coating, and the valve stem guide is of powered metal construction with approximately 1% by weight solid lubricant such as molybdenum disulfide or tungsten disulfide.