Patents by Inventor Robert W. Lehmann

Robert W. Lehmann 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: 9371749
    Abstract: A valve stem seal assembly has a metal retainer, an elastomeric seal, and a metal valve guide. The metal retainer and the elastomeric seal are attached to each other, and the elastomeric seal is in sealable contact with the metal valve guide, while the metal retainer is in metal-to-metal gripping contact with the metal valve guide. A stop may be formed in the metal retainer that cooperates with a shoulder formed in the metal valve guide in order to prevent over-installation of the assembly of the elastomeric seal with attached metal retainer, when this assembly is installed over the metal valve guide.
    Type: Grant
    Filed: February 1, 2013
    Date of Patent: June 21, 2016
    Assignee: Dana Automotive Systems Group, LLC
    Inventors: Timothy A. Hegemier, Alexander S. Williamson, Robert W. Lehmann
  • Patent number: 9052018
    Abstract: An eccentricity tolerant valve stem seal assembly includes an elastomeric seal having an upper metal retainer extending down and within an upper seal portion which has an inwardly directed sealing lip for contacting a valve stem. There are also a flexible middle and a lower seal portions. The lower seal portion is connected to a lower metal seal retainer that is disposed up to a lower edge of the middle seal portion. The flexible middle seal portion allows the upper seal portion to flex from an eccentric valve stem without losing the sealing function of the sealing lip. In cooperation with the above described structure, a separate cover may be in a tight tolerance fit with the lower seal retainer over top of the eccentricity tolerant valve stem seal, in order to limit axial displacement of the upper portion of the seal due to high manifold pressure.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: June 9, 2015
    Assignee: Dana Automotive Systems Group, Inc.
    Inventors: Timothy A. Hegemier, Robert W. Lehmann, Alexander S. Williamson
  • Publication number: 20130200574
    Abstract: A valve stem seal assembly has a metal retainer, an elastomeric seal, and a metal valve guide. The metal retainer and the elastomeric seal are attached to each other, and the elastomeric seal is in sealable contact with the metal valve guide, while the metal retainer is in metal-to-metal gripping contact with the metal valve guide. A stop may be formed in the metal retainer that cooperates with a shoulder formed in the metal valve guide in order to prevent over-installation of the assembly of the elastomeric seal with attached metal retainer, when this assembly is installed over the metal valve guide.
    Type: Application
    Filed: February 1, 2013
    Publication date: August 8, 2013
    Inventors: Timothy A. Hegemier, Alexander S. Williamson, Robert W. Lehmann
  • Publication number: 20130015625
    Abstract: An eccentricity tolerant valve stem seal assembly includes an elastomeric seal having an upper metal retainer extending down and within an upper seal portion which has an inwardly directed sealing lip for contacting a valve stem. There are also a flexible middle and a lower seal portions. The lower seal portion is connected to a lower metal seal retainer that is disposed up to a lower edge of the middle seal portion. The flexible middle seal portion allows the upper seal portion to flex from an eccentric valve stem without losing the sealing function of the sealing lip. In cooperation with the above described structure, a separate cover may be in a tight tolerance fit with the lower seal retainer over top of the eccentricity tolerant valve stem seal, in order to limit axial displacement of the upper portion of the seal due to high manifold pressure.
    Type: Application
    Filed: July 11, 2011
    Publication date: January 17, 2013
    Inventors: Timothy A. Hegemier, Robert W. Lehmann, Alexander S. Williamson
  • Patent number: 7438036
    Abstract: A valve stem seal having an annular valve body with an upper surface, a lower surface, and defining an aperture is disclosed. The valve body is positioned for selective sealing engagement with a valve stem. At least one orifice is disposed on an inner surface of the annular valve body between the annular valve body and the valve stem. The orifice controls the rate of oil flow between the annular valve body and the valve stem.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: October 21, 2008
    Assignee: Dana Automotive Systems Group, LLC
    Inventors: Eric W. Hesher, Robert W. Lehmann
  • Patent number: 6647943
    Abstract: A valve stem seal component overcomes potential orientation misplacement, particularly in cases where no valve stem seal is to be used on an adjacent valve. The component includes an integral locator feature for assuring proper installation atop a valve guide of an internal combustion engine. A plurality of such seal components are employed per engine, each component designed for insertion over at least the intake valve guide of each cylinder. Each component includes a valve stem seal module adapted to be installed over the intake valve guide. A locator is attached to the module via a radial connection portion that extends between the module and locator. The radial connection portion includes an arcuate edge that fits in only one orientation against a curvilinear edge of a boss on the cylinder head. In one described embodiment, the locator is a circular ring adapted to be installed over an exhaust guide.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: November 18, 2003
    Assignee: Dana Corporation
    Inventors: Mark A. Leimer, Mark A. Stamback, Robert W. Lehmann
  • Publication number: 20030024497
    Abstract: A valve stem seal component overcomes potential orientation misplacement, particularly in cases where no valve stem seal is to be used on an adjacent valve. The component includes an integral locator feature for assuring proper installation atop a valve guide of an internal combustion engine. A plurality of such seal components are employed per engine, each component designed for insertion over at least the intake valve guide of each cylinder. Each component includes a valve stem seal module adapted to be installed over the intake valve guide. A locator is attached to the module via a radial connection portion that extends between the module and locator. The radial connection portion includes an arcuate edge that fits in only one orientation against a curvilinear edge of a boss on the cylinder head. In one described embodiment, the locator is a circular ring adapted to be installed over an exhaust guide.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 6, 2003
    Applicant: Dana Corporation
    Inventors: Mark A. Leimer, Mark A. Stamback, Robert W. Lehmann
  • Patent number: 6230679
    Abstract: A valve stem seal assembly includes a resilient seal member mounted to a shell body having a downwardly extending skirt. At least one alignment pad or tang is provided in the skirt of the shell body for improved gripping of an outside diameter of a valve guide. In one embodiment, the alignment pad includes an inwardly projecting ramp portion connected to a generally longitudinally extending land portion and terminates in an inwardly projecting tang adjacent the land portion. In another embodiment, a valve stem seal assembly includes at least one tang having a generally arcuate end portion with a pair of spaced apart upwardly extending shoulders for gripping a valve guide.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: May 15, 2001
    Assignee: Dana Corporation
    Inventors: Timothy A. Hegernier, Mark A. Stamback, Robert W. Lehmann