Patents by Inventor Roland Stephan

Roland Stephan 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).

  • Publication number: 20240117825
    Abstract: An assembly for a fluid-filled piston-cylinder unit comprises a main body having an assembly longitudinal axis (24), a valve unit integrated in the main body and having an overflow channel, which valve unit seals the overflow channel when the assembly is moved along the assembly longitudinal axis in a first direction and releases the overflow channel, in dependence on the fluid pressure, when the assembly is moved along the assembly longitudinal axis in a second direction. Furthermore, the assembly comprises an outer seal element that is arranged on the main body so as to be moved along the assembly longitudinal axis, for abutting in a sealing manner against an inner surface of the housing, and at least one undercut element formed on the main body for engaging in an interlocking manner behind a mating element of the piston-cylinder unit.
    Type: Application
    Filed: January 28, 2022
    Publication date: April 11, 2024
    Inventors: Ludwig FELLNER, Manfred HOFMANN, Roland LÖSCHER, Florian STEPHAN, Wolfgang NAGL, Victor LIMPERT
  • Publication number: 20100021662
    Abstract: A method for the preparation of a silica slurry in water is described. The proposed silica slurry can be advantageously used as a constituent of a coating formulation for a paper comprising precipitated silica and/or silica gel as well as at least one further fine particulate pigment, in particular for an offset paper. The method includes, in the given sequence, the steps a) making a dispersion of the at least one further fine particulate pigment in water, b) adding the silica in dry powdery form to that dispersion.
    Type: Application
    Filed: January 30, 2008
    Publication date: January 28, 2010
    Inventors: Roland Stephan, Axel Laber, Detlef Spyra, Peter Resch, Mikel Van Avermaete
  • Publication number: 20080040922
    Abstract: Apparatus for making a metallic, non-rotationally symmetric ring with substantially constant wall thickness about its circumference, in particular a cam ring, from a circular ring, includes frame bed and a forming tool which is supported by the frame bed. The forming tool has an inner contour which approximates a finished contour of a non-rotationally symmetric ring, and includes two die members which are constructed in the form of two flat disks in opposite disposition and movable back and forth. Arranged in an area between the die members is an endless transport belt which is constructed to move in a production clock cycle and to move transversely to the die members. The transport belt has an upper strand extending in immediate proximity underneath the die members.
    Type: Application
    Filed: October 19, 2007
    Publication date: February 21, 2008
    Applicant: Mannesmannrohren-Werke AG
    Inventors: Roland Stephan, Wilfried Forster
  • Publication number: 20050204556
    Abstract: In a method of making a metallic, non-rotationally symmetric ring with substantially constant wall thickness about its circumference, in particular a cam ring, from a circular ring, a circular ring is mechanically machined on both inner and outer sides with an edge-shortening form element and then intermittently fed by a transport belt to an area between two continuously closing and opening die members. The transport belt is hereby positioned with its upper strand below the die members. After closing the die members, the circular ring is shaped through cold forming to a non-rotationally symmetric shape whereby the die members continue to maintain the closed position momentarily before being opened for removal of the non-rotationally symmetric ring from the area between the die members.
    Type: Application
    Filed: July 8, 2004
    Publication date: September 22, 2005
    Applicant: MANNESMANNROHREN-WERKE AG
    Inventors: Roland Stephan, Wilfried Forster
  • Patent number: 6936119
    Abstract: The invention is directed to a method and a device for producing metal, non-rotationally symmetric rings with a constant wall thickness along their circumference, particularly cam rings, starting from a hot-rolled pipe from which individual portions are severed, mechanically machined and subsequently hardened and tempered. Ring blanks of equal width are severed from the pipe and are mechanically machined on all sides, and the non-rotationally symmetric shape is produced by cold forming, the pipe or the severed ring blank having a structure suitable for cold forming.
