Patents by Inventor Rolf Stumm

Rolf Stumm 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: 6491292
    Abstract: A piston-cylinder assembly has a principal structural group including a cylinder and another principal structural group including a piston rod which has a part-length axially displaceably arranged within the cylinder. The piston rod adopts a default stroke position without external displacement forces acting on the piston-cylinder assembly, the default position being determined by positioning equipment. The positioning equipment includes at least one energy accumulator which acts in the inward and outward movement directions of the piston rod as a function of the stroke position of the piston rod. The at least one energy accumulator includes a tension spring arrangement and a compression spring arrangement.
    Type: Grant
    Filed: March 8, 2001
    Date of Patent: December 10, 2002
    Assignee: Stabilus GmbH
    Inventors: Rolf Stumm, Rolf Mintgen
  • Patent number: 6311813
    Abstract: An axially movable switching sealing ring within a groove having an axial width greater than the axial width of the ring, in particular in the piston of a piston-cylinder unit, where the switching sealing ring has sealing surfaces on its upper side surface, lower side surface and radial outer wall surface in each instance. The upper and lower side surfaces each have an axially relieved section adjacent the radially outer diameter of the ring, so that the upper and lower sealing surfaces are formed optimally by only part of the upper and lower side surfaces.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: November 6, 2001
    Assignee: Stabilus GmbH
    Inventors: Leo Lauderbach, Rolf Stumm
  • Publication number: 20010022133
    Abstract: A piston-cylinder assembly has a principal structural group including a cylinder and another principal structural group including a piston rod which has a part-length axially displaceably arranged within the cylinder. The piston rod adopts a default stroke position without external displacement forces acting on the piston-cylinder assembly, the default position being determined by positioning equipment. The positioning equipment includes at least one energy accumulator which acts in the inward and outward movement directions of the piston rod as a function of the stroke position of the piston rod. The at least one energy accumulator includes a tension spring arrangement and a compression spring arrangement.
    Type: Application
    Filed: March 8, 2001
    Publication date: September 20, 2001
    Applicant: Stabilus GmbH
    Inventors: Rolf Stumm, Rolf Mintgen