Patents by Inventor Stefan Marschall

Stefan Marschall 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).

  • Filter device, particularly reflux vacuum filter, and filter element for such a filter device
    Patent number: 8480774
    Abstract: A filter device, in particular a reflux vacuum filter, has at least one filter housing (7) in which at least one filter element (3) can be accommodated. The filter element defines a longitudinal axis (25), and has at least two valve units in the form of a bypass valve (V2) and of a pre-pressurizing valve (V1). The valve units are arranged concentric to and along the longitudinal axis (25) of each filter element (3).
    Type: Grant
    Filed: November 4, 2008
    Date of Patent: July 9, 2013
    Assignee: Hydac Filtertechnik GmbH
    Inventors: Werner Wilkendorf, Stefan Marschall
  • Filter Device, Particularly Reflux Vacuum Filter, and Filter Element For Such A Filter Device
    Publication number: 20100257824
    Abstract: The invention relates to a filter device, in particular a reflux vacuum filter, having at least one filter housing (7) in which at least one filter element (3) can be accommodated, the filter element defining a longitudinal axis (25), and having at least two valve units, particularly in the form of a bypass valve (V2) and of a pre-pressurizing valve (V1). The invention is characterized in that the valve units are arranged concentric to the longitudinal axis (25) of each filter element (3) along said longitudinal axis (25).
    Type: Application
    Filed: November 4, 2008
    Publication date: October 14, 2010
    Inventors: Werner Wilkendorf, Stefan Marschall