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: August 30, 2005
    Assignee: Mannesmannrohren-Werke AG
    Inventors: Wilfried Förster, Joachim Schlegel, Dieter Wamser, Roland Stephan
  • Patent number: 6644151
    Abstract: Apparatus for the continuous, chipless separation of individual, identical pieces from a solid round workpiece, includes at least two cutting rollers, cooperating with one another, for separating and rolling the workpiece. Each of the cutting rollers is defined by a separating portion and has a coil, with the height of the coil of one cutting roller being equal or slightly greater than the radius of the workpiece in the separating portion, and with the coil of the other cutting roller so configured as to eliminate a collision in the separating portion with the coil of the one cutting roller.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: November 11, 2003
    Assignee: Mannesmann AG
    Inventors: Wilfried Förster, Roland Stephan, Joachim Schlegel
  • Patent number: 6615632
    Abstract: A parting tool for continuous chipless separation of identical parts from a rotation-symmetric workpiece, includes a cutting roller having a main body advancing a workpiece in a transport direction from an entry side to an exit side. The main body has a slip bevel at the entry side and a cutting screw including a screw thread having coils which define a helix line and are configured with an increase in height. The screw thread includes in series an entry portion, a substantially cylindrical primary portion and a separating portion, whereby the coils in the entry portion, primary portion and separating portion having different slope angle, with the slope angle determined by a combination of a thickness of the screw thread and a root width between two neighboring coils of the screw thread, wherein the increase in height of the coils correlates to the helix line.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: September 9, 2003
    Assignee: Mannesmann AG
    Inventors: Roland Stephan, Joachim Schlegel, Wilfried Förster
  • Publication number: 20030164210
    Abstract: The invention is directed to a method and a device for producing metal, non-rotationally symmetric rings with a constant wall thickness along their circumference, particularly cam rings, starting from a hot-rolled pipe from which individual portions are severed, mechanically machined and subsequently hardened and tempered. Ring blanks of equal width are severed from the pipe and are mechanically machined on all sides, and the non-rotationally symmetric shape is produced by cold forming, the pipe or the severed ring blank having a structure suitable for cold forming.
    Type: Application
    Filed: January 13, 2003
    Publication date: September 4, 2003
    Inventors: Wilfried Forster, Joachim Schlegel, Dieter Wamser, Roland Stephan
  • Patent number: 6536314
    Abstract: A device for continuous chipless separation of single identical rings from a tubular workpiece, includes at least two cutting rollers which are placed about the tubular workpiece, and which operate in a same direction and are interconnected by a positive engagement. Each cutting roller includes a basic body having opposite axial ends defining an entry zone and an exit zone, respectively. The basic body has a slip bevel at the entry zone, a calibrating section at the exit zone, and a cutting screw disposed between the slip bevel and the calibrating section and including a helical main thread portion with a conical entry part and a substantially cylindrical primary part in succession of the entry part, whereby the cutting screw has at least one additional thread which is disposed between threads of the main thread portion of the cutting screw.
    Type: Grant
    Filed: September 5, 2000
    Date of Patent: March 25, 2003
    Assignee: Mannesmann AG
    Inventors: Wilfried Forster, Roland Stephan, Dr.-Ing. Joachim Schlegel
  • Patent number: 6502486
    Abstract: A method for producing steel rolling bearing rings, starting from a hot-rolled tube, the structure of which is similar to a spheroidized structure and from which rings of the same continuous length are hot-cut while supplying a lubricant and, after cooling, are further processed. The hot-cutting takes place at a temperature below the transformation temperature of the rolling bearing steel used but above 720° C., with subsequent cooling in static air. From the blank ring a green or soft ring of a rolling bearing ring is produced with narrow tolerances of its shaped elements by an optimally timed multistage machining type of cold further processing operation, the main element of the cold further processing being a turning operation.
    Type: Grant
    Filed: February 4, 2000
    Date of Patent: January 7, 2003
    Assignee: Zannesmann AG
    Inventors: Karl Tenbrack, Wilfried Förster, Roland Stephan, Herbert Sommerfeld
  • Publication number: 20010022124
    Abstract: Apparatus for the continuous, chipless separation of individual, identical pieces from a solid round workpiece, includes at least two cutting rollers, cooperating with one another, for separating and rolling the workpiece. Each of the cutting rollers is defined by a separating portion and has a coil, with the height of the coil of one cutting roller being equal or slightly greater than the radius of the workpiece in the separating portion, and with the coil of the other cutting roller so configured as to eliminate a collision in the separating portion with the coil of the one cutting roller.
    Type: Application
    Filed: February 21, 2001
    Publication date: September 20, 2001
    Inventors: Wilfried Forster, Roland Stephan, Joachim Schlegel