Patents by Inventor Rolf Helle

Rolf Helle 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).

  • Steel piston ring
    Patent number: 7207571
    Abstract: In a corner portion (2) defined between an outer peripheral surface (4) and a lower-side surface (3) of a steel piston ring (1), a groove (5, 6) having either an approximately quadrangular shape with a length of one side of 0.05 to 0.4 mm or an approximately quarter circular shape having a radius of 0.05 to 0.4 mm is formed. A sharp edge (9) formed by the groove (5, 6) performs an oil scraping function and the groove (5, 6) works to reduce an oil pressure of a second land or a third land clearance between the cylinder bore and the piston.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: April 24, 2007
    Assignee: Kabushiki Kaisha Riken
    Inventors: Hideki Yoshida, Akira Sato, Rolf Helle
  • Steel piston ring
    Publication number: 20050184466
    Abstract: In a corner portion (2) defined between an outer peripheral surface (4) and a lower-side surface (3) of a steel piston ring (1), a groove (5, 6) having either an approximately quadrangular shape with a length of one side of 0.05 to 0.4 mm or an approximately quarter circular shape having a radius of 0.05 to 0.4 mm is formed. A sharp edge (9) formed by the groove (5, 6) performs an oil scraping function and the groove (5, 6) works to reduce an oil pressure of a second land or a third land clearance between the cylinder bore and the piston.
    Type: Application
    Filed: April 19, 2005
    Publication date: August 25, 2005
    Inventors: Hideki Yoshida, Akira Sato, Rolf Helle
  • Steel piston ring
    Publication number: 20040012153
    Abstract: In a corner portion (2) defined between an outer peripheral surface (4) and a lower-side surface (3) of a steel piston ring (1), a groove (5, 6) having either an approximately quadrangular shape with a length of one side of 0.05 to 0.4 mm or an approximately quarter circular shape having a radius of 0.05 to 0.4 mm is formed. A sharp edge (9) formed by the groove (5, 6) performs an oil scraping function and the groove (5, 6) works to reduce an oil pressure of a second land or a third land clearance between the cylinder bore and the piston.
    Type: Application
    Filed: April 2, 2003
    Publication date: January 22, 2004
    Inventors: Hideki Yoshida, Akira Sato, Rolf Helle