Patents by Inventor Friedrich Witthaus

Friedrich Witthaus 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: 8182686
    Abstract: A hollow fiber membrane separation device with two flow spaces, of which a first space is formed by the capillary tube passages of a hollow-fiber bundle cast at its ends into a sealing compound, and a second space is formed by a housing enclosing the fiber bundle. The first space is sealed off by caps, placed on the sealing compounds, with seals running over the peripheral areas of the sealing compounds. The housing, into which the hollow-fiber bundle is drawn, at each end of its casing has tooth-like or pinnacle-like projections formed by axial notches or indentations running out freely. The tooth-like or pinnacle-like projections have extensions extending from the sides of the projections and extending to the adjacent tooth-like or pinnacle-like projection.
    Type: Grant
    Filed: June 8, 2006
    Date of Patent: May 22, 2012
    Assignee: Fresenius Medical Care Deutschland GmbH
    Inventors: Friedrich Witthaus, Gerhard Breith
  • Publication number: 20090301961
    Abstract: The present invention refers to a hollow fiber membrane separation device with two flow spaces, of which a first space is formed by the capillary tube passages of a hollow-fiber bundle cast at its ends into a sealing compound, and a second space is formed by a housing enclosing the fiber bundle, wherein the first space is sealed off by caps, placed on the sealing compounds, with seals running over the peripheral areas of the sealing compounds, and wherein the housing, into which the hollow-fiber bundle is drawn, at each end of its casing has tooth-like or pinnacle-like projections formed by axial notches or indentations running out freely. According to the invention, the housing has, between the tooth-like or pinnacle-like projections, extensions extending from said projections and extending to the adjacent tooth-like or pinnacle-like projection.
    Type: Application
    Filed: June 8, 2006
    Publication date: December 10, 2009
    Inventors: Friedrich Witthaus, Gerhard Breith
  • Patent number: 6832981
    Abstract: A multi-lumen tube arrangement for use in a centrifuge free of a sliding seal, the tube arrangement having at least two individual tubes which are rotated around one another around their longitudinal and/or their parallel axes. The rotation of the tubes takes place in this connection in opposite directions starting from a support position disposed approximately centrally in order to compensate the torques applied to the tube arrangement. A method for manufacturing such a tube arrangement is also decribed.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: December 21, 2004
    Assignee: Fresenius HemoCare GmbH
    Inventors: Friedrich Witthaus, Wolfram Weber
  • Patent number: 6716154
    Abstract: A centrifuge having a rotating frame, which is rotatably mounted on a stationary frame, and a separation unit mounted on the rotating frame, rotating about a central axis of rotation in the same direction of rotation as the rotating frame but at twice the rotational speed. A line for supplying and/or removing a fluid is connected to the separation unit and is guided in a loop about the separation unit to a stationary tie-in point. To support the line, at least one guide element having a bearing surface for the line is provided. The bearing surface of the guide element is formed by a rotating planar curve, where the radius of the respective circle of curvature contacts the curve at a point and increases with increasing distance between the contact point and the central axis of rotation. With this contour, abrasion over the entire contact surface is largely uniform, which thereby lengthens the lifetime.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: April 6, 2004
    Assignee: Fresenius HemoCare GmbH
    Inventors: Friedrich Witthaus, Wolfram Weber
  • Publication number: 20030045419
    Abstract: A centrifuge having a rotating frame, which is rotatably mounted on a stationary frame, and a separation unit mounted on the rotating frame, rotating about a central axis of rotation in the same direction of rotation as the rotating frame but at twice the rotational speed. A line for supplying and/or removing a fluid is connected to the separation unit and is guided in a loop about the separation unit to a stationary tie-in point. To support the line, at least one guide element having a bearing surface for the line is provided. The bearing surface of the guide element is formed by a rotating planar curve, where the radius of the respective circle of curvature contacts the curve at a point and increases with increasing distance between the contact point and the central axis of rotation. With this contour, abrasion over the entire contact surface is largely uniform, which thereby lengthens the lifetime.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 6, 2003
    Inventors: Friedrich Witthaus, Wolfram Weber
  • Publication number: 20020195154
    Abstract: The present invention describes a multi-lumen tube arrangement for use in a centrifuge free of a sliding seal having at least two individual tubes, which are rotated around one another around their longitudinal axes and/or their parallel axes. The rotation of the tubes takes place in this connection in opposite directions starting from a support position disposed approximately centrally in order to compensate the torques applied to the tube arrangement. Furthermore, a method for manufacturing a tube arrangement in accordance with the invention is described.
    Type: Application
    Filed: May 23, 2002
    Publication date: December 26, 2002
    Inventors: Friedrich Witthaus, Wolfram Weber
  • Patent number: 6200276
    Abstract: The present invention relates to a blood collecting device having a vacuum container and a cover which seals it. A blood filter is provided on the cover. According to the invention, the blood filter has a filter bottom which is designed to be flexible and/or is mounted movably.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: March 13, 2001
    Assignee: Fresenius AG
    Inventors: Wolfgang Biesel, Friedrich Witthaus
  • Patent number: 5814279
    Abstract: A centrifuge has a drive unit, a separation chamber which can be inserted into the drive unit, and a scanning device for recognizing the position of the separation chamber which is rotated by the drive unit. The separation chamber is constructed as a disposable chamber and is provided with a marker element which is arranged in a scanning region extending annularly around the rotation axis of the chamber. The position of a phase boundary window is detected by sensing the position of the marker with a phase boundary detector portion of the scanning device whereby the chamber can be inserted into the drive unit in any position.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: September 29, 1998
    Assignee: Fresenius AG
    Inventors: Wolfgang Biesel, Stefan Kreber, Henning Brass, Friedrich Witthaus, Artur Meisberger
  • Patent number: 5558769
    Abstract: A latching apparatus is provided for a bearing assembly in which at least three bearing rollers, each of which is supported in a rotating fashion on a bearing journal, are arranged rotationally symmetrical and lying in one plane and guide and support a bearing race between them. The bearing journals are arranged on a carrier device that is in turn supported in a rotating fashion on a central axle aligned with the axis of rotation of the bearing race, so that the bearing race and the carrier device can rotate at different RPMs. Such a bearing assembly on a rotating carrier is especially well-suited for a centrifuge, in which a separation chamber with a centrally secured line is to be driven in such a way that the tube does not become twisted.
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: September 24, 1996
    Assignee: Fresenius AG
    Inventors: Friedrich Witthaus, Wolfram Weber, Lothar Leick
  • Patent number: 5449022
    Abstract: Hose arrangement for a seal-less centrifuge having a soft inner layer and a hard outer layer and is formed by means of coextrusion.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: September 12, 1995
    Assignee: Fresenius, A.G.
    Inventors: Friedrich Witthaus, Carlo Lay, Wolfgang Biesel
  • Patent number: 5350514
    Abstract: The invention relates to a centrifuge comprising a separation chamber, with which a duct is permanently connected, a main rotor, on which the separation chamber is able to be bearinged in a relatively rotatable manner with respect to it, by means of a bearing arrangement, and a guide means on the main rotor for guiding the duct from the middle lower part of the separation chamber into a part at a higher level than the centrifuge. In order to be able to introduce the separation chamber into the main rotor in a simple and controlled manner the bearing arrangement has, within the main rotor, a part which is open or is able to be opened in a radial direction for the introduction of the duct into the main rotor.
    Type: Grant
    Filed: June 18, 1993
    Date of Patent: September 27, 1994
    Assignee: Fresenius AG
    Inventors: Friedrich Witthaus, Wolfram Weber, Wolfgang Biesel, Carlo Lay