Patents by Inventor John Sofia

John Sofia 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: 7191521
    Abstract: The present invention provides for bevel gears having a localized and stable bearing contact. The localization of bearing contact is achieved by substitution of flat tooth surfaces with parabolic tooth surfaces. This is accomplished by either modifying line-contact directly or by using a generating parabolic cylinder during generation of the tooth surfaces. The actual contact area is spread over an ellipse centered around an instantaneous theoretical point of contact at the apex of the parabolic tooth surface. This localized bearing contact reduces the shift of the bearing due to assembly and manufacturing errors, thereby providing a more durable and quieter gear. Furthermore, the geometry of the gear enables creation of dies from which the gear may be forged. Transmission errors are modeled using a pre-designed parabolic function that coincides with the parabolic tooth surface design of the present invention.
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: March 20, 2007
    Assignee: American Axle & Manufacturing, Inc.
    Inventors: Faydor L. Litvin, Xiangshun Zhao, John Sofia, Theresa Barrett
  • Publication number: 20040154423
    Abstract: The present invention provides an advanced geometry for skew and straight bevel gears having a localized and more stable bearing contact produced by forging. The localization of bearing contact is achieved by substitution of flat tooth surfaces with parabolic tooth surfaces. This is accomplished by either modifying line-contact directly or by using a generating parabolic cylinder during generation of the tooth surfaces. The actual contact area is spread over an ellipse centered around an instantaneous theoretical point of contact at the apex of the parabolic tooth surface. This localized bearing contact reduces the shift of the bearing due to assembly and manufacturing errors, thereby providing a more durable and quieter gear. Furthermore, the geometry of the gear enables creation of dies from which the gear may be forged. Transmission errors are modeled using a pre-designed parabolic function that coincides with the parabolic tooth surface design of the present invention.
    Type: Application
    Filed: February 7, 2003
    Publication date: August 12, 2004
    Inventors: Faydor L. Litvin, Xiangshun Zhao, John Sofia, Theresa Barrett